#include "cache.h"

#include "refs.h"

#include "pkt-line.h"

#include "sideband.h"

#include "tag.h"

#include "object.h"

#include "commit.h"

#include "exec_cmd.h"

#include "diff.h"

#include "revision.h"

#include "list-objects.h"

#include "run-command.h"

#include "connect.h"

#include "sigchain.h"

#include "version.h"

#include "string-list.h"

static const char upload_pack_usage[] = "git upload-pack [--strict] [--timeout=<n>] <dir>";

/* bits #0..7 in revision.h, #8..10 in commit.c */

#define THEY_HAVE (1u << 11)

#define OUR_REF (1u << 12)

#define WANTED (1u << 13)

#define COMMON_KNOWN (1u << 14)

#define REACHABLE (1u << 15)

#define SHALLOW (1u << 16)

#define NOT_SHALLOW (1u << 17)

#define CLIENT_SHALLOW (1u << 18)

#define HIDDEN_REF (1u << 19)

static unsigned long oldest_have;

static int multi_ack;

static int no_done;

static int use_thin_pack, use_ofs_delta, use_include_tag;

static int no_progress, daemon_mode;

static int allow_tip_sha1_in_want;

static int shallow_nr;

static struct object_array have_obj;

static struct object_array want_obj;

static struct object_array extra_edge_obj;

static unsigned int timeout;

static int keepalive = 5;

/* 0 for no sideband,

* otherwise maximum packet size (up to 65520 bytes).

*/

static int use_sideband;

static int advertise_refs;

static int stateless_rpc;

static void reset_timeout(void)

{

alarm(timeout);

}

static ssize_t send_client_data(int fd, const char *data, ssize_t sz)

{

if (use_sideband)

return send_sideband(1, fd, data, sz, use_sideband);

if (fd == 3)

/* emergency quit */

fd = 2;

if (fd == 2) {

/* XXX: are we happy to lose stuff here? */

xwrite(fd, data, sz);

return sz;

}

write_or_die(fd, data, sz);

return sz;

}

static void create_pack_file(void)

{

struct child_process pack_objects;

char data[8193], progress[128];

char abort_msg[] = "aborting due to possible repository "

"corruption on the remote side.";

int buffered = -1;

ssize_t sz;

const char *argv[12];

int i, arg = 0;

FILE *pipe_fd;

const char *shallow_file = NULL;

if (shallow_nr) {

shallow_file = setup_temporary_shallow(NULL);

argv[arg++] = "--shallow-file";

argv[arg++] = shallow_file;

}

argv[arg++] = "pack-objects";

argv[arg++] = "--revs";

if (use_thin_pack)

argv[arg++] = "--thin";

argv[arg++] = "--stdout";

if (!no_progress)

argv[arg++] = "--progress";

if (use_ofs_delta)

argv[arg++] = "--delta-base-offset";

if (use_include_tag)

argv[arg++] = "--include-tag";

argv[arg++] = NULL;

memset(&pack_objects, 0, sizeof(pack_objects));

pack_objects.in = -1;

pack_objects.out = -1;

pack_objects.err = -1;

pack_objects.git_cmd = 1;

pack_objects.argv = argv;

if (start_command(&pack_objects))

die("git upload-pack: unable to fork git-pack-objects");

pipe_fd = xfdopen(pack_objects.in, "w");

for (i = 0; i < want_obj.nr; i++)

fprintf(pipe_fd, "%s\n",

sha1_to_hex(want_obj.objects[i].item->sha1));

fprintf(pipe_fd, "--not\n");

for (i = 0; i < have_obj.nr; i++)

fprintf(pipe_fd, "%s\n",

sha1_to_hex(have_obj.objects[i].item->sha1));

for (i = 0; i < extra_edge_obj.nr; i++)

fprintf(pipe_fd, "%s\n",

sha1_to_hex(extra_edge_obj.objects[i].item->sha1));

fprintf(pipe_fd, "\n");

fflush(pipe_fd);

fclose(pipe_fd);

/* We read from pack_objects.err to capture stderr output for

* progress bar, and pack_objects.out to capture the pack data.

*/

while (1) {

struct pollfd pfd[2];

int pe, pu, pollsize;

int ret;

reset_timeout();

pollsize = 0;

pe = pu = -1;

if (0 <= pack_objects.out) {

pfd[pollsize].fd = pack_objects.out;

pfd[pollsize].events = POLLIN;

pu = pollsize;

pollsize++;

}

if (0 <= pack_objects.err) {

pfd[pollsize].fd = pack_objects.err;

pfd[pollsize].events = POLLIN;

pe = pollsize;

pollsize++;

}

if (!pollsize)

break;

ret = poll(pfd, pollsize, 1000 * keepalive);

if (ret < 0) {

if (errno != EINTR) {

error("poll failed, resuming: %s",

strerror(errno));

sleep(1);

}

continue;

}

if (0 <= pe && (pfd[pe].revents & (POLLIN|POLLHUP))) {

/* Status ready; we ship that in the side-band

* or dump to the standard error.

*/

sz = xread(pack_objects.err, progress,

sizeof(progress));

if (0 < sz)

send_client_data(2, progress, sz);

else if (sz == 0) {

close(pack_objects.err);

pack_objects.err = -1;

}

else

goto fail;

/* give priority to status messages */

continue;

}

if (0 <= pu && (pfd[pu].revents & (POLLIN|POLLHUP))) {

/* Data ready; we keep the last byte to ourselves

* in case we detect broken rev-list, so that we

* can leave the stream corrupted. This is

* unfortunate -- unpack-objects would happily

* accept a valid packdata with trailing garbage,

* so appending garbage after we pass all the

* pack data is not good enough to signal

* breakage to downstream.

*/

char *cp = data;

ssize_t outsz = 0;

if (0 <= buffered) {

*cp++ = buffered;

outsz++;

}

sz = xread(pack_objects.out, cp,

sizeof(data) - outsz);

if (0 < sz)

;

else if (sz == 0) {

close(pack_objects.out);

pack_objects.out = -1;

}

else

goto fail;

sz += outsz;

if (1 < sz) {

buffered = data[sz-1] & 0xFF;

sz--;

}

else

buffered = -1;

sz = send_client_data(1, data, sz);

if (sz < 0)

goto fail;

}

/*

* We hit the keepalive timeout without saying anything; send

* an empty message on the data sideband just to let the other

* side know we're still working on it, but don't have any data

* yet.

*

* If we don't have a sideband channel, there's no room in the

* protocol to say anything, so those clients are just out of

* luck.

*/

if (!ret && use_sideband) {

static const char buf[] = "0005\1";

write_or_die(1, buf, 5);

}

}

if (finish_command(&pack_objects)) {

error("git upload-pack: git-pack-objects died with error.");

goto fail;

}

/* flush the data */

if (0 <= buffered) {

data[0] = buffered;

sz = send_client_data(1, data, 1);

if (sz < 0)

goto fail;

fprintf(stderr, "flushed.\n");

}

if (use_sideband)

packet_flush(1);

return;

fail:

send_client_data(3, abort_msg, sizeof(abort_msg));

die("git upload-pack: %s", abort_msg);

}

static int got_sha1(char *hex, unsigned char *sha1)

{

struct object *o;

int we_knew_they_have = 0;

if (get_sha1_hex(hex, sha1))

die("git upload-pack: expected SHA1 object, got '%s'", hex);

if (!has_sha1_file(sha1))

return -1;

o = parse_object(sha1);

if (!o)

die("oops (%s)", sha1_to_hex(sha1));

if (o->type == OBJ_COMMIT) {

struct commit_list *parents;

struct commit *commit = (struct commit *)o;

if (o->flags & THEY_HAVE)

we_knew_they_have = 1;

else

o->flags |= THEY_HAVE;

if (!oldest_have || (commit->date < oldest_have))

oldest_have = commit->date;

for (parents = commit->parents;

parents;

parents = parents->next)

parents->item->object.flags |= THEY_HAVE;

}

if (!we_knew_they_have) {

add_object_array(o, NULL, &have_obj);

return 1;

}

return 0;

}

static int reachable(struct commit *want)

{

struct commit_list *work = NULL;

commit_list_insert_by_date(want, &work);

while (work) {

struct commit_list *list = work->next;

struct commit *commit = work->item;

free(work);

work = list;

if (commit->object.flags & THEY_HAVE) {

want->object.flags |= COMMON_KNOWN;

break;

}

if (!commit->object.parsed)

parse_object(commit->object.sha1);

if (commit->object.flags & REACHABLE)

continue;

commit->object.flags |= REACHABLE;

if (commit->date < oldest_have)

continue;

for (list = commit->parents; list; list = list->next) {

struct commit *parent = list->item;

if (!(parent->object.flags & REACHABLE))

commit_list_insert_by_date(parent, &work);

}

}

want->object.flags |= REACHABLE;

clear_commit_marks(want, REACHABLE);

free_commit_list(work);

return (want->object.flags & COMMON_KNOWN);

}

static int ok_to_give_up(void)

{

int i;

if (!have_obj.nr)

return 0;

for (i = 0; i < want_obj.nr; i++) {

struct object *want = want_obj.objects[i].item;

if (want->flags & COMMON_KNOWN)

continue;

want = deref_tag(want, "a want line", 0);

if (!want || want->type != OBJ_COMMIT) {

/* no way to tell if this is reachable by

* looking at the ancestry chain alone, so

* leave a note to ourselves not to worry about

* this object anymore.

*/

want_obj.objects[i].item->flags |= COMMON_KNOWN;

continue;

}

if (!reachable((struct commit *)want))

return 0;

}

return 1;

}

static int get_common_commits(void)

{

unsigned char sha1[20];

char last_hex[41];

int got_common = 0;

int got_other = 0;

int sent_ready = 0;

save_commit_buffer = 0;

for (;;) {

char *line = packet_read_line(0, NULL);

reset_timeout();

if (!line) {

if (multi_ack == 2 && got_common

&& !got_other && ok_to_give_up()) {

sent_ready = 1;

packet_write(1, "ACK %s ready\n", last_hex);

}

if (have_obj.nr == 0 || multi_ack)

packet_write(1, "NAK\n");

if (no_done && sent_ready) {

packet_write(1, "ACK %s\n", last_hex);

return 0;

}

if (stateless_rpc)

exit(0);

got_common = 0;

got_other = 0;

continue;

}

if (starts_with(line, "have ")) {

switch (got_sha1(line+5, sha1)) {

case -1: /* they have what we do not */

got_other = 1;

if (multi_ack && ok_to_give_up()) {

const char *hex = sha1_to_hex(sha1);

if (multi_ack == 2) {

sent_ready = 1;

packet_write(1, "ACK %s ready\n", hex);

} else

packet_write(1, "ACK %s continue\n", hex);

}

break;

default:

got_common = 1;

memcpy(last_hex, sha1_to_hex(sha1), 41);

if (multi_ack == 2)

packet_write(1, "ACK %s common\n", last_hex);

else if (multi_ack)

packet_write(1, "ACK %s continue\n", last_hex);

else if (have_obj.nr == 1)

packet_write(1, "ACK %s\n", last_hex);

break;

}

continue;

}

if (!strcmp(line, "done")) {

if (have_obj.nr > 0) {

if (multi_ack)

packet_write(1, "ACK %s\n", last_hex);

return 0;

}

packet_write(1, "NAK\n");

return -1;

}

die("git upload-pack: expected SHA1 list, got '%s'", line);

}

}

static int is_our_ref(struct object *o)

{

return o->flags &

((allow_tip_sha1_in_want ? HIDDEN_REF : 0) | OUR_REF);

}

static void check_non_tip(void)

{

static const char *argv[] = {

"rev-list", "--stdin", NULL,

};

static struct child_process cmd;

struct object *o;

char namebuf[42]; /* ^ + SHA-1 + LF */

int i;

/* In the normal in-process case non-tip request can never happen */

if (!stateless_rpc)

goto error;

cmd.argv = argv;

cmd.git_cmd = 1;

cmd.no_stderr = 1;

cmd.in = -1;

cmd.out = -1;

if (start_command(&cmd))

goto error;

/*

* If rev-list --stdin encounters an unknown commit, it

* terminates, which will cause SIGPIPE in the write loop

* below.

*/

sigchain_push(SIGPIPE, SIG_IGN);

namebuf[0] = '^';

namebuf[41] = '\n';

for (i = get_max_object_index(); 0 < i; ) {

o = get_indexed_object(--i);

if (!o)

continue;

if (!is_our_ref(o))

continue;

memcpy(namebuf + 1, sha1_to_hex(o->sha1), 40);

if (write_in_full(cmd.in, namebuf, 42) < 0)

goto error;

}

namebuf[40] = '\n';

for (i = 0; i < want_obj.nr; i++) {

o = want_obj.objects[i].item;

if (is_our_ref(o))

continue;

memcpy(namebuf, sha1_to_hex(o->sha1), 40);

if (write_in_full(cmd.in, namebuf, 41) < 0)

goto error;

}

close(cmd.in);

sigchain_pop(SIGPIPE);

/*

* The commits out of the rev-list are not ancestors of

* our ref.

*/

i = read_in_full(cmd.out, namebuf, 1);

if (i)

goto error;

close(cmd.out);

/*

* rev-list may have died by encountering a bad commit

* in the history, in which case we do want to bail out

* even when it showed no commit.

*/

if (finish_command(&cmd))

goto error;

/* All the non-tip ones are ancestors of what we advertised */

return;

error:

/* Pick one of them (we know there at least is one) */

for (i = 0; i < want_obj.nr; i++) {

o = want_obj.objects[i].item;

if (!is_our_ref(o))

die("git upload-pack: not our ref %s",

sha1_to_hex(o->sha1));

}

}

static void receive_needs(void)

{

struct object_array shallows = OBJECT_ARRAY_INIT;

int depth = 0;

int has_non_tip = 0;

shallow_nr = 0;

for (;;) {

struct object *o;

const char *features;

unsigned char sha1_buf[20];

char *line = packet_read_line(0, NULL);

reset_timeout();

if (!line)

break;

if (starts_with(line, "shallow ")) {

unsigned char sha1[20];

struct object *object;

if (get_sha1_hex(line + 8, sha1))

die("invalid shallow line: %s", line);

object = parse_object(sha1);

if (!object)

continue;

if (object->type != OBJ_COMMIT)

die("invalid shallow object %s", sha1_to_hex(sha1));

if (!(object->flags & CLIENT_SHALLOW)) {

object->flags |= CLIENT_SHALLOW;

add_object_array(object, NULL, &shallows);

}

continue;

}

if (starts_with(line, "deepen ")) {

char *end;

depth = strtol(line + 7, &end, 0);

if (end == line + 7 || depth <= 0)

die("Invalid deepen: %s", line);

continue;

}

if (!starts_with(line, "want ") ||

get_sha1_hex(line+5, sha1_buf))

die("git upload-pack: protocol error, "

"expected to get sha, not '%s'", line);

features = line + 45;

if (parse_feature_request(features, "multi_ack_detailed"))

multi_ack = 2;

else if (parse_feature_request(features, "multi_ack"))

multi_ack = 1;

if (parse_feature_request(features, "no-done"))

no_done = 1;

if (parse_feature_request(features, "thin-pack"))

use_thin_pack = 1;

if (parse_feature_request(features, "ofs-delta"))

use_ofs_delta = 1;

if (parse_feature_request(features, "side-band-64k"))

use_sideband = LARGE_PACKET_MAX;

else if (parse_feature_request(features, "side-band"))

use_sideband = DEFAULT_PACKET_MAX;

if (parse_feature_request(features, "no-progress"))

no_progress = 1;

if (parse_feature_request(features, "include-tag"))

use_include_tag = 1;

o = parse_object(sha1_buf);

if (!o)

die("git upload-pack: not our ref %s",

sha1_to_hex(sha1_buf));

if (!(o->flags & WANTED)) {

o->flags |= WANTED;

if (!is_our_ref(o))

has_non_tip = 1;

add_object_array(o, NULL, &want_obj);

}

}

/*

* We have sent all our refs already, and the other end

* should have chosen out of them. When we are operating

* in the stateless RPC mode, however, their choice may

* have been based on the set of older refs advertised

* by another process that handled the initial request.

*/

if (has_non_tip)

check_non_tip();

if (!use_sideband && daemon_mode)

no_progress = 1;

if (depth == 0 && shallows.nr == 0)

return;

if (depth > 0) {

struct commit_list *result = NULL, *backup = NULL;

int i;

if (depth == INFINITE_DEPTH && !is_repository_shallow())

for (i = 0; i < shallows.nr; i++) {

struct object *object = shallows.objects[i].item;

object->flags |= NOT_SHALLOW;

}

else

backup = result =

get_shallow_commits(&want_obj, depth,

SHALLOW, NOT_SHALLOW);

while (result) {

struct object *object = &result->item->object;

if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) {

packet_write(1, "shallow %s",

sha1_to_hex(object->sha1));

register_shallow(object->sha1);

shallow_nr++;

}

result = result->next;

}

free_commit_list(backup);

for (i = 0; i < shallows.nr; i++) {

struct object *object = shallows.objects[i].item;

if (object->flags & NOT_SHALLOW) {

struct commit_list *parents;

packet_write(1, "unshallow %s",

sha1_to_hex(object->sha1));

object->flags &= ~CLIENT_SHALLOW;

/* make sure the real parents are parsed */

unregister_shallow(object->sha1);

object->parsed = 0;

parse_commit_or_die((struct commit *)object);

parents = ((struct commit *)object)->parents;

while (parents) {

add_object_array(&parents->item->object,

NULL, &want_obj);

parents = parents->next;

}

add_object_array(object, NULL, &extra_edge_obj);

}

/* make sure commit traversal conforms to client */

register_shallow(object->sha1);

}

packet_flush(1);

} else

if (shallows.nr > 0) {

int i;

for (i = 0; i < shallows.nr; i++)

register_shallow(shallows.objects[i].item->sha1);

}

shallow_nr += shallows.nr;

free(shallows.objects);

}

/* return non-zero if the ref is hidden, otherwise 0 */

static int mark_our_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)

{

struct object *o = lookup_unknown_object(sha1);

if (ref_is_hidden(refname)) {

o->flags |= HIDDEN_REF;

return 1;

}

if (!o)

die("git upload-pack: cannot find object %s:", sha1_to_hex(sha1));

o->flags |= OUR_REF;

return 0;

}

static void format_symref_info(struct strbuf *buf, struct string_list *symref)

{

struct string_list_item *item;

if (!symref->nr)

return;

for_each_string_list_item(item, symref)

strbuf_addf(buf, " symref=%s:%s", item->string, (char *)item->util);

}

static int send_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)

{

static const char *capabilities = "multi_ack thin-pack side-band"

" side-band-64k ofs-delta shallow no-progress"

" include-tag multi_ack_detailed";

const char *refname_nons = strip_namespace(refname);

unsigned char peeled[20];

if (mark_our_ref(refname, sha1, flag, NULL))

return 0;

if (capabilities) {

struct strbuf symref_info = STRBUF_INIT;

format_symref_info(&symref_info, cb_data);

packet_write(1, "%s %s%c%s%s%s%s agent=%s\n",

sha1_to_hex(sha1), refname_nons,

0, capabilities,

allow_tip_sha1_in_want ? " allow-tip-sha1-in-want" : "",

stateless_rpc ? " no-done" : "",

symref_info.buf,

git_user_agent_sanitized());

strbuf_release(&symref_info);

} else {

packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname_nons);

}

capabilities = NULL;

if (!peel_ref(refname, peeled))

packet_write(1, "%s %s^{}\n", sha1_to_hex(peeled), refname_nons);

return 0;

}

static int find_symref(const char *refname, const unsigned char *sha1, int flag,

void *cb_data)

{

const char *symref_target;

struct string_list_item *item;

unsigned char unused[20];

if ((flag & REF_ISSYMREF) == 0)

return 0;

symref_target = resolve_ref_unsafe(refname, unused, 0, &flag);

if (!symref_target || (flag & REF_ISSYMREF) == 0)

die("'%s' is a symref but it is not?", refname);

item = string_list_append(cb_data, refname);

item->util = xstrdup(symref_target);

return 0;

}

static void upload_pack(void)

{

struct string_list symref = STRING_LIST_INIT_DUP;

head_ref_namespaced(find_symref, &symref);

if (advertise_refs || !stateless_rpc) {

reset_timeout();

head_ref_namespaced(send_ref, &symref);

for_each_namespaced_ref(send_ref, &symref);

advertise_shallow_grafts(1);

packet_flush(1);

} else {

head_ref_namespaced(mark_our_ref, NULL);

for_each_namespaced_ref(mark_our_ref, NULL);

}

string_list_clear(&symref, 1);

if (advertise_refs)

return;

receive_needs();

if (want_obj.nr) {

get_common_commits();

create_pack_file();

}

}

static int upload_pack_config(const char *var, const char *value, void *unused)

{

if (!strcmp("uploadpack.allowtipsha1inwant", var))

allow_tip_sha1_in_want = git_config_bool(var, value);

else if (!strcmp("uploadpack.keepalive", var)) {

keepalive = git_config_int(var, value);

if (!keepalive)

keepalive = -1;

}

return parse_hide_refs_config(var, value, "uploadpack");

}

int main(int argc, char **argv)

{

char *dir;

int i;

int strict = 0;

git_setup_gettext();

packet_trace_identity("upload-pack");

git_extract_argv0_path(argv[0]);

read_replace_refs = 0;

for (i = 1; i < argc; i++) {

char *arg = argv[i];

if (arg[0] != '-')

break;

if (!strcmp(arg, "--advertise-refs")) {

advertise_refs = 1;

continue;

}

if (!strcmp(arg, "--stateless-rpc")) {

stateless_rpc = 1;

continue;

}

if (!strcmp(arg, "--strict")) {

strict = 1;

continue;

}

if (starts_with(arg, "--timeout=")) {

timeout = atoi(arg+10);

daemon_mode = 1;

continue;

}

if (!strcmp(arg, "--")) {

i++;

break;

}

}

if (i != argc-1)

usage(upload_pack_usage);

setup_path();

dir = argv[i];

if (!enter_repo(dir, strict))

die("'%s' does not appear to be a git repository", dir);

git_config(upload_pack_config, NULL);

upload_pack();

return 0;

}