/
sha1_file.c
1874 lines (1648 loc) · 41.8 KB
/
sha1_file.c
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/*
* GIT - The information manager from hell
*
* Copyright (C) Linus Torvalds, 2005
*
* This handles basic git sha1 object files - packing, unpacking,
* creation etc.
*/
#include "cache.h"
#include "delta.h"
#include "pack.h"
#include "blob.h"
#include "commit.h"
#include "tag.h"
#include "tree.h"
#ifndef O_NOATIME
#if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
#define O_NOATIME 01000000
#else
#define O_NOATIME 0
#endif
#endif
const unsigned char null_sha1[20] = { 0, };
static unsigned int sha1_file_open_flag = O_NOATIME;
static unsigned hexval(char c)
{
if (c >= '0' && c <= '9')
return c - '0';
if (c >= 'a' && c <= 'f')
return c - 'a' + 10;
if (c >= 'A' && c <= 'F')
return c - 'A' + 10;
return ~0;
}
int get_sha1_hex(const char *hex, unsigned char *sha1)
{
int i;
for (i = 0; i < 20; i++) {
unsigned int val = (hexval(hex[0]) << 4) | hexval(hex[1]);
if (val & ~0xff)
return -1;
*sha1++ = val;
hex += 2;
}
return 0;
}
int safe_create_leading_directories(char *path)
{
char *pos = path;
struct stat st;
if (*pos == '/')
pos++;
while (pos) {
pos = strchr(pos, '/');
if (!pos)
break;
*pos = 0;
if (!stat(path, &st)) {
/* path exists */
if (!S_ISDIR(st.st_mode)) {
*pos = '/';
return -3;
}
}
else if (mkdir(path, 0777)) {
*pos = '/';
return -1;
}
else if (adjust_shared_perm(path)) {
*pos = '/';
return -2;
}
*pos++ = '/';
}
return 0;
}
char * sha1_to_hex(const unsigned char *sha1)
{
static int bufno;
static char hexbuffer[4][50];
static const char hex[] = "0123456789abcdef";
char *buffer = hexbuffer[3 & ++bufno], *buf = buffer;
int i;
for (i = 0; i < 20; i++) {
unsigned int val = *sha1++;
*buf++ = hex[val >> 4];
*buf++ = hex[val & 0xf];
}
*buf = '\0';
return buffer;
}
static void fill_sha1_path(char *pathbuf, const unsigned char *sha1)
{
int i;
for (i = 0; i < 20; i++) {
static char hex[] = "0123456789abcdef";
unsigned int val = sha1[i];
char *pos = pathbuf + i*2 + (i > 0);
*pos++ = hex[val >> 4];
*pos = hex[val & 0xf];
}
}
/*
* NOTE! This returns a statically allocated buffer, so you have to be
* careful about using it. Do a "strdup()" if you need to save the
* filename.
*
* Also note that this returns the location for creating. Reading
* SHA1 file can happen from any alternate directory listed in the
* DB_ENVIRONMENT environment variable if it is not found in
* the primary object database.
*/
char *sha1_file_name(const unsigned char *sha1)
{
static char *name, *base;
if (!base) {
const char *sha1_file_directory = get_object_directory();
int len = strlen(sha1_file_directory);
base = xmalloc(len + 60);
memcpy(base, sha1_file_directory, len);
memset(base+len, 0, 60);
base[len] = '/';
base[len+3] = '/';
name = base + len + 1;
}
fill_sha1_path(name, sha1);
return base;
}
char *sha1_pack_name(const unsigned char *sha1)
{
static const char hex[] = "0123456789abcdef";
static char *name, *base, *buf;
int i;
if (!base) {
const char *sha1_file_directory = get_object_directory();
int len = strlen(sha1_file_directory);
base = xmalloc(len + 60);
sprintf(base, "%s/pack/pack-1234567890123456789012345678901234567890.pack", sha1_file_directory);
name = base + len + 11;
}
buf = name;
for (i = 0; i < 20; i++) {
unsigned int val = *sha1++;
*buf++ = hex[val >> 4];
*buf++ = hex[val & 0xf];
}
return base;
}
char *sha1_pack_index_name(const unsigned char *sha1)
{
static const char hex[] = "0123456789abcdef";
static char *name, *base, *buf;
int i;
if (!base) {
const char *sha1_file_directory = get_object_directory();
int len = strlen(sha1_file_directory);
base = xmalloc(len + 60);
sprintf(base, "%s/pack/pack-1234567890123456789012345678901234567890.idx", sha1_file_directory);
name = base + len + 11;
}
buf = name;
for (i = 0; i < 20; i++) {
unsigned int val = *sha1++;
*buf++ = hex[val >> 4];
*buf++ = hex[val & 0xf];
}
return base;
}
struct alternate_object_database *alt_odb_list;
static struct alternate_object_database **alt_odb_tail;
static void read_info_alternates(const char * alternates, int depth);
/*
* Prepare alternate object database registry.
*
* The variable alt_odb_list points at the list of struct
* alternate_object_database. The elements on this list come from
* non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
* environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
* whose contents is similar to that environment variable but can be
* LF separated. Its base points at a statically allocated buffer that
* contains "/the/directory/corresponding/to/.git/objects/...", while
* its name points just after the slash at the end of ".git/objects/"
* in the example above, and has enough space to hold 40-byte hex
* SHA1, an extra slash for the first level indirection, and the
* terminating NUL.
*/
static int link_alt_odb_entry(const char * entry, int len, const char * relative_base, int depth)
{
struct stat st;
const char *objdir = get_object_directory();
struct alternate_object_database *ent;
struct alternate_object_database *alt;
/* 43 = 40-byte + 2 '/' + terminating NUL */
int pfxlen = len;
int entlen = pfxlen + 43;
int base_len = -1;
if (*entry != '/' && relative_base) {
/* Relative alt-odb */
if (base_len < 0)
base_len = strlen(relative_base) + 1;
entlen += base_len;
pfxlen += base_len;
}
ent = xmalloc(sizeof(*ent) + entlen);
if (*entry != '/' && relative_base) {
memcpy(ent->base, relative_base, base_len - 1);
ent->base[base_len - 1] = '/';
memcpy(ent->base + base_len, entry, len);
}
else
memcpy(ent->base, entry, pfxlen);
ent->name = ent->base + pfxlen + 1;
ent->base[pfxlen + 3] = '/';
ent->base[pfxlen] = ent->base[entlen-1] = 0;
/* Detect cases where alternate disappeared */
if (stat(ent->base, &st) || !S_ISDIR(st.st_mode)) {
error("object directory %s does not exist; "
"check .git/objects/info/alternates.",
ent->base);
free(ent);
return -1;
}
/* Prevent the common mistake of listing the same
* thing twice, or object directory itself.
*/
for (alt = alt_odb_list; alt; alt = alt->next) {
if (!memcmp(ent->base, alt->base, pfxlen)) {
free(ent);
return -1;
}
}
if (!memcmp(ent->base, objdir, pfxlen)) {
free(ent);
return -1;
}
/* add the alternate entry */
*alt_odb_tail = ent;
alt_odb_tail = &(ent->next);
ent->next = NULL;
/* recursively add alternates */
read_info_alternates(ent->base, depth + 1);
ent->base[pfxlen] = '/';
return 0;
}
static void link_alt_odb_entries(const char *alt, const char *ep, int sep,
const char *relative_base, int depth)
{
const char *cp, *last;
if (depth > 5) {
error("%s: ignoring alternate object stores, nesting too deep.",
relative_base);
return;
}
last = alt;
while (last < ep) {
cp = last;
if (cp < ep && *cp == '#') {
while (cp < ep && *cp != sep)
cp++;
last = cp + 1;
continue;
}
while (cp < ep && *cp != sep)
cp++;
if (last != cp) {
if ((*last != '/') && depth) {
error("%s: ignoring relative alternate object store %s",
relative_base, last);
} else {
link_alt_odb_entry(last, cp - last,
relative_base, depth);
}
}
while (cp < ep && *cp == sep)
cp++;
last = cp;
}
}
static void read_info_alternates(const char * relative_base, int depth)
{
char *map;
struct stat st;
char path[PATH_MAX];
int fd;
sprintf(path, "%s/info/alternates", relative_base);
fd = open(path, O_RDONLY);
if (fd < 0)
return;
if (fstat(fd, &st) || (st.st_size == 0)) {
close(fd);
return;
}
map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
close(fd);
if (map == MAP_FAILED)
return;
link_alt_odb_entries(map, map + st.st_size, '\n', relative_base, depth);
munmap(map, st.st_size);
}
void prepare_alt_odb(void)
{
const char *alt;
alt = getenv(ALTERNATE_DB_ENVIRONMENT);
if (!alt) alt = "";
if (alt_odb_tail)
return;
alt_odb_tail = &alt_odb_list;
link_alt_odb_entries(alt, alt + strlen(alt), ':', NULL, 0);
read_info_alternates(get_object_directory(), 0);
}
static char *find_sha1_file(const unsigned char *sha1, struct stat *st)
{
char *name = sha1_file_name(sha1);
struct alternate_object_database *alt;
if (!stat(name, st))
return name;
prepare_alt_odb();
for (alt = alt_odb_list; alt; alt = alt->next) {
name = alt->name;
fill_sha1_path(name, sha1);
if (!stat(alt->base, st))
return alt->base;
}
return NULL;
}
#define PACK_MAX_SZ (1<<26)
static int pack_used_ctr;
static unsigned long pack_mapped;
struct packed_git *packed_git;
static int check_packed_git_idx(const char *path, unsigned long *idx_size_,
void **idx_map_)
{
void *idx_map;
unsigned int *index;
unsigned long idx_size;
int nr, i;
int fd = open(path, O_RDONLY);
struct stat st;
if (fd < 0)
return -1;
if (fstat(fd, &st)) {
close(fd);
return -1;
}
idx_size = st.st_size;
idx_map = mmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0);
close(fd);
if (idx_map == MAP_FAILED)
return -1;
index = idx_map;
*idx_map_ = idx_map;
*idx_size_ = idx_size;
/* check index map */
if (idx_size < 4*256 + 20 + 20)
return error("index file too small");
nr = 0;
for (i = 0; i < 256; i++) {
unsigned int n = ntohl(index[i]);
if (n < nr)
return error("non-monotonic index");
nr = n;
}
/*
* Total size:
* - 256 index entries 4 bytes each
* - 24-byte entries * nr (20-byte sha1 + 4-byte offset)
* - 20-byte SHA1 of the packfile
* - 20-byte SHA1 file checksum
*/
if (idx_size != 4*256 + nr * 24 + 20 + 20)
return error("wrong index file size");
return 0;
}
static int unuse_one_packed_git(void)
{
struct packed_git *p, *lru = NULL;
for (p = packed_git; p; p = p->next) {
if (p->pack_use_cnt || !p->pack_base)
continue;
if (!lru || p->pack_last_used < lru->pack_last_used)
lru = p;
}
if (!lru)
return 0;
munmap(lru->pack_base, lru->pack_size);
lru->pack_base = NULL;
return 1;
}
void unuse_packed_git(struct packed_git *p)
{
p->pack_use_cnt--;
}
int use_packed_git(struct packed_git *p)
{
if (!p->pack_size) {
struct stat st;
/* We created the struct before we had the pack */
stat(p->pack_name, &st);
if (!S_ISREG(st.st_mode))
die("packfile %s not a regular file", p->pack_name);
p->pack_size = st.st_size;
}
if (!p->pack_base) {
int fd;
struct stat st;
void *map;
pack_mapped += p->pack_size;
while (PACK_MAX_SZ < pack_mapped && unuse_one_packed_git())
; /* nothing */
fd = open(p->pack_name, O_RDONLY);
if (fd < 0)
die("packfile %s cannot be opened", p->pack_name);
if (fstat(fd, &st)) {
close(fd);
die("packfile %s cannot be opened", p->pack_name);
}
if (st.st_size != p->pack_size)
die("packfile %s size mismatch.", p->pack_name);
map = mmap(NULL, p->pack_size, PROT_READ, MAP_PRIVATE, fd, 0);
close(fd);
if (map == MAP_FAILED)
die("packfile %s cannot be mapped.", p->pack_name);
p->pack_base = map;
/* Check if the pack file matches with the index file.
* this is cheap.
*/
if (memcmp((char*)(p->index_base) + p->index_size - 40,
(char *) p->pack_base + p->pack_size - 20,
20)) {
die("packfile %s does not match index.", p->pack_name);
}
}
p->pack_last_used = pack_used_ctr++;
p->pack_use_cnt++;
return 0;
}
struct packed_git *add_packed_git(char *path, int path_len, int local)
{
struct stat st;
struct packed_git *p;
unsigned long idx_size;
void *idx_map;
unsigned char sha1[20];
if (check_packed_git_idx(path, &idx_size, &idx_map))
return NULL;
/* do we have a corresponding .pack file? */
strcpy(path + path_len - 4, ".pack");
if (stat(path, &st) || !S_ISREG(st.st_mode)) {
munmap(idx_map, idx_size);
return NULL;
}
/* ok, it looks sane as far as we can check without
* actually mapping the pack file.
*/
p = xmalloc(sizeof(*p) + path_len + 2);
strcpy(p->pack_name, path);
p->index_size = idx_size;
p->pack_size = st.st_size;
p->index_base = idx_map;
p->next = NULL;
p->pack_base = NULL;
p->pack_last_used = 0;
p->pack_use_cnt = 0;
p->pack_local = local;
if ((path_len > 44) && !get_sha1_hex(path + path_len - 44, sha1))
memcpy(p->sha1, sha1, 20);
return p;
}
struct packed_git *parse_pack_index(unsigned char *sha1)
{
char *path = sha1_pack_index_name(sha1);
return parse_pack_index_file(sha1, path);
}
struct packed_git *parse_pack_index_file(const unsigned char *sha1, char *idx_path)
{
struct packed_git *p;
unsigned long idx_size;
void *idx_map;
char *path;
if (check_packed_git_idx(idx_path, &idx_size, &idx_map))
return NULL;
path = sha1_pack_name(sha1);
p = xmalloc(sizeof(*p) + strlen(path) + 2);
strcpy(p->pack_name, path);
p->index_size = idx_size;
p->pack_size = 0;
p->index_base = idx_map;
p->next = NULL;
p->pack_base = NULL;
p->pack_last_used = 0;
p->pack_use_cnt = 0;
memcpy(p->sha1, sha1, 20);
return p;
}
void install_packed_git(struct packed_git *pack)
{
pack->next = packed_git;
packed_git = pack;
}
static void prepare_packed_git_one(char *objdir, int local)
{
char path[PATH_MAX];
int len;
DIR *dir;
struct dirent *de;
sprintf(path, "%s/pack", objdir);
len = strlen(path);
dir = opendir(path);
if (!dir) {
if (errno != ENOENT)
error("unable to open object pack directory: %s: %s",
path, strerror(errno));
return;
}
path[len++] = '/';
while ((de = readdir(dir)) != NULL) {
int namelen = strlen(de->d_name);
struct packed_git *p;
if (strcmp(de->d_name + namelen - 4, ".idx"))
continue;
/* we have .idx. Is it a file we can map? */
strcpy(path + len, de->d_name);
for (p = packed_git; p; p = p->next) {
if (!memcmp(path, p->pack_name, len + namelen - 4))
break;
}
if (p)
continue;
p = add_packed_git(path, len + namelen, local);
if (!p)
continue;
p->next = packed_git;
packed_git = p;
}
closedir(dir);
}
static int prepare_packed_git_run_once = 0;
void prepare_packed_git(void)
{
struct alternate_object_database *alt;
if (prepare_packed_git_run_once)
return;
prepare_packed_git_one(get_object_directory(), 1);
prepare_alt_odb();
for (alt = alt_odb_list; alt; alt = alt->next) {
alt->name[-1] = 0;
prepare_packed_git_one(alt->base, 0);
alt->name[-1] = '/';
}
prepare_packed_git_run_once = 1;
}
static void reprepare_packed_git(void)
{
prepare_packed_git_run_once = 0;
prepare_packed_git();
}
int check_sha1_signature(const unsigned char *sha1, void *map, unsigned long size, const char *type)
{
char header[100];
unsigned char real_sha1[20];
SHA_CTX c;
SHA1_Init(&c);
SHA1_Update(&c, header, 1+sprintf(header, "%s %lu", type, size));
SHA1_Update(&c, map, size);
SHA1_Final(real_sha1, &c);
return memcmp(sha1, real_sha1, 20) ? -1 : 0;
}
static void *map_sha1_file_internal(const unsigned char *sha1,
unsigned long *size)
{
struct stat st;
void *map;
int fd;
char *filename = find_sha1_file(sha1, &st);
if (!filename) {
return NULL;
}
fd = open(filename, O_RDONLY | sha1_file_open_flag);
if (fd < 0) {
/* See if it works without O_NOATIME */
switch (sha1_file_open_flag) {
default:
fd = open(filename, O_RDONLY);
if (fd >= 0)
break;
/* Fallthrough */
case 0:
return NULL;
}
/* If it failed once, it will probably fail again.
* Stop using O_NOATIME
*/
sha1_file_open_flag = 0;
}
map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
close(fd);
if (map == MAP_FAILED)
return NULL;
*size = st.st_size;
return map;
}
static int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz)
{
unsigned char c;
unsigned int word, bits;
unsigned long size;
static const char *typename[8] = {
NULL, /* OBJ_EXT */
"commit", "tree", "blob", "tag",
NULL, NULL, NULL
};
const char *type;
/* Get the data stream */
memset(stream, 0, sizeof(*stream));
stream->next_in = map;
stream->avail_in = mapsize;
stream->next_out = buffer;
stream->avail_out = bufsiz;
/*
* Is it a zlib-compressed buffer? If so, the first byte
* must be 0x78 (15-bit window size, deflated), and the
* first 16-bit word is evenly divisible by 31
*/
word = (map[0] << 8) + map[1];
if (map[0] == 0x78 && !(word % 31)) {
inflateInit(stream);
return inflate(stream, 0);
}
c = *map++;
mapsize--;
type = typename[(c >> 4) & 7];
if (!type)
return -1;
bits = 4;
size = c & 0xf;
while ((c & 0x80)) {
if (bits >= 8*sizeof(long))
return -1;
c = *map++;
size += (c & 0x7f) << bits;
bits += 7;
mapsize--;
}
/* Set up the stream for the rest.. */
stream->next_in = map;
stream->avail_in = mapsize;
inflateInit(stream);
/* And generate the fake traditional header */
stream->total_out = 1 + snprintf(buffer, bufsiz, "%s %lu", type, size);
return 0;
}
static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size)
{
int bytes = strlen(buffer) + 1;
unsigned char *buf = xmalloc(1+size);
unsigned long n;
n = stream->total_out - bytes;
if (n > size)
n = size;
memcpy(buf, (char *) buffer + bytes, n);
bytes = n;
if (bytes < size) {
stream->next_out = buf + bytes;
stream->avail_out = size - bytes;
while (inflate(stream, Z_FINISH) == Z_OK)
/* nothing */;
}
buf[size] = 0;
inflateEnd(stream);
return buf;
}
/*
* We used to just use "sscanf()", but that's actually way
* too permissive for what we want to check. So do an anal
* object header parse by hand.
*/
static int parse_sha1_header(char *hdr, char *type, unsigned long *sizep)
{
int i;
unsigned long size;
/*
* The type can be at most ten bytes (including the
* terminating '\0' that we add), and is followed by
* a space.
*/
i = 10;
for (;;) {
char c = *hdr++;
if (c == ' ')
break;
if (!--i)
return -1;
*type++ = c;
}
*type = 0;
/*
* The length must follow immediately, and be in canonical
* decimal format (ie "010" is not valid).
*/
size = *hdr++ - '0';
if (size > 9)
return -1;
if (size) {
for (;;) {
unsigned long c = *hdr - '0';
if (c > 9)
break;
hdr++;
size = size * 10 + c;
}
}
*sizep = size;
/*
* The length must be followed by a zero byte
*/
return *hdr ? -1 : 0;
}
void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned long *size)
{
int ret;
z_stream stream;
char hdr[8192];
ret = unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr));
if (ret < Z_OK || parse_sha1_header(hdr, type, size) < 0)
return NULL;
return unpack_sha1_rest(&stream, hdr, *size);
}
/* forward declaration for a mutually recursive function */
static int packed_object_info(struct pack_entry *entry,
char *type, unsigned long *sizep);
static int packed_delta_info(unsigned char *base_sha1,
unsigned long delta_size,
unsigned long left,
char *type,
unsigned long *sizep,
struct packed_git *p)
{
struct pack_entry base_ent;
if (left < 20)
die("truncated pack file");
/* The base entry _must_ be in the same pack */
if (!find_pack_entry_one(base_sha1, &base_ent, p))
die("failed to find delta-pack base object %s",
sha1_to_hex(base_sha1));
/* We choose to only get the type of the base object and
* ignore potentially corrupt pack file that expects the delta
* based on a base with a wrong size. This saves tons of
* inflate() calls.
*/
if (packed_object_info(&base_ent, type, NULL))
die("cannot get info for delta-pack base");
if (sizep) {
const unsigned char *data;
unsigned char delta_head[64];
unsigned long result_size;
z_stream stream;
int st;
memset(&stream, 0, sizeof(stream));
data = stream.next_in = base_sha1 + 20;
stream.avail_in = left - 20;
stream.next_out = delta_head;
stream.avail_out = sizeof(delta_head);
inflateInit(&stream);
st = inflate(&stream, Z_FINISH);
inflateEnd(&stream);
if ((st != Z_STREAM_END) &&
stream.total_out != sizeof(delta_head))
die("delta data unpack-initial failed");
/* Examine the initial part of the delta to figure out
* the result size.
*/
data = delta_head;
/* ignore base size */
get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
/* Read the result size */
result_size = get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
*sizep = result_size;
}
return 0;
}
static unsigned long unpack_object_header(struct packed_git *p, unsigned long offset,
enum object_type *type, unsigned long *sizep)
{
unsigned shift;
unsigned char *pack, c;
unsigned long size;
if (offset >= p->pack_size)
die("object offset outside of pack file");
pack = (unsigned char *) p->pack_base + offset;
c = *pack++;
offset++;
*type = (c >> 4) & 7;
size = c & 15;
shift = 4;
while (c & 0x80) {
if (offset >= p->pack_size)
die("object offset outside of pack file");
c = *pack++;
offset++;
size += (c & 0x7f) << shift;
shift += 7;
}
*sizep = size;
return offset;
}
int check_reuse_pack_delta(struct packed_git *p, unsigned long offset,
unsigned char *base, unsigned long *sizep,
enum object_type *kindp)
{
unsigned long ptr;
int status = -1;
use_packed_git(p);
ptr = offset;
ptr = unpack_object_header(p, ptr, kindp, sizep);
if (*kindp != OBJ_DELTA)
goto done;
memcpy(base, (char *) p->pack_base + ptr, 20);
status = 0;
done:
unuse_packed_git(p);
return status;
}
void packed_object_info_detail(struct pack_entry *e,
char *type,
unsigned long *size,
unsigned long *store_size,
unsigned int *delta_chain_length,
unsigned char *base_sha1)
{
struct packed_git *p = e->p;
unsigned long offset;
unsigned char *pack;
enum object_type kind;
offset = unpack_object_header(p, e->offset, &kind, size);
pack = (unsigned char *) p->pack_base + offset;
if (kind != OBJ_DELTA)
*delta_chain_length = 0;
else {
unsigned int chain_length = 0;
if (p->pack_size <= offset + 20)
die("pack file %s records an incomplete delta base",
p->pack_name);
memcpy(base_sha1, pack, 20);
do {
struct pack_entry base_ent;
unsigned long junk;
find_pack_entry_one(pack, &base_ent, p);
offset = unpack_object_header(p, base_ent.offset,
&kind, &junk);
pack = (unsigned char *) p->pack_base + offset;
chain_length++;
} while (kind == OBJ_DELTA);
*delta_chain_length = chain_length;
}
switch (kind) {
case OBJ_COMMIT:
strcpy(type, commit_type);
break;
case OBJ_TREE:
strcpy(type, tree_type);
break;
case OBJ_BLOB:
strcpy(type, blob_type);
break;
case OBJ_TAG:
strcpy(type, tag_type);
break;
default:
die("corrupted pack file %s containing object of kind %d",
p->pack_name, kind);
}
*store_size = 0; /* notyet */
}
static int packed_object_info(struct pack_entry *entry,
char *type, unsigned long *sizep)
{
struct packed_git *p = entry->p;
unsigned long offset, size, left;