From: Shawn O. Pearce <spearce@spearce.org>
Date: Tue, 16 Oct 2007 04:15:25 +0000 (-0400)
Subject: Merge branch 'master' into db/fetch-pack
X-Git-Tag: v1.5.4-rc0~292^2~20
X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=2e13e5d89252ceef606a0a7be32dbf5bea7e5aca;p=git.git

Merge branch 'master' into db/fetch-pack

There's a number of tricky conflicts between master and
this topic right now due to the rewrite of builtin-push.
Junio must have handled these via rerere; I'd rather not
deal with them again so I'm pre-merging master into the
topic.  Besides this topic somehow started to depend on
the strbuf series that was in next, but is now in master.
It no longer compiles on its own without the strbuf API.

* master: (184 commits)
  Whip post 1.5.3.4 maintenance series into shape.
  Minor usage update in setgitperms.perl
  manual: use 'URL' instead of 'url'.
  manual: add some markup.
  manual: Fix example finding commits referencing given content.
  Fix wording in push definition.
  Fix some typos, punctuation, missing words, minor markup.
  manual: Fix or remove em dashes.
  Add a --dry-run option to git-push.
  Add a --dry-run option to git-send-pack.
  Fix in-place editing functions in convert.c
  instaweb: support for Ruby's WEBrick server
  instaweb: allow for use of auto-generated scripts
  Add 'git-p4 commit' as an alias for 'git-p4 submit'
  hg-to-git speedup through selectable repack intervals
  git-svn: respect Subversion's [auth] section configuration values
  gtksourceview2 support for gitview
  fix contrib/hooks/post-receive-email hooks.recipients error message
  Support cvs via git-shell
  rebase -i: use diff plumbing instead of porcelain
  ...

Conflicts:

	Makefile
	builtin-push.c
	rsh.c
---

2e13e5d89252ceef606a0a7be32dbf5bea7e5aca
diff --cc Makefile
index 7dd212a19,d74ac93c1..bb4873d75
--- a/Makefile
+++ b/Makefile
@@@ -232,8 -233,8 +232,8 @@@ SCRIPTS = $(patsubst %.sh,%,$(SCRIPT_SH
  
  # ... and all the rest that could be moved out of bindir to gitexecdir
  PROGRAMS = \
- 	git-convert-objects$X git-fetch-pack$X \
+ 	git-fetch-pack$X \
 -	git-hash-object$X git-index-pack$X git-local-fetch$X \
 +	git-hash-object$X git-index-pack$X \
  	git-fast-import$X \
  	git-daemon$X \
  	git-merge-index$X git-mktag$X git-mktree$X git-patch-id$X \
diff --cc builtin-push.c
index 4ee36c292,141380b85..a552f0dac
--- a/builtin-push.c
+++ b/builtin-push.c
@@@ -6,11 -6,10 +6,11 @@@
  #include "run-command.h"
  #include "builtin.h"
  #include "remote.h"
 +#include "transport.h"
  
- static const char push_usage[] = "git-push [--all] [--tags] [--receive-pack=<git-receive-pack>] [--repo=all] [-f | --force] [-v] [<repository> <refspec>...]";
+ static const char push_usage[] = "git-push [--all] [--dry-run] [--tags] [--receive-pack=<git-receive-pack>] [--repo=all] [-f | --force] [-v] [<repository> <refspec>...]";
  
 -static int all, dry_run, force, thin, verbose;
 +static int all, thin, verbose;
  static const char *receivepack;
  
  static const char **refspec;
@@@ -104,9 -146,13 +104,13 @@@ int cmd_push(int argc, const char **arg
  			continue;
  		}
  		if (!strcmp(arg, "--all")) {
 -			all = 1;
 +			flags |= TRANSPORT_PUSH_ALL;
  			continue;
  		}
+ 		if (!strcmp(arg, "--dry-run")) {
 -			dry_run = 1;
++			flags |= TRANSPORT_PUSH_DRY_RUN;
+ 			continue;
+ 		}
  		if (!strcmp(arg, "--tags")) {
  			add_refspec("refs/tags/*");
  			continue;
diff --cc transport.c
index 46da75407,000000000..e363c11c0
mode 100644,000000..100644
--- a/transport.c
+++ b/transport.c
@@@ -1,819 -1,0 +1,821 @@@
 +#include "cache.h"
 +#include "transport.h"
 +#include "run-command.h"
 +#ifndef NO_CURL
 +#include "http.h"
 +#endif
 +#include "pkt-line.h"
 +#include "fetch-pack.h"
 +#include "walker.h"
 +#include "bundle.h"
 +#include "dir.h"
 +#include "refs.h"
 +
 +/* rsync support */
 +
 +/*
 + * We copy packed-refs and refs/ into a temporary file, then read the
 + * loose refs recursively (sorting whenever possible), and then inserting
 + * those packed refs that are not yet in the list (not validating, but
 + * assuming that the file is sorted).
 + *
 + * Appears refactoring this from refs.c is too cumbersome.
 + */
 +
 +static int str_cmp(const void *a, const void *b)
 +{
 +	const char *s1 = a;
 +	const char *s2 = b;
 +
 +	return strcmp(s1, s2);
 +}
 +
 +/* path->buf + name_offset is expected to point to "refs/" */
 +
 +static int read_loose_refs(struct strbuf *path, int name_offset,
 +		struct ref **tail)
 +{
 +	DIR *dir = opendir(path->buf);
 +	struct dirent *de;
 +	struct {
 +		char **entries;
 +		int nr, alloc;
 +	} list;
 +	int i, pathlen;
 +
 +	if (!dir)
 +		return -1;
 +
 +	memset (&list, 0, sizeof(list));
 +
 +	while ((de = readdir(dir))) {
 +		if (de->d_name[0] == '.' && (de->d_name[1] == '\0' ||
 +				(de->d_name[1] == '.' &&
 +				 de->d_name[2] == '\0')))
 +			continue;
 +		ALLOC_GROW(list.entries, list.nr + 1, list.alloc);
 +		list.entries[list.nr++] = xstrdup(de->d_name);
 +	}
 +	closedir(dir);
 +
 +	/* sort the list */
 +
 +	qsort(list.entries, list.nr, sizeof(char *), str_cmp);
 +
 +	pathlen = path->len;
 +	strbuf_addch(path, '/');
 +
 +	for (i = 0; i < list.nr; i++, strbuf_setlen(path, pathlen + 1)) {
 +		strbuf_addstr(path, list.entries[i]);
 +		if (read_loose_refs(path, name_offset, tail)) {
 +			int fd = open(path->buf, O_RDONLY);
 +			char buffer[40];
 +			struct ref *next;
 +
 +			if (fd < 0)
 +				continue;
 +			next = alloc_ref(path->len - name_offset + 1);
 +			if (read_in_full(fd, buffer, 40) != 40 ||
 +					get_sha1_hex(buffer, next->old_sha1)) {
 +				close(fd);
 +				free(next);
 +				continue;
 +			}
 +			close(fd);
 +			strcpy(next->name, path->buf + name_offset);
 +			(*tail)->next = next;
 +			*tail = next;
 +		}
 +	}
 +	strbuf_setlen(path, pathlen);
 +
 +	for (i = 0; i < list.nr; i++)
 +		free(list.entries[i]);
 +	free(list.entries);
 +
 +	return 0;
 +}
 +
 +/* insert the packed refs for which no loose refs were found */
 +
 +static void insert_packed_refs(const char *packed_refs, struct ref **list)
 +{
 +	FILE *f = fopen(packed_refs, "r");
 +	static char buffer[PATH_MAX];
 +
 +	if (!f)
 +		return;
 +
 +	for (;;) {
 +		int cmp, len;
 +
 +		if (!fgets(buffer, sizeof(buffer), f)) {
 +			fclose(f);
 +			return;
 +		}
 +
 +		if (hexval(buffer[0]) > 0xf)
 +			continue;
 +		len = strlen(buffer);
 +		if (buffer[len - 1] == '\n')
 +			buffer[--len] = '\0';
 +		if (len < 41)
 +			continue;
 +		while ((*list)->next &&
 +				(cmp = strcmp(buffer + 41,
 +				      (*list)->next->name)) > 0)
 +			list = &(*list)->next;
 +		if (!(*list)->next || cmp < 0) {
 +			struct ref *next = alloc_ref(len - 40);
 +			buffer[40] = '\0';
 +			if (get_sha1_hex(buffer, next->old_sha1)) {
 +				warning ("invalid SHA-1: %s", buffer);
 +				free(next);
 +				continue;
 +			}
 +			strcpy(next->name, buffer + 41);
 +			next->next = (*list)->next;
 +			(*list)->next = next;
 +			list = &(*list)->next;
 +		}
 +	}
 +}
 +
 +static struct ref *get_refs_via_rsync(const struct transport *transport)
 +{
 +	struct strbuf buf = STRBUF_INIT, temp_dir = STRBUF_INIT;
 +	struct ref dummy, *tail = &dummy;
 +	struct child_process rsync;
 +	const char *args[5];
 +	int temp_dir_len;
 +
 +	/* copy the refs to the temporary directory */
 +
 +	strbuf_addstr(&temp_dir, git_path("rsync-refs-XXXXXX"));
 +	if (!mkdtemp(temp_dir.buf))
 +		die ("Could not make temporary directory");
 +	temp_dir_len = temp_dir.len;
 +
 +	strbuf_addstr(&buf, transport->url);
 +	strbuf_addstr(&buf, "/refs");
 +
 +	memset(&rsync, 0, sizeof(rsync));
 +	rsync.argv = args;
 +	rsync.stdout_to_stderr = 1;
 +	args[0] = "rsync";
 +	args[1] = (transport->verbose > 0) ? "-rv" : "-r";
 +	args[2] = buf.buf;
 +	args[3] = temp_dir.buf;
 +	args[4] = NULL;
 +
 +	if (run_command(&rsync))
 +		die ("Could not run rsync to get refs");
 +
 +	strbuf_reset(&buf);
 +	strbuf_addstr(&buf, transport->url);
 +	strbuf_addstr(&buf, "/packed-refs");
 +
 +	args[2] = buf.buf;
 +
 +	if (run_command(&rsync))
 +		die ("Could not run rsync to get refs");
 +
 +	/* read the copied refs */
 +
 +	strbuf_addstr(&temp_dir, "/refs");
 +	read_loose_refs(&temp_dir, temp_dir_len + 1, &tail);
 +	strbuf_setlen(&temp_dir, temp_dir_len);
 +
 +	tail = &dummy;
 +	strbuf_addstr(&temp_dir, "/packed-refs");
 +	insert_packed_refs(temp_dir.buf, &tail);
 +	strbuf_setlen(&temp_dir, temp_dir_len);
 +
 +	if (remove_dir_recursively(&temp_dir, 0))
 +		warning ("Error removing temporary directory %s.",
 +				temp_dir.buf);
 +
 +	strbuf_release(&buf);
 +	strbuf_release(&temp_dir);
 +
 +	return dummy.next;
 +}
 +
 +static int fetch_objs_via_rsync(struct transport *transport,
 +				 int nr_objs, struct ref **to_fetch)
 +{
 +	struct strbuf buf = STRBUF_INIT;
 +	struct child_process rsync;
 +	const char *args[8];
 +	int result;
 +
 +	strbuf_addstr(&buf, transport->url);
 +	strbuf_addstr(&buf, "/objects/");
 +
 +	memset(&rsync, 0, sizeof(rsync));
 +	rsync.argv = args;
 +	rsync.stdout_to_stderr = 1;
 +	args[0] = "rsync";
 +	args[1] = (transport->verbose > 0) ? "-rv" : "-r";
 +	args[2] = "--ignore-existing";
 +	args[3] = "--exclude";
 +	args[4] = "info";
 +	args[5] = buf.buf;
 +	args[6] = get_object_directory();
 +	args[7] = NULL;
 +
 +	/* NEEDSWORK: handle one level of alternates */
 +	result = run_command(&rsync);
 +
 +	strbuf_release(&buf);
 +
 +	return result;
 +}
 +
 +static int write_one_ref(const char *name, const unsigned char *sha1,
 +		int flags, void *data)
 +{
 +	struct strbuf *buf = data;
 +	int len = buf->len;
 +	FILE *f;
 +
 +	/* when called via for_each_ref(), flags is non-zero */
 +	if (flags && prefixcmp(name, "refs/heads/") &&
 +			prefixcmp(name, "refs/tags/"))
 +		return 0;
 +
 +	strbuf_addstr(buf, name);
 +	if (safe_create_leading_directories(buf->buf) ||
 +			!(f = fopen(buf->buf, "w")) ||
 +			fprintf(f, "%s\n", sha1_to_hex(sha1)) < 0 ||
 +			fclose(f))
 +		return error("problems writing temporary file %s", buf->buf);
 +	strbuf_setlen(buf, len);
 +	return 0;
 +}
 +
 +static int write_refs_to_temp_dir(struct strbuf *temp_dir,
 +		int refspec_nr, const char **refspec)
 +{
 +	int i;
 +
 +	for (i = 0; i < refspec_nr; i++) {
 +		unsigned char sha1[20];
 +		char *ref;
 +
 +		if (dwim_ref(refspec[i], strlen(refspec[i]), sha1, &ref) != 1)
 +			return error("Could not get ref %s", refspec[i]);
 +
 +		if (write_one_ref(ref, sha1, 0, temp_dir)) {
 +			free(ref);
 +			return -1;
 +		}
 +		free(ref);
 +	}
 +	return 0;
 +}
 +
 +static int rsync_transport_push(struct transport *transport,
 +		int refspec_nr, const char **refspec, int flags)
 +{
 +	struct strbuf buf = STRBUF_INIT, temp_dir = STRBUF_INIT;
 +	int result = 0, i;
 +	struct child_process rsync;
 +	const char *args[8];
 +
 +	/* first push the objects */
 +
 +	strbuf_addstr(&buf, transport->url);
 +	strbuf_addch(&buf, '/');
 +
 +	memset(&rsync, 0, sizeof(rsync));
 +	rsync.argv = args;
 +	rsync.stdout_to_stderr = 1;
 +	args[0] = "rsync";
 +	args[1] = (transport->verbose > 0) ? "-av" : "-a";
 +	args[2] = "--ignore-existing";
 +	args[3] = "--exclude";
 +	args[4] = "info";
 +	args[5] = get_object_directory();;
 +	args[6] = buf.buf;
 +	args[7] = NULL;
 +
 +	if (run_command(&rsync))
 +		return error("Could not push objects to %s", transport->url);
 +
 +	/* copy the refs to the temporary directory; they could be packed. */
 +
 +	strbuf_addstr(&temp_dir, git_path("rsync-refs-XXXXXX"));
 +	if (!mkdtemp(temp_dir.buf))
 +		die ("Could not make temporary directory");
 +	strbuf_addch(&temp_dir, '/');
 +
 +	if (flags & TRANSPORT_PUSH_ALL) {
 +		if (for_each_ref(write_one_ref, &temp_dir))
 +			return -1;
 +	} else if (write_refs_to_temp_dir(&temp_dir, refspec_nr, refspec))
 +		return -1;
 +
 +	i = (flags & TRANSPORT_PUSH_FORCE) ? 2 : 3;
 +	args[i++] = temp_dir.buf;
 +	args[i++] = transport->url;
 +	args[i++] = NULL;
 +	if (run_command(&rsync))
 +		result = error("Could not push to %s", transport->url);
 +
 +	if (remove_dir_recursively(&temp_dir, 0))
 +		warning ("Could not remove temporary directory %s.",
 +				temp_dir.buf);
 +
 +	strbuf_release(&buf);
 +	strbuf_release(&temp_dir);
 +
 +	return result;
 +}
 +
 +/* Generic functions for using commit walkers */
 +
 +static int fetch_objs_via_walker(struct transport *transport,
 +				 int nr_objs, struct ref **to_fetch)
 +{
 +	char *dest = xstrdup(transport->url);
 +	struct walker *walker = transport->data;
 +	char **objs = xmalloc(nr_objs * sizeof(*objs));
 +	int i;
 +
 +	walker->get_all = 1;
 +	walker->get_tree = 1;
 +	walker->get_history = 1;
 +	walker->get_verbosely = transport->verbose >= 0;
 +	walker->get_recover = 0;
 +
 +	for (i = 0; i < nr_objs; i++)
 +		objs[i] = xstrdup(sha1_to_hex(to_fetch[i]->old_sha1));
 +
 +	if (walker_fetch(walker, nr_objs, objs, NULL, NULL))
 +		die("Fetch failed.");
 +
 +	for (i = 0; i < nr_objs; i++)
 +		free(objs[i]);
 +	free(objs);
 +	free(dest);
 +	return 0;
 +}
 +
 +static int disconnect_walker(struct transport *transport)
 +{
 +	struct walker *walker = transport->data;
 +	if (walker)
 +		walker_free(walker);
 +	return 0;
 +}
 +
 +#ifndef NO_CURL
 +static int curl_transport_push(struct transport *transport, int refspec_nr, const char **refspec, int flags) {
 +	const char **argv;
 +	int argc;
 +	int err;
 +
 +	argv = xmalloc((refspec_nr + 11) * sizeof(char *));
 +	argv[0] = "http-push";
 +	argc = 1;
 +	if (flags & TRANSPORT_PUSH_ALL)
 +		argv[argc++] = "--all";
 +	if (flags & TRANSPORT_PUSH_FORCE)
 +		argv[argc++] = "--force";
 +	argv[argc++] = transport->url;
 +	while (refspec_nr--)
 +		argv[argc++] = *refspec++;
 +	argv[argc] = NULL;
 +	err = run_command_v_opt(argv, RUN_GIT_CMD);
 +	switch (err) {
 +	case -ERR_RUN_COMMAND_FORK:
 +		error("unable to fork for %s", argv[0]);
 +	case -ERR_RUN_COMMAND_EXEC:
 +		error("unable to exec %s", argv[0]);
 +		break;
 +	case -ERR_RUN_COMMAND_WAITPID:
 +	case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
 +	case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
 +	case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
 +		error("%s died with strange error", argv[0]);
 +	}
 +	return !!err;
 +}
 +
 +static int missing__target(int code, int result)
 +{
 +	return	/* file:// URL -- do we ever use one??? */
 +		(result == CURLE_FILE_COULDNT_READ_FILE) ||
 +		/* http:// and https:// URL */
 +		(code == 404 && result == CURLE_HTTP_RETURNED_ERROR) ||
 +		/* ftp:// URL */
 +		(code == 550 && result == CURLE_FTP_COULDNT_RETR_FILE)
 +		;
 +}
 +
 +#define missing_target(a) missing__target((a)->http_code, (a)->curl_result)
 +
 +static struct ref *get_refs_via_curl(const struct transport *transport)
 +{
 +	struct buffer buffer;
 +	char *data, *start, *mid;
 +	char *ref_name;
 +	char *refs_url;
 +	int i = 0;
 +
 +	struct active_request_slot *slot;
 +	struct slot_results results;
 +
 +	struct ref *refs = NULL;
 +	struct ref *ref = NULL;
 +	struct ref *last_ref = NULL;
 +
 +	data = xmalloc(4096);
 +	buffer.size = 4096;
 +	buffer.posn = 0;
 +	buffer.buffer = data;
 +
 +	refs_url = xmalloc(strlen(transport->url) + 11);
 +	sprintf(refs_url, "%s/info/refs", transport->url);
 +
 +	http_init();
 +
 +	slot = get_active_slot();
 +	slot->results = &results;
 +	curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
 +	curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
 +	curl_easy_setopt(slot->curl, CURLOPT_URL, refs_url);
 +	curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, NULL);
 +	if (start_active_slot(slot)) {
 +		run_active_slot(slot);
 +		if (results.curl_result != CURLE_OK) {
 +			if (missing_target(&results)) {
 +				free(buffer.buffer);
 +				return NULL;
 +			} else {
 +				free(buffer.buffer);
 +				error("%s", curl_errorstr);
 +				return NULL;
 +			}
 +		}
 +	} else {
 +		free(buffer.buffer);
 +		error("Unable to start request");
 +		return NULL;
 +	}
 +
 +	http_cleanup();
 +
 +	data = buffer.buffer;
 +	start = NULL;
 +	mid = data;
 +	while (i < buffer.posn) {
 +		if (!start)
 +			start = &data[i];
 +		if (data[i] == '\t')
 +			mid = &data[i];
 +		if (data[i] == '\n') {
 +			data[i] = 0;
 +			ref_name = mid + 1;
 +			ref = xmalloc(sizeof(struct ref) +
 +				      strlen(ref_name) + 1);
 +			memset(ref, 0, sizeof(struct ref));
 +			strcpy(ref->name, ref_name);
 +			get_sha1_hex(start, ref->old_sha1);
 +			if (!refs)
 +				refs = ref;
 +			if (last_ref)
 +				last_ref->next = ref;
 +			last_ref = ref;
 +			start = NULL;
 +		}
 +		i++;
 +	}
 +
 +	free(buffer.buffer);
 +
 +	return refs;
 +}
 +
 +static int fetch_objs_via_curl(struct transport *transport,
 +				 int nr_objs, struct ref **to_fetch)
 +{
 +	if (!transport->data)
 +		transport->data = get_http_walker(transport->url);
 +	return fetch_objs_via_walker(transport, nr_objs, to_fetch);
 +}
 +
 +#endif
 +
 +struct bundle_transport_data {
 +	int fd;
 +	struct bundle_header header;
 +};
 +
 +static struct ref *get_refs_from_bundle(const struct transport *transport)
 +{
 +	struct bundle_transport_data *data = transport->data;
 +	struct ref *result = NULL;
 +	int i;
 +
 +	if (data->fd > 0)
 +		close(data->fd);
 +	data->fd = read_bundle_header(transport->url, &data->header);
 +	if (data->fd < 0)
 +		die ("Could not read bundle '%s'.", transport->url);
 +	for (i = 0; i < data->header.references.nr; i++) {
 +		struct ref_list_entry *e = data->header.references.list + i;
 +		struct ref *ref = alloc_ref(strlen(e->name) + 1);
 +		hashcpy(ref->old_sha1, e->sha1);
 +		strcpy(ref->name, e->name);
 +		ref->next = result;
 +		result = ref;
 +	}
 +	return result;
 +}
 +
 +static int fetch_refs_from_bundle(struct transport *transport,
 +			       int nr_heads, struct ref **to_fetch)
 +{
 +	struct bundle_transport_data *data = transport->data;
 +	return unbundle(&data->header, data->fd);
 +}
 +
 +static int close_bundle(struct transport *transport)
 +{
 +	struct bundle_transport_data *data = transport->data;
 +	if (data->fd > 0)
 +		close(data->fd);
 +	free(data);
 +	return 0;
 +}
 +
 +struct git_transport_data {
 +	unsigned thin : 1;
 +	unsigned keep : 1;
 +	int depth;
 +	const char *uploadpack;
 +	const char *receivepack;
 +};
 +
 +static int set_git_option(struct transport *connection,
 +			  const char *name, const char *value)
 +{
 +	struct git_transport_data *data = connection->data;
 +	if (!strcmp(name, TRANS_OPT_UPLOADPACK)) {
 +		data->uploadpack = value;
 +		return 0;
 +	} else if (!strcmp(name, TRANS_OPT_RECEIVEPACK)) {
 +		data->receivepack = value;
 +		return 0;
 +	} else if (!strcmp(name, TRANS_OPT_THIN)) {
 +		data->thin = !!value;
 +		return 0;
 +	} else if (!strcmp(name, TRANS_OPT_KEEP)) {
 +		data->keep = !!value;
 +		return 0;
 +	} else if (!strcmp(name, TRANS_OPT_DEPTH)) {
 +		if (!value)
 +			data->depth = 0;
 +		else
 +			data->depth = atoi(value);
 +		return 0;
 +	}
 +	return 1;
 +}
 +
 +static struct ref *get_refs_via_connect(const struct transport *transport)
 +{
 +	struct git_transport_data *data = transport->data;
 +	struct ref *refs;
 +	int fd[2];
 +	pid_t pid;
 +	char *dest = xstrdup(transport->url);
 +
 +	pid = git_connect(fd, dest, data->uploadpack, 0);
 +
 +	if (pid < 0)
 +		die("Failed to connect to \"%s\"", transport->url);
 +
 +	get_remote_heads(fd[0], &refs, 0, NULL, 0);
 +	packet_flush(fd[1]);
 +
 +	finish_connect(pid);
 +
 +	free(dest);
 +
 +	return refs;
 +}
 +
 +static int fetch_refs_via_pack(struct transport *transport,
 +			       int nr_heads, struct ref **to_fetch)
 +{
 +	struct git_transport_data *data = transport->data;
 +	char **heads = xmalloc(nr_heads * sizeof(*heads));
 +	char **origh = xmalloc(nr_heads * sizeof(*origh));
 +	struct ref *refs;
 +	char *dest = xstrdup(transport->url);
 +	struct fetch_pack_args args;
 +	int i;
 +
 +	memset(&args, 0, sizeof(args));
 +	args.uploadpack = data->uploadpack;
 +	args.keep_pack = data->keep;
 +	args.lock_pack = 1;
 +	args.use_thin_pack = data->thin;
 +	args.verbose = transport->verbose > 0;
 +	args.depth = data->depth;
 +
 +	for (i = 0; i < nr_heads; i++)
 +		origh[i] = heads[i] = xstrdup(to_fetch[i]->name);
 +	refs = fetch_pack(&args, dest, nr_heads, heads, &transport->pack_lockfile);
 +
 +	for (i = 0; i < nr_heads; i++)
 +		free(origh[i]);
 +	free(origh);
 +	free(heads);
 +	free_refs(refs);
 +	free(dest);
 +	return 0;
 +}
 +
 +static int git_transport_push(struct transport *transport, int refspec_nr, const char **refspec, int flags) {
 +	struct git_transport_data *data = transport->data;
 +	const char **argv;
 +	char *rem;
 +	int argc;
 +	int err;
 +
 +	argv = xmalloc((refspec_nr + 11) * sizeof(char *));
 +	argv[0] = "send-pack";
 +	argc = 1;
 +	if (flags & TRANSPORT_PUSH_ALL)
 +		argv[argc++] = "--all";
 +	if (flags & TRANSPORT_PUSH_FORCE)
 +		argv[argc++] = "--force";
++	if (flags & TRANSPORT_PUSH_DRY_RUN)
++		argv[argc++] = "--dry-run";
 +	if (data->receivepack) {
 +		char *rp = xmalloc(strlen(data->receivepack) + 16);
 +		sprintf(rp, "--receive-pack=%s", data->receivepack);
 +		argv[argc++] = rp;
 +	}
 +	if (data->thin)
 +		argv[argc++] = "--thin";
 +	rem = xmalloc(strlen(transport->remote->name) + 10);
 +	sprintf(rem, "--remote=%s", transport->remote->name);
 +	argv[argc++] = rem;
 +	argv[argc++] = transport->url;
 +	while (refspec_nr--)
 +		argv[argc++] = *refspec++;
 +	argv[argc] = NULL;
 +	err = run_command_v_opt(argv, RUN_GIT_CMD);
 +	switch (err) {
 +	case -ERR_RUN_COMMAND_FORK:
 +		error("unable to fork for %s", argv[0]);
 +	case -ERR_RUN_COMMAND_EXEC:
 +		error("unable to exec %s", argv[0]);
 +		break;
 +	case -ERR_RUN_COMMAND_WAITPID:
 +	case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
 +	case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
 +	case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
 +		error("%s died with strange error", argv[0]);
 +	}
 +	return !!err;
 +}
 +
 +static int disconnect_git(struct transport *transport)
 +{
 +	free(transport->data);
 +	return 0;
 +}
 +
 +static int is_local(const char *url)
 +{
 +	const char *colon = strchr(url, ':');
 +	const char *slash = strchr(url, '/');
 +	return !colon || (slash && slash < colon);
 +}
 +
 +static int is_file(const char *url)
 +{
 +	struct stat buf;
 +	if (stat(url, &buf))
 +		return 0;
 +	return S_ISREG(buf.st_mode);
 +}
 +
 +struct transport *transport_get(struct remote *remote, const char *url)
 +{
 +	struct transport *ret = xcalloc(1, sizeof(*ret));
 +
 +	ret->remote = remote;
 +	ret->url = url;
 +
 +	if (!prefixcmp(url, "rsync://")) {
 +		ret->get_refs_list = get_refs_via_rsync;
 +		ret->fetch = fetch_objs_via_rsync;
 +		ret->push = rsync_transport_push;
 +
 +	} else if (!prefixcmp(url, "http://")
 +	        || !prefixcmp(url, "https://")
 +	        || !prefixcmp(url, "ftp://")) {
 +#ifdef NO_CURL
 +		error("git was compiled without libcurl support.");
 +#else
 +		ret->get_refs_list = get_refs_via_curl;
 +		ret->fetch = fetch_objs_via_curl;
 +		ret->push = curl_transport_push;
 +#endif
 +		ret->disconnect = disconnect_walker;
 +
 +	} else if (is_local(url) && is_file(url)) {
 +		struct bundle_transport_data *data = xcalloc(1, sizeof(*data));
 +		ret->data = data;
 +		ret->get_refs_list = get_refs_from_bundle;
 +		ret->fetch = fetch_refs_from_bundle;
 +		ret->disconnect = close_bundle;
 +
 +	} else {
 +		struct git_transport_data *data = xcalloc(1, sizeof(*data));
 +		ret->data = data;
 +		ret->set_option = set_git_option;
 +		ret->get_refs_list = get_refs_via_connect;
 +		ret->fetch = fetch_refs_via_pack;
 +		ret->push = git_transport_push;
 +		ret->disconnect = disconnect_git;
 +
 +		data->thin = 1;
 +		data->uploadpack = "git-upload-pack";
 +		if (remote && remote->uploadpack)
 +			data->uploadpack = remote->uploadpack;
 +		data->receivepack = "git-receive-pack";
 +		if (remote && remote->receivepack)
 +			data->receivepack = remote->receivepack;
 +	}
 +
 +	return ret;
 +}
 +
 +int transport_set_option(struct transport *transport,
 +			 const char *name, const char *value)
 +{
 +	if (transport->set_option)
 +		return transport->set_option(transport, name, value);
 +	return 1;
 +}
 +
 +int transport_push(struct transport *transport,
 +		   int refspec_nr, const char **refspec, int flags)
 +{
 +	if (!transport->push)
 +		return 1;
 +	return transport->push(transport, refspec_nr, refspec, flags);
 +}
 +
 +struct ref *transport_get_remote_refs(struct transport *transport)
 +{
 +	if (!transport->remote_refs)
 +		transport->remote_refs = transport->get_refs_list(transport);
 +	return transport->remote_refs;
 +}
 +
 +int transport_fetch_refs(struct transport *transport, struct ref *refs)
 +{
 +	int rc;
 +	int nr_heads = 0, nr_alloc = 0;
 +	struct ref **heads = NULL;
 +	struct ref *rm;
 +
 +	for (rm = refs; rm; rm = rm->next) {
 +		if (rm->peer_ref &&
 +		    !hashcmp(rm->peer_ref->old_sha1, rm->old_sha1))
 +			continue;
 +		ALLOC_GROW(heads, nr_heads + 1, nr_alloc);
 +		heads[nr_heads++] = rm;
 +	}
 +
 +	rc = transport->fetch(transport, nr_heads, heads);
 +	free(heads);
 +	return rc;
 +}
 +
 +void transport_unlock_pack(struct transport *transport)
 +{
 +	if (transport->pack_lockfile) {
 +		unlink(transport->pack_lockfile);
 +		free(transport->pack_lockfile);
 +		transport->pack_lockfile = NULL;
 +	}
 +}
 +
 +int transport_disconnect(struct transport *transport)
 +{
 +	int ret = 0;
 +	if (transport->disconnect)
 +		ret = transport->disconnect(transport);
 +	free(transport);
 +	return ret;
 +}
diff --cc transport.h
index 4bb51d7b7,000000000..df12ea742
mode 100644,000000..100644
--- a/transport.h
+++ b/transport.h
@@@ -1,69 -1,0 +1,70 @@@
 +#ifndef TRANSPORT_H
 +#define TRANSPORT_H
 +
 +#include "cache.h"
 +#include "remote.h"
 +
 +struct transport {
 +	struct remote *remote;
 +	const char *url;
 +	void *data;
 +	struct ref *remote_refs;
 +
 +	/**
 +	 * Returns 0 if successful, positive if the option is not
 +	 * recognized or is inapplicable, and negative if the option
 +	 * is applicable but the value is invalid.
 +	 **/
 +	int (*set_option)(struct transport *connection, const char *name,
 +			  const char *value);
 +
 +	struct ref *(*get_refs_list)(const struct transport *transport);
 +	int (*fetch)(struct transport *transport, int refs_nr, struct ref **refs);
 +	int (*push)(struct transport *connection, int refspec_nr, const char **refspec, int flags);
 +
 +	int (*disconnect)(struct transport *connection);
 +	char *pack_lockfile;
 +	signed verbose : 2;
 +};
 +
 +#define TRANSPORT_PUSH_ALL 1
 +#define TRANSPORT_PUSH_FORCE 2
++#define TRANSPORT_PUSH_DRY_RUN 4
 +
 +/* Returns a transport suitable for the url */
 +struct transport *transport_get(struct remote *, const char *);
 +
 +/* Transport options which apply to git:// and scp-style URLs */
 +
 +/* The program to use on the remote side to send a pack */
 +#define TRANS_OPT_UPLOADPACK "uploadpack"
 +
 +/* The program to use on the remote side to receive a pack */
 +#define TRANS_OPT_RECEIVEPACK "receivepack"
 +
 +/* Transfer the data as a thin pack if not null */
 +#define TRANS_OPT_THIN "thin"
 +
 +/* Keep the pack that was transferred if not null */
 +#define TRANS_OPT_KEEP "keep"
 +
 +/* Limit the depth of the fetch if not null */
 +#define TRANS_OPT_DEPTH "depth"
 +
 +/**
 + * Returns 0 if the option was used, non-zero otherwise. Prints a
 + * message to stderr if the option is not used.
 + **/
 +int transport_set_option(struct transport *transport, const char *name,
 +			 const char *value);
 +
 +int transport_push(struct transport *connection,
 +		   int refspec_nr, const char **refspec, int flags);
 +
 +struct ref *transport_get_remote_refs(struct transport *transport);
 +
 +int transport_fetch_refs(struct transport *transport, struct ref *refs);
 +void transport_unlock_pack(struct transport *transport);
 +int transport_disconnect(struct transport *transport);
 +
 +#endif
diff --cc walker.c
index 5c65ea494,b1c1f07b2..397b80de9
--- a/walker.c
+++ b/walker.c
@@@ -6,13 -6,17 +6,12 @@@
  #include "tag.h"
  #include "blob.h"
  #include "refs.h"
- #include "strbuf.h"
  
 -int get_tree = 0;
 -int get_history = 0;
 -int get_all = 0;
 -int get_verbosely = 0;
 -int get_recover = 0;
  static unsigned char current_commit_sha1[20];
  
 -void pull_say(const char *fmt, const char *hex)
 +void walker_say(struct walker *walker, const char *fmt, const char *hex)
  {
 -	if (get_verbosely)
 +	if (walker->get_verbosely)
  		fprintf(stderr, fmt, hex);
  }