many changes for fixing a small bug: post requests would not send the post

data.  I took the opportunity to reorganize a bit.


svn:r201

buffer.c

@@ -117,8 +117,10 @@ evbuffer_add_buffer(struct evbuffer *outbuf, struct evbuffer *inbuf)
 	}
 
 	res = evbuffer_add(outbuf, inbuf->buffer, inbuf->off);
-	if (res == 0)
+	if (res == 0) {
+		/* We drain the input buffer on success */
 		evbuffer_drain(inbuf, inbuf->off);
+	}
 
 	return (res);
 }

event.h

@@ -317,7 +317,13 @@ int evtag_unmarshal_timeval(struct evbuffer *evbuf, u_int8_t need_tag,
     struct timeval *ptv);
 
 /*
- * Basic support for HTTP serving
+ * Basic support for HTTP serving.
+ *
+ * As libevent is a library for dealing with event notification and most
+ * interesting applications are networked today, I have often found the
+ * need to write HTTP code.  The following prototypes and definitions provide
+ * an application with a minimal interface for making HTTP requests and for
+ * creating a very simple HTTP server.
  */
 
 /* Response codes */	
@@ -332,6 +338,10 @@ struct evhttp_request;
 /* Start an HTTP server on the specified address and port */
 struct evhttp *evhttp_start(const char *address, u_short port);
 
+/*
+ * Free the previously create HTTP server.  Works only if not requests are
+ * currently being served.
+ */
 void evhttp_free(struct evhttp* http);
 
 /* Set a callback for a specified URI */
@@ -348,12 +358,32 @@ void evhttp_send_reply(struct evhttp_request *, int, const char *,
 
 /* Interfaces for making requests */
 enum evhttp_cmd_type { EVHTTP_REQ_GET, EVHTTP_REQ_POST, EVHTTP_REQ_HEAD };
-enum evhttp_request_kind { EVHTTP_REQUEST, EVHTTP_RESPONSE };
 
 struct evhttp_request *evhttp_request_new(
 	void (*cb)(struct evhttp_request *, void *), void *arg);
 void evhttp_request_free(struct evhttp_request *req);
 
+/* Interfaces for dealing with HTTP headers */
+
+/*
+ * Key-Value pairs.  Can be used for HTTP headers but also for
+ * query argument parsing.
+ */
+struct evkeyval {
+	TAILQ_ENTRY(evkeyval) next;
+
+	char *key;
+	char *value;
+};
+
+TAILQ_HEAD(evkeyvalq, evkeyval);
+
+char *evhttp_find_header(struct evkeyvalq *, const char *);
+void evhttp_remove_header(struct evkeyvalq *, const char *);
+int evhttp_add_header(struct evkeyvalq *, const char *, const char *);
+void evhttp_clear_headers(struct evkeyvalq *);
+
+void evhttp_parse_query(const char *uri, struct evkeyvalq *);
 #ifdef __cplusplus
 }
 #endif

http.c

@@ -177,15 +177,12 @@ evhttp_write_buffer(struct evhttp_request *req, struct evbuffer *buffer,
 	event_add(&req->ev, &tv);
 }
 
-void
+static void
-evhttp_make_header(struct evbuffer *buf, struct evhttp_request *req)
+evhttp_make_header_request(struct evbuffer *buf, struct evhttp_request *req)
 {
-	char line[1024];
+	static char line[1024];
-	struct evkeyval *header;
 	const char *method;
 	
-	/* First we make a few tiny modifications */
-	if (req->kind == EVHTTP_REQUEST) {
 	evhttp_remove_header(req->output_headers, "Accept-Encoding");
 	evhttp_remove_header(req->output_headers, "Proxy-Connection");
 	evhttp_remove_header(req->output_headers, "Connection");
@@ -200,28 +197,46 @@ evhttp_make_header(struct evbuffer *buf, struct evhttp_request *req)
 
 	/* Add the content length on a post request if missing */
 	if (req->type == EVHTTP_REQ_POST &&
-		    evhttp_find_header(req->output_headers,
+	    evhttp_find_header(req->output_headers, "Content-Length") == NULL){
-			"Content-Length") == NULL) {
 		char size[12];
 		snprintf(size, sizeof(size), "%d",
 		    EVBUFFER_LENGTH(req->buffer));
-			evhttp_add_header(req->output_headers,
+		evhttp_add_header(req->output_headers, "Content-Length", size);
-			    "Content-Length", size);
 	}
-	} else {
+}
+
+static void
+evhttp_make_header_response(struct evbuffer *buf, struct evhttp_request *req)
+{
+	static char line[1024];
 	snprintf(line, sizeof(line), "HTTP/%d.%d %d %s\r\n",
 	    req->major, req->minor, req->response_code,
 	    req->response_code_line);
 	evbuffer_add(buf, line, strlen(line));
 
 	/* Potentially add headers */
-		if (evhttp_find_header(req->output_headers,
+	if (evhttp_find_header(req->output_headers, "Content-Type") == NULL) {
-			"Content-Type") == NULL) {
 		evhttp_add_header(req->output_headers,
 		    "Content-Type", "text/html; charset=ISO-8859-1");
 	}
 }
 
+void
+evhttp_make_header(struct evbuffer *buf, struct evhttp_request *req)
+{
+	static char line[1024];
+	struct evkeyval *header;
+
+	/*
+	 * Depending if this is a HTTP request or response, we might need to
+	 * add some new headers or remove existing headers.
+	 */
+	if (req->kind == EVHTTP_REQUEST) {
+		evhttp_make_header_request(buf, req);
+	} else {
+		evhttp_make_header_response(buf, req);
+	}
+
 	TAILQ_FOREACH(header, req->output_headers, next) {
 		snprintf(line, sizeof(line), "%s: %s\r\n",
 		    header->key, header->value);
@@ -230,7 +245,7 @@ evhttp_make_header(struct evbuffer *buf, struct evhttp_request *req)
 	evbuffer_add(buf, "\r\n", 2);
 
 	if (req->kind == EVHTTP_REQUEST) {
-		int len = req->buffer->off;
+		int len = EVBUFFER_LENGTH(req->buffer);
 
 		/* Add the POST data */
 		if (len > 0)
@@ -815,8 +830,12 @@ evhttp_read_header(int fd, short what, void *arg)
 
 /*
  * Creates a TCP connection to the specified port and executes a callback
- * when finished.  Failure of sucess is indicate by the passed connection
+ * when finished.  Failure or sucess is indicate by the passed connection
  * object.
+ *
+ * Although this interface accepts a hostname, it is intended to take
+ * only numeric hostnames so that non-blocking DNS resolution can
+ * happen elsewhere.
  */
 
 struct evhttp_connection *
@@ -865,12 +884,14 @@ evhttp_connect(const char *address, unsigned short port,
 }
 
 /*
- * Don't know if we just want to pass a file descriptor or the evcon object.
+ * Starts an HTTP request on the provided evhttp_connection object.
- * In theory we might use this to queue requests on the connection object.
+ *
+ * In theory we might use this to queue requests on the connection
+ * object.
  */
 
 int
-evhttp_start_request(struct evhttp_connection *evcon,
+evhttp_make_request(struct evhttp_connection *evcon,
     struct evhttp_request *req,
     enum evhttp_cmd_type type, const char *uri)
 {
@@ -897,6 +918,13 @@ evhttp_start_request(struct evhttp_connection *evcon,
 	/* Create the header from the store arguments */
 	evhttp_make_header(evbuf, req);
 
+	/*
+	 * If this was a post request or for other reasons we need to append
+	 * our post data to the request.
+	 */
+	evbuffer_add_buffer(evbuf, req->buffer);
+	   
+
 	/* Schedule the write */
 	req->save_cb = req->cb;
 	req->save_cbarg = req->cb_arg;
@@ -1022,6 +1050,7 @@ evhttp_parse_query(const char *uri, struct evkeyvalq *headers)
 
 	TAILQ_INIT(headers);
 
+	/* No arguments - we are done */
 	if (strchr(uri, '?') == NULL)
 		return;
 

test/regress_http.c

@@ -82,6 +82,7 @@ http_setup(short *pport)
 	if (port == -1)
 		event_errx(1, "Could not start web server");
 
+	/* Register a callback for certain types of requests */
 	evhttp_set_cb(myhttp, "/test", http_basic_cb, NULL);
 
 	*pport = port;
@@ -264,7 +265,7 @@ http_connectcb(struct evhttp_connection *evcon, void *arg)
 	/* Add the information that we care about */
 	evhttp_add_header(req->output_headers, "Host", "somehost");
 	
-	if (evhttp_start_request(evcon, req, EVHTTP_REQ_GET, "/test") == -1) {
+	if (evhttp_make_request(evcon, req, EVHTTP_REQ_GET, "/test") == -1) {
 		fprintf(stdout, "FAILED\n");
 		exit(1);
 	}