Andrew's git - gitweb.git/blob

   1#include "cache.h"
   2#include "refs.h"
   3#include "pkt-line.h"
   4
   5static const char send_pack_usage[] =
   6"git-send-pack [--exec=git-receive-pack] [host:]directory [heads]*";
   7static const char *exec = "git-receive-pack";
   8
   9struct ref {
  10        struct ref *next;
  11        unsigned char old_sha1[20];
  12        unsigned char new_sha1[20];
  13        char name[0];
  14};
  15
  16static int is_zero_sha1(const unsigned char *sha1)
  17{
  18        int i;
  19
  20        for (i = 0; i < 20; i++) {
  21                if (*sha1++)
  22                        return 0;
  23        }
  24        return 1;
  25}
  26
  27static void exec_pack_objects(void)
  28{
  29        static char *args[] = {
  30                "git-pack-objects",
  31                "--stdout",
  32                NULL
  33        };
  34        execvp("git-pack-objects", args);
  35        die("git-pack-objects exec failed (%s)", strerror(errno));
  36}
  37
  38static void exec_rev_list(struct ref *refs)
  39{
  40        static char *args[1000];
  41        int i = 0;
  42
  43        args[i++] = "git-rev-list";     /* 0 */
  44        args[i++] = "--objects";        /* 1 */
  45        while (refs) {
  46                char *buf = malloc(100);
  47                if (i > 900)
  48                        die("git-rev-list environment overflow");
  49                if (!is_zero_sha1(refs->old_sha1)) {
  50                        args[i++] = buf;
  51                        snprintf(buf, 50, "^%s", sha1_to_hex(refs->old_sha1));
  52                        buf += 50;
  53                }
  54                if (!is_zero_sha1(refs->new_sha1)) {
  55                        args[i++] = buf;
  56                        snprintf(buf, 50, "%s", sha1_to_hex(refs->new_sha1));
  57                }
  58                refs = refs->next;
  59        }
  60        args[i] = NULL;
  61        execvp("git-rev-list", args);
  62        die("git-rev-list exec failed (%s)", strerror(errno));
  63}
  64
  65static void rev_list(int fd, struct ref *refs)
  66{
  67        int pipe_fd[2];
  68        pid_t pack_objects_pid;
  69
  70        if (pipe(pipe_fd) < 0)
  71                die("rev-list setup: pipe failed");
  72        pack_objects_pid = fork();
  73        if (!pack_objects_pid) {
  74                dup2(pipe_fd[0], 0);
  75                dup2(fd, 1);
  76                close(pipe_fd[0]);
  77                close(pipe_fd[1]);
  78                close(fd);
  79                exec_pack_objects();
  80                die("pack-objects setup failed");
  81        }
  82        if (pack_objects_pid < 0)
  83                die("pack-objects fork failed");
  84        dup2(pipe_fd[1], 1);
  85        close(pipe_fd[0]);
  86        close(pipe_fd[1]);
  87        close(fd);
  88        exec_rev_list(refs);
  89}
  90
  91static int pack_objects(int fd, struct ref *refs)
  92{
  93        pid_t rev_list_pid;
  94
  95        rev_list_pid = fork();
  96        if (!rev_list_pid) {
  97                rev_list(fd, refs);
  98                die("rev-list setup failed");
  99        }
 100        if (rev_list_pid < 0)
 101                die("rev-list fork failed");
 102        /*
 103         * We don't wait for the rev-list pipeline in the parent:
 104         * we end up waiting for the other end instead
 105         */
 106        return 0;
 107}
 108
 109static int read_ref(const char *ref, unsigned char *sha1)
 110{
 111        int fd, ret;
 112        char buffer[60];
 113
 114        fd = open(git_path("%s", ref), O_RDONLY);
 115        if (fd < 0)
 116                return -1;
 117        ret = -1;
 118        if (read(fd, buffer, sizeof(buffer)) >= 40)
 119                ret = get_sha1_hex(buffer, sha1);
 120        close(fd);
 121        return ret;
 122}
 123
 124static int ref_newer(const unsigned char *new_sha1, const unsigned char *old_sha1)
 125{
 126        if (!has_sha1_file(old_sha1))
 127                return 0;
 128        /*
 129         * FIXME! It is not correct to say that the new one is newer
 130         * just because we don't have the old one!
 131         *
 132         * We should really see if we can reach the old_sha1 commit
 133         * from the new_sha1 one.
 134         */
 135        return 1;
 136}
 137
 138static int local_ref_nr_match;
 139static char **local_ref_match;
 140static struct ref **local_ref_list;
 141
 142static int try_to_match(const char *refname, const unsigned char *sha1)
 143{
 144        struct ref *ref;
 145        int len;
 146
 147        if (!path_match(refname, local_ref_nr_match, local_ref_match))
 148                return 0;
 149
 150        len = strlen(refname)+1;
 151        ref = xmalloc(sizeof(*ref) + len);
 152        memset(ref->old_sha1, 0, 20);
 153        memcpy(ref->new_sha1, sha1, 20);
 154        memcpy(ref->name, refname, len);
 155        ref->next = NULL;
 156        *local_ref_list = ref;
 157        local_ref_list = &ref->next;
 158        return 0;
 159}
 160
 161static int send_pack(int in, int out, int nr_match, char **match)
 162{
 163        struct ref *ref_list = NULL, **last_ref = &ref_list;
 164        struct ref *ref;
 165        int new_refs;
 166
 167        /*
 168         * Read all the refs from the other end
 169         */
 170        for (;;) {
 171                unsigned char old_sha1[20];
 172                static char buffer[1000];
 173                char *name;
 174                int len;
 175
 176                len = packet_read_line(in, buffer, sizeof(buffer));
 177                if (!len)
 178                        break;
 179                if (buffer[len-1] == '\n')
 180                        buffer[--len] = 0;
 181
 182                if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
 183                        die("protocol error: expected sha/ref, got '%s'", buffer);
 184                name = buffer + 41;
 185                ref = xmalloc(sizeof(*ref) + len - 40);
 186                memcpy(ref->old_sha1, old_sha1, 20);
 187                memset(ref->new_sha1, 0, 20);
 188                memcpy(ref->name, buffer + 41, len - 40);
 189                ref->next = NULL;
 190                *last_ref = ref;
 191                last_ref = &ref->next;
 192        }
 193
 194        /*
 195         * Go through the refs, see if we want to update
 196         * any of them..
 197         */
 198        for (ref = ref_list; ref; ref = ref->next) {
 199                unsigned char new_sha1[20];
 200                char *name = ref->name;
 201
 202                if (nr_match && !path_match(name, nr_match, match))
 203                        continue;
 204
 205                if (read_ref(name, new_sha1) < 0)
 206                        continue;
 207
 208                if (!memcmp(ref->old_sha1, new_sha1, 20)) {
 209                        fprintf(stderr, "'%s' unchanged\n", name);
 210                        continue;
 211                }
 212
 213                if (!ref_newer(new_sha1, ref->old_sha1)) {
 214                        error("remote '%s' points to object I don't have", name);
 215                        continue;
 216                }
 217
 218                /* Ok, mark it for update */
 219                memcpy(ref->new_sha1, new_sha1, 20);
 220        }
 221
 222        /*
 223         * See if we have any refs that the other end didn't have
 224         */
 225        if (nr_match) {
 226                local_ref_nr_match = nr_match;
 227                local_ref_match = match;
 228                local_ref_list = last_ref;
 229                for_each_ref(try_to_match);
 230        }
 231
 232        /*
 233         * Finally, tell the other end!
 234         */
 235        new_refs = 0;
 236        for (ref = ref_list; ref; ref = ref->next) {
 237                char old_hex[60], *new_hex;
 238                if (is_zero_sha1(ref->new_sha1))
 239                        continue;
 240                new_refs++;
 241                strcpy(old_hex, sha1_to_hex(ref->old_sha1));
 242                new_hex = sha1_to_hex(ref->new_sha1);
 243                packet_write(out, "%s %s %s", old_hex, new_hex, ref->name);
 244                fprintf(stderr, "'%s': updating from %s to %s\n", ref->name, old_hex, new_hex);
 245        }
 246        
 247        packet_flush(out);
 248        if (new_refs)
 249                pack_objects(out, ref_list);
 250        close(out);
 251        return 0;
 252}
 253
 254int main(int argc, char **argv)
 255{
 256        int i, nr_heads = 0;
 257        char *dest = NULL;
 258        char **heads = NULL;
 259        int fd[2], ret;
 260        pid_t pid;
 261
 262        argv++;
 263        for (i = 1; i < argc; i++) {
 264                char *arg = *argv++;
 265
 266                if (*arg == '-') {
 267                        if (!strncmp(arg, "--exec=", 7)) {
 268                                exec = arg + 7;
 269                                continue;
 270                        }
 271                        usage(send_pack_usage);
 272                }
 273                dest = arg;
 274                heads = argv;
 275                nr_heads = argc - i -1;
 276                break;
 277        }
 278        if (!dest)
 279                usage(send_pack_usage);
 280        pid = git_connect(fd, dest, exec);
 281        if (pid < 0)
 282                return 1;
 283        ret = send_pack(fd[0], fd[1], nr_heads, heads);
 284        close(fd[0]);
 285        close(fd[1]);
 286        finish_connect(pid);
 287        return ret;
 288}