Documentation: describe --thin more accurately
[gitweb.git] / fast-import.c
index 25c3588385af63fdb9782ece39a1a4533b805260..b477dc6a8f8104cecf21b68375b7c5cf7ab8842c 100644 (file)
@@ -245,6 +245,7 @@ struct branch
        const char *name;
        struct tree_entry branch_tree;
        uintmax_t last_commit;
+       uintmax_t num_notes;
        unsigned active : 1;
        unsigned pack_id : PACK_ID_BITS;
        unsigned char sha1[20];
@@ -280,6 +281,7 @@ struct recent_command
 /* Configured limits on output */
 static unsigned long max_depth = 10;
 static off_t max_packsize = (1LL << 32) - 1;
+static uintmax_t big_file_threshold = 512 * 1024 * 1024;
 static int force_update;
 static int pack_compression_level = Z_DEFAULT_COMPRESSION;
 static int pack_compression_seen;
@@ -702,6 +704,7 @@ static struct branch *new_branch(const char *name)
        b->table_next_branch = branch_table[hc];
        b->branch_tree.versions[0].mode = S_IFDIR;
        b->branch_tree.versions[1].mode = S_IFDIR;
+       b->num_notes = 0;
        b->active = 0;
        b->pack_id = MAX_PACK_ID;
        branch_table[hc] = b;
@@ -1012,7 +1015,7 @@ static void cycle_packfile(void)
 
 static size_t encode_header(
        enum object_type type,
-       size_t size,
+       uintmax_t size,
        unsigned char *hdr)
 {
        int n = 1;
@@ -1168,6 +1171,118 @@ static int store_object(
        return 0;
 }
 
+static void truncate_pack(off_t to)
+{
+       if (ftruncate(pack_data->pack_fd, to)
+        || lseek(pack_data->pack_fd, to, SEEK_SET) != to)
+               die_errno("cannot truncate pack to skip duplicate");
+       pack_size = to;
+}
+
+static void stream_blob(uintmax_t len, unsigned char *sha1out, uintmax_t mark)
+{
+       size_t in_sz = 64 * 1024, out_sz = 64 * 1024;
+       unsigned char *in_buf = xmalloc(in_sz);
+       unsigned char *out_buf = xmalloc(out_sz);
+       struct object_entry *e;
+       unsigned char sha1[20];
+       unsigned long hdrlen;
+       off_t offset;
+       git_SHA_CTX c;
+       z_stream s;
+       int status = Z_OK;
+
+       /* Determine if we should auto-checkpoint. */
+       if ((pack_size + 60 + len) > max_packsize
+               || (pack_size + 60 + len) < pack_size)
+               cycle_packfile();
+
+       offset = pack_size;
+
+       hdrlen = snprintf((char *)out_buf, out_sz, "blob %" PRIuMAX, len) + 1;
+       if (out_sz <= hdrlen)
+               die("impossibly large object header");
+
+       git_SHA1_Init(&c);
+       git_SHA1_Update(&c, out_buf, hdrlen);
+
+       memset(&s, 0, sizeof(s));
+       deflateInit(&s, pack_compression_level);
+
+       hdrlen = encode_header(OBJ_BLOB, len, out_buf);
+       if (out_sz <= hdrlen)
+               die("impossibly large object header");
+
+       s.next_out = out_buf + hdrlen;
+       s.avail_out = out_sz - hdrlen;
+
+       while (status != Z_STREAM_END) {
+               if (0 < len && !s.avail_in) {
+                       size_t cnt = in_sz < len ? in_sz : (size_t)len;
+                       size_t n = fread(in_buf, 1, cnt, stdin);
+                       if (!n && feof(stdin))
+                               die("EOF in data (%" PRIuMAX " bytes remaining)", len);
+
+                       git_SHA1_Update(&c, in_buf, n);
+                       s.next_in = in_buf;
+                       s.avail_in = n;
+                       len -= n;
+               }
+
+               status = deflate(&s, len ? 0 : Z_FINISH);
+
+               if (!s.avail_out || status == Z_STREAM_END) {
+                       size_t n = s.next_out - out_buf;
+                       write_or_die(pack_data->pack_fd, out_buf, n);
+                       pack_size += n;
+                       s.next_out = out_buf;
+                       s.avail_out = out_sz;
+               }
+
+               switch (status) {
+               case Z_OK:
+               case Z_BUF_ERROR:
+               case Z_STREAM_END:
+                       continue;
+               default:
+                       die("unexpected deflate failure: %d", status);
+               }
+       }
+       deflateEnd(&s);
+       git_SHA1_Final(sha1, &c);
+
+       if (sha1out)
+               hashcpy(sha1out, sha1);
+
+       e = insert_object(sha1);
+
+       if (mark)
+               insert_mark(mark, e);
+
+       if (e->offset) {
+               duplicate_count_by_type[OBJ_BLOB]++;
+               truncate_pack(offset);
+
+       } else if (find_sha1_pack(sha1, packed_git)) {
+               e->type = OBJ_BLOB;
+               e->pack_id = MAX_PACK_ID;
+               e->offset = 1; /* just not zero! */
+               duplicate_count_by_type[OBJ_BLOB]++;
+               truncate_pack(offset);
+
+       } else {
+               e->depth = 0;
+               e->type = OBJ_BLOB;
+               e->pack_id = pack_id;
+               e->offset = offset;
+               object_count++;
+               object_count_by_type[OBJ_BLOB]++;
+       }
+
+       free(in_buf);
+       free(out_buf);
+}
+
 /* All calls must be guarded by find_object() or find_mark() to
  * ensure the 'struct object_entry' passed was written by this
  * process instance.  We unpack the entry by the offset, avoiding
@@ -1755,7 +1870,7 @@ static void parse_mark(void)
                next_mark = 0;
 }
 
-static void parse_data(struct strbuf *sb)
+static int parse_data(struct strbuf *sb, uintmax_t limit, uintmax_t *len_res)
 {
        strbuf_reset(sb);
 
@@ -1779,9 +1894,15 @@ static void parse_data(struct strbuf *sb)
                free(term);
        }
        else {
-               size_t n = 0, length;
+               uintmax_t len = strtoumax(command_buf.buf + 5, NULL, 10);
+               size_t n = 0, length = (size_t)len;
 
-               length = strtoul(command_buf.buf + 5, NULL, 10);
+               if (limit && limit < len) {
+                       *len_res = len;
+                       return 0;
+               }
+               if (length < len)
+                       die("data is too large to use in this context");
 
                while (n < length) {
                        size_t s = strbuf_fread(sb, length - n, stdin);
@@ -1793,6 +1914,7 @@ static void parse_data(struct strbuf *sb)
        }
 
        skip_optional_lf();
+       return 1;
 }
 
 static int validate_raw_date(const char *src, char *result, int maxlen)
@@ -1857,14 +1979,32 @@ static char *parse_ident(const char *buf)
        return ident;
 }
 
-static void parse_new_blob(void)
+static void parse_and_store_blob(
+       struct last_object *last,
+       unsigned char *sha1out,
+       uintmax_t mark)
 {
        static struct strbuf buf = STRBUF_INIT;
+       uintmax_t len;
+
+       if (parse_data(&buf, big_file_threshold, &len))
+               store_object(OBJ_BLOB, &buf, last, sha1out, mark);
+       else {
+               if (last) {
+                       strbuf_release(&last->data);
+                       last->offset = 0;
+                       last->depth = 0;
+               }
+               stream_blob(len, sha1out, mark);
+               skip_optional_lf();
+       }
+}
 
+static void parse_new_blob(void)
+{
        read_next_command();
        parse_mark();
-       parse_data(&buf);
-       store_object(OBJ_BLOB, &buf, &last_blob, NULL, next_mark);
+       parse_and_store_blob(&last_blob, NULL, next_mark);
 }
 
 static void unload_one_branch(void)
@@ -1911,6 +2051,109 @@ static void load_branch(struct branch *b)
        }
 }
 
+static unsigned char convert_num_notes_to_fanout(uintmax_t num_notes)
+{
+       unsigned char fanout = 0;
+       while ((num_notes >>= 8))
+               fanout++;
+       return fanout;
+}
+
+static void construct_path_with_fanout(const char *hex_sha1,
+               unsigned char fanout, char *path)
+{
+       unsigned int i = 0, j = 0;
+       if (fanout >= 20)
+               die("Too large fanout (%u)", fanout);
+       while (fanout) {
+               path[i++] = hex_sha1[j++];
+               path[i++] = hex_sha1[j++];
+               path[i++] = '/';
+               fanout--;
+       }
+       memcpy(path + i, hex_sha1 + j, 40 - j);
+       path[i + 40 - j] = '\0';
+}
+
+static uintmax_t do_change_note_fanout(
+               struct tree_entry *orig_root, struct tree_entry *root,
+               char *hex_sha1, unsigned int hex_sha1_len,
+               char *fullpath, unsigned int fullpath_len,
+               unsigned char fanout)
+{
+       struct tree_content *t = root->tree;
+       struct tree_entry *e, leaf;
+       unsigned int i, tmp_hex_sha1_len, tmp_fullpath_len;
+       uintmax_t num_notes = 0;
+       unsigned char sha1[20];
+       char realpath[60];
+
+       for (i = 0; t && i < t->entry_count; i++) {
+               e = t->entries[i];
+               tmp_hex_sha1_len = hex_sha1_len + e->name->str_len;
+               tmp_fullpath_len = fullpath_len;
+
+               /*
+                * We're interested in EITHER existing note entries (entries
+                * with exactly 40 hex chars in path, not including directory
+                * separators), OR directory entries that may contain note
+                * entries (with < 40 hex chars in path).
+                * Also, each path component in a note entry must be a multiple
+                * of 2 chars.
+                */
+               if (!e->versions[1].mode ||
+                   tmp_hex_sha1_len > 40 ||
+                   e->name->str_len % 2)
+                       continue;
+
+               /* This _may_ be a note entry, or a subdir containing notes */
+               memcpy(hex_sha1 + hex_sha1_len, e->name->str_dat,
+                      e->name->str_len);
+               if (tmp_fullpath_len)
+                       fullpath[tmp_fullpath_len++] = '/';
+               memcpy(fullpath + tmp_fullpath_len, e->name->str_dat,
+                      e->name->str_len);
+               tmp_fullpath_len += e->name->str_len;
+               fullpath[tmp_fullpath_len] = '\0';
+
+               if (tmp_hex_sha1_len == 40 && !get_sha1_hex(hex_sha1, sha1)) {
+                       /* This is a note entry */
+                       construct_path_with_fanout(hex_sha1, fanout, realpath);
+                       if (!strcmp(fullpath, realpath)) {
+                               /* Note entry is in correct location */
+                               num_notes++;
+                               continue;
+                       }
+
+                       /* Rename fullpath to realpath */
+                       if (!tree_content_remove(orig_root, fullpath, &leaf))
+                               die("Failed to remove path %s", fullpath);
+                       tree_content_set(orig_root, realpath,
+                               leaf.versions[1].sha1,
+                               leaf.versions[1].mode,
+                               leaf.tree);
+               } else if (S_ISDIR(e->versions[1].mode)) {
+                       /* This is a subdir that may contain note entries */
+                       if (!e->tree)
+                               load_tree(e);
+                       num_notes += do_change_note_fanout(orig_root, e,
+                               hex_sha1, tmp_hex_sha1_len,
+                               fullpath, tmp_fullpath_len, fanout);
+               }
+
+               /* The above may have reallocated the current tree_content */
+               t = root->tree;
+       }
+       return num_notes;
+}
+
+static uintmax_t change_note_fanout(struct tree_entry *root,
+               unsigned char fanout)
+{
+       char hex_sha1[40], path[60];
+       return do_change_note_fanout(root, root, hex_sha1, 0, path, 0, fanout);
+}
+
 static void file_change_m(struct branch *b)
 {
        const char *p = command_buf.buf + 2;
@@ -1975,15 +2218,12 @@ static void file_change_m(struct branch *b)
                 * another repository.
                 */
        } else if (inline_data) {
-               static struct strbuf buf = STRBUF_INIT;
-
                if (p != uq.buf) {
                        strbuf_addstr(&uq, p);
                        p = uq.buf;
                }
                read_next_command();
-               parse_data(&buf);
-               store_object(OBJ_BLOB, &buf, &last_blob, sha1, 0);
+               parse_and_store_blob(&last_blob, sha1, 0);
        } else if (oe) {
                if (oe->type != OBJ_BLOB)
                        die("Not a blob (actually a %s): %s",
@@ -2061,14 +2301,16 @@ static void file_change_cr(struct branch *b, int rename)
                leaf.tree);
 }
 
-static void note_change_n(struct branch *b)
+static void note_change_n(struct branch *b, unsigned char old_fanout)
 {
        const char *p = command_buf.buf + 2;
        static struct strbuf uq = STRBUF_INIT;
        struct object_entry *oe = oe;
        struct branch *s;
        unsigned char sha1[20], commit_sha1[20];
+       char path[60];
        uint16_t inline_data = 0;
+       unsigned char new_fanout;
 
        /* <dataref> or 'inline' */
        if (*p == ':') {
@@ -2109,20 +2351,17 @@ static void note_change_n(struct branch *b)
                die("Invalid ref name or SHA1 expression: %s", p);
 
        if (inline_data) {
-               static struct strbuf buf = STRBUF_INIT;
-
                if (p != uq.buf) {
                        strbuf_addstr(&uq, p);
                        p = uq.buf;
                }
                read_next_command();
-               parse_data(&buf);
-               store_object(OBJ_BLOB, &buf, &last_blob, sha1, 0);
+               parse_and_store_blob(&last_blob, sha1, 0);
        } else if (oe) {
                if (oe->type != OBJ_BLOB)
                        die("Not a blob (actually a %s): %s",
                                typename(oe->type), command_buf.buf);
-       } else {
+       } else if (!is_null_sha1(sha1)) {
                enum object_type type = sha1_object_info(sha1, NULL);
                if (type < 0)
                        die("Blob not found: %s", command_buf.buf);
@@ -2131,8 +2370,17 @@ static void note_change_n(struct branch *b)
                            typename(type), command_buf.buf);
        }
 
-       tree_content_set(&b->branch_tree, sha1_to_hex(commit_sha1), sha1,
-               S_IFREG | 0644, NULL);
+       construct_path_with_fanout(sha1_to_hex(commit_sha1), old_fanout, path);
+       if (tree_content_remove(&b->branch_tree, path, NULL))
+               b->num_notes--;
+
+       if (is_null_sha1(sha1))
+               return; /* nothing to insert */
+
+       b->num_notes++;
+       new_fanout = convert_num_notes_to_fanout(b->num_notes);
+       construct_path_with_fanout(sha1_to_hex(commit_sha1), new_fanout, path);
+       tree_content_set(&b->branch_tree, path, sha1, S_IFREG | 0644, NULL);
 }
 
 static void file_change_deleteall(struct branch *b)
@@ -2141,6 +2389,7 @@ static void file_change_deleteall(struct branch *b)
        hashclr(b->branch_tree.versions[0].sha1);
        hashclr(b->branch_tree.versions[1].sha1);
        load_tree(&b->branch_tree);
+       b->num_notes = 0;
 }
 
 static void parse_from_commit(struct branch *b, char *buf, unsigned long size)
@@ -2264,6 +2513,7 @@ static void parse_new_commit(void)
        char *committer = NULL;
        struct hash_list *merge_list = NULL;
        unsigned int merge_count;
+       unsigned char prev_fanout, new_fanout;
 
        /* Obtain the branch name from the rest of our command */
        sp = strchr(command_buf.buf, ' ') + 1;
@@ -2283,7 +2533,7 @@ static void parse_new_commit(void)
        }
        if (!committer)
                die("Expected committer but didn't get one");
-       parse_data(&msg);
+       parse_data(&msg, 0, NULL);
        read_next_command();
        parse_from(b);
        merge_list = parse_merge(&merge_count);
@@ -2294,6 +2544,8 @@ static void parse_new_commit(void)
                load_branch(b);
        }
 
+       prev_fanout = convert_num_notes_to_fanout(b->num_notes);
+
        /* file_change* */
        while (command_buf.len > 0) {
                if (!prefixcmp(command_buf.buf, "M "))
@@ -2305,7 +2557,7 @@ static void parse_new_commit(void)
                else if (!prefixcmp(command_buf.buf, "C "))
                        file_change_cr(b, 0);
                else if (!prefixcmp(command_buf.buf, "N "))
-                       note_change_n(b);
+                       note_change_n(b, prev_fanout);
                else if (!strcmp("deleteall", command_buf.buf))
                        file_change_deleteall(b);
                else {
@@ -2316,6 +2568,10 @@ static void parse_new_commit(void)
                        break;
        }
 
+       new_fanout = convert_num_notes_to_fanout(b->num_notes);
+       if (new_fanout != prev_fanout)
+               b->num_notes = change_note_fanout(&b->branch_tree, new_fanout);
+
        /* build the tree and the commit */
        store_tree(&b->branch_tree);
        hashcpy(b->branch_tree.versions[0].sha1,
@@ -2404,7 +2660,7 @@ static void parse_new_tag(void)
                tagger = NULL;
 
        /* tag payload/message */
-       parse_data(&msg);
+       parse_data(&msg, 0, NULL);
 
        /* build the tag object */
        strbuf_reset(&new_data);
@@ -2508,11 +2764,6 @@ static void option_date_format(const char *fmt)
                die("unknown --date-format argument %s", fmt);
 }
 
-static void option_max_pack_size(const char *packsize)
-{
-       max_packsize = strtoumax(packsize, NULL, 0) * 1024 * 1024;
-}
-
 static void option_depth(const char *depth)
 {
        max_depth = strtoul(depth, NULL, 0);
@@ -2542,7 +2793,22 @@ static void option_export_pack_edges(const char *edges)
 static int parse_one_option(const char *option)
 {
        if (!prefixcmp(option, "max-pack-size=")) {
-               option_max_pack_size(option + 14);
+               unsigned long v;
+               if (!git_parse_ulong(option + 14, &v))
+                       return 0;
+               if (v < 8192) {
+                       warning("max-pack-size is now in bytes, assuming --max-pack-size=%lum", v);
+                       v *= 1024 * 1024;
+               } else if (v < 1024 * 1024) {
+                       warning("minimum max-pack-size is 1 MiB");
+                       v = 1024 * 1024;
+               }
+               max_packsize = v;
+       } else if (!prefixcmp(option, "big-file-threshold=")) {
+               unsigned long v;
+               if (!git_parse_ulong(option + 19, &v))
+                       return 0;
+               big_file_threshold = v;
        } else if (!prefixcmp(option, "depth=")) {
                option_depth(option + 6);
        } else if (!prefixcmp(option, "active-branches=")) {
@@ -2625,11 +2891,15 @@ static int git_pack_config(const char *k, const char *v, void *cb)
                pack_compression_seen = 1;
                return 0;
        }
+       if (!strcmp(k, "core.bigfilethreshold")) {
+               long n = git_config_int(k, v);
+               big_file_threshold = 0 < n ? n : 0;
+       }
        return git_default_config(k, v, cb);
 }
 
 static const char fast_import_usage[] =
-"git fast-import [--date-format=f] [--max-pack-size=n] [--depth=n] [--active-branches=n] [--export-marks=marks.file]";
+"git fast-import [--date-format=f] [--max-pack-size=n] [--big-file-threshold=n] [--depth=n] [--active-branches=n] [--export-marks=marks.file]";
 
 static void parse_argv(void)
 {