Merge remote-tracking branch 't-b/sideband-bug'

This will allow us to work around the push issues pointed out in
https://github.com/msysgit/git/issues/101.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

Documentation/config.txt

@@ -2387,3 +2387,9 @@ 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.

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;