a31c6d022e
Coda doesn't like cross-directory hardlinks. So try to fall back on a plain rename instead.
473 lines
9.9 KiB
C
473 lines
9.9 KiB
C
/*
|
|
* GIT - The information manager from hell
|
|
*
|
|
* Copyright (C) Linus Torvalds, 2005
|
|
*
|
|
* This handles basic git sha1 object files - packing, unpacking,
|
|
* creation etc.
|
|
*/
|
|
#include <stdarg.h>
|
|
#include "cache.h"
|
|
|
|
const char *sha1_file_directory = NULL;
|
|
|
|
#ifndef O_NOATIME
|
|
#if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
|
|
#define O_NOATIME 01000000
|
|
#else
|
|
#define O_NOATIME 0
|
|
#endif
|
|
#endif
|
|
|
|
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 get_sha1_file(const char *path, unsigned char *result)
|
|
{
|
|
char buffer[60];
|
|
int fd = open(path, O_RDONLY);
|
|
int len;
|
|
|
|
if (fd < 0)
|
|
return -1;
|
|
len = read(fd, buffer, sizeof(buffer));
|
|
close(fd);
|
|
if (len < 40)
|
|
return -1;
|
|
return get_sha1_hex(buffer, result);
|
|
}
|
|
|
|
int get_sha1(const char *str, unsigned char *sha1)
|
|
{
|
|
static char pathname[PATH_MAX];
|
|
static const char *prefix[] = {
|
|
"",
|
|
"refs",
|
|
"refs/tags",
|
|
"refs/heads",
|
|
"refs/snap",
|
|
NULL
|
|
};
|
|
const char *gitdir;
|
|
const char **p;
|
|
|
|
if (!get_sha1_hex(str, sha1))
|
|
return 0;
|
|
|
|
gitdir = ".git";
|
|
for (p = prefix; *p; p++) {
|
|
snprintf(pathname, sizeof(pathname), "%s/%s/%s", gitdir, *p, str);
|
|
if (!get_sha1_file(pathname, sha1))
|
|
return 0;
|
|
}
|
|
|
|
return -1;
|
|
}
|
|
|
|
char * sha1_to_hex(const unsigned char *sha1)
|
|
{
|
|
static char buffer[50];
|
|
static const char hex[] = "0123456789abcdef";
|
|
char *buf = buffer;
|
|
int i;
|
|
|
|
for (i = 0; i < 20; i++) {
|
|
unsigned int val = *sha1++;
|
|
*buf++ = hex[val >> 4];
|
|
*buf++ = hex[val & 0xf];
|
|
}
|
|
return buffer;
|
|
}
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
char *sha1_file_name(const unsigned char *sha1)
|
|
{
|
|
int i;
|
|
static char *name, *base;
|
|
|
|
if (!base) {
|
|
char *sha1_file_directory = getenv(DB_ENVIRONMENT) ? : DEFAULT_DB_ENVIRONMENT;
|
|
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;
|
|
}
|
|
for (i = 0; i < 20; i++) {
|
|
static char hex[] = "0123456789abcdef";
|
|
unsigned int val = sha1[i];
|
|
char *pos = name + i*2 + (i > 0);
|
|
*pos++ = hex[val >> 4];
|
|
*pos = hex[val & 0xf];
|
|
}
|
|
return base;
|
|
}
|
|
|
|
int check_sha1_signature(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;
|
|
}
|
|
|
|
void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
|
|
{
|
|
char *filename = sha1_file_name(sha1);
|
|
struct stat st;
|
|
void *map;
|
|
int fd;
|
|
|
|
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:
|
|
perror(filename);
|
|
return NULL;
|
|
}
|
|
|
|
/* If it failed once, it will probably fail again. Stop using O_NOATIME */
|
|
sha1_file_open_flag = 0;
|
|
}
|
|
if (fstat(fd, &st) < 0) {
|
|
close(fd);
|
|
return NULL;
|
|
}
|
|
map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
|
|
close(fd);
|
|
if (-1 == (int)(long)map)
|
|
return NULL;
|
|
*size = st.st_size;
|
|
return map;
|
|
}
|
|
|
|
void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned long *size)
|
|
{
|
|
int ret, bytes;
|
|
z_stream stream;
|
|
char buffer[8192];
|
|
char *buf;
|
|
|
|
/* Get the data stream */
|
|
memset(&stream, 0, sizeof(stream));
|
|
stream.next_in = map;
|
|
stream.avail_in = mapsize;
|
|
stream.next_out = buffer;
|
|
stream.avail_out = sizeof(buffer);
|
|
|
|
inflateInit(&stream);
|
|
ret = inflate(&stream, 0);
|
|
if (ret < Z_OK)
|
|
return NULL;
|
|
if (sscanf(buffer, "%10s %lu", type, size) != 2)
|
|
return NULL;
|
|
|
|
bytes = strlen(buffer) + 1;
|
|
buf = xmalloc(*size);
|
|
|
|
memcpy(buf, buffer + bytes, stream.total_out - bytes);
|
|
bytes = stream.total_out - bytes;
|
|
if (bytes < *size && ret == Z_OK) {
|
|
stream.next_out = buf + bytes;
|
|
stream.avail_out = *size - bytes;
|
|
while (inflate(&stream, Z_FINISH) == Z_OK)
|
|
/* nothing */;
|
|
}
|
|
inflateEnd(&stream);
|
|
return buf;
|
|
}
|
|
|
|
void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size)
|
|
{
|
|
unsigned long mapsize;
|
|
void *map, *buf;
|
|
|
|
map = map_sha1_file(sha1, &mapsize);
|
|
if (map) {
|
|
buf = unpack_sha1_file(map, mapsize, type, size);
|
|
munmap(map, mapsize);
|
|
return buf;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
void *read_object_with_reference(const unsigned char *sha1,
|
|
const unsigned char *required_type,
|
|
unsigned long *size,
|
|
unsigned char *actual_sha1_return)
|
|
{
|
|
char type[20];
|
|
void *buffer;
|
|
unsigned long isize;
|
|
unsigned char actual_sha1[20];
|
|
|
|
memcpy(actual_sha1, sha1, 20);
|
|
while (1) {
|
|
int ref_length = -1;
|
|
const char *ref_type = NULL;
|
|
|
|
buffer = read_sha1_file(actual_sha1, type, &isize);
|
|
if (!buffer)
|
|
return NULL;
|
|
if (!strcmp(type, required_type)) {
|
|
*size = isize;
|
|
if (actual_sha1_return)
|
|
memcpy(actual_sha1_return, actual_sha1, 20);
|
|
return buffer;
|
|
}
|
|
/* Handle references */
|
|
else if (!strcmp(type, "commit"))
|
|
ref_type = "tree ";
|
|
else if (!strcmp(type, "tag"))
|
|
ref_type = "object ";
|
|
else {
|
|
free(buffer);
|
|
return NULL;
|
|
}
|
|
ref_length = strlen(ref_type);
|
|
|
|
if (memcmp(buffer, ref_type, ref_length) ||
|
|
get_sha1_hex(buffer + ref_length, actual_sha1)) {
|
|
free(buffer);
|
|
return NULL;
|
|
}
|
|
/* Now we have the ID of the referred-to object in
|
|
* actual_sha1. Check again. */
|
|
}
|
|
}
|
|
|
|
int write_sha1_file(char *buf, unsigned long len, const char *type, unsigned char *returnsha1)
|
|
{
|
|
int size;
|
|
char *compressed;
|
|
z_stream stream;
|
|
unsigned char sha1[20];
|
|
SHA_CTX c;
|
|
char *filename;
|
|
static char tmpfile[PATH_MAX];
|
|
char hdr[50];
|
|
int fd, hdrlen, ret;
|
|
|
|
/* Generate the header */
|
|
hdrlen = sprintf(hdr, "%s %lu", type, len)+1;
|
|
|
|
/* Sha1.. */
|
|
SHA1_Init(&c);
|
|
SHA1_Update(&c, hdr, hdrlen);
|
|
SHA1_Update(&c, buf, len);
|
|
SHA1_Final(sha1, &c);
|
|
|
|
if (returnsha1)
|
|
memcpy(returnsha1, sha1, 20);
|
|
|
|
filename = sha1_file_name(sha1);
|
|
fd = open(filename, O_RDONLY);
|
|
if (fd >= 0) {
|
|
/*
|
|
* FIXME!!! We might do collision checking here, but we'd
|
|
* need to uncompress the old file and check it. Later.
|
|
*/
|
|
close(fd);
|
|
return 0;
|
|
}
|
|
|
|
if (errno != ENOENT) {
|
|
fprintf(stderr, "sha1 file %s: %s", filename, strerror(errno));
|
|
return -1;
|
|
}
|
|
|
|
snprintf(tmpfile, sizeof(tmpfile), "%s/obj_XXXXXX", get_object_directory());
|
|
fd = mkstemp(tmpfile);
|
|
if (fd < 0) {
|
|
fprintf(stderr, "unable to create temporary sha1 filename %s: %s", tmpfile, strerror(errno));
|
|
return -1;
|
|
}
|
|
|
|
/* Set it up */
|
|
memset(&stream, 0, sizeof(stream));
|
|
deflateInit(&stream, Z_BEST_COMPRESSION);
|
|
size = deflateBound(&stream, len+hdrlen);
|
|
compressed = xmalloc(size);
|
|
|
|
/* Compress it */
|
|
stream.next_out = compressed;
|
|
stream.avail_out = size;
|
|
|
|
/* First header.. */
|
|
stream.next_in = hdr;
|
|
stream.avail_in = hdrlen;
|
|
while (deflate(&stream, 0) == Z_OK)
|
|
/* nothing */
|
|
|
|
/* Then the data itself.. */
|
|
stream.next_in = buf;
|
|
stream.avail_in = len;
|
|
while (deflate(&stream, Z_FINISH) == Z_OK)
|
|
/* nothing */;
|
|
deflateEnd(&stream);
|
|
size = stream.total_out;
|
|
|
|
if (write(fd, compressed, size) != size)
|
|
die("unable to write file");
|
|
fchmod(fd, 0444);
|
|
close(fd);
|
|
|
|
ret = link(tmpfile, filename);
|
|
if (ret < 0) {
|
|
ret = errno;
|
|
|
|
/*
|
|
* Coda hack - coda doesn't like cross-directory links,
|
|
* so we fall back to a rename, which will mean that it
|
|
* won't be able to check collisions, but that's not a
|
|
* big deal.
|
|
*
|
|
* When this succeeds, we just return 0. We have nothing
|
|
* left to unlink.
|
|
*/
|
|
if (ret == EXDEV && !rename(tmpfile, filename))
|
|
return 0;
|
|
}
|
|
unlink(tmpfile);
|
|
if (ret) {
|
|
if (ret != EEXIST) {
|
|
fprintf(stderr, "unable to write sha1 filename %s: %s", filename, strerror(ret));
|
|
return -1;
|
|
}
|
|
/* FIXME!!! Collision check here ? */
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int write_sha1_from_fd(const unsigned char *sha1, int fd)
|
|
{
|
|
char *filename = sha1_file_name(sha1);
|
|
|
|
int local;
|
|
z_stream stream;
|
|
unsigned char real_sha1[20];
|
|
char buf[4096];
|
|
char discard[4096];
|
|
int ret;
|
|
SHA_CTX c;
|
|
|
|
local = open(filename, O_WRONLY | O_CREAT | O_EXCL, 0666);
|
|
|
|
if (local < 0)
|
|
return error("Couldn't open %s\n", filename);
|
|
|
|
memset(&stream, 0, sizeof(stream));
|
|
|
|
inflateInit(&stream);
|
|
|
|
SHA1_Init(&c);
|
|
|
|
do {
|
|
ssize_t size;
|
|
size = read(fd, buf, 4096);
|
|
if (size <= 0) {
|
|
close(local);
|
|
unlink(filename);
|
|
if (!size)
|
|
return error("Connection closed?");
|
|
perror("Reading from connection");
|
|
return -1;
|
|
}
|
|
write(local, buf, size);
|
|
stream.avail_in = size;
|
|
stream.next_in = buf;
|
|
do {
|
|
stream.next_out = discard;
|
|
stream.avail_out = sizeof(discard);
|
|
ret = inflate(&stream, Z_SYNC_FLUSH);
|
|
SHA1_Update(&c, discard, sizeof(discard) -
|
|
stream.avail_out);
|
|
} while (stream.avail_in && ret == Z_OK);
|
|
|
|
} while (ret == Z_OK);
|
|
inflateEnd(&stream);
|
|
|
|
close(local);
|
|
SHA1_Final(real_sha1, &c);
|
|
if (ret != Z_STREAM_END) {
|
|
unlink(filename);
|
|
return error("File %s corrupted", sha1_to_hex(sha1));
|
|
}
|
|
if (memcmp(sha1, real_sha1, 20)) {
|
|
unlink(filename);
|
|
return error("File %s has bad hash\n", sha1_to_hex(sha1));
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int has_sha1_file(const unsigned char *sha1)
|
|
{
|
|
char *filename = sha1_file_name(sha1);
|
|
struct stat st;
|
|
|
|
if (!stat(filename, &st))
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
int index_fd(unsigned char *sha1, int fd, struct stat *st)
|
|
{
|
|
unsigned long size = st->st_size;
|
|
void *buf;
|
|
int ret;
|
|
|
|
buf = "";
|
|
if (size)
|
|
buf = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
|
|
close(fd);
|
|
if ((int)(long)buf == -1)
|
|
return -1;
|
|
|
|
ret = write_sha1_file(buf, size, "blob", sha1);
|
|
if (size)
|
|
munmap(buf, size);
|
|
return ret;
|
|
}
|