Created C version

include/can_wrap.h

@@ -1,196 +1,136 @@
 #ifndef CAN_WRAP_H
 #define CAN_WRAP_H
 
-#include <net/if.h>
+#include <linux/if.h>
 #include <sys/ioctl.h>
 #include <sys/socket.h>
 #include <unistd.h>
 
 #include <linux/can.h>
 #include <linux/can/raw.h>
 
-#include <cstring>
-#include <iomanip>
-#include <iostream>
-#include <stdexcept>
+#include <stdbool.h>
+#include <string.h>
+
+/**
+ * @brief Opens socket for CAN bus communication via socketcan. 
+ * Returns socket identifier which is used as an argument for 
+ * future can::read(), can::write() and can::close() calls.
+ * 
+ * 
+ * @param fd Open as normal CAN or CANFD.
+ * @param channel Network channel to use, e.g. can0 or vcan0.
+ * @return const int Socket identifier.
+ * @return -1 If socket creation failed.
+ * @return -2 If could not enable CANFD.
+ * @return -3 If could not bind socket.
+ */
+const int can_connect( const char* channel, const bool fd  )
+{
+    const int canSocket = socket( PF_CAN, SOCK_RAW, CAN_RAW );
+    if( canSocket < 0 )
+        return -1;
+
+    struct ifreq ifr;
+    strncpy( ifr.ifr_name, channel, sizeof(ifr.ifr_name)-1 );
+    ioctl( canSocket, SIOCGIFINDEX, &ifr );
+
+    struct sockaddr_can addr;
+    memset( &addr, 0, sizeof(addr) );
+    addr.can_family = AF_CAN;
+    addr.can_ifindex = ifr.ifr_ifindex;
+
+    int enableCanFd = 1;
+    if( fd && setsockopt( canSocket, SOL_CAN_RAW, CAN_RAW_FD_FRAMES,
+            &enableCanFd, sizeof(enableCanFd) ) )
+        return -2;
+
+    if( bind( canSocket, (struct sockaddr*)&addr, sizeof(addr) ) < 0 )
+        return -3;
+
+    return canSocket;
+}
+
+/**
+ * @brief Close specified socketcan socket.
+ * 
+ * @param socket Socket identifer as returned from can::connect().
+ * 
+ * @return false If socket close failed
+ */
+bool can_close( const int socket )
+{
+    return close( socket ) >= 0;
+}
+
+/**
+ * @brief Passes call to can::_read<can_frame>() to read standard CAN frame.
+ * 
+ * @pre must call connect() successfully first.
+ * @param socket Socket identifer as returned from can::connect().
+ * @return const can_frame 
+ */
+bool can_read( const int socket, struct can_frame* frame )
+{
+    return read( socket, frame, sizeof(struct can_frame) ) >= 0;
+}
 
-namespace can
+/**
+ * @brief Passes call to can::_read<canfd_frame>() to read CANFD frame.
+ * 
+ * @pre must call connectfd() successfully first.
+ * @param socket Socket identifer as returned from can::connect().
+ * @return const canfd_frame 
+ */
+bool can_readfd( const int socket, struct canfd_frame* frame )
 {
-    /**
-     * @brief Opens socket for CAN bus communication via socketcan. 
-     * Returns socket identifier which is used as an argument for 
-     * future can::read(), can::write() and can::close() calls.
-     * 
-     * @throws std::runtime_error If socket creation failed.
-     * @throws std::runtime_error If could not enable CANFD.
-     * @throws std::runtime_error If could not bind socket.
-     * 
-     * @param fd Open as normal CAN or CANFD.
-     * @param channel Network channel to use, e.g. can0 or vcan0.
-     * @return const int Socket identifier.
-     */
-    const int _connect( const bool fd, const std::string& channel )
-    {
-        const int canSocket = socket( PF_CAN, SOCK_RAW, CAN_RAW );
-        if( canSocket < 0 )
-            throw std::runtime_error( "Create socket failed" );
-
-        struct ifreq ifr;
-        std::strncpy( ifr.ifr_name, channel.c_str(), sizeof(ifr.ifr_name)-1 );
-        ioctl( canSocket, SIOCGIFINDEX, &ifr );
-
-        struct sockaddr_can addr;
-        std::memset( &addr, 0, sizeof(addr) );
-        addr.can_family = AF_CAN;
-        addr.can_ifindex = ifr.ifr_ifindex;
-
-        int enableCanFd = 1;
-        if( fd && setsockopt( canSocket, SOL_CAN_RAW, CAN_RAW_FD_FRAMES,
-                &enableCanFd, sizeof(enableCanFd) ) )
-            throw std::runtime_error( "Enable CAN FD failed" );
-
-        if( bind( canSocket, reinterpret_cast<sockaddr*>(&addr), sizeof(addr) ) < 0 )
-            throw std::runtime_error( "Bind socket failed" );
-
-        return canSocket;
-    }
-
-    /**
-     * @brief Passes call to can::_connect with fd argument as false.
-     */
-    inline const int connect( const std::string channel="vcan0" )
-    {
-        return _connect( false, channel );
-    }
-
-    /**
-     * @brief Passes call to can::_connect with fd argument as true.
-     */
-    inline const int connectfd( const std::string channel="vcan0" )
-    {
-        return  _connect( true, channel );
-    }
-
-    /**
-     * @brief Close specified socketcan socket.
-     * 
-     * @throws std::runtime_error If close failed.
-     * 
-     * @param socket Socket identifer as returned from can::connect().
-     */
-    void close( const int socket )
-    {
-        if( ::close( socket ) < 0 )
-            throw std::runtime_error( "Socket close failed" );
-    }
-
-    /**
-     * @brief Read next frame from CAN bus.
-     * 
-     * @warning This function will block until a frame is available.
-     * 
-     * @throws std::runtime_error If read failed.
-     * 
-     * @param socket Socket identifer as returned from can::connect().
-     * @return const can_frame 
-     */
-    template<typename FRAME>
-    const FRAME _read( const int socket )
-    {
-        FRAME frame;
-
-        if( read( socket, &frame, sizeof(frame) ) < 0 ) 
-            throw std::runtime_error( "Read failed" );
-
-        return frame;
-    }
-
-    /**
-     * @brief Passes call to can::_read<can_frame>() to read standard CAN frame.
-     * 
-     * @param socket Socket identifer as returned from can::connect().
-     * @return const can_frame 
-     */
-    inline const can_frame read( const int socket )
-    {
-        return _read<can_frame>( socket );
-    }
-
-    /**
-     * @brief Passes call to can::_read<canfd_frame>() to read CANFD frame.
-     * 
-     * @param socket Socket identifer as returned from can::connect().
-     * @return const canfd_frame 
-     */
-    inline const canfd_frame readfd( const int socket )
-    {
-        return _read<canfd_frame>( socket );
-    }
-
-    /**
-     * @brief Send CAN frame.
-     * 
-     * @throws std::runtime_error If write failed. 
-     * 
-     * @tparam FRAME can_frame or canfd_frame
-     * @param socket Socket identifer as returned from can::connect().
-     * @param frame CAN or CANFD frame to be sent.
-     * @param numBytes Number of bytes to be written.
-     */
-    template<typename FRAME>
-    void _write( const int socket, const FRAME& frame, const uint8_t numBytes )
-    {
-        if( write( socket, &frame, numBytes ) != numBytes )
-            std::runtime_error( "Write failed" );
-    }
-
-    /**
-     * @brief Passes call to can::_write<can_frame>() to write standard CAN frame.
-     * 
-     * @param socket Socket identifer as returned from can::connect().
-     * @param frame CAN frame to be sent.
-     */
-    void write( const int socket, const can_frame& frame )
-    {
-        // 8 bytes for the frame header and the rest for the actual data.
-        _write( socket, frame, sizeof(can_frame) );
-    }
-
-    /**
-     * @brief Passes call to can::_write<canfd_frame>() to write CANFD frame.
-     * 
-     * @param socket Socket identifer as returned from can::connect().
-     * @param frame CANFD frame to be sent.
-     */
-    void write( const int socket, const canfd_frame& frame )
-    {
-        // 8 bytes for the frame header and the rest for the actual data.
-        _write( socket, frame, sizeof(canfd_frame) );
-    }
-
-
-    std::ostream& operator<<( std::ostream &os, const can_frame& frame )
-    {
-        os << "0x" << std::setw(3) << std::hex << frame.can_id << 
-            " [" << static_cast<int>(frame.can_dlc) << ']';
-        for( int i=0; i<frame.can_dlc; ++i )
-            os << ' ' << std::uppercase << std::setfill('0') << std::setw(2)
-               << static_cast<int>(frame.data[i]);
-
-        return os;
-    }
-
-    std::ostream& operator<<( std::ostream &os, const canfd_frame& frame )
-    {
-        os << "0x" << std::setw(3) << std::hex << frame.can_id << 
-            " [" << static_cast<int>(frame.len) << ']';
-        os << std::uppercase << std::setfill('0') << std::setw(2);
-        for( int i=0; i<frame.len; ++i )
-            os << ' ' << std::uppercase << std::setfill('0') << std::setw(2)
-               << static_cast<int>(frame.data[i]);
-
-        return os;
-    }
+    return read( socket, frame, sizeof(struct canfd_frame) ) >= 0;
 }
 
+/**
+ * @brief Passes call to can::_write<can_frame>() to write standard CAN frame.
+ * 
+ * @param socket Socket identifer as returned from can::connect().
+ * @param frame CAN frame to be sent.
+ */
+bool can_write( const int socket, struct can_frame* frame )
+{
+    return write( socket, &frame, sizeof(struct can_frame) ) == sizeof(struct can_frame);
+}
+
+/**
+ * @brief Passes call to can::_write<canfd_frame>() to write CANFD frame.
+ * 
+ * @param socket Socket identifer as returned from can::connect().
+ * @param frame CANFD frame to be sent.
+ */
+bool can_writefd( const int socket, struct canfd_frame* frame )
+{
+    return write( socket, &frame, sizeof(struct canfd_frame) ) == sizeof(struct canfd_frame);
+}
+
+/*
+std::ostream& operator<<( std::ostream &os, const can_frame& frame )
+{
+    os << "0x" << std::setw(3) << std::hex << frame.can_id << 
+        " [" << static_cast<int>(frame.can_dlc) << ']';
+    for( int i=0; i<frame.can_dlc; ++i )
+        os << ' ' << std::uppercase << std::setfill('0') << std::setw(2)
+            << static_cast<int>(frame.data[i]);
+
+    return os;
+}
+
+std::ostream& operator<<( std::ostream &os, const canfd_frame& frame )
+{
+    os << "0x" << std::setw(3) << std::hex << frame.can_id << 
+        " [" << static_cast<int>(frame.len) << ']';
+    os << std::uppercase << std::setfill('0') << std::setw(2);
+    for( int i=0; i<frame.len; ++i )
+        os << ' ' << std::uppercase << std::setfill('0') << std::setw(2)
+            << static_cast<int>(frame.data[i]);
+
+    return os;
+}*/
+
 #endif