Andrew's git - gitweb.git/blob

   1#include "cache.h"
   2#include "commit.h"
   3#include "tag.h"
   4#include "pkt-line.h"
   5#include "remote.h"
   6#include "refs.h"
   7#include "sha1-array.h"
   8#include "diff.h"
   9#include "revision.h"
  10#include "commit-slab.h"
  11
  12static int is_shallow = -1;
  13static struct stat shallow_stat;
  14static char *alternate_shallow_file;
  15
  16void set_alternate_shallow_file(const char *path)
  17{
  18        if (is_shallow != -1)
  19                die("BUG: is_repository_shallow must not be called before set_alternate_shallow_file");
  20        free(alternate_shallow_file);
  21        alternate_shallow_file = path ? xstrdup(path) : NULL;
  22}
  23
  24int register_shallow(const unsigned char *sha1)
  25{
  26        struct commit_graft *graft =
  27                xmalloc(sizeof(struct commit_graft));
  28        struct commit *commit = lookup_commit(sha1);
  29
  30        hashcpy(graft->sha1, sha1);
  31        graft->nr_parent = -1;
  32        if (commit && commit->object.parsed)
  33                commit->parents = NULL;
  34        return register_commit_graft(graft, 0);
  35}
  36
  37int is_repository_shallow(void)
  38{
  39        FILE *fp;
  40        char buf[1024];
  41        const char *path = alternate_shallow_file;
  42
  43        if (is_shallow >= 0)
  44                return is_shallow;
  45
  46        if (!path)
  47                path = git_path("shallow");
  48        /*
  49         * fetch-pack sets '--shallow-file ""' as an indicator that no
  50         * shallow file should be used. We could just open it and it
  51         * will likely fail. But let's do an explicit check instead.
  52         */
  53        if (!*path ||
  54            stat(path, &shallow_stat) ||
  55            (fp = fopen(path, "r")) == NULL) {
  56                is_shallow = 0;
  57                return is_shallow;
  58        }
  59        is_shallow = 1;
  60
  61        while (fgets(buf, sizeof(buf), fp)) {
  62                unsigned char sha1[20];
  63                if (get_sha1_hex(buf, sha1))
  64                        die("bad shallow line: %s", buf);
  65                register_shallow(sha1);
  66        }
  67        fclose(fp);
  68        return is_shallow;
  69}
  70
  71struct commit_list *get_shallow_commits(struct object_array *heads, int depth,
  72                int shallow_flag, int not_shallow_flag)
  73{
  74        int i = 0, cur_depth = 0;
  75        struct commit_list *result = NULL;
  76        struct object_array stack = OBJECT_ARRAY_INIT;
  77        struct commit *commit = NULL;
  78
  79        while (commit || i < heads->nr || stack.nr) {
  80                struct commit_list *p;
  81                if (!commit) {
  82                        if (i < heads->nr) {
  83                                commit = (struct commit *)
  84                                        deref_tag(heads->objects[i++].item, NULL, 0);
  85                                if (!commit || commit->object.type != OBJ_COMMIT) {
  86                                        commit = NULL;
  87                                        continue;
  88                                }
  89                                if (!commit->util)
  90                                        commit->util = xmalloc(sizeof(int));
  91                                *(int *)commit->util = 0;
  92                                cur_depth = 0;
  93                        } else {
  94                                commit = (struct commit *)
  95                                        stack.objects[--stack.nr].item;
  96                                cur_depth = *(int *)commit->util;
  97                        }
  98                }
  99                if (parse_commit(commit))
 100                        die("invalid commit");
 101                cur_depth++;
 102                if (cur_depth >= depth) {
 103                        commit_list_insert(commit, &result);
 104                        commit->object.flags |= shallow_flag;
 105                        commit = NULL;
 106                        continue;
 107                }
 108                commit->object.flags |= not_shallow_flag;
 109                for (p = commit->parents, commit = NULL; p; p = p->next) {
 110                        if (!p->item->util) {
 111                                int *pointer = xmalloc(sizeof(int));
 112                                p->item->util = pointer;
 113                                *pointer =  cur_depth;
 114                        } else {
 115                                int *pointer = p->item->util;
 116                                if (cur_depth >= *pointer)
 117                                        continue;
 118                                *pointer = cur_depth;
 119                        }
 120                        if (p->next)
 121                                add_object_array(&p->item->object,
 122                                                NULL, &stack);
 123                        else {
 124                                commit = p->item;
 125                                cur_depth = *(int *)commit->util;
 126                        }
 127                }
 128        }
 129
 130        return result;
 131}
 132
 133void check_shallow_file_for_update(void)
 134{
 135        struct stat st;
 136
 137        if (!is_shallow)
 138                return;
 139        else if (is_shallow == -1)
 140                die("BUG: shallow must be initialized by now");
 141
 142        if (stat(git_path("shallow"), &st))
 143                die("shallow file was removed during fetch");
 144        else if (st.st_mtime != shallow_stat.st_mtime
 145#ifdef USE_NSEC
 146                 || ST_MTIME_NSEC(st) != ST_MTIME_NSEC(shallow_stat)
 147#endif
 148                   )
 149                die("shallow file was changed during fetch");
 150}
 151
 152struct write_shallow_data {
 153        struct strbuf *out;
 154        int use_pack_protocol;
 155        int count;
 156};
 157
 158static int write_one_shallow(const struct commit_graft *graft, void *cb_data)
 159{
 160        struct write_shallow_data *data = cb_data;
 161        const char *hex = sha1_to_hex(graft->sha1);
 162        if (graft->nr_parent != -1)
 163                return 0;
 164        data->count++;
 165        if (data->use_pack_protocol)
 166                packet_buf_write(data->out, "shallow %s", hex);
 167        else {
 168                strbuf_addstr(data->out, hex);
 169                strbuf_addch(data->out, '\n');
 170        }
 171        return 0;
 172}
 173
 174int write_shallow_commits(struct strbuf *out, int use_pack_protocol,
 175                          const struct sha1_array *extra)
 176{
 177        struct write_shallow_data data;
 178        int i;
 179        data.out = out;
 180        data.use_pack_protocol = use_pack_protocol;
 181        data.count = 0;
 182        for_each_commit_graft(write_one_shallow, &data);
 183        if (!extra)
 184                return data.count;
 185        for (i = 0; i < extra->nr; i++) {
 186                strbuf_addstr(out, sha1_to_hex(extra->sha1[i]));
 187                strbuf_addch(out, '\n');
 188                data.count++;
 189        }
 190        return data.count;
 191}
 192
 193char *setup_temporary_shallow(const struct sha1_array *extra)
 194{
 195        struct strbuf sb = STRBUF_INIT;
 196        int fd;
 197
 198        if (write_shallow_commits(&sb, 0, extra)) {
 199                struct strbuf path = STRBUF_INIT;
 200                strbuf_addstr(&path, git_path("shallow_XXXXXX"));
 201                fd = xmkstemp(path.buf);
 202                if (write_in_full(fd, sb.buf, sb.len) != sb.len)
 203                        die_errno("failed to write to %s",
 204                                  path.buf);
 205                close(fd);
 206                strbuf_release(&sb);
 207                return strbuf_detach(&path, NULL);
 208        }
 209        /*
 210         * is_repository_shallow() sees empty string as "no shallow
 211         * file".
 212         */
 213        return xstrdup("");
 214}
 215
 216void setup_alternate_shallow(struct lock_file *shallow_lock,
 217                             const char **alternate_shallow_file,
 218                             const struct sha1_array *extra)
 219{
 220        struct strbuf sb = STRBUF_INIT;
 221        int fd;
 222
 223        check_shallow_file_for_update();
 224        fd = hold_lock_file_for_update(shallow_lock, git_path("shallow"),
 225                                       LOCK_DIE_ON_ERROR);
 226        if (write_shallow_commits(&sb, 0, extra)) {
 227                if (write_in_full(fd, sb.buf, sb.len) != sb.len)
 228                        die_errno("failed to write to %s",
 229                                  shallow_lock->filename);
 230                *alternate_shallow_file = shallow_lock->filename;
 231        } else
 232                /*
 233                 * is_repository_shallow() sees empty string as "no
 234                 * shallow file".
 235                 */
 236                *alternate_shallow_file = "";
 237        strbuf_release(&sb);
 238}
 239
 240static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
 241{
 242        int fd = *(int *)cb;
 243        if (graft->nr_parent == -1)
 244                packet_write(fd, "shallow %s\n", sha1_to_hex(graft->sha1));
 245        return 0;
 246}
 247
 248void advertise_shallow_grafts(int fd)
 249{
 250        if (!is_repository_shallow())
 251                return;
 252        for_each_commit_graft(advertise_shallow_grafts_cb, &fd);
 253}
 254
 255#define TRACE_KEY "GIT_TRACE_SHALLOW"
 256
 257/*
 258 * Step 1, split sender shallow commits into "ours" and "theirs"
 259 * Step 2, clean "ours" based on .git/shallow
 260 */
 261void prepare_shallow_info(struct shallow_info *info, struct sha1_array *sa)
 262{
 263        int i;
 264        trace_printf_key(TRACE_KEY, "shallow: prepare_shallow_info\n");
 265        memset(info, 0, sizeof(*info));
 266        info->shallow = sa;
 267        if (!sa)
 268                return;
 269        info->ours = xmalloc(sizeof(*info->ours) * sa->nr);
 270        info->theirs = xmalloc(sizeof(*info->theirs) * sa->nr);
 271        for (i = 0; i < sa->nr; i++) {
 272                if (has_sha1_file(sa->sha1[i])) {
 273                        struct commit_graft *graft;
 274                        graft = lookup_commit_graft(sa->sha1[i]);
 275                        if (graft && graft->nr_parent < 0)
 276                                continue;
 277                        info->ours[info->nr_ours++] = i;
 278                } else
 279                        info->theirs[info->nr_theirs++] = i;
 280        }
 281}
 282
 283void clear_shallow_info(struct shallow_info *info)
 284{
 285        free(info->ours);
 286        free(info->theirs);
 287}
 288
 289/* Step 4, remove non-existent ones in "theirs" after getting the pack */
 290
 291void remove_nonexistent_theirs_shallow(struct shallow_info *info)
 292{
 293        unsigned char (*sha1)[20] = info->shallow->sha1;
 294        int i, dst;
 295        trace_printf_key(TRACE_KEY, "shallow: remove_nonexistent_theirs_shallow\n");
 296        for (i = dst = 0; i < info->nr_theirs; i++) {
 297                if (i != dst)
 298                        info->theirs[dst] = info->theirs[i];
 299                if (has_sha1_file(sha1[info->theirs[i]]))
 300                        dst++;
 301        }
 302        info->nr_theirs = dst;
 303}
 304
 305/* Step 5, remove non-existent ones in "ours" in the pack */
 306void remove_nonexistent_ours_in_pack(struct shallow_info *info,
 307                                     struct packed_git *p)
 308{
 309        unsigned char (*sha1)[20] = info->shallow->sha1;
 310        int i, dst;
 311        trace_printf_key(TRACE_KEY, "shallow: remove_nonexistent_ours_in_pack\n");
 312        for (i = dst = 0; i < info->nr_ours; i++) {
 313                if (i != dst)
 314                        info->ours[dst] = info->ours[i];
 315                if (find_pack_entry_one(sha1[info->ours[i]], p))
 316                        dst++;
 317        }
 318        info->nr_ours = dst;
 319}