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index-pack.c
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#include "builtin.h"
#include "delta.h"
#include "pack.h"
#include "csum-file.h"
#include "blob.h"
#include "commit.h"
#include "tag.h"
#include "tree.h"
#include "progress.h"
#include "fsck.h"
#include "exec_cmd.h"
#include "streaming.h"
#include "thread-utils.h"
static const char index_pack_usage[] =
"git index-pack [-v] [-o <index-file>] [--keep | --keep=<msg>] [--verify] [--strict] (<pack-file> | --stdin [--fix-thin] [<pack-file>])";
struct object_entry {
struct pack_idx_entry idx;
unsigned long size;
unsigned int hdr_size;
enum object_type type;
enum object_type real_type;
unsigned delta_depth;
int base_object_no;
};
union delta_base {
unsigned char sha1[20];
off_t offset;
};
struct base_data {
struct base_data *base;
struct base_data *child;
struct object_entry *obj;
void *data;
unsigned long size;
int ref_first, ref_last;
int ofs_first, ofs_last;
};
#if !defined(NO_PTHREADS) && defined(NO_THREAD_SAFE_PREAD)
/* pread() emulation is not thread-safe. Disable threading. */
#define NO_PTHREADS
#endif
struct thread_local {
#ifndef NO_PTHREADS
pthread_t thread;
#endif
struct base_data *base_cache;
size_t base_cache_used;
};
/*
* Even if sizeof(union delta_base) == 24 on 64-bit archs, we really want
* to memcmp() only the first 20 bytes.
*/
#define UNION_BASE_SZ 20
#define FLAG_LINK (1u<<20)
#define FLAG_CHECKED (1u<<21)
struct delta_entry {
union delta_base base;
int obj_no;
};
static struct object_entry *objects;
static struct delta_entry *deltas;
static struct thread_local nothread_data;
static int nr_objects;
static int nr_deltas;
static int nr_resolved_deltas;
static int nr_threads;
static int from_stdin;
static int strict;
static int verbose;
static struct progress *progress;
/* We always read in 4kB chunks. */
static unsigned char input_buffer[4096];
static unsigned int input_offset, input_len;
static off_t consumed_bytes;
static unsigned deepest_delta;
static git_SHA_CTX input_ctx;
static uint32_t input_crc32;
static int input_fd, output_fd, pack_fd;
#ifndef NO_PTHREADS
static struct thread_local *thread_data;
static int nr_dispatched;
static int threads_active;
static pthread_mutex_t read_mutex;
#define read_lock() lock_mutex(&read_mutex)
#define read_unlock() unlock_mutex(&read_mutex)
static pthread_mutex_t counter_mutex;
#define counter_lock() lock_mutex(&counter_mutex)
#define counter_unlock() unlock_mutex(&counter_mutex)
static pthread_mutex_t work_mutex;
#define work_lock() lock_mutex(&work_mutex)
#define work_unlock() unlock_mutex(&work_mutex)
static pthread_key_t key;
static inline void lock_mutex(pthread_mutex_t *mutex)
{
if (threads_active)
pthread_mutex_lock(mutex);
}
static inline void unlock_mutex(pthread_mutex_t *mutex)
{
if (threads_active)
pthread_mutex_unlock(mutex);
}
/*
* Mutex and conditional variable can't be statically-initialized on Windows.
*/
static void init_thread(void)
{
init_recursive_mutex(&read_mutex);
pthread_mutex_init(&counter_mutex, NULL);
pthread_mutex_init(&work_mutex, NULL);
pthread_key_create(&key, NULL);
thread_data = xcalloc(nr_threads, sizeof(*thread_data));
threads_active = 1;
}
static void cleanup_thread(void)
{
if (!threads_active)
return;
threads_active = 0;
pthread_mutex_destroy(&read_mutex);
pthread_mutex_destroy(&counter_mutex);
pthread_mutex_destroy(&work_mutex);
pthread_key_delete(key);
free(thread_data);
}
#else
#define read_lock()
#define read_unlock()
#define counter_lock()
#define counter_unlock()
#define work_lock()
#define work_unlock()
#endif
static int mark_link(struct object *obj, int type, void *data)
{
if (!obj)
return -1;
if (type != OBJ_ANY && obj->type != type)
die(_("object type mismatch at %s"), sha1_to_hex(obj->sha1));
obj->flags |= FLAG_LINK;
return 0;
}
/* The content of each linked object must have been checked
or it must be already present in the object database */
static void check_object(struct object *obj)
{
if (!obj)
return;
if (!(obj->flags & FLAG_LINK))
return;
if (!(obj->flags & FLAG_CHECKED)) {
unsigned long size;
int type = sha1_object_info(obj->sha1, &size);
if (type != obj->type || type <= 0)
die(_("object of unexpected type"));
obj->flags |= FLAG_CHECKED;
return;
}
}
static void check_objects(void)
{
unsigned i, max;
max = get_max_object_index();
for (i = 0; i < max; i++)
check_object(get_indexed_object(i));
}
/* Discard current buffer used content. */
static void flush(void)
{
if (input_offset) {
if (output_fd >= 0)
write_or_die(output_fd, input_buffer, input_offset);
git_SHA1_Update(&input_ctx, input_buffer, input_offset);
memmove(input_buffer, input_buffer + input_offset, input_len);
input_offset = 0;
}
}
/*
* Make sure at least "min" bytes are available in the buffer, and
* return the pointer to the buffer.
*/
static void *fill(int min)
{
if (min <= input_len)
return input_buffer + input_offset;
if (min > sizeof(input_buffer))
die(Q_("cannot fill %d byte",
"cannot fill %d bytes",
min),
min);
flush();
do {
ssize_t ret = xread(input_fd, input_buffer + input_len,
sizeof(input_buffer) - input_len);
if (ret <= 0) {
if (!ret)
die(_("early EOF"));
die_errno(_("read error on input"));
}
input_len += ret;
if (from_stdin)
display_throughput(progress, consumed_bytes + input_len);
} while (input_len < min);
return input_buffer;
}
static void use(int bytes)
{
if (bytes > input_len)
die(_("used more bytes than were available"));
input_crc32 = crc32(input_crc32, input_buffer + input_offset, bytes);
input_len -= bytes;
input_offset += bytes;
/* make sure off_t is sufficiently large not to wrap */
if (signed_add_overflows(consumed_bytes, bytes))
die(_("pack too large for current definition of off_t"));
consumed_bytes += bytes;
}
static const char *open_pack_file(const char *pack_name)
{
if (from_stdin) {
input_fd = 0;
if (!pack_name) {
static char tmp_file[PATH_MAX];
output_fd = odb_mkstemp(tmp_file, sizeof(tmp_file),
"pack/tmp_pack_XXXXXX");
pack_name = xstrdup(tmp_file);
} else
output_fd = open(pack_name, O_CREAT|O_EXCL|O_RDWR, 0600);
if (output_fd < 0)
die_errno(_("unable to create '%s'"), pack_name);
pack_fd = output_fd;
} else {
input_fd = open(pack_name, O_RDONLY);
if (input_fd < 0)
die_errno(_("cannot open packfile '%s'"), pack_name);
output_fd = -1;
pack_fd = input_fd;
}
git_SHA1_Init(&input_ctx);
return pack_name;
}
static void parse_pack_header(void)
{
struct pack_header *hdr = fill(sizeof(struct pack_header));
/* Header consistency check */
if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
die(_("pack signature mismatch"));
if (!pack_version_ok(hdr->hdr_version))
die(_("pack version %"PRIu32" unsupported"),
ntohl(hdr->hdr_version));
nr_objects = ntohl(hdr->hdr_entries);
use(sizeof(struct pack_header));
}
static NORETURN void bad_object(unsigned long offset, const char *format,
...) __attribute__((format (printf, 2, 3)));
static NORETURN void bad_object(unsigned long offset, const char *format, ...)
{
va_list params;
char buf[1024];
va_start(params, format);
vsnprintf(buf, sizeof(buf), format, params);
va_end(params);
die(_("pack has bad object at offset %lu: %s"), offset, buf);
}
static inline struct thread_local *get_thread_data(void)
{
#ifndef NO_PTHREADS
if (threads_active)
return pthread_getspecific(key);
assert(!threads_active &&
"This should only be reached when all threads are gone");
#endif
return ¬hread_data;
}
#ifndef NO_PTHREADS
static void set_thread_data(struct thread_local *data)
{
if (threads_active)
pthread_setspecific(key, data);
}
#endif
static struct base_data *alloc_base_data(void)
{
struct base_data *base = xmalloc(sizeof(struct base_data));
memset(base, 0, sizeof(*base));
base->ref_last = -1;
base->ofs_last = -1;
return base;
}
static void free_base_data(struct base_data *c)
{
if (c->data) {
free(c->data);
c->data = NULL;
get_thread_data()->base_cache_used -= c->size;
}
}
static void prune_base_data(struct base_data *retain)
{
struct base_data *b;
struct thread_local *data = get_thread_data();
for (b = data->base_cache;
data->base_cache_used > delta_base_cache_limit && b;
b = b->child) {
if (b->data && b != retain)
free_base_data(b);
}
}
static void link_base_data(struct base_data *base, struct base_data *c)
{
if (base)
base->child = c;
else
get_thread_data()->base_cache = c;
c->base = base;
c->child = NULL;
if (c->data)
get_thread_data()->base_cache_used += c->size;
prune_base_data(c);
}
static void unlink_base_data(struct base_data *c)
{
struct base_data *base = c->base;
if (base)
base->child = NULL;
else
get_thread_data()->base_cache = NULL;
free_base_data(c);
}
static int is_delta_type(enum object_type type)
{
return (type == OBJ_REF_DELTA || type == OBJ_OFS_DELTA);
}
static void *unpack_entry_data(unsigned long offset, unsigned long size,
enum object_type type, unsigned char *sha1)
{
static char fixed_buf[8192];
int status;
git_zstream stream;
void *buf;
git_SHA_CTX c;
char hdr[32];
int hdrlen;
if (!is_delta_type(type)) {
hdrlen = sprintf(hdr, "%s %lu", typename(type), size) + 1;
git_SHA1_Init(&c);
git_SHA1_Update(&c, hdr, hdrlen);
} else
sha1 = NULL;
if (type == OBJ_BLOB && size > big_file_threshold)
buf = fixed_buf;
else
buf = xmalloc(size);
memset(&stream, 0, sizeof(stream));
git_inflate_init(&stream);
stream.next_out = buf;
stream.avail_out = buf == fixed_buf ? sizeof(fixed_buf) : size;
do {
unsigned char *last_out = stream.next_out;
stream.next_in = fill(1);
stream.avail_in = input_len;
status = git_inflate(&stream, 0);
use(input_len - stream.avail_in);
if (sha1)
git_SHA1_Update(&c, last_out, stream.next_out - last_out);
if (buf == fixed_buf) {
stream.next_out = buf;
stream.avail_out = sizeof(fixed_buf);
}
} while (status == Z_OK);
if (stream.total_out != size || status != Z_STREAM_END)
bad_object(offset, _("inflate returned %d"), status);
git_inflate_end(&stream);
if (sha1)
git_SHA1_Final(sha1, &c);
return buf == fixed_buf ? NULL : buf;
}
static void *unpack_raw_entry(struct object_entry *obj,
union delta_base *delta_base,
unsigned char *sha1)
{
unsigned char *p;
unsigned long size, c;
off_t base_offset;
unsigned shift;
void *data;
obj->idx.offset = consumed_bytes;
input_crc32 = crc32(0, NULL, 0);
p = fill(1);
c = *p;
use(1);
obj->type = (c >> 4) & 7;
size = (c & 15);
shift = 4;
while (c & 0x80) {
p = fill(1);
c = *p;
use(1);
size += (c & 0x7f) << shift;
shift += 7;
}
obj->size = size;
switch (obj->type) {
case OBJ_REF_DELTA:
hashcpy(delta_base->sha1, fill(20));
use(20);
break;
case OBJ_OFS_DELTA:
memset(delta_base, 0, sizeof(*delta_base));
p = fill(1);
c = *p;
use(1);
base_offset = c & 127;
while (c & 128) {
base_offset += 1;
if (!base_offset || MSB(base_offset, 7))
bad_object(obj->idx.offset, _("offset value overflow for delta base object"));
p = fill(1);
c = *p;
use(1);
base_offset = (base_offset << 7) + (c & 127);
}
delta_base->offset = obj->idx.offset - base_offset;
if (delta_base->offset <= 0 || delta_base->offset >= obj->idx.offset)
bad_object(obj->idx.offset, _("delta base offset is out of bound"));
break;
case OBJ_COMMIT:
case OBJ_TREE:
case OBJ_BLOB:
case OBJ_TAG:
break;
default:
bad_object(obj->idx.offset, _("unknown object type %d"), obj->type);
}
obj->hdr_size = consumed_bytes - obj->idx.offset;
data = unpack_entry_data(obj->idx.offset, obj->size, obj->type, sha1);
obj->idx.crc32 = input_crc32;
return data;
}
static void *unpack_data(struct object_entry *obj,
int (*consume)(const unsigned char *, unsigned long, void *),
void *cb_data)
{
off_t from = obj[0].idx.offset + obj[0].hdr_size;
unsigned long len = obj[1].idx.offset - from;
unsigned char *data, *inbuf;
git_zstream stream;
int status;
data = xmalloc(consume ? 64*1024 : obj->size);
inbuf = xmalloc((len < 64*1024) ? len : 64*1024);
memset(&stream, 0, sizeof(stream));
git_inflate_init(&stream);
stream.next_out = data;
stream.avail_out = consume ? 64*1024 : obj->size;
do {
ssize_t n = (len < 64*1024) ? len : 64*1024;
n = pread(pack_fd, inbuf, n, from);
if (n < 0)
die_errno(_("cannot pread pack file"));
if (!n)
die(Q_("premature end of pack file, %lu byte missing",
"premature end of pack file, %lu bytes missing",
len),
len);
from += n;
len -= n;
stream.next_in = inbuf;
stream.avail_in = n;
if (!consume)
status = git_inflate(&stream, 0);
else {
do {
status = git_inflate(&stream, 0);
if (consume(data, stream.next_out - data, cb_data)) {
free(inbuf);
free(data);
return NULL;
}
stream.next_out = data;
stream.avail_out = 64*1024;
} while (status == Z_OK && stream.avail_in);
}
} while (len && status == Z_OK && !stream.avail_in);
/* This has been inflated OK when first encountered, so... */
if (status != Z_STREAM_END || stream.total_out != obj->size)
die(_("serious inflate inconsistency"));
git_inflate_end(&stream);
free(inbuf);
if (consume) {
free(data);
data = NULL;
}
return data;
}
static void *get_data_from_pack(struct object_entry *obj)
{
return unpack_data(obj, NULL, NULL);
}
static int compare_delta_bases(const union delta_base *base1,
const union delta_base *base2,
enum object_type type1,
enum object_type type2)
{
int cmp = type1 - type2;
if (cmp)
return cmp;
return memcmp(base1, base2, UNION_BASE_SZ);
}
static int find_delta(const union delta_base *base, enum object_type type)
{
int first = 0, last = nr_deltas;
while (first < last) {
int next = (first + last) / 2;
struct delta_entry *delta = &deltas[next];
int cmp;
cmp = compare_delta_bases(base, &delta->base,
type, objects[delta->obj_no].type);
if (!cmp)
return next;
if (cmp < 0) {
last = next;
continue;
}
first = next+1;
}
return -first-1;
}
static void find_delta_children(const union delta_base *base,
int *first_index, int *last_index,
enum object_type type)
{
int first = find_delta(base, type);
int last = first;
int end = nr_deltas - 1;
if (first < 0) {
*first_index = 0;
*last_index = -1;
return;
}
while (first > 0 && !memcmp(&deltas[first - 1].base, base, UNION_BASE_SZ))
--first;
while (last < end && !memcmp(&deltas[last + 1].base, base, UNION_BASE_SZ))
++last;
*first_index = first;
*last_index = last;
}
struct compare_data {
struct object_entry *entry;
struct git_istream *st;
unsigned char *buf;
unsigned long buf_size;
};
static int compare_objects(const unsigned char *buf, unsigned long size,
void *cb_data)
{
struct compare_data *data = cb_data;
if (data->buf_size < size) {
free(data->buf);
data->buf = xmalloc(size);
data->buf_size = size;
}
while (size) {
ssize_t len = read_istream(data->st, data->buf, size);
if (len == 0)
die(_("SHA1 COLLISION FOUND WITH %s !"),
sha1_to_hex(data->entry->idx.sha1));
if (len < 0)
die(_("unable to read %s"),
sha1_to_hex(data->entry->idx.sha1));
if (memcmp(buf, data->buf, len))
die(_("SHA1 COLLISION FOUND WITH %s !"),
sha1_to_hex(data->entry->idx.sha1));
size -= len;
buf += len;
}
return 0;
}
static int check_collison(struct object_entry *entry)
{
struct compare_data data;
enum object_type type;
unsigned long size;
if (entry->size <= big_file_threshold || entry->type != OBJ_BLOB)
return -1;
memset(&data, 0, sizeof(data));
data.entry = entry;
data.st = open_istream(entry->idx.sha1, &type, &size, NULL);
if (!data.st)
return -1;
if (size != entry->size || type != entry->type)
die(_("SHA1 COLLISION FOUND WITH %s !"),
sha1_to_hex(entry->idx.sha1));
unpack_data(entry, compare_objects, &data);
close_istream(data.st);
free(data.buf);
return 0;
}
static void sha1_object(const void *data, struct object_entry *obj_entry,
unsigned long size, enum object_type type,
const unsigned char *sha1)
{
void *new_data = NULL;
int collision_test_needed;
assert(data || obj_entry);
read_lock();
collision_test_needed = has_sha1_file(sha1);
read_unlock();
if (collision_test_needed && !data) {
read_lock();
if (!check_collison(obj_entry))
collision_test_needed = 0;
read_unlock();
}
if (collision_test_needed) {
void *has_data;
enum object_type has_type;
unsigned long has_size;
read_lock();
has_type = sha1_object_info(sha1, &has_size);
if (has_type != type || has_size != size)
die(_("SHA1 COLLISION FOUND WITH %s !"), sha1_to_hex(sha1));
has_data = read_sha1_file(sha1, &has_type, &has_size);
read_unlock();
if (!data)
data = new_data = get_data_from_pack(obj_entry);
if (!has_data)
die(_("cannot read existing object %s"), sha1_to_hex(sha1));
if (size != has_size || type != has_type ||
memcmp(data, has_data, size) != 0)
die(_("SHA1 COLLISION FOUND WITH %s !"), sha1_to_hex(sha1));
free(has_data);
}
if (strict) {
read_lock();
if (type == OBJ_BLOB) {
struct blob *blob = lookup_blob(sha1);
if (blob)
blob->object.flags |= FLAG_CHECKED;
else
die(_("invalid blob object %s"), sha1_to_hex(sha1));
} else {
struct object *obj;
int eaten;
void *buf = (void *) data;
if (!buf)
buf = new_data = get_data_from_pack(obj_entry);
/*
* we do not need to free the memory here, as the
* buf is deleted by the caller.
*/
obj = parse_object_buffer(sha1, type, size, buf, &eaten);
if (!obj)
die(_("invalid %s"), typename(type));
if (fsck_object(obj, 1, fsck_error_function))
die(_("Error in object"));
if (fsck_walk(obj, mark_link, NULL))
die(_("Not all child objects of %s are reachable"), sha1_to_hex(obj->sha1));
if (obj->type == OBJ_TREE) {
struct tree *item = (struct tree *) obj;
item->buffer = NULL;
}
if (obj->type == OBJ_COMMIT) {
struct commit *commit = (struct commit *) obj;
commit->buffer = NULL;
}
obj->flags |= FLAG_CHECKED;
}
read_unlock();
}
free(new_data);
}
/*
* This function is part of find_unresolved_deltas(). There are two
* walkers going in the opposite ways.
*
* The first one in find_unresolved_deltas() traverses down from
* parent node to children, deflating nodes along the way. However,
* memory for deflated nodes is limited by delta_base_cache_limit, so
* at some point parent node's deflated content may be freed.
*
* The second walker is this function, which goes from current node up
* to top parent if necessary to deflate the node. In normal
* situation, its parent node would be already deflated, so it just
* needs to apply delta.
*
* In the worst case scenario, parent node is no longer deflated because
* we're running out of delta_base_cache_limit; we need to re-deflate
* parents, possibly up to the top base.
*
* All deflated objects here are subject to be freed if we exceed
* delta_base_cache_limit, just like in find_unresolved_deltas(), we
* just need to make sure the last node is not freed.
*/
static void *get_base_data(struct base_data *c)
{
if (!c->data) {
struct object_entry *obj = c->obj;
struct base_data **delta = NULL;
int delta_nr = 0, delta_alloc = 0;
while (is_delta_type(c->obj->type) && !c->data) {
ALLOC_GROW(delta, delta_nr + 1, delta_alloc);
delta[delta_nr++] = c;
c = c->base;
}
if (!delta_nr) {
c->data = get_data_from_pack(obj);
c->size = obj->size;
get_thread_data()->base_cache_used += c->size;
prune_base_data(c);
}
for (; delta_nr > 0; delta_nr--) {
void *base, *raw;
c = delta[delta_nr - 1];
obj = c->obj;
base = get_base_data(c->base);
raw = get_data_from_pack(obj);
c->data = patch_delta(
base, c->base->size,
raw, obj->size,
&c->size);
free(raw);
if (!c->data)
bad_object(obj->idx.offset, _("failed to apply delta"));
get_thread_data()->base_cache_used += c->size;
prune_base_data(c);
}
free(delta);
}
return c->data;
}
static void resolve_delta(struct object_entry *delta_obj,
struct base_data *base, struct base_data *result)
{
void *base_data, *delta_data;
delta_obj->real_type = base->obj->real_type;
delta_obj->delta_depth = base->obj->delta_depth + 1;
if (deepest_delta < delta_obj->delta_depth)
deepest_delta = delta_obj->delta_depth;
delta_obj->base_object_no = base->obj - objects;
delta_data = get_data_from_pack(delta_obj);
base_data = get_base_data(base);
result->obj = delta_obj;
result->data = patch_delta(base_data, base->size,
delta_data, delta_obj->size, &result->size);
free(delta_data);
if (!result->data)
bad_object(delta_obj->idx.offset, _("failed to apply delta"));
hash_sha1_file(result->data, result->size,
typename(delta_obj->real_type), delta_obj->idx.sha1);
sha1_object(result->data, NULL, result->size, delta_obj->real_type,
delta_obj->idx.sha1);
counter_lock();
nr_resolved_deltas++;
counter_unlock();
}
static struct base_data *find_unresolved_deltas_1(struct base_data *base,
struct base_data *prev_base)
{
if (base->ref_last == -1 && base->ofs_last == -1) {
union delta_base base_spec;
hashcpy(base_spec.sha1, base->obj->idx.sha1);
find_delta_children(&base_spec,
&base->ref_first, &base->ref_last, OBJ_REF_DELTA);
memset(&base_spec, 0, sizeof(base_spec));
base_spec.offset = base->obj->idx.offset;
find_delta_children(&base_spec,
&base->ofs_first, &base->ofs_last, OBJ_OFS_DELTA);
if (base->ref_last == -1 && base->ofs_last == -1) {
free(base->data);
return NULL;
}
link_base_data(prev_base, base);
}
if (base->ref_first <= base->ref_last) {
struct object_entry *child = objects + deltas[base->ref_first].obj_no;
struct base_data *result = alloc_base_data();
assert(child->real_type == OBJ_REF_DELTA);
resolve_delta(child, base, result);
if (base->ref_first == base->ref_last && base->ofs_last == -1)
free_base_data(base);
base->ref_first++;
return result;
}
if (base->ofs_first <= base->ofs_last) {
struct object_entry *child = objects + deltas[base->ofs_first].obj_no;
struct base_data *result = alloc_base_data();
assert(child->real_type == OBJ_OFS_DELTA);
resolve_delta(child, base, result);
if (base->ofs_first == base->ofs_last)
free_base_data(base);
base->ofs_first++;
return result;
}
unlink_base_data(base);
return NULL;
}
static void find_unresolved_deltas(struct base_data *base)
{
struct base_data *new_base, *prev_base = NULL;
for (;;) {
new_base = find_unresolved_deltas_1(base, prev_base);
if (new_base) {
prev_base = base;
base = new_base;
} else {
free(base);
base = prev_base;
if (!base)
return;
prev_base = base->base;
}
}
}
static int compare_delta_entry(const void *a, const void *b)
{
const struct delta_entry *delta_a = a;
const struct delta_entry *delta_b = b;
/* group by type (ref vs ofs) and then by value (sha-1 or offset) */
return compare_delta_bases(&delta_a->base, &delta_b->base,
objects[delta_a->obj_no].type,
objects[delta_b->obj_no].type);
}
static void resolve_base(struct object_entry *obj)
{
struct base_data *base_obj = alloc_base_data();
base_obj->obj = obj;
base_obj->data = NULL;
find_unresolved_deltas(base_obj);
}
#ifndef NO_PTHREADS
static void *threaded_second_pass(void *data)
{
set_thread_data(data);
for (;;) {
int i;
work_lock();
display_progress(progress, nr_resolved_deltas);
while (nr_dispatched < nr_objects &&
is_delta_type(objects[nr_dispatched].type))
nr_dispatched++;
if (nr_dispatched >= nr_objects) {
work_unlock();
break;
}
i = nr_dispatched++;
work_unlock();
resolve_base(&objects[i]);
}
return NULL;
}
#endif
/*
* First pass:
* - find locations of all objects;
* - calculate SHA1 of all non-delta objects;
* - remember base (SHA1 or offset) for all deltas.
*/
static void parse_pack_objects(unsigned char *sha1)
{
int i, nr_delays = 0;
struct delta_entry *delta = deltas;
struct stat st;
if (verbose)
progress = start_progress(
from_stdin ? _("Receiving objects") : _("Indexing objects"),
nr_objects);
for (i = 0; i < nr_objects; i++) {
struct object_entry *obj = &objects[i];
void *data = unpack_raw_entry(obj, &delta->base, obj->idx.sha1);
obj->real_type = obj->type;
if (is_delta_type(obj->type)) {
nr_deltas++;
delta->obj_no = i;
delta++;
} else if (!data) {
/* large blobs, check later */
obj->real_type = OBJ_BAD;
nr_delays++;
} else