From e14a5ca732ade96c27fdfa81fc873ccc98b59525 Mon Sep 17 00:00:00 2001
From: cskarai <cskarai@freemail.hu>
Date: Sat, 17 Sep 2016 16:45:52 +0200
Subject: [PATCH] Refactored: httpd handling

---
 httpd/httpd.c           | 32 ++++++++++++++++++++++----------
 httpd/httpd.h           |  4 +++-
 web-server/web-server.c | 10 +++++++---
 3 files changed, 32 insertions(+), 14 deletions(-)

diff --git a/httpd/httpd.c b/httpd/httpd.c
index 73c187c..bc16649 100644
--- a/httpd/httpd.c
+++ b/httpd/httpd.c
@@ -366,6 +366,7 @@ static void ICACHE_FLASH_ATTR httpdProcessRequest(HttpdConnData *conn) {
         if (match) {
           //os_printf("Is url index %d\n", i);
           conn->cgiData = NULL;
+	  conn->cgiResponse = NULL;
           conn->cgi = builtInUrls[i].cgiCb;
           conn->cgiArg = builtInUrls[i].cgiArg;
           break;
@@ -627,7 +628,8 @@ void ICACHE_FLASH_ATTR httpdInit(HttpdBuiltInUrl *fixedUrls, int port) {
   espconn_tcp_set_max_con_allow(&httpdConn, MAX_CONN);
 }
 
-int ICACHE_FLASH_ATTR httpdNotify(uint8_t * ip, int port, const void * cgiArg) {
+// looks up connection handle based on ip / port
+HttpdConnData * ICACHE_FLASH_ATTR  httpdLookUpConn(uint8_t * ip, int port) {
   int i;
 
   for (i = 0; i<MAX_CONN; i++)
@@ -643,15 +645,25 @@ int ICACHE_FLASH_ATTR httpdNotify(uint8_t * ip, int port, const void * cgiArg) {
     if (os_memcmp(conn->conn->proto.tcp->remote_ip, ip, 4) != 0)
       continue;
     
-    char sendBuff[MAX_SENDBUFF_LEN];
-    conn->priv->sendBuff = sendBuff;
-    conn->priv->sendBuffLen = 0;
+    return conn;
+  }
+  return NULL;
+}
+
+// this method is used for setting the response of a CGI handler outside of the HTTP callback
+// this method useful at the following scenario:
+//   Browser -> CGI handler -> MCU request
+//   MCU response -> CGI handler -> browser
+// when MCU response arrives, the handler looks up connection based on ip/port and call httpdSetCGIResponse with the data to transmit
+
+int ICACHE_FLASH_ATTR httpdSetCGIResponse(HttpdConnData * conn, void * response) {
+  char sendBuff[MAX_SENDBUFF_LEN];
+  conn->priv->sendBuff = sendBuff;
+  conn->priv->sendBuffLen = 0;
 
-    conn->cgiArg = cgiArg;
-    httpdProcessRequest(conn);
-    conn->cgiArg = NULL;
+  conn->cgiResponse = response;
+  httpdProcessRequest(conn);
+  conn->cgiResponse = NULL;
     
-    return HTTPD_CGI_DONE;
-  }
-  return HTTPD_CGI_NOTFOUND;
+  return HTTPD_CGI_DONE;
 }
diff --git a/httpd/httpd.h b/httpd/httpd.h
index 1b0ed38..32d9394 100644
--- a/httpd/httpd.h
+++ b/httpd/httpd.h
@@ -30,6 +30,7 @@ struct HttpdConnData {
 	const void *cgiArg;
 	void *cgiData;
 	void *cgiPrivData; // Used for streaming handlers storing state between requests
+	void *cgiResponse; // used for forwarding response to the CGI handler
 	HttpdPriv *priv;
 	cgiSendCallback cgi;
 	HttpdPostData *post;
@@ -66,6 +67,7 @@ void ICACHE_FLASH_ATTR httpdEndHeaders(HttpdConnData *conn);
 int ICACHE_FLASH_ATTR httpdGetHeader(HttpdConnData *conn, char *header, char *ret, int retLen);
 int ICACHE_FLASH_ATTR httpdSend(HttpdConnData *conn, const char *data, int len);
 void ICACHE_FLASH_ATTR httpdFlush(HttpdConnData *conn);
-int ICACHE_FLASH_ATTR httpdNotify(uint8_t * ip, int port, const void * cgiArg);
+HttpdConnData * ICACHE_FLASH_ATTR  httpdLookUpConn(uint8_t * ip, int port);
+int ICACHE_FLASH_ATTR  httpdSetCGIResponse(HttpdConnData * conn, void *response);
 
 #endif
diff --git a/web-server/web-server.c b/web-server/web-server.c
index 72ee39c..c1bfb6f 100644
--- a/web-server/web-server.c
+++ b/web-server/web-server.c
@@ -253,14 +253,14 @@ int ICACHE_FLASH_ATTR WEB_CgiJsonHook(HttpdConnData *connData)
 		connData->cgiData = (void *)1;
 	}
 	
-	if( connData->cgiArg != NULL ) // arrived data from MCU
+	if( connData->cgiResponse != NULL ) // data from MCU
 	{
 		char jsonBuf[1500];
 		int  jsonPtr = 0;
 		
 		
 		jsonBuf[jsonPtr++] = '{';
-		CmdRequest * req = (CmdRequest *)(connData->cgiArg);
+		CmdRequest * req = (CmdRequest *)(connData->cgiResponse);
 		
 		int c = 2;
 		while( c++ < cmdGetArgc(req) )
@@ -378,5 +378,9 @@ void ICACHE_FLASH_ATTR WEB_Data(CmdPacket *cmd)
 	uint16_t port;
 	cmdPopArg(&req, &port, 2);
 	
-	httpdNotify(ip, port, &req);
+	HttpdConnData * conn = httpdLookUpConn(ip, port);
+	if( conn != NULL && conn->cgi == WEB_CgiJsonHook ) // make sure that the right CGI handler will be called
+		httpdSetCGIResponse( conn, &req );
+	else
+		os_printf("WEB response ignored as no valid http connection found for the request!\n");
 }