[PATCH] Pull refs by HTTP

This adds support for refs to http-pull, both the -w option and reading
the target from a served file.

Signed-off-by: Daniel Barkalow <barkalow@iabervon.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

http-pull.c

@@ -16,6 +16,23 @@ static z_stream stream;
 static int local;
 static int zret;
 
+struct buffer
+{
+        size_t posn;
+        size_t size;
+        void *buffer;
+};
+
+static size_t fwrite_buffer(void *ptr, size_t eltsize, size_t nmemb,
+                            struct buffer *buffer) {
+        size_t size = eltsize * nmemb;
+        if (size > buffer->size - buffer->posn)
+                size = buffer->size - buffer->posn;
+        memcpy(buffer->buffer + buffer->posn, ptr, size);
+        buffer->posn += size;
+        return size;
+}
+
 static size_t fwrite_sha1_file(void *ptr, size_t eltsize, size_t nmemb, 
 			       void *data) {
 	unsigned char expn[4096];
@@ -94,7 +111,32 @@ int fetch(unsigned char *sha1)
 
 int fetch_ref(char *ref, unsigned char *sha1)
 {
-	return -1;
+        char *url, *posn;
+        char hex[42];
+        struct buffer buffer;
+        buffer.size = 41;
+        buffer.posn = 0;
+        buffer.buffer = hex;
+        hex[41] = '\0';
+        
+        curl_easy_setopt(curl, CURLOPT_FILE, &buffer);
+        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
+
+        url = xmalloc(strlen(base) + 6 + strlen(ref));
+        strcpy(url, base);
+        posn = url + strlen(base);
+        strcpy(posn, "refs/");
+        posn += 5;
+        strcpy(posn, ref);
+
+        curl_easy_setopt(curl, CURLOPT_URL, url);
+
+        if (curl_easy_perform(curl))
+                return error("Couldn't get %s for %s\n", url, ref);
+
+        hex[40] = '\0';
+        get_sha1_hex(hex, sha1);
+        return 0;
 }
 
 int main(int argc, char **argv)
@@ -118,11 +160,14 @@ int main(int argc, char **argv)
 			get_history = 1;
 		} else if (argv[arg][1] == 'v') {
 			get_verbosely = 1;
+		} else if (argv[arg][1] == 'w') {
+			write_ref = argv[arg + 1];
+			arg++;
 		}
 		arg++;
 	}
 	if (argc < arg + 2) {
-		usage("git-http-pull [-c] [-t] [-a] [-d] [-v] [--recover] commit-id url");
+		usage("git-http-pull [-c] [-t] [-a] [-d] [-v] [--recover] [-w ref] commit-id url");
 		return 1;
 	}
 	commit_id = argv[arg];