#include "cache.h"
#include "object.h"
-#include "blob.h"
-#include "commit.h"
-#include "tag.h"
-#include "tree.h"
-#include "delta.h"
#include "pack.h"
-#include "csum-file.h"
-#include "tree-walk.h"
-#include <sys/time.h>
-#include <signal.h>
+#include "pack-objects.h"
-static const char pack_usage[] = "git-pack-objects [-q] [--no-reuse-delta] [--non-empty] [--local] [--incremental] [--window=N] [--depth=N] {--stdout | base-name} < object-list";
-
-struct object_entry {
- unsigned char sha1[20];
- unsigned long size; /* uncompressed size */
- unsigned long offset; /* offset into the final pack file;
- * nonzero if already written.
- */
- unsigned int depth; /* delta depth */
- unsigned int delta_limit; /* base adjustment for in-pack delta */
- unsigned int hash; /* name hint hash */
- enum object_type type;
- enum object_type in_pack_type; /* could be delta */
- unsigned long delta_size; /* delta data size (uncompressed) */
- struct object_entry *delta; /* delta base object */
- struct packed_git *in_pack; /* already in pack */
- unsigned int in_pack_offset;
- struct object_entry *delta_child; /* delitified objects who bases me */
- struct object_entry *delta_sibling; /* other deltified objects who
- * uses the same base as me
- */
- int preferred_base; /* we do not pack this, but is encouraged to
- * be used as the base objectto delta huge
- * objects against.
- */
-};
-
-/*
- * Objects we are going to pack are colected in objects array (dynamically
- * expanded). nr_objects & nr_alloc controls this array. They are stored
- * in the order we see -- typically rev-list --objects order that gives us
- * nice "minimum seek" order.
- *
- * sorted-by-sha ans sorted-by-type are arrays of pointers that point at
- * elements in the objects array. The former is used to build the pack
- * index (lists object names in the ascending order to help offset lookup),
- * and the latter is used to group similar things together by try_delta()
- * heuristics.
- */
-
-static unsigned char object_list_sha1[20];
-static int non_empty = 0;
-static int no_reuse_delta = 0;
-static int local = 0;
-static int incremental = 0;
-static struct object_entry **sorted_by_sha, **sorted_by_type;
-static struct object_entry *objects = NULL;
-static int nr_objects = 0, nr_alloc = 0, nr_result = 0;
-static const char *base_name;
-static unsigned char pack_file_sha1[20];
-static int progress = 1;
-static volatile sig_atomic_t progress_update = 0;
-
-/*
- * The object names in objects array are hashed with this hashtable,
- * to help looking up the entry by object name. Binary search from
- * sorted_by_sha is also possible but this was easier to code and faster.
- * This hashtable is built after all the objects are seen.
- */
-static int *object_ix = NULL;
-static int object_ix_hashsz = 0;
-
-/*
- * 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.
- */
-struct pack_revindex {
- struct packed_git *p;
- unsigned long *revindex;
-} *pack_revindex = NULL;
-static int pack_revindex_hashsz = 0;
-
-/*
- * stats
- */
-static int written = 0;
-static int written_delta = 0;
-static int reused = 0;
-static int reused_delta = 0;
-
-static int pack_revindex_ix(struct packed_git *p)
-{
- unsigned long ui = (unsigned long)p;
- int i;
-
- ui = ui ^ (ui >> 16); /* defeat structure alignment */
- i = (int)(ui % pack_revindex_hashsz);
- while (pack_revindex[i].p) {
- if (pack_revindex[i].p == p)
- return i;
- if (++i == pack_revindex_hashsz)
- i = 0;
- }
- return -1 - i;
-}
-
-static void prepare_pack_ix(void)
-{
- int num;
- struct packed_git *p;
- for (num = 0, p = packed_git; p; p = p->next)
- num++;
- if (!num)
- return;
- pack_revindex_hashsz = num * 11;
- pack_revindex = xcalloc(sizeof(*pack_revindex), pack_revindex_hashsz);
- for (p = packed_git; p; p = p->next) {
- num = pack_revindex_ix(p);
- num = - 1 - num;
- pack_revindex[num].p = p;
- }
- /* revindex elements are lazily initialized */
-}
-
-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;
-}
-
-/*
- * Ordered list of offsets of objects in the pack.
- */
-static void prepare_pack_revindex(struct pack_revindex *rix)
-{
- struct packed_git *p = rix->p;
- int num_ent = num_packed_objects(p);
- int i;
- void *index = p->index_base + 256;
-
- rix->revindex = xmalloc(sizeof(unsigned long) * (num_ent + 1));
- for (i = 0; i < num_ent; i++) {
- unsigned int hl = *((unsigned int *)(index + 24 * i));
- rix->revindex[i] = ntohl(hl);
- }
- /* 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);
-}
-
-static unsigned long find_packed_object_size(struct packed_git *p,
- unsigned long ofs)
-{
- int num;
- int lo, hi;
- struct pack_revindex *rix;
- unsigned long *revindex;
- num = pack_revindex_ix(p);
- if (num < 0)
- die("internal error: pack revindex uninitialized");
- rix = &pack_revindex[num];
- if (!rix->revindex)
- prepare_pack_revindex(rix);
- revindex = rix->revindex;
- lo = 0;
- hi = num_packed_objects(p) + 1;
- do {
- int mi = (lo + hi) / 2;
- if (revindex[mi] == ofs) {
- return revindex[mi+1] - ofs;
- }
- else if (ofs < revindex[mi])
- hi = mi;
- else
- lo = mi + 1;
- } while (lo < hi);
- die("internal error: pack revindex corrupt");
-}
-
-static void *delta_against(void *buf, unsigned long size, struct object_entry *entry)
-{
- unsigned long othersize, delta_size;
- char type[10];
- void *otherbuf = read_sha1_file(entry->delta->sha1, type, &othersize);
- void *delta_buf;
-
- if (!otherbuf)
- die("unable to read %s", sha1_to_hex(entry->delta->sha1));
- delta_buf = diff_delta(otherbuf, othersize,
- buf, size, &delta_size, 0);
- if (!delta_buf || delta_size != entry->delta_size)
- die("delta size changed");
- free(buf);
- free(otherbuf);
- return delta_buf;
-}
-
-/*
- * The per-object header is a pretty dense thing, which is
- * - first byte: low four bits are "size", then three bits of "type",
- * and the high bit is "size continues".
- * - each byte afterwards: low seven bits are size continuation,
- * with the high bit being "size continues"
- */
-static int encode_header(enum object_type type, unsigned long size, unsigned char *hdr)
+static uint32_t locate_object_entry_hash(struct packing_data *pdata,
+ const unsigned char *sha1,
+ int *found)
{
- int n = 1;
- unsigned char c;
+ uint32_t i, hash, mask = (pdata->index_size - 1);
- if (type < OBJ_COMMIT || type > OBJ_DELTA)
- die("bad type %d", type);
+ memcpy(&hash, sha1, sizeof(uint32_t));
+ i = hash & mask;
- c = (type << 4) | (size & 15);
- size >>= 4;
- while (size) {
- *hdr++ = c | 0x80;
- c = size & 0x7f;
- size >>= 7;
- n++;
- }
- *hdr = c;
- return n;
-}
-
-static unsigned long write_object(struct sha1file *f,
- struct object_entry *entry)
-{
- unsigned long size;
- char type[10];
- void *buf;
- unsigned char header[10];
- unsigned hdrlen, datalen;
- enum object_type obj_type;
- int to_reuse = 0;
+ while (pdata->index[i] > 0) {
+ uint32_t pos = pdata->index[i] - 1;
- 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)
- 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 */
- else if (entry->delta)
- to_reuse = 0; /* we want to pack afresh */
- else
- to_reuse = 1; /* we have it in-pack undeltified,
- * and we do not need to deltify it.
- */
-
- if (! to_reuse) {
- buf = read_sha1_file(entry->sha1, type, &size);
- if (!buf)
- die("unable to read %s", sha1_to_hex(entry->sha1));
- if (size != entry->size)
- die("object %s size inconsistency (%lu vs %lu)",
- sha1_to_hex(entry->sha1), size, entry->size);
- if (entry->delta) {
- buf = delta_against(buf, size, entry);
- size = entry->delta_size;
- obj_type = OBJ_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.
- */
- hdrlen = encode_header(obj_type, size, header);
- sha1write(f, header, hdrlen);
-
- if (entry->delta) {
- sha1write(f, entry->delta, 20);
- hdrlen += 20;
- }
- datalen = sha1write_compressed(f, buf, size);
- free(buf);
- }
- else {
- struct packed_git *p = entry->in_pack;
- use_packed_git(p);
-
- datalen = find_packed_object_size(p, entry->in_pack_offset);
- buf = p->pack_base + entry->in_pack_offset;
- sha1write(f, buf, datalen);
- unuse_packed_git(p);
- hdrlen = 0; /* not really */
- if (obj_type == OBJ_DELTA)
- reused_delta++;
- reused++;
- }
- if (obj_type == OBJ_DELTA)
- written_delta++;
- written++;
- return hdrlen + datalen;
-}
-
-static unsigned long write_one(struct sha1file *f,
- struct object_entry *e,
- unsigned long offset)
-{
- if (e->offset)
- /* 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 (e->delta)
- offset = write_one(f, e->delta, offset);
- return offset;
-}
-
-static void write_pack_file(void)
-{
- int i;
- struct sha1file *f;
- unsigned long offset;
- struct pack_header hdr;
- unsigned last_percent = 999;
- int do_progress = 0;
-
- if (!base_name)
- f = sha1fd(1, "<stdout>");
- 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);
-
- hdr.hdr_signature = htonl(PACK_SIGNATURE);
- hdr.hdr_version = htonl(PACK_VERSION);
- hdr.hdr_entries = htonl(nr_result);
- sha1write(f, &hdr, sizeof(hdr));
- offset = sizeof(hdr);
- if (!nr_result)
- goto done;
- for (i = 0; i < nr_objects; i++) {
- offset = write_one(f, objects + i, offset);
- if (do_progress) {
- unsigned percent = written * 100 / nr_result;
- if (progress_update || percent != last_percent) {
- fprintf(stderr, "%4u%% (%u/%u) done\r",
- percent, written, nr_result);
- progress_update = 0;
- last_percent = percent;
- }
- }
- }
- if (do_progress)
- fputc('\n', stderr);
- done:
- sha1close(f, pack_file_sha1, 1);
-}
-
-static void write_index_file(void)
-{
- int i;
- struct sha1file *f = sha1create("%s-%s.%s", base_name,
- 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];
-
- /*
- * Write the first-level table (the list is sorted,
- * but we use a 256-entry lookup to be able to avoid
- * having to do eight extra binary search iterations).
- */
- for (i = 0; i < 256; i++) {
- struct object_entry **next = list;
- while (next < last) {
- struct object_entry *entry = *next;
- if (entry->sha1[0] != i)
- break;
- next++;
- }
- array[i] = htonl(next - sorted_by_sha);
- list = next;
- }
- sha1write(f, array, 256 * sizeof(int));
-
- /*
- * Write the actual SHA1 entries..
- */
- list = sorted_by_sha;
- for (i = 0; i < nr_result; i++) {
- struct object_entry *entry = *list++;
- unsigned int offset = htonl(entry->offset);
- sha1write(f, &offset, 4);
- sha1write(f, entry->sha1, 20);
- }
- sha1write(f, pack_file_sha1, 20);
- sha1close(f, NULL, 1);
-}
-
-static int locate_object_entry_hash(const unsigned char *sha1)
-{
- int i;
- unsigned int ui;
- memcpy(&ui, sha1, sizeof(unsigned int));
- i = ui % object_ix_hashsz;
- while (0 < object_ix[i]) {
- if (!memcmp(sha1, objects[object_ix[i]-1].sha1, 20))
+ if (!hashcmp(sha1, pdata->objects[pos].idx.sha1)) {
+ *found = 1;
return i;
- if (++i == object_ix_hashsz)
- i = 0;
- }
- return -1 - i;
-}
-
-static struct object_entry *locate_object_entry(const unsigned char *sha1)
-{
- int i;
-
- if (!object_ix_hashsz)
- return NULL;
-
- i = locate_object_entry_hash(sha1);
- if (0 <= i)
- return &objects[object_ix[i]-1];
- return NULL;
-}
-
-static void rehash_objects(void)
-{
- int i;
- struct object_entry *oe;
-
- object_ix_hashsz = nr_objects * 3;
- if (object_ix_hashsz < 1024)
- object_ix_hashsz = 1024;
- object_ix = xrealloc(object_ix, sizeof(int) * object_ix_hashsz);
- memset(object_ix, 0, sizeof(int) * object_ix_hashsz);
- for (i = 0, oe = objects; i < nr_objects; i++, oe++) {
- int ix = locate_object_entry_hash(oe->sha1);
- if (0 <= ix)
- continue;
- ix = -1 - ix;
- object_ix[ix] = i + 1;
- }
-}
-
-struct name_path {
- struct name_path *up;
- const char *elem;
- int len;
-};
-
-#define DIRBITS 12
-
-static unsigned name_hash(struct name_path *path, const char *name)
-{
- struct name_path *p = path;
- const char *n = name + strlen(name);
- unsigned hash = 0, name_hash = 0, name_done = 0;
-
- if (n != name && n[-1] == '\n')
- n--;
- while (name <= --n) {
- unsigned char c = *n;
- if (c == '/' && !name_done) {
- name_hash = hash;
- name_done = 1;
- hash = 0;
- }
- hash = hash * 11 + c;
- }
- if (!name_done) {
- name_hash = hash;
- hash = 0;
- }
- for (p = path; p; p = p->up) {
- hash = hash * 11 + '/';
- n = p->elem + p->len;
- while (p->elem <= --n) {
- unsigned char c = *n;
- hash = hash * 11 + c;
- }
- }
- /*
- * Make sure "Makefile" and "t/Makefile" are hashed separately
- * but close enough.
- */
- hash = (name_hash<<DIRBITS) | (hash & ((1U<<DIRBITS )-1));
- return hash;
-}
-
-static int add_object_entry(const unsigned char *sha1, unsigned hash, int exclude)
-{
- unsigned int idx = nr_objects;
- struct object_entry *entry;
- struct packed_git *p;
- unsigned int found_offset = 0;
- struct packed_git *found_pack = NULL;
- int ix, status = 0;
-
- if (!exclude) {
- for (p = packed_git; p; p = p->next) {
- struct pack_entry e;
- if (find_pack_entry_one(sha1, &e, p)) {
- if (incremental)
- return 0;
- if (local && !p->pack_local)
- return 0;
- if (!found_pack) {
- found_offset = e.offset;
- found_pack = e.p;
- }
- }
}
- }
- if ((entry = locate_object_entry(sha1)) != NULL)
- goto already_added;
- if (idx >= nr_alloc) {
- unsigned int needed = (idx + 1024) * 3 / 2;
- objects = xrealloc(objects, needed * sizeof(*entry));
- nr_alloc = needed;
- }
- entry = objects + idx;
- nr_objects = idx + 1;
- memset(entry, 0, sizeof(*entry));
- memcpy(entry->sha1, sha1, 20);
- entry->hash = hash;
-
- if (object_ix_hashsz * 3 <= nr_objects * 4)
- rehash_objects();
- else {
- ix = locate_object_entry_hash(entry->sha1);
- if (0 <= ix)
- die("internal error in object hashing.");
- object_ix[-1 - ix] = idx + 1;
- }
- status = 1;
-
- already_added:
- if (progress_update) {
- fprintf(stderr, "Counting objects...%d\r", nr_objects);
- progress_update = 0;
- }
- if (exclude)
- entry->preferred_base = 1;
- else {
- if (found_pack) {
- entry->in_pack = found_pack;
- entry->in_pack_offset = found_offset;
- }
- }
- return status;
-}
-
-struct pbase_tree_cache {
- unsigned char sha1[20];
- int ref;
- int temporary;
- void *tree_data;
- unsigned long tree_size;
-};
-
-static struct pbase_tree_cache *(pbase_tree_cache[256]);
-static int pbase_tree_cache_ix(const unsigned char *sha1)
-{
- return sha1[0] % ARRAY_SIZE(pbase_tree_cache);
-}
-static int pbase_tree_cache_ix_incr(int ix)
-{
- return (ix+1) % ARRAY_SIZE(pbase_tree_cache);
-}
-
-static struct pbase_tree {
- struct pbase_tree *next;
- /* This is a phony "cache" entry; we are not
- * going to evict it nor find it through _get()
- * mechanism -- this is for the toplevel node that
- * would almost always change with any commit.
- */
- struct pbase_tree_cache pcache;
-} *pbase_tree;
-
-static struct pbase_tree_cache *pbase_tree_get(const unsigned char *sha1)
-{
- struct pbase_tree_cache *ent, *nent;
- void *data;
- unsigned long size;
- char type[20];
- int neigh;
- int my_ix = pbase_tree_cache_ix(sha1);
- int available_ix = -1;
-
- /* pbase-tree-cache acts as a limited hashtable.
- * your object will be found at your index or within a few
- * slots after that slot if it is cached.
- */
- for (neigh = 0; neigh < 8; neigh++) {
- ent = pbase_tree_cache[my_ix];
- if (ent && !memcmp(ent->sha1, sha1, 20)) {
- ent->ref++;
- return ent;
- }
- else if (((available_ix < 0) && (!ent || !ent->ref)) ||
- ((0 <= available_ix) &&
- (!ent && pbase_tree_cache[available_ix])))
- available_ix = my_ix;
- if (!ent)
- break;
- my_ix = pbase_tree_cache_ix_incr(my_ix);
- }
-
- /* Did not find one. Either we got a bogus request or
- * we need to read and perhaps cache.
- */
- data = read_sha1_file(sha1, type, &size);
- if (!data)
- return NULL;
- if (strcmp(type, tree_type)) {
- free(data);
- return NULL;
- }
-
- /* We need to either cache or return a throwaway copy */
-
- if (available_ix < 0)
- ent = NULL;
- else {
- ent = pbase_tree_cache[available_ix];
- my_ix = available_ix;
- }
-
- if (!ent) {
- nent = xmalloc(sizeof(*nent));
- nent->temporary = (available_ix < 0);
- }
- else {
- /* evict and reuse */
- free(ent->tree_data);
- nent = ent;
- }
- memcpy(nent->sha1, sha1, 20);
- nent->tree_data = data;
- nent->tree_size = size;
- nent->ref = 1;
- if (!nent->temporary)
- pbase_tree_cache[my_ix] = nent;
- return nent;
-}
-
-static void pbase_tree_put(struct pbase_tree_cache *cache)
-{
- if (!cache->temporary) {
- cache->ref--;
- return;
+ i = (i + 1) & mask;
}
- free(cache->tree_data);
- free(cache);
-}
-static int name_cmp_len(const char *name)
-{
- int i;
- for (i = 0; name[i] && name[i] != '\n' && name[i] != '/'; i++)
- ;
+ *found = 0;
return i;
}
-static void add_pbase_object(struct tree_desc *tree,
- struct name_path *up,
- const char *name,
- int cmplen)
-{
- while (tree->size) {
- const unsigned char *sha1;
- const char *entry_name;
- int entry_len;
- unsigned mode;
- unsigned long size;
- char type[20];
-
- sha1 = tree_entry_extract(tree, &entry_name, &mode);
- update_tree_entry(tree);
- entry_len = strlen(entry_name);
- if (entry_len != cmplen ||
- memcmp(entry_name, name, cmplen) ||
- !has_sha1_file(sha1) ||
- sha1_object_info(sha1, type, &size))
- continue;
- if (name[cmplen] != '/') {
- unsigned hash = name_hash(up, name);
- add_object_entry(sha1, hash, 1);
- return;
- }
- if (!strcmp(type, tree_type)) {
- struct tree_desc sub;
- struct name_path me;
- struct pbase_tree_cache *tree;
- const char *down = name+cmplen+1;
- int downlen = name_cmp_len(down);
-
- tree = pbase_tree_get(sha1);
- if (!tree)
- return;
- sub.buf = tree->tree_data;
- sub.size = tree->tree_size;
-
- me.up = up;
- me.elem = entry_name;
- me.len = entry_len;
- add_pbase_object(&sub, &me, down, downlen);
- pbase_tree_put(tree);
- }
- }
-}
-
-static unsigned *done_pbase_paths;
-static int done_pbase_paths_num;
-static int done_pbase_paths_alloc;
-static int done_pbase_path_pos(unsigned hash)
-{
- int lo = 0;
- int hi = done_pbase_paths_num;
- while (lo < hi) {
- int mi = (hi + lo) / 2;
- if (done_pbase_paths[mi] == hash)
- return mi;
- if (done_pbase_paths[mi] < hash)
- hi = mi;
- else
- lo = mi + 1;
- }
- return -lo-1;
-}
-
-static int check_pbase_path(unsigned hash)
-{
- int pos = (!done_pbase_paths) ? -1 : done_pbase_path_pos(hash);
- if (0 <= pos)
- return 1;
- pos = -pos - 1;
- if (done_pbase_paths_alloc <= done_pbase_paths_num) {
- done_pbase_paths_alloc = alloc_nr(done_pbase_paths_alloc);
- done_pbase_paths = xrealloc(done_pbase_paths,
- done_pbase_paths_alloc *
- sizeof(unsigned));
- }
- done_pbase_paths_num++;
- if (pos < done_pbase_paths_num)
- memmove(done_pbase_paths + pos + 1,
- done_pbase_paths + pos,
- (done_pbase_paths_num - pos - 1) * sizeof(unsigned));
- done_pbase_paths[pos] = hash;
- return 0;
-}
-
-static void add_preferred_base_object(char *name, unsigned hash)
-{
- struct pbase_tree *it;
- int cmplen = name_cmp_len(name);
-
- if (check_pbase_path(hash))
- return;
-
- for (it = pbase_tree; it; it = it->next) {
- if (cmplen == 0) {
- hash = name_hash(NULL, "");
- add_object_entry(it->pcache.sha1, hash, 1);
- }
- else {
- struct tree_desc tree;
- tree.buf = it->pcache.tree_data;
- tree.size = it->pcache.tree_size;
- add_pbase_object(&tree, NULL, name, cmplen);
- }
- }
-}
-
-static void add_preferred_base(unsigned char *sha1)
-{
- struct pbase_tree *it;
- void *data;
- unsigned long size;
- unsigned char tree_sha1[20];
-
- data = read_object_with_reference(sha1, tree_type, &size, tree_sha1);
- if (!data)
- return;
-
- for (it = pbase_tree; it; it = it->next) {
- if (!memcmp(it->pcache.sha1, tree_sha1, 20)) {
- free(data);
- return;
- }
- }
-
- it = xcalloc(1, sizeof(*it));
- it->next = pbase_tree;
- pbase_tree = it;
-
- memcpy(it->pcache.sha1, tree_sha1, 20);
- it->pcache.tree_data = data;
- it->pcache.tree_size = size;
-}
-
-static void check_object(struct object_entry *entry)
+static inline uint32_t closest_pow2(uint32_t v)
{
- char type[20];
-
- if (entry->in_pack && !entry->preferred_base) {
- unsigned char base[20];
- unsigned long size;
- struct object_entry *base_entry;
-
- /* 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);
-
- /* 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)) {
-
- /* Depth value does not matter - find_deltas()
- * will never consider reused delta as the
- * base object to deltify other objects
- * against, in order to avoid circular deltas.
- */
-
- /* uncompressed size of the delta data */
- entry->size = entry->delta_size = size;
- entry->delta = base_entry;
- entry->type = OBJ_DELTA;
-
- entry->delta_sibling = base_entry->delta_child;
- base_entry->delta_child = entry;
-
- return;
- }
- /* Otherwise we would do the usual */
- }
-
- if (sha1_object_info(entry->sha1, type, &entry->size))
- die("unable to get type of object %s",
- sha1_to_hex(entry->sha1));
-
- if (!strcmp(type, commit_type)) {
- entry->type = OBJ_COMMIT;
- } else if (!strcmp(type, tree_type)) {
- entry->type = OBJ_TREE;
- } else if (!strcmp(type, blob_type)) {
- entry->type = OBJ_BLOB;
- } else if (!strcmp(type, tag_type)) {
- entry->type = OBJ_TAG;
- } else
- die("unable to pack object %s of type %s",
- sha1_to_hex(entry->sha1), type);
+ v = v - 1;
+ v |= v >> 1;
+ v |= v >> 2;
+ v |= v >> 4;
+ v |= v >> 8;
+ v |= v >> 16;
+ return v + 1;
}
-static unsigned int check_delta_limit(struct object_entry *me, unsigned int n)
+static void rehash_objects(struct packing_data *pdata)
{
- struct object_entry *child = me->delta_child;
- unsigned int m = n;
- while (child) {
- unsigned int c = check_delta_limit(child, n + 1);
- if (m < c)
- m = c;
- child = child->delta_sibling;
- }
- return m;
-}
-
-static void get_object_details(void)
-{
- int i;
+ uint32_t i;
struct object_entry *entry;
- prepare_pack_ix();
- for (i = 0, entry = objects; i < nr_objects; i++, entry++)
- check_object(entry);
-
- if (nr_objects == nr_result) {
- /*
- * Depth of objects that depend on the entry -- this
- * is subtracted from depth-max to break too deep
- * delta chain because of delta data reusing.
- * However, we loosen this restriction when we know we
- * are creating a thin pack -- it will have to be
- * expanded on the other end anyway, so do not
- * artificially cut the delta chain and let it go as
- * deep as it wants.
- */
- for (i = 0, entry = objects; i < nr_objects; i++, entry++)
- if (!entry->delta && entry->delta_child)
- entry->delta_limit =
- check_delta_limit(entry, 1);
- }
-}
-
-typedef int (*entry_sort_t)(const struct object_entry *, const struct object_entry *);
-
-static entry_sort_t current_sort;
-
-static int sort_comparator(const void *_a, const void *_b)
-{
- struct object_entry *a = *(struct object_entry **)_a;
- struct object_entry *b = *(struct object_entry **)_b;
- return current_sort(a,b);
-}
+ pdata->index_size = closest_pow2(pdata->nr_objects * 3);
+ if (pdata->index_size < 1024)
+ pdata->index_size = 1024;
-static struct object_entry **create_sorted_list(entry_sort_t sort)
-{
- struct object_entry **list = xmalloc(nr_objects * sizeof(struct object_entry *));
- int i;
+ pdata->index = xrealloc(pdata->index, sizeof(uint32_t) * pdata->index_size);
+ memset(pdata->index, 0, sizeof(int) * pdata->index_size);
- for (i = 0; i < nr_objects; i++)
- list[i] = objects + i;
- current_sort = sort;
- qsort(list, nr_objects, sizeof(struct object_entry *), sort_comparator);
- return list;
-}
+ entry = pdata->objects;
-static int sha1_sort(const struct object_entry *a, const struct object_entry *b)
-{
- return memcmp(a->sha1, b->sha1, 20);
-}
+ for (i = 0; i < pdata->nr_objects; i++) {
+ int found;
+ uint32_t ix = locate_object_entry_hash(pdata, entry->idx.sha1, &found);
-static struct object_entry **create_final_object_list(void)
-{
- struct object_entry **list;
- int i, j;
+ if (found)
+ die("BUG: Duplicate object in hash");
- for (i = nr_result = 0; i < nr_objects; i++)
- if (!objects[i].preferred_base)
- nr_result++;
- list = xmalloc(nr_result * sizeof(struct object_entry *));
- for (i = j = 0; i < nr_objects; i++) {
- if (!objects[i].preferred_base)
- list[j++] = objects + i;
+ pdata->index[ix] = i + 1;
+ entry++;
}
- current_sort = sha1_sort;
- qsort(list, nr_result, sizeof(struct object_entry *), sort_comparator);
- return list;
}
-static int type_size_sort(const struct object_entry *a, const struct object_entry *b)
+struct object_entry *packlist_find(struct packing_data *pdata,
+ const unsigned char *sha1,
+ uint32_t *index_pos)
{
- if (a->type < b->type)
- return -1;
- if (a->type > b->type)
- return 1;
- if (a->hash < b->hash)
- return -1;
- if (a->hash > b->hash)
- return 1;
- if (a->preferred_base < b->preferred_base)
- return -1;
- if (a->preferred_base > b->preferred_base)
- return 1;
- if (a->size < b->size)
- return -1;
- if (a->size > b->size)
- return 1;
- return a < b ? -1 : (a > b);
-}
+ uint32_t i;
+ int found;
-struct unpacked {
- struct object_entry *entry;
- void *data;
- struct delta_index *index;
-};
-
-/*
- * We search for deltas _backwards_ in a list sorted by type and
- * by size, so that we see progressively smaller and smaller files.
- * That's because we prefer deltas to be from the bigger file
- * to the smaller - deletes are potentially cheaper, but perhaps
- * more importantly, the bigger file is likely the more recent
- * one.
- */
-static int try_delta(struct unpacked *trg, struct unpacked *src,
- struct delta_index *src_index, unsigned max_depth)
-{
- struct object_entry *trg_entry = trg->entry;
- struct object_entry *src_entry = src->entry;
- unsigned long size, src_size, delta_size, sizediff, max_size;
- void *delta_buf;
-
- /* Don't bother doing diffs between different types */
- if (trg_entry->type != src_entry->type)
- return -1;
-
- /* We do not compute delta to *create* objects we are not
- * going to pack.
- */
- if (trg_entry->preferred_base)
- return -1;
-
- /*
- * If the current object is at pack edge, take the depth the
- * objects that depend on the current object into account --
- * otherwise they would become too deep.
- */
- if (trg_entry->delta_child) {
- if (max_depth <= trg_entry->delta_limit)
- return 0;
- max_depth -= trg_entry->delta_limit;
- }
- if (src_entry->depth >= max_depth)
- return 0;
-
- /* Now some size filtering heuristics. */
- size = trg_entry->size;
- max_size = size/2 - 20;
- max_size = max_size * (max_depth - src_entry->depth) / max_depth;
- if (max_size == 0)
- return 0;
- if (trg_entry->delta && trg_entry->delta_size <= max_size)
- max_size = trg_entry->delta_size-1;
- src_size = src_entry->size;
- sizediff = src_size < size ? size - src_size : 0;
- if (sizediff >= max_size)
- return 0;
-
- delta_buf = create_delta(src_index, trg->data, size, &delta_size, max_size);
- if (!delta_buf)
- return 0;
-
- trg_entry->delta = src_entry;
- trg_entry->delta_size = delta_size;
- trg_entry->depth = src_entry->depth + 1;
- free(delta_buf);
- return 1;
-}
-
-static void progress_interval(int signum)
-{
- progress_update = 1;
-}
-
-static void find_deltas(struct object_entry **list, int window, int depth)
-{
- int i, idx;
- unsigned int array_size = window * sizeof(struct unpacked);
- struct unpacked *array = xmalloc(array_size);
- unsigned processed = 0;
- unsigned last_percent = 999;
-
- memset(array, 0, array_size);
- i = nr_objects;
- idx = 0;
- if (progress)
- fprintf(stderr, "Deltifying %d objects.\n", nr_result);
-
- while (--i >= 0) {
- struct object_entry *entry = list[i];
- struct unpacked *n = array + idx;
- unsigned long size;
- char type[10];
- int j;
-
- if (!entry->preferred_base)
- processed++;
-
- if (progress) {
- unsigned percent = processed * 100 / nr_result;
- if (percent != last_percent || progress_update) {
- fprintf(stderr, "%4u%% (%u/%u) done\r",
- percent, processed, nr_result);
- progress_update = 0;
- last_percent = percent;
- }
- }
-
- if (entry->delta)
- /* This happens if we decided to reuse existing
- * delta from a pack. "!no_reuse_delta &&" is implied.
- */
- continue;
-
- if (entry->size < 50)
- continue;
- free_delta_index(n->index);
- n->index = NULL;
- free(n->data);
- n->entry = entry;
- n->data = read_sha1_file(entry->sha1, type, &size);
- if (size != entry->size)
- die("object %s inconsistent object length (%lu vs %lu)",
- sha1_to_hex(entry->sha1), size, entry->size);
-
- j = window;
- while (--j > 0) {
- unsigned int other_idx = idx + j;
- struct unpacked *m;
- if (other_idx >= window)
- other_idx -= window;
- m = array + other_idx;
- if (!m->entry)
- break;
- if (try_delta(n, m, m->index, depth) < 0)
- break;
- }
- /* if we made n a delta, and if n is already at max
- * depth, leaving it in the window is pointless. we
- * should evict it first.
- */
- if (entry->delta && depth <= entry->depth)
- continue;
-
- n->index = create_delta_index(n->data, size);
- if (!n->index)
- die("out of memory");
-
- idx++;
- if (idx >= window)
- idx = 0;
- }
-
- if (progress)
- fputc('\n', stderr);
-
- for (i = 0; i < window; ++i) {
- free_delta_index(array[i].index);
- free(array[i].data);
- }
- free(array);
-}
-
-static void prepare_pack(int window, int depth)
-{
- get_object_details();
- sorted_by_type = create_sorted_list(type_size_sort);
- if (window && depth)
- find_deltas(sorted_by_type, window+1, depth);
-}
-
-static int reuse_cached_pack(unsigned char *sha1, int pack_to_stdout)
-{
- static const char cache[] = "pack-cache/pack-%s.%s";
- char *cached_pack, *cached_idx;
- int ifd, ofd, ifd_ix = -1;
-
- cached_pack = git_path(cache, sha1_to_hex(sha1), "pack");
- ifd = open(cached_pack, O_RDONLY);
- if (ifd < 0)
- return 0;
-
- if (!pack_to_stdout) {
- cached_idx = git_path(cache, sha1_to_hex(sha1), "idx");
- ifd_ix = open(cached_idx, O_RDONLY);
- if (ifd_ix < 0) {
- close(ifd);
- return 0;
- }
- }
-
- if (progress)
- fprintf(stderr, "Reusing %d objects pack %s\n", nr_objects,
- sha1_to_hex(sha1));
-
- if (pack_to_stdout) {
- if (copy_fd(ifd, 1))
- exit(1);
- close(ifd);
- }
- else {
- char name[PATH_MAX];
- snprintf(name, sizeof(name),
- "%s-%s.%s", base_name, sha1_to_hex(sha1), "pack");
- ofd = open(name, O_CREAT | O_EXCL | O_WRONLY, 0666);
- if (ofd < 0)
- die("unable to open %s (%s)", name, strerror(errno));
- if (copy_fd(ifd, ofd))
- exit(1);
- close(ifd);
-
- snprintf(name, sizeof(name),
- "%s-%s.%s", base_name, sha1_to_hex(sha1), "idx");
- ofd = open(name, O_CREAT | O_EXCL | O_WRONLY, 0666);
- if (ofd < 0)
- die("unable to open %s (%s)", name, strerror(errno));
- if (copy_fd(ifd_ix, ofd))
- exit(1);
- close(ifd_ix);
- puts(sha1_to_hex(sha1));
- }
+ if (!pdata->index_size)
+ return NULL;
- return 1;
-}
+ i = locate_object_entry_hash(pdata, sha1, &found);
-static void setup_progress_signal(void)
-{
- struct sigaction sa;
- struct itimerval v;
+ if (index_pos)
+ *index_pos = i;
- memset(&sa, 0, sizeof(sa));
- sa.sa_handler = progress_interval;
- sigemptyset(&sa.sa_mask);
- sa.sa_flags = SA_RESTART;
- sigaction(SIGALRM, &sa, NULL);
+ if (!found)
+ return NULL;
- v.it_interval.tv_sec = 1;
- v.it_interval.tv_usec = 0;
- v.it_value = v.it_interval;
- setitimer(ITIMER_REAL, &v, NULL);
+ return &pdata->objects[pdata->index[i] - 1];
}
-int main(int argc, char **argv)
+struct object_entry *packlist_alloc(struct packing_data *pdata,
+ const unsigned char *sha1,
+ uint32_t index_pos)
{
- SHA_CTX ctx;
- char line[40 + 1 + PATH_MAX + 2];
- int window = 10, depth = 10, pack_to_stdout = 0;
- struct object_entry **list;
- int num_preferred_base = 0;
- int i;
+ struct object_entry *new_entry;
- setup_git_directory();
-
- progress = isatty(2);
- for (i = 1; i < argc; i++) {
- const char *arg = argv[i];
-
- if (*arg == '-') {
- if (!strcmp("--non-empty", arg)) {
- non_empty = 1;
- continue;
- }
- if (!strcmp("--local", arg)) {
- local = 1;
- continue;
- }
- if (!strcmp("--incremental", arg)) {
- incremental = 1;
- continue;
- }
- if (!strncmp("--window=", arg, 9)) {
- char *end;
- window = strtoul(arg+9, &end, 0);
- if (!arg[9] || *end)
- usage(pack_usage);
- continue;
- }
- if (!strncmp("--depth=", arg, 8)) {
- char *end;
- depth = strtoul(arg+8, &end, 0);
- if (!arg[8] || *end)
- usage(pack_usage);
- continue;
- }
- if (!strcmp("--progress", arg)) {
- progress = 1;
- continue;
- }
- if (!strcmp("-q", arg)) {
- progress = 0;
- continue;
- }
- if (!strcmp("--no-reuse-delta", arg)) {
- no_reuse_delta = 1;
- continue;
- }
- if (!strcmp("--stdout", arg)) {
- pack_to_stdout = 1;
- continue;
- }
- usage(pack_usage);
- }
- if (base_name)
- usage(pack_usage);
- base_name = arg;
- }
-
- if (pack_to_stdout != !base_name)
- usage(pack_usage);
-
- prepare_packed_git();
-
- if (progress) {
- fprintf(stderr, "Generating pack...\n");
- setup_progress_signal();
+ if (pdata->nr_objects >= pdata->nr_alloc) {
+ pdata->nr_alloc = (pdata->nr_alloc + 1024) * 3 / 2;
+ pdata->objects = xrealloc(pdata->objects,
+ pdata->nr_alloc * sizeof(*new_entry));
}
- for (;;) {
- unsigned char sha1[20];
- unsigned hash;
-
- if (!fgets(line, sizeof(line), stdin)) {
- if (feof(stdin))
- break;
- if (!ferror(stdin))
- die("fgets returned NULL, not EOF, not error!");
- if (errno != EINTR)
- die("fgets: %s", strerror(errno));
- clearerr(stdin);
- continue;
- }
+ new_entry = pdata->objects + pdata->nr_objects++;
- if (line[0] == '-') {
- if (get_sha1_hex(line+1, sha1))
- die("expected edge sha1, got garbage:\n %s",
- line+1);
- if (num_preferred_base++ < window)
- add_preferred_base(sha1);
- continue;
- }
- if (get_sha1_hex(line, sha1))
- die("expected sha1, got garbage:\n %s", line);
- hash = name_hash(NULL, line+41);
- add_preferred_base_object(line+41, hash);
- add_object_entry(sha1, hash, 0);
- }
- if (progress)
- fprintf(stderr, "Done counting %d objects.\n", nr_objects);
- sorted_by_sha = create_final_object_list();
- if (non_empty && !nr_result)
- return 0;
+ memset(new_entry, 0, sizeof(*new_entry));
+ hashcpy(new_entry->idx.sha1, sha1);
- SHA1_Init(&ctx);
- list = sorted_by_sha;
- for (i = 0; i < nr_result; i++) {
- struct object_entry *entry = *list++;
- SHA1_Update(&ctx, entry->sha1, 20);
- }
- SHA1_Final(object_list_sha1, &ctx);
- if (progress && (nr_objects != nr_result))
- fprintf(stderr, "Result has %d objects.\n", nr_result);
+ if (pdata->index_size * 3 <= pdata->nr_objects * 4)
+ rehash_objects(pdata);
+ else
+ pdata->index[index_pos] = pdata->nr_objects;
- if (reuse_cached_pack(object_list_sha1, pack_to_stdout))
- ;
- else {
- if (nr_result)
- prepare_pack(window, depth);
- if (progress && pack_to_stdout) {
- /* the other end usually displays progress itself */
- struct itimerval v = {{0,},};
- setitimer(ITIMER_REAL, &v, NULL);
- signal(SIGALRM, SIG_IGN );
- progress_update = 0;
- }
- write_pack_file();
- if (!pack_to_stdout) {
- write_index_file();
- puts(sha1_to_hex(object_list_sha1));
- }
- }
- if (progress)
- fprintf(stderr, "Total %d, written %d (delta %d), reused %d (delta %d)\n",
- nr_result, written, written_delta, reused, reused_delta);
- return 0;
+ return new_entry;
}