git/builtin-pack-objects.c
Linus Torvalds 6fda5e5180 Initialize tree descriptors with a helper function rather than by hand.
This removes slightly more lines than it adds, but the real reason for
doing this is that future optimizations will require more setup of the
tree descriptor, and so we want to do it in one place.

Also renamed the "desc.buf" field to "desc.buffer" just to trigger
compiler errors for old-style manual initializations, making sure I
didn't miss anything.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-03-21 10:21:57 -07:00

1707 lines
42 KiB
C

#include "builtin.h"
#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 "diff.h"
#include "revision.h"
#include "list-objects.h"
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];
unsigned long size; /* uncompressed size */
off_t 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) */
#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 */
off_t in_pack_offset;
struct object_entry *delta_child; /* deltified 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 collected 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;
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 uint32_t nr_objects, nr_alloc, nr_result;
static const char *base_name;
static unsigned char pack_file_sha1[20];
static int progress = 1;
static volatile sig_atomic_t progress_update;
static int window = 10;
static int pack_to_stdout;
static int num_preferred_base;
/*
* 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;
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). 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 {
off_t offset;
unsigned int nr;
};
struct pack_revindex {
struct packed_git *p;
struct revindex_entry *revindex;
};
static struct pack_revindex *pack_revindex;
static int pack_revindex_hashsz;
/*
* stats
*/
static uint32_t written, written_delta;
static uint32_t reused, reused_delta;
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_)
{
const struct revindex_entry *a = a_;
const struct revindex_entry *b = b_;
return (a->offset < b->offset) ? -1 : (a->offset > b->offset) ? 1 : 0;
}
/*
* 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;
const char *index = p->index_data;
index += 4 * 256;
rix->revindex = xmalloc(sizeof(*rix->revindex) * (num_ent + 1));
for (i = 0; i < num_ent; i++) {
uint32_t hl = *((uint32_t *)(index + 24 * i));
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].offset = p->pack_size - 20;
rix->revindex[num_ent].nr = -1;
qsort(rix->revindex, num_ent, sizeof(*rix->revindex), cmp_offset);
}
static struct revindex_entry * find_packed_object(struct packed_git *p,
off_t ofs)
{
int num;
int lo, hi;
struct pack_revindex *rix;
struct revindex_entry *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].offset == ofs) {
return revindex + mi;
}
else if (ofs < revindex[mi].offset)
hi = mi;
else
lo = mi + 1;
} while (lo < hi);
die("internal error: pack revindex corrupt");
}
static off_t find_packed_object_size(struct packed_git *p, off_t ofs)
{
struct revindex_entry *entry = find_packed_object(p, ofs);
return entry[1].offset - ofs;
}
static const unsigned char *find_packed_object_name(struct packed_git *p,
off_t ofs)
{
struct revindex_entry *entry = find_packed_object(p, ofs);
return ((unsigned char *)p->index_data) + 4 * 256 + 24 * entry->nr + 4;
}
static void *delta_against(void *buf, unsigned long size, struct object_entry *entry)
{
unsigned long othersize, delta_size;
enum object_type type;
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)
{
int n = 1;
unsigned char c;
if (type < OBJ_COMMIT || type > OBJ_REF_DELTA)
die("bad type %d", type);
c = (type << 4) | (size & 15);
size >>= 4;
while (size) {
*hdr++ = c | 0x80;
c = size & 0x7f;
size >>= 7;
n++;
}
*hdr = c;
return n;
}
/*
* 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,
off_t offset,
off_t 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,
off_t offset,
off_t len)
{
unsigned char *in;
unsigned int avail;
while (len) {
in = use_pack(p, w_curs, offset, &avail);
if (avail > len)
avail = (unsigned int)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];
int st;
memset(&stream, 0, sizeof(stream));
stream.next_in = data;
stream.avail_in = len;
stream.next_out = fakebuf;
stream.avail_out = sizeof(fakebuf);
inflateInit(&stream);
while (1) {
st = inflate(&stream, Z_FINISH);
if (st == Z_STREAM_END || st == Z_OK) {
st = (stream.total_out == expect &&
stream.total_in == len) ? 0 : -1;
break;
}
if (st != Z_BUF_ERROR) {
st = -1;
break;
}
stream.next_out = fakebuf;
stream.avail_out = sizeof(fakebuf);
}
inflateEnd(&stream);
return st;
}
static int revalidate_loose_object(struct object_entry *entry,
unsigned char *map,
unsigned long mapsize)
{
/* we already know this is a loose object with new type header. */
enum object_type type;
unsigned long size, used;
if (pack_to_stdout)
return 0;
used = unpack_object_header_gently(map, mapsize, &type, &size);
if (!used)
return -1;
map += used;
mapsize -= used;
return check_loose_inflate(map, mapsize, size);
}
static off_t write_object(struct sha1file *f,
struct object_entry *entry)
{
unsigned long size;
enum object_type type;
void *buf;
unsigned char header[10];
unsigned hdrlen;
off_t datalen;
enum object_type obj_type;
int to_reuse = 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_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 */
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 (!entry->in_pack && !entry->delta) {
unsigned char *map;
unsigned long mapsize;
map = map_sha1_file(entry->sha1, &mapsize);
if (map && !legacy_loose_object(map)) {
/* We can copy straight into the pack file */
if (revalidate_loose_object(entry, map, mapsize))
die("corrupt loose object %s",
sha1_to_hex(entry->sha1));
sha1write(f, map, mapsize);
munmap(map, mapsize);
written++;
reused++;
return mapsize;
}
if (map)
munmap(map, mapsize);
}
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 = (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.
*/
hdrlen = encode_header(obj_type, size, header);
sha1write(f, header, hdrlen);
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.
*/
off_t 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);
free(buf);
}
else {
struct packed_git *p = entry->in_pack;
struct pack_window *w_curs = NULL;
off_t 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) {
off_t 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;
}
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));
copy_pack_data(f, p, &w_curs, offset, datalen);
unuse_pack(&w_curs);
reused++;
}
if (entry->delta)
written_delta++;
written++;
return hdrlen + datalen;
}
static off_t write_one(struct sha1file *f,
struct object_entry *e,
off_t offset)
{
if (e->offset || e->preferred_base)
/* offset starts from header size and cannot be zero
* if it is written already.
*/
return offset;
/* if we are deltified, write out its base object first. */
if (e->delta)
offset = write_one(f, e->delta, offset);
e->offset = offset;
return offset + write_object(f, e);
}
static void write_pack_file(void)
{
uint32_t i;
struct sha1file *f;
off_t offset;
struct pack_header hdr;
unsigned last_percent = 999;
int do_progress = progress;
if (!base_name) {
f = sha1fd(1, "<stdout>");
do_progress >>= 1;
}
else
f = sha1create("%s-%s.%s", base_name,
sha1_to_hex(object_list_sha1), "pack");
if (do_progress)
fprintf(stderr, "Writing %u 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:
if (written != nr_result)
die("wrote %u objects while expecting %u", written, nr_result);
sha1close(f, pack_file_sha1, 1);
}
static void write_index_file(void)
{
uint32_t 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;
uint32_t 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 * 4);
/*
* Write the actual SHA1 entries..
*/
list = sorted_by_sha;
for (i = 0; i < nr_result; i++) {
struct object_entry *entry = *list++;
uint32_t 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 (!hashcmp(sha1, objects[object_ix[i] - 1].sha1))
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)
{
uint32_t 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;
}
}
static unsigned name_hash(const char *name)
{
unsigned char c;
unsigned hash = 0;
/*
* This effectively just creates a sortable number from the
* last sixteen non-whitespace characters. Last characters
* count "most", so things that end in ".c" sort together.
*/
while ((c = *name++) != 0) {
if (isspace(c))
continue;
hash = (hash >> 2) + (c << 24);
}
return hash;
}
static int add_object_entry(const unsigned char *sha1, unsigned hash, int exclude)
{
uint32_t idx = nr_objects;
struct object_entry *entry;
struct packed_git *p;
off_t found_offset = 0;
struct packed_git *found_pack = NULL;
int ix, status = 0;
if (!exclude) {
for (p = packed_git; p; p = p->next) {
off_t offset = find_pack_entry_one(sha1, p);
if (offset) {
if (incremental)
return 0;
if (local && !p->pack_local)
return 0;
if (!found_pack) {
found_offset = offset;
found_pack = p;
}
}
}
}
if ((entry = locate_object_entry(sha1)) != NULL)
goto already_added;
if (idx >= nr_alloc) {
nr_alloc = (idx + 1024) * 3 / 2;
objects = xrealloc(objects, nr_alloc * sizeof(*entry));
}
entry = objects + idx;
nr_objects = idx + 1;
memset(entry, 0, sizeof(*entry));
hashcpy(entry->sha1, sha1);
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...%u\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;
enum object_type type;
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 && !hashcmp(ent->sha1, sha1)) {
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 (type != OBJ_TREE) {
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;
}
hashcpy(nent->sha1, sha1);
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;
}
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++)
;
return i;
}
static void add_pbase_object(struct tree_desc *tree,
const char *name,
int cmplen,
const char *fullname)
{
struct name_entry entry;
while (tree_entry(tree,&entry)) {
unsigned long size;
enum object_type type;
if (tree_entry_len(entry.path, entry.sha1) != cmplen ||
memcmp(entry.path, name, cmplen) ||
!has_sha1_file(entry.sha1) ||
(type = sha1_object_info(entry.sha1, &size)) < 0)
continue;
if (name[cmplen] != '/') {
unsigned hash = name_hash(fullname);
add_object_entry(entry.sha1, hash, 1);
return;
}
if (type == OBJ_TREE) {
struct tree_desc sub;
struct pbase_tree_cache *tree;
const char *down = name+cmplen+1;
int downlen = name_cmp_len(down);
tree = pbase_tree_get(entry.sha1);
if (!tree)
return;
init_tree_desc(&sub, tree->tree_data, tree->tree_size);
add_pbase_object(&sub, down, downlen, fullname);
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(const 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("");
add_object_entry(it->pcache.sha1, hash, 1);
}
else {
struct tree_desc tree;
init_tree_desc(&tree, it->pcache.tree_data, it->pcache.tree_size);
add_pbase_object(&tree, name, cmplen, name);
}
}
}
static void add_preferred_base(unsigned char *sha1)
{
struct pbase_tree *it;
void *data;
unsigned long size;
unsigned char tree_sha1[20];
if (window <= num_preferred_base++)
return;
data = read_object_with_reference(sha1, tree_type, &size, tree_sha1);
if (!data)
return;
for (it = pbase_tree; it; it = it->next) {
if (!hashcmp(it->pcache.sha1, tree_sha1)) {
free(data);
return;
}
}
it = xcalloc(1, sizeof(*it));
it->next = pbase_tree;
pbase_tree = it;
hashcpy(it->pcache.sha1, tree_sha1);
it->pcache.tree_data = data;
it->pcache.tree_size = size;
}
static void check_object(struct object_entry *entry)
{
if (entry->in_pack && !entry->preferred_base) {
struct packed_git *p = entry->in_pack;
struct pack_window *w_curs = NULL;
unsigned long size, used;
unsigned int avail;
unsigned char *buf;
struct object_entry *base_entry = NULL;
buf = use_pack(p, &w_curs, entry->in_pack_offset, &avail);
/* We want in_pack_type even if we do not reuse delta.
* There is no point not reusing non-delta representations.
*/
used = unpack_object_header_gently(buf, avail,
&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) {
unsigned char c;
const unsigned char *base_name;
off_t 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
* base object to deltify other objects
* against, in order to avoid circular deltas.
*/
/* uncompressed size of the delta data */
entry->size = size;
entry->delta = base_entry;
entry->type = entry->in_pack_type;
entry->delta_sibling = base_entry->delta_child;
base_entry->delta_child = entry;
return;
}
/* Otherwise we would do the usual */
}
entry->type = sha1_object_info(entry->sha1, &entry->size);
if (entry->type < 0)
die("unable to get type of object %s",
sha1_to_hex(entry->sha1));
}
static unsigned int check_delta_limit(struct object_entry *me, unsigned int n)
{
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)
{
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);
}
static struct object_entry **create_sorted_list(entry_sort_t sort)
{
struct object_entry **list = xmalloc(nr_objects * sizeof(struct object_entry *));
uint32_t i;
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;
}
static int sha1_sort(const struct object_entry *a, const struct object_entry *b)
{
return hashcmp(a->sha1, b->sha1);
}
static struct object_entry **create_final_object_list(void)
{
struct object_entry **list;
uint32_t i, j;
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;
}
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)
{
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);
}
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,
unsigned max_depth)
{
struct object_entry *trg_entry = trg->entry;
struct object_entry *src_entry = src->entry;
unsigned long trg_size, src_size, delta_size, sizediff, max_size, sz;
enum object_type type;
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;
/*
* We do not bother to try a delta that we discarded
* 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_type != OBJ_REF_DELTA &&
trg_entry->in_pack_type != OBJ_OFS_DELTA)
return 0;
/*
* 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. */
trg_size = trg_entry->size;
max_size = trg_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 < trg_size ? trg_size - src_size : 0;
if (sizediff >= max_size)
return 0;
/* Load data if not already done */
if (!trg->data) {
trg->data = read_sha1_file(trg_entry->sha1, &type, &sz);
if (sz != trg_size)
die("object %s inconsistent object length (%lu vs %lu)",
sha1_to_hex(trg_entry->sha1), sz, trg_size);
}
if (!src->data) {
src->data = read_sha1_file(src_entry->sha1, &type, &sz);
if (sz != src_size)
die("object %s inconsistent object length (%lu vs %lu)",
sha1_to_hex(src_entry->sha1), sz, src_size);
}
if (!src->index) {
src->index = create_delta_index(src->data, src_size);
if (!src->index)
die("out of memory");
}
delta_buf = create_delta(src->index, trg->data, trg_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)
{
uint32_t i = nr_objects, idx = 0, processed = 0;
unsigned int array_size = window * sizeof(struct unpacked);
struct unpacked *array;
unsigned last_percent = 999;
if (!nr_objects)
return;
array = xmalloc(array_size);
memset(array, 0, array_size);
if (progress)
fprintf(stderr, "Deltifying %u objects.\n", nr_result);
do {
struct object_entry *entry = list[--i];
struct unpacked *n = array + idx;
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->data = NULL;
n->entry = entry;
j = window;
while (--j > 0) {
uint32_t 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, 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;
idx++;
if (idx >= window)
idx = 0;
} while (i > 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)
{
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 %u 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));
}
return 1;
}
static void setup_progress_signal(void)
{
struct sigaction sa;
struct itimerval v;
memset(&sa, 0, sizeof(sa));
sa.sa_handler = progress_interval;
sigemptyset(&sa.sa_mask);
sa.sa_flags = SA_RESTART;
sigaction(SIGALRM, &sa, NULL);
v.it_interval.tv_sec = 1;
v.it_interval.tv_usec = 0;
v.it_value = v.it_interval;
setitimer(ITIMER_REAL, &v, NULL);
}
static int git_pack_config(const char *k, const char *v)
{
if(!strcmp(k, "pack.window")) {
window = git_config_int(k, v);
return 0;
}
return git_default_config(k, v);
}
static void read_object_list_from_stdin(void)
{
char line[40 + 1 + PATH_MAX + 2];
unsigned char sha1[20];
unsigned hash;
for (;;) {
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;
}
if (line[0] == '-') {
if (get_sha1_hex(line+1, sha1))
die("expected edge sha1, got garbage:\n %s",
line);
add_preferred_base(sha1);
continue;
}
if (get_sha1_hex(line, sha1))
die("expected sha1, got garbage:\n %s", line);
hash = name_hash(line+41);
add_preferred_base_object(line+41, hash);
add_object_entry(sha1, hash, 0);
}
}
static void show_commit(struct commit *commit)
{
unsigned hash = name_hash("");
add_preferred_base_object("", hash);
add_object_entry(commit->object.sha1, hash, 0);
}
static void show_object(struct object_array_entry *p)
{
unsigned hash = name_hash(p->name);
add_preferred_base_object(p->name, hash);
add_object_entry(p->item->sha1, hash, 0);
}
static void show_edge(struct commit *commit)
{
add_preferred_base(commit->object.sha1);
}
static void get_object_list(int ac, const char **av)
{
struct rev_info revs;
char line[1000];
int flags = 0;
init_revisions(&revs, NULL);
save_commit_buffer = 0;
track_object_refs = 0;
setup_revisions(ac, av, &revs, NULL);
while (fgets(line, sizeof(line), stdin) != NULL) {
int len = strlen(line);
if (line[len - 1] == '\n')
line[--len] = 0;
if (!len)
break;
if (*line == '-') {
if (!strcmp(line, "--not")) {
flags ^= UNINTERESTING;
continue;
}
die("not a rev '%s'", line);
}
if (handle_revision_arg(line, &revs, flags, 1))
die("bad revision '%s'", line);
}
prepare_revision_walk(&revs);
mark_edges_uninteresting(revs.commits, &revs, show_edge);
traverse_commit_list(&revs, show_commit, show_object);
}
int cmd_pack_objects(int argc, const char **argv, const char *prefix)
{
SHA_CTX ctx;
int depth = 10;
struct object_entry **list;
int use_internal_rev_list = 0;
int thin = 0;
uint32_t i;
const char **rp_av;
int rp_ac_alloc = 64;
int rp_ac;
rp_av = xcalloc(rp_ac_alloc, sizeof(*rp_av));
rp_av[0] = "pack-objects";
rp_av[1] = "--objects"; /* --thin will make it --objects-edge */
rp_ac = 2;
git_config(git_pack_config);
progress = isatty(2);
for (i = 1; i < argc; i++) {
const char *arg = argv[i];
if (*arg != '-')
break;
if (!strcmp("--non-empty", arg)) {
non_empty = 1;
continue;
}
if (!strcmp("--local", arg)) {
local = 1;
continue;
}
if (!strcmp("--incremental", arg)) {
incremental = 1;
continue;
}
if (!prefixcmp(arg, "--window=")) {
char *end;
window = strtoul(arg+9, &end, 0);
if (!arg[9] || *end)
usage(pack_usage);
continue;
}
if (!prefixcmp(arg, "--depth=")) {
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("--all-progress", arg)) {
progress = 2;
continue;
}
if (!strcmp("-q", arg)) {
progress = 0;
continue;
}
if (!strcmp("--no-reuse-delta", arg)) {
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;
}
if (!strcmp("--revs", arg)) {
use_internal_rev_list = 1;
continue;
}
if (!strcmp("--unpacked", arg) ||
!prefixcmp(arg, "--unpacked=") ||
!strcmp("--reflog", arg) ||
!strcmp("--all", arg)) {
use_internal_rev_list = 1;
if (rp_ac >= rp_ac_alloc - 1) {
rp_ac_alloc = alloc_nr(rp_ac_alloc);
rp_av = xrealloc(rp_av,
rp_ac_alloc * sizeof(*rp_av));
}
rp_av[rp_ac++] = arg;
continue;
}
if (!strcmp("--thin", arg)) {
use_internal_rev_list = 1;
thin = 1;
rp_av[1] = "--objects-edge";
continue;
}
usage(pack_usage);
}
/* Traditionally "pack-objects [options] base extra" failed;
* we would however want to take refs parameter that would
* have been given to upstream rev-list ourselves, which means
* we somehow want to say what the base name is. So the
* syntax would be:
*
* pack-objects [options] base <refs...>
*
* in other words, we would treat the first non-option as the
* base_name and send everything else to the internal revision
* walker.
*/
if (!pack_to_stdout)
base_name = argv[i++];
if (pack_to_stdout != !base_name)
usage(pack_usage);
if (!pack_to_stdout && thin)
die("--thin cannot be used to build an indexable pack.");
prepare_packed_git();
if (progress) {
fprintf(stderr, "Generating pack...\n");
setup_progress_signal();
}
if (!use_internal_rev_list)
read_object_list_from_stdin();
else {
rp_av[rp_ac] = NULL;
get_object_list(rp_ac, rp_av);
}
if (progress)
fprintf(stderr, "Done counting %u objects.\n", nr_objects);
sorted_by_sha = create_final_object_list();
if (non_empty && !nr_result)
return 0;
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 %u objects.\n", nr_result);
if (reuse_cached_pack(object_list_sha1))
;
else {
if (nr_result)
prepare_pack(window, depth);
if (progress == 1 && 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 %u (delta %u), reused %u (delta %u)\n",
written, written_delta, reused, reused_delta);
return 0;
}