Multipart upload implementation

esp-link/cgiwebserver.c

@@ -0,0 +1,31 @@
+// Copyright (c) 2015 by Thorsten von Eicken, see LICENSE.txt in the esp-link repo
+
+#include <esp8266.h>
+#include <osapi.h>
+#include "cgi.h"
+#include "cgioptiboot.h"
+#include "multipart.h"
+
+void webServerMultipartCallback(MultipartCmd cmd, char *data, int dataLen, int position)
+{
+  switch(cmd)
+  {
+    case FILE_START:
+      os_printf("CB: File start: %s\n", data);
+      break;
+    case FILE_DATA:
+      os_printf("CB: Data (%d): %s\n", position, data);
+      break;
+    case FILE_DONE:
+      os_printf("CB: Done\n");
+      break;
+  }
+}
+
+MultipartCtx webServerContext = {.callBack = webServerMultipartCallback, .position = 0, .recvPosition = 0, .startTime = 0, .boundaryBuffer = NULL};
+
+int ICACHE_FLASH_ATTR cgiWebServerUpload(HttpdConnData *connData)
+{
+  os_printf("WebServer upload\n");
+  return multipartProcess(&webServerContext, connData);
+}

esp-link/cgiwebserver.h

@@ -0,0 +1,8 @@
+#ifndef CGIWEBSERVER_H
+#define CGIWEBSERVER_H
+
+#include <httpd.h>
+
+int ICACHE_FLASH_ATTR cgiWebServerUpload(HttpdConnData *connData);
+
+#endif /* CGIWEBSERVER_H */

esp-link/main.c

@@ -19,6 +19,7 @@
 #include "cgimqtt.h"
 #include "cgiflash.h"
 #include "cgioptiboot.h"
+#include "cgiwebserver.h"
 #include "auth.h"
 #include "espfs.h"
 #include "uart.h"
@@ -96,6 +97,7 @@ HttpdBuiltInUrl builtInUrls[] = {
 #ifdef MQTT
   { "/mqtt", cgiMqtt, NULL },
 #endif
+  { "/web-server/upload", cgiWebServerUpload, NULL },
   { "*", cgiEspFsHook, NULL }, //Catch-all cgi function for the filesystem
   { NULL, NULL, NULL }
 };

html/web-server.html

@@ -6,6 +6,12 @@
     <div class="content">
       <p>User defined web pages can be uploaded to esp-link. This is useful if esp-link acts as a web server while MCU provides
         the measurement data.</p>
+
+      <form method="post" action="web-server/upload" name="submit" enctype="multipart/form-data">
+        The custom web page to upload: <input type="file" name="webpage">
+        <input type="submit" name="submit" value="Submit">
+      </form>
+      
     </div>
     
   </div>

httpd/httpd.c

@@ -132,6 +132,7 @@ static void ICACHE_FLASH_ATTR httpdRetireConn(HttpdConnData *conn) {
   if (conn->post->buff != NULL) os_free(conn->post->buff);
   conn->cgi = NULL;
   conn->post->buff = NULL;
+  conn->post->multipartBoundary = NULL;
 }
 
 //Stupid li'l helper function that returns the value of a hex char.
@@ -509,6 +510,7 @@ static void ICACHE_FLASH_ATTR httpdRecvCb(void *arg, char *data, unsigned short
       if (data[x] == '\n' && (char *)os_strstr(conn->priv->head, "\r\n\r\n") != NULL) {
         //Indicate we're done with the headers.
         conn->post->len = 0;
+	conn->post->multipartBoundary = NULL;
         //Reset url data
         conn->url = NULL;
         //Iterate over all received headers and parse them.

httpd/multipart.c

@@ -0,0 +1,190 @@
+#include <esp8266.h>
+#include <osapi.h>
+
+#include "multipart.h"
+#include "cgi.h"
+
+#define BOUNDARY_SIZE 100
+
+void multipartAllocBoundaryBuffer(MultipartCtx * context)
+{
+  if( context->boundaryBuffer == NULL )
+    context->boundaryBuffer = (char *)os_malloc(3*BOUNDARY_SIZE + 1);
+  context->boundaryBufferPtr = 0;
+}
+
+void multipartFreeBoundaryBuffer(MultipartCtx * context)
+{
+  if( context->boundaryBuffer != NULL )
+  {
+    os_free(context->boundaryBuffer);
+    context->boundaryBuffer = NULL;
+  }
+}
+
+void multipartProcessBoundaryBuffer(MultipartCtx * context, char * boundary, char * buff, int len, int last)
+{
+  if( len != 0 )
+  {
+    os_memcpy(context->boundaryBuffer + context->boundaryBufferPtr, buff, len);
+    
+    context->boundaryBufferPtr += len;
+    context->boundaryBuffer[context->boundaryBufferPtr] = 0;
+  }
+  
+  while( context->boundaryBufferPtr > 0 )
+  {
+    if( ! last && context->boundaryBufferPtr <= 2 * BOUNDARY_SIZE )
+      return;
+  
+    int dataSize = BOUNDARY_SIZE;
+  
+    char * loc = os_strstr( context->boundaryBuffer, boundary );
+    if( loc != NULL )
+    {
+      int pos = loc - context->boundaryBuffer;
+      if( pos > BOUNDARY_SIZE )
+        loc = NULL;
+      else
+        dataSize = pos;
+    }
+    
+    if( dataSize != 0 )
+    {
+      switch( context->state )
+      {
+        case STATE_SEARCH_HEADER:
+        case STATE_SEARCH_HEADER_END:
+          {
+            char * chr = os_strchr( context->boundaryBuffer, '\n' );
+            if( chr != NULL )
+            {
+              int pos = chr - context->boundaryBuffer + 1;
+              if( pos < dataSize )
+              {
+                dataSize = pos;
+                loc = NULL; // this is not yet the boundary
+              }
+              if( context->state == STATE_SEARCH_HEADER_END )
+              {
+                if( pos == 1 || ( ( pos == 2 ) && ( context->boundaryBuffer[0] == '\r' ) ) ) // empty line?
+                {
+                  context->state = STATE_UPLOAD_FILE;
+                  context->position = 0;
+                }
+              }
+              else if( os_strncmp( context->boundaryBuffer, "Content-Disposition:",  20 ) == 0 )
+              {
+                char * fnam = os_strstr( context->boundaryBuffer, "filename=" );
+                if( fnam != NULL )
+                {
+                  int pos = fnam - context->boundaryBuffer + 9;
+                  if( pos < dataSize )
+                  {
+                    while(context->boundaryBuffer[pos] == ' ') pos++;
+                    if( context->boundaryBuffer[pos] == '"' )
+                    {
+                      pos++;
+                      int start = pos;
+                      while( pos < context->boundaryBufferPtr )
+                      {
+                        if( context->boundaryBuffer[pos] == '"' )
+                          break;
+                        pos++;
+                      }
+                      if( pos < context->boundaryBufferPtr )
+                      {
+                        context->boundaryBuffer[pos] = 0;
+                        os_printf("Uploading file: %s\n", context->boundaryBuffer + start);
+                        context->callBack( FILE_START, context->boundaryBuffer + start, pos - start, 0 );
+                        context->boundaryBuffer[pos] = '"';
+                        context->state = STATE_SEARCH_HEADER_END;
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          break;
+        case STATE_UPLOAD_FILE:
+          {
+            char c = context->boundaryBuffer[dataSize];
+            context->boundaryBuffer[dataSize] = 0; // add terminating zero (for easier handling)
+            context->callBack( FILE_DATA, context->boundaryBuffer, dataSize, context->position );
+            context->boundaryBuffer[dataSize] = c;
+            context->position += dataSize;
+          }
+          break;
+        default:
+          break;
+      }
+    }
+    
+    if( loc != NULL )
+    {
+      dataSize += os_strlen(boundary);
+      if( context->state == STATE_UPLOAD_FILE )
+      {
+        context->callBack( FILE_DONE, NULL, 0, context->position );
+        os_printf("File upload done\n");
+      }
+
+      context->state = STATE_SEARCH_HEADER;
+    }
+    
+    context->boundaryBufferPtr -= dataSize;
+    os_memcpy(context->boundaryBuffer, context->boundaryBuffer + dataSize, context->boundaryBufferPtr);
+  }
+}
+
+int ICACHE_FLASH_ATTR multipartProcess(MultipartCtx * context, HttpdConnData * connData )
+{
+  if (connData->conn==NULL) return HTTPD_CGI_DONE; // Connection aborted. Clean up.
+  
+  if (connData->requestType == HTTPD_METHOD_POST) {
+    HttpdPostData *post = connData->post;
+    
+    if( post->multipartBoundary == NULL )
+    {
+      errorResponse(connData, 404, "Only multipart POST is supported");
+      return HTTPD_CGI_DONE;
+    }
+
+    if( connData->startTime != context->startTime )
+    {
+      // reinitialize, as this is a different request
+      context->position = 0;
+      context->recvPosition = 0;
+      context->startTime = connData->startTime;
+      context->state = STATE_SEARCH_BOUNDARY;
+ 
+      multipartAllocBoundaryBuffer(context);
+    }
+
+    int feed = 0;
+    while( feed < post->buffLen )
+    {
+      int len = post->buffLen - feed;
+      if( len > BOUNDARY_SIZE )
+        len = BOUNDARY_SIZE;
+      multipartProcessBoundaryBuffer(context, post->multipartBoundary, post->buff + feed, len, 0);
+      feed += len;
+    }
+    
+    context->recvPosition += post->buffLen;
+    if( context->recvPosition < post->len )
+      return HTTPD_CGI_MORE;
+
+    multipartProcessBoundaryBuffer(context, post->multipartBoundary, NULL, 0, 1);
+    multipartFreeBoundaryBuffer( context );
+
+    httpdStartResponse(connData, 204);
+    httpdEndHeaders(connData);
+    return HTTPD_CGI_DONE;
+  }
+  else {
+    errorResponse(connData, 404, "Only multipart POST is supported");
+    return HTTPD_CGI_DONE;
+  }
+}

httpd/multipart.h

@@ -0,0 +1,33 @@
+#ifndef MULTIPART_H
+#define MULTIPART_H
+
+#include <httpd.h>
+
+typedef enum {
+  FILE_START,
+  FILE_DATA,
+  FILE_DONE,
+} MultipartCmd;
+
+typedef enum {
+  STATE_SEARCH_BOUNDARY = 0,
+  STATE_SEARCH_HEADER,
+  STATE_SEARCH_HEADER_END,
+  STATE_UPLOAD_FILE
+} MultipartState;
+
+typedef void (* MultipartCallback)(MultipartCmd cmd, char *data, int dataLen, int position);
+
+typedef struct {
+  MultipartCallback callBack;
+  int               position;
+  int               startTime;
+  int               recvPosition;
+  char *            boundaryBuffer;
+  int               boundaryBufferPtr;
+  MultipartState    state;
+} MultipartCtx;
+
+int ICACHE_FLASH_ATTR multipartProcess(MultipartCtx * context, HttpdConnData * post );
+
+#endif /* MULTIPART_H */