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-rw-r--r--transport-helper.c640
1 files changed, 551 insertions, 89 deletions
diff --git a/transport-helper.c b/transport-helper.c
index ca8fa92e63..6f227e253b 100644
--- a/transport-helper.c
+++ b/transport-helper.c
@@ -7,20 +7,24 @@
#include "revision.h"
#include "quote.h"
#include "remote.h"
+#include "string-list.h"
+#include "thread-utils.h"
static int debug;
-struct helper_data
-{
+struct helper_data {
const char *name;
struct child_process *helper;
FILE *out;
unsigned fetch : 1,
import : 1,
+ export : 1,
option : 1,
push : 1,
connect : 1,
no_disconnect_req : 1;
+ char *export_marks;
+ char *import_marks;
/* These go from remote name (as in "list") to private name */
struct refspec *refspecs;
int refspec_nr;
@@ -74,7 +78,7 @@ static void write_constant(int fd, const char *str)
die_errno("Full write to remote helper failed");
}
-const char *remove_ext_force(const char *url)
+static const char *remove_ext_force(const char *url)
{
if (url) {
const char *colon = strchr(url, ':');
@@ -102,6 +106,13 @@ static struct child_process *get_helper(struct transport *transport)
int refspec_nr = 0;
int refspec_alloc = 0;
int duped;
+ int code;
+ char git_dir_buf[sizeof(GIT_DIR_ENVIRONMENT) + PATH_MAX + 1];
+ const char *helper_env[] = {
+ git_dir_buf,
+ NULL
+ };
+
if (data->helper)
return data->helper;
@@ -111,13 +122,22 @@ static struct child_process *get_helper(struct transport *transport)
helper->out = -1;
helper->err = 0;
helper->argv = xcalloc(4, sizeof(*helper->argv));
- strbuf_addf(&buf, "remote-%s", data->name);
+ strbuf_addf(&buf, "git-remote-%s", data->name);
helper->argv[0] = strbuf_detach(&buf, NULL);
helper->argv[1] = transport->remote->name;
helper->argv[2] = remove_ext_force(transport->url);
- helper->git_cmd = 1;
- if (start_command(helper))
- die("Unable to run helper: git %s", helper->argv[0]);
+ helper->git_cmd = 0;
+ helper->silent_exec_failure = 1;
+
+ snprintf(git_dir_buf, sizeof(git_dir_buf), "%s=%s", GIT_DIR_ENVIRONMENT, get_git_dir());
+ helper->env = helper_env;
+
+ code = start_command(helper);
+ if (code < 0 && errno == ENOENT)
+ die("Unable to find remote helper for '%s'", data->name);
+ else if (code != 0)
+ exit(code);
+
data->helper = helper;
data->no_disconnect_req = 0;
@@ -157,15 +177,27 @@ static struct child_process *get_helper(struct transport *transport)
data->push = 1;
else if (!strcmp(capname, "import"))
data->import = 1;
+ else if (!strcmp(capname, "export"))
+ data->export = 1;
else if (!data->refspecs && !prefixcmp(capname, "refspec ")) {
ALLOC_GROW(refspecs,
refspec_nr + 1,
refspec_alloc);
- refspecs[refspec_nr++] = strdup(buf.buf + strlen("refspec "));
+ refspecs[refspec_nr++] = xstrdup(capname + strlen("refspec "));
} else if (!strcmp(capname, "connect")) {
data->connect = 1;
+ } else if (!prefixcmp(capname, "export-marks ")) {
+ struct strbuf arg = STRBUF_INIT;
+ strbuf_addstr(&arg, "--export-marks=");
+ strbuf_addstr(&arg, capname + strlen("export-marks "));
+ data->export_marks = strbuf_detach(&arg, NULL);
+ } else if (!prefixcmp(capname, "import-marks")) {
+ struct strbuf arg = STRBUF_INIT;
+ strbuf_addstr(&arg, "--import-marks=");
+ strbuf_addstr(&arg, capname + strlen("import-marks "));
+ data->import_marks = strbuf_detach(&arg, NULL);
} else if (mandatory) {
- die("Unknown madatory capability %s. This remote "
+ die("Unknown mandatory capability %s. This remote "
"helper probably needs newer version of Git.\n",
capname);
}
@@ -189,6 +221,7 @@ static int disconnect_helper(struct transport *transport)
{
struct helper_data *data = transport->data;
struct strbuf buf = STRBUF_INIT;
+ int res = 0;
if (data->helper) {
if (debug)
@@ -200,13 +233,13 @@ static int disconnect_helper(struct transport *transport)
close(data->helper->in);
close(data->helper->out);
fclose(data->out);
- finish_command(data->helper);
+ res = finish_command(data->helper);
free((char *)data->helper->argv[0]);
free(data->helper->argv);
free(data->helper);
data->helper = NULL;
}
- return 0;
+ return res;
}
static const char *unsupported_options[] = {
@@ -273,9 +306,8 @@ static void standard_options(struct transport *t)
char buf[16];
int n;
int v = t->verbose;
- int no_progress = v < 0 || (!t->progress && !isatty(2));
- set_helper_option(t, "progress", !no_progress ? "true" : "false");
+ set_helper_option(t, "progress", t->progress ? "true" : "false");
n = snprintf(buf, sizeof(buf), "%d", v + 1);
if (n >= sizeof(buf))
@@ -285,12 +317,13 @@ static void standard_options(struct transport *t)
static int release_helper(struct transport *transport)
{
+ int res = 0;
struct helper_data *data = transport->data;
free_refspec(data->refspec_nr, data->refspecs);
data->refspecs = NULL;
- disconnect_helper(transport);
+ res = disconnect_helper(transport);
free(transport->data);
- return 0;
+ return res;
}
static int fetch_with_fetch(struct transport *transport,
@@ -346,6 +379,33 @@ static int get_importer(struct transport *transport, struct child_process *fasti
return start_command(fastimport);
}
+static int get_exporter(struct transport *transport,
+ struct child_process *fastexport,
+ struct string_list *revlist_args)
+{
+ struct helper_data *data = transport->data;
+ struct child_process *helper = get_helper(transport);
+ int argc = 0, i;
+ memset(fastexport, 0, sizeof(*fastexport));
+
+ /* we need to duplicate helper->in because we want to use it after
+ * fastexport is done with it. */
+ fastexport->out = dup(helper->in);
+ fastexport->argv = xcalloc(5 + revlist_args->nr, sizeof(*fastexport->argv));
+ fastexport->argv[argc++] = "fast-export";
+ fastexport->argv[argc++] = "--use-done-feature";
+ if (data->export_marks)
+ fastexport->argv[argc++] = data->export_marks;
+ if (data->import_marks)
+ fastexport->argv[argc++] = data->import_marks;
+
+ for (i = 0; i < revlist_args->nr; i++)
+ fastexport->argv[argc++] = revlist_args->items[i].string;
+
+ fastexport->git_cmd = 1;
+ return start_command(fastexport);
+}
+
static int fetch_with_import(struct transport *transport,
int nr_heads, struct ref **to_fetch)
{
@@ -369,8 +429,11 @@ static int fetch_with_import(struct transport *transport,
sendline(data, &buf);
strbuf_reset(&buf);
}
- disconnect_helper(transport);
- finish_command(&fastimport);
+
+ write_constant(data->helper->in, "\n");
+
+ if (finish_command(&fastimport))
+ die("Error while running fast-import");
free(fastimport.argv);
fastimport.argv = NULL;
@@ -382,9 +445,11 @@ static int fetch_with_import(struct transport *transport,
if (data->refspecs)
private = apply_refspecs(data->refspecs, data->refspec_nr, posn->name);
else
- private = strdup(posn->name);
- read_ref(private, posn->old_sha1);
- free(private);
+ private = xstrdup(posn->name);
+ if (private) {
+ read_ref(private, posn->old_sha1);
+ free(private);
+ }
}
strbuf_release(&buf);
return 0;
@@ -513,39 +578,112 @@ static int fetch(struct transport *transport,
return -1;
}
-static int push_refs(struct transport *transport,
+static void push_update_ref_status(struct strbuf *buf,
+ struct ref **ref,
+ struct ref *remote_refs)
+{
+ char *refname, *msg;
+ int status;
+
+ if (!prefixcmp(buf->buf, "ok ")) {
+ status = REF_STATUS_OK;
+ refname = buf->buf + 3;
+ } else if (!prefixcmp(buf->buf, "error ")) {
+ status = REF_STATUS_REMOTE_REJECT;
+ refname = buf->buf + 6;
+ } else
+ die("expected ok/error, helper said '%s'\n", buf->buf);
+
+ msg = strchr(refname, ' ');
+ if (msg) {
+ struct strbuf msg_buf = STRBUF_INIT;
+ const char *end;
+
+ *msg++ = '\0';
+ if (!unquote_c_style(&msg_buf, msg, &end))
+ msg = strbuf_detach(&msg_buf, NULL);
+ else
+ msg = xstrdup(msg);
+ strbuf_release(&msg_buf);
+
+ if (!strcmp(msg, "no match")) {
+ status = REF_STATUS_NONE;
+ free(msg);
+ msg = NULL;
+ }
+ else if (!strcmp(msg, "up to date")) {
+ status = REF_STATUS_UPTODATE;
+ free(msg);
+ msg = NULL;
+ }
+ else if (!strcmp(msg, "non-fast forward")) {
+ status = REF_STATUS_REJECT_NONFASTFORWARD;
+ free(msg);
+ msg = NULL;
+ }
+ }
+
+ if (*ref)
+ *ref = find_ref_by_name(*ref, refname);
+ if (!*ref)
+ *ref = find_ref_by_name(remote_refs, refname);
+ if (!*ref) {
+ warning("helper reported unexpected status of %s", refname);
+ return;
+ }
+
+ if ((*ref)->status != REF_STATUS_NONE) {
+ /*
+ * Earlier, the ref was marked not to be pushed, so ignore the ref
+ * status reported by the remote helper if the latter is 'no match'.
+ */
+ if (status == REF_STATUS_NONE)
+ return;
+ }
+
+ (*ref)->status = status;
+ (*ref)->remote_status = msg;
+}
+
+static void push_update_refs_status(struct helper_data *data,
+ struct ref *remote_refs)
+{
+ struct strbuf buf = STRBUF_INIT;
+ struct ref *ref = remote_refs;
+ for (;;) {
+ recvline(data, &buf);
+ if (!buf.len)
+ break;
+
+ push_update_ref_status(&buf, &ref, remote_refs);
+ }
+ strbuf_release(&buf);
+}
+
+static int push_refs_with_push(struct transport *transport,
struct ref *remote_refs, int flags)
{
int force_all = flags & TRANSPORT_PUSH_FORCE;
int mirror = flags & TRANSPORT_PUSH_MIRROR;
struct helper_data *data = transport->data;
struct strbuf buf = STRBUF_INIT;
- struct child_process *helper;
struct ref *ref;
- if (process_connect(transport, 1)) {
- do_take_over(transport);
- return transport->push_refs(transport, remote_refs, flags);
- }
-
- if (!remote_refs)
- return 0;
-
- helper = get_helper(transport);
+ get_helper(transport);
if (!data->push)
return 1;
for (ref = remote_refs; ref; ref = ref->next) {
- if (ref->peer_ref)
- hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
- else if (!mirror)
+ if (!ref->peer_ref && !mirror)
continue;
- ref->deletion = is_null_sha1(ref->new_sha1);
- if (!ref->deletion &&
- !hashcmp(ref->old_sha1, ref->new_sha1)) {
- ref->status = REF_STATUS_UPTODATE;
+ /* Check for statuses set by set_ref_status_for_push() */
+ switch (ref->status) {
+ case REF_STATUS_REJECT_NONFASTFORWARD:
+ case REF_STATUS_UPTODATE:
continue;
+ default:
+ ; /* do nothing */
}
if (force_all)
@@ -567,7 +705,6 @@ static int push_refs(struct transport *transport,
if (buf.len == 0)
return 0;
- transport->verbose = flags & TRANSPORT_PUSH_VERBOSE ? 1 : 0;
standard_options(transport);
if (flags & TRANSPORT_PUSH_DRY_RUN) {
@@ -577,70 +714,84 @@ static int push_refs(struct transport *transport,
strbuf_addch(&buf, '\n');
sendline(data, &buf);
+ strbuf_release(&buf);
- ref = remote_refs;
- while (1) {
- char *refname, *msg;
- int status;
+ push_update_refs_status(data, remote_refs);
+ return 0;
+}
- recvline(data, &buf);
- if (!buf.len)
- break;
+static int push_refs_with_export(struct transport *transport,
+ struct ref *remote_refs, int flags)
+{
+ struct ref *ref;
+ struct child_process *helper, exporter;
+ struct helper_data *data = transport->data;
+ struct string_list revlist_args = STRING_LIST_INIT_NODUP;
+ struct strbuf buf = STRBUF_INIT;
- if (!prefixcmp(buf.buf, "ok ")) {
- status = REF_STATUS_OK;
- refname = buf.buf + 3;
- } else if (!prefixcmp(buf.buf, "error ")) {
- status = REF_STATUS_REMOTE_REJECT;
- refname = buf.buf + 6;
- } else
- die("expected ok/error, helper said '%s'\n", buf.buf);
+ helper = get_helper(transport);
- msg = strchr(refname, ' ');
- if (msg) {
- struct strbuf msg_buf = STRBUF_INIT;
- const char *end;
+ write_constant(helper->in, "export\n");
- *msg++ = '\0';
- if (!unquote_c_style(&msg_buf, msg, &end))
- msg = strbuf_detach(&msg_buf, NULL);
- else
- msg = xstrdup(msg);
- strbuf_release(&msg_buf);
+ strbuf_reset(&buf);
- if (!strcmp(msg, "no match")) {
- status = REF_STATUS_NONE;
- free(msg);
- msg = NULL;
- }
- else if (!strcmp(msg, "up to date")) {
- status = REF_STATUS_UPTODATE;
- free(msg);
- msg = NULL;
- }
- else if (!strcmp(msg, "non-fast forward")) {
- status = REF_STATUS_REJECT_NONFASTFORWARD;
- free(msg);
- msg = NULL;
- }
- }
+ for (ref = remote_refs; ref; ref = ref->next) {
+ char *private;
+ unsigned char sha1[20];
- if (ref)
- ref = find_ref_by_name(ref, refname);
- if (!ref)
- ref = find_ref_by_name(remote_refs, refname);
- if (!ref) {
- warning("helper reported unexpected status of %s", refname);
+ if (!data->refspecs)
continue;
+ private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
+ if (private && !get_sha1(private, sha1)) {
+ strbuf_addf(&buf, "^%s", private);
+ string_list_append(&revlist_args, strbuf_detach(&buf, NULL));
+ }
+ free(private);
+
+ if (ref->deletion) {
+ die("remote-helpers do not support ref deletion");
}
- ref->status = status;
- ref->remote_status = msg;
+ if (ref->peer_ref)
+ string_list_append(&revlist_args, ref->peer_ref->name);
+
}
- strbuf_release(&buf);
+
+ if (get_exporter(transport, &exporter, &revlist_args))
+ die("Couldn't run fast-export");
+
+ if (finish_command(&exporter))
+ die("Error while running fast-export");
+ push_update_refs_status(data, remote_refs);
return 0;
}
+static int push_refs(struct transport *transport,
+ struct ref *remote_refs, int flags)
+{
+ struct helper_data *data = transport->data;
+
+ if (process_connect(transport, 1)) {
+ do_take_over(transport);
+ return transport->push_refs(transport, remote_refs, flags);
+ }
+
+ if (!remote_refs) {
+ fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
+ "Perhaps you should specify a branch such as 'master'.\n");
+ return 0;
+ }
+
+ if (data->push)
+ return push_refs_with_push(transport, remote_refs, flags);
+
+ if (data->export)
+ return push_refs_with_export(transport, remote_refs, flags);
+
+ return -1;
+}
+
+
static int has_attribute(const char *attrs, const char *attr) {
int len;
if (!attrs)
@@ -733,3 +884,314 @@ int transport_helper_init(struct transport *transport, const char *name)
transport->smart_options = &(data->transport_options);
return 0;
}
+
+/*
+ * Linux pipes can buffer 65536 bytes at once (and most platforms can
+ * buffer less), so attempt reads and writes with up to that size.
+ */
+#define BUFFERSIZE 65536
+/* This should be enough to hold debugging message. */
+#define PBUFFERSIZE 8192
+
+/* Print bidirectional transfer loop debug message. */
+static void transfer_debug(const char *fmt, ...)
+{
+ va_list args;
+ char msgbuf[PBUFFERSIZE];
+ static int debug_enabled = -1;
+
+ if (debug_enabled < 0)
+ debug_enabled = getenv("GIT_TRANSLOOP_DEBUG") ? 1 : 0;
+ if (!debug_enabled)
+ return;
+
+ va_start(args, fmt);
+ vsnprintf(msgbuf, PBUFFERSIZE, fmt, args);
+ va_end(args);
+ fprintf(stderr, "Transfer loop debugging: %s\n", msgbuf);
+}
+
+/* Stream state: More data may be coming in this direction. */
+#define SSTATE_TRANSFERING 0
+/*
+ * Stream state: No more data coming in this direction, flushing rest of
+ * data.
+ */
+#define SSTATE_FLUSHING 1
+/* Stream state: Transfer in this direction finished. */
+#define SSTATE_FINISHED 2
+
+#define STATE_NEEDS_READING(state) ((state) <= SSTATE_TRANSFERING)
+#define STATE_NEEDS_WRITING(state) ((state) <= SSTATE_FLUSHING)
+#define STATE_NEEDS_CLOSING(state) ((state) == SSTATE_FLUSHING)
+
+/* Unidirectional transfer. */
+struct unidirectional_transfer {
+ /* Source */
+ int src;
+ /* Destination */
+ int dest;
+ /* Is source socket? */
+ int src_is_sock;
+ /* Is destination socket? */
+ int dest_is_sock;
+ /* Transfer state (TRANSFERING/FLUSHING/FINISHED) */
+ int state;
+ /* Buffer. */
+ char buf[BUFFERSIZE];
+ /* Buffer used. */
+ size_t bufuse;
+ /* Name of source. */
+ const char *src_name;
+ /* Name of destination. */
+ const char *dest_name;
+};
+
+/* Closes the target (for writing) if transfer has finished. */
+static void udt_close_if_finished(struct unidirectional_transfer *t)
+{
+ if (STATE_NEEDS_CLOSING(t->state) && !t->bufuse) {
+ t->state = SSTATE_FINISHED;
+ if (t->dest_is_sock)
+ shutdown(t->dest, SHUT_WR);
+ else
+ close(t->dest);
+ transfer_debug("Closed %s.", t->dest_name);
+ }
+}
+
+/*
+ * Tries to read read data from source into buffer. If buffer is full,
+ * no data is read. Returns 0 on success, -1 on error.
+ */
+static int udt_do_read(struct unidirectional_transfer *t)
+{
+ ssize_t bytes;
+
+ if (t->bufuse == BUFFERSIZE)
+ return 0; /* No space for more. */
+
+ transfer_debug("%s is readable", t->src_name);
+ bytes = read(t->src, t->buf + t->bufuse, BUFFERSIZE - t->bufuse);
+ if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
+ errno != EINTR) {
+ error("read(%s) failed: %s", t->src_name, strerror(errno));
+ return -1;
+ } else if (bytes == 0) {
+ transfer_debug("%s EOF (with %i bytes in buffer)",
+ t->src_name, t->bufuse);
+ t->state = SSTATE_FLUSHING;
+ } else if (bytes > 0) {
+ t->bufuse += bytes;
+ transfer_debug("Read %i bytes from %s (buffer now at %i)",
+ (int)bytes, t->src_name, (int)t->bufuse);
+ }
+ return 0;
+}
+
+/* Tries to write data from buffer into destination. If buffer is empty,
+ * no data is written. Returns 0 on success, -1 on error.
+ */
+static int udt_do_write(struct unidirectional_transfer *t)
+{
+ ssize_t bytes;
+
+ if (t->bufuse == 0)
+ return 0; /* Nothing to write. */
+
+ transfer_debug("%s is writable", t->dest_name);
+ bytes = write(t->dest, t->buf, t->bufuse);
+ if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
+ errno != EINTR) {
+ error("write(%s) failed: %s", t->dest_name, strerror(errno));
+ return -1;
+ } else if (bytes > 0) {
+ t->bufuse -= bytes;
+ if (t->bufuse)
+ memmove(t->buf, t->buf + bytes, t->bufuse);
+ transfer_debug("Wrote %i bytes to %s (buffer now at %i)",
+ (int)bytes, t->dest_name, (int)t->bufuse);
+ }
+ return 0;
+}
+
+
+/* State of bidirectional transfer loop. */
+struct bidirectional_transfer_state {
+ /* Direction from program to git. */
+ struct unidirectional_transfer ptg;
+ /* Direction from git to program. */
+ struct unidirectional_transfer gtp;
+};
+
+static void *udt_copy_task_routine(void *udt)
+{
+ struct unidirectional_transfer *t = (struct unidirectional_transfer *)udt;
+ while (t->state != SSTATE_FINISHED) {
+ if (STATE_NEEDS_READING(t->state))
+ if (udt_do_read(t))
+ return NULL;
+ if (STATE_NEEDS_WRITING(t->state))
+ if (udt_do_write(t))
+ return NULL;
+ if (STATE_NEEDS_CLOSING(t->state))
+ udt_close_if_finished(t);
+ }
+ return udt; /* Just some non-NULL value. */
+}
+
+#ifndef NO_PTHREADS
+
+/*
+ * Join thread, with apporiate errors on failure. Name is name for the
+ * thread (for error messages). Returns 0 on success, 1 on failure.
+ */
+static int tloop_join(pthread_t thread, const char *name)
+{
+ int err;
+ void *tret;
+ err = pthread_join(thread, &tret);
+ if (!tret) {
+ error("%s thread failed", name);
+ return 1;
+ }
+ if (err) {
+ error("%s thread failed to join: %s", name, strerror(err));
+ return 1;
+ }
+ return 0;
+}
+
+/*
+ * Spawn the transfer tasks and then wait for them. Returns 0 on success,
+ * -1 on failure.
+ */
+static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
+{
+ pthread_t gtp_thread;
+ pthread_t ptg_thread;
+ int err;
+ int ret = 0;
+ err = pthread_create(&gtp_thread, NULL, udt_copy_task_routine,
+ &s->gtp);
+ if (err)
+ die("Can't start thread for copying data: %s", strerror(err));
+ err = pthread_create(&ptg_thread, NULL, udt_copy_task_routine,
+ &s->ptg);
+ if (err)
+ die("Can't start thread for copying data: %s", strerror(err));
+
+ ret |= tloop_join(gtp_thread, "Git to program copy");
+ ret |= tloop_join(ptg_thread, "Program to git copy");
+ return ret;
+}
+#else
+
+/* Close the source and target (for writing) for transfer. */
+static void udt_kill_transfer(struct unidirectional_transfer *t)
+{
+ t->state = SSTATE_FINISHED;
+ /*
+ * Socket read end left open isn't a disaster if nobody
+ * attempts to read from it (mingw compat headers do not
+ * have SHUT_RD)...
+ *
+ * We can't fully close the socket since otherwise gtp
+ * task would first close the socket it sends data to
+ * while closing the ptg file descriptors.
+ */
+ if (!t->src_is_sock)
+ close(t->src);
+ if (t->dest_is_sock)
+ shutdown(t->dest, SHUT_WR);
+ else
+ close(t->dest);
+}
+
+/*
+ * Join process, with apporiate errors on failure. Name is name for the
+ * process (for error messages). Returns 0 on success, 1 on failure.
+ */
+static int tloop_join(pid_t pid, const char *name)
+{
+ int tret;
+ if (waitpid(pid, &tret, 0) < 0) {
+ error("%s process failed to wait: %s", name, strerror(errno));
+ return 1;
+ }
+ if (!WIFEXITED(tret) || WEXITSTATUS(tret)) {
+ error("%s process failed", name);
+ return 1;
+ }
+ return 0;
+}
+
+/*
+ * Spawn the transfer tasks and then wait for them. Returns 0 on success,
+ * -1 on failure.
+ */
+static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
+{
+ pid_t pid1, pid2;
+ int ret = 0;
+
+ /* Fork thread #1: git to program. */
+ pid1 = fork();
+ if (pid1 < 0)
+ die_errno("Can't start thread for copying data");
+ else if (pid1 == 0) {
+ udt_kill_transfer(&s->ptg);
+ exit(udt_copy_task_routine(&s->gtp) ? 0 : 1);
+ }
+
+ /* Fork thread #2: program to git. */
+ pid2 = fork();
+ if (pid2 < 0)
+ die_errno("Can't start thread for copying data");
+ else if (pid2 == 0) {
+ udt_kill_transfer(&s->gtp);
+ exit(udt_copy_task_routine(&s->ptg) ? 0 : 1);
+ }
+
+ /*
+ * Close both streams in parent as to not interfere with
+ * end of file detection and wait for both tasks to finish.
+ */
+ udt_kill_transfer(&s->gtp);
+ udt_kill_transfer(&s->ptg);
+ ret |= tloop_join(pid1, "Git to program copy");
+ ret |= tloop_join(pid2, "Program to git copy");
+ return ret;
+}
+#endif
+
+/*
+ * Copies data from stdin to output and from input to stdout simultaneously.
+ * Additionally filtering through given filter. If filter is NULL, uses
+ * identity filter.
+ */
+int bidirectional_transfer_loop(int input, int output)
+{
+ struct bidirectional_transfer_state state;
+
+ /* Fill the state fields. */
+ state.ptg.src = input;
+ state.ptg.dest = 1;
+ state.ptg.src_is_sock = (input == output);
+ state.ptg.dest_is_sock = 0;
+ state.ptg.state = SSTATE_TRANSFERING;
+ state.ptg.bufuse = 0;
+ state.ptg.src_name = "remote input";
+ state.ptg.dest_name = "stdout";
+
+ state.gtp.src = 0;
+ state.gtp.dest = output;
+ state.gtp.src_is_sock = 0;
+ state.gtp.dest_is_sock = (input == output);
+ state.gtp.state = SSTATE_TRANSFERING;
+ state.gtp.bufuse = 0;
+ state.gtp.src_name = "stdin";
+ state.gtp.dest_name = "remote output";
+
+ return tloop_spawnwait_tasks(&state);
+}