Andrew's git - gitweb.git/blob

   1#include "cache.h"
   2#include "refs.h"
   3#include "pkt-line.h"
   4#include "tag.h"
   5#include "object.h"
   6#include "commit.h"
   7
   8static const char upload_pack_usage[] = "git-upload-pack [--strict] [--timeout=nn] <dir>";
   9
  10#define THEY_HAVE (1U << 0)
  11#define OUR_REF (1U << 1)
  12#define WANTED (1U << 2)
  13#define MAX_HAS 256
  14#define MAX_NEEDS 256
  15static int nr_has = 0, nr_needs = 0, multi_ack = 0, nr_our_refs = 0;
  16static unsigned char has_sha1[MAX_HAS][20];
  17static unsigned char needs_sha1[MAX_NEEDS][20];
  18static unsigned int timeout = 0;
  19
  20static void reset_timeout(void)
  21{
  22        alarm(timeout);
  23}
  24
  25static int strip(char *line, int len)
  26{
  27        if (len && line[len-1] == '\n')
  28                line[--len] = 0;
  29        return len;
  30}
  31
  32static void create_pack_file(void)
  33{
  34        int fd[2];
  35        pid_t pid;
  36        int create_full_pack = (nr_our_refs == nr_needs && !nr_has);
  37
  38        if (pipe(fd) < 0)
  39                die("git-upload-pack: unable to create pipe");
  40        pid = fork();
  41        if (pid < 0)
  42                die("git-upload-pack: unable to fork git-rev-list");
  43
  44        if (!pid) {
  45                int i;
  46                int args;
  47                char **argv;
  48                char *buf;
  49                char **p;
  50
  51                if (create_full_pack)
  52                        args = 10;
  53                else
  54                        args = nr_has + nr_needs + 5;
  55                argv = xmalloc(args * sizeof(char *));
  56                buf = xmalloc(args * 45);
  57                p = argv;
  58
  59                dup2(fd[1], 1);
  60                close(0);
  61                close(fd[0]);
  62                close(fd[1]);
  63                *p++ = "git-rev-list";
  64                *p++ = "--objects";
  65                if (create_full_pack || MAX_NEEDS <= nr_needs)
  66                        *p++ = "--all";
  67                else {
  68                        for (i = 0; i < nr_needs; i++) {
  69                                *p++ = buf;
  70                                memcpy(buf, sha1_to_hex(needs_sha1[i]), 41);
  71                                buf += 41;
  72                        }
  73                }
  74                if (!create_full_pack)
  75                        for (i = 0; i < nr_has; i++) {
  76                                *p++ = buf;
  77                                *buf++ = '^';
  78                                memcpy(buf, sha1_to_hex(has_sha1[i]), 41);
  79                                buf += 41;
  80                        }
  81                *p++ = NULL;
  82                execvp("git-rev-list", argv);
  83                die("git-upload-pack: unable to exec git-rev-list");
  84        }
  85        dup2(fd[0], 0);
  86        close(fd[0]);
  87        close(fd[1]);
  88        execlp("git-pack-objects", "git-pack-objects", "--stdout", NULL);
  89        die("git-upload-pack: unable to exec git-pack-objects");
  90}
  91
  92static int got_sha1(char *hex, unsigned char *sha1)
  93{
  94        if (get_sha1_hex(hex, sha1))
  95                die("git-upload-pack: expected SHA1 object, got '%s'", hex);
  96        if (!has_sha1_file(sha1))
  97                return 0;
  98        if (nr_has < MAX_HAS) {
  99                struct object *o = lookup_object(sha1);
 100                if (!(o && o->parsed))
 101                        o = parse_object(sha1);
 102                if (!o)
 103                        die("oops (%s)", sha1_to_hex(sha1));
 104                if (o->type == commit_type) {
 105                        struct commit_list *parents;
 106                        if (o->flags & THEY_HAVE)
 107                                return 0;
 108                        o->flags |= THEY_HAVE;
 109                        for (parents = ((struct commit*)o)->parents;
 110                             parents;
 111                             parents = parents->next)
 112                                parents->item->object.flags |= THEY_HAVE;
 113                }
 114                memcpy(has_sha1[nr_has++], sha1, 20);
 115        }
 116        return 1;
 117}
 118
 119static int get_common_commits(void)
 120{
 121        static char line[1000];
 122        unsigned char sha1[20], last_sha1[20];
 123        int len;
 124
 125        track_object_refs = 0;
 126        save_commit_buffer = 0;
 127
 128        for(;;) {
 129                len = packet_read_line(0, line, sizeof(line));
 130                reset_timeout();
 131
 132                if (!len) {
 133                        if (nr_has == 0 || multi_ack)
 134                                packet_write(1, "NAK\n");
 135                        continue;
 136                }
 137                len = strip(line, len);
 138                if (!strncmp(line, "have ", 5)) {
 139                        if (got_sha1(line+5, sha1) &&
 140                                        (multi_ack || nr_has == 1)) {
 141                                if (nr_has >= MAX_HAS)
 142                                        multi_ack = 0;
 143                                packet_write(1, "ACK %s%s\n",
 144                                        sha1_to_hex(sha1),
 145                                        multi_ack ?  " continue" : "");
 146                                if (multi_ack)
 147                                        memcpy(last_sha1, sha1, 20);
 148                        }
 149                        continue;
 150                }
 151                if (!strcmp(line, "done")) {
 152                        if (nr_has > 0) {
 153                                if (multi_ack)
 154                                        packet_write(1, "ACK %s\n",
 155                                                        sha1_to_hex(last_sha1));
 156                                return 0;
 157                        }
 158                        packet_write(1, "NAK\n");
 159                        return -1;
 160                }
 161                die("git-upload-pack: expected SHA1 list, got '%s'", line);
 162        }
 163}
 164
 165static int receive_needs(void)
 166{
 167        static char line[1000];
 168        int len, needs;
 169
 170        needs = 0;
 171        for (;;) {
 172                struct object *o;
 173                unsigned char dummy[20], *sha1_buf;
 174                len = packet_read_line(0, line, sizeof(line));
 175                reset_timeout();
 176                if (!len)
 177                        return needs;
 178
 179                sha1_buf = dummy;
 180                if (needs == MAX_NEEDS) {
 181                        fprintf(stderr,
 182                                "warning: supporting only a max of %d requests. "
 183                                "sending everything instead.\n",
 184                                MAX_NEEDS);
 185                }
 186                else if (needs < MAX_NEEDS)
 187                        sha1_buf = needs_sha1[needs];
 188
 189                if (strncmp("want ", line, 5) || get_sha1_hex(line+5, sha1_buf))
 190                        die("git-upload-pack: protocol error, "
 191                            "expected to get sha, not '%s'", line);
 192                if (strstr(line+45, "multi_ack"))
 193                        multi_ack = 1;
 194
 195                /* We have sent all our refs already, and the other end
 196                 * should have chosen out of them; otherwise they are
 197                 * asking for nonsense.
 198                 *
 199                 * Hmph.  We may later want to allow "want" line that
 200                 * asks for something like "master~10" (symbolic)...
 201                 * would it make sense?  I don't know.
 202                 */
 203                o = lookup_object(sha1_buf);
 204                if (!o || !(o->flags & OUR_REF))
 205                        die("git-upload-pack: not our ref %s", line+5);
 206                if (!(o->flags & WANTED)) {
 207                        o->flags |= WANTED;
 208                        needs++;
 209                }
 210        }
 211}
 212
 213static int send_ref(const char *refname, const unsigned char *sha1)
 214{
 215        static char *capabilities = "multi_ack";
 216        struct object *o = parse_object(sha1);
 217
 218        if (capabilities)
 219                packet_write(1, "%s %s%c%s\n", sha1_to_hex(sha1), refname,
 220                        0, capabilities);
 221        else
 222                packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname);
 223        capabilities = NULL;
 224        if (!(o->flags & OUR_REF)) {
 225                o->flags |= OUR_REF;
 226                nr_our_refs++;
 227        }
 228        if (o->type == tag_type) {
 229                o = deref_tag(o, refname, 0);
 230                packet_write(1, "%s %s^{}\n", sha1_to_hex(o->sha1), refname);
 231        }
 232        return 0;
 233}
 234
 235static int upload_pack(void)
 236{
 237        reset_timeout();
 238        head_ref(send_ref);
 239        for_each_ref(send_ref);
 240        packet_flush(1);
 241        nr_needs = receive_needs();
 242        if (!nr_needs)
 243                return 0;
 244        get_common_commits();
 245        create_pack_file();
 246        return 0;
 247}
 248
 249int main(int argc, char **argv)
 250{
 251        const char *dir;
 252        int i;
 253        int strict = 0;
 254
 255        for (i = 1; i < argc; i++) {
 256                char *arg = argv[i];
 257
 258                if (arg[0] != '-')
 259                        break;
 260                if (!strcmp(arg, "--strict")) {
 261                        strict = 1;
 262                        continue;
 263                }
 264                if (!strncmp(arg, "--timeout=", 10)) {
 265                        timeout = atoi(arg+10);
 266                        continue;
 267                }
 268                if (!strcmp(arg, "--")) {
 269                        i++;
 270                        break;
 271                }
 272        }
 273        
 274        if (i != argc-1)
 275                usage(upload_pack_usage);
 276        dir = argv[i];
 277
 278        /* chdir to the directory. If that fails, try appending ".git" */
 279        if (chdir(dir) < 0) {
 280                if (strict || chdir(mkpath("%s.git", dir)) < 0)
 281                        die("git-upload-pack unable to chdir to %s", dir);
 282        }
 283        if (!strict)
 284                chdir(".git");
 285
 286        if (access("objects", X_OK) || access("refs", X_OK))
 287                die("git-upload-pack: %s doesn't seem to be a git archive", dir);
 288
 289        putenv("GIT_DIR=.");
 290        upload_pack();
 291        return 0;
 292}