Skip to content
This repository

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
tag: v1.5.3.2
Fetching contributors…

Cannot retrieve contributors at this time

file 404 lines (359 sloc) 8.854 kb
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404
#include "builtin.h"
#include "cache.h"
#include "object.h"
#include "delta.h"
#include "pack.h"
#include "blob.h"
#include "commit.h"
#include "tag.h"
#include "tree.h"
#include "progress.h"

static int dry_run, quiet, recover, has_errors;
static const char unpack_usage[] = "git-unpack-objects [-n] [-q] [-r] < pack-file";

/* We always read in 4kB chunks. */
static unsigned char buffer[4096];
static unsigned int offset, len;
static off_t consumed_bytes;
static SHA_CTX ctx;

/*
* 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) {
SHA1_Update(&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("read error on input: %s", strerror(errno));
}
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 (consumed_bytes > consumed_bytes + bytes)
die("pack too large for current definition of off_t");
consumed_bytes += bytes;
}

static void *get_data(unsigned long size)
{
z_stream stream;
void *buf = xmalloc(size);

memset(&stream, 0, sizeof(stream));

stream.next_out = buf;
stream.avail_out = size;
stream.next_in = fill(1);
stream.avail_in = len;
inflateInit(&stream);

for (;;) {
int ret = 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\n", ret);
free(buf);
buf = NULL;
if (!recover)
exit(1);
has_errors = 1;
break;
}
stream.next_in = fill(1);
stream.avail_in = len;
}
inflateEnd(&stream);
return buf;
}

struct delta_info {
unsigned char base_sha1[20];
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, unsigned const char *base_sha1,
off_t base_offset,
void *delta, unsigned long size)
{
struct delta_info *info = xmalloc(sizeof(*info));

hashcpy(info->base_sha1, base_sha1);
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;
unsigned char sha1[20];
};

static struct obj_info *obj_list;

static void added_object(unsigned nr, enum object_type type,
void *data, unsigned long size);

static void write_object(unsigned nr, enum object_type type,
void *buf, unsigned long size)
{
if (write_sha1_file(buf, size, typename(type), obj_list[nr].sha1) < 0)
die("failed to write object");
added_object(nr, type, buf, size);
}

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);
free(result);
}

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 (!hashcmp(info->base_sha1, obj_list[nr].sha1) ||
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);
free(buf);
}

static void unpack_delta_entry(enum object_type type, unsigned long delta_size,
unsigned nr)
{
void *delta_data, *base;
unsigned long base_size;
unsigned char base_sha1[20];

if (type == OBJ_REF_DELTA) {
hashcpy(base_sha1, fill(20));
use(20);
delta_data = get_data(delta_size);
if (dry_run || !delta_data) {
free(delta_data);
return;
}
if (!has_sha1_file(base_sha1)) {
hashcpy(obj_list[nr].sha1, null_sha1);
add_delta_to_list(nr, base_sha1, 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;

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)/2;
if (base_offset < obj_list[mid].offset) {
hi = mid;
} else if (base_offset > obj_list[mid].offset) {
lo = mid + 1;
} else {
hashcpy(base_sha1, obj_list[mid].sha1);
base_found = !is_null_sha1(base_sha1);
break;
}
}
if (!base_found) {
/* The delta base object is itself a delta that
has not been resolved yet. */
hashcpy(obj_list[nr].sha1, null_sha1);
add_delta_to_list(nr, null_sha1, base_offset, delta_data, delta_size);
return;
}
}

base = read_sha1_file(base_sha1, &type, &base_size);
if (!base) {
error("failed to read delta-pack base object %s",
sha1_to_hex(base_sha1));
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, c;
unsigned long size;
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;
struct pack_header *hdr = fill(sizeof(struct pack_header));
unsigned 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 %d", ntohl(hdr->hdr_version));
use(sizeof(struct pack_header));

if (!quiet)
start_progress(&progress, "Unpacking %u objects...", "", nr_objects);
obj_list = xmalloc(nr_objects * sizeof(*obj_list));
for (i = 0; i < nr_objects; i++) {
unpack_one(i);
if (!quiet)
display_progress(&progress, i + 1);
}
if (!quiet)
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;
unsigned char sha1[20];

git_config(git_default_config);

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 (!prefixcmp(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;
}
usage(unpack_usage);
}

/* We don't take any non-flag arguments now.. Maybe some day */
usage(unpack_usage);
}
SHA1_Init(&ctx);
unpack_all();
SHA1_Update(&ctx, buffer, offset);
SHA1_Final(sha1, &ctx);
if (hashcmp(fill(20), sha1))
die("final sha1 did not match");
use(20);

/* 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;
}
Something went wrong with that request. Please try again.