git/send-pack.c

292 lines
6.3 KiB
C
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#include "cache.h"
#include "pkt-line.h"
#include <sys/wait.h>
static const char send_pack_usage[] = "git-send-pack [--exec=other] destination [heads]*";
static const char *exec = "git-receive-pack";
static int path_match(const char *path, int nr, char **match)
{
int i;
int pathlen = strlen(path);
for (i = 0; i < nr; i++) {
char *s = match[i];
int len = strlen(s);
if (!len || len > pathlen)
continue;
if (memcmp(path + pathlen - len, s, len))
continue;
if (pathlen > len && path[pathlen - len - 1] != '/')
continue;
*s = 0;
return 1;
}
return 0;
}
struct ref {
struct ref *next;
unsigned char old_sha1[20];
unsigned char new_sha1[20];
char name[0];
};
static void exec_pack_objects(void)
{
static char *args[] = {
"git-pack-objects",
"--stdout",
NULL
};
execvp("git-pack-objects", args);
die("git-pack-objects exec failed (%s)", strerror(errno));
}
static void exec_rev_list(struct ref *refs)
{
static char *args[1000];
int i = 0;
args[i++] = "git-rev-list"; /* 0 */
args[i++] = "--objects"; /* 1 */
while (refs) {
char *buf = malloc(100);
if (i > 900)
die("git-rev-list environment overflow");
args[i++] = buf;
snprintf(buf, 50, "^%s", sha1_to_hex(refs->old_sha1));
buf += 50;
args[i++] = buf;
snprintf(buf, 50, "%s", sha1_to_hex(refs->new_sha1));
refs = refs->next;
}
args[i] = NULL;
execvp("git-rev-list", args);
die("git-rev-list exec failed (%s)", strerror(errno));
}
static void rev_list(int fd, struct ref *refs)
{
int pipe_fd[2];
pid_t pack_objects_pid;
if (pipe(pipe_fd) < 0)
die("rev-list setup: pipe failed");
pack_objects_pid = fork();
if (!pack_objects_pid) {
dup2(pipe_fd[0], 0);
dup2(fd, 1);
close(pipe_fd[0]);
close(pipe_fd[1]);
close(fd);
exec_pack_objects();
die("pack-objects setup failed");
}
if (pack_objects_pid < 0)
die("pack-objects fork failed");
dup2(pipe_fd[1], 1);
close(pipe_fd[0]);
close(pipe_fd[1]);
close(fd);
exec_rev_list(refs);
}
static int pack_objects(int fd, struct ref *refs)
{
pid_t rev_list_pid;
rev_list_pid = fork();
if (!rev_list_pid) {
rev_list(fd, refs);
die("rev-list setup failed");
}
if (rev_list_pid < 0)
die("rev-list fork failed");
/*
* We don't wait for the rev-list pipeline in the parent:
* we end up waiting for the other end instead
*/
return 0;
}
static int read_ref(const char *ref, unsigned char *sha1)
{
int fd, ret;
static char pathname[PATH_MAX];
char buffer[60];
const char *git_dir = gitenv(GIT_DIR_ENVIRONMENT) ? : DEFAULT_GIT_DIR_ENVIRONMENT;
snprintf(pathname, sizeof(pathname), "%s/%s", git_dir, ref);
fd = open(pathname, O_RDONLY);
if (fd < 0)
return -1;
ret = -1;
if (read(fd, buffer, sizeof(buffer)) >= 40)
ret = get_sha1_hex(buffer, sha1);
close(fd);
return ret;
}
static int send_pack(int in, int out, int nr_match, char **match)
{
struct ref *ref_list = NULL, **last_ref = &ref_list;
struct ref *ref;
for (;;) {
unsigned char old_sha1[20];
unsigned char new_sha1[20];
static char buffer[1000];
char *name;
int len;
len = packet_read_line(in, buffer, sizeof(buffer));
if (!len)
break;
if (buffer[len-1] == '\n')
buffer[--len] = 0;
if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
die("protocol error: expected sha/ref, got '%s'", buffer);
name = buffer + 41;
if (nr_match && !path_match(name, nr_match, match))
continue;
if (read_ref(name, new_sha1) < 0)
return error("no such local reference '%s'", name);
if (!has_sha1_file(old_sha1))
return error("remote '%s' points to object I don't have", name);
if (!memcmp(old_sha1, new_sha1, 20)) {
fprintf(stderr, "'%s' unchanged\n", name);
continue;
}
ref = xmalloc(sizeof(*ref) + len - 40);
memcpy(ref->old_sha1, old_sha1, 20);
memcpy(ref->new_sha1, new_sha1, 20);
memcpy(ref->name, buffer + 41, len - 40);
ref->next = NULL;
*last_ref = ref;
last_ref = &ref->next;
}
for (ref = ref_list; ref; ref = ref->next) {
char old_hex[60], *new_hex;
strcpy(old_hex, sha1_to_hex(ref->old_sha1));
new_hex = sha1_to_hex(ref->new_sha1);
packet_write(out, "%s %s %s", old_hex, new_hex, ref->name);
fprintf(stderr, "'%s': updating from %s to %s\n", ref->name, old_hex, new_hex);
}
packet_flush(out);
if (ref_list)
pack_objects(out, ref_list);
close(out);
return 0;
}
/*
* First, make it shell-safe. We do this by just disallowing any
* special characters. Somebody who cares can do escaping and let
* through the rest. But since we're doing to feed this to ssh as
* a command line, we're going to be pretty damn anal for now.
*/
static char *shell_safe(char *url)
{
char *n = url;
unsigned char c;
static const char flags[256] = {
['0'...'9'] = 1,
['a'...'z'] = 1,
['A'...'Z'] = 1,
['.'] = 1, ['/'] = 1,
['-'] = 1, ['+'] = 1,
[':'] = 1
};
while ((c = *n++) != 0) {
if (flags[c] != 1)
die("I don't like '%c'. Sue me.", c);
}
return url;
}
/*
* Yeah, yeah, fixme. Need to pass in the heads etc.
*/
static int setup_connection(int fd[2], char *url, char **heads)
{
char command[1024];
const char *host, *path;
char *colon;
int pipefd[2][2];
pid_t pid;
url = shell_safe(url);
host = NULL;
path = url;
colon = strchr(url, ':');
if (colon) {
*colon = 0;
host = url;
path = colon+1;
}
snprintf(command, sizeof(command), "%s %s", exec, path);
if (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
die("unable to create pipe pair for communication");
pid = fork();
if (!pid) {
dup2(pipefd[1][0], 0);
dup2(pipefd[0][1], 1);
close(pipefd[0][0]);
close(pipefd[0][1]);
close(pipefd[1][0]);
close(pipefd[1][1]);
if (host)
execlp("ssh", "ssh", host, command, NULL);
else
execlp("sh", "sh", "-c", command, NULL);
die("exec failed");
}
fd[0] = pipefd[0][0];
fd[1] = pipefd[1][1];
close(pipefd[0][1]);
close(pipefd[1][0]);
return pid;
}
int main(int argc, char **argv)
{
int i, nr_heads = 0;
char *dest = NULL;
char **heads = NULL;
int fd[2], ret;
pid_t pid;
argv++;
for (i = 1; i < argc; i++) {
char *arg = *argv++;
if (*arg == '-') {
if (!strncmp(arg, "--exec=", 7)) {
exec = arg + 7;
continue;
}
usage(send_pack_usage);
}
dest = arg;
heads = argv;
nr_heads = argc - i -1;
break;
}
if (!dest)
usage(send_pack_usage);
pid = setup_connection(fd, dest, heads);
if (pid < 0)
return 1;
ret = send_pack(fd[0], fd[1], nr_heads, heads);
close(fd[0]);
close(fd[1]);
waitpid(pid, NULL, 0);
return ret;
}