Specializing socket class to CAN socket operations.

Move all legacy opening RAW CAN socket operation to socket class. Each operations
on a CAN socket has to be simple and made by the socket class.
Simple BCM socket open operation is implemented.
Future will be to open specialized BCM CAN sockets on demand.

Change-Id: If285b97afb9871245ab1f13cd9f0401fbd9adf95
Signed-off-by: Romain Forlot <romain.forlot@iot.bzh>

2 files changed, 90 insertions, 20 deletions

diff --git a/CAN-binder/low-can-binding/utils/socket.cpp b/CAN-binder/low-can-binding/utils/socket.cpp
index ee64348..e166b8c 100644
--- a/CAN-binder/low-can-binding/utils/socket.cpp
+++ b/CAN-binder/low-can-binding/utils/socket.cpp
@@ -16,24 +16,31 @@
  */
 
 #include <unistd.h>
+#include <string>
+#include <string.h>
+#include <linux/can/raw.h>
+#include <net/if.h>
+#include <sys/ioctl.h>
+
 #include "socket.hpp"
+#include "low-can-binding.hpp"
 
 namespace utils
 {
 	/// @brief Construct a default, invalid, socket.
-	socket_t::socket_t()
+	socketcan_t::socketcan_t()
 		: socket_{INVALID_SOCKET}
 	{}
 
 	/// @brief Construct a socket by moving an existing one.
-	socket_t::socket_t(socket_t&& s)
+	socketcan_t::socketcan_t(socketcan_t&& s)
 		: socket_{s.socket_}
 	{
 		s.socket_ = INVALID_SOCKET;
 	}
 
 	/// @brief Destruct the socket.
-	socket_t::~socket_t()
+	socketcan_t::~socketcan_t()
 	{
 		if(socket_ != INVALID_SOCKET)
 			::close(socket_);
@@ -41,7 +48,7 @@ namespace utils
 
 	/// @brief Test if socket is valid.
 	/// @return true if valid, false otherwise.
-	socket_t::operator bool() const
+	socketcan_t::operator bool() const
 	{
 		return socket_ != INVALID_SOCKET;
 	}
@@ -51,7 +58,7 @@ namespace utils
 	/// @param[in] type Specifies the type of socket to be created.
 	/// @param[in] protocol Specifies a particular protocol to be used with the socket. Specifying a protocol of 0 causes socket() to use an unspecified default protocol appropriate for the requested socket type.
 	/// @return Upon successful completion, shall return a non-negative integer, the socket file descriptor. Otherwise, a value of -1 shall be returned and errno set to indicate the error.
-	int socket_t::open(int domain, int type, int protocol)
+	int socketcan_t::open(int domain, int type, int protocol)
 	{
 		close();
 		socket_ = ::socket(domain, type, protocol);
@@ -60,29 +67,89 @@ namespace utils
 
 	/// @brief Close the socket.
 	/// @return 0 if success.
-	int socket_t::close()
+	int socketcan_t::close()
 	{
 		return socket_ != INVALID_SOCKET ? ::close(socket_) : 0;
 	}
 
 	/// @brief Set socket option.
 	/// @return 0 if success.
-	int socket_t::setopt(int level, int optname, const void* optval, socklen_t optlen)
+	int socketcan_t::setopt(int level, int optname, const void* optval, socklen_t optlen)
 	{
 		return socket_ != INVALID_SOCKET ? ::setsockopt(socket_, level, optname, optval, optlen) : 0;
 	}
 
 	/// @brief Bind the socket.
 	/// @return 0 if success.
-	int socket_t::bind(const struct sockaddr* addr, socklen_t len)
+	int socketcan_t::bind(const struct sockaddr* addr, socklen_t len)
 	{
 		return socket_ != INVALID_SOCKET ? ::bind(socket_, addr, len) : 0;
 	}
 
+	/// @brief Connect the socket.
+	/// @return 0 if success.
+	int socketcan_t::connect(const struct sockaddr* addr, socklen_t len)
+	{
+		return socket_ != INVALID_SOCKET ? ::connect(socket_, addr, len) : 0;
+	}
+
 	/// @brief Get the file descriptor.
 	/// @return The socket's file descriptor
-	int socket_t::socket() const
+	int socketcan_t::socket() const
+	{
+		return socket_;
+	}
+
+	/// @brief Open a raw socket CAN.
+	/// @param[in] device_name is the kernel network device name of the CAN interface.
+	///
+	/// @return Upon successful completion, shall return a non-negative integer, the socket file descriptor. Otherwise, a value of -1 shall be returned and errno set to indicate the error.
+	int socketcan_t::open(std::string device_name, bool bcm)
 	{
+		close();
+		
+		struct ifreq ifr;
+		if(bcm)
+			socket_ = ::socket(PF_CAN, SOCK_DGRAM, CAN_BCM);
+		else
+			socket_ = ::socket(PF_CAN, SOCK_RAW, CAN_RAW);
+
+		// Attempts to open a socket to CAN bus
+		::strcpy(ifr.ifr_name, device_name.c_str());
+		DEBUG(binder_interface, "open: ifr_name is : %s", ifr.ifr_name);
+		if(::ioctl(socket_, SIOCGIFINDEX, &ifr) < 0)
+		{
+			ERROR(binder_interface, "open: ioctl failed. Error was : %s", strerror(errno));
+			close();
+		}
+		else
+		{
+			txAddress_.can_family = AF_CAN;
+			txAddress_.can_ifindex = ifr.ifr_ifindex;
+
+			if(bcm && connect((struct sockaddr *)&txAddress_, sizeof(txAddress_)) < 0)
+			{
+				ERROR(binder_interface, "Connect failed. %s", strerror(errno));
+				close();
+			}
+			// It's a RAW socket request, bind it to txAddress
+			else if(bind((struct sockaddr *)&txAddress_, sizeof(txAddress_)) < 0)
+			{
+				ERROR(binder_interface, "Bind failed. %s", strerror(errno));
+				close();
+			}
+		}
 		return socket_;
 	}
+
+	/// @brief Send a CAN message through the socket.
+	///
+	/// @param[in] f - the CAN FD frame to send
+	///
+	/// @return number of sent bytes if message sent, 0 on invalid socket and -1 if something wrong.
+	ssize_t socketcan_t::send(const struct canfd_frame& f)
+	{
+		return socket_ != INVALID_SOCKET ? ::sendto(socket_, &f, sizeof(struct canfd_frame), 0,
+			(struct sockaddr*)&txAddress_, sizeof(txAddress_)) : 0;
+	}
 }
diff --git a/CAN-binder/low-can-binding/utils/socket.hpp b/CAN-binder/low-can-binding/utils/socket.hpp
index b42eee6..2da2dfe 100644
--- a/CAN-binder/low-can-binding/utils/socket.hpp
+++ b/CAN-binder/low-can-binding/utils/socket.hpp
@@ -23,24 +23,27 @@
 
 namespace utils
 {
-	class socket_t
+	class socketcan_t
 	{
 	public:
-		socket_t();
-		socket_t(const socket_t&) = delete;
-		socket_t(socket_t&&);
-		~socket_t();
+		socketcan_t();
+		socketcan_t(const socketcan_t&) = delete;
+		socketcan_t(socketcan_t&&);
+		~socketcan_t();
 
 		explicit operator bool() const;
 
-		int open(int domain, int type, int protocol);
-		int close();
-		int setopt(int level, int optname, const void* optval, socklen_t optlen);
 		int socket() const;
-		int bind(const struct sockaddr* addr, socklen_t len);
-
+		int open(std::string device_name, bool bcm=false);
+		int setopt(int level, int optname, const void* optval, socklen_t optlen);
+		ssize_t send(const struct canfd_frame& f);
+		int close();
 	private:
 		int socket_;
+		struct sockaddr_can txAddress_; /// < internal member using to bind to the socket
+
+		int open(int domain, int type, int protocol);
+		int bind(const struct sockaddr* addr, socklen_t len);
+		int connect(const struct sockaddr* addr, socklen_t len);
 	};
 }
-