use memset to make sure we get a null terminated strings

Author: Damian Kowalewski

unix/yun/yun.c

@@ -40,44 +40,44 @@ int yunReadProvisioningInfo() {
   char value[64];
   if ((socketHandle = tcp_connect("localhost", 5700)) > 0) {
     // read appId
-    buf[0] = '\0';
-    value[0] = '\0';
+    memset(buf, 0, sizeof(buf));
+    memset(value, 0, sizeof(value));
     tcp_write(socketHandle, "{\"command\": \"get\", \"key\": \"appId\"}\n");
-    if (tcp_read(socketHandle, buf, 128, 2)) {
-      getValueFromJSON(buf, "value", value, 64);
+    if (tcp_read(socketHandle, buf, sizeof(buf) - 1, 2)) {
+      getValueFromJSON(buf, "value", value, sizeof(value));
       if(strcmp("null", value) != 0) {
         strncpy(g_cAppID, value, sizeof(g_cAppID));
       }
     }
 
     // read clientKey
-    buf[0] = '\0';
-    value[0] = '\0';
+    memset(buf, 0, sizeof(buf));
+    memset(value, 0, sizeof(value));
     tcp_write(socketHandle, "{\"command\": \"get\", \"key\": \"clientKey\"}\n");
-    if (tcp_read(socketHandle, buf, 128, 2)) {
-      getValueFromJSON(buf, "value", value, 64);
+    if (tcp_read(socketHandle, buf, sizeof(buf) - 1, 2)) {
+      getValueFromJSON(buf, "value", value, sizeof(value));
       if(strcmp("null", value) != 0) {
         strncpy(g_cClientKey, value, sizeof(g_cClientKey));
       }
     }
 
     // read installationId
-    buf[0] = '\0';
-    value[0] = '\0';
+    memset(buf, 0, sizeof(buf));
+    memset(value, 0, sizeof(value));
     tcp_write(socketHandle, "{\"command\": \"get\", \"key\": \"installationId\"}\n");
-    if (tcp_read(socketHandle, buf, 128, 2)) {
-      getValueFromJSON(buf, "value", value, 64);
+    if (tcp_read(socketHandle, buf, sizeof(buf) - 1, 2)) {
+      getValueFromJSON(buf, "value", value, sizeof(value));
       if(strcmp("null", value) != 0) {
         strncpy(g_cInstallationID, value, sizeof(g_cInstallationID));
       }
     }
 
     // read sessionToken
-    buf[0] = '\0';
-    value[0] = '\0';
+    memset(buf, 0, sizeof(buf));
+    memset(value, 0, sizeof(value));
     tcp_write(socketHandle, "{\"command\": \"get\", \"key\": \"sessionToken\"}\n");
-    if (tcp_read(socketHandle, buf, 128, 2)) {
-      getValueFromJSON(buf, "value", value, 64);
+    if (tcp_read(socketHandle, buf, sizeof(buf) - 1, 2)) {
+      getValueFromJSON(buf, "value", value, sizeof(value));
       if(strcmp("null", value) != 0) {
         strncpy(g_cSessionToken, value, sizeof(g_cSessionToken));
       }