21b4b8b7575dd3ceb2fdf40b5aa4b7483168ec1e
[git/git.git] / upload-pack.c
1 #include "cache.h"
2 #include "refs.h"
3 #include "pkt-line.h"
4 #include "tag.h"
5 #include "object.h"
6
7 static const char upload_pack_usage[] = "git-upload-pack <dir>";
8
9 #define MAX_HAS (16)
10 #define MAX_NEEDS (256)
11 static int nr_has = 0, nr_needs = 0;
12 static unsigned char has_sha1[MAX_HAS][20];
13 static unsigned char needs_sha1[MAX_NEEDS][20];
14
15 static int strip(char *line, int len)
16 {
17 if (len && line[len-1] == '\n')
18 line[--len] = 0;
19 return len;
20 }
21
22 static void create_pack_file(void)
23 {
24 int fd[2];
25 pid_t pid;
26
27 if (pipe(fd) < 0)
28 die("git-upload-pack: unable to create pipe");
29 pid = fork();
30 if (pid < 0)
31 die("git-upload-pack: unable to fork git-rev-list");
32
33 if (!pid) {
34 int i;
35 int args;
36 char **argv;
37 char *buf;
38 char **p;
39
40 if (MAX_NEEDS <= nr_needs)
41 args = nr_has + 10;
42 else
43 args = nr_has + nr_needs + 5;
44 argv = xmalloc(args * sizeof(char *));
45 buf = xmalloc(args * 45);
46 p = argv;
47
48 dup2(fd[1], 1);
49 close(0);
50 close(fd[0]);
51 close(fd[1]);
52 *p++ = "git-rev-list";
53 *p++ = "--objects";
54 if (MAX_NEEDS <= nr_needs)
55 *p++ = "--all";
56 else {
57 for (i = 0; i < nr_needs; i++) {
58 *p++ = buf;
59 memcpy(buf, sha1_to_hex(needs_sha1[i]), 41);
60 buf += 41;
61 }
62 }
63 for (i = 0; i < nr_has; i++) {
64 *p++ = buf;
65 *buf++ = '^';
66 memcpy(buf, sha1_to_hex(has_sha1[i]), 41);
67 buf += 41;
68 }
69 *p++ = NULL;
70 execvp("git-rev-list", argv);
71 die("git-upload-pack: unable to exec git-rev-list");
72 }
73 dup2(fd[0], 0);
74 close(fd[0]);
75 close(fd[1]);
76 execlp("git-pack-objects", "git-pack-objects", "--stdout", NULL);
77 die("git-upload-pack: unable to exec git-pack-objects");
78 }
79
80 static int got_sha1(char *hex, unsigned char *sha1)
81 {
82 int nr;
83 if (get_sha1_hex(hex, sha1))
84 die("git-upload-pack: expected SHA1 object, got '%s'", hex);
85 if (!has_sha1_file(sha1))
86 return 0;
87 nr = nr_has;
88 if (nr < MAX_HAS) {
89 memcpy(has_sha1[nr], sha1, 20);
90 nr_has = nr+1;
91 }
92 return 1;
93 }
94
95 static int get_common_commits(void)
96 {
97 static char line[1000];
98 unsigned char sha1[20];
99 int len;
100
101 for(;;) {
102 len = packet_read_line(0, line, sizeof(line));
103
104 if (!len) {
105 packet_write(1, "NAK\n");
106 continue;
107 }
108 len = strip(line, len);
109 if (!strncmp(line, "have ", 5)) {
110 if (got_sha1(line+5, sha1)) {
111 packet_write(1, "ACK %s\n", sha1_to_hex(sha1));
112 break;
113 }
114 continue;
115 }
116 if (!strcmp(line, "done")) {
117 packet_write(1, "NAK\n");
118 return -1;
119 }
120 die("git-upload-pack: expected SHA1 list, got '%s'", line);
121 }
122
123 for (;;) {
124 len = packet_read_line(0, line, sizeof(line));
125 if (!len)
126 continue;
127 len = strip(line, len);
128 if (!strncmp(line, "have ", 5)) {
129 got_sha1(line+5, sha1);
130 continue;
131 }
132 if (!strcmp(line, "done"))
133 break;
134 die("git-upload-pack: expected SHA1 list, got '%s'", line);
135 }
136 return 0;
137 }
138
139 static int receive_needs(void)
140 {
141 static char line[1000];
142 int len, needs;
143
144 needs = 0;
145 for (;;) {
146 unsigned char dummy[20], *sha1_buf;
147 len = packet_read_line(0, line, sizeof(line));
148 if (!len)
149 return needs;
150
151 sha1_buf = dummy;
152 if (needs == MAX_NEEDS) {
153 fprintf(stderr,
154 "warning: supporting only a max of %d requests. "
155 "sending everything instead.\n",
156 MAX_NEEDS);
157 }
158 else if (needs < MAX_NEEDS)
159 sha1_buf = needs_sha1[needs];
160
161 if (strncmp("want ", line, 5) || get_sha1_hex(line+5, sha1_buf))
162 die("git-upload-pack: protocol error, "
163 "expected to get sha, not '%s'", line);
164 needs++;
165 }
166 }
167
168 static int send_ref(const char *refname, const unsigned char *sha1)
169 {
170 struct object *o = parse_object(sha1);
171
172 packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname);
173 if (o->type == tag_type) {
174 o = deref_tag(o);
175 packet_write(1, "%s %s^{}\n", sha1_to_hex(o->sha1), refname);
176 }
177 return 0;
178 }
179
180 static int upload_pack(void)
181 {
182 head_ref(send_ref);
183 for_each_ref(send_ref);
184 packet_flush(1);
185 nr_needs = receive_needs();
186 if (!nr_needs)
187 return 0;
188 get_common_commits();
189 create_pack_file();
190 return 0;
191 }
192
193 int main(int argc, char **argv)
194 {
195 const char *dir;
196 if (argc != 2)
197 usage(upload_pack_usage);
198 dir = argv[1];
199
200 /* chdir to the directory. If that fails, try appending ".git" */
201 if (chdir(dir) < 0) {
202 if (chdir(mkpath("%s.git", dir)) < 0)
203 die("git-upload-pack unable to chdir to %s", dir);
204 }
205 chdir(".git");
206 if (access("objects", X_OK) || access("refs", X_OK))
207 die("git-upload-pack: %s doesn't seem to be a git archive", dir);
208 putenv("GIT_DIR=.");
209 upload_pack();
210 return 0;
211 }