Since commit 0c499ea60f the send-pack builtin uses the side-band-64k capability if advertised by the server. Unfortunately this breaks pushing over the dump git protocol with a windows git client.
The detailed reasons for this breakage are (by courtesy of Jeff Preshing, quoted from https://groups.google.com/d/msg/msysgit/at8D7J-h7mw/eaLujILGUWoJ): ---------------------------------------------------------------------------- MinGW wraps Windows sockets in CRT file descriptors in order to mimic the functionality of POSIX sockets. This causes msvcrt.dll to treat sockets as Installable File System (IFS) handles, calling ReadFile, WriteFile, DuplicateHandle and CloseHandle on them. This approach works well in simple cases on recent versions of Windows, but does not support all usage patterns. In particular, using this approach, any attempt to read & write concurrently on the same socket (from one or more processes) will deadlock in a scenario where the read waits for a response from the server which is only invoked after the write. This is what send_pack currently attempts to do in the use_sideband codepath. ---------------------------------------------------------------------------- The new config option "sendpack.sideband" allows to override the side-band-64k capability of the server. Other transportation methods like ssh and http/https still benefit from the sideband channel, therefore the default value of "sendpack.sideband" is still true. Alternative approaches considered but deemed too invasive: - Rewrite read/write wrappers in mingw.c in order to distinguish between a file descriptor which has a socket behind and a file descriptor which has a file behind. - Turning the capability side-band-64k off completely. This would remove a useful feature for users of non-affected transport protocols. Signed-off-by: Thomas Braun <thomas.br...@byte-physics.de> --- This patch, with a slightly less polished commit message, is already part of msysgit/git see b68e386. A lengthy discussion can be found here [1]. What do you think, is this also for you as upstream interesting? [1]: https://github.com/msysgit/git/issues/101 Documentation/config.txt | 6 ++++++ send-pack.c | 14 +++++++++++++- 2 files changed, 19 insertions(+), 1 deletion(-) diff --git a/Documentation/config.txt b/Documentation/config.txt index 1932e9b..13ff657 100644 --- a/Documentation/config.txt +++ b/Documentation/config.txt @@ -2435,3 +2435,9 @@ web.browser:: Specify a web browser that may be used by some commands. Currently only linkgit:git-instaweb[1] and linkgit:git-help[1] may use it. + +sendpack.sideband:: + Allows to disable the side-band-64k capability for send-pack even + when it is advertised by the server. Makes it possible to work + around a limitation in the git for windows implementation together + with the dump git protocol. Defaults to true. diff --git a/send-pack.c b/send-pack.c index 6129b0f..aace1fc 100644 --- a/send-pack.c +++ b/send-pack.c @@ -12,6 +12,16 @@ #include "version.h" #include "sha1-array.h" +static int config_use_sideband = 1; + +static int send_pack_config(const char *var, const char *value, void *unused) +{ + if (!strcmp("sendpack.sideband", var)) + config_use_sideband = git_config_bool(var, value); + + return 0; +} + static int feed_object(const unsigned char *sha1, int fd, int negative) { char buf[42]; @@ -209,6 +219,8 @@ int send_pack(struct send_pack_args *args, int ret; struct async demux; + git_config(send_pack_config, NULL); + /* Does the other end support the reporting? */ if (server_supports("report-status")) status_report = 1; @@ -216,7 +228,7 @@ int send_pack(struct send_pack_args *args, allow_deleting_refs = 1; if (server_supports("ofs-delta")) args->use_ofs_delta = 1; - if (server_supports("side-band-64k")) + if (config_use_sideband && server_supports("side-band-64k")) use_sideband = 1; if (server_supports("quiet")) quiet_supported = 1; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
