upload-pack.c

   1 #include "cache.h"
   2 #include "refs.h"
   3 #include "pkt-line.h"
   4
   5 static const char upload_pack_usage[] = "git-upload-pack <dir>";
   6
   7 #define MAX_HAS (16)
   8 #define MAX_NEEDS (16)
   9 static int nr_has = 0, nr_needs = 0;
  10 static unsigned char has_sha1[MAX_HAS][20];
  11 static unsigned char needs_sha1[MAX_NEEDS][20];
  12
  13 static void create_pack_file(void)
  14 {
  15         /*
  16          * Here, we should do
  17          *
  18          *      git-rev-list --objects needs_sha1 --not has_sha1 |
  19          *              git-pack-objects --stdout
  20          *
  21          * but we don't.
  22          */
  23 }
  24
  25 static int got_sha1(char *hex, unsigned char *sha1)
  26 {
  27         int nr;
  28         if (get_sha1_hex(hex, sha1))
  29                 die("git-upload-pack: expected SHA1 object, got '%s'", hex);
  30         if (!has_sha1_file(sha1))
  31                 return 0;
  32         nr = nr_has;
  33         if (nr < MAX_HAS) {
  34                 memcpy(has_sha1[nr], sha1, 20);
  35                 nr_has = nr+1;
  36         }
  37         return 1;
  38 }
  39
  40 static int get_common_commits(void)
  41 {
  42         static char line[1000];
  43         unsigned char sha1[20];
  44         int len;
  45
  46         for(;;) {
  47                 len = packet_read_line(0, line, sizeof(line));
  48
  49                 if (!len) {
  50                         packet_write(1, "NAK\n");
  51                         continue;
  52                 }
  53                 if (line[len-1] == '\n')
  54                         line[--len] = 0;
  55                 if (!strncmp(line, "have ", 5)) {
  56                         if (got_sha1(line+5, sha1)) {
  57                                 packet_write(1, "ACK %s\n", sha1_to_hex(sha1));
  58                                 break;
  59                         }
  60                         continue;
  61                 }
  62                 if (!strcmp(line, "done")) {
  63                         packet_write(1, "NAK\n");
  64                         return -1;
  65                 }
  66                 die("git-upload-pack: expected SHA1 list, got '%s'", line);
  67         }
  68
  69         for (;;) {
  70                 len = packet_read_line(0, line, sizeof(line));
  71                 if (!len)
  72                         break;
  73                 if (!strncmp(line, "have ", 5)) {
  74                         got_sha1(line+5, sha1);
  75                         continue;
  76                 }
  77                 if (!strcmp(line, "done"))
  78                         break;
  79                 die("git-upload-pack: expected SHA1 list, got '%s'", line);
  80         }
  81         return 0;
  82 }
  83
  84 static int receive_needs(void)
  85 {
  86         static char line[1000];
  87         int len, needs;
  88
  89         needs = 0;
  90         for (;;) {
  91                 len = packet_read_line(0, line, sizeof(line));
  92                 if (!len)
  93                         return needs;
  94
  95                 /*
  96                  * This is purely theoretical right now: git-fetch-pack only
  97                  * ever asks for a single HEAD
  98                  */
  99                 if (needs >= MAX_NEEDS)
 100                         die("I'm only doing a max of %d requests", MAX_NEEDS);
 101                 if (strncmp("want ", line, 5) || get_sha1_hex(line+5, needs_sha1[needs]))
 102                         die("git-upload-pack: protocol error, expected to get sha, not '%s'", line);
 103                 needs++;
 104         }
 105 }
 106
 107 static int send_ref(const char *refname, const unsigned char *sha1)
 108 {
 109         packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname);
 110         return 0;
 111 }
 112
 113 static int upload_pack(void)
 114 {
 115         for_each_ref(send_ref);
 116         packet_flush(1);
 117         nr_needs = receive_needs();
 118         if (!nr_needs)
 119                 return 0;
 120         get_common_commits();
 121         create_pack_file();
 122         return 0;
 123 }
 124
 125 int main(int argc, char **argv)
 126 {
 127         const char *dir;
 128         if (argc != 2)
 129                 usage(upload_pack_usage);
 130         dir = argv[1];
 131         if (chdir(dir))
 132                 die("git-upload-pack unable to chdir to %s", dir);
 133         chdir(".git");
 134         if (access("objects", X_OK) || access("refs", X_OK))
 135                 die("git-upload-pack: %s doesn't seem to be a git archive", dir);
 136         setenv("GIT_DIR", ".", 1);
 137         upload_pack();
 138         return 0;
 139 }