#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 */
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) */
#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;
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 int 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 {
unsigned int 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 int written;
static int written_delta;
static int reused;
static int 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;
void *index = p->index_base + 256;
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].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,
unsigned int 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 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;
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)
{
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,
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];
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 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;
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.
*/
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);
free(buf);
}
else {
struct packed_git *p = entry->in_pack;
struct pack_window *w_curs = NULL;
unsigned long 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;
}
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 unsigned long write_one(struct sha1file *f,
struct object_entry *e,
unsigned long 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)
{
int i;
struct sha1file *f;
unsigned long 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 %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:
if (written != nr_result)
die("wrote %d objects while expecting %d", written, nr_result);
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 (!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)
{
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;
}
}
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)
{
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) {
unsigned long 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) {
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));
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...%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 && !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 (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;
}
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;
char type[20];
if (entry.pathlen != cmplen ||
memcmp(entry.path, name, cmplen) ||
!has_sha1_file(entry.sha1) ||
sha1_object_info(entry.sha1, type, &size))
continue;
if (name[cmplen] != '/') {
unsigned hash = name_hash(fullname);
add_object_entry(entry.sha1, hash, 1);
return;
}
if (!strcmp(type, tree_type)) {
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;
sub.buf = tree->tree_data;
sub.size = 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;
tree.buf = it->pcache.tree_data;
tree.size = 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)
{
char type[20];
if (entry->in_pack && !entry->preferred_base) {
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.
*/
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) {
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
* 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 */
}
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);
}
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)
{
int 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 *));
int 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;
int 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;
char type[10];
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)
{
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;
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) {
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, 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;
}
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 %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));
}
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;
int i;
const char *rp_av[64];
int rp_ac;
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 (!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("--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) ||
!strncmp("--unpacked=", arg, 11) ||
!strcmp("--reflog", arg) ||
!strcmp("--all", arg)) {
use_internal_rev_list = 1;
if (ARRAY_SIZE(rp_av) - 1 <= rp_ac)
die("too many internal rev-list options");
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 %d 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 %d 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 %d (delta %d), reused %d (delta %d)\n",
written, written_delta, reused, reused_delta);
return 0;
}