1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
|
#include "cache.h"
#include "refs.h"
#include "pkt-line.h"
#include <sys/wait.h>
static const char fetch_pack_usage[] = "git-fetch-pack [host:]directory [heads]* < mycommitlist";
static const char *exec = "git-upload-pack";
static int find_common(int fd[2], unsigned char *result_sha1, unsigned char *remote)
{
static char line[1000];
int count = 0, flushes = 0, retval;
FILE *revs;
revs = popen("git-rev-list $(git-rev-parse --all)", "r");
if (!revs)
die("unable to run 'git-rev-list'");
packet_write(fd[1], "want %s\n", sha1_to_hex(remote));
packet_flush(fd[1]);
flushes = 1;
retval = -1;
while (fgets(line, sizeof(line), revs) != NULL) {
unsigned char sha1[20];
if (get_sha1_hex(line, sha1))
die("git-fetch-pack: expected object name, got crud");
packet_write(fd[1], "have %s\n", sha1_to_hex(sha1));
if (!(31 & ++count)) {
packet_flush(fd[1]);
flushes++;
/*
* We keep one window "ahead" of the other side, and
* will wait for an ACK only on the next one
*/
if (count == 32)
continue;
if (get_ack(fd[0], result_sha1)) {
flushes = 0;
retval = 0;
break;
}
flushes--;
}
}
pclose(revs);
packet_write(fd[1], "done\n");
while (flushes) {
flushes--;
if (get_ack(fd[0], result_sha1))
return 0;
}
return retval;
}
static int get_remote_heads(int fd, int nr_match, char **match, unsigned char *result)
{
int count = 0;
for (;;) {
static char line[1000];
unsigned char sha1[20];
char *refname;
int len;
len = packet_read_line(fd, line, sizeof(line));
if (!len)
break;
if (line[len-1] == '\n')
line[--len] = 0;
if (len < 42 || get_sha1_hex(line, sha1))
die("git-fetch-pack: protocol error - expected ref descriptor, got '%s¤'", line);
refname = line+41;
if (nr_match && !path_match(refname, nr_match, match))
continue;
count++;
memcpy(result, sha1, 20);
}
return count;
}
static int fetch_pack(int fd[2], int nr_match, char **match)
{
unsigned char sha1[20], remote[20];
int heads, status;
pid_t pid;
heads = get_remote_heads(fd[0], nr_match, match, remote);
if (heads != 1) {
packet_flush(fd[1]);
die(heads ? "multiple remote heads" : "no matching remote head");
}
if (find_common(fd, sha1, remote) < 0)
die("git-fetch-pack: no common commits");
pid = fork();
if (pid < 0)
die("git-fetch-pack: unable to fork off git-unpack-objects");
if (!pid) {
close(fd[1]);
dup2(fd[0], 0);
close(fd[0]);
execlp("git-unpack-objects", "git-unpack-objects", NULL);
die("git-unpack-objects exec failed");
}
close(fd[0]);
close(fd[1]);
while (waitpid(pid, &status, 0) < 0) {
if (errno != EINTR)
die("waiting for git-unpack-objects: %s", strerror(errno));
}
if (WIFEXITED(status)) {
int code = WEXITSTATUS(status);
if (code)
die("git-unpack-objects died with error code %d", code);
puts(sha1_to_hex(remote));
return 0;
}
if (WIFSIGNALED(status)) {
int sig = WTERMSIG(status);
die("git-unpack-objects died of signal %d", sig);
}
die("Sherlock Holmes! git-unpack-objects died of unnatural causes %d!", status);
}
int main(int argc, char **argv)
{
int i, ret, nr_heads;
char *dest = NULL, **heads;
int fd[2];
pid_t pid;
nr_heads = 0;
heads = NULL;
for (i = 1; i < argc; i++) {
char *arg = argv[i];
if (*arg == '-') {
/* Arguments go here */
usage(fetch_pack_usage);
}
dest = arg;
heads = argv + i + 1;
nr_heads = argc - i - 1;
break;
}
if (!dest)
usage(fetch_pack_usage);
pid = git_connect(fd, dest, exec);
if (pid < 0)
return 1;
ret = fetch_pack(fd, nr_heads, heads);
close(fd[0]);
close(fd[1]);
finish_connect(pid);
return ret;
}
|
