From b85a3e4ae9a9d2966323a9aeebbd3e2fdb3d431d Mon Sep 17 00:00:00 2001 From: Peter M. Groen Date: Sat, 4 Jun 2022 02:36:52 +0200 Subject: [PATCH] Setting up working version --- src/ConnectionConfig.h | 24 +++++++++++++----------- src/IModbusAdapter.h | 4 ++-- src/ModbusAdapter.cpp | 40 ++++++++++++++++++++++++---------------- src/ModbusAdapter.h | 8 ++++---- src/ModbusConnections.cpp | 69 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ src/ModbusConnections.h | 11 +++++++++++ stack/config.h | 165 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ stack/modbus-data.c | 204 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ stack/modbus-private.h | 101 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ stack/modbus-rtu-private.h | 34 ++++++++++++++++++++++++++++++++++ stack/modbus-rtu.c | 987 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stack/modbus-rtu.h | 34 ++++++++++++++++++++++++++++++++++ stack/modbus-tcp-private.h | 39 +++++++++++++++++++++++++++++++++++++++ stack/modbus-tcp.c | 866 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ stack/modbus-tcp.h | 24 ++++++++++++++++++++++++ stack/modbus-version.h | 34 ++++++++++++++++++++++++++++++++++ stack/modbus.c | 1898 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stack/modbus.h | 262 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 18 files changed, 4771 insertions(+), 33 deletions(-) create mode 100644 stack/config.h create mode 100644 stack/modbus-data.c create mode 100644 stack/modbus-private.h create mode 100644 stack/modbus-rtu-private.h create mode 100644 stack/modbus-rtu.c create mode 100644 stack/modbus-rtu.h create mode 100644 stack/modbus-tcp-private.h create mode 100644 stack/modbus-tcp.c create mode 100644 stack/modbus-tcp.h create mode 100644 stack/modbus-version.h create mode 100644 stack/modbus.c create mode 100644 stack/modbus.h diff --git a/src/ConnectionConfig.h b/src/ConnectionConfig.h index 87d1413..c261fc3 100644 --- a/src/ConnectionConfig.h +++ b/src/ConnectionConfig.h @@ -77,18 +77,18 @@ public: {} // Getters and Setters. Implemented to avoid outside meddling on the member variables. - std::string getPort() const { return m_portMap.at(m_port); } ///< - ConnectionPort getPortEnum() const { return m_port; } ///< - int getBaudRate() const { return m_baudRate; } ///< - char getParity() const { return m_parityMap.at(m_parity); } ///< - int getDataBits() const { return m_dataBits; } ///< - int getStopBits() const { return m_stopBits; } ///< + std::string getPort() const { return m_portMap.at(m_port); } ///< Get the translated portName. + ConnectionPort getPortEnum() const { return m_port; } ///< Get the portname Enum + int getBaudRate() const { return m_baudRate; } ///< Get the given baudrate as int. + char getParity() const { return m_parityMap.at(m_parity); } ///< Get the translated parity. + int getDataBits() const { return m_dataBits; } ///< Get the number of databits ( 7 for ASCII, 8 for RTU ) + int getStopBits() const { return m_stopBits; } ///< Get the number of stopBits. ( de-facto = 1 ) - std::string getIpAddress() const { return m_ipaddress; } ///< - int getTcpPort() const { return m_portnumber; } ///< + std::string getIpAddress() const { return m_ipaddress; } ///< Get the ip-address as string + int getTcpPort() const { return m_portnumber; } ///< Get the tcp portnumber as int - int getTimeOut() const { return m_timeOut; } ///< - ConnectionType getType() const { return m_conType; } ///< + int getTimeOut() const { return m_timeOut; } ///< Get the timeout as a multitude of 0.1 sec. + ConnectionType getType() const { return m_conType; } ///< Get the connection type ( Serial, TCP or Unknown ) private: @@ -107,7 +107,9 @@ private: int m_timeOut; ConnectionType m_conType; - // Change accordingly to the devicenames on your platform. + // ============================================================ + // == Change accordingly to the devicenames on your platform == + // ============================================================ std::unordered_map m_portMap = { { ConnectionPort::CP_EXTERNAL, "/dev/ttyUSB0" }, diff --git a/src/IModbusAdapter.h b/src/IModbusAdapter.h index 18d7e11..e546bf2 100644 --- a/src/IModbusAdapter.h +++ b/src/IModbusAdapter.h @@ -23,12 +23,12 @@ class IModbusAdapter public: virtual ~IModbusAdapter() {} - virtual void ModbusConnect( const ConnectionConfig &conncfg ) = 0; + virtual bool ModbusConnect( const ConnectionConfig &conncfg ) = 0; /*! * \brief ModbusDisconnect */ - virtual void ModbusDisconnect() = 0; + virtual bool ModbusDisconnect() = 0; /*! * \brief ModbusReadData diff --git a/src/ModbusAdapter.cpp b/src/ModbusAdapter.cpp index a492586..fa9f194 100644 --- a/src/ModbusAdapter.cpp +++ b/src/ModbusAdapter.cpp @@ -15,31 +15,33 @@ ModbusAdapter::~ModbusAdapter() } -void ModbusAdapter::ModbusConnect( const ConnectionConfig &conncfg ) +bool ModbusAdapter::ModbusConnect( const ConnectionConfig &conncfg ) { if( m_connected ) { - this->ModbusDisconnect(); + this->ModbusDisconnect(); // Will already set m_connected } - this->m_connType = conncfg.getType(); + m_connType = conncfg.getType(); switch( m_connType ) { case ConnectionType::CT_SERIAL: - this->ModbusConnectRTU( conncfg.getPort(), conncfg.getBaudRate(), conncfg.getParity(), conncfg.getDataBits(), conncfg.getStopBits(), conncfg.getTimeOut(), MODBUS_RTU_RTS_NONE ); + m_connected = this->ModbusConnectRTU( conncfg.getPort(), conncfg.getBaudRate(), conncfg.getParity(), conncfg.getDataBits(), conncfg.getStopBits(), conncfg.getTimeOut(), MODBUS_RTU_RTS_NONE ); break; case ConnectionType::CT_TCP: + m_connected = this->ModbusConnectTCP( conncfg.getIpAddress(), conncfg.getTcpPort(), 10 ); break; default: // throw a sensible message or return an errorcode. break; } + return m_connected; } -void ModbusAdapter::ModbusDisconnect() +bool ModbusAdapter::ModbusDisconnect() { if( m_modbus != nullptr ) { @@ -51,7 +53,9 @@ void ModbusAdapter::ModbusDisconnect() // Clean up after ourselves. m_modbus = nullptr; } + m_connected = false; + return true; } modbusData ModbusAdapter::ModbusReadData( int slaveId, int functionCode, int startAddress, int noOfItems ) @@ -62,8 +66,6 @@ modbusData ModbusAdapter::ModbusReadData( int slaveId, int functionCode, int sta return modbusData(); } - - int resultValue = -1; bool is16Bit = false; @@ -147,6 +149,7 @@ void ModbusAdapter::ModBusWriteData( int slaveId, int functionCode, int startAdd { if( m_modbus == nullptr ) { + // No modbus context. Sensible log-line and exit. return; } @@ -230,7 +233,7 @@ std::string ModbusAdapter::ErrorString( int errnum ) const } /* ============= PRIVATE METHODS ============= */ -void ModbusAdapter::ModbusConnectRTU( const std::string &serialport, int baud, char parity, int dataBits, int stopBits, int RTS, int timeOut ) +bool ModbusAdapter::ModbusConnectRTU( const std::string &serialport, int baud, char parity, int dataBits, int stopBits, int RTS, int timeOut ) { m_modbus = modbus_new_rtu( serialport.c_str(), baud, parity, dataBits, stopBits, RTS ); @@ -242,7 +245,8 @@ void ModbusAdapter::ModbusConnectRTU( const std::string &serialport, int baud, c { // We can stop here. Nothing to be done as we don't have a valid context // Log to PRIVA_LOG - return; + m_connected = false; + return m_connected; } else if( m_modbus && modbus_connect( m_modbus ) == -1 ) { @@ -250,24 +254,26 @@ void ModbusAdapter::ModbusConnectRTU( const std::string &serialport, int baud, c // We can stop here. Nothing to be done as we don't have a valid connection modbus_free( m_modbus ); m_connected = false; - return; + return m_connected; } + m_connected = true; + // Set recovery mode modbus_set_error_recovery( m_modbus, MODBUS_ERROR_RECOVERY_PROTOCOL ); // Set the response timeout modbus_set_response_timeout( m_modbus, timeOut, 0 ); - m_connected = true; + return m_connected; } -void ModbusAdapter::ModbusConnectTCP( const std::string &ip, int port, int timeOut ) +bool ModbusAdapter::ModbusConnectTCP( const std::string &ip, int port, int timeOut ) { if( ip.empty() ) { // Nothing to be done. Set an Logline to PRIVA_LOG and exit. - return; + return false; } m_modbus = modbus_new_tcp( ip.c_str(), port ); @@ -281,7 +287,7 @@ void ModbusAdapter::ModbusConnectTCP( const std::string &ip, int port, int timeO { // We can stop here. Nothing to be done as we don't have a valid context // Log to PRIVA_LOG - return; + return false; } else if( m_modbus && modbus_connect( m_modbus ) == -1 ) { @@ -289,16 +295,18 @@ void ModbusAdapter::ModbusConnectTCP( const std::string &ip, int port, int timeO // We can stop here. Nothing to be done as we don't have a valid connection modbus_free( m_modbus ); m_connected = false; - return; + return m_connected; } + m_connected = true; + // Set recovery mode modbus_set_error_recovery( m_modbus, MODBUS_ERROR_RECOVERY_PROTOCOL ); // Set the response timeout modbus_set_response_timeout( m_modbus, timeOut, 0 ); - m_connected = true; + return m_connected; } void ModbusAdapter::InitBuffers() diff --git a/src/ModbusAdapter.h b/src/ModbusAdapter.h index 9f3d4af..9128e8f 100644 --- a/src/ModbusAdapter.h +++ b/src/ModbusAdapter.h @@ -34,12 +34,12 @@ public: * \brief ModbusConnect * \param conncfg */ - void ModbusConnect( const ConnectionConfig &conncfg ) override; + bool ModbusConnect( const ConnectionConfig &conncfg ) override; /*! * \brief ModbusDisconnect */ - void ModbusDisconnect() override; + bool ModbusDisconnect() override; /*! * \brief ModbusReadData @@ -82,8 +82,8 @@ public: std::string ErrorString( int errnum ) const override; private: // Methods - void ModbusConnectRTU( const std::string &serialport, int baud, char parity, int dataBits, int stopBits, int RTS, int timeOut ); - void ModbusConnectTCP( const std::string &ip, int port, int timeOut = -1 ); + bool ModbusConnectRTU( const std::string &serialport, int baud, char parity, int dataBits, int stopBits, int RTS, int timeOut ); + bool ModbusConnectTCP( const std::string &ip, int port, int timeOut = -1 ); void InitBuffers(); void ClearBuffers(); diff --git a/src/ModbusConnections.cpp b/src/ModbusConnections.cpp index 3e438a6..89cce7c 100644 --- a/src/ModbusConnections.cpp +++ b/src/ModbusConnections.cpp @@ -50,11 +50,17 @@ bool ModbusConnections::CreateConnection( const ConnectionConfig &config ) if( config.getType() == ConnectionType::CT_TCP ) { + // === Critical Section === + std::lock_guard guard( m_mapTcpMutex ); m_mapTcp.insert( { createEndPoint( config ), ptrNewAdapter } ); + // === End Critical Section === } else if( config.getType() == ConnectionType::CT_SERIAL ) { + // === Critical Section === + std::lock_guard guard( m_mapSerialMutex ); m_mapSerial.insert( { config.getPortEnum(), ptrNewAdapter } ); + // === End Critical Section === } else { @@ -67,7 +73,36 @@ bool ModbusConnections::CreateConnection( const ConnectionConfig &config ) bool ModbusConnections::DeleteConnection( const ConnectionPort portName, const std::string &endpoint ) { + std::shared_ptr ptr = this->connectionExist( portName, endpoint ); + if( ptr == nullptr ) + { + // Seems like it is already gone. Shouldn't happen, but ok. + return false; + } + // First remove it from the map. + if( portName == ConnectionPort::CP_TCP ) + { + // === Critical Section === + std::lock_guard guard( m_mapTcpMutex ); + m_mapTcp.erase( endpoint ); + // === End Critical Section === + } + else + { + // === Critical Section === + std::lock_guard guard( m_mapSerialMutex ); + m_mapSerial.erase( portName ); + // === End Critical Section === + } + + // Call the disconnect for a clean exit. + ptr->ModbusDisconnect(); + + // Delete the pointer or decrease the ref-count + ptr.reset(); + + return true; } int ModbusConnections::ConnectionCount() @@ -80,6 +115,40 @@ std::shared_ptr ModbusConnections::getConnection( const Connecti return this->connectionExist( portName, endpoint ); } +std::shared_ptr ModbusConnections::getConnection( const ConnectionPort portName, const std::string &ipAddress, int tcpPortNumber ) +{ + return this->connectionExist( portName, this->createEndPoint( ipAddress, tcpPortNumber ) ); +} + +AdapterList ModbusConnections::getConnections() +{ + AdapterList lstResult; + + { + // === Critical Section === + std::lock_guard guard(m_mapSerialMutex); + // First we pick up the Serial Map + for( auto const& [key, value] : m_mapSerial ) + { + lstResult.push_back( value ); + } + // === End Critical Section === + } + + { + // === Critical Section === + std::lock_guard guard(m_mapTcpMutex); + // Next we pick all the entries in the tcp-map + for( auto const& [key, value] : m_mapTcp ) + { + lstResult.push_back( value ); + } + // === End Critical Section === + } + + return lstResult; +} + std::shared_ptr ModbusConnections::connectionExist( const ConnectionPort portName, const std::string &endpoint ) { if( portName == ConnectionPort::CP_TCP ) diff --git a/src/ModbusConnections.h b/src/ModbusConnections.h index 7a402f8..b345285 100644 --- a/src/ModbusConnections.h +++ b/src/ModbusConnections.h @@ -9,9 +9,12 @@ // std #include +#include #include #include +using AdapterList = std::vector>; + class ModbusConnections { public: @@ -64,6 +67,12 @@ public: */ std::shared_ptr getConnection( const ConnectionPort portName, const std::string &ipAddress, int tcpPortNumber ); + /*! + * \brief getConnections + * \return + */ + AdapterList getConnections(); + private: /*! * \brief connectionExist @@ -89,6 +98,8 @@ private: std::string createEndPoint( const ConnectionConfig &config ); private: + std::mutex m_mapSerialMutex; ///< Mutex protecting the serialmap + std::mutex m_mapTcpMutex; ///< Mutex protecting the TCPmap std::unordered_map> m_mapSerial; ///< Unordered map holding the Modbus connections By PortName std::unordered_map> m_mapTcp; ///< Unordered map holding the Modbus connections By tcp://endpoint:port }; diff --git a/stack/config.h b/stack/config.h new file mode 100644 index 0000000..66546e4 --- /dev/null +++ b/stack/config.h @@ -0,0 +1,165 @@ +/* Define to 1 if you have the header file. */ +#define HAVE_ARPA_INET_H 1 + +/* Define to 1 if you have the declaration of `TIOCSRS485', and to 0 if you don't. */ +#define HAVE_DECL_TIOCSRS485 0 + +/* Define to 1 if you have the declaration of `TIOCM_RTS', and to 0 if you don't. */ +#define HAVE_DECL_TIOCM_RTS 0 + +/* Define to 1 if you have the declaration of `__CYGWIN__', and to 0 if you don't. */ +#define HAVE_DECL___CYGWIN__ 0 + +/* Define to 1 if you have the header file. */ +#define HAVE_DLFCN_H 1 + +/* Define to 1 if you have the header file. */ +#define HAVE_ERRNO_H 1 + +/* Define to 1 if you have the header file. */ +#define HAVE_FCNTL_H 1 + +/* Define to 1 if you have the `fork' function. */ +#define HAVE_FORK 1 + +/* Define to 1 if you have the `getaddrinfo' function. */ +#define HAVE_GETADDRINFO 1 + +/* Define to 1 if you have the `gettimeofday' function. */ +#define HAVE_GETTIMEOFDAY 1 + +/* Define to 1 if you have the `inet_ntoa' function. */ +#define HAVE_INET_NTOA 1 + +/* Define to 1 if you have the header file. */ +#define HAVE_INTTYPES_H 1 + +/* Define to 1 if you have the header file. */ +#define HAVE_LIMITS_H 1 + +/* Define to 1 if you have the header file. */ +#define HAVE_LINUX_SERIAL_H 1 + +/* Define to 1 if you have the header file. */ +#define HAVE_MEMORY_H 1 + +/* Define to 1 if you have the `memset' function. */ +#define HAVE_MEMSET 1 + +/* Define to 1 if you have the header file. */ +#define HAVE_NETDB_H 1 + +/* Define to 1 if you have the header file. */ +#define HAVE_NETINET_IN_H 1 + +/* Define to 1 if you have the header file. */ +#define HAVE_NETINET_TCP_H 1 + +/* Define to 1 if you have the `select' function. */ +#define HAVE_SELECT 1 + +/* Define to 1 if you have the `socket' function. */ +#define HAVE_SOCKET 1 + +/* Define to 1 if you have the header file. */ +#define HAVE_STDINT_H 1 + +/* Define to 1 if you have the header file. */ +#define HAVE_STDLIB_H 1 + +/* Define to 1 if you have the `strerror' function. */ +#define HAVE_STRERROR 1 + +/* Define to 1 if you have the header file. */ +#define HAVE_STRINGS_H 1 + +/* Define to 1 if you have the header file. */ +#define HAVE_STRING_H 1 + +/* Define to 1 if you have the `strlcpy' function. */ +/* #undef HAVE_STRLCPY */ + +/* Define to 1 if you have the header file. */ +#define HAVE_SYS_IOCTL_H 1 + +/* Define to 1 if you have the header file. */ +#define HAVE_SYS_SOCKET_H 1 + +/* Define to 1 if you have the header file. */ +#define HAVE_SYS_STAT_H 1 + +/* Define to 1 if you have the header file. */ +#define HAVE_SYS_TIME_H 1 + +/* Define to 1 if you have the header file. */ +#define HAVE_SYS_TYPES_H 1 + +/* Define to 1 if you have the header file. */ +#define HAVE_TERMIOS_H 1 + +/* Define to 1 if you have the header file. */ +#define HAVE_TIME_H 1 + +/* Define to 1 if you have the header file. */ +#define HAVE_UNISTD_H 1 + +/* Define to 1 if you have the `vfork' function. */ +#define HAVE_VFORK 1 + +/* Define to 1 if you have the header file. */ +/* #undef HAVE_VFORK_H */ + +/* Define to 1 if you have the header file. */ +/* #undef HAVE_WINSOCK2_H */ + +/* Define to 1 if `fork' works. */ +#define HAVE_WORKING_FORK 1 + +/* Define to 1 if `vfork' works. */ +#define HAVE_WORKING_VFORK 1 + +/* Define to the sub-directory in which libtool stores uninstalled libraries. + */ +#define LT_OBJDIR ".libs/" + +/* Name of package */ +#define PACKAGE "libmodbus" + +/* Define to the address where bug reports for this package should be sent. */ +#define PACKAGE_BUGREPORT "https://github.com/stephane/libmodbus/issues" + +/* Define to the full name of this package. */ +#define PACKAGE_NAME "libmodbus" + +/* Define to the full name and version of this package. */ +#define PACKAGE_STRING "libmodbus 3.1.0-1" + +/* Define to the one symbol short name of this package. */ +#define PACKAGE_TARNAME "modbus" + +/* Define to the home page for this package. */ +#define PACKAGE_URL "" + +/* Define to the version of this package. */ +#define PACKAGE_VERSION "1.0.0" + +/* Define to 1 if you have the ANSI C header files. */ +#define STDC_HEADERS 1 + +/* Define to 1 if you can safely include both and . */ +#define TIME_WITH_SYS_TIME 1 + +/* Version number of package */ +#define VERSION "1.0.0" + +/* Define to empty if `const' does not conform to ANSI C. */ +/* #undef const */ + +/* Define to `int' if does not define. */ +/* #undef pid_t */ + +/* Define to `unsigned int' if does not define. */ +/* #undef size_t */ + +/* Define as `fork' if `vfork' does not work. */ +/* #undef vfork */ diff --git a/stack/modbus-data.c b/stack/modbus-data.c new file mode 100644 index 0000000..a789cf7 --- /dev/null +++ b/stack/modbus-data.c @@ -0,0 +1,204 @@ + +#include + +#include "stdint.h" + +#include +#include +#include +#include + +#include "modbus.h" + +#if defined(HAVE_BYTESWAP_H) +# include +#endif + +#if defined(__GNUC__) +# define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__ * 10) +# if GCC_VERSION >= 430 +// Since GCC >= 4.30, GCC provides __builtin_bswapXX() alternatives so we switch to them +# undef bswap_32 +# define bswap_32 __builtin_bswap32 +# endif +#endif + +#if !defined(__CYGWIN__) && !defined(bswap_16) +#pragma message "Fallback on C functions for bswap_16" +static inline uint16_t bswap_16(uint16_t x) +{ + return (x >> 8) | (x << 8); +} +#endif + +#if !defined(bswap_32) +#pragma message "Fallback on C functions for bswap_32" +static inline uint32_t bswap_32(uint32_t x) +{ + return (bswap_16(x & 0xffff) << 16) | (bswap_16(x >> 16)); +} +#endif + +/* Sets many bits from a single byte value (all 8 bits of the byte value are + set) */ +void modbus_set_bits_from_byte( uint8_t *dest, int idx, const uint8_t value ) +{ + int i; + + for (i=0; i < 8; i++) + { + dest[idx+i] = (value & (1 << i)) ? 1 : 0; + } +} + +/* Sets many bits from a table of bytes (only the bits between idx and + idx + nb_bits are set) */ +void modbus_set_bits_from_bytes( uint8_t *dest, int idx, unsigned int nb_bits, const uint8_t *tab_byte ) +{ + unsigned int i; + int shift = 0; + + for ( i = idx; i < idx + nb_bits; i++ ) + { + dest[i] = tab_byte[(i - idx) / 8] & (1 << shift) ? 1 : 0; + /* gcc doesn't like: shift = (++shift) % 8; */ + shift++; + shift %= 8; + } +} + +/* Gets the byte value from many bits. + To obtain a full byte, set nb_bits to 8. */ +uint8_t modbus_get_byte_from_bits( const uint8_t *src, int idx, unsigned int nb_bits ) +{ + unsigned int i; + uint8_t value = 0; + + if (nb_bits > 8) + { + /* Assert is ignored if NDEBUG is set */ + assert(nb_bits < 8); + nb_bits = 8; + } + + for (i=0; i < nb_bits; i++) + { + value |= (src[idx+i] << i); + } + + return value; +} + +/* Get a float from 4 bytes (Modbus) without any conversion (ABCD) */ +float modbus_get_float_abcd(const uint16_t *src) +{ + float f; + uint32_t i; + + i = ntohl(((uint32_t)src[0] << 16) + src[1]); + memcpy(&f, &i, sizeof(float)); + + return f; +} + +/* Get a float from 4 bytes (Modbus) in inversed format (DCBA) */ +float modbus_get_float_dcba(const uint16_t *src) +{ + float f; + uint32_t i; + + i = ntohl(bswap_32((((uint32_t)src[0]) << 16) + src[1])); + memcpy(&f, &i, sizeof(float)); + + return f; +} + +/* Get a float from 4 bytes (Modbus) with swapped bytes (BADC) */ +float modbus_get_float_badc(const uint16_t *src) +{ + float f; + uint32_t i; + + i = ntohl((uint32_t)(bswap_16(src[0]) << 16) + bswap_16(src[1])); + memcpy(&f, &i, sizeof(float)); + + return f; +} + +/* Get a float from 4 bytes (Modbus) with swapped words (CDAB) */ +float modbus_get_float_cdab(const uint16_t *src) +{ + float f; + uint32_t i; + + i = ntohl((((uint32_t)src[1]) << 16) + src[0]); + memcpy(&f, &i, sizeof(float)); + + return f; +} + +/* DEPRECATED - Get a float from 4 bytes in sort of Modbus format */ +float modbus_get_float(const uint16_t *src) +{ + float f; + uint32_t i; + + i = (((uint32_t)src[1]) << 16) + src[0]; + memcpy(&f, &i, sizeof(float)); + + return f; +} + +/* Set a float to 4 bytes for Modbus w/o any conversion (ABCD) */ +void modbus_set_float_abcd(float f, uint16_t *dest) +{ + uint32_t i; + + memcpy(&i, &f, sizeof(uint32_t)); + i = htonl(i); + dest[0] = (uint16_t)(i >> 16); + dest[1] = (uint16_t)i; +} + +/* Set a float to 4 bytes for Modbus with byte and word swap conversion (DCBA) */ +void modbus_set_float_dcba(float f, uint16_t *dest) +{ + uint32_t i; + + memcpy(&i, &f, sizeof(uint32_t)); + i = bswap_32(htonl(i)); + dest[0] = (uint16_t)(i >> 16); + dest[1] = (uint16_t)i; +} + +/* Set a float to 4 bytes for Modbus with byte swap conversion (BADC) */ +void modbus_set_float_badc(float f, uint16_t *dest) +{ + uint32_t i; + + memcpy(&i, &f, sizeof(uint32_t)); + i = htonl(i); + dest[0] = (uint16_t)bswap_16(i >> 16); + dest[1] = (uint16_t)bswap_16(i & 0xFFFF); +} + +/* Set a float to 4 bytes for Modbus with word swap conversion (CDAB) */ +void modbus_set_float_cdab(float f, uint16_t *dest) +{ + uint32_t i; + + memcpy(&i, &f, sizeof(uint32_t)); + i = htonl(i); + dest[0] = (uint16_t)i; + dest[1] = (uint16_t)(i >> 16); +} + +/* DEPRECATED - Set a float to 4 bytes in a sort of Modbus format! */ +void modbus_set_float(float f, uint16_t *dest) +{ + uint32_t i; + + memcpy(&i, &f, sizeof(uint32_t)); + dest[0] = (uint16_t)i; + dest[1] = (uint16_t)(i >> 16); +} diff --git a/stack/modbus-private.h b/stack/modbus-private.h new file mode 100644 index 0000000..248a154 --- /dev/null +++ b/stack/modbus-private.h @@ -0,0 +1,101 @@ + +#pragma once + +# include +# include +#include +#include + +#include "modbus.h" + +MODBUS_BEGIN_DECLS + +/* It's not really the minimal length (the real one is report slave ID + * in RTU (4 bytes)) but it's a convenient size to use in RTU or TCP + * communications to read many values or write a single one. + * Maximum between : + * - HEADER_LENGTH_TCP (7) + function (1) + address (2) + number (2) + * - HEADER_LENGTH_RTU (1) + function (1) + address (2) + number (2) + CRC (2) + */ +#define _MIN_REQ_LENGTH 12 +#define _REPORT_SLAVE_ID 180 +#define _MODBUS_EXCEPTION_RSP_LENGTH 5 + +/* Timeouts in microsecond (0.5 s) */ +#define _RESPONSE_TIMEOUT 500000 +#define _BYTE_TIMEOUT 500000 + +typedef enum +{ + _MODBUS_BACKEND_TYPE_RTU=0, + _MODBUS_BACKEND_TYPE_TCP +} modbus_backend_type_t; + +/* + * ---------- Request Indication ---------- + * | Client | ---------------------->| Server | + * ---------- Confirmation Response ---------- + */ +typedef enum +{ + /* Request message on the server side */ + MSG_INDICATION, + /* Request message on the client side */ + MSG_CONFIRMATION +} msg_type_t; + +/* This structure reduces the number of params in functions and so + * optimizes the speed of execution (~ 37%). */ +typedef struct _sft +{ + int slave; + int function; + int t_id; +} sft_t; + +typedef struct _modbus_backend +{ + unsigned int backend_type; + unsigned int header_length; + unsigned int checksum_length; + unsigned int max_adu_length; + int (*set_slave) (modbus_t *ctx, int slave); + int (*build_request_basis) (modbus_t *ctx, int function, int addr, int nb, uint8_t *req); + int (*build_response_basis) (sft_t *sft, uint8_t *rsp); + int (*prepare_response_tid) (const uint8_t *req, int *req_length); + int (*send_msg_pre) (uint8_t *req, int req_length); + ssize_t (*send) (modbus_t *ctx, const uint8_t *req, int req_length); + int (*receive) (modbus_t *ctx, uint8_t *req); + ssize_t (*recv) (modbus_t *ctx, uint8_t *rsp, int rsp_length); + int (*check_integrity) (modbus_t *ctx, uint8_t *msg, const int msg_length); + int (*pre_check_confirmation) (modbus_t *ctx, const uint8_t *req, const uint8_t *rsp, int rsp_length); + int (*connect) (modbus_t *ctx); + void (*close) (modbus_t *ctx); + int (*flush) (modbus_t *ctx); + int (*select) (modbus_t *ctx, fd_set *rset, struct timeval *tv, int msg_length); + void (*free) (modbus_t *ctx); +} modbus_backend_t; + +struct _modbus +{ + /* Slave address */ + int slave; + /* Socket or file descriptor */ + int s; + int debug; + int error_recovery; + struct timeval response_timeout; + struct timeval byte_timeout; + const modbus_backend_t *backend; + void *backend_data; +}; + +void _modbus_init_common(modbus_t *ctx); +void _error_print(modbus_t *ctx, const char *context); +int _modbus_receive_msg(modbus_t *ctx, uint8_t *msg, msg_type_t msg_type); + +#ifndef HAVE_STRLCPY +size_t strlcpy(char *dest, const char *src, size_t dest_size); +#endif + +MODBUS_END_DECLS diff --git a/stack/modbus-rtu-private.h b/stack/modbus-rtu-private.h new file mode 100644 index 0000000..3dd901a --- /dev/null +++ b/stack/modbus-rtu-private.h @@ -0,0 +1,34 @@ + +#pragma once + +#include +#include + +#define _MODBUS_RTU_HEADER_LENGTH 1 +#define _MODBUS_RTU_PRESET_REQ_LENGTH 6 +#define _MODBUS_RTU_PRESET_RSP_LENGTH 2 + +#define _MODBUS_RTU_CHECKSUM_LENGTH 2 + +typedef struct _modbus_rtu +{ + /* Device: "/dev/ttyS0", "/dev/ttyUSB0" or "/dev/tty.USA19*" on Mac OS X. */ + char *device; + /* Bauds: 9600, 19200, 57600, 115200, etc */ + int baud; + /* Data bit */ + uint8_t data_bit; + /* Stop bit */ + uint8_t stop_bit; + /* Parity: 'N', 'O', 'E' */ + char parity; + /* Save old termios settings */ + struct termios old_tios; + +#if HAVE_DECL_TIOCSRS485 + int serial_mode; +#endif + + /* To handle many slaves on the same link */ + int confirmation_to_ignore; +} modbus_rtu_t; diff --git a/stack/modbus-rtu.c b/stack/modbus-rtu.c new file mode 100644 index 0000000..770762f --- /dev/null +++ b/stack/modbus-rtu.c @@ -0,0 +1,987 @@ + +#include +#include +#include +#include +#include +#include +#include + +#include "modbus-private.h" + +#include "modbus-rtu.h" +#include "modbus-rtu-private.h" + +#if HAVE_DECL_TIOCSRS485 || HAVE_DECL_TIOCM_RTS +#include +#endif + +#if HAVE_DECL_TIOCSRS485 +#include +#endif + +/* Table of CRC values for high-order byte */ +static const uint8_t table_crc_hi[] = { + 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, + 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, + 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, + 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, + 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, + 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, + 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, + 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, + 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, + 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, + 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, + 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, + 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, + 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, + 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, + 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, + 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, + 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, + 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, + 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, + 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, + 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, + 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, + 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, + 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, + 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40 +}; + +/* Table of CRC values for low-order byte */ +static const uint8_t table_crc_lo[] = { + 0x00, 0xC0, 0xC1, 0x01, 0xC3, 0x03, 0x02, 0xC2, 0xC6, 0x06, + 0x07, 0xC7, 0x05, 0xC5, 0xC4, 0x04, 0xCC, 0x0C, 0x0D, 0xCD, + 0x0F, 0xCF, 0xCE, 0x0E, 0x0A, 0xCA, 0xCB, 0x0B, 0xC9, 0x09, + 0x08, 0xC8, 0xD8, 0x18, 0x19, 0xD9, 0x1B, 0xDB, 0xDA, 0x1A, + 0x1E, 0xDE, 0xDF, 0x1F, 0xDD, 0x1D, 0x1C, 0xDC, 0x14, 0xD4, + 0xD5, 0x15, 0xD7, 0x17, 0x16, 0xD6, 0xD2, 0x12, 0x13, 0xD3, + 0x11, 0xD1, 0xD0, 0x10, 0xF0, 0x30, 0x31, 0xF1, 0x33, 0xF3, + 0xF2, 0x32, 0x36, 0xF6, 0xF7, 0x37, 0xF5, 0x35, 0x34, 0xF4, + 0x3C, 0xFC, 0xFD, 0x3D, 0xFF, 0x3F, 0x3E, 0xFE, 0xFA, 0x3A, + 0x3B, 0xFB, 0x39, 0xF9, 0xF8, 0x38, 0x28, 0xE8, 0xE9, 0x29, + 0xEB, 0x2B, 0x2A, 0xEA, 0xEE, 0x2E, 0x2F, 0xEF, 0x2D, 0xED, + 0xEC, 0x2C, 0xE4, 0x24, 0x25, 0xE5, 0x27, 0xE7, 0xE6, 0x26, + 0x22, 0xE2, 0xE3, 0x23, 0xE1, 0x21, 0x20, 0xE0, 0xA0, 0x60, + 0x61, 0xA1, 0x63, 0xA3, 0xA2, 0x62, 0x66, 0xA6, 0xA7, 0x67, + 0xA5, 0x65, 0x64, 0xA4, 0x6C, 0xAC, 0xAD, 0x6D, 0xAF, 0x6F, + 0x6E, 0xAE, 0xAA, 0x6A, 0x6B, 0xAB, 0x69, 0xA9, 0xA8, 0x68, + 0x78, 0xB8, 0xB9, 0x79, 0xBB, 0x7B, 0x7A, 0xBA, 0xBE, 0x7E, + 0x7F, 0xBF, 0x7D, 0xBD, 0xBC, 0x7C, 0xB4, 0x74, 0x75, 0xB5, + 0x77, 0xB7, 0xB6, 0x76, 0x72, 0xB2, 0xB3, 0x73, 0xB1, 0x71, + 0x70, 0xB0, 0x50, 0x90, 0x91, 0x51, 0x93, 0x53, 0x52, 0x92, + 0x96, 0x56, 0x57, 0x97, 0x55, 0x95, 0x94, 0x54, 0x9C, 0x5C, + 0x5D, 0x9D, 0x5F, 0x9F, 0x9E, 0x5E, 0x5A, 0x9A, 0x9B, 0x5B, + 0x99, 0x59, 0x58, 0x98, 0x88, 0x48, 0x49, 0x89, 0x4B, 0x8B, + 0x8A, 0x4A, 0x4E, 0x8E, 0x8F, 0x4F, 0x8D, 0x4D, 0x4C, 0x8C, + 0x44, 0x84, 0x85, 0x45, 0x87, 0x47, 0x46, 0x86, 0x82, 0x42, + 0x43, 0x83, 0x41, 0x81, 0x80, 0x40 +}; + +/* Define the slave ID of the remote device to talk in master mode or set the + * internal slave ID in slave mode */ +static int _modbus_set_slave( modbus_t *ctx, int slave ) +{ + /* Broadcast address is 0 (MODBUS_BROADCAST_ADDRESS) */ + if (slave >= 0 && slave <= 247) + { + ctx->slave = slave; + } + else + { + errno = EINVAL; + return -1; + } + + return 0; +} + +/* Builds a RTU request header */ +static int _modbus_rtu_build_request_basis( modbus_t *ctx, int function, int addr, int nb, uint8_t *req ) +{ + assert(ctx->slave != -1); + req[0] = ctx->slave; + req[1] = function; + req[2] = addr >> 8; + req[3] = addr & 0x00ff; + req[4] = nb >> 8; + req[5] = nb & 0x00ff; + + return _MODBUS_RTU_PRESET_REQ_LENGTH; +} + +/* Builds a RTU response header */ +static int _modbus_rtu_build_response_basis( sft_t *sft, uint8_t *rsp ) +{ + /* In this case, the slave is certainly valid because a check is already + * done in _modbus_rtu_listen */ + rsp[0] = sft->slave; + rsp[1] = sft->function; + + return _MODBUS_RTU_PRESET_RSP_LENGTH; +} + +static uint16_t crc16( uint8_t *buffer, uint16_t buffer_length ) +{ + uint8_t crc_hi = 0xFF; /* high CRC byte initialized */ + uint8_t crc_lo = 0xFF; /* low CRC byte initialized */ + unsigned int i; /* will index into CRC lookup */ + + /* pass through message buffer */ + while (buffer_length--) { + i = crc_hi ^ *buffer++; /* calculate the CRC */ + crc_hi = crc_lo ^ table_crc_hi[i]; + crc_lo = table_crc_lo[i]; + } + + return (crc_hi << 8 | crc_lo); +} + +static int _modbus_rtu_prepare_response_tid( const uint8_t *req, int *req_length ) +{ + (*req_length) -= _MODBUS_RTU_CHECKSUM_LENGTH; + /* No TID */ + return 0; +} + +static int _modbus_rtu_send_msg_pre( uint8_t *req, int req_length ) +{ + uint16_t crc = crc16( req, req_length ); + req[req_length++] = crc >> 8; + req[req_length++] = crc & 0x00FF; + + return req_length; +} + +#if HAVE_DECL_TIOCM_RTS +static void _modbus_rtu_ioctl_rts( modbus_t *ctx, int on ) +{ + int fd = ctx->s; + int flags; + + ioctl(fd, TIOCMGET, &flags); + if (on) + { + flags |= TIOCM_RTS; + } + else + { + flags &= ~TIOCM_RTS; + } + ioctl(fd, TIOCMSET, &flags); +} +#endif + +static ssize_t _modbus_rtu_send( modbus_t *ctx, const uint8_t *req, int req_length ) +{ +#if HAVE_DECL_TIOCM_RTS + modbus_rtu_t *ctx_rtu = ctx->backend_data; + if (ctx_rtu->rts != MODBUS_RTU_RTS_NONE) + { + ssize_t size; + + if (ctx->debug) { + fprintf(stderr, "Sending request using RTS signal\n"); + } + + ctx_rtu->set_rts(ctx, ctx_rtu->rts == MODBUS_RTU_RTS_UP); + usleep(ctx_rtu->rts_delay); + + size = write(ctx->s, req, req_length); + + usleep(ctx_rtu->onebyte_time * req_length + ctx_rtu->rts_delay); + ctx_rtu->set_rts(ctx, ctx_rtu->rts != MODBUS_RTU_RTS_UP); + + return size; + } + else + { +#endif + return write(ctx->s, req, req_length); +#if HAVE_DECL_TIOCM_RTS + } +#endif +} + +static int _modbus_rtu_receive( modbus_t *ctx, uint8_t *req ) +{ + int rc; + modbus_rtu_t *ctx_rtu = ctx->backend_data; + + if( ctx_rtu->confirmation_to_ignore ) + { + _modbus_receive_msg(ctx, req, MSG_CONFIRMATION); + /* Ignore errors and reset the flag */ + ctx_rtu->confirmation_to_ignore = FALSE; + rc = 0; + if( ctx->debug ) + { + printf("Confirmation to ignore\n"); + } + } + else + { + rc = _modbus_receive_msg( ctx, req, MSG_INDICATION ); + if( rc == 0 ) + { + /* The next expected message is a confirmation to ignore */ + ctx_rtu->confirmation_to_ignore = TRUE; + } + } + return rc; +} + +static ssize_t _modbus_rtu_recv( modbus_t *ctx, uint8_t *rsp, int rsp_length ) +{ + return read(ctx->s, rsp, rsp_length); +} + +static int _modbus_rtu_flush(modbus_t *); + +static int _modbus_rtu_pre_check_confirmation(modbus_t *ctx, const uint8_t *req, const uint8_t *rsp, int rsp_length) +{ + /* Check responding slave is the slave we requested (except for broacast request) */ + if (req[0] != rsp[0] && req[0] != MODBUS_BROADCAST_ADDRESS) + { + if (ctx->debug) + { + fprintf(stderr, "The responding slave %d isn't the requested slave %d\n", rsp[0], req[0]); + } + errno = EMBBADSLAVE; + return -1; + } + + return 0; +} + +/* The check_crc16 function shall return 0 is the message is ignored and the + message length if the CRC is valid. Otherwise it shall return -1 and set + errno to EMBADCRC. */ +static int _modbus_rtu_check_integrity(modbus_t *ctx, uint8_t *msg, const int msg_length) +{ + uint16_t crc_calculated; + uint16_t crc_received; + int slave = msg[0]; + + /* Filter on the Modbus unit identifier (slave) in RTU mode to avoid useless + * CRC computing. */ + if (slave != ctx->slave && slave != MODBUS_BROADCAST_ADDRESS) + { + if (ctx->debug) + { + printf("Request for slave %d ignored (not %d)\n", slave, ctx->slave); + } + /* Following call to check_confirmation handles this error */ + return 0; + } + + crc_calculated = crc16(msg, msg_length - 2); + crc_received = (msg[msg_length - 2] << 8) | msg[msg_length - 1]; + + /* Check CRC of msg */ + if (crc_calculated == crc_received) + { + return msg_length; + } + else + { + if (ctx->debug) + { + fprintf(stderr, "ERROR CRC received 0x%0X != CRC calculated 0x%0X\n", + crc_received, crc_calculated); + } + + if (ctx->error_recovery & MODBUS_ERROR_RECOVERY_PROTOCOL) + { + _modbus_rtu_flush(ctx); + } + errno = EMBBADCRC; + return -1; + } +} + +/* Sets up a serial port for RTU communications */ +static int _modbus_rtu_connect(modbus_t *ctx) +{ + struct termios tios; + speed_t speed; + int flags; + + modbus_rtu_t *ctx_rtu = ctx->backend_data; + + if (ctx->debug) + { + printf("Opening %s at %d bauds (%c, %d, %d)\n", + ctx_rtu->device, ctx_rtu->baud, ctx_rtu->parity, ctx_rtu->data_bit, ctx_rtu->stop_bit); + } + + /* The O_NOCTTY flag tells UNIX that this program doesn't want + to be the "controlling terminal" for that port. If you + don't specify this then any input (such as keyboard abort + signals and so forth) will affect your process + + Timeouts are ignored in canonical input mode or when the + NDELAY option is set on the file via open or fcntl */ + flags = O_RDWR | O_NOCTTY | O_NDELAY | O_EXCL; +#ifdef O_CLOEXEC + flags |= O_CLOEXEC; +#endif + + ctx->s = open(ctx_rtu->device, flags); + if (ctx->s == -1) { + if (ctx->debug) { + fprintf(stderr, "ERROR Can't open the device %s (%s)\n", + ctx_rtu->device, strerror(errno)); + } + return -1; + } + + /* Save */ + tcgetattr(ctx->s, &ctx_rtu->old_tios); + + memset(&tios, 0, sizeof(struct termios)); + + /* C_ISPEED Input baud (new interface) + C_OSPEED Output baud (new interface) + */ + switch (ctx_rtu->baud) + { + case 110: + speed = B110; + break; + case 300: + speed = B300; + break; + case 600: + speed = B600; + break; + case 1200: + speed = B1200; + break; + case 2400: + speed = B2400; + break; + case 4800: + speed = B4800; + break; + case 9600: + speed = B9600; + break; + case 19200: + speed = B19200; + break; + case 38400: + speed = B38400; + break; +#ifdef B57600 + case 57600: + speed = B57600; + break; +#endif +#ifdef B115200 + case 115200: + speed = B115200; + break; +#endif +#ifdef B230400 + case 230400: + speed = B230400; + break; +#endif +#ifdef B460800 + case 460800: + speed = B460800; + break; +#endif +#ifdef B500000 + case 500000: + speed = B500000; + break; +#endif +#ifdef B576000 + case 576000: + speed = B576000; + break; +#endif +#ifdef B921600 + case 921600: + speed = B921600; + break; +#endif +#ifdef B1000000 + case 1000000: + speed = B1000000; + break; +#endif +#ifdef B1152000 + case 1152000: + speed = B1152000; + break; +#endif +#ifdef B1500000 + case 1500000: + speed = B1500000; + break; +#endif +#ifdef B2500000 + case 2500000: + speed = B2500000; + break; +#endif +#ifdef B3000000 + case 3000000: + speed = B3000000; + break; +#endif +#ifdef B3500000 + case 3500000: + speed = B3500000; + break; +#endif +#ifdef B4000000 + case 4000000: + speed = B4000000; + break; +#endif + default: + speed = B9600; + if (ctx->debug) { + fprintf(stderr, + "WARNING Unknown baud rate %d for %s (B9600 used)\n", + ctx_rtu->baud, ctx_rtu->device); + } + } + + /* Set the baud rate */ + if ((cfsetispeed(&tios, speed) < 0) || + (cfsetospeed(&tios, speed) < 0)) { + close(ctx->s); + ctx->s = -1; + return -1; + } + + /* C_CFLAG Control options + CLOCAL Local line - do not change "owner" of port + CREAD Enable receiver + */ + tios.c_cflag |= (CREAD | CLOCAL); + /* CSIZE, HUPCL, CRTSCTS (hardware flow control) */ + + /* Set data bits (5, 6, 7, 8 bits) + CSIZE Bit mask for data bits + */ + tios.c_cflag &= ~CSIZE; + switch (ctx_rtu->data_bit) { + case 5: + tios.c_cflag |= CS5; + break; + case 6: + tios.c_cflag |= CS6; + break; + case 7: + tios.c_cflag |= CS7; + break; + case 8: + default: + tios.c_cflag |= CS8; + break; + } + + /* Stop bit (1 or 2) */ + if (ctx_rtu->stop_bit == 1) + tios.c_cflag &=~ CSTOPB; + else /* 2 */ + tios.c_cflag |= CSTOPB; + + /* PARENB Enable parity bit + PARODD Use odd parity instead of even */ + if (ctx_rtu->parity == 'N') { + /* None */ + tios.c_cflag &=~ PARENB; + } else if (ctx_rtu->parity == 'E') { + /* Even */ + tios.c_cflag |= PARENB; + tios.c_cflag &=~ PARODD; + } else { + /* Odd */ + tios.c_cflag |= PARENB; + tios.c_cflag |= PARODD; + } + + /* Read the man page of termios if you need more information. */ + + /* This field isn't used on POSIX systems + tios.c_line = 0; + */ + + /* C_LFLAG Line options + + ISIG Enable SIGINTR, SIGSUSP, SIGDSUSP, and SIGQUIT signals + ICANON Enable canonical input (else raw) + XCASE Map uppercase \lowercase (obsolete) + ECHO Enable echoing of input characters + ECHOE Echo erase character as BS-SP-BS + ECHOK Echo NL after kill character + ECHONL Echo NL + NOFLSH Disable flushing of input buffers after + interrupt or quit characters + IEXTEN Enable extended functions + ECHOCTL Echo control characters as ^char and delete as ~? + ECHOPRT Echo erased character as character erased + ECHOKE BS-SP-BS entire line on line kill + FLUSHO Output being flushed + PENDIN Retype pending input at next read or input char + TOSTOP Send SIGTTOU for background output + + Canonical input is line-oriented. Input characters are put + into a buffer which can be edited interactively by the user + until a CR (carriage return) or LF (line feed) character is + received. + + Raw input is unprocessed. Input characters are passed + through exactly as they are received, when they are + received. Generally you'll deselect the ICANON, ECHO, + ECHOE, and ISIG options when using raw input + */ + + /* Raw input */ + tios.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG); + + /* C_IFLAG Input options + + Constant Description + INPCK Enable parity check + IGNPAR Ignore parity errors + PARMRK Mark parity errors + ISTRIP Strip parity bits + IXON Enable software flow control (outgoing) + IXOFF Enable software flow control (incoming) + IXANY Allow any character to start flow again + IGNBRK Ignore break condition + BRKINT Send a SIGINT when a break condition is detected + INLCR Map NL to CR + IGNCR Ignore CR + ICRNL Map CR to NL + IUCLC Map uppercase to lowercase + IMAXBEL Echo BEL on input line too long + */ + if (ctx_rtu->parity == 'N') { + /* None */ + tios.c_iflag &= ~INPCK; + } else { + tios.c_iflag |= INPCK; + } + + /* Software flow control is disabled */ + tios.c_iflag &= ~(IXON | IXOFF | IXANY); + + /* C_OFLAG Output options + OPOST Postprocess output (not set = raw output) + ONLCR Map NL to CR-NL + + ONCLR ant others needs OPOST to be enabled + */ + + /* Raw ouput */ + tios.c_oflag &=~ OPOST; + + /* C_CC Control characters + VMIN Minimum number of characters to read + VTIME Time to wait for data (tenths of seconds) + + UNIX serial interface drivers provide the ability to + specify character and packet timeouts. Two elements of the + c_cc array are used for timeouts: VMIN and VTIME. Timeouts + are ignored in canonical input mode or when the NDELAY + option is set on the file via open or fcntl. + + VMIN specifies the minimum number of characters to read. If + it is set to 0, then the VTIME value specifies the time to + wait for every character read. Note that this does not mean + that a read call for N bytes will wait for N characters to + come in. Rather, the timeout will apply to the first + character and the read call will return the number of + characters immediately available (up to the number you + request). + + If VMIN is non-zero, VTIME specifies the time to wait for + the first character read. If a character is read within the + time given, any read will block (wait) until all VMIN + characters are read. That is, once the first character is + read, the serial interface driver expects to receive an + entire packet of characters (VMIN bytes total). If no + character is read within the time allowed, then the call to + read returns 0. This method allows you to tell the serial + driver you need exactly N bytes and any read call will + return 0 or N bytes. However, the timeout only applies to + the first character read, so if for some reason the driver + misses one character inside the N byte packet then the read + call could block forever waiting for additional input + characters. + + VTIME specifies the amount of time to wait for incoming + characters in tenths of seconds. If VTIME is set to 0 (the + default), reads will block (wait) indefinitely unless the + NDELAY option is set on the port with open or fcntl. + */ + /* Unused because we use open with the NDELAY option */ + tios.c_cc[VMIN] = 0; + tios.c_cc[VTIME] = 10; // Set per default to 1 second + + if (tcsetattr(ctx->s, TCSANOW, &tios) < 0) { + close(ctx->s); + ctx->s = -1; + return -1; + } + return 0; +} + +int modbus_rtu_set_serial_mode(modbus_t *ctx, int mode) +{ + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + if (ctx->backend->backend_type == _MODBUS_BACKEND_TYPE_RTU) { +#if HAVE_DECL_TIOCSRS485 + modbus_rtu_t *ctx_rtu = ctx->backend_data; + struct serial_rs485 rs485conf; + memset(&rs485conf, 0x0, sizeof(struct serial_rs485)); + + if (mode == MODBUS_RTU_RS485) { + rs485conf.flags = SER_RS485_ENABLED; + if (ioctl(ctx->s, TIOCSRS485, &rs485conf) < 0) { + return -1; + } + + ctx_rtu->serial_mode = MODBUS_RTU_RS485; + return 0; + } else if (mode == MODBUS_RTU_RS232) { + /* Turn off RS485 mode only if required */ + if (ctx_rtu->serial_mode == MODBUS_RTU_RS485) { + /* The ioctl call is avoided because it can fail on some RS232 ports */ + if (ioctl(ctx->s, TIOCSRS485, &rs485conf) < 0) { + return -1; + } + } + ctx_rtu->serial_mode = MODBUS_RTU_RS232; + return 0; + } +#else + if (ctx->debug) { + fprintf(stderr, "This function isn't supported on your platform\n"); + } + errno = ENOTSUP; + return -1; +#endif + } + + /* Wrong backend and invalid mode specified */ + errno = EINVAL; + return -1; +} + +int modbus_rtu_get_serial_mode(modbus_t *ctx) +{ + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + if (ctx->backend->backend_type == _MODBUS_BACKEND_TYPE_RTU) { +#if HAVE_DECL_TIOCSRS485 + modbus_rtu_t *ctx_rtu = ctx->backend_data; + return ctx_rtu->serial_mode; +#else + if (ctx->debug) { + fprintf(stderr, "This function isn't supported on your platform\n"); + } + errno = ENOTSUP; + return -1; +#endif + } else { + errno = EINVAL; + return -1; + } +} + +int modbus_rtu_get_rts(modbus_t *ctx) +{ + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + if (ctx->backend->backend_type == _MODBUS_BACKEND_TYPE_RTU) { +#if HAVE_DECL_TIOCM_RTS + modbus_rtu_t *ctx_rtu = ctx->backend_data; + return ctx_rtu->rts; +#else + if (ctx->debug) { + fprintf(stderr, "This function isn't supported on your platform\n"); + } + errno = ENOTSUP; + return -1; +#endif + } else { + errno = EINVAL; + return -1; + } +} + +int modbus_rtu_set_rts(modbus_t *ctx, int mode) +{ + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + if (ctx->backend->backend_type == _MODBUS_BACKEND_TYPE_RTU) { +#if HAVE_DECL_TIOCM_RTS + modbus_rtu_t *ctx_rtu = ctx->backend_data; + + if (mode == MODBUS_RTU_RTS_NONE || mode == MODBUS_RTU_RTS_UP || + mode == MODBUS_RTU_RTS_DOWN) { + ctx_rtu->rts = mode; + + /* Set the RTS bit in order to not reserve the RS485 bus */ + ctx_rtu->set_rts(ctx, ctx_rtu->rts != MODBUS_RTU_RTS_UP); + + return 0; + } else { + errno = EINVAL; + return -1; + } +#else + if (ctx->debug) { + fprintf(stderr, "This function isn't supported on your platform\n"); + } + errno = ENOTSUP; + return -1; +#endif + } + /* Wrong backend or invalid mode specified */ + errno = EINVAL; + return -1; +} + +int modbus_rtu_set_custom_rts(modbus_t *ctx, void (*set_rts) (modbus_t *ctx, int on)) +{ + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + if (ctx->backend->backend_type == _MODBUS_BACKEND_TYPE_RTU) { +#if HAVE_DECL_TIOCM_RTS + modbus_rtu_t *ctx_rtu = ctx->backend_data; + ctx_rtu->set_rts = set_rts; + return 0; +#else + if (ctx->debug) { + fprintf(stderr, "This function isn't supported on your platform\n"); + } + errno = ENOTSUP; + return -1; +#endif + } else { + errno = EINVAL; + return -1; + } +} + +int modbus_rtu_get_rts_delay(modbus_t *ctx) +{ + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + if (ctx->backend->backend_type == _MODBUS_BACKEND_TYPE_RTU) { +#if HAVE_DECL_TIOCM_RTS + modbus_rtu_t *ctx_rtu; + ctx_rtu = (modbus_rtu_t *)ctx->backend_data; + return ctx_rtu->rts_delay; +#else + if (ctx->debug) { + fprintf(stderr, "This function isn't supported on your platform\n"); + } + errno = ENOTSUP; + return -1; +#endif + } else { + errno = EINVAL; + return -1; + } +} + +int modbus_rtu_set_rts_delay(modbus_t *ctx, int us) +{ + if (ctx == NULL || us < 0) { + errno = EINVAL; + return -1; + } + + if (ctx->backend->backend_type == _MODBUS_BACKEND_TYPE_RTU) { +#if HAVE_DECL_TIOCM_RTS + modbus_rtu_t *ctx_rtu; + ctx_rtu = (modbus_rtu_t *)ctx->backend_data; + ctx_rtu->rts_delay = us; + return 0; +#else + if (ctx->debug) { + fprintf(stderr, "This function isn't supported on your platform\n"); + } + errno = ENOTSUP; + return -1; +#endif + } else { + errno = EINVAL; + return -1; + } +} + +static void _modbus_rtu_close(modbus_t *ctx) +{ + /* Restore line settings and close file descriptor in RTU mode */ + modbus_rtu_t *ctx_rtu = ctx->backend_data; + + if (ctx->s != -1) { + tcsetattr(ctx->s, TCSANOW, &ctx_rtu->old_tios); + close(ctx->s); + ctx->s = -1; + } +} + +static int _modbus_rtu_flush(modbus_t *ctx) +{ + return tcflush(ctx->s, TCIOFLUSH); +} + +static int _modbus_rtu_select(modbus_t *ctx, fd_set *rset, struct timeval *tv, int length_to_read) +{ + int s_rc; + while ((s_rc = select(ctx->s+1, rset, NULL, NULL, tv)) == -1) + { + if (errno == EINTR) + { + if (ctx->debug) + { + fprintf(stderr, "A non blocked signal was caught\n"); + } + /* Necessary after an error */ + FD_ZERO(rset); + FD_SET(ctx->s, rset); + } + else + { + return -1; + } + } + + if (s_rc == 0) { + /* Timeout */ + errno = ETIMEDOUT; + return -1; + } + + return s_rc; +} + +static void _modbus_rtu_free(modbus_t *ctx) { + free(((modbus_rtu_t*)ctx->backend_data)->device); + free(ctx->backend_data); + free(ctx); +} + +const modbus_backend_t _modbus_rtu_backend = { + _MODBUS_BACKEND_TYPE_RTU, + _MODBUS_RTU_HEADER_LENGTH, + _MODBUS_RTU_CHECKSUM_LENGTH, + MODBUS_RTU_MAX_ADU_LENGTH, + _modbus_set_slave, + _modbus_rtu_build_request_basis, + _modbus_rtu_build_response_basis, + _modbus_rtu_prepare_response_tid, + _modbus_rtu_send_msg_pre, + _modbus_rtu_send, + _modbus_rtu_receive, + _modbus_rtu_recv, + _modbus_rtu_check_integrity, + _modbus_rtu_pre_check_confirmation, + _modbus_rtu_connect, + _modbus_rtu_close, + _modbus_rtu_flush, + _modbus_rtu_select, + _modbus_rtu_free +}; + +modbus_t* modbus_new_rtu(const char *device, + int baud, char parity, int data_bit, + int stop_bit) +{ + modbus_t *ctx; + modbus_rtu_t *ctx_rtu; + + /* Check device argument */ + if (device == NULL || *device == 0) { + fprintf(stderr, "The device string is empty\n"); + errno = EINVAL; + return NULL; + } + + /* Check baud argument */ + if (baud == 0) { + fprintf(stderr, "The baud rate value must not be zero\n"); + errno = EINVAL; + return NULL; + } + + ctx = (modbus_t *)malloc(sizeof(modbus_t)); + _modbus_init_common(ctx); + ctx->backend = &_modbus_rtu_backend; + ctx->backend_data = (modbus_rtu_t *)malloc(sizeof(modbus_rtu_t)); + ctx_rtu = (modbus_rtu_t *)ctx->backend_data; + ctx_rtu->device = NULL; + + /* Device name and \0 */ + ctx_rtu->device = (char *)malloc((strlen(device) + 1) * sizeof(char)); + strcpy(ctx_rtu->device, device); + + ctx_rtu->baud = baud; + if (parity == 'N' || parity == 'E' || parity == 'O') { + ctx_rtu->parity = parity; + } else { + modbus_free(ctx); + errno = EINVAL; + return NULL; + } + ctx_rtu->data_bit = data_bit; + ctx_rtu->stop_bit = stop_bit; + +#if HAVE_DECL_TIOCSRS485 + /* The RS232 mode has been set by default */ + ctx_rtu->serial_mode = MODBUS_RTU_RS232; +#endif + +#if HAVE_DECL_TIOCM_RTS + /* The RTS use has been set by default */ + ctx_rtu->rts = MODBUS_RTU_RTS_NONE; + + /* Calculate estimated time in micro second to send one byte */ + ctx_rtu->onebyte_time = 1000000 * (1 + data_bit + (parity == 'N' ? 0 : 1) + stop_bit) / baud; + + /* The internal function is used by default to set RTS */ + ctx_rtu->set_rts = _modbus_rtu_ioctl_rts; + + /* The delay before and after transmission when toggling the RTS pin */ + ctx_rtu->rts_delay = ctx_rtu->onebyte_time; +#endif + + ctx_rtu->confirmation_to_ignore = FALSE; + + return ctx; +} diff --git a/stack/modbus-rtu.h b/stack/modbus-rtu.h new file mode 100644 index 0000000..e6d22b9 --- /dev/null +++ b/stack/modbus-rtu.h @@ -0,0 +1,34 @@ + +#pragma once + +#include "modbus.h" + +MODBUS_BEGIN_DECLS + +/* Modbus_Application_Protocol_V1_1b.pdf Chapter 4 Section 1 Page 5 + * RS232 / RS485 ADU = 253 bytes + slave (1 byte) + CRC (2 bytes) = 256 bytes + */ +#define MODBUS_RTU_MAX_ADU_LENGTH 256 + +MODBUS_API modbus_t* modbus_new_rtu(const char *device, int baud, char parity, int data_bit, int stop_bit); + +#define MODBUS_RTU_RS232 0 +#define MODBUS_RTU_RS485 1 + +MODBUS_API int modbus_rtu_set_serial_mode( modbus_t *ctx, int mode ); +MODBUS_API int modbus_rtu_get_serial_mode( modbus_t *ctx ); + +#define MODBUS_RTU_RTS_NONE 0 +#define MODBUS_RTU_RTS_UP 1 +#define MODBUS_RTU_RTS_DOWN 2 + +MODBUS_API int modbus_rtu_set_rts( modbus_t *ctx, int mode ); +MODBUS_API int modbus_rtu_get_rts( modbus_t *ctx ); + +MODBUS_API int modbus_rtu_set_custom_rts( modbus_t *ctx, void ( *set_rts ) ( modbus_t *ctx, int on ) ); + +MODBUS_API int modbus_rtu_set_rts_delay( modbus_t *ctx, int us ); +MODBUS_API int modbus_rtu_get_rts_delay( modbus_t *ctx ); + +MODBUS_END_DECLS + diff --git a/stack/modbus-tcp-private.h b/stack/modbus-tcp-private.h new file mode 100644 index 0000000..af340ab --- /dev/null +++ b/stack/modbus-tcp-private.h @@ -0,0 +1,39 @@ +#pragma once + +#define _MODBUS_TCP_HEADER_LENGTH 7 +#define _MODBUS_TCP_PRESET_REQ_LENGTH 12 +#define _MODBUS_TCP_PRESET_RSP_LENGTH 8 + +#define _MODBUS_TCP_CHECKSUM_LENGTH 0 + +/* In both structures, the transaction ID must be placed on first position + to have a quick access not dependant of the TCP backend */ +typedef struct _modbus_tcp +{ + /* Extract from MODBUS Messaging on TCP/IP Implementation Guide V1.0b + (page 23/46): + The transaction identifier is used to associate the future response + with the request. This identifier is unique on each TCP connection. */ + uint16_t t_id; + /* TCP port */ + int port; + /* IP address */ + char ip[16]; +} modbus_tcp_t; + +#define _MODBUS_TCP_PI_NODE_LENGTH 1025 +#define _MODBUS_TCP_PI_SERVICE_LENGTH 32 + +typedef struct _modbus_tcp_pi +{ + /* Transaction ID */ + uint16_t t_id; + /* TCP port */ + int port; + /* Node */ + char node[_MODBUS_TCP_PI_NODE_LENGTH]; + /* Service */ + char service[_MODBUS_TCP_PI_SERVICE_LENGTH]; +} modbus_tcp_pi_t; + + diff --git a/stack/modbus-tcp.c b/stack/modbus-tcp.c new file mode 100644 index 0000000..861757e --- /dev/null +++ b/stack/modbus-tcp.c @@ -0,0 +1,866 @@ + +#include +#include +#include +#include +#include +#include +#include + +# include +# include + +#if defined(__OpenBSD__) || (defined(__FreeBSD__) && __FreeBSD__ < 5) +# define OS_BSD +# include +#endif + +# include +# include +# include +# include +# include + +#if !defined(MSG_NOSIGNAL) +#define MSG_NOSIGNAL 0 +#endif + +#include "modbus-private.h" + +#include "modbus-tcp.h" +#include "modbus-tcp-private.h" + +static int _modbus_set_slave(modbus_t *ctx, int slave) +{ + /* Broadcast address is 0 (MODBUS_BROADCAST_ADDRESS) */ + if ( slave >= 0 && slave <= 247) + { + ctx->slave = slave; + } + else if ( slave == MODBUS_TCP_SLAVE ) + { + /* The special value MODBUS_TCP_SLAVE (0xFF) can be used in TCP mode to + * restore the default value. */ + ctx->slave = slave; + } + else + { + errno = EINVAL; + return -1; + } + + return 0; +} + +/* Builds a TCP request header */ +static int _modbus_tcp_build_request_basis( modbus_t *ctx, int function, int addr, int nb, uint8_t *req ) +{ + modbus_tcp_t *ctx_tcp = ctx->backend_data; + + /* Increase transaction ID */ + if (ctx_tcp->t_id < UINT16_MAX) + ctx_tcp->t_id++; + else + ctx_tcp->t_id = 0; + + req[0] = ctx_tcp->t_id >> 8; + req[1] = ctx_tcp->t_id & 0x00ff; + + /* Protocol Modbus */ + req[2] = 0; + req[3] = 0; + + /* Length will be defined later by set_req_length_tcp at offsets 4 + and 5 */ + + req[6] = ctx->slave; + req[7] = function; + req[8] = addr >> 8; + req[9] = addr & 0x00ff; + req[10] = nb >> 8; + req[11] = nb & 0x00ff; + + return _MODBUS_TCP_PRESET_REQ_LENGTH; +} + +/* Builds a TCP response header */ +static int _modbus_tcp_build_response_basis( sft_t *sft, uint8_t *rsp ) +{ + /* Extract from MODBUS Messaging on TCP/IP Implementation + Guide V1.0b (page 23/46): + The transaction identifier is used to associate the future + response with the request. */ + rsp[0] = sft->t_id >> 8; + rsp[1] = sft->t_id & 0x00ff; + + /* Protocol Modbus */ + rsp[2] = 0; + rsp[3] = 0; + + /* Length will be set later by send_msg (4 and 5) */ + + /* The slave ID is copied from the indication */ + rsp[6] = sft->slave; + rsp[7] = sft->function; + + return _MODBUS_TCP_PRESET_RSP_LENGTH; +} + + +static int _modbus_tcp_prepare_response_tid( const uint8_t *req, int *req_length ) +{ + return (req[0] << 8) + req[1]; +} + +static int _modbus_tcp_send_msg_pre( uint8_t *req, int req_length ) +{ + /* Substract the header length to the message length */ + int mbap_length = req_length - 6; + + req[4] = mbap_length >> 8; + req[5] = mbap_length & 0x00FF; + + return req_length; +} + +static ssize_t _modbus_tcp_send( modbus_t *ctx, const uint8_t *req, int req_length ) +{ + /* MSG_NOSIGNAL + Requests not to send SIGPIPE on errors on stream oriented + sockets when the other end breaks the connection. The EPIPE + error is still returned. */ + return send(ctx->s, (const char *)req, req_length, MSG_NOSIGNAL); +} + +static int _modbus_tcp_receive(modbus_t *ctx, uint8_t *req) +{ + return _modbus_receive_msg(ctx, req, MSG_INDICATION); +} + +static ssize_t _modbus_tcp_recv(modbus_t *ctx, uint8_t *rsp, int rsp_length) +{ + return recv( ctx->s, (char *)rsp, rsp_length, 0 ); +} + +static int _modbus_tcp_check_integrity( modbus_t *ctx, uint8_t *msg, const int msg_length ) +{ + return msg_length; +} + +static int _modbus_tcp_pre_check_confirmation( modbus_t *ctx, const uint8_t *req, const uint8_t *rsp, int rsp_length ) +{ + /* Check transaction ID */ + if (req[0] != rsp[0] || req[1] != rsp[1]) { + if (ctx->debug) + { + fprintf(stderr, "Invalid transaction ID received 0x%X (not 0x%X)\n", + (rsp[0] << 8) + rsp[1], (req[0] << 8) + req[1]); + } + errno = EMBBADDATA; + return -1; + } + + /* Check protocol ID */ + if (rsp[2] != 0x0 && rsp[3] != 0x0) + { + if (ctx->debug) + { + fprintf(stderr, "Invalid protocol ID received 0x%X (not 0x0)\n", + (rsp[2] << 8) + rsp[3]); + } + errno = EMBBADDATA; + return -1; + } + + return 0; +} + +static int _modbus_tcp_set_ipv4_options( int s ) +{ + int rc; + int option; + + /* Set the TCP no delay flag */ + /* SOL_TCP = IPPROTO_TCP */ + option = 1; + rc = setsockopt(s, IPPROTO_TCP, TCP_NODELAY, (const void *)&option, sizeof(int) ); + if (rc == -1) + { + return -1; + } + + /* If the OS does not offer SOCK_NONBLOCK, fall back to setting FIONBIO to + * make sockets non-blocking */ + /* Do not care about the return value, this is optional */ +#if !defined(SOCK_NONBLOCK) && defined(FIONBIO) + option = 1; + ioctl(s, FIONBIO, &option); +#endif + + /** + * Cygwin defines IPTOS_LOWDELAY but can't handle that flag so it's + * necessary to workaround that problem. + **/ + /* Set the IP low delay option */ + option = IPTOS_LOWDELAY; + rc = setsockopt(s, IPPROTO_IP, IP_TOS, + (const void *)&option, sizeof(int)); + if (rc == -1) { + return -1; + } + + return 0; +} + +static int _connect( int sockfd, const struct sockaddr *addr, socklen_t addrlen, const struct timeval *ro_tv ) +{ + int rc = connect(sockfd, addr, addrlen); + + if (rc == -1 && errno == EINPROGRESS) + { + fd_set wset; + int optval; + socklen_t optlen = sizeof(optval); + struct timeval tv = *ro_tv; + + /* Wait to be available in writing */ + FD_ZERO(&wset); + FD_SET(sockfd, &wset); + rc = select(sockfd + 1, NULL, &wset, NULL, &tv); + if (rc <= 0) + { + /* Timeout or fail */ + return -1; + } + + /* The connection is established if SO_ERROR and optval are set to 0 */ + rc = getsockopt(sockfd, SOL_SOCKET, SO_ERROR, (void *)&optval, &optlen); + if ( rc == 0 && optval == 0 ) + { + return 0; + } + else + { + errno = ECONNREFUSED; + return -1; + } + } + return rc; +} + +/* Establishes a modbus TCP connection with a Modbus server. */ +static int _modbus_tcp_connect( modbus_t *ctx ) +{ + int rc; + /* Specialized version of sockaddr for Internet socket address (same size) */ + struct sockaddr_in addr; + modbus_tcp_t *ctx_tcp = ctx->backend_data; + int flags = SOCK_STREAM; + +#ifdef SOCK_CLOEXEC + flags |= SOCK_CLOEXEC; +#endif + +#ifdef SOCK_NONBLOCK + flags |= SOCK_NONBLOCK; +#endif + + ctx->s = socket(PF_INET, flags, 0); + if (ctx->s == -1) + { + return -1; + } + + rc = _modbus_tcp_set_ipv4_options(ctx->s); + if (rc == -1) + { + close(ctx->s); + ctx->s = -1; + return -1; + } + + if (ctx->debug) + { + printf("Connecting to %s:%d\n", ctx_tcp->ip, ctx_tcp->port); + } + + addr.sin_family = AF_INET; + addr.sin_port = htons(ctx_tcp->port); + addr.sin_addr.s_addr = inet_addr(ctx_tcp->ip); + rc = _connect(ctx->s, (struct sockaddr *)&addr, sizeof(addr), &ctx->response_timeout); + if( rc == -1 ) + { + close( ctx->s ); + ctx->s = -1; + return -1; + } + + return 0; +} + +/* Establishes a modbus TCP PI connection with a Modbus server. */ +static int _modbus_tcp_pi_connect( modbus_t *ctx ) +{ + int rc; + struct addrinfo *ai_list; + struct addrinfo *ai_ptr; + struct addrinfo ai_hints; + modbus_tcp_pi_t *ctx_tcp_pi = ctx->backend_data; + + memset(&ai_hints, 0, sizeof(ai_hints)); +#ifdef AI_ADDRCONFIG + ai_hints.ai_flags |= AI_ADDRCONFIG; +#endif + ai_hints.ai_family = AF_UNSPEC; + ai_hints.ai_socktype = SOCK_STREAM; + ai_hints.ai_addr = NULL; + ai_hints.ai_canonname = NULL; + ai_hints.ai_next = NULL; + + ai_list = NULL; + rc = getaddrinfo(ctx_tcp_pi->node, ctx_tcp_pi->service, &ai_hints, &ai_list); + if (rc != 0) + { + if (ctx->debug) + { + fprintf(stderr, "Error returned by getaddrinfo: %s\n", gai_strerror(rc)); + } + errno = ECONNREFUSED; + return -1; + } + + for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next) + { + int flags = ai_ptr->ai_socktype; + int s; + +#ifdef SOCK_CLOEXEC + flags |= SOCK_CLOEXEC; +#endif + +#ifdef SOCK_NONBLOCK + flags |= SOCK_NONBLOCK; +#endif + + s = socket(ai_ptr->ai_family, flags, ai_ptr->ai_protocol); + if (s < 0) + continue; + + if (ai_ptr->ai_family == AF_INET) + _modbus_tcp_set_ipv4_options(s); + + if (ctx->debug) + { + printf("Connecting to [%s]:%s\n", ctx_tcp_pi->node, ctx_tcp_pi->service); + } + + rc = _connect(s, ai_ptr->ai_addr, ai_ptr->ai_addrlen, &ctx->response_timeout); + if (rc == -1) + { + close(s); + continue; + } + + ctx->s = s; + break; + } + + freeaddrinfo(ai_list); + + if (ctx->s < 0) + { + return -1; + } + + return 0; +} + +/* Closes the network connection and socket in TCP mode */ +static void _modbus_tcp_close( modbus_t *ctx ) +{ + if (ctx->s != -1) + { + shutdown(ctx->s, SHUT_RDWR); + close(ctx->s); + ctx->s = -1; + } +} + +static int _modbus_tcp_flush( modbus_t *ctx ) +{ + int rc; + int rc_sum = 0; + + do + { + /* Extract the garbage from the socket */ + char devnull[MODBUS_TCP_MAX_ADU_LENGTH]; + + rc = recv(ctx->s, devnull, MODBUS_TCP_MAX_ADU_LENGTH, MSG_DONTWAIT); + if ( rc > 0 ) + { + rc_sum += rc; + } + } while ( rc == MODBUS_TCP_MAX_ADU_LENGTH ); + + return rc_sum; +} + +/* Listens for any request from one or many modbus masters in TCP */ +int modbus_tcp_listen( modbus_t *ctx, int nb_connection ) +{ + int new_s; + int enable; + struct sockaddr_in addr; + modbus_tcp_t *ctx_tcp; + + if (ctx == NULL) + { + errno = EINVAL; + return -1; + } + + ctx_tcp = ctx->backend_data; + + new_s = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP); + if ( new_s == -1 ) + { + return -1; + } + + enable = 1; + if (setsockopt(new_s, SOL_SOCKET, SO_REUSEADDR, (char *)&enable, sizeof(enable)) == -1) + { + close(new_s); + return -1; + } + + memset(&addr, 0, sizeof(addr)); + addr.sin_family = AF_INET; + + /* If the modbus port is < to 1024, we need the setuid root. */ + addr.sin_port = htons(ctx_tcp->port); + if (ctx_tcp->ip[0] == '0') + { + /* Listen any addresses */ + addr.sin_addr.s_addr = htonl(INADDR_ANY); + } + else + { + /* Listen only specified IP address */ + addr.sin_addr.s_addr = inet_addr(ctx_tcp->ip); + } + if (bind( new_s, (struct sockaddr *)&addr, sizeof(addr)) == -1) + { + close(new_s); + return -1; + } + + if (listen(new_s, nb_connection) == -1) + { + close(new_s); + return -1; + } + + return new_s; +} + +int modbus_tcp_pi_listen( modbus_t *ctx, int nb_connection ) +{ + int rc; + struct addrinfo *ai_list; + struct addrinfo *ai_ptr; + struct addrinfo ai_hints; + const char *node; + const char *service; + int new_s; + modbus_tcp_pi_t *ctx_tcp_pi; + + if (ctx == NULL) + { + errno = EINVAL; + return -1; + } + + ctx_tcp_pi = ctx->backend_data; + + if ( ctx_tcp_pi->node[0] == 0) + { + node = NULL; /* == any */ + } + else + { + node = ctx_tcp_pi->node; + } + + if ( ctx_tcp_pi->service[0] == 0 ) + { + service = "502"; + } + else + { + service = ctx_tcp_pi->service; + } + + memset( &ai_hints, 0, sizeof (ai_hints) ); + /* If node is not NULL, than the AI_PASSIVE flag is ignored. */ + ai_hints.ai_flags |= AI_PASSIVE; +#ifdef AI_ADDRCONFIG + ai_hints.ai_flags |= AI_ADDRCONFIG; +#endif + ai_hints.ai_family = AF_UNSPEC; + ai_hints.ai_socktype = SOCK_STREAM; + ai_hints.ai_addr = NULL; + ai_hints.ai_canonname = NULL; + ai_hints.ai_next = NULL; + + ai_list = NULL; + rc = getaddrinfo(node, service, &ai_hints, &ai_list); + if (rc != 0) + { + if (ctx->debug) + { + fprintf(stderr, "Error returned by getaddrinfo: %s\n", gai_strerror(rc)); + } + errno = ECONNREFUSED; + return -1; + } + + new_s = -1; + for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next) + { + int s; + + s = socket( ai_ptr->ai_family, ai_ptr->ai_socktype, ai_ptr->ai_protocol ); + if (s < 0) + { + if (ctx->debug) + { + perror("socket"); + } + continue; + } + else + { + int enable = 1; + rc = setsockopt( s, SOL_SOCKET, SO_REUSEADDR, (void *)&enable, sizeof (enable) ); + if (rc != 0) + { + close(s); + if (ctx->debug) + { + perror("setsockopt"); + } + continue; + } + } + + rc = bind(s, ai_ptr->ai_addr, ai_ptr->ai_addrlen); + if (rc != 0) + { + close(s); + if (ctx->debug) + { + perror("bind"); + } + continue; + } + + rc = listen(s, nb_connection); + if (rc != 0) + { + close(s); + if (ctx->debug) + { + perror("listen"); + } + continue; + } + + new_s = s; + break; + } + freeaddrinfo(ai_list); + + if (new_s < 0) + { + return -1; + } + + return new_s; +} + +int modbus_tcp_accept(modbus_t *ctx, int *s) +{ + struct sockaddr_in addr; + socklen_t addrlen; + + if (ctx == NULL) + { + errno = EINVAL; + return -1; + } + + addrlen = sizeof(addr); +#ifdef HAVE_ACCEPT4 + /* Inherit socket flags and use accept4 call */ + ctx->s = accept4(*s, (struct sockaddr *)&addr, &addrlen, SOCK_CLOEXEC); +#else + ctx->s = accept(*s, (struct sockaddr *)&addr, &addrlen); +#endif + + if (ctx->s == -1) + { + close(*s); + *s = -1; + return -1; + } + + if (ctx->debug) + { + printf("The client connection from %s is accepted\n", + inet_ntoa(addr.sin_addr)); + } + + return ctx->s; +} + +int modbus_tcp_pi_accept( modbus_t *ctx, int *s ) +{ + struct sockaddr_storage addr; + socklen_t addrlen; + + if (ctx == NULL) + { + errno = EINVAL; + return -1; + } + + addrlen = sizeof(addr); +#ifdef HAVE_ACCEPT4 + /* Inherit socket flags and use accept4 call */ + ctx->s = accept4(*s, (struct sockaddr *)&addr, &addrlen, SOCK_CLOEXEC); +#else + ctx->s = accept(*s, (struct sockaddr *)&addr, &addrlen); +#endif + if (ctx->s == -1) + { + close(*s); + *s = -1; + } + + if (ctx->debug) + { + printf("The client connection is accepted.\n"); + } + + return ctx->s; +} + +static int _modbus_tcp_select(modbus_t *ctx, fd_set *rset, struct timeval *tv, int length_to_read) +{ + int s_rc; + while ((s_rc = select(ctx->s+1, rset, NULL, NULL, tv)) == -1) + { + if (errno == EINTR) + { + if (ctx->debug) + { + fprintf(stderr, "A non blocked signal was caught\n"); + } + /* Necessary after an error */ + FD_ZERO(rset); + FD_SET(ctx->s, rset); + } + else + { + return -1; + } + } + + if ( s_rc == 0 ) + { + errno = ETIMEDOUT; + return -1; + } + + return s_rc; +} + +static void _modbus_tcp_free( modbus_t *ctx ) +{ + free(ctx->backend_data); + free(ctx); +} + +const modbus_backend_t _modbus_tcp_backend = +{ + _MODBUS_BACKEND_TYPE_TCP, + _MODBUS_TCP_HEADER_LENGTH, + _MODBUS_TCP_CHECKSUM_LENGTH, + MODBUS_TCP_MAX_ADU_LENGTH, + _modbus_set_slave, + _modbus_tcp_build_request_basis, + _modbus_tcp_build_response_basis, + _modbus_tcp_prepare_response_tid, + _modbus_tcp_send_msg_pre, + _modbus_tcp_send, + _modbus_tcp_receive, + _modbus_tcp_recv, + _modbus_tcp_check_integrity, + _modbus_tcp_pre_check_confirmation, + _modbus_tcp_connect, + _modbus_tcp_close, + _modbus_tcp_flush, + _modbus_tcp_select, + _modbus_tcp_free +}; + + +const modbus_backend_t _modbus_tcp_pi_backend = +{ + _MODBUS_BACKEND_TYPE_TCP, + _MODBUS_TCP_HEADER_LENGTH, + _MODBUS_TCP_CHECKSUM_LENGTH, + MODBUS_TCP_MAX_ADU_LENGTH, + _modbus_set_slave, + _modbus_tcp_build_request_basis, + _modbus_tcp_build_response_basis, + _modbus_tcp_prepare_response_tid, + _modbus_tcp_send_msg_pre, + _modbus_tcp_send, + _modbus_tcp_receive, + _modbus_tcp_recv, + _modbus_tcp_check_integrity, + _modbus_tcp_pre_check_confirmation, + _modbus_tcp_pi_connect, + _modbus_tcp_close, + _modbus_tcp_flush, + _modbus_tcp_select, + _modbus_tcp_free +}; + +modbus_t* modbus_new_tcp( const char *ip, int port ) +{ + modbus_t *ctx; + modbus_tcp_t *ctx_tcp; + size_t dest_size; + size_t ret_size; + + ctx = (modbus_t *)malloc(sizeof(modbus_t) ); + _modbus_init_common(ctx); + + /* Could be changed after to reach a remote serial Modbus device */ + ctx->slave = MODBUS_TCP_SLAVE; + + ctx->backend = &_modbus_tcp_backend; + + ctx->backend_data = ( modbus_tcp_t *)malloc(sizeof(modbus_tcp_t) ); + ctx_tcp = (modbus_tcp_t *)ctx->backend_data; + + if (ip != NULL) + { + dest_size = sizeof(char) * 16; + ret_size = strlcpy(ctx_tcp->ip, ip, dest_size); + if (ret_size == 0) + { + fprintf(stderr, "The IP string is empty\n"); + modbus_free(ctx); + errno = EINVAL; + return NULL; + } + + if (ret_size >= dest_size) + { + fprintf(stderr, "The IP string has been truncated\n"); + modbus_free(ctx); + errno = EINVAL; + return NULL; + } + } + else + { + ctx_tcp->ip[0] = '0'; + } + ctx_tcp->port = port; + ctx_tcp->t_id = 0; + + return ctx; +} + + +modbus_t* modbus_new_tcp_pi( const char *node, const char *service ) +{ + modbus_t *ctx; + modbus_tcp_pi_t *ctx_tcp_pi; + size_t dest_size; + size_t ret_size; + + ctx = (modbus_t *)malloc(sizeof(modbus_t)); + _modbus_init_common(ctx); + + /* Could be changed after to reach a remote serial Modbus device */ + ctx->slave = MODBUS_TCP_SLAVE; + + ctx->backend = &_modbus_tcp_pi_backend; + + ctx->backend_data = (modbus_tcp_pi_t *)malloc(sizeof(modbus_tcp_pi_t)); + ctx_tcp_pi = (modbus_tcp_pi_t *)ctx->backend_data; + + if (node == NULL) + { + /* The node argument can be empty to indicate any hosts */ + ctx_tcp_pi->node[0] = 0; + } + else + { + dest_size = sizeof(char) * _MODBUS_TCP_PI_NODE_LENGTH; + ret_size = strlcpy(ctx_tcp_pi->node, node, dest_size); + if (ret_size == 0) + { + fprintf(stderr, "The node string is empty\n"); + modbus_free(ctx); + errno = EINVAL; + return NULL; + } + + if (ret_size >= dest_size) + { + fprintf(stderr, "The node string has been truncated\n"); + modbus_free(ctx); + errno = EINVAL; + return NULL; + } + } + + if (service != NULL) + { + dest_size = sizeof(char) * _MODBUS_TCP_PI_SERVICE_LENGTH; + ret_size = strlcpy(ctx_tcp_pi->service, service, dest_size); + } + else + { + /* Empty service is not allowed, error catched below. */ + ret_size = 0; + } + + if (ret_size == 0) + { + fprintf(stderr, "The service string is empty\n"); + modbus_free(ctx); + errno = EINVAL; + return NULL; + } + + if (ret_size >= dest_size) + { + fprintf(stderr, "The service string has been truncated\n"); + modbus_free(ctx); + errno = EINVAL; + return NULL; + } + + ctx_tcp_pi->t_id = 0; + + return ctx; +} diff --git a/stack/modbus-tcp.h b/stack/modbus-tcp.h new file mode 100644 index 0000000..c94f545 --- /dev/null +++ b/stack/modbus-tcp.h @@ -0,0 +1,24 @@ +#pragma once + +#include "modbus.h" + +MODBUS_BEGIN_DECLS + +#define MODBUS_TCP_DEFAULT_PORT 502 +#define MODBUS_TCP_SLAVE 0xFF + +/* Modbus_Application_Protocol_V1_1b.pdf Chapter 4 Section 1 Page 5 + * TCP MODBUS ADU = 253 bytes + MBAP (7 bytes) = 260 bytes + */ +#define MODBUS_TCP_MAX_ADU_LENGTH 260 + +MODBUS_API modbus_t* modbus_new_tcp(const char *ip_address, int port); +MODBUS_API int modbus_tcp_listen(modbus_t *ctx, int nb_connection); +MODBUS_API int modbus_tcp_accept(modbus_t *ctx, int *s); + +MODBUS_API modbus_t* modbus_new_tcp_pi(const char *node, const char *service); +MODBUS_API int modbus_tcp_pi_listen(modbus_t *ctx, int nb_connection); +MODBUS_API int modbus_tcp_pi_accept(modbus_t *ctx, int *s); + +MODBUS_END_DECLS + diff --git a/stack/modbus-version.h b/stack/modbus-version.h new file mode 100644 index 0000000..f7d3c48 --- /dev/null +++ b/stack/modbus-version.h @@ -0,0 +1,34 @@ +#pragma once + +/* The major version, (1, if %LIBMODBUS_VERSION is 1.2.3) */ +#define LIBMODBUS_VERSION_MAJOR (3) + +/* The minor version (2, if %LIBMODBUS_VERSION is 1.2.3) */ +#define LIBMODBUS_VERSION_MINOR (1) + +/* The micro version (3, if %LIBMODBUS_VERSION is 1.2.3) */ +#define LIBMODBUS_VERSION_MICRO (4) + +/* The full version, like 1.2.3 */ +#define LIBMODBUS_VERSION 3.1.4 + +/* The full version, in string form (suited for string concatenation) + */ +#define LIBMODBUS_VERSION_STRING "3.1.4" + +/* Numerically encoded version, like 0x010203 */ +#define LIBMODBUS_VERSION_HEX ((LIBMODBUS_VERSION_MAJOR << 24) | \ + (LIBMODBUS_VERSION_MINOR << 16) | \ + (LIBMODBUS_VERSION_MICRO << 8)) + +/* Evaluates to True if the version is greater than @major, @minor and @micro + */ +#define LIBMODBUS_VERSION_CHECK(major,minor,micro) \ + (LIBMODBUS_VERSION_MAJOR > (major) || \ + (LIBMODBUS_VERSION_MAJOR == (major) && \ + LIBMODBUS_VERSION_MINOR > (minor)) || \ + (LIBMODBUS_VERSION_MAJOR == (major) && \ + LIBMODBUS_VERSION_MINOR == (minor) && \ + LIBMODBUS_VERSION_MICRO >= (micro))) + + diff --git a/stack/modbus.c b/stack/modbus.c new file mode 100644 index 0000000..b5a3700 --- /dev/null +++ b/stack/modbus.c @@ -0,0 +1,1898 @@ +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "modbus.h" +#include "modbus-private.h" + +/* Internal use */ +#define MSG_LENGTH_UNDEFINED -1 + +/* Max between RTU and TCP max adu length (so TCP) */ +#define MAX_MESSAGE_LENGTH 260 + +/* 3 steps are used to parse the query */ +typedef enum +{ + _STEP_FUNCTION, + _STEP_META, + _STEP_DATA +} _step_t; + +const char *modbus_strerror( int errnum ) +{ + switch (errnum) + { + case EMBXILFUN: + return "Illegal function"; + case EMBXILADD: + return "Illegal data address"; + case EMBXILVAL: + return "Illegal data value"; + case EMBXSFAIL: + return "Slave device or server failure"; + case EMBXACK: + return "Acknowledge"; + case EMBXSBUSY: + return "Slave device or server is busy"; + case EMBXNACK: + return "Negative acknowledge"; + case EMBXMEMPAR: + return "Memory parity error"; + case EMBXGPATH: + return "Gateway path unavailable"; + case EMBXGTAR: + return "Target device failed to respond"; + case EMBBADCRC: + return "Invalid CRC"; + case EMBBADDATA: + return "Invalid data"; + case EMBBADEXC: + return "Invalid exception code"; + case EMBMDATA: + return "Too many data"; + case EMBBADSLAVE: + return "Response not from requested slave"; + default: + return strerror(errnum); + } +} + +void _error_print(modbus_t *ctx, const char *context) +{ + if (ctx->debug) + { + fprintf(stderr, "ERROR %s", modbus_strerror(errno)); + if (context != NULL) + { + fprintf(stderr, ": %s\n", context); + } + else + { + fprintf(stderr, "\n"); + } + } +} + +static void _sleep_response_timeout(modbus_t *ctx) +{ + /* Response timeout is always positive */ + /* usleep source code */ + struct timespec request, remaining; + request.tv_sec = ctx->response_timeout.tv_sec; + request.tv_nsec = ((long int)ctx->response_timeout.tv_usec) * 1000; + while ( nanosleep( &request, &remaining ) == -1 && errno == EINTR ) + { + request = remaining; + } +} + +int modbus_flush(modbus_t *ctx) +{ + int rc; + + if (ctx == NULL) + { + errno = EINVAL; + return -1; + } + + rc = ctx->backend->flush( ctx ); + if (rc != -1 && ctx->debug) + { + /* Not all backends are able to return the number of bytes flushed */ + printf("Bytes flushed (%d)\n", rc); + } + return rc; +} + +/* Computes the length of the expected response */ +static unsigned int compute_response_length_from_request(modbus_t *ctx, uint8_t *req) +{ + int length; + const int offset = ctx->backend->header_length; + + switch (req[offset]) + { + case MODBUS_FC_READ_COILS: + case MODBUS_FC_READ_DISCRETE_INPUTS: + /* Header + nb values (code from write_bits) */ + int nb = (req[offset + 3] << 8) | req[offset + 4]; + length = 2 + (nb / 8) + ((nb % 8) ? 1 : 0); + break; + case MODBUS_FC_WRITE_AND_READ_REGISTERS: + case MODBUS_FC_READ_HOLDING_REGISTERS: + case MODBUS_FC_READ_INPUT_REGISTERS: + /* Header + 2 * nb values */ + length = 2 + 2 * (req[offset + 3] << 8 | req[offset + 4]); + break; + case MODBUS_FC_READ_EXCEPTION_STATUS: + length = 3; + break; + case MODBUS_FC_REPORT_SLAVE_ID: + /* The response is device specific (the header provides the + length) */ + return MSG_LENGTH_UNDEFINED; + case MODBUS_FC_MASK_WRITE_REGISTER: + length = 7; + break; + default: + length = 5; + } + + return offset + length + ctx->backend->checksum_length; +} + +/* Sends a request/response */ +static int send_msg(modbus_t *ctx, uint8_t *msg, int msg_length) +{ + int rc; + int i; + + msg_length = ctx->backend->send_msg_pre(msg, msg_length); + + if (ctx->debug) + { + for (i = 0; i < msg_length; i++) + { + printf("[%.2X]", msg[i]); + } + printf("\n"); + } + + /* In recovery mode, the write command will be issued until to be + successful! Disabled by default. */ + do + { + rc = ctx->backend->send(ctx, msg, msg_length); + if (rc == -1) + { + _error_print(ctx, NULL); + if (ctx->error_recovery & MODBUS_ERROR_RECOVERY_LINK) + { + int saved_errno = errno; + + if ( (errno == EBADF || errno == ECONNRESET || errno == EPIPE)) + { + modbus_close(ctx); + _sleep_response_timeout(ctx); + modbus_connect(ctx); + } + else + { + _sleep_response_timeout(ctx); + modbus_flush(ctx); + } + errno = saved_errno; + } + } + } while ( (ctx->error_recovery & MODBUS_ERROR_RECOVERY_LINK) && rc == -1); + + if (rc > 0 && rc != msg_length) { + errno = EMBBADDATA; + return -1; + } + + return rc; +} + +int modbus_send_raw_request( modbus_t *ctx, uint8_t *raw_req, int raw_req_length ) +{ + sft_t sft; + uint8_t req[MAX_MESSAGE_LENGTH]; + int req_length; + + if (ctx == NULL) + { + errno = EINVAL; + return -1; + } + + if (raw_req_length < 2 || raw_req_length > (MODBUS_MAX_PDU_LENGTH + 1)) + { + /* The raw request must contain function and slave at least and + must not be longer than the maximum pdu length plus the slave + address. */ + errno = EINVAL; + return -1; + } + + sft.slave = raw_req[0]; + sft.function = raw_req[1]; + /* The t_id is left to zero */ + sft.t_id = 0; + /* This response function only set the header so it's convenient here */ + req_length = ctx->backend->build_response_basis(&sft, req); + + if( raw_req_length > 2 ) + { + /* Copy data after function code */ + memcpy(req + req_length, raw_req + 2, raw_req_length - 2); + req_length += raw_req_length - 2; + } + + return send_msg(ctx, req, req_length); +} + +/* + * ---------- Request Indication ---------- + * | Client | ---------------------->| Server | + * ---------- Confirmation Response ---------- + */ + +/* Computes the length to read after the function received */ +static uint8_t compute_meta_length_after_function( int function, msg_type_t msg_type ) +{ + int length; + + if (msg_type == MSG_INDICATION) + { + if (function <= MODBUS_FC_WRITE_SINGLE_REGISTER) + { + length = 4; + } + else if (function == MODBUS_FC_WRITE_MULTIPLE_COILS || function == MODBUS_FC_WRITE_MULTIPLE_REGISTERS) + { + length = 5; + } + else if (function == MODBUS_FC_MASK_WRITE_REGISTER) + { + length = 6; + } + else if (function == MODBUS_FC_WRITE_AND_READ_REGISTERS) + { + length = 9; + } + else + { + /* MODBUS_FC_READ_EXCEPTION_STATUS, MODBUS_FC_REPORT_SLAVE_ID */ + length = 0; + } + } + else + { + /* MSG_CONFIRMATION */ + switch (function) + { + case MODBUS_FC_WRITE_SINGLE_COIL: + case MODBUS_FC_WRITE_SINGLE_REGISTER: + case MODBUS_FC_WRITE_MULTIPLE_COILS: + case MODBUS_FC_WRITE_MULTIPLE_REGISTERS: + length = 4; + break; + case MODBUS_FC_MASK_WRITE_REGISTER: + length = 6; + break; + default: + length = 1; + } + } + + return length; +} + +/* Computes the length to read after the meta information (address, count, etc) */ +static int compute_data_length_after_meta(modbus_t *ctx, uint8_t *msg, msg_type_t msg_type) +{ + int function = msg[ctx->backend->header_length]; + int length; + + if (msg_type == MSG_INDICATION) + { + switch (function) + { + case MODBUS_FC_WRITE_MULTIPLE_COILS: + case MODBUS_FC_WRITE_MULTIPLE_REGISTERS: + length = msg[ctx->backend->header_length + 5]; + break; + case MODBUS_FC_WRITE_AND_READ_REGISTERS: + length = msg[ctx->backend->header_length + 9]; + break; + default: + length = 0; + } + } + else + { + /* MSG_CONFIRMATION */ + if (function <= MODBUS_FC_READ_INPUT_REGISTERS || + function == MODBUS_FC_REPORT_SLAVE_ID || + function == MODBUS_FC_WRITE_AND_READ_REGISTERS) + { + length = msg[ctx->backend->header_length + 1]; + } + else + { + length = 0; + } + } + + length += ctx->backend->checksum_length; + + return length; +} + + +/* Waits a response from a modbus server or a request from a modbus client. + This function blocks if there is no replies (3 timeouts). + + The function shall return the number of received characters and the received + message in an array of uint8_t if successful. Otherwise it shall return -1 + and errno is set to one of the values defined below: + - ECONNRESET + - EMBBADDATA + - EMBUNKEXC + - ETIMEDOUT + - read() or recv() error codes +*/ + +int _modbus_receive_msg( modbus_t *ctx, uint8_t *msg, msg_type_t msg_type ) +{ + int rc; + fd_set rset; + struct timeval tv; + struct timeval *p_tv; + int length_to_read; + int msg_length = 0; + _step_t step; + + if (ctx->debug) + { + if (msg_type == MSG_INDICATION) + { + printf("Waiting for a indication...\n"); + } + else + { + printf("Waiting for a confirmation...\n"); + } + } + + /* Add a file descriptor to the set */ + FD_ZERO(&rset); + FD_SET(ctx->s, &rset); + + /* We need to analyse the message step by step. At the first step, we want + * to reach the function code because all packets contain this + * information. */ + step = _STEP_FUNCTION; + length_to_read = ctx->backend->header_length + 1; + + if (msg_type == MSG_INDICATION) + { + /* Wait for a message, we don't know when the message will be + * received */ + p_tv = NULL; + } + else + { + tv.tv_sec = ctx->response_timeout.tv_sec; + tv.tv_usec = ctx->response_timeout.tv_usec; + p_tv = &tv; + } + + while (length_to_read != 0) + { + rc = ctx->backend->select(ctx, &rset, p_tv, length_to_read); + if (rc == -1) + { + _error_print(ctx, "select"); + if (ctx->error_recovery & MODBUS_ERROR_RECOVERY_LINK) + { + int saved_errno = errno; + + if (errno == ETIMEDOUT) + { + _sleep_response_timeout(ctx); + modbus_flush(ctx); + } + else if (errno == EBADF) + { + modbus_close(ctx); + modbus_connect(ctx); + } + errno = saved_errno; + } + return -1; + } + + rc = ctx->backend->recv(ctx, msg + msg_length, length_to_read); + if (rc == 0) + { + errno = ECONNRESET; + rc = -1; + } + + if (rc == -1) + { + _error_print(ctx, "read"); + if ((ctx->error_recovery & MODBUS_ERROR_RECOVERY_LINK) && + (errno == ECONNRESET || errno == ECONNREFUSED || + errno == EBADF)) + { + int saved_errno = errno; + modbus_close(ctx); + modbus_connect(ctx); + /* Could be removed by previous calls */ + errno = saved_errno; + } + return -1; + } + + /* Display the hex code of each character received */ + if (ctx->debug) + { + int i; + for (i=0; i < rc; i++) + printf("<%.2X>", msg[msg_length + i]); + } + + /* Sums bytes received */ + msg_length += rc; + /* Computes remaining bytes */ + length_to_read -= rc; + + if (length_to_read == 0) + { + switch (step) + { + case _STEP_FUNCTION: + /* Function code position */ + length_to_read = compute_meta_length_after_function( msg[ctx->backend->header_length], msg_type); + if (length_to_read != 0) + { + step = _STEP_META; + break; + } /* else switches straight to the next step */ + case _STEP_META: + length_to_read = compute_data_length_after_meta( ctx, msg, msg_type); + if ( (msg_length + length_to_read) > (int)ctx->backend->max_adu_length ) + { + errno = EMBBADDATA; + _error_print(ctx, "too many data"); + return -1; + } + step = _STEP_DATA; + break; + default: + break; + } + } + + if (length_to_read > 0 && + (ctx->byte_timeout.tv_sec > 0 || ctx->byte_timeout.tv_usec > 0)) { + /* If there is no character in the buffer, the allowed timeout + interval between two consecutive bytes is defined by + byte_timeout */ + tv.tv_sec = ctx->byte_timeout.tv_sec; + tv.tv_usec = ctx->byte_timeout.tv_usec; + p_tv = &tv; + } + /* else timeout isn't set again, the full response must be read before + expiration of response timeout (for CONFIRMATION only) */ + } + + if (ctx->debug) + printf("\n"); + + return ctx->backend->check_integrity(ctx, msg, msg_length); +} + +/* Receive the request from a modbus master */ +int modbus_receive(modbus_t *ctx, uint8_t *req) +{ + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + return ctx->backend->receive(ctx, req); +} + +/* Receives the confirmation. + + The function shall store the read response in rsp and return the number of + values (bits or words). Otherwise, its shall return -1 and errno is set. + + The function doesn't check the confirmation is the expected response to the + initial request. +*/ +int modbus_receive_confirmation(modbus_t *ctx, uint8_t *rsp) +{ + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + return _modbus_receive_msg(ctx, rsp, MSG_CONFIRMATION); +} + +static int check_confirmation(modbus_t *ctx, uint8_t *req, + uint8_t *rsp, int rsp_length) +{ + int rc; + int rsp_length_computed; + const int offset = ctx->backend->header_length; + const int function = rsp[offset]; + + if (ctx->backend->pre_check_confirmation) { + rc = ctx->backend->pre_check_confirmation(ctx, req, rsp, rsp_length); + if (rc == -1) { + if (ctx->error_recovery & MODBUS_ERROR_RECOVERY_PROTOCOL) { + _sleep_response_timeout(ctx); + modbus_flush(ctx); + } + return -1; + } + } + + rsp_length_computed = compute_response_length_from_request(ctx, req); + + /* Exception code */ + if (function >= 0x80) { + if (rsp_length == (offset + 2 + (int)ctx->backend->checksum_length) && + req[offset] == (rsp[offset] - 0x80)) { + /* Valid exception code received */ + + int exception_code = rsp[offset + 1]; + if (exception_code < MODBUS_EXCEPTION_MAX) { + errno = MODBUS_ENOBASE + exception_code; + } else { + errno = EMBBADEXC; + } + _error_print(ctx, NULL); + return -1; + } else { + errno = EMBBADEXC; + _error_print(ctx, NULL); + return -1; + } + } + + /* Check length */ + if ((rsp_length == rsp_length_computed || + rsp_length_computed == MSG_LENGTH_UNDEFINED) && + function < 0x80) { + int req_nb_value; + int rsp_nb_value; + + /* Check function code */ + if (function != req[offset]) { + if (ctx->debug) { + fprintf(stderr, + "Received function not corresponding to the request (0x%X != 0x%X)\n", + function, req[offset]); + } + if (ctx->error_recovery & MODBUS_ERROR_RECOVERY_PROTOCOL) { + _sleep_response_timeout(ctx); + modbus_flush(ctx); + } + errno = EMBBADDATA; + return -1; + } + + /* Check the number of values is corresponding to the request */ + switch (function) { + case MODBUS_FC_READ_COILS: + case MODBUS_FC_READ_DISCRETE_INPUTS: + /* Read functions, 8 values in a byte (nb + * of values in the request and byte count in + * the response. */ + req_nb_value = (req[offset + 3] << 8) + req[offset + 4]; + req_nb_value = (req_nb_value / 8) + ((req_nb_value % 8) ? 1 : 0); + rsp_nb_value = rsp[offset + 1]; + break; + case MODBUS_FC_WRITE_AND_READ_REGISTERS: + case MODBUS_FC_READ_HOLDING_REGISTERS: + case MODBUS_FC_READ_INPUT_REGISTERS: + /* Read functions 1 value = 2 bytes */ + req_nb_value = (req[offset + 3] << 8) + req[offset + 4]; + rsp_nb_value = (rsp[offset + 1] / 2); + break; + case MODBUS_FC_WRITE_MULTIPLE_COILS: + case MODBUS_FC_WRITE_MULTIPLE_REGISTERS: + /* N Write functions */ + req_nb_value = (req[offset + 3] << 8) + req[offset + 4]; + rsp_nb_value = (rsp[offset + 3] << 8) | rsp[offset + 4]; + break; + case MODBUS_FC_REPORT_SLAVE_ID: + /* Report slave ID (bytes received) */ + req_nb_value = rsp_nb_value = rsp[offset + 1]; + break; + default: + /* 1 Write functions & others */ + req_nb_value = rsp_nb_value = 1; + } + + if (req_nb_value == rsp_nb_value) { + rc = rsp_nb_value; + } else { + if (ctx->debug) { + fprintf(stderr, + "Quantity not corresponding to the request (%d != %d)\n", + rsp_nb_value, req_nb_value); + } + + if (ctx->error_recovery & MODBUS_ERROR_RECOVERY_PROTOCOL) { + _sleep_response_timeout(ctx); + modbus_flush(ctx); + } + + errno = EMBBADDATA; + rc = -1; + } + } else { + if (ctx->debug) { + fprintf(stderr, + "Message length not corresponding to the computed length (%d != %d)\n", + rsp_length, rsp_length_computed); + } + if (ctx->error_recovery & MODBUS_ERROR_RECOVERY_PROTOCOL) { + _sleep_response_timeout(ctx); + modbus_flush(ctx); + } + errno = EMBBADDATA; + rc = -1; + } + + return rc; +} + +static int response_io_status(uint8_t *tab_io_status, + int address, int nb, + uint8_t *rsp, int offset) +{ + int shift = 0; + /* Instead of byte (not allowed in Win32) */ + int one_byte = 0; + int i; + + for (i = address; i < address + nb; i++) { + one_byte |= tab_io_status[i] << shift; + if (shift == 7) { + /* Byte is full */ + rsp[offset++] = one_byte; + one_byte = shift = 0; + } else { + shift++; + } + } + + if (shift != 0) + rsp[offset++] = one_byte; + + return offset; +} + +/* Build the exception response */ +static int response_exception(modbus_t *ctx, sft_t *sft, + int exception_code, uint8_t *rsp, + unsigned int to_flush, + const char* template, ...) +{ + int rsp_length; + + /* Print debug message */ + if (ctx->debug) { + va_list ap; + + va_start(ap, template); + vfprintf(stderr, template, ap); + va_end(ap); + } + + /* Flush if required */ + if (to_flush) { + _sleep_response_timeout(ctx); + modbus_flush(ctx); + } + + /* Build exception response */ + sft->function = sft->function + 0x80; + rsp_length = ctx->backend->build_response_basis(sft, rsp); + rsp[rsp_length++] = exception_code; + + return rsp_length; +} + +/* Send a response to the received request. + Analyses the request and constructs a response. + + If an error occurs, this function construct the response + accordingly. +*/ +int modbus_reply(modbus_t *ctx, const uint8_t *req, + int req_length, modbus_mapping_t *mb_mapping) +{ + int offset; + int slave; + int function; + uint16_t address; + uint8_t rsp[MAX_MESSAGE_LENGTH]; + int rsp_length = 0; + sft_t sft; + + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + offset = ctx->backend->header_length; + slave = req[offset - 1]; + function = req[offset]; + address = (req[offset + 1] << 8) + req[offset + 2]; + + sft.slave = slave; + sft.function = function; + sft.t_id = ctx->backend->prepare_response_tid(req, &req_length); + + /* Data are flushed on illegal number of values errors. */ + switch (function) { + case MODBUS_FC_READ_COILS: + case MODBUS_FC_READ_DISCRETE_INPUTS: { + unsigned int is_input = (function == MODBUS_FC_READ_DISCRETE_INPUTS); + int start_bits = is_input ? mb_mapping->start_input_bits : mb_mapping->start_bits; + int nb_bits = is_input ? mb_mapping->nb_input_bits : mb_mapping->nb_bits; + uint8_t *tab_bits = is_input ? mb_mapping->tab_input_bits : mb_mapping->tab_bits; + const char * const name = is_input ? "read_input_bits" : "read_bits"; + int nb = (req[offset + 3] << 8) + req[offset + 4]; + /* The mapping can be shifted to reduce memory consumption and it + doesn't always start at address zero. */ + int mapping_address = address - start_bits; + + if (nb < 1 || MODBUS_MAX_READ_BITS < nb) { + rsp_length = response_exception( + ctx, &sft, MODBUS_EXCEPTION_ILLEGAL_DATA_VALUE, rsp, TRUE, + "Illegal nb of values %d in %s (max %d)\n", + nb, name, MODBUS_MAX_READ_BITS); + } else if (mapping_address < 0 || (mapping_address + nb) > nb_bits) { + rsp_length = response_exception( + ctx, &sft, + MODBUS_EXCEPTION_ILLEGAL_DATA_ADDRESS, rsp, FALSE, + "Illegal data address 0x%0X in %s\n", + mapping_address < 0 ? address : address + nb, name); + } else { + rsp_length = ctx->backend->build_response_basis(&sft, rsp); + rsp[rsp_length++] = (nb / 8) + ((nb % 8) ? 1 : 0); + rsp_length = response_io_status(tab_bits, mapping_address, nb, + rsp, rsp_length); + } + } + break; + case MODBUS_FC_READ_HOLDING_REGISTERS: + case MODBUS_FC_READ_INPUT_REGISTERS: { + unsigned int is_input = (function == MODBUS_FC_READ_INPUT_REGISTERS); + int start_registers = is_input ? mb_mapping->start_input_registers : mb_mapping->start_registers; + int nb_registers = is_input ? mb_mapping->nb_input_registers : mb_mapping->nb_registers; + uint16_t *tab_registers = is_input ? mb_mapping->tab_input_registers : mb_mapping->tab_registers; + const char * const name = is_input ? "read_input_registers" : "read_registers"; + int nb = (req[offset + 3] << 8) + req[offset + 4]; + /* The mapping can be shifted to reduce memory consumption and it + doesn't always start at address zero. */ + int mapping_address = address - start_registers; + + if (nb < 1 || MODBUS_MAX_READ_REGISTERS < nb) { + rsp_length = response_exception( + ctx, &sft, MODBUS_EXCEPTION_ILLEGAL_DATA_VALUE, rsp, TRUE, + "Illegal nb of values %d in %s (max %d)\n", + nb, name, MODBUS_MAX_READ_REGISTERS); + } else if (mapping_address < 0 || (mapping_address + nb) > nb_registers) { + rsp_length = response_exception( + ctx, &sft, MODBUS_EXCEPTION_ILLEGAL_DATA_ADDRESS, rsp, FALSE, + "Illegal data address 0x%0X in %s\n", + mapping_address < 0 ? address : address + nb, name); + } else { + int i; + + rsp_length = ctx->backend->build_response_basis(&sft, rsp); + rsp[rsp_length++] = nb << 1; + for (i = mapping_address; i < mapping_address + nb; i++) { + rsp[rsp_length++] = tab_registers[i] >> 8; + rsp[rsp_length++] = tab_registers[i] & 0xFF; + } + } + } + break; + case MODBUS_FC_WRITE_SINGLE_COIL: { + int mapping_address = address - mb_mapping->start_bits; + + if (mapping_address < 0 || mapping_address >= mb_mapping->nb_bits) { + rsp_length = response_exception( + ctx, &sft, MODBUS_EXCEPTION_ILLEGAL_DATA_ADDRESS, rsp, FALSE, + "Illegal data address 0x%0X in write_bit\n", + address); + } else { + int data = (req[offset + 3] << 8) + req[offset + 4]; + + if (data == 0xFF00 || data == 0x0) { + mb_mapping->tab_bits[mapping_address] = data ? ON : OFF; + memcpy(rsp, req, req_length); + rsp_length = req_length; + } else { + rsp_length = response_exception( + ctx, &sft, + MODBUS_EXCEPTION_ILLEGAL_DATA_VALUE, rsp, FALSE, + "Illegal data value 0x%0X in write_bit request at address %0X\n", + data, address); + } + } + } + break; + case MODBUS_FC_WRITE_SINGLE_REGISTER: { + int mapping_address = address - mb_mapping->start_registers; + + if (mapping_address < 0 || mapping_address >= mb_mapping->nb_registers) { + rsp_length = response_exception( + ctx, &sft, + MODBUS_EXCEPTION_ILLEGAL_DATA_ADDRESS, rsp, FALSE, + "Illegal data address 0x%0X in write_register\n", + address); + } else { + int data = (req[offset + 3] << 8) + req[offset + 4]; + + mb_mapping->tab_registers[mapping_address] = data; + memcpy(rsp, req, req_length); + rsp_length = req_length; + } + } + break; + case MODBUS_FC_WRITE_MULTIPLE_COILS: { + int nb = (req[offset + 3] << 8) + req[offset + 4]; + int mapping_address = address - mb_mapping->start_bits; + + if (nb < 1 || MODBUS_MAX_WRITE_BITS < nb) { + /* May be the indication has been truncated on reading because of + * invalid address (eg. nb is 0 but the request contains values to + * write) so it's necessary to flush. */ + rsp_length = response_exception( + ctx, &sft, MODBUS_EXCEPTION_ILLEGAL_DATA_VALUE, rsp, TRUE, + "Illegal number of values %d in write_bits (max %d)\n", + nb, MODBUS_MAX_WRITE_BITS); + } else if (mapping_address < 0 || + (mapping_address + nb) > mb_mapping->nb_bits) { + rsp_length = response_exception( + ctx, &sft, + MODBUS_EXCEPTION_ILLEGAL_DATA_ADDRESS, rsp, FALSE, + "Illegal data address 0x%0X in write_bits\n", + mapping_address < 0 ? address : address + nb); + } else { + /* 6 = byte count */ + modbus_set_bits_from_bytes(mb_mapping->tab_bits, mapping_address, nb, + &req[offset + 6]); + + rsp_length = ctx->backend->build_response_basis(&sft, rsp); + /* 4 to copy the bit address (2) and the quantity of bits */ + memcpy(rsp + rsp_length, req + rsp_length, 4); + rsp_length += 4; + } + } + break; + case MODBUS_FC_WRITE_MULTIPLE_REGISTERS: { + int nb = (req[offset + 3] << 8) + req[offset + 4]; + int mapping_address = address - mb_mapping->start_registers; + + if (nb < 1 || MODBUS_MAX_WRITE_REGISTERS < nb) { + rsp_length = response_exception( + ctx, &sft, MODBUS_EXCEPTION_ILLEGAL_DATA_VALUE, rsp, TRUE, + "Illegal number of values %d in write_registers (max %d)\n", + nb, MODBUS_MAX_WRITE_REGISTERS); + } else if (mapping_address < 0 || + (mapping_address + nb) > mb_mapping->nb_registers) { + rsp_length = response_exception( + ctx, &sft, MODBUS_EXCEPTION_ILLEGAL_DATA_ADDRESS, rsp, FALSE, + "Illegal data address 0x%0X in write_registers\n", + mapping_address < 0 ? address : address + nb); + } else { + int i, j; + for (i = mapping_address, j = 6; i < mapping_address + nb; i++, j += 2) { + /* 6 and 7 = first value */ + mb_mapping->tab_registers[i] = + (req[offset + j] << 8) + req[offset + j + 1]; + } + + rsp_length = ctx->backend->build_response_basis(&sft, rsp); + /* 4 to copy the address (2) and the no. of registers */ + memcpy(rsp + rsp_length, req + rsp_length, 4); + rsp_length += 4; + } + } + break; + case MODBUS_FC_REPORT_SLAVE_ID: + { + int str_len; + int byte_count_pos; + + rsp_length = ctx->backend->build_response_basis(&sft, rsp); + /* Skip byte count for now */ + byte_count_pos = rsp_length++; + rsp[rsp_length++] = _REPORT_SLAVE_ID; + /* Run indicator status to ON */ + rsp[rsp_length++] = 0xFF; + str_len = 3 + strlen(MODBUS_VERSION_STRING); + memcpy(rsp + rsp_length, "LMB" MODBUS_VERSION_STRING, str_len); + rsp_length += str_len; + rsp[byte_count_pos] = rsp_length - byte_count_pos - 1; + } + break; + case MODBUS_FC_READ_EXCEPTION_STATUS: + if (ctx->debug) { + fprintf(stderr, "FIXME Not implemented\n"); + } + errno = ENOPROTOOPT; + return -1; + break; + case MODBUS_FC_MASK_WRITE_REGISTER: { + int mapping_address = address - mb_mapping->start_registers; + + if (mapping_address < 0 || mapping_address >= mb_mapping->nb_registers) { + rsp_length = response_exception( + ctx, &sft, MODBUS_EXCEPTION_ILLEGAL_DATA_ADDRESS, rsp, FALSE, + "Illegal data address 0x%0X in write_register\n", + address); + } else { + uint16_t data = mb_mapping->tab_registers[mapping_address]; + uint16_t and = (req[offset + 3] << 8) + req[offset + 4]; + uint16_t or = (req[offset + 5] << 8) + req[offset + 6]; + + data = (data & and) | (or & (~and)); + mb_mapping->tab_registers[mapping_address] = data; + memcpy(rsp, req, req_length); + rsp_length = req_length; + } + } + break; + case MODBUS_FC_WRITE_AND_READ_REGISTERS: { + int nb = (req[offset + 3] << 8) + req[offset + 4]; + uint16_t address_write = (req[offset + 5] << 8) + req[offset + 6]; + int nb_write = (req[offset + 7] << 8) + req[offset + 8]; + int nb_write_bytes = req[offset + 9]; + int mapping_address = address - mb_mapping->start_registers; + int mapping_address_write = address_write - mb_mapping->start_registers; + + if (nb_write < 1 || MODBUS_MAX_WR_WRITE_REGISTERS < nb_write || + nb < 1 || MODBUS_MAX_WR_READ_REGISTERS < nb || + nb_write_bytes != nb_write * 2) { + rsp_length = response_exception( + ctx, &sft, MODBUS_EXCEPTION_ILLEGAL_DATA_VALUE, rsp, TRUE, + "Illegal nb of values (W%d, R%d) in write_and_read_registers (max W%d, R%d)\n", + nb_write, nb, MODBUS_MAX_WR_WRITE_REGISTERS, MODBUS_MAX_WR_READ_REGISTERS); + } else if (mapping_address < 0 || + (mapping_address + nb) > mb_mapping->nb_registers || + mapping_address < 0 || + (mapping_address_write + nb_write) > mb_mapping->nb_registers) { + rsp_length = response_exception( + ctx, &sft, MODBUS_EXCEPTION_ILLEGAL_DATA_ADDRESS, rsp, FALSE, + "Illegal data read address 0x%0X or write address 0x%0X write_and_read_registers\n", + mapping_address < 0 ? address : address + nb, + mapping_address_write < 0 ? address_write : address_write + nb_write); + } else { + int i, j; + rsp_length = ctx->backend->build_response_basis(&sft, rsp); + rsp[rsp_length++] = nb << 1; + + /* Write first. + 10 and 11 are the offset of the first values to write */ + for (i = mapping_address_write, j = 10; + i < mapping_address_write + nb_write; i++, j += 2) { + mb_mapping->tab_registers[i] = + (req[offset + j] << 8) + req[offset + j + 1]; + } + + /* and read the data for the response */ + for (i = mapping_address; i < mapping_address + nb; i++) { + rsp[rsp_length++] = mb_mapping->tab_registers[i] >> 8; + rsp[rsp_length++] = mb_mapping->tab_registers[i] & 0xFF; + } + } + } + break; + + default: + rsp_length = response_exception( + ctx, &sft, MODBUS_EXCEPTION_ILLEGAL_FUNCTION, rsp, TRUE, + "Unknown Modbus function code: 0x%0X\n", function); + break; + } + + /* Suppress any responses when the request was a broadcast */ + return (slave == MODBUS_BROADCAST_ADDRESS) ? 0 : send_msg(ctx, rsp, rsp_length); +} + +int modbus_reply_exception(modbus_t *ctx, const uint8_t *req, + unsigned int exception_code) +{ + int offset; + int slave; + int function; + uint8_t rsp[MAX_MESSAGE_LENGTH]; + int rsp_length; + int dummy_length = 99; + sft_t sft; + + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + offset = ctx->backend->header_length; + slave = req[offset - 1]; + function = req[offset]; + + sft.slave = slave; + sft.function = function + 0x80;; + sft.t_id = ctx->backend->prepare_response_tid(req, &dummy_length); + rsp_length = ctx->backend->build_response_basis(&sft, rsp); + + /* Positive exception code */ + if (exception_code < MODBUS_EXCEPTION_MAX) { + rsp[rsp_length++] = exception_code; + return send_msg(ctx, rsp, rsp_length); + } else { + errno = EINVAL; + return -1; + } +} + +/* Reads IO status */ +static int read_io_status(modbus_t *ctx, int function, + int addr, int nb, uint8_t *dest) +{ + int rc; + int req_length; + + uint8_t req[_MIN_REQ_LENGTH]; + uint8_t rsp[MAX_MESSAGE_LENGTH]; + + req_length = ctx->backend->build_request_basis(ctx, function, addr, nb, req); + + rc = send_msg(ctx, req, req_length); + if (rc > 0) { + int i, temp, bit; + int pos = 0; + int offset; + int offset_end; + + rc = _modbus_receive_msg(ctx, rsp, MSG_CONFIRMATION); + if (rc == -1) + return -1; + + rc = check_confirmation(ctx, req, rsp, rc); + if (rc == -1) + return -1; + + offset = ctx->backend->header_length + 2; + offset_end = offset + rc; + for (i = offset; i < offset_end; i++) { + /* Shift reg hi_byte to temp */ + temp = rsp[i]; + + for (bit = 0x01; (bit & 0xff) && (pos < nb);) { + dest[pos++] = (temp & bit) ? TRUE : FALSE; + bit = bit << 1; + } + + } + } + + return rc; +} + +/* Reads the boolean status of bits and sets the array elements + in the destination to TRUE or FALSE (single bits). */ +int modbus_read_bits(modbus_t *ctx, int addr, int nb, uint8_t *dest) +{ + int rc; + + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + if (nb > MODBUS_MAX_READ_BITS) { + if (ctx->debug) { + fprintf(stderr, + "ERROR Too many bits requested (%d > %d)\n", + nb, MODBUS_MAX_READ_BITS); + } + errno = EMBMDATA; + return -1; + } + + rc = read_io_status(ctx, MODBUS_FC_READ_COILS, addr, nb, dest); + + if (rc == -1) + return -1; + else + return nb; +} + + +/* Same as modbus_read_bits but reads the remote device input table */ +int modbus_read_input_bits(modbus_t *ctx, int addr, int nb, uint8_t *dest) +{ + int rc; + + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + if (nb > MODBUS_MAX_READ_BITS) { + if (ctx->debug) { + fprintf(stderr, + "ERROR Too many discrete inputs requested (%d > %d)\n", + nb, MODBUS_MAX_READ_BITS); + } + errno = EMBMDATA; + return -1; + } + + rc = read_io_status(ctx, MODBUS_FC_READ_DISCRETE_INPUTS, addr, nb, dest); + + if (rc == -1) + return -1; + else + return nb; +} + +/* Reads the data from a remove device and put that data into an array */ +static int read_registers(modbus_t *ctx, int function, int addr, int nb, uint16_t *dest) +{ + int rc; + int req_length; + uint8_t req[_MIN_REQ_LENGTH]; + uint8_t rsp[MAX_MESSAGE_LENGTH]; + + if (nb > MODBUS_MAX_READ_REGISTERS) + { + if (ctx->debug) + { + fprintf(stderr, + "ERROR Too many registers requested (%d > %d)\n", + nb, MODBUS_MAX_READ_REGISTERS); + } + errno = EMBMDATA; + return -1; + } + + req_length = ctx->backend->build_request_basis(ctx, function, addr, nb, req); + + rc = send_msg(ctx, req, req_length); + if (rc > 0) + { + int offset; + int i; + + rc = _modbus_receive_msg(ctx, rsp, MSG_CONFIRMATION); + if (rc == -1) + return -1; + + rc = check_confirmation(ctx, req, rsp, rc); + if (rc == -1) + return -1; + + offset = ctx->backend->header_length; + + for (i = 0; i < rc; i++) { + /* shift reg hi_byte to temp OR with lo_byte */ + dest[i] = (rsp[offset + 2 + (i << 1)] << 8) | + rsp[offset + 3 + (i << 1)]; + } + } + + return rc; +} + +/* Reads the holding registers of remote device and put the data into an + array */ +int modbus_read_registers(modbus_t *ctx, int addr, int nb, uint16_t *dest) +{ + int status; + + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + if (nb > MODBUS_MAX_READ_REGISTERS) + { + if (ctx->debug) + { + fprintf(stderr, + "ERROR Too many registers requested (%d > %d)\n", + nb, MODBUS_MAX_READ_REGISTERS); + } + errno = EMBMDATA; + return -1; + } + + status = read_registers(ctx, MODBUS_FC_READ_HOLDING_REGISTERS, + addr, nb, dest); + return status; +} + +/* Reads the input registers of remote device and put the data into an array */ +int modbus_read_input_registers(modbus_t *ctx, int addr, int nb, + uint16_t *dest) +{ + int status; + + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + if (nb > MODBUS_MAX_READ_REGISTERS) { + fprintf(stderr, + "ERROR Too many input registers requested (%d > %d)\n", + nb, MODBUS_MAX_READ_REGISTERS); + errno = EMBMDATA; + return -1; + } + + status = read_registers(ctx, MODBUS_FC_READ_INPUT_REGISTERS, + addr, nb, dest); + + return status; +} + +/* Write a value to the specified register of the remote device. + Used by write_bit and write_register */ +static int write_single(modbus_t *ctx, int function, int addr, int value) +{ + int rc; + int req_length; + uint8_t req[_MIN_REQ_LENGTH]; + + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + req_length = ctx->backend->build_request_basis(ctx, function, addr, value, req); + + rc = send_msg(ctx, req, req_length); + if (rc > 0) { + /* Used by write_bit and write_register */ + uint8_t rsp[MAX_MESSAGE_LENGTH]; + + rc = _modbus_receive_msg(ctx, rsp, MSG_CONFIRMATION); + if (rc == -1) + return -1; + + rc = check_confirmation(ctx, req, rsp, rc); + } + + return rc; +} + +/* Turns ON or OFF a single bit of the remote device */ +int modbus_write_bit(modbus_t *ctx, int addr, int status) +{ + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + return write_single(ctx, MODBUS_FC_WRITE_SINGLE_COIL, addr, + status ? 0xFF00 : 0); +} + +/* Writes a value in one register of the remote device */ +int modbus_write_register(modbus_t *ctx, int addr, int value) +{ + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + return write_single(ctx, MODBUS_FC_WRITE_SINGLE_REGISTER, addr, value); +} + +/* Write the bits of the array in the remote device */ +int modbus_write_bits(modbus_t *ctx, int addr, int nb, const uint8_t *src) +{ + int rc; + int i; + int byte_count; + int req_length; + int bit_check = 0; + int pos = 0; + uint8_t req[MAX_MESSAGE_LENGTH]; + + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + if (nb > MODBUS_MAX_WRITE_BITS) { + if (ctx->debug) { + fprintf(stderr, "ERROR Writing too many bits (%d > %d)\n", + nb, MODBUS_MAX_WRITE_BITS); + } + errno = EMBMDATA; + return -1; + } + + req_length = ctx->backend->build_request_basis(ctx, + MODBUS_FC_WRITE_MULTIPLE_COILS, + addr, nb, req); + byte_count = (nb / 8) + ((nb % 8) ? 1 : 0); + req[req_length++] = byte_count; + + for (i = 0; i < byte_count; i++) { + int bit; + + bit = 0x01; + req[req_length] = 0; + + while ((bit & 0xFF) && (bit_check++ < nb)) { + if (src[pos++]) + req[req_length] |= bit; + else + req[req_length] &=~ bit; + + bit = bit << 1; + } + req_length++; + } + + rc = send_msg(ctx, req, req_length); + if (rc > 0) { + uint8_t rsp[MAX_MESSAGE_LENGTH]; + + rc = _modbus_receive_msg(ctx, rsp, MSG_CONFIRMATION); + if (rc == -1) + return -1; + + rc = check_confirmation(ctx, req, rsp, rc); + } + + + return rc; +} + +/* Write the values from the array to the registers of the remote device */ +int modbus_write_registers(modbus_t *ctx, int addr, int nb, const uint16_t *src) +{ + int rc; + int i; + int req_length; + int byte_count; + uint8_t req[MAX_MESSAGE_LENGTH]; + + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + if (nb > MODBUS_MAX_WRITE_REGISTERS) { + if (ctx->debug) { + fprintf(stderr, + "ERROR Trying to write to too many registers (%d > %d)\n", + nb, MODBUS_MAX_WRITE_REGISTERS); + } + errno = EMBMDATA; + return -1; + } + + req_length = ctx->backend->build_request_basis(ctx, + MODBUS_FC_WRITE_MULTIPLE_REGISTERS, + addr, nb, req); + byte_count = nb * 2; + req[req_length++] = byte_count; + + for (i = 0; i < nb; i++) { + req[req_length++] = src[i] >> 8; + req[req_length++] = src[i] & 0x00FF; + } + + rc = send_msg(ctx, req, req_length); + if (rc > 0) { + uint8_t rsp[MAX_MESSAGE_LENGTH]; + + rc = _modbus_receive_msg(ctx, rsp, MSG_CONFIRMATION); + if (rc == -1) + return -1; + + rc = check_confirmation(ctx, req, rsp, rc); + } + + return rc; +} + +int modbus_mask_write_register(modbus_t *ctx, int addr, uint16_t and_mask, uint16_t or_mask) +{ + int rc; + int req_length; + /* The request length can not exceed _MIN_REQ_LENGTH - 2 and 4 bytes to + * store the masks. The ugly substraction is there to remove the 'nb' value + * (2 bytes) which is not used. */ + uint8_t req[_MIN_REQ_LENGTH + 2]; + + req_length = ctx->backend->build_request_basis(ctx, + MODBUS_FC_MASK_WRITE_REGISTER, + addr, 0, req); + + /* HACKISH, count is not used */ + req_length -= 2; + + req[req_length++] = and_mask >> 8; + req[req_length++] = and_mask & 0x00ff; + req[req_length++] = or_mask >> 8; + req[req_length++] = or_mask & 0x00ff; + + rc = send_msg(ctx, req, req_length); + if (rc > 0) { + /* Used by write_bit and write_register */ + uint8_t rsp[MAX_MESSAGE_LENGTH]; + + rc = _modbus_receive_msg(ctx, rsp, MSG_CONFIRMATION); + if (rc == -1) + return -1; + + rc = check_confirmation(ctx, req, rsp, rc); + } + + return rc; +} + +/* Write multiple registers from src array to remote device and read multiple + registers from remote device to dest array. */ +int modbus_write_and_read_registers(modbus_t *ctx, + int write_addr, int write_nb, + const uint16_t *src, + int read_addr, int read_nb, + uint16_t *dest) + +{ + int rc; + int req_length; + int i; + int byte_count; + uint8_t req[MAX_MESSAGE_LENGTH]; + uint8_t rsp[MAX_MESSAGE_LENGTH]; + + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + if (write_nb > MODBUS_MAX_WR_WRITE_REGISTERS) { + if (ctx->debug) { + fprintf(stderr, + "ERROR Too many registers to write (%d > %d)\n", + write_nb, MODBUS_MAX_WR_WRITE_REGISTERS); + } + errno = EMBMDATA; + return -1; + } + + if (read_nb > MODBUS_MAX_WR_READ_REGISTERS) { + if (ctx->debug) { + fprintf(stderr, + "ERROR Too many registers requested (%d > %d)\n", + read_nb, MODBUS_MAX_WR_READ_REGISTERS); + } + errno = EMBMDATA; + return -1; + } + req_length = ctx->backend->build_request_basis(ctx, + MODBUS_FC_WRITE_AND_READ_REGISTERS, + read_addr, read_nb, req); + + req[req_length++] = write_addr >> 8; + req[req_length++] = write_addr & 0x00ff; + req[req_length++] = write_nb >> 8; + req[req_length++] = write_nb & 0x00ff; + byte_count = write_nb * 2; + req[req_length++] = byte_count; + + for (i = 0; i < write_nb; i++) { + req[req_length++] = src[i] >> 8; + req[req_length++] = src[i] & 0x00FF; + } + + rc = send_msg(ctx, req, req_length); + if (rc > 0) { + int offset; + + rc = _modbus_receive_msg(ctx, rsp, MSG_CONFIRMATION); + if (rc == -1) + return -1; + + rc = check_confirmation(ctx, req, rsp, rc); + if (rc == -1) + return -1; + + offset = ctx->backend->header_length; + for (i = 0; i < rc; i++) { + /* shift reg hi_byte to temp OR with lo_byte */ + dest[i] = (rsp[offset + 2 + (i << 1)] << 8) | + rsp[offset + 3 + (i << 1)]; + } + } + + return rc; +} + +/* Send a request to get the slave ID of the device (only available in serial + communication). */ +int modbus_report_slave_id(modbus_t *ctx, int max_dest, uint8_t *dest) +{ + int rc; + int req_length; + uint8_t req[_MIN_REQ_LENGTH]; + + if (ctx == NULL || max_dest <= 0) { + errno = EINVAL; + return -1; + } + + req_length = ctx->backend->build_request_basis(ctx, MODBUS_FC_REPORT_SLAVE_ID, + 0, 0, req); + + /* HACKISH, addr and count are not used */ + req_length -= 4; + + rc = send_msg(ctx, req, req_length); + if (rc > 0) { + int i; + int offset; + uint8_t rsp[MAX_MESSAGE_LENGTH]; + + rc = _modbus_receive_msg(ctx, rsp, MSG_CONFIRMATION); + if (rc == -1) + return -1; + + rc = check_confirmation(ctx, req, rsp, rc); + if (rc == -1) + return -1; + + offset = ctx->backend->header_length + 2; + + /* Byte count, slave id, run indicator status and + additional data. Truncate copy to max_dest. */ + for (i=0; i < rc && i < max_dest; i++) { + dest[i] = rsp[offset + i]; + } + } + + return rc; +} + +void _modbus_init_common(modbus_t *ctx) +{ + /* Slave and socket are initialized to -1 */ + ctx->slave = -1; + ctx->s = -1; + + ctx->debug = FALSE; + ctx->error_recovery = MODBUS_ERROR_RECOVERY_NONE; + + ctx->response_timeout.tv_sec = 0; + ctx->response_timeout.tv_usec = _RESPONSE_TIMEOUT; + + ctx->byte_timeout.tv_sec = 0; + ctx->byte_timeout.tv_usec = _BYTE_TIMEOUT; +} + +/* Define the slave number */ +int modbus_set_slave(modbus_t *ctx, int slave) +{ + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + return ctx->backend->set_slave(ctx, slave); +} + +int modbus_set_error_recovery(modbus_t *ctx, + modbus_error_recovery_mode error_recovery) +{ + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + /* The type of modbus_error_recovery_mode is unsigned enum */ + ctx->error_recovery = (uint8_t) error_recovery; + return 0; +} + +int modbus_set_socket(modbus_t *ctx, int s) +{ + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + ctx->s = s; + return 0; +} + +int modbus_get_socket(modbus_t *ctx) +{ + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + return ctx->s; +} + +/* Get the timeout interval used to wait for a response */ +int modbus_get_response_timeout(modbus_t *ctx, uint32_t *to_sec, uint32_t *to_usec) +{ + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + *to_sec = ctx->response_timeout.tv_sec; + *to_usec = ctx->response_timeout.tv_usec; + return 0; +} + +int modbus_set_response_timeout(modbus_t *ctx, uint32_t to_sec, uint32_t to_usec) +{ + if (ctx == NULL || + (to_sec == 0 && to_usec == 0) || to_usec > 999999) { + errno = EINVAL; + return -1; + } + + ctx->response_timeout.tv_sec = to_sec; + ctx->response_timeout.tv_usec = to_usec; + return 0; +} + +/* Get the timeout interval between two consecutive bytes of a message */ +int modbus_get_byte_timeout(modbus_t *ctx, uint32_t *to_sec, uint32_t *to_usec) +{ + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + *to_sec = ctx->byte_timeout.tv_sec; + *to_usec = ctx->byte_timeout.tv_usec; + return 0; +} + +int modbus_set_byte_timeout(modbus_t *ctx, uint32_t to_sec, uint32_t to_usec) +{ + /* Byte timeout can be disabled when both values are zero */ + if (ctx == NULL || to_usec > 999999) { + errno = EINVAL; + return -1; + } + + ctx->byte_timeout.tv_sec = to_sec; + ctx->byte_timeout.tv_usec = to_usec; + return 0; +} + +int modbus_get_header_length(modbus_t *ctx) +{ + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + return ctx->backend->header_length; +} + +int modbus_connect(modbus_t *ctx) +{ + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + return ctx->backend->connect(ctx); +} + +void modbus_close(modbus_t *ctx) +{ + if (ctx == NULL) + return; + + ctx->backend->close(ctx); +} + +void modbus_free(modbus_t *ctx) +{ + if (ctx == NULL) + return; + + ctx->backend->free(ctx); +} + +int modbus_set_debug(modbus_t *ctx, int flag) +{ + if (ctx == NULL) { + errno = EINVAL; + return -1; + } + + ctx->debug = flag; + return 0; +} + +/* Allocates 4 arrays to store bits, input bits, registers and inputs + registers. The pointers are stored in modbus_mapping structure. + + The modbus_mapping_new_ranges() function shall return the new allocated + structure if successful. Otherwise it shall return NULL and set errno to + ENOMEM. */ +modbus_mapping_t* modbus_mapping_new_start_address( + unsigned int start_bits, unsigned int nb_bits, + unsigned int start_input_bits, unsigned int nb_input_bits, + unsigned int start_registers, unsigned int nb_registers, + unsigned int start_input_registers, unsigned int nb_input_registers) +{ + modbus_mapping_t *mb_mapping; + + mb_mapping = (modbus_mapping_t *)malloc(sizeof(modbus_mapping_t)); + if (mb_mapping == NULL) { + return NULL; + } + + /* 0X */ + mb_mapping->nb_bits = nb_bits; + mb_mapping->start_bits = start_bits; + if (nb_bits == 0) { + mb_mapping->tab_bits = NULL; + } else { + /* Negative number raises a POSIX error */ + mb_mapping->tab_bits = + (uint8_t *) malloc(nb_bits * sizeof(uint8_t)); + if (mb_mapping->tab_bits == NULL) { + free(mb_mapping); + return NULL; + } + memset(mb_mapping->tab_bits, 0, nb_bits * sizeof(uint8_t)); + } + + /* 1X */ + mb_mapping->nb_input_bits = nb_input_bits; + mb_mapping->start_input_bits = start_input_bits; + if (nb_input_bits == 0) { + mb_mapping->tab_input_bits = NULL; + } else { + mb_mapping->tab_input_bits = + (uint8_t *) malloc(nb_input_bits * sizeof(uint8_t)); + if (mb_mapping->tab_input_bits == NULL) { + free(mb_mapping->tab_bits); + free(mb_mapping); + return NULL; + } + memset(mb_mapping->tab_input_bits, 0, nb_input_bits * sizeof(uint8_t)); + } + + /* 4X */ + mb_mapping->nb_registers = nb_registers; + mb_mapping->start_registers = start_registers; + if (nb_registers == 0) { + mb_mapping->tab_registers = NULL; + } else { + mb_mapping->tab_registers = + (uint16_t *) malloc(nb_registers * sizeof(uint16_t)); + if (mb_mapping->tab_registers == NULL) { + free(mb_mapping->tab_input_bits); + free(mb_mapping->tab_bits); + free(mb_mapping); + return NULL; + } + memset(mb_mapping->tab_registers, 0, nb_registers * sizeof(uint16_t)); + } + + /* 3X */ + mb_mapping->nb_input_registers = nb_input_registers; + mb_mapping->start_input_registers = start_input_registers; + if (nb_input_registers == 0) { + mb_mapping->tab_input_registers = NULL; + } else { + mb_mapping->tab_input_registers = + (uint16_t *) malloc(nb_input_registers * sizeof(uint16_t)); + if (mb_mapping->tab_input_registers == NULL) { + free(mb_mapping->tab_registers); + free(mb_mapping->tab_input_bits); + free(mb_mapping->tab_bits); + free(mb_mapping); + return NULL; + } + memset(mb_mapping->tab_input_registers, 0, + nb_input_registers * sizeof(uint16_t)); + } + + return mb_mapping; +} + +modbus_mapping_t* modbus_mapping_new(int nb_bits, int nb_input_bits, + int nb_registers, int nb_input_registers) +{ + return modbus_mapping_new_start_address( + 0, nb_bits, 0, nb_input_bits, 0, nb_registers, 0, nb_input_registers); +} + +/* Frees the 4 arrays */ +void modbus_mapping_free(modbus_mapping_t *mb_mapping) +{ + if (mb_mapping == NULL) { + return; + } + + free(mb_mapping->tab_input_registers); + free(mb_mapping->tab_registers); + free(mb_mapping->tab_input_bits); + free(mb_mapping->tab_bits); + free(mb_mapping); +} + +#ifndef HAVE_STRLCPY +/* + * Function strlcpy was originally developed by + * Todd C. Miller to simplify writing secure code. + * See ftp://ftp.openbsd.org/pub/OpenBSD/src/lib/libc/string/strlcpy.3 + * for more information. + * + * Thank you Ulrich Drepper... not! + * + * Copy src to string dest of size dest_size. At most dest_size-1 characters + * will be copied. Always NUL terminates (unless dest_size == 0). Returns + * strlen(src); if retval >= dest_size, truncation occurred. + */ +size_t strlcpy(char *dest, const char *src, size_t dest_size) +{ + register char *d = dest; + register const char *s = src; + register size_t n = dest_size; + + /* Copy as many bytes as will fit */ + if (n != 0 && --n != 0) { + do { + if ((*d++ = *s++) == 0) + break; + } while (--n != 0); + } + + /* Not enough room in dest, add NUL and traverse rest of src */ + if (n == 0) { + if (dest_size != 0) + *d = '\0'; /* NUL-terminate dest */ + while (*s++) + ; + } + + return (s - src - 1); /* count does not include NUL */ +} +#endif diff --git a/stack/modbus.h b/stack/modbus.h new file mode 100644 index 0000000..8e15a95 --- /dev/null +++ b/stack/modbus.h @@ -0,0 +1,262 @@ + +#pragma once + +/* Add this for macros that defined unix flavor */ +#if (defined(__unix__) || defined(unix)) && !defined(USG) +#include +#endif + +#include + +#define MODBUS_API + +#define MODBUS_VERSION_STRING "1.0.0" + +#ifdef __cplusplus +#define MODBUS_BEGIN_DECLS extern "C" { +#define MODBUS_END_DECLS } +#else +# define MODBUS_BEGIN_DECLS +# define MODBUS_END_DECLS +#endif + +MODBUS_BEGIN_DECLS + +#ifndef FALSE +#define FALSE 0 +#endif + +#ifndef TRUE +#define TRUE 1 +#endif + +#ifndef OFF +#define OFF 0 +#endif + +#ifndef ON +#define ON 1 +#endif + +/* Modbus function codes */ +#define MODBUS_FC_READ_COILS 0x01 +#define MODBUS_FC_READ_DISCRETE_INPUTS 0x02 +#define MODBUS_FC_READ_HOLDING_REGISTERS 0x03 +#define MODBUS_FC_READ_INPUT_REGISTERS 0x04 +#define MODBUS_FC_WRITE_SINGLE_COIL 0x05 +#define MODBUS_FC_WRITE_SINGLE_REGISTER 0x06 +#define MODBUS_FC_READ_EXCEPTION_STATUS 0x07 +#define MODBUS_FC_WRITE_MULTIPLE_COILS 0x0F +#define MODBUS_FC_WRITE_MULTIPLE_REGISTERS 0x10 +#define MODBUS_FC_REPORT_SLAVE_ID 0x11 +#define MODBUS_FC_MASK_WRITE_REGISTER 0x16 +#define MODBUS_FC_WRITE_AND_READ_REGISTERS 0x17 + +#define MODBUS_BROADCAST_ADDRESS 0 + +/* Modbus_Application_Protocol_V1_1b.pdf (chapter 6 section 1 page 12) + * Quantity of Coils to read (2 bytes): 1 to 2000 (0x7D0) + * (chapter 6 section 11 page 29) + * Quantity of Coils to write (2 bytes): 1 to 1968 (0x7B0) + */ +#define MODBUS_MAX_READ_BITS 2000 +#define MODBUS_MAX_WRITE_BITS 1968 + +/* Modbus_Application_Protocol_V1_1b.pdf (chapter 6 section 3 page 15) + * Quantity of Registers to read (2 bytes): 1 to 125 (0x7D) + * (chapter 6 section 12 page 31) + * Quantity of Registers to write (2 bytes) 1 to 123 (0x7B) + * (chapter 6 section 17 page 38) + * Quantity of Registers to write in R/W registers (2 bytes) 1 to 121 (0x79) + */ +#define MODBUS_MAX_READ_REGISTERS 125 +#define MODBUS_MAX_WRITE_REGISTERS 123 +#define MODBUS_MAX_WR_WRITE_REGISTERS 121 +#define MODBUS_MAX_WR_READ_REGISTERS 125 + +/* The size of the MODBUS PDU is limited by the size constraint inherited from + * the first MODBUS implementation on Serial Line network (max. RS485 ADU = 256 + * bytes). Therefore, MODBUS PDU for serial line communication = 256 - Server + * address (1 byte) - CRC (2 bytes) = 253 bytes. + */ +#define MODBUS_MAX_PDU_LENGTH 253 + +/* Consequently: + * - RTU MODBUS ADU = 253 bytes + Server address (1 byte) + CRC (2 bytes) = 256 + * bytes. + * - TCP MODBUS ADU = 253 bytes + MBAP (7 bytes) = 260 bytes. + * so the maximum of both backend in 260 bytes. This size can used to allocate + * an array of bytes to store responses and it will be compatible with the two + * backends. + */ +#define MODBUS_MAX_ADU_LENGTH 260 + +/* Random number to avoid errno conflicts */ +#define MODBUS_ENOBASE 112345678 + +/* Protocol exceptions */ +enum { + MODBUS_EXCEPTION_ILLEGAL_FUNCTION = 0x01, + MODBUS_EXCEPTION_ILLEGAL_DATA_ADDRESS, + MODBUS_EXCEPTION_ILLEGAL_DATA_VALUE, + MODBUS_EXCEPTION_SLAVE_OR_SERVER_FAILURE, + MODBUS_EXCEPTION_ACKNOWLEDGE, + MODBUS_EXCEPTION_SLAVE_OR_SERVER_BUSY, + MODBUS_EXCEPTION_NEGATIVE_ACKNOWLEDGE, + MODBUS_EXCEPTION_MEMORY_PARITY, + MODBUS_EXCEPTION_NOT_DEFINED, + MODBUS_EXCEPTION_GATEWAY_PATH, + MODBUS_EXCEPTION_GATEWAY_TARGET, + MODBUS_EXCEPTION_MAX +}; + +#define EMBXILFUN (MODBUS_ENOBASE + MODBUS_EXCEPTION_ILLEGAL_FUNCTION) +#define EMBXILADD (MODBUS_ENOBASE + MODBUS_EXCEPTION_ILLEGAL_DATA_ADDRESS) +#define EMBXILVAL (MODBUS_ENOBASE + MODBUS_EXCEPTION_ILLEGAL_DATA_VALUE) +#define EMBXSFAIL (MODBUS_ENOBASE + MODBUS_EXCEPTION_SLAVE_OR_SERVER_FAILURE) +#define EMBXACK (MODBUS_ENOBASE + MODBUS_EXCEPTION_ACKNOWLEDGE) +#define EMBXSBUSY (MODBUS_ENOBASE + MODBUS_EXCEPTION_SLAVE_OR_SERVER_BUSY) +#define EMBXNACK (MODBUS_ENOBASE + MODBUS_EXCEPTION_NEGATIVE_ACKNOWLEDGE) +#define EMBXMEMPAR (MODBUS_ENOBASE + MODBUS_EXCEPTION_MEMORY_PARITY) +#define EMBXGPATH (MODBUS_ENOBASE + MODBUS_EXCEPTION_GATEWAY_PATH) +#define EMBXGTAR (MODBUS_ENOBASE + MODBUS_EXCEPTION_GATEWAY_TARGET) + +/* Native libmodbus error codes */ +#define EMBBADCRC (EMBXGTAR + 1) +#define EMBBADDATA (EMBXGTAR + 2) +#define EMBBADEXC (EMBXGTAR + 3) +#define EMBUNKEXC (EMBXGTAR + 4) +#define EMBMDATA (EMBXGTAR + 5) +#define EMBBADSLAVE (EMBXGTAR + 6) + +typedef struct _modbus modbus_t; + +typedef struct { + int nb_bits; + int start_bits; + int nb_input_bits; + int start_input_bits; + int nb_input_registers; + int start_input_registers; + int nb_registers; + int start_registers; + uint8_t *tab_bits; + uint8_t *tab_input_bits; + uint16_t *tab_input_registers; + uint16_t *tab_registers; +} modbus_mapping_t; + +typedef enum +{ + MODBUS_ERROR_RECOVERY_NONE = 0, + MODBUS_ERROR_RECOVERY_LINK = (1<<1), + MODBUS_ERROR_RECOVERY_PROTOCOL = (1<<2) +} modbus_error_recovery_mode; + +MODBUS_API int modbus_set_slave(modbus_t* ctx, int slave); +MODBUS_API int modbus_set_error_recovery(modbus_t *ctx, modbus_error_recovery_mode error_recovery); +MODBUS_API int modbus_set_socket(modbus_t *ctx, int s); +MODBUS_API int modbus_get_socket(modbus_t *ctx); + +MODBUS_API int modbus_get_response_timeout(modbus_t *ctx, uint32_t *to_sec, uint32_t *to_usec); +MODBUS_API int modbus_set_response_timeout(modbus_t *ctx, uint32_t to_sec, uint32_t to_usec); + +MODBUS_API int modbus_get_byte_timeout(modbus_t *ctx, uint32_t *to_sec, uint32_t *to_usec); +MODBUS_API int modbus_set_byte_timeout(modbus_t *ctx, uint32_t to_sec, uint32_t to_usec); + +MODBUS_API int modbus_get_header_length(modbus_t *ctx); + +MODBUS_API int modbus_connect(modbus_t *ctx); +MODBUS_API void modbus_close(modbus_t *ctx); + +MODBUS_API void modbus_free(modbus_t *ctx); + +MODBUS_API int modbus_flush(modbus_t *ctx); +MODBUS_API int modbus_set_debug(modbus_t *ctx, int flag); + +MODBUS_API const char *modbus_strerror(int errnum); + +MODBUS_API int modbus_read_bits(modbus_t *ctx, int addr, int nb, uint8_t *dest); +MODBUS_API int modbus_read_input_bits(modbus_t *ctx, int addr, int nb, uint8_t *dest); +MODBUS_API int modbus_read_registers(modbus_t *ctx, int addr, int nb, uint16_t *dest); +MODBUS_API int modbus_read_input_registers(modbus_t *ctx, int addr, int nb, uint16_t *dest); +MODBUS_API int modbus_write_bit(modbus_t *ctx, int coil_addr, int status); +MODBUS_API int modbus_write_register(modbus_t *ctx, int reg_addr, int value); +MODBUS_API int modbus_write_bits(modbus_t *ctx, int addr, int nb, const uint8_t *data); +MODBUS_API int modbus_write_registers(modbus_t *ctx, int addr, int nb, const uint16_t *data); +MODBUS_API int modbus_mask_write_register(modbus_t *ctx, int addr, uint16_t and_mask, uint16_t or_mask); +MODBUS_API int modbus_write_and_read_registers(modbus_t *ctx, int write_addr, int write_nb,const uint16_t *src, int read_addr, int read_nb,uint16_t *dest); +MODBUS_API int modbus_report_slave_id(modbus_t *ctx, int max_dest, uint8_t *dest); + +MODBUS_API modbus_mapping_t* modbus_mapping_new_start_address +( + unsigned int start_bits, unsigned int nb_bits, + unsigned int start_input_bits, unsigned int nb_input_bits, + unsigned int start_registers, unsigned int nb_registers, + unsigned int start_input_registers, unsigned int nb_input_registers +); + +MODBUS_API modbus_mapping_t* modbus_mapping_new(int nb_bits, int nb_input_bits, int nb_registers, int nb_input_registers); +MODBUS_API void modbus_mapping_free(modbus_mapping_t *mb_mapping); + +MODBUS_API int modbus_send_raw_request(modbus_t *ctx, uint8_t *raw_req, int raw_req_length); + +MODBUS_API int modbus_receive(modbus_t *ctx, uint8_t *req); + +MODBUS_API int modbus_receive_confirmation(modbus_t *ctx, uint8_t *rsp); + +MODBUS_API int modbus_reply(modbus_t *ctx, const uint8_t *req, int req_length, modbus_mapping_t *mb_mapping); +MODBUS_API int modbus_reply_exception(modbus_t *ctx, const uint8_t *req, unsigned int exception_code); + +/** + * UTILS FUNCTIONS + **/ + +#define MODBUS_GET_HIGH_BYTE(data) (((data) >> 8) & 0xFF) +#define MODBUS_GET_LOW_BYTE(data) ((data) & 0xFF) +#define MODBUS_GET_INT64_FROM_INT16(tab_int16, index) \ + (((int64_t)tab_int16[(index) ] << 48) + \ + ((int64_t)tab_int16[(index) + 1] << 32) + \ + ((int64_t)tab_int16[(index) + 2] << 16) + \ + (int64_t)tab_int16[(index) + 3]) +#define MODBUS_GET_INT32_FROM_INT16(tab_int16, index) ((tab_int16[(index)] << 16) + tab_int16[(index) + 1]) +#define MODBUS_GET_INT16_FROM_INT8(tab_int8, index) ((tab_int8[(index)] << 8) + tab_int8[(index) + 1]) +#define MODBUS_SET_INT16_TO_INT8(tab_int8, index, value) \ + do { \ + tab_int8[(index)] = (value) >> 8; \ + tab_int8[(index) + 1] = (value) & 0xFF; \ + } while (0) +#define MODBUS_SET_INT32_TO_INT16(tab_int16, index, value) \ + do { \ + tab_int16[(index) ] = (value) >> 16; \ + tab_int16[(index) + 1] = (value); \ + } while (0) +#define MODBUS_SET_INT64_TO_INT16(tab_int16, index, value) \ + do { \ + tab_int16[(index) ] = (value) >> 48; \ + tab_int16[(index) + 1] = (value) >> 32; \ + tab_int16[(index) + 2] = (value) >> 16; \ + tab_int16[(index) + 3] = (value); \ + } while (0) + +MODBUS_API void modbus_set_bits_from_byte(uint8_t *dest, int idx, const uint8_t value); +MODBUS_API void modbus_set_bits_from_bytes(uint8_t *dest, int idx, unsigned int nb_bits, + const uint8_t *tab_byte); +MODBUS_API uint8_t modbus_get_byte_from_bits(const uint8_t *src, int idx, unsigned int nb_bits); +MODBUS_API float modbus_get_float(const uint16_t *src); +MODBUS_API float modbus_get_float_abcd(const uint16_t *src); +MODBUS_API float modbus_get_float_dcba(const uint16_t *src); +MODBUS_API float modbus_get_float_badc(const uint16_t *src); +MODBUS_API float modbus_get_float_cdab(const uint16_t *src); + +MODBUS_API void modbus_set_float(float f, uint16_t *dest); +MODBUS_API void modbus_set_float_abcd(float f, uint16_t *dest); +MODBUS_API void modbus_set_float_dcba(float f, uint16_t *dest); +MODBUS_API void modbus_set_float_badc(float f, uint16_t *dest); +MODBUS_API void modbus_set_float_cdab(float f, uint16_t *dest); + +#include "modbus-tcp.h" +#include "modbus-rtu.h" + +MODBUS_END_DECLS + -- libgit2 0.21.4