show-branch -g: default to the current branch.
[gitweb.git] / builtin-pack-objects.c
index 96c069a81da643b7ee3515ca8c89734881fa3b77..3824ee33acb2f984419ab79c2f3ecc306d3e5ea5 100644 (file)
 #include "diff.h"
 #include "revision.h"
 #include "list-objects.h"
-#include <sys/time.h>
-#include <signal.h>
 
-static const char pack_usage[] = "git-pack-objects [-q] [--no-reuse-delta] [--non-empty] [--local] [--incremental] [--window=N] [--depth=N] [--revs [--unpacked | --all]*] [--stdout | base-name] <ref-list | <object-list]";
+static const char pack_usage[] = "\
+git-pack-objects [{ -q | --progress | --all-progress }] \n\
+       [--local] [--incremental] [--window=N] [--depth=N] \n\
+       [--no-reuse-delta] [--delta-base-offset] [--non-empty] \n\
+       [--revs [--unpacked | --all]*] [--reflog] [--stdout | base-name] \n\
+       [<ref-list | <object-list]";
 
 struct object_entry {
        unsigned char sha1[20];
@@ -29,6 +32,7 @@ struct object_entry {
        enum object_type type;
        enum object_type in_pack_type;  /* could be delta */
        unsigned long delta_size;       /* delta data size (uncompressed) */
+#define in_pack_header_size delta_size /* only when reusing pack data */
        struct object_entry *delta;     /* delta base object */
        struct packed_git *in_pack;     /* already in pack */
        unsigned int in_pack_offset;
@@ -60,6 +64,8 @@ static int non_empty;
 static int no_reuse_delta;
 static int local;
 static int incremental;
+static int allow_ofs_delta;
+
 static struct object_entry **sorted_by_sha, **sorted_by_type;
 static struct object_entry *objects;
 static int nr_objects, nr_alloc, nr_result;
@@ -84,17 +90,25 @@ static int object_ix_hashsz;
  * Pack index for existing packs give us easy access to the offsets into
  * corresponding pack file where each object's data starts, but the entries
  * do not store the size of the compressed representation (uncompressed
- * size is easily available by examining the pack entry header).  We build
- * a hashtable of existing packs (pack_revindex), and keep reverse index
- * here -- pack index file is sorted by object name mapping to offset; this
- * pack_revindex[].revindex array is an ordered list of offsets, so if you
- * know the offset of an object, next offset is where its packed
- * representation ends.
+ * size is easily available by examining the pack entry header).  It is
+ * also rather expensive to find the sha1 for an object given its offset.
+ *
+ * We build a hashtable of existing packs (pack_revindex), and keep reverse
+ * index here -- pack index file is sorted by object name mapping to offset;
+ * this pack_revindex[].revindex array is a list of offset/index_nr pairs
+ * ordered by offset, so if you know the offset of an object, next offset
+ * is where its packed representation ends and the index_nr can be used to
+ * get the object sha1 from the main index.
  */
+struct revindex_entry {
+       unsigned int offset;
+       unsigned int nr;
+};
 struct pack_revindex {
        struct packed_git *p;
-       unsigned long *revindex;
-} *pack_revindex = NULL;
+       struct revindex_entry *revindex;
+};
+static struct  pack_revindex *pack_revindex;
 static int pack_revindex_hashsz;
 
 /*
@@ -141,14 +155,9 @@ static void prepare_pack_ix(void)
 
 static int cmp_offset(const void *a_, const void *b_)
 {
-       unsigned long a = *(unsigned long *) a_;
-       unsigned long b = *(unsigned long *) b_;
-       if (a < b)
-               return -1;
-       else if (a == b)
-               return 0;
-       else
-               return 1;
+       const struct revindex_entry *a = a_;
+       const struct revindex_entry *b = b_;
+       return (a->offset < b->offset) ? -1 : (a->offset > b->offset) ? 1 : 0;
 }
 
 /*
@@ -161,25 +170,27 @@ static void prepare_pack_revindex(struct pack_revindex *rix)
        int i;
        void *index = p->index_base + 256;
 
-       rix->revindex = xmalloc(sizeof(unsigned long) * (num_ent + 1));
+       rix->revindex = xmalloc(sizeof(*rix->revindex) * (num_ent + 1));
        for (i = 0; i < num_ent; i++) {
                unsigned int hl = *((unsigned int *)((char *) index + 24*i));
-               rix->revindex[i] = ntohl(hl);
+               rix->revindex[i].offset = ntohl(hl);
+               rix->revindex[i].nr = i;
        }
        /* This knows the pack format -- the 20-byte trailer
         * follows immediately after the last object data.
         */
-       rix->revindex[num_ent] = p->pack_size - 20;
-       qsort(rix->revindex, num_ent, sizeof(unsigned long), cmp_offset);
+       rix->revindex[num_ent].offset = p->pack_size - 20;
+       rix->revindex[num_ent].nr = -1;
+       qsort(rix->revindex, num_ent, sizeof(*rix->revindex), cmp_offset);
 }
 
-static unsigned long find_packed_object_size(struct packed_git *p,
-                                            unsigned long ofs)
+static struct revindex_entry * find_packed_object(struct packed_git *p,
+                                                 unsigned int ofs)
 {
        int num;
        int lo, hi;
        struct pack_revindex *rix;
-       unsigned long *revindex;
+       struct revindex_entry *revindex;
        num = pack_revindex_ix(p);
        if (num < 0)
                die("internal error: pack revindex uninitialized");
@@ -191,10 +202,10 @@ static unsigned long find_packed_object_size(struct packed_git *p,
        hi = num_packed_objects(p) + 1;
        do {
                int mi = (lo + hi) / 2;
-               if (revindex[mi] == ofs) {
-                       return revindex[mi+1] - ofs;
+               if (revindex[mi].offset == ofs) {
+                       return revindex + mi;
                }
-               else if (ofs < revindex[mi])
+               else if (ofs < revindex[mi].offset)
                        hi = mi;
                else
                        lo = mi + 1;
@@ -202,6 +213,20 @@ static unsigned long find_packed_object_size(struct packed_git *p,
        die("internal error: pack revindex corrupt");
 }
 
+static unsigned long find_packed_object_size(struct packed_git *p,
+                                            unsigned long ofs)
+{
+       struct revindex_entry *entry = find_packed_object(p, ofs);
+       return entry[1].offset - ofs;
+}
+
+static unsigned char *find_packed_object_name(struct packed_git *p,
+                                             unsigned long ofs)
+{
+       struct revindex_entry *entry = find_packed_object(p, ofs);
+       return (unsigned char *)(p->index_base + 256) + 24 * entry->nr + 4;
+}
+
 static void *delta_against(void *buf, unsigned long size, struct object_entry *entry)
 {
        unsigned long othersize, delta_size;
@@ -232,7 +257,7 @@ static int encode_header(enum object_type type, unsigned long size, unsigned cha
        int n = 1;
        unsigned char c;
 
-       if (type < OBJ_COMMIT || type > OBJ_DELTA)
+       if (type < OBJ_COMMIT || type > OBJ_REF_DELTA)
                die("bad type %d", type);
 
        c = (type << 4) | (size & 15);
@@ -247,7 +272,56 @@ static int encode_header(enum object_type type, unsigned long size, unsigned cha
        return n;
 }
 
-static int check_inflate(unsigned char *data, unsigned long len, unsigned long expect)
+/*
+ * we are going to reuse the existing object data as is.  make
+ * sure it is not corrupt.
+ */
+static int check_pack_inflate(struct packed_git *p,
+               struct pack_window **w_curs,
+               unsigned long offset,
+               unsigned long len,
+               unsigned long expect)
+{
+       z_stream stream;
+       unsigned char fakebuf[4096], *in;
+       int st;
+
+       memset(&stream, 0, sizeof(stream));
+       inflateInit(&stream);
+       do {
+               in = use_pack(p, w_curs, offset, &stream.avail_in);
+               stream.next_in = in;
+               stream.next_out = fakebuf;
+               stream.avail_out = sizeof(fakebuf);
+               st = inflate(&stream, Z_FINISH);
+               offset += stream.next_in - in;
+       } while (st == Z_OK || st == Z_BUF_ERROR);
+       inflateEnd(&stream);
+       return (st == Z_STREAM_END &&
+               stream.total_out == expect &&
+               stream.total_in == len) ? 0 : -1;
+}
+
+static void copy_pack_data(struct sha1file *f,
+               struct packed_git *p,
+               struct pack_window **w_curs,
+               unsigned long offset,
+               unsigned long len)
+{
+       unsigned char *in;
+       unsigned int avail;
+
+       while (len) {
+               in = use_pack(p, w_curs, offset, &avail);
+               if (avail > len)
+                       avail = len;
+               sha1write(f, in, avail);
+               offset += avail;
+               len -= avail;
+       }
+}
+
+static int check_loose_inflate(unsigned char *data, unsigned long len, unsigned long expect)
 {
        z_stream stream;
        unsigned char fakebuf[4096];
@@ -278,32 +352,6 @@ static int check_inflate(unsigned char *data, unsigned long len, unsigned long e
        return st;
 }
 
-/*
- * we are going to reuse the existing pack entry data.  make
- * sure it is not corrupt.
- */
-static int revalidate_pack_entry(struct object_entry *entry, unsigned char *data, unsigned long len)
-{
-       enum object_type type;
-       unsigned long size, used;
-
-       if (pack_to_stdout)
-               return 0;
-
-       /* the caller has already called use_packed_git() for us,
-        * so it is safe to access the pack data from mmapped location.
-        * make sure the entry inflates correctly.
-        */
-       used = unpack_object_header_gently(data, len, &type, &size);
-       if (!used)
-               return -1;
-       if (type == OBJ_DELTA)
-               used += 20; /* skip base object name */
-       data += used;
-       len -= used;
-       return check_inflate(data, len, entry->size);
-}
-
 static int revalidate_loose_object(struct object_entry *entry,
                                   unsigned char *map,
                                   unsigned long mapsize)
@@ -320,7 +368,7 @@ static int revalidate_loose_object(struct object_entry *entry,
                return -1;
        map += used;
        mapsize -= used;
-       return check_inflate(map, mapsize, size);
+       return check_loose_inflate(map, mapsize, size);
 }
 
 static unsigned long write_object(struct sha1file *f,
@@ -334,13 +382,10 @@ static unsigned long write_object(struct sha1file *f,
        enum object_type obj_type;
        int to_reuse = 0;
 
-       if (entry->preferred_base)
-               return 0;
-
        obj_type = entry->type;
        if (! entry->in_pack)
                to_reuse = 0;   /* can't reuse what we don't have */
-       else if (obj_type == OBJ_DELTA)
+       else if (obj_type == OBJ_REF_DELTA || obj_type == OBJ_OFS_DELTA)
                to_reuse = 1;   /* check_object() decided it for us */
        else if (obj_type != entry->in_pack_type)
                to_reuse = 0;   /* pack has delta which is unusable */
@@ -380,18 +425,35 @@ static unsigned long write_object(struct sha1file *f,
                if (entry->delta) {
                        buf = delta_against(buf, size, entry);
                        size = entry->delta_size;
-                       obj_type = OBJ_DELTA;
+                       obj_type = (allow_ofs_delta && entry->delta->offset) ?
+                               OBJ_OFS_DELTA : OBJ_REF_DELTA;
                }
                /*
                 * The object header is a byte of 'type' followed by zero or
-                * more bytes of length.  For deltas, the 20 bytes of delta
-                * sha1 follows that.
+                * more bytes of length.
                 */
                hdrlen = encode_header(obj_type, size, header);
                sha1write(f, header, hdrlen);
 
-               if (entry->delta) {
-                       sha1write(f, entry->delta, 20);
+               if (obj_type == OBJ_OFS_DELTA) {
+                       /*
+                        * Deltas with relative base contain an additional
+                        * encoding of the relative offset for the delta
+                        * base from this object's position in the pack.
+                        */
+                       unsigned long ofs = entry->offset - entry->delta->offset;
+                       unsigned pos = sizeof(header) - 1;
+                       header[pos] = ofs & 127;
+                       while (ofs >>= 7)
+                               header[--pos] = 128 | (--ofs & 127);
+                       sha1write(f, header + pos, sizeof(header) - pos);
+                       hdrlen += sizeof(header) - pos;
+               } else if (obj_type == OBJ_REF_DELTA) {
+                       /*
+                        * Deltas with a base reference contain
+                        * an additional 20 bytes for the base sha1.
+                        */
+                       sha1write(f, entry->delta->sha1, 20);
                        hdrlen += 20;
                }
                datalen = sha1write_compressed(f, buf, size);
@@ -399,21 +461,40 @@ static unsigned long write_object(struct sha1file *f,
        }
        else {
                struct packed_git *p = entry->in_pack;
-               use_packed_git(p);
+               struct pack_window *w_curs = NULL;
+               unsigned long offset;
 
-               datalen = find_packed_object_size(p, entry->in_pack_offset);
-               buf = (char *) p->pack_base + entry->in_pack_offset;
+               if (entry->delta) {
+                       obj_type = (allow_ofs_delta && entry->delta->offset) ?
+                               OBJ_OFS_DELTA : OBJ_REF_DELTA;
+                       reused_delta++;
+               }
+               hdrlen = encode_header(obj_type, entry->size, header);
+               sha1write(f, header, hdrlen);
+               if (obj_type == OBJ_OFS_DELTA) {
+                       unsigned long ofs = entry->offset - entry->delta->offset;
+                       unsigned pos = sizeof(header) - 1;
+                       header[pos] = ofs & 127;
+                       while (ofs >>= 7)
+                               header[--pos] = 128 | (--ofs & 127);
+                       sha1write(f, header + pos, sizeof(header) - pos);
+                       hdrlen += sizeof(header) - pos;
+               } else if (obj_type == OBJ_REF_DELTA) {
+                       sha1write(f, entry->delta->sha1, 20);
+                       hdrlen += 20;
+               }
 
-               if (revalidate_pack_entry(entry, buf, datalen))
+               offset = entry->in_pack_offset + entry->in_pack_header_size;
+               datalen = find_packed_object_size(p, entry->in_pack_offset)
+                               - entry->in_pack_header_size;
+               if (!pack_to_stdout && check_pack_inflate(p, &w_curs,
+                               offset, datalen, entry->size))
                        die("corrupt delta in pack %s", sha1_to_hex(entry->sha1));
-               sha1write(f, buf, datalen);
-               unuse_packed_git(p);
-               hdrlen = 0; /* not really */
-               if (obj_type == OBJ_DELTA)
-                       reused_delta++;
+               copy_pack_data(f, p, &w_curs, offset, datalen);
+               unuse_pack(&w_curs);
                reused++;
        }
-       if (obj_type == OBJ_DELTA)
+       if (entry->delta)
                written_delta++;
        written++;
        return hdrlen + datalen;
@@ -423,17 +504,16 @@ static unsigned long write_one(struct sha1file *f,
                               struct object_entry *e,
                               unsigned long offset)
 {
-       if (e->offset)
+       if (e->offset || e->preferred_base)
                /* offset starts from header size and cannot be zero
                 * if it is written already.
                 */
                return offset;
-       e->offset = offset;
-       offset += write_object(f, e);
-       /* if we are deltified, write out its base object. */
+       /* if we are deltified, write out its base object first. */
        if (e->delta)
                offset = write_one(f, e->delta, offset);
-       return offset;
+       e->offset = offset;
+       return offset + write_object(f, e);
 }
 
 static void write_pack_file(void)
@@ -443,15 +523,15 @@ static void write_pack_file(void)
        unsigned long offset;
        struct pack_header hdr;
        unsigned last_percent = 999;
-       int do_progress = 0;
+       int do_progress = progress;
 
-       if (!base_name)
+       if (!base_name) {
                f = sha1fd(1, "<stdout>");
-       else {
+               do_progress >>= 1;
+       }
+       else
                f = sha1create("%s-%s.%s", base_name,
                               sha1_to_hex(object_list_sha1), "pack");
-               do_progress = progress;
-       }
        if (do_progress)
                fprintf(stderr, "Writing %d objects.\n", nr_result);
 
@@ -477,6 +557,8 @@ static void write_pack_file(void)
        if (do_progress)
                fputc('\n', stderr);
  done:
+       if (written != nr_result)
+               die("wrote %d objects while expecting %d", written, nr_result);
        sha1close(f, pack_file_sha1, 1);
 }
 
@@ -487,7 +569,7 @@ static void write_index_file(void)
                                        sha1_to_hex(object_list_sha1), "idx");
        struct object_entry **list = sorted_by_sha;
        struct object_entry **last = list + nr_result;
-       unsigned int array[256];
+       uint32_t array[256];
 
        /*
         * Write the first-level table (the list is sorted,
@@ -505,7 +587,7 @@ static void write_index_file(void)
                array[i] = htonl(next - sorted_by_sha);
                list = next;
        }
-       sha1write(f, array, 256 * sizeof(int));
+       sha1write(f, array, 256 * 4);
 
        /*
         * Write the actual SHA1 entries..
@@ -513,7 +595,7 @@ static void write_index_file(void)
        list = sorted_by_sha;
        for (i = 0; i < nr_result; i++) {
                struct object_entry *entry = *list++;
-               unsigned int offset = htonl(entry->offset);
+               uint32_t offset = htonl(entry->offset);
                sha1write(f, &offset, 4);
                sha1write(f, entry->sha1, 20);
        }
@@ -899,26 +981,67 @@ static void check_object(struct object_entry *entry)
        char type[20];
 
        if (entry->in_pack && !entry->preferred_base) {
-               unsigned char base[20];
-               unsigned long size;
-               struct object_entry *base_entry;
+               struct packed_git *p = entry->in_pack;
+               struct pack_window *w_curs = NULL;
+               unsigned long left = p->pack_size - entry->in_pack_offset;
+               unsigned long size, used;
+               unsigned char *buf;
+               struct object_entry *base_entry = NULL;
+
+               buf = use_pack(p, &w_curs, entry->in_pack_offset, NULL);
 
                /* We want in_pack_type even if we do not reuse delta.
                 * There is no point not reusing non-delta representations.
                 */
-               check_reuse_pack_delta(entry->in_pack,
-                                      entry->in_pack_offset,
-                                      base, &size,
-                                      &entry->in_pack_type);
+               used = unpack_object_header_gently(buf, left,
+                                                  &entry->in_pack_type, &size);
 
                /* Check if it is delta, and the base is also an object
                 * we are going to pack.  If so we will reuse the existing
                 * delta.
                 */
-               if (!no_reuse_delta &&
-                   entry->in_pack_type == OBJ_DELTA &&
-                   (base_entry = locate_object_entry(base)) &&
-                   (!base_entry->preferred_base)) {
+               if (!no_reuse_delta) {
+                       unsigned char c, *base_name;
+                       unsigned long ofs;
+                       unsigned long used_0;
+                       /* there is at least 20 bytes left in the pack */
+                       switch (entry->in_pack_type) {
+                       case OBJ_REF_DELTA:
+                               base_name = use_pack(p, &w_curs,
+                                       entry->in_pack_offset + used, NULL);
+                               used += 20;
+                               break;
+                       case OBJ_OFS_DELTA:
+                               buf = use_pack(p, &w_curs,
+                                       entry->in_pack_offset + used, NULL);
+                               used_0 = 0;
+                               c = buf[used_0++];
+                               ofs = c & 127;
+                               while (c & 128) {
+                                       ofs += 1;
+                                       if (!ofs || ofs & ~(~0UL >> 7))
+                                               die("delta base offset overflow in pack for %s",
+                                                   sha1_to_hex(entry->sha1));
+                                       c = buf[used_0++];
+                                       ofs = (ofs << 7) + (c & 127);
+                               }
+                               if (ofs >= entry->in_pack_offset)
+                                       die("delta base offset out of bound for %s",
+                                           sha1_to_hex(entry->sha1));
+                               ofs = entry->in_pack_offset - ofs;
+                               base_name = find_packed_object_name(p, ofs);
+                               used += used_0;
+                               break;
+                       default:
+                               base_name = NULL;
+                       }
+                       if (base_name)
+                               base_entry = locate_object_entry(base_name);
+               }
+               unuse_pack(&w_curs);
+               entry->in_pack_header_size = used;
+
+               if (base_entry) {
 
                        /* Depth value does not matter - find_deltas()
                         * will never consider reused delta as the
@@ -927,9 +1050,9 @@ static void check_object(struct object_entry *entry)
                         */
 
                        /* uncompressed size of the delta data */
-                       entry->size = entry->delta_size = size;
+                       entry->size = size;
                        entry->delta = base_entry;
-                       entry->type = OBJ_DELTA;
+                       entry->type = entry->in_pack_type;
 
                        entry->delta_sibling = base_entry->delta_child;
                        base_entry->delta_child = entry;
@@ -1101,7 +1224,9 @@ static int try_delta(struct unpacked *trg, struct unpacked *src,
         * on an earlier try, but only when reusing delta data.
         */
        if (!no_reuse_delta && trg_entry->in_pack &&
-           trg_entry->in_pack == src_entry->in_pack)
+           trg_entry->in_pack == src_entry->in_pack &&
+           trg_entry->in_pack_type != OBJ_REF_DELTA &&
+           trg_entry->in_pack_type != OBJ_OFS_DELTA)
                return 0;
 
        /*
@@ -1450,10 +1575,6 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
                        local = 1;
                        continue;
                }
-               if (!strcmp("--progress", arg)) {
-                       progress = 1;
-                       continue;
-               }
                if (!strcmp("--incremental", arg)) {
                        incremental = 1;
                        continue;
@@ -1476,6 +1597,10 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
                        progress = 1;
                        continue;
                }
+               if (!strcmp("--all-progress", arg)) {
+                       progress = 2;
+                       continue;
+               }
                if (!strcmp("-q", arg)) {
                        progress = 0;
                        continue;
@@ -1484,6 +1609,10 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
                        no_reuse_delta = 1;
                        continue;
                }
+               if (!strcmp("--delta-base-offset", arg)) {
+                       allow_ofs_delta = 1;
+                       continue;
+               }
                if (!strcmp("--stdout", arg)) {
                        pack_to_stdout = 1;
                        continue;
@@ -1494,6 +1623,7 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
                }
                if (!strcmp("--unpacked", arg) ||
                    !strncmp("--unpacked=", arg, 11) ||
+                   !strcmp("--reflog", arg) ||
                    !strcmp("--all", arg)) {
                        use_internal_rev_list = 1;
                        if (ARRAY_SIZE(rp_av) - 1 <= rp_ac)
@@ -1567,7 +1697,7 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
        else {
                if (nr_result)
                        prepare_pack(window, depth);
-               if (progress && pack_to_stdout) {
+               if (progress == 1 && pack_to_stdout) {
                        /* the other end usually displays progress itself */
                        struct itimerval v = {{0,},};
                        setitimer(ITIMER_REAL, &v, NULL);
@@ -1581,7 +1711,7 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
                }
        }
        if (progress)
-               fprintf(stderr, "Total %d, written %d (delta %d), reused %d (delta %d)\n",
-                       nr_result, written, written_delta, reused, reused_delta);
+               fprintf(stderr, "Total %d (delta %d), reused %d (delta %d)\n",
+                       written, written_delta, reused, reused_delta);
        return 0;
 }