Revision 16:22169975b5d8, committed 2016-02-09

Comitter:

offroad

Date:

Tue Feb 09 11:56:52 2016 +0000

Parent:

15:10c1be621ad6

Commit message:

initial public release

Changed in this revision

diff -r 10c1be621ad6 -r 22169975b5d8 main.cpp
--- a/main.cpp	Sat Nov 07 15:46:54 2015 +0000
+++ b/main.cpp	Tue Feb 09 11:56:52 2016 +0000
@@ -10,9 +10,13 @@
 static int FSM_state2 = 0;
 static char FSM_cmd = 'x';
 
-static void FSM_handleChar(DigitalOut* gpo, char inputChar, char* bufOut, int* nOut){
-    // === reset reply ===
-    *nOut = 0;
+static void FSM_reset(){
+    FSM_state1 = FSM_STATE_IDLE;
+    FSM_state2 = 0;
+    FSM_cmd = 'x';
+}
+
+static void FSM_handleChar(DigitalOut* gpo, char inputChar, char** bufOut){
 
     // === handle incoming char ===
     switch (FSM_state1){
@@ -50,9 +54,9 @@
                         goto reset; // success
                     case '?':
                         // === query GPO state (verify) ===
-                        bufOut[(*nOut)++] = *(gpo+ixGpio) ? '1' : '0';
-                        bufOut[(*nOut)++] = 13;
-                        bufOut[(*nOut)++] = 10;
+                        *((*bufOut)++) = *(gpo+ixGpio) ? '1' : '0';
+                        *((*bufOut)++) = 13;
+                        *((*bufOut)++) = 10;
                         goto reset; // success   
                     default:
                         goto reset; // invalid command byte
@@ -72,22 +76,20 @@
             goto lockup;
     } // switch FSM_state1
 
-    // === internal error. May never be reached ===
+    // === internal error. Should never be reached. ===
 lockup: 
     goto lockup; 
 
     // === reset state machine (on completion and any invalid input ===
 reset:
-    FSM_state1 = FSM_STATE_IDLE;
-    FSM_state2 = 0;
-    FSM_cmd = 'x';
+    FSM_reset();
 
 doneCont:
     return;
 }
 
 int main() {
-    printf("\r\nGPIO server v2 20151106 mn\r\n");
+    printf("\r\nLANGPIO server v2.1 20151107 mn\r\n");
     fflush(stdout);
     static DigitalOut myGpo[NPORTS] = {
         DigitalOut(LED1),
@@ -155,7 +157,8 @@
         
         printf("Connection from: %s\n", client.get_address());
         client.send_all(">\r\n", 3);
-
+        FSM_reset();
+        
         // === main loop ===
         while (true) {
 
@@ -164,19 +167,34 @@
 
             // === detect connection break ===
             if (n < 0)
-                break;
+                goto conn_exit;
             
-            // === handle incoming data ===
+            // maximum length of a single reply. Anything longer will be split.
+            #define MAX_PACKETLEN (1024)
+            // maximum length of a single message to guarantee there is enough output buffer
+            #define MAX_MSGLEN (16)
+            char bufOut[MAX_PACKETLEN];
+            char* pWriteStart = &bufOut[0];
+            char* pWrite = pWriteStart;
+
+            // === iterate over input characters ===
             int ix;
-            char bufOut[255];
-            int nOut = 0;
-            for (ix = 0; ix < n; ++ix)
-                FSM_handleChar(&myGpo[0], buffer[ix], bufOut, &nOut);
+            for (ix = 0; ix < n; ++ix){
+                FSM_handleChar(&myGpo[0], buffer[ix], &pWrite);
 
-            // === send reply ===
-            if (nOut > 0)
-                client.send_all(bufOut, nOut);
+                // === send reply, if there is any ===
+                // - when processing last char of incoming packet
+                // - when output buffer is too full
+                int nInBuf = pWrite - pWriteStart;
+                if (nInBuf > 0)
+                    if ((ix == n-1) || (nInBuf > MAX_PACKETLEN - MAX_MSGLEN)){
+                        client.send_all(bufOut, nInBuf);
+                        pWrite = pWriteStart;
+                    }
+            } // for input character
         } // while connection
+        
+    conn_exit:
         client.close();
     } // eternal main loop
 } // void main