git/builtin-send-pack.c
Shawn O. Pearce de1a2fdd38 Smart push over HTTP: client side
The git-remote-curl backend detects if the remote server supports
the git-receive-pack service, and if so, runs git-send-pack in a
pipe to dump the command and pack data as a single POST request.

The advertisements from the server that were obtained during the
discovery are passed into git-send-pack before the POST request
starts.  This permits git-send-pack to operate largely unmodified.

For smaller packs (those under 1 MiB) a HTTP/1.0 POST with a
Content-Length is used, permitting interaction with any server.
The 1 MiB limit is arbitrary, but is sufficent to fit most deltas
created by human authors against text sources with the occasional
small binary file (e.g. few KiB icon image).  The configuration
option http.postBuffer can be used to increase (or shink) this
buffer if the default is not sufficient.

For larger packs which cannot be spooled entirely into the helper's
memory space (due to http.postBuffer being too small), the POST
request requires HTTP/1.1 and sets "Transfer-Encoding: chunked".
This permits the client to upload an unknown amount of data in one
HTTP transaction without needing to pregenerate the entire pack
file locally.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
CC: Daniel Barkalow <barkalow@iabervon.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-11-04 17:58:15 -08:00

700 lines
16 KiB
C

#include "cache.h"
#include "commit.h"
#include "refs.h"
#include "pkt-line.h"
#include "sideband.h"
#include "run-command.h"
#include "remote.h"
#include "send-pack.h"
#include "quote.h"
static const char send_pack_usage[] =
"git send-pack [--all | --mirror] [--dry-run] [--force] [--receive-pack=<git-receive-pack>] [--verbose] [--thin] [<host>:]<directory> [<ref>...]\n"
" --all and explicit <ref> specification are mutually exclusive.";
static struct send_pack_args args;
static int feed_object(const unsigned char *sha1, int fd, int negative)
{
char buf[42];
if (negative && !has_sha1_file(sha1))
return 1;
memcpy(buf + negative, sha1_to_hex(sha1), 40);
if (negative)
buf[0] = '^';
buf[40 + negative] = '\n';
return write_or_whine(fd, buf, 41 + negative, "send-pack: send refs");
}
/*
* Make a pack stream and spit it out into file descriptor fd
*/
static int pack_objects(int fd, struct ref *refs, struct extra_have_objects *extra, struct send_pack_args *args)
{
/*
* The child becomes pack-objects --revs; we feed
* the revision parameters to it via its stdin and
* let its stdout go back to the other end.
*/
const char *argv[] = {
"pack-objects",
"--all-progress",
"--revs",
"--stdout",
NULL,
NULL,
NULL,
NULL,
};
struct child_process po;
int i;
i = 4;
if (args->use_thin_pack)
argv[i++] = "--thin";
if (args->use_ofs_delta)
argv[i++] = "--delta-base-offset";
if (args->quiet)
argv[i++] = "-q";
memset(&po, 0, sizeof(po));
po.argv = argv;
po.in = -1;
po.out = args->stateless_rpc ? -1 : fd;
po.git_cmd = 1;
if (start_command(&po))
die_errno("git pack-objects failed");
/*
* We feed the pack-objects we just spawned with revision
* parameters by writing to the pipe.
*/
for (i = 0; i < extra->nr; i++)
if (!feed_object(extra->array[i], po.in, 1))
break;
while (refs) {
if (!is_null_sha1(refs->old_sha1) &&
!feed_object(refs->old_sha1, po.in, 1))
break;
if (!is_null_sha1(refs->new_sha1) &&
!feed_object(refs->new_sha1, po.in, 0))
break;
refs = refs->next;
}
close(po.in);
if (args->stateless_rpc) {
char *buf = xmalloc(LARGE_PACKET_MAX);
while (1) {
ssize_t n = xread(po.out, buf, LARGE_PACKET_MAX);
if (n <= 0)
break;
send_sideband(fd, -1, buf, n, LARGE_PACKET_MAX);
}
free(buf);
close(po.out);
po.out = -1;
}
if (finish_command(&po))
return error("pack-objects died with strange error");
return 0;
}
static int receive_status(int in, struct ref *refs)
{
struct ref *hint;
char line[1000];
int ret = 0;
int len = packet_read_line(in, line, sizeof(line));
if (len < 10 || memcmp(line, "unpack ", 7))
return error("did not receive remote status");
if (memcmp(line, "unpack ok\n", 10)) {
char *p = line + strlen(line) - 1;
if (*p == '\n')
*p = '\0';
error("unpack failed: %s", line + 7);
ret = -1;
}
hint = NULL;
while (1) {
char *refname;
char *msg;
len = packet_read_line(in, line, sizeof(line));
if (!len)
break;
if (len < 3 ||
(memcmp(line, "ok ", 3) && memcmp(line, "ng ", 3))) {
fprintf(stderr, "protocol error: %s\n", line);
ret = -1;
break;
}
line[strlen(line)-1] = '\0';
refname = line + 3;
msg = strchr(refname, ' ');
if (msg)
*msg++ = '\0';
/* first try searching at our hint, falling back to all refs */
if (hint)
hint = find_ref_by_name(hint, refname);
if (!hint)
hint = find_ref_by_name(refs, refname);
if (!hint) {
warning("remote reported status on unknown ref: %s",
refname);
continue;
}
if (hint->status != REF_STATUS_EXPECTING_REPORT) {
warning("remote reported status on unexpected ref: %s",
refname);
continue;
}
if (line[0] == 'o' && line[1] == 'k')
hint->status = REF_STATUS_OK;
else {
hint->status = REF_STATUS_REMOTE_REJECT;
ret = -1;
}
if (msg)
hint->remote_status = xstrdup(msg);
/* start our next search from the next ref */
hint = hint->next;
}
return ret;
}
static void update_tracking_ref(struct remote *remote, struct ref *ref)
{
struct refspec rs;
if (ref->status != REF_STATUS_OK && ref->status != REF_STATUS_UPTODATE)
return;
rs.src = ref->name;
rs.dst = NULL;
if (!remote_find_tracking(remote, &rs)) {
if (args.verbose)
fprintf(stderr, "updating local tracking ref '%s'\n", rs.dst);
if (ref->deletion) {
delete_ref(rs.dst, NULL, 0);
} else
update_ref("update by push", rs.dst,
ref->new_sha1, NULL, 0, 0);
free(rs.dst);
}
}
#define SUMMARY_WIDTH (2 * DEFAULT_ABBREV + 3)
static void print_ref_status(char flag, const char *summary, struct ref *to, struct ref *from, const char *msg)
{
fprintf(stderr, " %c %-*s ", flag, SUMMARY_WIDTH, summary);
if (from)
fprintf(stderr, "%s -> %s", prettify_refname(from->name), prettify_refname(to->name));
else
fputs(prettify_refname(to->name), stderr);
if (msg) {
fputs(" (", stderr);
fputs(msg, stderr);
fputc(')', stderr);
}
fputc('\n', stderr);
}
static const char *status_abbrev(unsigned char sha1[20])
{
return find_unique_abbrev(sha1, DEFAULT_ABBREV);
}
static void print_ok_ref_status(struct ref *ref)
{
if (ref->deletion)
print_ref_status('-', "[deleted]", ref, NULL, NULL);
else if (is_null_sha1(ref->old_sha1))
print_ref_status('*',
(!prefixcmp(ref->name, "refs/tags/") ? "[new tag]" :
"[new branch]"),
ref, ref->peer_ref, NULL);
else {
char quickref[84];
char type;
const char *msg;
strcpy(quickref, status_abbrev(ref->old_sha1));
if (ref->nonfastforward) {
strcat(quickref, "...");
type = '+';
msg = "forced update";
} else {
strcat(quickref, "..");
type = ' ';
msg = NULL;
}
strcat(quickref, status_abbrev(ref->new_sha1));
print_ref_status(type, quickref, ref, ref->peer_ref, msg);
}
}
static int print_one_push_status(struct ref *ref, const char *dest, int count)
{
if (!count)
fprintf(stderr, "To %s\n", dest);
switch(ref->status) {
case REF_STATUS_NONE:
print_ref_status('X', "[no match]", ref, NULL, NULL);
break;
case REF_STATUS_REJECT_NODELETE:
print_ref_status('!', "[rejected]", ref, NULL,
"remote does not support deleting refs");
break;
case REF_STATUS_UPTODATE:
print_ref_status('=', "[up to date]", ref,
ref->peer_ref, NULL);
break;
case REF_STATUS_REJECT_NONFASTFORWARD:
print_ref_status('!', "[rejected]", ref, ref->peer_ref,
"non-fast forward");
break;
case REF_STATUS_REMOTE_REJECT:
print_ref_status('!', "[remote rejected]", ref,
ref->deletion ? NULL : ref->peer_ref,
ref->remote_status);
break;
case REF_STATUS_EXPECTING_REPORT:
print_ref_status('!', "[remote failure]", ref,
ref->deletion ? NULL : ref->peer_ref,
"remote failed to report status");
break;
case REF_STATUS_OK:
print_ok_ref_status(ref);
break;
}
return 1;
}
static void print_push_status(const char *dest, struct ref *refs)
{
struct ref *ref;
int n = 0;
if (args.verbose) {
for (ref = refs; ref; ref = ref->next)
if (ref->status == REF_STATUS_UPTODATE)
n += print_one_push_status(ref, dest, n);
}
for (ref = refs; ref; ref = ref->next)
if (ref->status == REF_STATUS_OK)
n += print_one_push_status(ref, dest, n);
for (ref = refs; ref; ref = ref->next) {
if (ref->status != REF_STATUS_NONE &&
ref->status != REF_STATUS_UPTODATE &&
ref->status != REF_STATUS_OK)
n += print_one_push_status(ref, dest, n);
}
}
static int refs_pushed(struct ref *ref)
{
for (; ref; ref = ref->next) {
switch(ref->status) {
case REF_STATUS_NONE:
case REF_STATUS_UPTODATE:
break;
default:
return 1;
}
}
return 0;
}
static void print_helper_status(struct ref *ref)
{
struct strbuf buf = STRBUF_INIT;
for (; ref; ref = ref->next) {
const char *msg = NULL;
const char *res;
switch(ref->status) {
case REF_STATUS_NONE:
res = "error";
msg = "no match";
break;
case REF_STATUS_OK:
res = "ok";
break;
case REF_STATUS_UPTODATE:
res = "ok";
msg = "up to date";
break;
case REF_STATUS_REJECT_NONFASTFORWARD:
res = "error";
msg = "non-fast forward";
break;
case REF_STATUS_REJECT_NODELETE:
case REF_STATUS_REMOTE_REJECT:
res = "error";
break;
case REF_STATUS_EXPECTING_REPORT:
default:
continue;
}
strbuf_reset(&buf);
strbuf_addf(&buf, "%s %s", res, ref->name);
if (ref->remote_status)
msg = ref->remote_status;
if (msg) {
strbuf_addch(&buf, ' ');
quote_two_c_style(&buf, "", msg, 0);
}
strbuf_addch(&buf, '\n');
safe_write(1, buf.buf, buf.len);
}
strbuf_release(&buf);
}
int send_pack(struct send_pack_args *args,
int fd[], struct child_process *conn,
struct ref *remote_refs,
struct extra_have_objects *extra_have)
{
int in = fd[0];
int out = fd[1];
struct strbuf req_buf = STRBUF_INIT;
struct ref *ref;
int new_refs;
int ask_for_status_report = 0;
int allow_deleting_refs = 0;
int expect_status_report = 0;
int ret;
/* Does the other end support the reporting? */
if (server_supports("report-status"))
ask_for_status_report = 1;
if (server_supports("delete-refs"))
allow_deleting_refs = 1;
if (server_supports("ofs-delta"))
args->use_ofs_delta = 1;
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;
}
/*
* Finally, tell the other end!
*/
new_refs = 0;
for (ref = remote_refs; ref; ref = ref->next) {
if (ref->peer_ref)
hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
else if (!args->send_mirror)
continue;
ref->deletion = is_null_sha1(ref->new_sha1);
if (ref->deletion && !allow_deleting_refs) {
ref->status = REF_STATUS_REJECT_NODELETE;
continue;
}
if (!ref->deletion &&
!hashcmp(ref->old_sha1, ref->new_sha1)) {
ref->status = REF_STATUS_UPTODATE;
continue;
}
/* This part determines what can overwrite what.
* The rules are:
*
* (0) you can always use --force or +A:B notation to
* selectively force individual ref pairs.
*
* (1) if the old thing does not exist, it is OK.
*
* (2) if you do not have the old thing, you are not allowed
* to overwrite it; you would not know what you are losing
* otherwise.
*
* (3) if both new and old are commit-ish, and new is a
* descendant of old, it is OK.
*
* (4) regardless of all of the above, removing :B is
* always allowed.
*/
ref->nonfastforward =
!ref->deletion &&
!is_null_sha1(ref->old_sha1) &&
(!has_sha1_file(ref->old_sha1)
|| !ref_newer(ref->new_sha1, ref->old_sha1));
if (ref->nonfastforward && !ref->force && !args->force_update) {
ref->status = REF_STATUS_REJECT_NONFASTFORWARD;
continue;
}
if (!ref->deletion)
new_refs++;
if (!args->dry_run) {
char *old_hex = sha1_to_hex(ref->old_sha1);
char *new_hex = sha1_to_hex(ref->new_sha1);
if (ask_for_status_report) {
packet_buf_write(&req_buf, "%s %s %s%c%s",
old_hex, new_hex, ref->name, 0,
"report-status");
ask_for_status_report = 0;
expect_status_report = 1;
}
else
packet_buf_write(&req_buf, "%s %s %s",
old_hex, new_hex, ref->name);
}
ref->status = expect_status_report ?
REF_STATUS_EXPECTING_REPORT :
REF_STATUS_OK;
}
if (args->stateless_rpc) {
if (!args->dry_run) {
packet_buf_flush(&req_buf);
send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);
}
} else {
safe_write(out, req_buf.buf, req_buf.len);
packet_flush(out);
}
strbuf_release(&req_buf);
if (new_refs && !args->dry_run) {
if (pack_objects(out, remote_refs, extra_have, args) < 0) {
for (ref = remote_refs; ref; ref = ref->next)
ref->status = REF_STATUS_NONE;
return -1;
}
}
if (args->stateless_rpc && !args->dry_run)
packet_flush(out);
if (expect_status_report)
ret = receive_status(in, remote_refs);
else
ret = 0;
if (args->stateless_rpc)
packet_flush(out);
if (ret < 0)
return ret;
for (ref = remote_refs; ref; ref = ref->next) {
switch (ref->status) {
case REF_STATUS_NONE:
case REF_STATUS_UPTODATE:
case REF_STATUS_OK:
break;
default:
return -1;
}
}
return 0;
}
static void verify_remote_names(int nr_heads, const char **heads)
{
int i;
for (i = 0; i < nr_heads; i++) {
const char *local = heads[i];
const char *remote = strrchr(heads[i], ':');
if (*local == '+')
local++;
/* A matching refspec is okay. */
if (remote == local && remote[1] == '\0')
continue;
remote = remote ? (remote + 1) : local;
switch (check_ref_format(remote)) {
case 0: /* ok */
case CHECK_REF_FORMAT_ONELEVEL:
/* ok but a single level -- that is fine for
* a match pattern.
*/
case CHECK_REF_FORMAT_WILDCARD:
/* ok but ends with a pattern-match character */
continue;
}
die("remote part of refspec is not a valid name in %s",
heads[i]);
}
}
int cmd_send_pack(int argc, const char **argv, const char *prefix)
{
int i, nr_refspecs = 0;
const char **refspecs = NULL;
const char *remote_name = NULL;
struct remote *remote = NULL;
const char *dest = NULL;
int fd[2];
struct child_process *conn;
struct extra_have_objects extra_have;
struct ref *remote_refs, *local_refs;
int ret;
int helper_status = 0;
int send_all = 0;
const char *receivepack = "git-receive-pack";
int flags;
argv++;
for (i = 1; i < argc; i++, argv++) {
const char *arg = *argv;
if (*arg == '-') {
if (!prefixcmp(arg, "--receive-pack=")) {
receivepack = arg + 15;
continue;
}
if (!prefixcmp(arg, "--exec=")) {
receivepack = arg + 7;
continue;
}
if (!prefixcmp(arg, "--remote=")) {
remote_name = arg + 9;
continue;
}
if (!strcmp(arg, "--all")) {
send_all = 1;
continue;
}
if (!strcmp(arg, "--dry-run")) {
args.dry_run = 1;
continue;
}
if (!strcmp(arg, "--mirror")) {
args.send_mirror = 1;
continue;
}
if (!strcmp(arg, "--force")) {
args.force_update = 1;
continue;
}
if (!strcmp(arg, "--verbose")) {
args.verbose = 1;
continue;
}
if (!strcmp(arg, "--thin")) {
args.use_thin_pack = 1;
continue;
}
if (!strcmp(arg, "--stateless-rpc")) {
args.stateless_rpc = 1;
continue;
}
if (!strcmp(arg, "--helper-status")) {
helper_status = 1;
continue;
}
usage(send_pack_usage);
}
if (!dest) {
dest = arg;
continue;
}
refspecs = (const char **) argv;
nr_refspecs = argc - i;
break;
}
if (!dest)
usage(send_pack_usage);
/*
* --all and --mirror are incompatible; neither makes sense
* with any refspecs.
*/
if ((refspecs && (send_all || args.send_mirror)) ||
(send_all && args.send_mirror))
usage(send_pack_usage);
if (remote_name) {
remote = remote_get(remote_name);
if (!remote_has_url(remote, dest)) {
die("Destination %s is not a uri for %s",
dest, remote_name);
}
}
if (args.stateless_rpc) {
conn = NULL;
fd[0] = 0;
fd[1] = 1;
} else {
conn = git_connect(fd, dest, receivepack,
args.verbose ? CONNECT_VERBOSE : 0);
}
memset(&extra_have, 0, sizeof(extra_have));
get_remote_heads(fd[0], &remote_refs, 0, NULL, REF_NORMAL,
&extra_have);
verify_remote_names(nr_refspecs, refspecs);
local_refs = get_local_heads();
flags = MATCH_REFS_NONE;
if (send_all)
flags |= MATCH_REFS_ALL;
if (args.send_mirror)
flags |= MATCH_REFS_MIRROR;
/* match them up */
if (match_refs(local_refs, &remote_refs, nr_refspecs, refspecs, flags))
return -1;
ret = send_pack(&args, fd, conn, remote_refs, &extra_have);
if (helper_status)
print_helper_status(remote_refs);
close(fd[1]);
close(fd[0]);
ret |= finish_connect(conn);
if (!helper_status)
print_push_status(dest, remote_refs);
if (!args.dry_run && remote) {
struct ref *ref;
for (ref = remote_refs; ref; ref = ref->next)
update_tracking_ref(remote, ref);
}
if (!ret && !refs_pushed(remote_refs))
fprintf(stderr, "Everything up-to-date\n");
return ret;
}