Sample MQTT program - simple send and receive

Dependencies:   C12832 MQTT

Fork of HelloMQTT by MQTT

Revision:
8:a3e3113054a1
diff -r 3de634f2d40c -r a3e3113054a1 Linux-example/LinuxIPStack.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Linux-example/LinuxIPStack.h	Tue May 20 15:08:05 2014 +0000
@@ -0,0 +1,119 @@
+#if !defined(LINUX_IPSTACK_H)
+#define LINUX_IPSTACK_H
+
+class IPStack 
+{
+public:    
+    IPStack()
+    {
+
+    }
+    
+    int Socket_error(const char* aString)
+    {
+
+        if (errno != EINTR && errno != EAGAIN && errno != EINPROGRESS && errno != EWOULDBLOCK)
+        {
+            if (strcmp(aString, "shutdown") != 0 || (errno != ENOTCONN && errno != ECONNRESET))
+                printf("Socket error %s in %s for socket %d\n", strerror(errno), aString, mysock);
+        }
+        return errno;
+    }
+
+    int connect(const char* hostname, int port)
+    {
+        int type = SOCK_STREAM;
+        struct sockaddr_in address;
+        int rc = -1;
+        sa_family_t family = AF_INET;
+        struct addrinfo *result = NULL;
+        struct addrinfo hints = {0, AF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, 0, NULL, NULL, NULL};
+
+        if ((rc = getaddrinfo(hostname, NULL, &hints, &result)) == 0)
+        {
+            struct addrinfo* res = result;
+
+            /* prefer ip4 addresses */
+            while (res)
+            {
+                if (res->ai_family == AF_INET)
+                {
+                    result = res;
+                    break;
+                }
+                res = res->ai_next;
+            }
+
+            if (result->ai_family == AF_INET)
+            {
+                address.sin_port = htons(port);
+                address.sin_family = family = AF_INET;
+                address.sin_addr = ((struct sockaddr_in*)(result->ai_addr))->sin_addr;
+            }
+            else
+                rc = -1;
+
+            freeaddrinfo(result);
+        }
+
+        if (rc == 0)
+        {
+            mysock = socket(family, type, 0);
+            if (mysock != -1)
+            {
+                int opt = 1;
+
+                //if (setsockopt(mysock, SOL_SOCKET, SO_NOSIGPIPE, (void*)&opt, sizeof(opt)) != 0)
+                //  printf("Could not set SO_NOSIGPIPE for socket %d", mysock);
+                
+                rc = ::connect(mysock, (struct sockaddr*)&address, sizeof(address));
+            }
+        }
+
+        return rc;
+    }
+
+    int read(char* buffer, int len, int timeout_ms)
+    {
+        struct timeval interval = {timeout_ms / 1000, (timeout_ms % 1000) * 1000};
+        if (interval.tv_sec < 0 || (interval.tv_sec == 0 && interval.tv_usec <= 0))
+        {
+            interval.tv_sec = 0;
+            interval.tv_usec = 100;
+        }
+
+        setsockopt(mysock, SOL_SOCKET, SO_RCVTIMEO, (char *)&interval, sizeof(struct timeval));
+
+        //printf("reading %d bytes\n", len);
+        int rc = ::recv(mysock, buffer, (size_t)len, 0);
+        if (rc == -1)
+            Socket_error("read");
+        //printf("read %d bytes\n", rc);
+        return rc;
+    }
+    
+    int write(char* buffer, int len, int timeout)
+    {
+        struct timeval tv;
+
+        tv.tv_sec = 0;  /* 30 Secs Timeout */
+        tv.tv_usec = timeout * 1000;  // Not init'ing this can cause strange errors
+
+        setsockopt(mysock, SOL_SOCKET, SO_RCVTIMEO, (char *)&tv,sizeof(struct timeval));
+        int rc = ::write(mysock, buffer, len);
+        //printf("write rc %d\n", rc);
+        return rc;
+    }
+
+    int disconnect()
+    {
+        return ::close(mysock);
+    }
+    
+private:
+
+    int mysock; 
+    
+};
+
+#endif
\ No newline at end of file