Andrew's git - gitweb.git/blob

   1#include "builtin.h"
   2#include "cache.h"
   3#include "object.h"
   4#include "commit.h"
   5#include "diff.h"
   6#include "revision.h"
   7#include "list-objects.h"
   8#include "run-command.h"
   9
  10/*
  11 * Basic handler for bundle files to connect repositories via sneakernet.
  12 * Invocation must include action.
  13 * This function can create a bundle or provide information on an existing
  14 * bundle supporting git-fetch, git-pull, and git-ls-remote
  15 */
  16
  17static const char *bundle_usage="git-bundle (create <bundle> <git-rev-list args> | verify <bundle> | list-heads <bundle> [refname]... | unbundle <bundle> [refname]... )";
  18
  19static const char bundle_signature[] = "# v2 git bundle\n";
  20
  21struct ref_list {
  22        unsigned int nr, alloc;
  23        struct ref_list_entry {
  24                unsigned char sha1[20];
  25                char *name;
  26        } *list;
  27};
  28
  29static void add_to_ref_list(const unsigned char *sha1, const char *name,
  30                struct ref_list *list)
  31{
  32        if (list->nr + 1 >= list->alloc) {
  33                list->alloc = alloc_nr(list->nr + 1);
  34                list->list = xrealloc(list->list,
  35                                list->alloc * sizeof(list->list[0]));
  36        }
  37        memcpy(list->list[list->nr].sha1, sha1, 20);
  38        list->list[list->nr].name = xstrdup(name);
  39        list->nr++;
  40}
  41
  42struct bundle_header {
  43        struct ref_list prerequisites;
  44        struct ref_list references;
  45};
  46
  47/* this function returns the length of the string */
  48static int read_string(int fd, char *buffer, int size)
  49{
  50        int i;
  51        for (i = 0; i < size - 1; i++) {
  52                ssize_t count = xread(fd, buffer + i, 1);
  53                if (count < 0)
  54                        return error("Read error: %s", strerror(errno));
  55                if (count == 0) {
  56                        i--;
  57                        break;
  58                }
  59                if (buffer[i] == '\n')
  60                        break;
  61        }
  62        buffer[i + 1] = '\0';
  63        return i + 1;
  64}
  65
  66/* returns an fd */
  67static int read_header(const char *path, struct bundle_header *header) {
  68        char buffer[1024];
  69        int fd = open(path, O_RDONLY);
  70
  71        if (fd < 0)
  72                return error("could not open '%s'", path);
  73        if (read_string(fd, buffer, sizeof(buffer)) < 0 ||
  74                        strcmp(buffer, bundle_signature)) {
  75                close(fd);
  76                return error("'%s' does not look like a v2 bundle file", path);
  77        }
  78        while (read_string(fd, buffer, sizeof(buffer)) > 0
  79                        && buffer[0] != '\n') {
  80                int is_prereq = buffer[0] == '-';
  81                int offset = is_prereq ? 1 : 0;
  82                int len = strlen(buffer);
  83                unsigned char sha1[20];
  84                struct ref_list *list = is_prereq ? &header->prerequisites
  85                        : &header->references;
  86                char delim;
  87
  88                if (buffer[len - 1] == '\n')
  89                        buffer[len - 1] = '\0';
  90                if (get_sha1_hex(buffer + offset, sha1)) {
  91                        warning("unrecognized header: %s", buffer);
  92                        continue;
  93                }
  94                delim = buffer[40 + offset];
  95                if (!isspace(delim) && (delim != '\0' || !is_prereq))
  96                        die ("invalid header: %s", buffer);
  97                add_to_ref_list(sha1, isspace(delim) ?
  98                                buffer + 41 + offset : "", list);
  99        }
 100        return fd;
 101}
 102
 103static int list_refs(struct ref_list *r, int argc, const char **argv)
 104{
 105        int i;
 106
 107        for (i = 0; i < r->nr; i++) {
 108                if (argc > 1) {
 109                        int j;
 110                        for (j = 1; j < argc; j++)
 111                                if (!strcmp(r->list[i].name, argv[j]))
 112                                        break;
 113                        if (j == argc)
 114                                continue;
 115                }
 116                printf("%s %s\n", sha1_to_hex(r->list[i].sha1),
 117                                r->list[i].name);
 118        }
 119        return 0;
 120}
 121
 122#define PREREQ_MARK (1u<<16)
 123
 124static int verify_bundle(struct bundle_header *header, int verbose)
 125{
 126        /*
 127         * Do fast check, then if any prereqs are missing then go line by line
 128         * to be verbose about the errors
 129         */
 130        struct ref_list *p = &header->prerequisites;
 131        struct rev_info revs;
 132        const char *argv[] = {NULL, "--all"};
 133        struct object_array refs;
 134        struct commit *commit;
 135        int i, ret = 0, req_nr;
 136        const char *message = "Repository lacks these prerequisite commits:";
 137
 138        init_revisions(&revs, NULL);
 139        for (i = 0; i < p->nr; i++) {
 140                struct ref_list_entry *e = p->list + i;
 141                struct object *o = parse_object(e->sha1);
 142                if (o) {
 143                        o->flags |= PREREQ_MARK;
 144                        add_pending_object(&revs, o, e->name);
 145                        continue;
 146                }
 147                if (++ret == 1)
 148                        error(message);
 149                error("%s %s", sha1_to_hex(e->sha1), e->name);
 150        }
 151        if (revs.pending.nr != p->nr)
 152                return ret;
 153        req_nr = revs.pending.nr;
 154        setup_revisions(2, argv, &revs, NULL);
 155
 156        memset(&refs, 0, sizeof(struct object_array));
 157        for (i = 0; i < revs.pending.nr; i++) {
 158                struct object_array_entry *e = revs.pending.objects + i;
 159                add_object_array(e->item, e->name, &refs);
 160        }
 161
 162        prepare_revision_walk(&revs);
 163
 164        i = req_nr;
 165        while (i && (commit = get_revision(&revs)))
 166                if (commit->object.flags & PREREQ_MARK)
 167                        i--;
 168
 169        for (i = 0; i < req_nr; i++)
 170                if (!(refs.objects[i].item->flags & SHOWN)) {
 171                        if (++ret == 1)
 172                                error(message);
 173                        error("%s %s", sha1_to_hex(refs.objects[i].item->sha1),
 174                                refs.objects[i].name);
 175                }
 176
 177        for (i = 0; i < refs.nr; i++)
 178                clear_commit_marks((struct commit *)refs.objects[i].item, -1);
 179
 180        if (verbose) {
 181                struct ref_list *r;
 182
 183                r = &header->references;
 184                printf("The bundle contains %d ref%s\n",
 185                       r->nr, (1 < r->nr) ? "s" : "");
 186                list_refs(r, 0, NULL);
 187                r = &header->prerequisites;
 188                printf("The bundle requires these %d ref%s\n",
 189                       r->nr, (1 < r->nr) ? "s" : "");
 190                list_refs(r, 0, NULL);
 191        }
 192        return ret;
 193}
 194
 195static int list_heads(struct bundle_header *header, int argc, const char **argv)
 196{
 197        return list_refs(&header->references, argc, argv);
 198}
 199
 200static int create_bundle(struct bundle_header *header, const char *path,
 201                int argc, const char **argv)
 202{
 203        int bundle_fd = -1;
 204        const char **argv_boundary = xmalloc((argc + 4) * sizeof(const char *));
 205        const char **argv_pack = xmalloc(5 * sizeof(const char *));
 206        int i, ref_count = 0;
 207        char buffer[1024];
 208        struct rev_info revs;
 209        struct child_process rls;
 210
 211        bundle_fd = (!strcmp(path, "-") ? 1 :
 212                        open(path, O_CREAT | O_EXCL | O_WRONLY, 0666));
 213        if (bundle_fd < 0)
 214                return error("Could not create '%s': %s", path, strerror(errno));
 215
 216        /* write signature */
 217        write_or_die(bundle_fd, bundle_signature, strlen(bundle_signature));
 218
 219        /* init revs to list objects for pack-objects later */
 220        save_commit_buffer = 0;
 221        init_revisions(&revs, NULL);
 222
 223        /* write prerequisites */
 224        memcpy(argv_boundary + 3, argv + 1, argc * sizeof(const char *));
 225        argv_boundary[0] = "rev-list";
 226        argv_boundary[1] = "--boundary";
 227        argv_boundary[2] = "--pretty=oneline";
 228        argv_boundary[argc + 2] = NULL;
 229        memset(&rls, 0, sizeof(rls));
 230        rls.argv = argv_boundary;
 231        rls.out = -1;
 232        rls.git_cmd = 1;
 233        if (start_command(&rls))
 234                return -1;
 235        while ((i = read_string(rls.out, buffer, sizeof(buffer))) > 0) {
 236                unsigned char sha1[20];
 237                if (buffer[0] == '-') {
 238                        write_or_die(bundle_fd, buffer, i);
 239                        if (!get_sha1_hex(buffer + 1, sha1)) {
 240                                struct object *object = parse_object(sha1);
 241                                object->flags |= UNINTERESTING;
 242                                add_pending_object(&revs, object, buffer);
 243                        }
 244                } else if (!get_sha1_hex(buffer, sha1)) {
 245                        struct object *object = parse_object(sha1);
 246                        object->flags |= SHOWN;
 247                }
 248        }
 249        if (finish_command(&rls))
 250                return error("rev-list died");
 251
 252        /* write references */
 253        argc = setup_revisions(argc, argv, &revs, NULL);
 254        if (argc > 1)
 255                return error("unrecognized argument: %s'", argv[1]);
 256
 257        for (i = 0; i < revs.pending.nr; i++) {
 258                struct object_array_entry *e = revs.pending.objects + i;
 259                unsigned char sha1[20];
 260                char *ref;
 261
 262                if (e->item->flags & UNINTERESTING)
 263                        continue;
 264                if (dwim_ref(e->name, strlen(e->name), sha1, &ref) != 1)
 265                        continue;
 266                /*
 267                 * Make sure the refs we wrote out is correct; --max-count and
 268                 * other limiting options could have prevented all the tips
 269                 * from getting output.
 270                 */
 271                if (!(e->item->flags & SHOWN)) {
 272                        warning("ref '%s' is excluded by the rev-list options",
 273                                e->name);
 274                        continue;
 275                }
 276                ref_count++;
 277                write_or_die(bundle_fd, sha1_to_hex(e->item->sha1), 40);
 278                write_or_die(bundle_fd, " ", 1);
 279                write_or_die(bundle_fd, ref, strlen(ref));
 280                write_or_die(bundle_fd, "\n", 1);
 281                free(ref);
 282        }
 283        if (!ref_count)
 284                die ("Refusing to create empty bundle.");
 285
 286        /* end header */
 287        write_or_die(bundle_fd, "\n", 1);
 288
 289        /* write pack */
 290        argv_pack[0] = "pack-objects";
 291        argv_pack[1] = "--all-progress";
 292        argv_pack[2] = "--stdout";
 293        argv_pack[3] = "--thin";
 294        argv_pack[4] = NULL;
 295        memset(&rls, 0, sizeof(rls));
 296        rls.argv = argv_pack;
 297        rls.in = -1;
 298        rls.out = bundle_fd;
 299        rls.git_cmd = 1;
 300        if (start_command(&rls))
 301                return error("Could not spawn pack-objects");
 302        for (i = 0; i < revs.pending.nr; i++) {
 303                struct object *object = revs.pending.objects[i].item;
 304                if (object->flags & UNINTERESTING)
 305                        write(rls.in, "^", 1);
 306                write(rls.in, sha1_to_hex(object->sha1), 40);
 307                write(rls.in, "\n", 1);
 308        }
 309        if (finish_command(&rls))
 310                return error ("pack-objects died");
 311        return 0;
 312}
 313
 314static int unbundle(struct bundle_header *header, int bundle_fd,
 315                int argc, const char **argv)
 316{
 317        const char *argv_index_pack[] = {"index-pack",
 318                "--fix-thin", "--stdin", NULL};
 319        struct child_process ip;
 320
 321        if (verify_bundle(header, 0))
 322                return -1;
 323        memset(&ip, 0, sizeof(ip));
 324        ip.argv = argv_index_pack;
 325        ip.in = bundle_fd;
 326        ip.no_stdout = 1;
 327        ip.git_cmd = 1;
 328        if (run_command(&ip))
 329                return error("index-pack died");
 330        return list_heads(header, argc, argv);
 331}
 332
 333int cmd_bundle(int argc, const char **argv, const char *prefix)
 334{
 335        struct bundle_header header;
 336        int nongit = 0;
 337        const char *cmd, *bundle_file;
 338        int bundle_fd = -1;
 339        char buffer[PATH_MAX];
 340
 341        if (argc < 3)
 342                usage(bundle_usage);
 343
 344        cmd = argv[1];
 345        bundle_file = argv[2];
 346        argc -= 2;
 347        argv += 2;
 348
 349        prefix = setup_git_directory_gently(&nongit);
 350        if (prefix && bundle_file[0] != '/') {
 351                snprintf(buffer, sizeof(buffer), "%s/%s", prefix, bundle_file);
 352                bundle_file = buffer;
 353        }
 354
 355        memset(&header, 0, sizeof(header));
 356        if (strcmp(cmd, "create") &&
 357                        (bundle_fd = read_header(bundle_file, &header)) < 0)
 358                return 1;
 359
 360        if (!strcmp(cmd, "verify")) {
 361                close(bundle_fd);
 362                if (verify_bundle(&header, 1))
 363                        return 1;
 364                fprintf(stderr, "%s is okay\n", bundle_file);
 365                return 0;
 366        }
 367        if (!strcmp(cmd, "list-heads")) {
 368                close(bundle_fd);
 369                return !!list_heads(&header, argc, argv);
 370        }
 371        if (!strcmp(cmd, "create")) {
 372                if (nongit)
 373                        die("Need a repository to create a bundle.");
 374                return !!create_bundle(&header, bundle_file, argc, argv);
 375        } else if (!strcmp(cmd, "unbundle")) {
 376                if (nongit)
 377                        die("Need a repository to unbundle.");
 378                return !!unbundle(&header, bundle_fd, argc, argv);
 379        } else
 380                usage(bundle_usage);
 381}