git/transport-helper.c
Ilari Liusvaara b236752a87 Support remote archive from all smart transports
Previously, remote archive required internal (non remote-helper)
smart transport. Extend the remote archive to also support smart
transports implemented by remote helpers.

Signed-off-by: Ilari Liusvaara <ilari.liusvaara@elisanet.fi>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-12-28 00:24:15 -08:00

736 lines
17 KiB
C

#include "cache.h"
#include "transport.h"
#include "quote.h"
#include "run-command.h"
#include "commit.h"
#include "diff.h"
#include "revision.h"
#include "quote.h"
#include "remote.h"
static int debug;
struct helper_data
{
const char *name;
struct child_process *helper;
FILE *out;
unsigned fetch : 1,
import : 1,
option : 1,
push : 1,
connect : 1,
no_disconnect_req : 1;
/* These go from remote name (as in "list") to private name */
struct refspec *refspecs;
int refspec_nr;
/* Transport options for fetch-pack/send-pack (should one of
* those be invoked).
*/
struct git_transport_options transport_options;
};
static void sendline(struct helper_data *helper, struct strbuf *buffer)
{
if (debug)
fprintf(stderr, "Debug: Remote helper: -> %s", buffer->buf);
if (write_in_full(helper->helper->in, buffer->buf, buffer->len)
!= buffer->len)
die_errno("Full write to remote helper failed");
}
static int recvline_fh(FILE *helper, struct strbuf *buffer)
{
strbuf_reset(buffer);
if (debug)
fprintf(stderr, "Debug: Remote helper: Waiting...\n");
if (strbuf_getline(buffer, helper, '\n') == EOF) {
if (debug)
fprintf(stderr, "Debug: Remote helper quit.\n");
exit(128);
}
if (debug)
fprintf(stderr, "Debug: Remote helper: <- %s\n", buffer->buf);
return 0;
}
static int recvline(struct helper_data *helper, struct strbuf *buffer)
{
return recvline_fh(helper->out, buffer);
}
static void xchgline(struct helper_data *helper, struct strbuf *buffer)
{
sendline(helper, buffer);
recvline(helper, buffer);
}
static void write_constant(int fd, const char *str)
{
if (debug)
fprintf(stderr, "Debug: Remote helper: -> %s", str);
if (write_in_full(fd, str, strlen(str)) != strlen(str))
die_errno("Full write to remote helper failed");
}
const char *remove_ext_force(const char *url)
{
if (url) {
const char *colon = strchr(url, ':');
if (colon && colon[1] == ':')
return colon + 2;
}
return url;
}
static void do_take_over(struct transport *transport)
{
struct helper_data *data;
data = (struct helper_data *)transport->data;
transport_take_over(transport, data->helper);
fclose(data->out);
free(data);
}
static struct child_process *get_helper(struct transport *transport)
{
struct helper_data *data = transport->data;
struct strbuf buf = STRBUF_INIT;
struct child_process *helper;
const char **refspecs = NULL;
int refspec_nr = 0;
int refspec_alloc = 0;
int duped;
if (data->helper)
return data->helper;
helper = xcalloc(1, sizeof(*helper));
helper->in = -1;
helper->out = -1;
helper->err = 0;
helper->argv = xcalloc(4, sizeof(*helper->argv));
strbuf_addf(&buf, "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]);
data->helper = helper;
data->no_disconnect_req = 0;
/*
* Open the output as FILE* so strbuf_getline() can be used.
* Do this with duped fd because fclose() will close the fd,
* and stuff like taking over will require the fd to remain.
*/
duped = dup(helper->out);
if (duped < 0)
die_errno("Can't dup helper output fd");
data->out = xfdopen(duped, "r");
write_constant(helper->in, "capabilities\n");
while (1) {
const char *capname;
int mandatory = 0;
recvline(data, &buf);
if (!*buf.buf)
break;
if (*buf.buf == '*') {
capname = buf.buf + 1;
mandatory = 1;
} else
capname = buf.buf;
if (debug)
fprintf(stderr, "Debug: Got cap %s\n", capname);
if (!strcmp(capname, "fetch"))
data->fetch = 1;
else if (!strcmp(capname, "option"))
data->option = 1;
else if (!strcmp(capname, "push"))
data->push = 1;
else if (!strcmp(capname, "import"))
data->import = 1;
else if (!data->refspecs && !prefixcmp(capname, "refspec ")) {
ALLOC_GROW(refspecs,
refspec_nr + 1,
refspec_alloc);
refspecs[refspec_nr++] = strdup(buf.buf + strlen("refspec "));
} else if (!strcmp(capname, "connect")) {
data->connect = 1;
} else if (mandatory) {
die("Unknown madatory capability %s. This remote "
"helper probably needs newer version of Git.\n",
capname);
}
}
if (refspecs) {
int i;
data->refspec_nr = refspec_nr;
data->refspecs = parse_fetch_refspec(refspec_nr, refspecs);
for (i = 0; i < refspec_nr; i++) {
free((char *)refspecs[i]);
}
free(refspecs);
}
strbuf_release(&buf);
if (debug)
fprintf(stderr, "Debug: Capabilities complete.\n");
return data->helper;
}
static int disconnect_helper(struct transport *transport)
{
struct helper_data *data = transport->data;
struct strbuf buf = STRBUF_INIT;
if (data->helper) {
if (debug)
fprintf(stderr, "Debug: Disconnecting.\n");
if (!data->no_disconnect_req) {
strbuf_addf(&buf, "\n");
sendline(data, &buf);
}
close(data->helper->in);
close(data->helper->out);
fclose(data->out);
finish_command(data->helper);
free((char *)data->helper->argv[0]);
free(data->helper->argv);
free(data->helper);
data->helper = NULL;
}
return 0;
}
static const char *unsupported_options[] = {
TRANS_OPT_UPLOADPACK,
TRANS_OPT_RECEIVEPACK,
TRANS_OPT_THIN,
TRANS_OPT_KEEP
};
static const char *boolean_options[] = {
TRANS_OPT_THIN,
TRANS_OPT_KEEP,
TRANS_OPT_FOLLOWTAGS
};
static int set_helper_option(struct transport *transport,
const char *name, const char *value)
{
struct helper_data *data = transport->data;
struct strbuf buf = STRBUF_INIT;
int i, ret, is_bool = 0;
get_helper(transport);
if (!data->option)
return 1;
for (i = 0; i < ARRAY_SIZE(unsupported_options); i++) {
if (!strcmp(name, unsupported_options[i]))
return 1;
}
for (i = 0; i < ARRAY_SIZE(boolean_options); i++) {
if (!strcmp(name, boolean_options[i])) {
is_bool = 1;
break;
}
}
strbuf_addf(&buf, "option %s ", name);
if (is_bool)
strbuf_addstr(&buf, value ? "true" : "false");
else
quote_c_style(value, &buf, NULL, 0);
strbuf_addch(&buf, '\n');
xchgline(data, &buf);
if (!strcmp(buf.buf, "ok"))
ret = 0;
else if (!prefixcmp(buf.buf, "error")) {
ret = -1;
} else if (!strcmp(buf.buf, "unsupported"))
ret = 1;
else {
warning("%s unexpectedly said: '%s'", data->name, buf.buf);
ret = 1;
}
strbuf_release(&buf);
return ret;
}
static void standard_options(struct transport *t)
{
char buf[16];
int n;
int v = t->verbose;
int no_progress = v < 0 || (!t->progress && !isatty(1));
set_helper_option(t, "progress", !no_progress ? "true" : "false");
n = snprintf(buf, sizeof(buf), "%d", v + 1);
if (n >= sizeof(buf))
die("impossibly large verbosity value");
set_helper_option(t, "verbosity", buf);
}
static int release_helper(struct transport *transport)
{
struct helper_data *data = transport->data;
free_refspec(data->refspec_nr, data->refspecs);
data->refspecs = NULL;
disconnect_helper(transport);
free(transport->data);
return 0;
}
static int fetch_with_fetch(struct transport *transport,
int nr_heads, struct ref **to_fetch)
{
struct helper_data *data = transport->data;
int i;
struct strbuf buf = STRBUF_INIT;
standard_options(transport);
for (i = 0; i < nr_heads; i++) {
const struct ref *posn = to_fetch[i];
if (posn->status & REF_STATUS_UPTODATE)
continue;
strbuf_addf(&buf, "fetch %s %s\n",
sha1_to_hex(posn->old_sha1), posn->name);
}
strbuf_addch(&buf, '\n');
sendline(data, &buf);
while (1) {
recvline(data, &buf);
if (!prefixcmp(buf.buf, "lock ")) {
const char *name = buf.buf + 5;
if (transport->pack_lockfile)
warning("%s also locked %s", data->name, name);
else
transport->pack_lockfile = xstrdup(name);
}
else if (!buf.len)
break;
else
warning("%s unexpectedly said: '%s'", data->name, buf.buf);
}
strbuf_release(&buf);
return 0;
}
static int get_importer(struct transport *transport, struct child_process *fastimport)
{
struct child_process *helper = get_helper(transport);
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";
fastimport->git_cmd = 1;
return start_command(fastimport);
}
static int fetch_with_import(struct transport *transport,
int nr_heads, struct ref **to_fetch)
{
struct child_process fastimport;
struct helper_data *data = transport->data;
int i;
struct ref *posn;
struct strbuf buf = STRBUF_INIT;
get_helper(transport);
if (get_importer(transport, &fastimport))
die("Couldn't run fast-import");
for (i = 0; i < nr_heads; i++) {
posn = to_fetch[i];
if (posn->status & REF_STATUS_UPTODATE)
continue;
strbuf_addf(&buf, "import %s\n", posn->name);
sendline(data, &buf);
strbuf_reset(&buf);
}
disconnect_helper(transport);
finish_command(&fastimport);
free(fastimport.argv);
fastimport.argv = NULL;
for (i = 0; i < nr_heads; i++) {
char *private;
posn = to_fetch[i];
if (posn->status & REF_STATUS_UPTODATE)
continue;
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);
}
strbuf_release(&buf);
return 0;
}
static int process_connect_service(struct transport *transport,
const char *name, const char *exec)
{
struct helper_data *data = transport->data;
struct strbuf cmdbuf = STRBUF_INIT;
struct child_process *helper;
int r, duped, ret = 0;
FILE *input;
helper = get_helper(transport);
/*
* Yes, dup the pipe another time, as we need unbuffered version
* of input pipe as FILE*. fclose() closes the underlying fd and
* stream buffering only can be changed before first I/O operation
* on it.
*/
duped = dup(helper->out);
if (duped < 0)
die_errno("Can't dup helper output fd");
input = xfdopen(duped, "r");
setvbuf(input, NULL, _IONBF, 0);
/*
* Handle --upload-pack and friends. This is fire and forget...
* just warn if it fails.
*/
if (strcmp(name, exec)) {
r = set_helper_option(transport, "servpath", exec);
if (r > 0)
warning("Setting remote service path not supported by protocol.");
else if (r < 0)
warning("Invalid remote service path.");
}
if (data->connect)
strbuf_addf(&cmdbuf, "connect %s\n", name);
else
goto exit;
sendline(data, &cmdbuf);
recvline_fh(input, &cmdbuf);
if (!strcmp(cmdbuf.buf, "")) {
data->no_disconnect_req = 1;
if (debug)
fprintf(stderr, "Debug: Smart transport connection "
"ready.\n");
ret = 1;
} else if (!strcmp(cmdbuf.buf, "fallback")) {
if (debug)
fprintf(stderr, "Debug: Falling back to dumb "
"transport.\n");
} else
die("Unknown response to connect: %s",
cmdbuf.buf);
exit:
fclose(input);
return ret;
}
static int process_connect(struct transport *transport,
int for_push)
{
struct helper_data *data = transport->data;
const char *name;
const char *exec;
name = for_push ? "git-receive-pack" : "git-upload-pack";
if (for_push)
exec = data->transport_options.receivepack;
else
exec = data->transport_options.uploadpack;
return process_connect_service(transport, name, exec);
}
static int connect_helper(struct transport *transport, const char *name,
const char *exec, int fd[2])
{
struct helper_data *data = transport->data;
/* Get_helper so connect is inited. */
get_helper(transport);
if (!data->connect)
die("Operation not supported by protocol.");
if (!process_connect_service(transport, name, exec))
die("Can't connect to subservice %s.", name);
fd[0] = data->helper->out;
fd[1] = data->helper->in;
return 0;
}
static int fetch(struct transport *transport,
int nr_heads, struct ref **to_fetch)
{
struct helper_data *data = transport->data;
int i, count;
if (process_connect(transport, 0)) {
do_take_over(transport);
return transport->fetch(transport, nr_heads, to_fetch);
}
count = 0;
for (i = 0; i < nr_heads; i++)
if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
count++;
if (!count)
return 0;
if (data->fetch)
return fetch_with_fetch(transport, nr_heads, to_fetch);
if (data->import)
return fetch_with_import(transport, nr_heads, to_fetch);
return -1;
}
static int push_refs(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);
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)
continue;
ref->deletion = is_null_sha1(ref->new_sha1);
if (!ref->deletion &&
!hashcmp(ref->old_sha1, ref->new_sha1)) {
ref->status = REF_STATUS_UPTODATE;
continue;
}
if (force_all)
ref->force = 1;
strbuf_addstr(&buf, "push ");
if (!ref->deletion) {
if (ref->force)
strbuf_addch(&buf, '+');
if (ref->peer_ref)
strbuf_addstr(&buf, ref->peer_ref->name);
else
strbuf_addstr(&buf, sha1_to_hex(ref->new_sha1));
}
strbuf_addch(&buf, ':');
strbuf_addstr(&buf, ref->name);
strbuf_addch(&buf, '\n');
}
if (buf.len == 0)
return 0;
transport->verbose = flags & TRANSPORT_PUSH_VERBOSE ? 1 : 0;
standard_options(transport);
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);
}
strbuf_addch(&buf, '\n');
sendline(data, &buf);
ref = remote_refs;
while (1) {
char *refname, *msg;
int status;
recvline(data, &buf);
if (!buf.len)
break;
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);
continue;
}
ref->status = status;
ref->remote_status = msg;
}
strbuf_release(&buf);
return 0;
}
static int has_attribute(const char *attrs, const char *attr) {
int len;
if (!attrs)
return 0;
len = strlen(attr);
for (;;) {
const char *space = strchrnul(attrs, ' ');
if (len == space - attrs && !strncmp(attrs, attr, len))
return 1;
if (!*space)
return 0;
attrs = space + 1;
}
}
static struct ref *get_refs_list(struct transport *transport, int for_push)
{
struct helper_data *data = transport->data;
struct child_process *helper;
struct ref *ret = NULL;
struct ref **tail = &ret;
struct ref *posn;
struct strbuf buf = STRBUF_INIT;
helper = get_helper(transport);
if (process_connect(transport, for_push)) {
do_take_over(transport);
return transport->get_refs_list(transport, for_push);
}
if (data->push && for_push)
write_str_in_full(helper->in, "list for-push\n");
else
write_str_in_full(helper->in, "list\n");
while (1) {
char *eov, *eon;
recvline(data, &buf);
if (!*buf.buf)
break;
eov = strchr(buf.buf, ' ');
if (!eov)
die("Malformed response in ref list: %s", buf.buf);
eon = strchr(eov + 1, ' ');
*eov = '\0';
if (eon)
*eon = '\0';
*tail = alloc_ref(eov + 1);
if (buf.buf[0] == '@')
(*tail)->symref = xstrdup(buf.buf + 1);
else if (buf.buf[0] != '?')
get_sha1_hex(buf.buf, (*tail)->old_sha1);
if (eon) {
if (has_attribute(eon + 1, "unchanged")) {
(*tail)->status |= REF_STATUS_UPTODATE;
read_ref((*tail)->name, (*tail)->old_sha1);
}
}
tail = &((*tail)->next);
}
if (debug)
fprintf(stderr, "Debug: Read ref listing.\n");
strbuf_release(&buf);
for (posn = ret; posn; posn = posn->next)
resolve_remote_symref(posn, ret);
return ret;
}
int transport_helper_init(struct transport *transport, const char *name)
{
struct helper_data *data = xcalloc(sizeof(*data), 1);
data->name = name;
if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
debug = 1;
transport->data = data;
transport->set_option = set_helper_option;
transport->get_refs_list = get_refs_list;
transport->fetch = fetch;
transport->push_refs = push_refs;
transport->disconnect = release_helper;
transport->connect = connect_helper;
transport->smart_options = &(data->transport_options);
return 0;
}