mirror of
https://github.com/git/git
synced 2024-08-27 19:49:21 +00:00
![brian m. carlson](/assets/img/avatar_default.png)
Switch various uses of explicit calls to SHA-1 into references to the_hash_algo to better abstract away the various uses of it. Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
589 lines
14 KiB
C
589 lines
14 KiB
C
#include "builtin.h"
|
|
#include "cache.h"
|
|
#include "config.h"
|
|
#include "object.h"
|
|
#include "delta.h"
|
|
#include "pack.h"
|
|
#include "blob.h"
|
|
#include "commit.h"
|
|
#include "tag.h"
|
|
#include "tree.h"
|
|
#include "tree-walk.h"
|
|
#include "progress.h"
|
|
#include "decorate.h"
|
|
#include "fsck.h"
|
|
|
|
static int dry_run, quiet, recover, has_errors, strict;
|
|
static const char unpack_usage[] = "git unpack-objects [-n] [-q] [-r] [--strict]";
|
|
|
|
/* We always read in 4kB chunks. */
|
|
static unsigned char buffer[4096];
|
|
static unsigned int offset, len;
|
|
static off_t consumed_bytes;
|
|
static off_t max_input_size;
|
|
static git_hash_ctx ctx;
|
|
static struct fsck_options fsck_options = FSCK_OPTIONS_STRICT;
|
|
|
|
/*
|
|
* When running under --strict mode, objects whose reachability are
|
|
* suspect are kept in core without getting written in the object
|
|
* store.
|
|
*/
|
|
struct obj_buffer {
|
|
char *buffer;
|
|
unsigned long size;
|
|
};
|
|
|
|
static struct decoration obj_decorate;
|
|
|
|
static struct obj_buffer *lookup_object_buffer(struct object *base)
|
|
{
|
|
return lookup_decoration(&obj_decorate, base);
|
|
}
|
|
|
|
static void add_object_buffer(struct object *object, char *buffer, unsigned long size)
|
|
{
|
|
struct obj_buffer *obj;
|
|
obj = xcalloc(1, sizeof(struct obj_buffer));
|
|
obj->buffer = buffer;
|
|
obj->size = size;
|
|
if (add_decoration(&obj_decorate, object, obj))
|
|
die("object %s tried to add buffer twice!", oid_to_hex(&object->oid));
|
|
}
|
|
|
|
/*
|
|
* 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 <= len)
|
|
return buffer + offset;
|
|
if (min > sizeof(buffer))
|
|
die("cannot fill %d bytes", min);
|
|
if (offset) {
|
|
the_hash_algo->update_fn(&ctx, buffer, offset);
|
|
memmove(buffer, buffer + offset, len);
|
|
offset = 0;
|
|
}
|
|
do {
|
|
ssize_t ret = xread(0, buffer + len, sizeof(buffer) - len);
|
|
if (ret <= 0) {
|
|
if (!ret)
|
|
die("early EOF");
|
|
die_errno("read error on input");
|
|
}
|
|
len += ret;
|
|
} while (len < min);
|
|
return buffer;
|
|
}
|
|
|
|
static void use(int bytes)
|
|
{
|
|
if (bytes > len)
|
|
die("used more bytes than were available");
|
|
len -= bytes;
|
|
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;
|
|
if (max_input_size && consumed_bytes > max_input_size)
|
|
die(_("pack exceeds maximum allowed size"));
|
|
}
|
|
|
|
static void *get_data(unsigned long size)
|
|
{
|
|
git_zstream stream;
|
|
void *buf = xmallocz(size);
|
|
|
|
memset(&stream, 0, sizeof(stream));
|
|
|
|
stream.next_out = buf;
|
|
stream.avail_out = size;
|
|
stream.next_in = fill(1);
|
|
stream.avail_in = len;
|
|
git_inflate_init(&stream);
|
|
|
|
for (;;) {
|
|
int ret = git_inflate(&stream, 0);
|
|
use(len - stream.avail_in);
|
|
if (stream.total_out == size && ret == Z_STREAM_END)
|
|
break;
|
|
if (ret != Z_OK) {
|
|
error("inflate returned %d", ret);
|
|
FREE_AND_NULL(buf);
|
|
if (!recover)
|
|
exit(1);
|
|
has_errors = 1;
|
|
break;
|
|
}
|
|
stream.next_in = fill(1);
|
|
stream.avail_in = len;
|
|
}
|
|
git_inflate_end(&stream);
|
|
return buf;
|
|
}
|
|
|
|
struct delta_info {
|
|
struct object_id base_oid;
|
|
unsigned nr;
|
|
off_t base_offset;
|
|
unsigned long size;
|
|
void *delta;
|
|
struct delta_info *next;
|
|
};
|
|
|
|
static struct delta_info *delta_list;
|
|
|
|
static void add_delta_to_list(unsigned nr, const struct object_id *base_oid,
|
|
off_t base_offset,
|
|
void *delta, unsigned long size)
|
|
{
|
|
struct delta_info *info = xmalloc(sizeof(*info));
|
|
|
|
oidcpy(&info->base_oid, base_oid);
|
|
info->base_offset = base_offset;
|
|
info->size = size;
|
|
info->delta = delta;
|
|
info->nr = nr;
|
|
info->next = delta_list;
|
|
delta_list = info;
|
|
}
|
|
|
|
struct obj_info {
|
|
off_t offset;
|
|
struct object_id oid;
|
|
struct object *obj;
|
|
};
|
|
|
|
#define FLAG_OPEN (1u<<20)
|
|
#define FLAG_WRITTEN (1u<<21)
|
|
|
|
static struct obj_info *obj_list;
|
|
static unsigned nr_objects;
|
|
|
|
/*
|
|
* Called only from check_object() after it verified this object
|
|
* is Ok.
|
|
*/
|
|
static void write_cached_object(struct object *obj, struct obj_buffer *obj_buf)
|
|
{
|
|
struct object_id oid;
|
|
|
|
if (write_sha1_file(obj_buf->buffer, obj_buf->size, typename(obj->type), oid.hash) < 0)
|
|
die("failed to write object %s", oid_to_hex(&obj->oid));
|
|
obj->flags |= FLAG_WRITTEN;
|
|
}
|
|
|
|
/*
|
|
* At the very end of the processing, write_rest() scans the objects
|
|
* that have reachability requirements and calls this function.
|
|
* Verify its reachability and validity recursively and write it out.
|
|
*/
|
|
static int check_object(struct object *obj, int type, void *data, struct fsck_options *options)
|
|
{
|
|
struct obj_buffer *obj_buf;
|
|
|
|
if (!obj)
|
|
return 1;
|
|
|
|
if (obj->flags & FLAG_WRITTEN)
|
|
return 0;
|
|
|
|
if (type != OBJ_ANY && obj->type != type)
|
|
die("object type mismatch");
|
|
|
|
if (!(obj->flags & FLAG_OPEN)) {
|
|
unsigned long size;
|
|
int type = sha1_object_info(obj->oid.hash, &size);
|
|
if (type != obj->type || type <= 0)
|
|
die("object of unexpected type");
|
|
obj->flags |= FLAG_WRITTEN;
|
|
return 0;
|
|
}
|
|
|
|
obj_buf = lookup_object_buffer(obj);
|
|
if (!obj_buf)
|
|
die("Whoops! Cannot find object '%s'", oid_to_hex(&obj->oid));
|
|
if (fsck_object(obj, obj_buf->buffer, obj_buf->size, &fsck_options))
|
|
die("Error in object");
|
|
fsck_options.walk = check_object;
|
|
if (fsck_walk(obj, NULL, &fsck_options))
|
|
die("Error on reachable objects of %s", oid_to_hex(&obj->oid));
|
|
write_cached_object(obj, obj_buf);
|
|
return 0;
|
|
}
|
|
|
|
static void write_rest(void)
|
|
{
|
|
unsigned i;
|
|
for (i = 0; i < nr_objects; i++) {
|
|
if (obj_list[i].obj)
|
|
check_object(obj_list[i].obj, OBJ_ANY, NULL, NULL);
|
|
}
|
|
}
|
|
|
|
static void added_object(unsigned nr, enum object_type type,
|
|
void *data, unsigned long size);
|
|
|
|
/*
|
|
* Write out nr-th object from the list, now we know the contents
|
|
* of it. Under --strict, this buffers structured objects in-core,
|
|
* to be checked at the end.
|
|
*/
|
|
static void write_object(unsigned nr, enum object_type type,
|
|
void *buf, unsigned long size)
|
|
{
|
|
if (!strict) {
|
|
if (write_sha1_file(buf, size, typename(type), obj_list[nr].oid.hash) < 0)
|
|
die("failed to write object");
|
|
added_object(nr, type, buf, size);
|
|
free(buf);
|
|
obj_list[nr].obj = NULL;
|
|
} else if (type == OBJ_BLOB) {
|
|
struct blob *blob;
|
|
if (write_sha1_file(buf, size, typename(type), obj_list[nr].oid.hash) < 0)
|
|
die("failed to write object");
|
|
added_object(nr, type, buf, size);
|
|
free(buf);
|
|
|
|
blob = lookup_blob(&obj_list[nr].oid);
|
|
if (blob)
|
|
blob->object.flags |= FLAG_WRITTEN;
|
|
else
|
|
die("invalid blob object");
|
|
obj_list[nr].obj = NULL;
|
|
} else {
|
|
struct object *obj;
|
|
int eaten;
|
|
hash_sha1_file(buf, size, typename(type), obj_list[nr].oid.hash);
|
|
added_object(nr, type, buf, size);
|
|
obj = parse_object_buffer(&obj_list[nr].oid, type, size, buf,
|
|
&eaten);
|
|
if (!obj)
|
|
die("invalid %s", typename(type));
|
|
add_object_buffer(obj, buf, size);
|
|
obj->flags |= FLAG_OPEN;
|
|
obj_list[nr].obj = obj;
|
|
}
|
|
}
|
|
|
|
static void resolve_delta(unsigned nr, enum object_type type,
|
|
void *base, unsigned long base_size,
|
|
void *delta, unsigned long delta_size)
|
|
{
|
|
void *result;
|
|
unsigned long result_size;
|
|
|
|
result = patch_delta(base, base_size,
|
|
delta, delta_size,
|
|
&result_size);
|
|
if (!result)
|
|
die("failed to apply delta");
|
|
free(delta);
|
|
write_object(nr, type, result, result_size);
|
|
}
|
|
|
|
/*
|
|
* We now know the contents of an object (which is nr-th in the pack);
|
|
* resolve all the deltified objects that are based on it.
|
|
*/
|
|
static void added_object(unsigned nr, enum object_type type,
|
|
void *data, unsigned long size)
|
|
{
|
|
struct delta_info **p = &delta_list;
|
|
struct delta_info *info;
|
|
|
|
while ((info = *p) != NULL) {
|
|
if (!oidcmp(&info->base_oid, &obj_list[nr].oid) ||
|
|
info->base_offset == obj_list[nr].offset) {
|
|
*p = info->next;
|
|
p = &delta_list;
|
|
resolve_delta(info->nr, type, data, size,
|
|
info->delta, info->size);
|
|
free(info);
|
|
continue;
|
|
}
|
|
p = &info->next;
|
|
}
|
|
}
|
|
|
|
static void unpack_non_delta_entry(enum object_type type, unsigned long size,
|
|
unsigned nr)
|
|
{
|
|
void *buf = get_data(size);
|
|
|
|
if (!dry_run && buf)
|
|
write_object(nr, type, buf, size);
|
|
else
|
|
free(buf);
|
|
}
|
|
|
|
static int resolve_against_held(unsigned nr, const struct object_id *base,
|
|
void *delta_data, unsigned long delta_size)
|
|
{
|
|
struct object *obj;
|
|
struct obj_buffer *obj_buffer;
|
|
obj = lookup_object(base->hash);
|
|
if (!obj)
|
|
return 0;
|
|
obj_buffer = lookup_object_buffer(obj);
|
|
if (!obj_buffer)
|
|
return 0;
|
|
resolve_delta(nr, obj->type, obj_buffer->buffer,
|
|
obj_buffer->size, delta_data, delta_size);
|
|
return 1;
|
|
}
|
|
|
|
static void unpack_delta_entry(enum object_type type, unsigned long delta_size,
|
|
unsigned nr)
|
|
{
|
|
void *delta_data, *base;
|
|
unsigned long base_size;
|
|
struct object_id base_oid;
|
|
|
|
if (type == OBJ_REF_DELTA) {
|
|
hashcpy(base_oid.hash, fill(the_hash_algo->rawsz));
|
|
use(the_hash_algo->rawsz);
|
|
delta_data = get_data(delta_size);
|
|
if (dry_run || !delta_data) {
|
|
free(delta_data);
|
|
return;
|
|
}
|
|
if (has_object_file(&base_oid))
|
|
; /* Ok we have this one */
|
|
else if (resolve_against_held(nr, &base_oid,
|
|
delta_data, delta_size))
|
|
return; /* we are done */
|
|
else {
|
|
/* cannot resolve yet --- queue it */
|
|
oidclr(&obj_list[nr].oid);
|
|
add_delta_to_list(nr, &base_oid, 0, delta_data, delta_size);
|
|
return;
|
|
}
|
|
} else {
|
|
unsigned base_found = 0;
|
|
unsigned char *pack, c;
|
|
off_t base_offset;
|
|
unsigned lo, mid, hi;
|
|
|
|
pack = fill(1);
|
|
c = *pack;
|
|
use(1);
|
|
base_offset = c & 127;
|
|
while (c & 128) {
|
|
base_offset += 1;
|
|
if (!base_offset || MSB(base_offset, 7))
|
|
die("offset value overflow for delta base object");
|
|
pack = fill(1);
|
|
c = *pack;
|
|
use(1);
|
|
base_offset = (base_offset << 7) + (c & 127);
|
|
}
|
|
base_offset = obj_list[nr].offset - base_offset;
|
|
if (base_offset <= 0 || base_offset >= obj_list[nr].offset)
|
|
die("offset value out of bound for delta base object");
|
|
|
|
delta_data = get_data(delta_size);
|
|
if (dry_run || !delta_data) {
|
|
free(delta_data);
|
|
return;
|
|
}
|
|
lo = 0;
|
|
hi = nr;
|
|
while (lo < hi) {
|
|
mid = lo + (hi - lo) / 2;
|
|
if (base_offset < obj_list[mid].offset) {
|
|
hi = mid;
|
|
} else if (base_offset > obj_list[mid].offset) {
|
|
lo = mid + 1;
|
|
} else {
|
|
oidcpy(&base_oid, &obj_list[mid].oid);
|
|
base_found = !is_null_oid(&base_oid);
|
|
break;
|
|
}
|
|
}
|
|
if (!base_found) {
|
|
/*
|
|
* The delta base object is itself a delta that
|
|
* has not been resolved yet.
|
|
*/
|
|
oidclr(&obj_list[nr].oid);
|
|
add_delta_to_list(nr, &null_oid, base_offset, delta_data, delta_size);
|
|
return;
|
|
}
|
|
}
|
|
|
|
if (resolve_against_held(nr, &base_oid, delta_data, delta_size))
|
|
return;
|
|
|
|
base = read_sha1_file(base_oid.hash, &type, &base_size);
|
|
if (!base) {
|
|
error("failed to read delta-pack base object %s",
|
|
oid_to_hex(&base_oid));
|
|
if (!recover)
|
|
exit(1);
|
|
has_errors = 1;
|
|
return;
|
|
}
|
|
resolve_delta(nr, type, base, base_size, delta_data, delta_size);
|
|
free(base);
|
|
}
|
|
|
|
static void unpack_one(unsigned nr)
|
|
{
|
|
unsigned shift;
|
|
unsigned char *pack;
|
|
unsigned long size, c;
|
|
enum object_type type;
|
|
|
|
obj_list[nr].offset = consumed_bytes;
|
|
|
|
pack = fill(1);
|
|
c = *pack;
|
|
use(1);
|
|
type = (c >> 4) & 7;
|
|
size = (c & 15);
|
|
shift = 4;
|
|
while (c & 0x80) {
|
|
pack = fill(1);
|
|
c = *pack;
|
|
use(1);
|
|
size += (c & 0x7f) << shift;
|
|
shift += 7;
|
|
}
|
|
|
|
switch (type) {
|
|
case OBJ_COMMIT:
|
|
case OBJ_TREE:
|
|
case OBJ_BLOB:
|
|
case OBJ_TAG:
|
|
unpack_non_delta_entry(type, size, nr);
|
|
return;
|
|
case OBJ_REF_DELTA:
|
|
case OBJ_OFS_DELTA:
|
|
unpack_delta_entry(type, size, nr);
|
|
return;
|
|
default:
|
|
error("bad object type %d", type);
|
|
has_errors = 1;
|
|
if (recover)
|
|
return;
|
|
exit(1);
|
|
}
|
|
}
|
|
|
|
static void unpack_all(void)
|
|
{
|
|
int i;
|
|
struct progress *progress = NULL;
|
|
struct pack_header *hdr = fill(sizeof(struct pack_header));
|
|
|
|
nr_objects = ntohl(hdr->hdr_entries);
|
|
|
|
if (ntohl(hdr->hdr_signature) != PACK_SIGNATURE)
|
|
die("bad pack file");
|
|
if (!pack_version_ok(hdr->hdr_version))
|
|
die("unknown pack file version %"PRIu32,
|
|
ntohl(hdr->hdr_version));
|
|
use(sizeof(struct pack_header));
|
|
|
|
if (!quiet)
|
|
progress = start_progress(_("Unpacking objects"), nr_objects);
|
|
obj_list = xcalloc(nr_objects, sizeof(*obj_list));
|
|
for (i = 0; i < nr_objects; i++) {
|
|
unpack_one(i);
|
|
display_progress(progress, i + 1);
|
|
}
|
|
stop_progress(&progress);
|
|
|
|
if (delta_list)
|
|
die("unresolved deltas left after unpacking");
|
|
}
|
|
|
|
int cmd_unpack_objects(int argc, const char **argv, const char *prefix)
|
|
{
|
|
int i;
|
|
struct object_id oid;
|
|
|
|
check_replace_refs = 0;
|
|
|
|
git_config(git_default_config, NULL);
|
|
|
|
quiet = !isatty(2);
|
|
|
|
for (i = 1 ; i < argc; i++) {
|
|
const char *arg = argv[i];
|
|
|
|
if (*arg == '-') {
|
|
if (!strcmp(arg, "-n")) {
|
|
dry_run = 1;
|
|
continue;
|
|
}
|
|
if (!strcmp(arg, "-q")) {
|
|
quiet = 1;
|
|
continue;
|
|
}
|
|
if (!strcmp(arg, "-r")) {
|
|
recover = 1;
|
|
continue;
|
|
}
|
|
if (!strcmp(arg, "--strict")) {
|
|
strict = 1;
|
|
continue;
|
|
}
|
|
if (skip_prefix(arg, "--strict=", &arg)) {
|
|
strict = 1;
|
|
fsck_set_msg_types(&fsck_options, arg);
|
|
continue;
|
|
}
|
|
if (starts_with(arg, "--pack_header=")) {
|
|
struct pack_header *hdr;
|
|
char *c;
|
|
|
|
hdr = (struct pack_header *)buffer;
|
|
hdr->hdr_signature = htonl(PACK_SIGNATURE);
|
|
hdr->hdr_version = htonl(strtoul(arg + 14, &c, 10));
|
|
if (*c != ',')
|
|
die("bad %s", arg);
|
|
hdr->hdr_entries = htonl(strtoul(c + 1, &c, 10));
|
|
if (*c)
|
|
die("bad %s", arg);
|
|
len = sizeof(*hdr);
|
|
continue;
|
|
}
|
|
if (skip_prefix(arg, "--max-input-size=", &arg)) {
|
|
max_input_size = strtoumax(arg, NULL, 10);
|
|
continue;
|
|
}
|
|
usage(unpack_usage);
|
|
}
|
|
|
|
/* We don't take any non-flag arguments now.. Maybe some day */
|
|
usage(unpack_usage);
|
|
}
|
|
the_hash_algo->init_fn(&ctx);
|
|
unpack_all();
|
|
the_hash_algo->update_fn(&ctx, buffer, offset);
|
|
the_hash_algo->final_fn(oid.hash, &ctx);
|
|
if (strict)
|
|
write_rest();
|
|
if (hashcmp(fill(the_hash_algo->rawsz), oid.hash))
|
|
die("final sha1 did not match");
|
|
use(the_hash_algo->rawsz);
|
|
|
|
/* Write the last part of the buffer to stdout */
|
|
while (len) {
|
|
int ret = xwrite(1, buffer + offset, len);
|
|
if (ret <= 0)
|
|
break;
|
|
len -= ret;
|
|
offset += ret;
|
|
}
|
|
|
|
/* All done */
|
|
return has_errors;
|
|
}
|