From 6c81a9908206799ccbc9a17bde17f1d766a8eef4 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Martin=20Storsj=C3=B6?= Date: Tue, 1 Dec 2009 12:33:39 +0200 Subject: [PATCH] Allow curl to rewind the RPC read buffer When using multi-pass authentication methods, the curl library may need to rewind the read buffers used for providing data to HTTP POST, if data has been output before a 401 error is received. This is needed only when the first request (when the multi-pass authentication method isn't initialized and hasn't received its challenge yet) for a certain curl session is a chunked HTTP POST. As long as the current rpc read buffer is the first one, we're able to rewind without need for additional buffering. The curl library currently starts sending data without waiting for a response to the Expect: 100-continue header, due to a bug in curl that exists up to curl version 7.19.7. If the HTTP server doesn't handle Expect: 100-continue headers properly (e.g. Lighttpd), the library has to start sending data without knowing if the request will be successfully authenticated. In this case, this rewinding solution is not sufficient - the whole request will be sent before the 401 error is received. Signed-off-by: Martin Storsjo Acked-by: Shawn O. Pearce Signed-off-by: Junio C Hamano --- remote-curl.c | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/remote-curl.c b/remote-curl.c index a331bae6c..28b2a316d 100644 --- a/remote-curl.c +++ b/remote-curl.c @@ -290,6 +290,7 @@ struct rpc_state { int out; struct strbuf result; unsigned gzip_request : 1; + unsigned initial_buffer : 1; }; static size_t rpc_out(void *ptr, size_t eltsize, @@ -300,6 +301,7 @@ static size_t rpc_out(void *ptr, size_t eltsize, size_t avail = rpc->len - rpc->pos; if (!avail) { + rpc->initial_buffer = 0; avail = packet_read_line(rpc->out, rpc->buf, rpc->alloc); if (!avail) return 0; @@ -314,6 +316,29 @@ static size_t rpc_out(void *ptr, size_t eltsize, return avail; } +#ifndef NO_CURL_IOCTL +curlioerr rpc_ioctl(CURL *handle, int cmd, void *clientp) +{ + struct rpc_state *rpc = clientp; + + switch (cmd) { + case CURLIOCMD_NOP: + return CURLIOE_OK; + + case CURLIOCMD_RESTARTREAD: + if (rpc->initial_buffer) { + rpc->pos = 0; + return CURLIOE_OK; + } + fprintf(stderr, "Unable to rewind rpc post data - try increasing http.postBuffer\n"); + return CURLIOE_FAILRESTART; + + default: + return CURLIOE_UNKNOWNCMD; + } +} +#endif + static size_t rpc_in(const void *ptr, size_t eltsize, size_t nmemb, void *buffer_) { @@ -370,8 +395,13 @@ static int post_rpc(struct rpc_state *rpc) */ headers = curl_slist_append(headers, "Expect: 100-continue"); headers = curl_slist_append(headers, "Transfer-Encoding: chunked"); + rpc->initial_buffer = 1; curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, rpc_out); curl_easy_setopt(slot->curl, CURLOPT_INFILE, rpc); +#ifndef NO_CURL_IOCTL + curl_easy_setopt(slot->curl, CURLOPT_IOCTLFUNCTION, rpc_ioctl); + curl_easy_setopt(slot->curl, CURLOPT_IOCTLDATA, rpc); +#endif if (options.verbosity > 1) { fprintf(stderr, "POST %s (chunked)\n", rpc->service_name); fflush(stderr); -- 2.26.2