git/ssh-fetch.c
Daniel Barkalow 70a0c6fe39 [PATCH] Limit the number of requests outstanding in ssh-fetch.
This completes fetches if there are more than 100 outstanding requests
and there are more to prefetch.

Signed-off-by: Daniel Barkalow <barkalow@iabervon.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2005-10-03 21:55:31 -07:00

171 lines
3.5 KiB
C

#ifndef COUNTERPART_ENV_NAME
#define COUNTERPART_ENV_NAME "GIT_SSH_UPLOAD"
#endif
#ifndef COUNTERPART_PROGRAM_NAME
#define COUNTERPART_PROGRAM_NAME "git-ssh-upload"
#endif
#ifndef MY_PROGRAM_NAME
#define MY_PROGRAM_NAME "git-ssh-fetch"
#endif
#include "cache.h"
#include "commit.h"
#include "rsh.h"
#include "fetch.h"
#include "refs.h"
static int fd_in;
static int fd_out;
static unsigned char remote_version = 0;
static unsigned char local_version = 1;
static ssize_t force_write(int fd, void *buffer, size_t length)
{
ssize_t ret = 0;
while (ret < length) {
ssize_t size = write(fd, buffer + ret, length - ret);
if (size < 0) {
return size;
}
if (size == 0) {
return ret;
}
ret += size;
}
return ret;
}
static int prefetches = 0;
static struct object_list *in_transit = NULL;
static struct object_list **end_of_transit = &in_transit;
void prefetch(unsigned char *sha1)
{
char type = 'o';
struct object_list *node;
if (prefetches > 100) {
fetch(in_transit->item->sha1);
}
node = xmalloc(sizeof(struct object_list));
node->next = NULL;
node->item = lookup_unknown_object(sha1);
*end_of_transit = node;
end_of_transit = &node->next;
force_write(fd_out, &type, 1);
force_write(fd_out, sha1, 20);
prefetches++;
}
static char conn_buf[4096];
static size_t conn_buf_posn = 0;
int fetch(unsigned char *sha1)
{
int ret;
signed char remote;
struct object_list *temp;
if (memcmp(sha1, in_transit->item->sha1, 20)) {
// we must have already fetched it to clean the queue
return has_sha1_file(sha1) ? 0 : -1;
}
prefetches--;
temp = in_transit;
in_transit = in_transit->next;
if (!in_transit)
end_of_transit = &in_transit;
free(temp);
if (conn_buf_posn) {
remote = conn_buf[0];
memmove(conn_buf, conn_buf + 1, --conn_buf_posn);
} else {
if (read(fd_in, &remote, 1) < 1)
return -1;
}
//fprintf(stderr, "Got %d\n", remote);
if (remote < 0)
return remote;
ret = write_sha1_from_fd(sha1, fd_in, conn_buf, 4096, &conn_buf_posn);
if (!ret)
pull_say("got %s\n", sha1_to_hex(sha1));
return ret;
}
static int get_version(void)
{
char type = 'v';
write(fd_out, &type, 1);
write(fd_out, &local_version, 1);
if (read(fd_in, &remote_version, 1) < 1) {
return error("Couldn't read version from remote end");
}
return 0;
}
int fetch_ref(char *ref, unsigned char *sha1)
{
signed char remote;
char type = 'r';
write(fd_out, &type, 1);
write(fd_out, ref, strlen(ref) + 1);
read(fd_in, &remote, 1);
if (remote < 0)
return remote;
read(fd_in, sha1, 20);
return 0;
}
static const char ssh_fetch_usage[] =
MY_PROGRAM_NAME
" [-c] [-t] [-a] [-v] [-d] [--recover] [-w ref] commit-id url";
int main(int argc, char **argv)
{
char *commit_id;
char *url;
int arg = 1;
const char *prog;
prog = getenv("GIT_SSH_PUSH");
if (!prog) prog = "git-ssh-upload";
while (arg < argc && argv[arg][0] == '-') {
if (argv[arg][1] == 't') {
get_tree = 1;
} else if (argv[arg][1] == 'c') {
get_history = 1;
} else if (argv[arg][1] == 'a') {
get_all = 1;
get_tree = 1;
get_history = 1;
} else if (argv[arg][1] == 'v') {
get_verbosely = 1;
} else if (argv[arg][1] == 'w') {
write_ref = argv[arg + 1];
arg++;
} else if (!strcmp(argv[arg], "--recover")) {
get_recover = 1;
}
arg++;
}
if (argc < arg + 2) {
usage(ssh_fetch_usage);
return 1;
}
commit_id = argv[arg];
url = argv[arg + 1];
if (setup_connection(&fd_in, &fd_out, prog, url, arg, argv + 1))
return 1;
if (get_version())
return 1;
if (pull(commit_id))
return 1;
return 0;
}