Andrew's git - gitweb.git/blob

   1#include "cache.h"
   2#include "object.h"
   3#include "commit.h"
   4#include "diff.h"
   5#include "revision.h"
   6#include "list-objects.h"
   7#include "run-command.h"
   8
   9/*
  10 * Basic handler for bundle files to connect repositories via sneakernet.
  11 * Invocation must include action.
  12 * This function can create a bundle or provide information on an existing
  13 * bundle supporting git-fetch, git-pull, and git-ls-remote
  14 */
  15
  16static const char *bundle_usage="git-bundle (create <bundle> <git-rev-list args> | verify <bundle> | list-heads <bundle> [refname]... | unbundle <bundle> [refname]... )";
  17
  18static const char bundle_signature[] = "# v2 git bundle\n";
  19
  20struct ref_list {
  21        unsigned int nr, alloc;
  22        struct ref_list_entry {
  23                unsigned char sha1[20];
  24                char *name;
  25        } *list;
  26};
  27
  28static void add_to_ref_list(const unsigned char *sha1, const char *name,
  29                struct ref_list *list)
  30{
  31        if (list->nr + 1 >= list->alloc) {
  32                list->alloc = alloc_nr(list->nr + 1);
  33                list->list = xrealloc(list->list,
  34                                list->alloc * sizeof(list->list[0]));
  35        }
  36        memcpy(list->list[list->nr].sha1, sha1, 20);
  37        list->list[list->nr].name = xstrdup(name);
  38        list->nr++;
  39}
  40
  41struct bundle_header {
  42        struct ref_list prerequisites;
  43        struct ref_list references;
  44};
  45
  46/* this function returns the length of the string */
  47static int read_string(int fd, char *buffer, int size)
  48{
  49        int i;
  50        for (i = 0; i < size - 1; i++) {
  51                ssize_t count = xread(fd, buffer + i, 1);
  52                if (count < 0)
  53                        return error("Read error: %s", strerror(errno));
  54                if (count == 0) {
  55                        i--;
  56                        break;
  57                }
  58                if (buffer[i] == '\n')
  59                        break;
  60        }
  61        buffer[i + 1] = '\0';
  62        return i + 1;
  63}
  64
  65/* returns an fd */
  66static int read_header(const char *path, struct bundle_header *header) {
  67        char buffer[1024];
  68        int fd = open(path, O_RDONLY);
  69
  70        if (fd < 0)
  71                return error("could not open '%s'", path);
  72        if (read_string(fd, buffer, sizeof(buffer)) < 0 ||
  73                        strcmp(buffer, bundle_signature)) {
  74                close(fd);
  75                return error("'%s' does not look like a v2 bundle file", path);
  76        }
  77        while (read_string(fd, buffer, sizeof(buffer)) > 0
  78                        && buffer[0] != '\n') {
  79                int is_prereq = buffer[0] == '-';
  80                int offset = is_prereq ? 1 : 0;
  81                int len = strlen(buffer);
  82                unsigned char sha1[20];
  83                struct ref_list *list = is_prereq ? &header->prerequisites
  84                        : &header->references;
  85                char delim;
  86
  87                if (buffer[len - 1] == '\n')
  88                        buffer[len - 1] = '\0';
  89                if (get_sha1_hex(buffer + offset, sha1)) {
  90                        warning("unrecognized header: %s", buffer);
  91                        continue;
  92                }
  93                delim = buffer[40 + offset];
  94                if (!isspace(delim) && (delim != '\0' || !is_prereq))
  95                        die ("invalid header: %s", buffer);
  96                add_to_ref_list(sha1, isspace(delim) ?
  97                                buffer + 41 + offset : "", list);
  98        }
  99        return fd;
 100}
 101
 102static int list_refs(struct ref_list *r, int argc, const char **argv)
 103{
 104        int i;
 105
 106        for (i = 0; i < r->nr; i++) {
 107                if (argc > 1) {
 108                        int j;
 109                        for (j = 1; j < argc; j++)
 110                                if (!strcmp(r->list[i].name, argv[j]))
 111                                        break;
 112                        if (j == argc)
 113                                continue;
 114                }
 115                printf("%s %s\n", sha1_to_hex(r->list[i].sha1),
 116                                r->list[i].name);
 117        }
 118        return 0;
 119}
 120
 121#define PREREQ_MARK (1u<<16)
 122
 123static int verify_bundle(struct bundle_header *header, int verbose)
 124{
 125        /*
 126         * Do fast check, then if any prereqs are missing then go line by line
 127         * to be verbose about the errors
 128         */
 129        struct ref_list *p = &header->prerequisites;
 130        struct rev_info revs;
 131        const char *argv[] = {NULL, "--all"};
 132        struct object_array refs;
 133        struct commit *commit;
 134        int i, ret = 0, req_nr;
 135        const char *message = "Repository lacks these prerequisite commits:";
 136
 137        init_revisions(&revs, NULL);
 138        for (i = 0; i < p->nr; i++) {
 139                struct ref_list_entry *e = p->list + i;
 140                struct object *o = parse_object(e->sha1);
 141                if (o) {
 142                        o->flags |= PREREQ_MARK;
 143                        add_pending_object(&revs, o, e->name);
 144                        continue;
 145                }
 146                if (++ret == 1)
 147                        error(message);
 148                error("%s %s", sha1_to_hex(e->sha1), e->name);
 149        }
 150        if (revs.pending.nr != p->nr)
 151                return ret;
 152        req_nr = revs.pending.nr;
 153        setup_revisions(2, argv, &revs, NULL);
 154
 155        memset(&refs, 0, sizeof(struct object_array));
 156        for (i = 0; i < revs.pending.nr; i++) {
 157                struct object_array_entry *e = revs.pending.objects + i;
 158                add_object_array(e->item, e->name, &refs);
 159        }
 160
 161        prepare_revision_walk(&revs);
 162
 163        i = req_nr;
 164        while (i && (commit = get_revision(&revs)))
 165                if (commit->object.flags & PREREQ_MARK)
 166                        i--;
 167
 168        for (i = 0; i < req_nr; i++)
 169                if (!(refs.objects[i].item->flags & SHOWN)) {
 170                        if (++ret == 1)
 171                                error(message);
 172                        error("%s %s", sha1_to_hex(refs.objects[i].item->sha1),
 173                                refs.objects[i].name);
 174                }
 175
 176        for (i = 0; i < refs.nr; i++)
 177                clear_commit_marks((struct commit *)refs.objects[i].item, -1);
 178
 179        if (verbose) {
 180                struct ref_list *r;
 181
 182                r = &header->references;
 183                printf("The bundle contains %d ref%s\n",
 184                       r->nr, (1 < r->nr) ? "s" : "");
 185                list_refs(r, 0, NULL);
 186                r = &header->prerequisites;
 187                printf("The bundle requires these %d ref%s\n",
 188                       r->nr, (1 < r->nr) ? "s" : "");
 189                list_refs(r, 0, NULL);
 190        }
 191        return ret;
 192}
 193
 194static int list_heads(struct bundle_header *header, int argc, const char **argv)
 195{
 196        return list_refs(&header->references, argc, argv);
 197}
 198
 199static int create_bundle(struct bundle_header *header, const char *path,
 200                int argc, const char **argv)
 201{
 202        int bundle_fd = -1;
 203        const char **argv_boundary = xmalloc((argc + 4) * sizeof(const char *));
 204        const char **argv_pack = xmalloc(5 * sizeof(const char *));
 205        int i, ref_count = 0;
 206        char buffer[1024];
 207        struct rev_info revs;
 208        struct child_process rls;
 209
 210        bundle_fd = (!strcmp(path, "-") ? 1 :
 211                        open(path, O_CREAT | O_EXCL | O_WRONLY, 0666));
 212        if (bundle_fd < 0)
 213                return error("Could not create '%s': %s", path, strerror(errno));
 214
 215        /* write signature */
 216        write_or_die(bundle_fd, bundle_signature, strlen(bundle_signature));
 217
 218        /* init revs to list objects for pack-objects later */
 219        save_commit_buffer = 0;
 220        init_revisions(&revs, NULL);
 221
 222        /* write prerequisites */
 223        memcpy(argv_boundary + 3, argv + 1, argc * sizeof(const char *));
 224        argv_boundary[0] = "rev-list";
 225        argv_boundary[1] = "--boundary";
 226        argv_boundary[2] = "--pretty=oneline";
 227        argv_boundary[argc + 2] = NULL;
 228        memset(&rls, 0, sizeof(rls));
 229        rls.argv = argv_boundary;
 230        rls.out = -1;
 231        rls.git_cmd = 1;
 232        if (start_command(&rls))
 233                return -1;
 234        while ((i = read_string(rls.out, buffer, sizeof(buffer))) > 0) {
 235                unsigned char sha1[20];
 236                if (buffer[0] == '-') {
 237                        write_or_die(bundle_fd, buffer, i);
 238                        if (!get_sha1_hex(buffer + 1, sha1)) {
 239                                struct object *object = parse_object(sha1);
 240                                object->flags |= UNINTERESTING;
 241                                add_pending_object(&revs, object, buffer);
 242                        }
 243                } else if (!get_sha1_hex(buffer, sha1)) {
 244                        struct object *object = parse_object(sha1);
 245                        object->flags |= SHOWN;
 246                }
 247        }
 248        if (finish_command(&rls))
 249                return error("rev-list died");
 250
 251        /* write references */
 252        argc = setup_revisions(argc, argv, &revs, NULL);
 253        if (argc > 1)
 254                return error("unrecognized argument: %s'", argv[1]);
 255
 256        for (i = 0; i < revs.pending.nr; i++) {
 257                struct object_array_entry *e = revs.pending.objects + i;
 258                unsigned char sha1[20];
 259                char *ref;
 260
 261                if (e->item->flags & UNINTERESTING)
 262                        continue;
 263                if (dwim_ref(e->name, strlen(e->name), sha1, &ref) != 1)
 264                        continue;
 265                /*
 266                 * Make sure the refs we wrote out is correct; --max-count and
 267                 * other limiting options could have prevented all the tips
 268                 * from getting output.
 269                 */
 270                if (!(e->item->flags & SHOWN)) {
 271                        warning("ref '%s' is excluded by the rev-list options",
 272                                e->name);
 273                        continue;
 274                }
 275                ref_count++;
 276                write_or_die(bundle_fd, sha1_to_hex(e->item->sha1), 40);
 277                write_or_die(bundle_fd, " ", 1);
 278                write_or_die(bundle_fd, ref, strlen(ref));
 279                write_or_die(bundle_fd, "\n", 1);
 280                free(ref);
 281        }
 282        if (!ref_count)
 283                die ("Refusing to create empty bundle.");
 284
 285        /* end header */
 286        write_or_die(bundle_fd, "\n", 1);
 287
 288        /* write pack */
 289        argv_pack[0] = "pack-objects";
 290        argv_pack[1] = "--all-progress";
 291        argv_pack[2] = "--stdout";
 292        argv_pack[3] = "--thin";
 293        argv_pack[4] = NULL;
 294        memset(&rls, 0, sizeof(rls));
 295        rls.argv = argv_pack;
 296        rls.in = -1;
 297        rls.out = bundle_fd;
 298        rls.git_cmd = 1;
 299        if (start_command(&rls))
 300                return error("Could not spawn pack-objects");
 301        for (i = 0; i < revs.pending.nr; i++) {
 302                struct object *object = revs.pending.objects[i].item;
 303                if (object->flags & UNINTERESTING)
 304                        write(rls.in, "^", 1);
 305                write(rls.in, sha1_to_hex(object->sha1), 40);
 306                write(rls.in, "\n", 1);
 307        }
 308        if (finish_command(&rls))
 309                return error ("pack-objects died");
 310        return 0;
 311}
 312
 313static int unbundle(struct bundle_header *header, int bundle_fd,
 314                int argc, const char **argv)
 315{
 316        const char *argv_index_pack[] = {"index-pack",
 317                "--fix-thin", "--stdin", NULL};
 318        struct child_process ip;
 319
 320        if (verify_bundle(header, 0))
 321                return -1;
 322        memset(&ip, 0, sizeof(ip));
 323        ip.argv = argv_index_pack;
 324        ip.in = bundle_fd;
 325        ip.no_stdout = 1;
 326        ip.git_cmd = 1;
 327        if (run_command(&ip))
 328                return error("index-pack died");
 329        return list_heads(header, argc, argv);
 330}
 331
 332int cmd_bundle(int argc, const char **argv, const char *prefix)
 333{
 334        struct bundle_header header;
 335        int nongit = 0;
 336        const char *cmd, *bundle_file;
 337        int bundle_fd = -1;
 338        char buffer[PATH_MAX];
 339
 340        if (argc < 3)
 341                usage(bundle_usage);
 342
 343        cmd = argv[1];
 344        bundle_file = argv[2];
 345        argc -= 2;
 346        argv += 2;
 347
 348        prefix = setup_git_directory_gently(&nongit);
 349        if (prefix && bundle_file[0] != '/') {
 350                snprintf(buffer, sizeof(buffer), "%s/%s", prefix, bundle_file);
 351                bundle_file = buffer;
 352        }
 353
 354        memset(&header, 0, sizeof(header));
 355        if (strcmp(cmd, "create") &&
 356                        (bundle_fd = read_header(bundle_file, &header)) < 0)
 357                return 1;
 358
 359        if (!strcmp(cmd, "verify")) {
 360                close(bundle_fd);
 361                if (verify_bundle(&header, 1))
 362                        return 1;
 363                fprintf(stderr, "%s is okay\n", bundle_file);
 364                return 0;
 365        }
 366        if (!strcmp(cmd, "list-heads")) {
 367                close(bundle_fd);
 368                return !!list_heads(&header, argc, argv);
 369        }
 370        if (!strcmp(cmd, "create")) {
 371                if (nongit)
 372                        die("Need a repository to create a bundle.");
 373                return !!create_bundle(&header, bundle_file, argc, argv);
 374        } else if (!strcmp(cmd, "unbundle")) {
 375                if (nongit)
 376                        die("Need a repository to unbundle.");
 377                return !!unbundle(&header, bundle_fd, argc, argv);
 378        } else
 379                usage(bundle_usage);
 380}