[PATCH v2 2/3] git-remote-fd

From

ILIlari Liusvaara <ilari.liusvaara@elisanet.fi>

Date

Sep 30, 2010, 11:52 UTC

Message-ID

<1285847579-21954-3-git-send-email-ilari.liusvaara@elisanet.fi>

In-Reply-To

<1285847579-21954-1-git-send-email-ilari.liusvaara@elisanet.fi>

Signed-off-by: Ilari Liusvaara <ilari.liusvaara@elisanet.fi>
---
 Documentation/git-remote-fd.txt |   57 +++++++++++++++++++++++++
 Makefile                        |    1 +
 builtin.h                       |    1 +
 builtin/remote-fd.c             |   88 +++++++++++++++++++++++++++++++++++++++
 git.c                           |    1 +
 5 files changed, 148 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/git-remote-fd.txt
 create mode 100644 builtin/remote-fd.c

diff --git a/Documentation/git-remote-fd.txt b/Documentation/git-remote-fd.txt
new file mode 100644
index 0000000..12e588a
--- /dev/null
+++ b/Documentation/git-remote-fd.txt
@@ -0,0 +1,57 @@
+git-remote-fd(1)
+=================
+
+NAME
+----
+git-remote-fd - Reflect smart transport back to caller.
+
+
+SYNOPSIS
+--------
+"fd::<fd>[/<anything>]" or "fd::<infd>,<outfd>[/<anything>]" (as URL)
+
+DESCRIPTION
+-----------
+This command uses specified file descriptors to connect to remote git server.
+
+If just <fd> is specified, <fd> is assumed to be socket that is
+transparently connected to git server program.
+
+If <infd> and <outfd> are specified, <infd> is assumed to be pipe from
+git server program and <outfd> is assumed to be pipe to git server program.
+
+It is assumed that any handshaking procedures have already been completed
+(such as sending service request for git://).
+
+<anything> can be any string. It is ignored. It is meant for provoding
+information to user in form of "URL".
+
+ENVIRONMENT VARIABLES:
+----------------------
+
+$GIT_TRANSLOOP_DEBUG (passed to git)::
+	If set, prints debugging information about various reads/writes.
+
+
+EXAMPLES:
+---------
+"fd::17"::
+	Connect using socket in file descriptor #17.
+
+"fd::17/foo"::
+	Same as above.
+
+"fd::7,8"::
+	Connect using pipes in file descriptors #7 and #8. The incoming
+	pipe is at fd #7 and the outgoing pipe at fd #8.
+
+"fd::7,8/bar"::
+	Same as above.
+
+Documentation
+--------------
+Documentation by Ilari Liusvaara.
+
+GIT
+---
+Part of the linkgit:git[1] suite
diff --git a/Makefile b/Makefile
index 8a56b9a..7da54d7 100644
--- a/Makefile
+++ b/Makefile
@@ -728,6 +728,7 @@ BUILTIN_OBJS += builtin/read-tree.o
 BUILTIN_OBJS += builtin/receive-pack.o
 BUILTIN_OBJS += builtin/reflog.o
 BUILTIN_OBJS += builtin/remote.o
+BUILTIN_OBJS += builtin/remote-fd.o
 BUILTIN_OBJS += builtin/replace.o
 BUILTIN_OBJS += builtin/rerere.o
 BUILTIN_OBJS += builtin/reset.o
diff --git a/builtin.h b/builtin.h
index f2a25a0..748cc13 100644
--- a/builtin.h
+++ b/builtin.h
@@ -140,5 +140,6 @@ extern int cmd_verify_pack(int argc, const char **argv, const char *prefix);
 extern int cmd_show_ref(int argc, const char **argv, const char *prefix);
 extern int cmd_pack_refs(int argc, const char **argv, const char *prefix);
 extern int cmd_replace(int argc, const char **argv, const char *prefix);
+extern int cmd_remote_fd(int argc, const char **argv, const char *prefix);
 
 #endif
diff --git a/builtin/remote-fd.c b/builtin/remote-fd.c
new file mode 100644
index 0000000..08ff522
--- /dev/null
+++ b/builtin/remote-fd.c
@@ -0,0 +1,88 @@
+#include "git-compat-util.h"
+#include "transport.h"
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <unistd.h>
+
+
+/*
+ * URL syntax:
+ *	'fd::<inoutfd>[/<anything>]'		Read/write socket pair
+ *						<inoutfd>.
+ *	'fd::<infd>,<outfd>[/<anything>]'	Read pipe <infd> and write
+ *						pipe <outfd>.
+ *	[foo] indicates 'foo' is optional. <anything> is any string.
+ *
+ * The data output to <outfd>/<inoutfd> should be passed unmolested to
+ * git-receive-pack/git-upload-pack/git-upload-archive and output of
+ * git-receive-pack/git-upload-pack/git-upload-archive should be passed
+ * unmolested to <infd>/<inoutfd>.
+ *
+ */
+
+int input_fd = -1;
+int output_fd = -1;
+
+#define MAXCOMMAND 4096
+
+static int command_loop()
+{
+	char buffer[MAXCOMMAND];
+
+	while (1) {
+		if (!fgets(buffer, MAXCOMMAND - 1, stdin))
+			exit(0);
+		//Strip end of line characters.
+		while (isspace((unsigned char)buffer[strlen(buffer) - 1]))
+			buffer[strlen(buffer) - 1] = 0;
+
+		if (!strcmp(buffer, "capabilities")) {
+			printf("*connect\n\n");
+			fflush(stdout);
+		} else if (!strncmp(buffer, "connect ", 8)) {
+			printf("\n");
+			fflush(stdout);
+			return bidirectional_transfer_loop(input_fd,
+				output_fd);
+		} else {
+			fprintf(stderr, "Bad command");
+			return 1;
+		}
+	}
+}
+
+int cmd_remote_fd(int argc, const char **argv, const char *prefix)
+{
+	char* end;
+	unsigned long r;
+
+	if (argc < 3) {
+		fprintf(stderr, "Error: URL missing");
+		exit(1);
+	}
+
+	r = strtoul(argv[2], &end, 10);
+	input_fd = (int)r;
+
+	if ((*end != ',' && *end !='/' && *end) || end == argv[2]) {
+		fprintf(stderr, "Error: Bad URL syntax");
+		exit(1);
+	}
+
+	if (*end == '/' || !*end) {
+		output_fd = input_fd;
+	} else {
+		char* end2;
+		r = strtoul(end + 1, &end2, 10);
+		output_fd = (int)r;
+
+		if ((*end2 !='/' && *end2) || end2 == end + 1) {
+			fprintf(stderr, "Error: Bad URL syntax");
+			exit(1);
+		}
+	}
+
+	return command_loop();
+}
diff --git a/git.c b/git.c
index 50a1401..250ecc5 100644
--- a/git.c
+++ b/git.c
@@ -374,6 +374,7 @@ static void handle_internal_command(int argc, const char **argv)
 		{ "receive-pack", cmd_receive_pack },
 		{ "reflog", cmd_reflog, RUN_SETUP },
 		{ "remote", cmd_remote, RUN_SETUP },
+		{ "remote-fd", cmd_remote_fd, 0 },
 		{ "replace", cmd_replace, RUN_SETUP },
 		{ "repo-config", cmd_config, RUN_SETUP_GENTLY },
 		{ "rerere", cmd_rerere, RUN_SETUP },

-- 
1.7.2.3.401.g919b6e