receive-pack.c

   1 #include "cache.h"
   2 #include "pkt-line.h"
   3 #include <sys/wait.h>
   4
   5 static const char receive_pack_usage[] = "git-receive-pack [--unpack=executable] <git-dir> [heads]";
   6
   7 static const char *unpacker = "git-unpack-objects";
   8
   9 static int path_match(const char *path, int nr, char **match)
  10 {
  11         int i;
  12         int pathlen = strlen(path);
  13
  14         for (i = 0; i < nr; i++) {
  15                 char *s = match[i];
  16                 int len = strlen(s);
  17
  18                 if (!len || len > pathlen)
  19                         continue;
  20                 if (memcmp(path + pathlen - len, s, len))
  21                         continue;
  22                 if (pathlen > len && path[pathlen - len - 1] != '/')
  23                         continue;
  24                 *s = 0;
  25                 return 1;
  26         }
  27         return 0;
  28 }
  29
  30 static void show_ref(const char *path, unsigned char *sha1)
  31 {
  32         packet_write(1, "%s %s\n", sha1_to_hex(sha1), path);
  33 }
  34
  35 static int read_ref(const char *path, unsigned char *sha1)
  36 {
  37         int ret = -1;
  38         int fd = open(path, O_RDONLY);
  39
  40         if (fd >= 0) {
  41                 char buffer[60];
  42                 if (read(fd, buffer, sizeof(buffer)) >= 40)
  43                         ret = get_sha1_hex(buffer, sha1);
  44                 close(fd);
  45         }
  46         return ret;
  47 }
  48
  49 static void write_head_info(const char *base, int nr, char **match)
  50 {
  51         DIR *dir = opendir(base);
  52
  53         if (dir) {
  54                 struct dirent *de;
  55                 int baselen = strlen(base);
  56                 char *path = xmalloc(baselen + 257);
  57                 memcpy(path, base, baselen);
  58
  59                 while ((de = readdir(dir)) != NULL) {
  60                         char sha1[20];
  61                         struct stat st;
  62                         int namelen;
  63
  64                         if (de->d_name[0] == '.')
  65                                 continue;
  66                         namelen = strlen(de->d_name);
  67                         if (namelen > 255)
  68                                 continue;
  69                         memcpy(path + baselen, de->d_name, namelen+1);
  70                         if (lstat(path, &st) < 0)
  71                                 continue;
  72                         if (S_ISDIR(st.st_mode)) {
  73                                 path[baselen + namelen] = '/';
  74                                 path[baselen + namelen + 1] = 0;
  75                                 write_head_info(path, nr, match);
  76                                 continue;
  77                         }
  78                         if (read_ref(path, sha1) < 0)
  79                                 continue;
  80                         if (nr && !path_match(path, nr, match))
  81                                 continue;
  82                         show_ref(path, sha1);
  83                 }
  84                 free(path);
  85                 closedir(dir);
  86         }
  87 }
  88
  89 struct line {
  90         struct line *next;
  91         char data[0];
  92 };
  93
  94 struct line *commands = NULL;
  95
  96 /*
  97  * This gets called after(if) we've successfully
  98  * unpacked the data payload.
  99  */
 100 static void execute_commands(void)
 101 {
 102         struct line *line = commands;
 103
 104         while (line) {
 105                 fprintf(stderr, "%s", line->data);
 106                 line = line->next;
 107         }
 108 }
 109
 110 static void read_head_info(void)
 111 {
 112         struct line **p = &commands;
 113         for (;;) {
 114                 static char line[1000];
 115                 int len = packet_read_line(0, line, sizeof(line));
 116                 struct line *n;
 117                 if (!len)
 118                         break;
 119                 n = xmalloc(sizeof(struct line) + len);
 120                 n->next = NULL;
 121                 memcpy(n->data, line + 4, len - 3);
 122                 *p = n;
 123                 p = &n->next;
 124         }
 125 }
 126
 127 static void unpack(void)
 128 {
 129         pid_t pid = fork();
 130
 131         if (pid < 0)
 132                 die("unpack fork failed");
 133         if (!pid) {
 134                 setenv("GIT_DIR", ".", 1);
 135                 execlp(unpacker, unpacker, NULL);
 136                 die("unpack execute failed");
 137         }
 138
 139         for (;;) {
 140                 int status, code;
 141                 int retval = waitpid(pid, &status, 0);
 142
 143                 if (retval < 0) {
 144                         if (errno == EINTR)
 145                                 continue;
 146                         die("waitpid failed (%s)", strerror(retval));
 147                 }
 148                 if (retval != pid)
 149                         die("waitpid is confused");
 150                 if (WIFSIGNALED(status))
 151                         die("%s died of signal %d", unpacker, WTERMSIG(status));
 152                 if (!WIFEXITED(status))
 153                         die("%s died out of really strange complications", unpacker);
 154                 code = WEXITSTATUS(status);
 155                 if (code)
 156                         die("%s exited with error code %d", unpacker, code);
 157                 return;
 158         }
 159 }
 160
 161 int main(int argc, char **argv)
 162 {
 163         int i, nr_heads = 0;
 164         const char *dir = NULL;
 165         char **heads = NULL;
 166
 167         argv++;
 168         for (i = 1; i < argc; i++) {
 169                 const char *arg = *argv++;
 170
 171                 if (*arg == '-') {
 172                         if (!strncmp(arg, "--unpack=", 9)) {
 173                                 unpacker = arg+9;
 174                                 continue;
 175                         }
 176                         /* Do flag handling here */
 177                         usage(receive_pack_usage);
 178                 }
 179                 dir = arg;
 180                 heads = argv;
 181                 nr_heads = argc - i - 1;
 182                 break;
 183         }
 184         if (!dir)
 185                 usage(receive_pack_usage);
 186
 187         /* chdir to the directory. If that fails, try appending ".git" */
 188         if (chdir(dir) < 0) {
 189                 static char path[PATH_MAX];
 190                 snprintf(path, sizeof(path), "%s.git", dir);
 191                 if (chdir(path) < 0)
 192                         die("unable to cd to %s", dir);
 193         }
 194
 195         /* If we have a ".git" directory, chdir to it */
 196         chdir(".git");
 197
 198         if (access("objects", X_OK) < 0 || access("refs/heads", X_OK) < 0)
 199                 die("%s doesn't appear to be a git directory", dir);
 200         write_head_info("refs/", nr_heads, heads);
 201
 202         /* EOF */
 203         packet_flush(1);
 204
 205         read_head_info();
 206         unpack();
 207         execute_commands();
 208         return 0;
 209 }