1 files changed, 127 insertions, 38 deletions

diff --git a/transport-helper.c b/transport-helper.c
index 6f227e253b..63cabc37e3 100644
--- a/transport-helper.c
+++ b/transport-helper.c
@@ -9,6 +9,9 @@
 #include "remote.h"
 #include "string-list.h"
 #include "thread-utils.h"
+#include "sigchain.h"
+#include "argv-array.h"
+#include "refs.h"
 
 static int debug;
 
@@ -18,10 +21,12 @@ struct helper_data {
 	FILE *out;
 	unsigned fetch : 1,
 		import : 1,
+		bidi_import : 1,
 		export : 1,
 		option : 1,
 		push : 1,
 		connect : 1,
+		signed_tags : 1,
 		no_disconnect_req : 1;
 	char *export_marks;
 	char *import_marks;
@@ -43,7 +48,7 @@ static void sendline(struct helper_data *helper, struct strbuf *buffer)
 		die_errno("Full write to remote helper failed");
 }
 
-static int recvline_fh(FILE *helper, struct strbuf *buffer)
+static int recvline_fh(FILE *helper, struct strbuf *buffer, const char *name)
 {
 	strbuf_reset(buffer);
 	if (debug)
@@ -61,7 +66,7 @@ static int recvline_fh(FILE *helper, struct strbuf *buffer)
 
 static int recvline(struct helper_data *helper, struct strbuf *buffer)
 {
-	return recvline_fh(helper->out, buffer);
+	return recvline_fh(helper->out, buffer, helper->name);
 }
 
 static void xchgline(struct helper_data *helper, struct strbuf *buffer)
@@ -100,6 +105,7 @@ static void do_take_over(struct transport *transport)
 static struct child_process *get_helper(struct transport *transport)
 {
 	struct helper_data *data = transport->data;
+	struct argv_array argv = ARGV_ARRAY_INIT;
 	struct strbuf buf = STRBUF_INIT;
 	struct child_process *helper;
 	const char **refspecs = NULL;
@@ -121,11 +127,10 @@ static struct child_process *get_helper(struct transport *transport)
 	helper->in = -1;
 	helper->out = -1;
 	helper->err = 0;
-	helper->argv = xcalloc(4, sizeof(*helper->argv));
-	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);
+	argv_array_pushf(&argv, "git-remote-%s", data->name);
+	argv_array_push(&argv, transport->remote->name);
+	argv_array_push(&argv, remove_ext_force(transport->url));
+	helper->argv = argv_array_detach(&argv, NULL);
 	helper->git_cmd = 0;
 	helper->silent_exec_failure = 1;
 
@@ -177,6 +182,8 @@ static struct child_process *get_helper(struct transport *transport)
 			data->push = 1;
 		else if (!strcmp(capname, "import"))
 			data->import = 1;
+		else if (!strcmp(capname, "bidi-import"))
+			data->bidi_import = 1;
 		else if (!strcmp(capname, "export"))
 			data->export = 1;
 		else if (!data->refspecs && !prefixcmp(capname, "refspec ")) {
@@ -186,6 +193,8 @@ static struct child_process *get_helper(struct transport *transport)
 			refspecs[refspec_nr++] = xstrdup(capname + strlen("refspec "));
 		} else if (!strcmp(capname, "connect")) {
 			data->connect = 1;
+		} else if (!strcmp(capname, "signed-tags")) {
+			data->signed_tags = 1;
 		} else if (!prefixcmp(capname, "export-marks ")) {
 			struct strbuf arg = STRBUF_INIT;
 			strbuf_addstr(&arg, "--export-marks=");
@@ -198,7 +207,7 @@ static struct child_process *get_helper(struct transport *transport)
 			data->import_marks = strbuf_detach(&arg, NULL);
 		} else if (mandatory) {
 			die("Unknown mandatory capability %s. This remote "
-			    "helper probably needs newer version of Git.\n",
+			    "helper probably needs newer version of Git.",
 			    capname);
 		}
 	}
@@ -206,10 +215,11 @@ static struct child_process *get_helper(struct transport *transport)
 		int i;
 		data->refspec_nr = refspec_nr;
 		data->refspecs = parse_fetch_refspec(refspec_nr, refspecs);
-		for (i = 0; i < refspec_nr; i++) {
+		for (i = 0; i < refspec_nr; i++)
 			free((char *)refspecs[i]);
-		}
 		free(refspecs);
+	} else if (data->import || data->bidi_import || data->export) {
+		warning("This remote helper should implement refspec capability.");
 	}
 	strbuf_release(&buf);
 	if (debug)
@@ -220,22 +230,27 @@ static struct child_process *get_helper(struct transport *transport)
 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)
 			fprintf(stderr, "Debug: Disconnecting.\n");
 		if (!data->no_disconnect_req) {
-			strbuf_addf(&buf, "\n");
-			sendline(data, &buf);
+			/*
+			 * Ignore write errors; there's nothing we can do,
+			 * since we're about to close the pipe anyway. And the
+			 * most likely error is EPIPE due to the helper dying
+			 * to report an error itself.
+			 */
+			sigchain_push(SIGPIPE, SIG_IGN);
+			xwrite(data->helper->in, "\n", 1);
+			sigchain_pop(SIGPIPE);
 		}
 		close(data->helper->in);
 		close(data->helper->out);
 		fclose(data->out);
 		res = finish_command(data->helper);
-		free((char *)data->helper->argv[0]);
-		free(data->helper->argv);
+		argv_array_free_detached(data->helper->argv);
 		free(data->helper);
 		data->helper = NULL;
 	}
@@ -369,14 +384,23 @@ static int fetch_with_fetch(struct transport *transport,
 static int get_importer(struct transport *transport, struct child_process *fastimport)
 {
 	struct child_process *helper = get_helper(transport);
+	struct helper_data *data = transport->data;
+	struct argv_array argv = ARGV_ARRAY_INIT;
+	int cat_blob_fd, code;
 	memset(fastimport, 0, sizeof(*fastimport));
 	fastimport->in = helper->out;
-	fastimport->argv = xcalloc(5, sizeof(*fastimport->argv));
-	fastimport->argv[0] = "fast-import";
-	fastimport->argv[1] = "--quiet";
+	argv_array_push(&argv, "fast-import");
+	argv_array_push(&argv, debug ? "--stats" : "--quiet");
 
+	if (data->bidi_import) {
+		cat_blob_fd = xdup(helper->in);
+		argv_array_pushf(&argv, "--cat-blob-fd=%d", cat_blob_fd);
+	}
+	fastimport->argv = argv.argv;
 	fastimport->git_cmd = 1;
-	return start_command(fastimport);
+
+	code = start_command(fastimport);
+	return code;
 }
 
 static int get_exporter(struct transport *transport,
@@ -391,9 +415,11 @@ static int get_exporter(struct transport *transport,
 	/* 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 = xcalloc(6 + revlist_args->nr, sizeof(*fastexport->argv));
 	fastexport->argv[argc++] = "fast-export";
 	fastexport->argv[argc++] = "--use-done-feature";
+	fastexport->argv[argc++] = data->signed_tags ?
+		"--signed-tags=verbatim" : "--signed-tags=warn-strip";
 	if (data->export_marks)
 		fastexport->argv[argc++] = data->export_marks;
 	if (data->import_marks)
@@ -431,12 +457,33 @@ static int fetch_with_import(struct transport *transport,
 	}
 
 	write_constant(data->helper->in, "\n");
+	/*
+	 * remote-helpers that advertise the bidi-import capability are required to
+	 * buffer the complete batch of import commands until this newline before
+	 * sending data to fast-import.
+	 * These helpers read back data from fast-import on their stdin, which could
+	 * be mixed with import commands, otherwise.
+	 */
 
 	if (finish_command(&fastimport))
 		die("Error while running fast-import");
-	free(fastimport.argv);
-	fastimport.argv = NULL;
+	argv_array_free_detached(fastimport.argv);
 
+	/*
+	 * The fast-import stream of a remote helper that advertises
+	 * the "refspec" capability writes to the refs named after the
+	 * right hand side of the first refspec matching each ref we
+	 * were fetching.
+	 *
+	 * (If no "refspec" capability was specified, for historical
+	 * reasons we default to the equivalent of *:*.)
+	 *
+	 * Store the result in to_fetch[i].old_sha1.  Callers such
+	 * as "git fetch" can use the value to write feedback to the
+	 * terminal, populate FETCH_HEAD, and determine what new value
+	 * should be written to peer_ref if the update is a
+	 * fast-forward or this is a forced update.
+	 */
 	for (i = 0; i < nr_heads; i++) {
 		char *private;
 		posn = to_fetch[i];
@@ -496,7 +543,7 @@ static int process_connect_service(struct transport *transport,
 		goto exit;
 
 	sendline(data, &cmdbuf);
-	recvline_fh(input, &cmdbuf);
+	recvline_fh(input, &cmdbuf, name);
 	if (!strcmp(cmdbuf.buf, "")) {
 		data->no_disconnect_req = 1;
 		if (debug)
@@ -578,7 +625,7 @@ static int fetch(struct transport *transport,
 	return -1;
 }
 
-static void push_update_ref_status(struct strbuf *buf,
+static int push_update_ref_status(struct strbuf *buf,
 				   struct ref **ref,
 				   struct ref *remote_refs)
 {
@@ -592,7 +639,7 @@ static void push_update_ref_status(struct strbuf *buf,
 		status = REF_STATUS_REMOTE_REJECT;
 		refname = buf->buf + 6;
 	} else
-		die("expected ok/error, helper said '%s'\n", buf->buf);
+		die("expected ok/error, helper said '%s'", buf->buf);
 
 	msg = strchr(refname, ' ');
 	if (msg) {
@@ -621,6 +668,21 @@ static void push_update_ref_status(struct strbuf *buf,
 			free(msg);
 			msg = NULL;
 		}
+		else if (!strcmp(msg, "already exists")) {
+			status = REF_STATUS_REJECT_ALREADY_EXISTS;
+			free(msg);
+			msg = NULL;
+		}
+		else if (!strcmp(msg, "fetch first")) {
+			status = REF_STATUS_REJECT_FETCH_FIRST;
+			free(msg);
+			msg = NULL;
+		}
+		else if (!strcmp(msg, "needs force")) {
+			status = REF_STATUS_REJECT_NEEDS_FORCE;
+			free(msg);
+			msg = NULL;
+		}
 	}
 
 	if (*ref)
@@ -629,7 +691,7 @@ static void push_update_ref_status(struct strbuf *buf,
 		*ref = find_ref_by_name(remote_refs, refname);
 	if (!*ref) {
 		warning("helper reported unexpected status of %s", refname);
-		return;
+		return 1;
 	}
 
 	if ((*ref)->status != REF_STATUS_NONE) {
@@ -638,11 +700,12 @@ static void push_update_ref_status(struct strbuf *buf,
 		 * status reported by the remote helper if the latter is 'no match'.
 		 */
 		if (status == REF_STATUS_NONE)
-			return;
+			return 1;
 	}
 
 	(*ref)->status = status;
 	(*ref)->remote_status = msg;
+	return !(status == REF_STATUS_OK);
 }
 
 static void push_update_refs_status(struct helper_data *data,
@@ -651,11 +714,24 @@ static void push_update_refs_status(struct helper_data *data,
 	struct strbuf buf = STRBUF_INIT;
 	struct ref *ref = remote_refs;
 	for (;;) {
+		char *private;
+
 		recvline(data, &buf);
 		if (!buf.len)
 			break;
 
-		push_update_ref_status(&buf, &ref, remote_refs);
+		if (push_update_ref_status(&buf, &ref, remote_refs))
+			continue;
+
+		if (!data->refspecs)
+			continue;
+
+		/* propagate back the update to the remote namespace */
+		private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
+		if (!private)
+			continue;
+		update_ref("update by helper", private, ref->new_sha1, NULL, 0, 0);
+		free(private);
 	}
 	strbuf_release(&buf);
 }
@@ -680,6 +756,7 @@ static int push_refs_with_push(struct transport *transport,
 		/* Check for statuses set by set_ref_status_for_push() */
 		switch (ref->status) {
 		case REF_STATUS_REJECT_NONFASTFORWARD:
+		case REF_STATUS_REJECT_ALREADY_EXISTS:
 		case REF_STATUS_UPTODATE:
 			continue;
 		default:
@@ -729,6 +806,14 @@ static int push_refs_with_export(struct transport *transport,
 	struct string_list revlist_args = STRING_LIST_INIT_NODUP;
 	struct strbuf buf = STRBUF_INIT;
 
+	if (!data->refspecs)
+		die("remote-helper doesn't support push; refspec needed");
+
+	if (flags & TRANSPORT_PUSH_DRY_RUN) {
+		if (set_helper_option(transport, "dry-run", "true") != 0)
+			die("helper %s does not support dry-run", data->name);
+	}
+
 	helper = get_helper(transport);
 
 	write_constant(helper->in, "export\n");
@@ -739,22 +824,25 @@ static int push_refs_with_export(struct transport *transport,
 		char *private;
 		unsigned char sha1[20];
 
-		if (!data->refspecs)
-			continue;
+		if (ref->deletion)
+			die("remote-helpers do not support ref deletion");
+
 		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));
+			hashcpy(ref->old_sha1, sha1);
 		}
 		free(private);
 
-		if (ref->deletion) {
+		if (ref->deletion)
 			die("remote-helpers do not support ref deletion");
-		}
 
-		if (ref->peer_ref)
+		if (ref->peer_ref) {
+			if (strcmp(ref->peer_ref->name, ref->name))
+				die("remote-helpers do not support old:new syntax");
 			string_list_append(&revlist_args, ref->peer_ref->name);
-
+		}
 	}
 
 	if (get_exporter(transport, &exporter, &revlist_args))
@@ -894,6 +982,7 @@ int transport_helper_init(struct transport *transport, const char *name)
 #define PBUFFERSIZE 8192
 
 /* Print bidirectional transfer loop debug message. */
+__attribute__((format (printf, 1, 2)))
 static void transfer_debug(const char *fmt, ...)
 {
 	va_list args;
@@ -935,7 +1024,7 @@ struct unidirectional_transfer {
 	int src_is_sock;
 	/* Is destination socket? */
 	int dest_is_sock;
-	/* Transfer state (TRANSFERING/FLUSHING/FINISHED) */
+	/* Transfer state (TRANSFERRING/FLUSHING/FINISHED) */
 	int state;
 	/* Buffer. */
 	char buf[BUFFERSIZE];
@@ -979,7 +1068,7 @@ static int udt_do_read(struct unidirectional_transfer *t)
 		return -1;
 	} else if (bytes == 0) {
 		transfer_debug("%s EOF (with %i bytes in buffer)",
-			t->src_name, t->bufuse);
+			t->src_name, (int)t->bufuse);
 		t->state = SSTATE_FLUSHING;
 	} else if (bytes > 0) {
 		t->bufuse += bytes;
@@ -1043,7 +1132,7 @@ static void *udt_copy_task_routine(void *udt)
 #ifndef NO_PTHREADS
 
 /*
- * Join thread, with apporiate errors on failure. Name is name for the
+ * Join thread, with appropriate 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)
@@ -1109,7 +1198,7 @@ static void udt_kill_transfer(struct unidirectional_transfer *t)
 }
 
 /*
- * Join process, with apporiate errors on failure. Name is name for the
+ * Join process, with appropriate 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)