зеркало из https://github.com/microsoft/git.git
1894 строки
44 KiB
C
1894 строки
44 KiB
C
/*
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* GIT - The information manager from hell
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*
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* Copyright (C) Linus Torvalds, 2005
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*
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* This handles basic git sha1 object files - packing, unpacking,
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* creation etc.
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*/
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#include "cache.h"
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#include "delta.h"
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#include "pack.h"
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#include "blob.h"
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#include "commit.h"
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#include "tag.h"
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#include "tree.h"
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#ifndef O_NOATIME
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#if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
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#define O_NOATIME 01000000
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#else
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#define O_NOATIME 0
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#endif
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#endif
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const unsigned char null_sha1[20];
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static unsigned int sha1_file_open_flag = O_NOATIME;
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signed char hexval_table[256] = {
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-1, -1, -1, -1, -1, -1, -1, -1, /* 00-07 */
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-1, -1, -1, -1, -1, -1, -1, -1, /* 08-0f */
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-1, -1, -1, -1, -1, -1, -1, -1, /* 10-17 */
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-1, -1, -1, -1, -1, -1, -1, -1, /* 18-1f */
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-1, -1, -1, -1, -1, -1, -1, -1, /* 20-27 */
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-1, -1, -1, -1, -1, -1, -1, -1, /* 28-2f */
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0, 1, 2, 3, 4, 5, 6, 7, /* 30-37 */
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8, 9, -1, -1, -1, -1, -1, -1, /* 38-3f */
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-1, 10, 11, 12, 13, 14, 15, -1, /* 40-47 */
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-1, -1, -1, -1, -1, -1, -1, -1, /* 48-4f */
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-1, -1, -1, -1, -1, -1, -1, -1, /* 50-57 */
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-1, -1, -1, -1, -1, -1, -1, -1, /* 58-5f */
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-1, 10, 11, 12, 13, 14, 15, -1, /* 60-67 */
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-1, -1, -1, -1, -1, -1, -1, -1, /* 68-67 */
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-1, -1, -1, -1, -1, -1, -1, -1, /* 70-77 */
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-1, -1, -1, -1, -1, -1, -1, -1, /* 78-7f */
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-1, -1, -1, -1, -1, -1, -1, -1, /* 80-87 */
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-1, -1, -1, -1, -1, -1, -1, -1, /* 88-8f */
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-1, -1, -1, -1, -1, -1, -1, -1, /* 90-97 */
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-1, -1, -1, -1, -1, -1, -1, -1, /* 98-9f */
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-1, -1, -1, -1, -1, -1, -1, -1, /* a0-a7 */
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-1, -1, -1, -1, -1, -1, -1, -1, /* a8-af */
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-1, -1, -1, -1, -1, -1, -1, -1, /* b0-b7 */
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-1, -1, -1, -1, -1, -1, -1, -1, /* b8-bf */
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-1, -1, -1, -1, -1, -1, -1, -1, /* c0-c7 */
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-1, -1, -1, -1, -1, -1, -1, -1, /* c8-cf */
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-1, -1, -1, -1, -1, -1, -1, -1, /* d0-d7 */
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-1, -1, -1, -1, -1, -1, -1, -1, /* d8-df */
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-1, -1, -1, -1, -1, -1, -1, -1, /* e0-e7 */
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-1, -1, -1, -1, -1, -1, -1, -1, /* e8-ef */
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-1, -1, -1, -1, -1, -1, -1, -1, /* f0-f7 */
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-1, -1, -1, -1, -1, -1, -1, -1, /* f8-ff */
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};
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int get_sha1_hex(const char *hex, unsigned char *sha1)
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{
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int i;
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for (i = 0; i < 20; i++) {
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unsigned int val = (hexval(hex[0]) << 4) | hexval(hex[1]);
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if (val & ~0xff)
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return -1;
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*sha1++ = val;
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hex += 2;
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}
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return 0;
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}
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int safe_create_leading_directories(char *path)
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{
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char *pos = path;
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struct stat st;
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if (*pos == '/')
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pos++;
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while (pos) {
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pos = strchr(pos, '/');
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if (!pos)
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break;
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*pos = 0;
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if (!stat(path, &st)) {
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/* path exists */
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if (!S_ISDIR(st.st_mode)) {
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*pos = '/';
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return -3;
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}
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}
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else if (mkdir(path, 0777)) {
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*pos = '/';
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return -1;
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}
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else if (adjust_shared_perm(path)) {
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*pos = '/';
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return -2;
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}
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*pos++ = '/';
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}
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return 0;
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}
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char * sha1_to_hex(const unsigned char *sha1)
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{
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static int bufno;
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static char hexbuffer[4][50];
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static const char hex[] = "0123456789abcdef";
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char *buffer = hexbuffer[3 & ++bufno], *buf = buffer;
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int i;
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for (i = 0; i < 20; i++) {
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unsigned int val = *sha1++;
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*buf++ = hex[val >> 4];
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*buf++ = hex[val & 0xf];
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}
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*buf = '\0';
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return buffer;
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}
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static void fill_sha1_path(char *pathbuf, const unsigned char *sha1)
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{
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int i;
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for (i = 0; i < 20; i++) {
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static char hex[] = "0123456789abcdef";
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unsigned int val = sha1[i];
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char *pos = pathbuf + i*2 + (i > 0);
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*pos++ = hex[val >> 4];
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*pos = hex[val & 0xf];
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}
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}
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/*
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* NOTE! This returns a statically allocated buffer, so you have to be
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* careful about using it. Do a "xstrdup()" if you need to save the
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* filename.
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*
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* Also note that this returns the location for creating. Reading
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* SHA1 file can happen from any alternate directory listed in the
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* DB_ENVIRONMENT environment variable if it is not found in
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* the primary object database.
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*/
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char *sha1_file_name(const unsigned char *sha1)
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{
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static char *name, *base;
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if (!base) {
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const char *sha1_file_directory = get_object_directory();
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int len = strlen(sha1_file_directory);
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base = xmalloc(len + 60);
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memcpy(base, sha1_file_directory, len);
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memset(base+len, 0, 60);
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base[len] = '/';
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base[len+3] = '/';
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name = base + len + 1;
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}
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fill_sha1_path(name, sha1);
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return base;
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}
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char *sha1_pack_name(const unsigned char *sha1)
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{
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static const char hex[] = "0123456789abcdef";
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static char *name, *base, *buf;
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int i;
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if (!base) {
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const char *sha1_file_directory = get_object_directory();
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int len = strlen(sha1_file_directory);
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base = xmalloc(len + 60);
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sprintf(base, "%s/pack/pack-1234567890123456789012345678901234567890.pack", sha1_file_directory);
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name = base + len + 11;
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}
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buf = name;
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for (i = 0; i < 20; i++) {
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unsigned int val = *sha1++;
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*buf++ = hex[val >> 4];
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*buf++ = hex[val & 0xf];
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}
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return base;
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}
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char *sha1_pack_index_name(const unsigned char *sha1)
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{
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static const char hex[] = "0123456789abcdef";
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static char *name, *base, *buf;
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int i;
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if (!base) {
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const char *sha1_file_directory = get_object_directory();
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int len = strlen(sha1_file_directory);
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base = xmalloc(len + 60);
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sprintf(base, "%s/pack/pack-1234567890123456789012345678901234567890.idx", sha1_file_directory);
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name = base + len + 11;
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}
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buf = name;
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for (i = 0; i < 20; i++) {
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unsigned int val = *sha1++;
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*buf++ = hex[val >> 4];
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*buf++ = hex[val & 0xf];
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}
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return base;
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}
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struct alternate_object_database *alt_odb_list;
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static struct alternate_object_database **alt_odb_tail;
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static void read_info_alternates(const char * alternates, int depth);
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/*
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* Prepare alternate object database registry.
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*
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* The variable alt_odb_list points at the list of struct
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* alternate_object_database. The elements on this list come from
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* non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
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* environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
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* whose contents is similar to that environment variable but can be
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* LF separated. Its base points at a statically allocated buffer that
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* contains "/the/directory/corresponding/to/.git/objects/...", while
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* its name points just after the slash at the end of ".git/objects/"
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* in the example above, and has enough space to hold 40-byte hex
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* SHA1, an extra slash for the first level indirection, and the
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* terminating NUL.
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*/
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static int link_alt_odb_entry(const char * entry, int len, const char * relative_base, int depth)
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{
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struct stat st;
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const char *objdir = get_object_directory();
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struct alternate_object_database *ent;
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struct alternate_object_database *alt;
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/* 43 = 40-byte + 2 '/' + terminating NUL */
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int pfxlen = len;
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int entlen = pfxlen + 43;
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int base_len = -1;
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if (*entry != '/' && relative_base) {
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/* Relative alt-odb */
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if (base_len < 0)
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base_len = strlen(relative_base) + 1;
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entlen += base_len;
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pfxlen += base_len;
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}
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ent = xmalloc(sizeof(*ent) + entlen);
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if (*entry != '/' && relative_base) {
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memcpy(ent->base, relative_base, base_len - 1);
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ent->base[base_len - 1] = '/';
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memcpy(ent->base + base_len, entry, len);
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}
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else
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memcpy(ent->base, entry, pfxlen);
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ent->name = ent->base + pfxlen + 1;
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ent->base[pfxlen + 3] = '/';
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ent->base[pfxlen] = ent->base[entlen-1] = 0;
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/* Detect cases where alternate disappeared */
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if (stat(ent->base, &st) || !S_ISDIR(st.st_mode)) {
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error("object directory %s does not exist; "
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"check .git/objects/info/alternates.",
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ent->base);
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free(ent);
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return -1;
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}
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/* Prevent the common mistake of listing the same
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* thing twice, or object directory itself.
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*/
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for (alt = alt_odb_list; alt; alt = alt->next) {
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if (!memcmp(ent->base, alt->base, pfxlen)) {
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free(ent);
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return -1;
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}
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}
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if (!memcmp(ent->base, objdir, pfxlen)) {
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free(ent);
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return -1;
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}
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/* add the alternate entry */
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*alt_odb_tail = ent;
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alt_odb_tail = &(ent->next);
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ent->next = NULL;
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/* recursively add alternates */
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read_info_alternates(ent->base, depth + 1);
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ent->base[pfxlen] = '/';
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return 0;
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}
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static void link_alt_odb_entries(const char *alt, const char *ep, int sep,
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const char *relative_base, int depth)
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{
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const char *cp, *last;
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if (depth > 5) {
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error("%s: ignoring alternate object stores, nesting too deep.",
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relative_base);
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return;
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}
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last = alt;
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while (last < ep) {
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cp = last;
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if (cp < ep && *cp == '#') {
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while (cp < ep && *cp != sep)
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cp++;
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last = cp + 1;
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continue;
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}
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while (cp < ep && *cp != sep)
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cp++;
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if (last != cp) {
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if ((*last != '/') && depth) {
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error("%s: ignoring relative alternate object store %s",
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relative_base, last);
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} else {
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link_alt_odb_entry(last, cp - last,
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relative_base, depth);
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}
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}
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while (cp < ep && *cp == sep)
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cp++;
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last = cp;
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}
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}
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static void read_info_alternates(const char * relative_base, int depth)
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{
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char *map;
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struct stat st;
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char path[PATH_MAX];
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int fd;
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sprintf(path, "%s/info/alternates", relative_base);
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fd = open(path, O_RDONLY);
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if (fd < 0)
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return;
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if (fstat(fd, &st) || (st.st_size == 0)) {
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close(fd);
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return;
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}
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map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
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close(fd);
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if (map == MAP_FAILED)
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return;
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link_alt_odb_entries(map, map + st.st_size, '\n', relative_base, depth);
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munmap(map, st.st_size);
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}
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void prepare_alt_odb(void)
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{
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const char *alt;
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alt = getenv(ALTERNATE_DB_ENVIRONMENT);
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if (!alt) alt = "";
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if (alt_odb_tail)
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return;
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alt_odb_tail = &alt_odb_list;
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link_alt_odb_entries(alt, alt + strlen(alt), ':', NULL, 0);
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read_info_alternates(get_object_directory(), 0);
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}
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static char *find_sha1_file(const unsigned char *sha1, struct stat *st)
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{
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char *name = sha1_file_name(sha1);
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struct alternate_object_database *alt;
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if (!stat(name, st))
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return name;
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prepare_alt_odb();
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for (alt = alt_odb_list; alt; alt = alt->next) {
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name = alt->name;
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fill_sha1_path(name, sha1);
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if (!stat(alt->base, st))
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return alt->base;
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}
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return NULL;
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}
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static int pack_used_ctr;
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static unsigned long pack_mapped;
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struct packed_git *packed_git;
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static int check_packed_git_idx(const char *path, unsigned long *idx_size_,
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void **idx_map_)
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{
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void *idx_map;
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unsigned int *index;
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unsigned long idx_size;
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int nr, i;
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int fd = open(path, O_RDONLY);
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struct stat st;
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if (fd < 0)
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return -1;
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if (fstat(fd, &st)) {
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close(fd);
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return -1;
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}
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idx_size = st.st_size;
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idx_map = mmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0);
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close(fd);
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if (idx_map == MAP_FAILED)
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return -1;
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index = idx_map;
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*idx_map_ = idx_map;
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*idx_size_ = idx_size;
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/* check index map */
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if (idx_size < 4*256 + 20 + 20)
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return error("index file too small");
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nr = 0;
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for (i = 0; i < 256; i++) {
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unsigned int n = ntohl(index[i]);
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if (n < nr)
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return error("non-monotonic index");
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nr = n;
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}
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/*
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* Total size:
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* - 256 index entries 4 bytes each
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* - 24-byte entries * nr (20-byte sha1 + 4-byte offset)
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* - 20-byte SHA1 of the packfile
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* - 20-byte SHA1 file checksum
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*/
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if (idx_size != 4*256 + nr * 24 + 20 + 20)
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return error("wrong index file size");
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return 0;
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}
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static int unuse_one_packed_git(void)
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{
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struct packed_git *p, *lru = NULL;
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for (p = packed_git; p; p = p->next) {
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if (!p->windows || p->windows->inuse_cnt)
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continue;
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if (!lru || p->windows->last_used < lru->windows->last_used)
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lru = p;
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}
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if (!lru)
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return 0;
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munmap(lru->windows->base, lru->windows->len);
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free(lru->windows);
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lru->windows = NULL;
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return 1;
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}
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void unuse_packed_git(struct packed_git *p)
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{
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if (p->windows)
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p->windows->inuse_cnt--;
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}
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int use_packed_git(struct packed_git *p)
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{
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if (!p->pack_size) {
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struct stat st;
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/* We created the struct before we had the pack */
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stat(p->pack_name, &st);
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if (!S_ISREG(st.st_mode))
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die("packfile %s not a regular file", p->pack_name);
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p->pack_size = st.st_size;
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}
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if (!p->windows) {
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int fd;
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struct stat st;
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struct pack_window *win;
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struct pack_header *hdr;
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pack_mapped += p->pack_size;
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while (packed_git_limit < pack_mapped && unuse_one_packed_git())
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; /* nothing */
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fd = open(p->pack_name, O_RDONLY);
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if (fd < 0)
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die("packfile %s cannot be opened", p->pack_name);
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if (fstat(fd, &st)) {
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close(fd);
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|
die("packfile %s cannot be opened", p->pack_name);
|
|
}
|
|
if (st.st_size != p->pack_size)
|
|
die("packfile %s size mismatch.", p->pack_name);
|
|
win = xcalloc(1, sizeof(*win));
|
|
win->len = p->pack_size;
|
|
win->base = mmap(NULL, p->pack_size, PROT_READ, MAP_PRIVATE, fd, 0);
|
|
close(fd);
|
|
if (win->base == MAP_FAILED)
|
|
die("packfile %s cannot be mapped.", p->pack_name);
|
|
p->windows = win;
|
|
|
|
/* Check if we understand this pack file. If we don't we're
|
|
* likely too old to handle it.
|
|
*/
|
|
hdr = (struct pack_header*)win->base;
|
|
if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
|
|
die("packfile %s isn't actually a pack.", p->pack_name);
|
|
if (!pack_version_ok(hdr->hdr_version))
|
|
die("packfile %s is version %i and not supported"
|
|
" (try upgrading GIT to a newer version)",
|
|
p->pack_name, ntohl(hdr->hdr_version));
|
|
|
|
/* Check if the pack file matches with the index file.
|
|
* this is cheap.
|
|
*/
|
|
if (hashcmp((unsigned char *)(p->index_base) +
|
|
p->index_size - 40,
|
|
p->windows->base +
|
|
p->pack_size - 20)) {
|
|
die("packfile %s does not match index.", p->pack_name);
|
|
}
|
|
}
|
|
p->windows->last_used = pack_used_ctr++;
|
|
p->windows->inuse_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->windows = NULL;
|
|
p->pack_local = local;
|
|
if ((path_len > 44) && !get_sha1_hex(path + path_len - 44, sha1))
|
|
hashcpy(p->sha1, sha1);
|
|
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->windows = NULL;
|
|
hashcpy(p->sha1, sha1);
|
|
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 (!has_extension(de->d_name, ".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;
|
|
}
|
|
|
|
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)
|
|
{
|
|
unsigned char real_sha1[20];
|
|
hash_sha1_file(map, size, type, real_sha1);
|
|
return hashcmp(sha1, real_sha1) ? -1 : 0;
|
|
}
|
|
|
|
void *map_sha1_file(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;
|
|
}
|
|
|
|
int legacy_loose_object(unsigned char *map)
|
|
{
|
|
unsigned int word;
|
|
|
|
/*
|
|
* 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))
|
|
return 1;
|
|
else
|
|
return 0;
|
|
}
|
|
|
|
unsigned long unpack_object_header_gently(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep)
|
|
{
|
|
unsigned shift;
|
|
unsigned char c;
|
|
unsigned long size;
|
|
unsigned long used = 0;
|
|
|
|
c = buf[used++];
|
|
*type = (c >> 4) & 7;
|
|
size = c & 15;
|
|
shift = 4;
|
|
while (c & 0x80) {
|
|
if (len <= used)
|
|
return 0;
|
|
if (sizeof(long) * 8 <= shift)
|
|
return 0;
|
|
c = buf[used++];
|
|
size += (c & 0x7f) << shift;
|
|
shift += 7;
|
|
}
|
|
*sizep = size;
|
|
return used;
|
|
}
|
|
|
|
static int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz)
|
|
{
|
|
unsigned long size, used;
|
|
static const char valid_loose_object_type[8] = {
|
|
0, /* OBJ_EXT */
|
|
1, 1, 1, 1, /* "commit", "tree", "blob", "tag" */
|
|
0, /* "delta" and others are invalid in a loose object */
|
|
};
|
|
enum object_type 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;
|
|
|
|
if (legacy_loose_object(map)) {
|
|
inflateInit(stream);
|
|
return inflate(stream, 0);
|
|
}
|
|
|
|
used = unpack_object_header_gently(map, mapsize, &type, &size);
|
|
if (!used || !valid_loose_object_type[type])
|
|
return -1;
|
|
map += used;
|
|
mapsize -= used;
|
|
|
|
/* 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_names[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);
|
|
}
|
|
|
|
static unsigned long get_delta_base(struct packed_git *p,
|
|
unsigned long offset,
|
|
enum object_type kind,
|
|
unsigned long delta_obj_offset,
|
|
unsigned long *base_obj_offset)
|
|
{
|
|
unsigned char *base_info = p->windows->base + offset;
|
|
unsigned long base_offset;
|
|
|
|
/* there must be at least 20 bytes left regardless of delta type */
|
|
if (p->pack_size <= offset + 20)
|
|
die("truncated pack file");
|
|
|
|
if (kind == OBJ_OFS_DELTA) {
|
|
unsigned used = 0;
|
|
unsigned char c = base_info[used++];
|
|
base_offset = c & 127;
|
|
while (c & 128) {
|
|
base_offset += 1;
|
|
if (!base_offset || base_offset & ~(~0UL >> 7))
|
|
die("offset value overflow for delta base object");
|
|
c = base_info[used++];
|
|
base_offset = (base_offset << 7) + (c & 127);
|
|
}
|
|
base_offset = delta_obj_offset - base_offset;
|
|
if (base_offset >= delta_obj_offset)
|
|
die("delta base offset out of bound");
|
|
offset += used;
|
|
} else if (kind == OBJ_REF_DELTA) {
|
|
/* The base entry _must_ be in the same pack */
|
|
base_offset = find_pack_entry_one(base_info, p);
|
|
if (!base_offset)
|
|
die("failed to find delta-pack base object %s",
|
|
sha1_to_hex(base_info));
|
|
offset += 20;
|
|
} else
|
|
die("I am totally screwed");
|
|
*base_obj_offset = base_offset;
|
|
return offset;
|
|
}
|
|
|
|
/* forward declaration for a mutually recursive function */
|
|
static int packed_object_info(struct packed_git *p, unsigned long offset,
|
|
char *type, unsigned long *sizep);
|
|
|
|
static int packed_delta_info(struct packed_git *p,
|
|
unsigned long offset,
|
|
enum object_type kind,
|
|
unsigned long obj_offset,
|
|
char *type,
|
|
unsigned long *sizep)
|
|
{
|
|
unsigned long base_offset;
|
|
|
|
offset = get_delta_base(p, offset, kind, obj_offset, &base_offset);
|
|
|
|
/* 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(p, base_offset, type, NULL))
|
|
die("cannot get info for delta-pack base");
|
|
|
|
if (sizep) {
|
|
const unsigned char *data;
|
|
unsigned char delta_head[20];
|
|
unsigned long result_size;
|
|
z_stream stream;
|
|
int st;
|
|
|
|
memset(&stream, 0, sizeof(stream));
|
|
|
|
stream.next_in = p->windows->base + offset;
|
|
stream.avail_in = p->pack_size - offset;
|
|
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 long used;
|
|
|
|
if (p->pack_size <= offset)
|
|
die("object offset outside of pack file");
|
|
|
|
used = unpack_object_header_gently(p->windows->base + offset,
|
|
p->pack_size - offset, type, sizep);
|
|
if (!used)
|
|
die("object offset outside of pack file");
|
|
|
|
return offset + used;
|
|
}
|
|
|
|
void packed_object_info_detail(struct packed_git *p,
|
|
unsigned long offset,
|
|
char *type,
|
|
unsigned long *size,
|
|
unsigned long *store_size,
|
|
unsigned int *delta_chain_length,
|
|
unsigned char *base_sha1)
|
|
{
|
|
unsigned long obj_offset, val;
|
|
unsigned char *next_sha1;
|
|
enum object_type kind;
|
|
|
|
*delta_chain_length = 0;
|
|
obj_offset = offset;
|
|
offset = unpack_object_header(p, offset, &kind, size);
|
|
|
|
for (;;) {
|
|
switch (kind) {
|
|
default:
|
|
die("pack %s contains unknown object type %d",
|
|
p->pack_name, kind);
|
|
case OBJ_COMMIT:
|
|
case OBJ_TREE:
|
|
case OBJ_BLOB:
|
|
case OBJ_TAG:
|
|
strcpy(type, type_names[kind]);
|
|
*store_size = 0; /* notyet */
|
|
return;
|
|
case OBJ_OFS_DELTA:
|
|
get_delta_base(p, offset, kind, obj_offset, &offset);
|
|
if (*delta_chain_length == 0) {
|
|
/* TODO: find base_sha1 as pointed by offset */
|
|
}
|
|
break;
|
|
case OBJ_REF_DELTA:
|
|
if (p->pack_size <= offset + 20)
|
|
die("pack file %s records an incomplete delta base",
|
|
p->pack_name);
|
|
next_sha1 = p->windows->base + offset;
|
|
if (*delta_chain_length == 0)
|
|
hashcpy(base_sha1, next_sha1);
|
|
offset = find_pack_entry_one(next_sha1, p);
|
|
break;
|
|
}
|
|
obj_offset = offset;
|
|
offset = unpack_object_header(p, offset, &kind, &val);
|
|
(*delta_chain_length)++;
|
|
}
|
|
}
|
|
|
|
static int packed_object_info(struct packed_git *p, unsigned long offset,
|
|
char *type, unsigned long *sizep)
|
|
{
|
|
unsigned long size, obj_offset = offset;
|
|
enum object_type kind;
|
|
|
|
offset = unpack_object_header(p, offset, &kind, &size);
|
|
|
|
switch (kind) {
|
|
case OBJ_OFS_DELTA:
|
|
case OBJ_REF_DELTA:
|
|
return packed_delta_info(p, offset, kind, obj_offset, type, sizep);
|
|
case OBJ_COMMIT:
|
|
case OBJ_TREE:
|
|
case OBJ_BLOB:
|
|
case OBJ_TAG:
|
|
strcpy(type, type_names[kind]);
|
|
break;
|
|
default:
|
|
die("pack %s contains unknown object type %d",
|
|
p->pack_name, kind);
|
|
}
|
|
if (sizep)
|
|
*sizep = size;
|
|
return 0;
|
|
}
|
|
|
|
static void *unpack_compressed_entry(struct packed_git *p,
|
|
unsigned long offset,
|
|
unsigned long size)
|
|
{
|
|
int st;
|
|
z_stream stream;
|
|
unsigned char *buffer;
|
|
|
|
buffer = xmalloc(size + 1);
|
|
buffer[size] = 0;
|
|
memset(&stream, 0, sizeof(stream));
|
|
stream.next_in = p->windows->base + offset;
|
|
stream.avail_in = p->pack_size - offset;
|
|
stream.next_out = buffer;
|
|
stream.avail_out = size;
|
|
|
|
inflateInit(&stream);
|
|
st = inflate(&stream, Z_FINISH);
|
|
inflateEnd(&stream);
|
|
if ((st != Z_STREAM_END) || stream.total_out != size) {
|
|
free(buffer);
|
|
return NULL;
|
|
}
|
|
|
|
return buffer;
|
|
}
|
|
|
|
static void *unpack_delta_entry(struct packed_git *p,
|
|
unsigned long offset,
|
|
unsigned long delta_size,
|
|
enum object_type kind,
|
|
unsigned long obj_offset,
|
|
char *type,
|
|
unsigned long *sizep)
|
|
{
|
|
void *delta_data, *result, *base;
|
|
unsigned long result_size, base_size, base_offset;
|
|
|
|
offset = get_delta_base(p, offset, kind, obj_offset, &base_offset);
|
|
base = unpack_entry(p, base_offset, type, &base_size);
|
|
if (!base)
|
|
die("failed to read delta base object at %lu from %s",
|
|
base_offset, p->pack_name);
|
|
|
|
delta_data = unpack_compressed_entry(p, offset, delta_size);
|
|
result = patch_delta(base, base_size,
|
|
delta_data, delta_size,
|
|
&result_size);
|
|
if (!result)
|
|
die("failed to apply delta");
|
|
free(delta_data);
|
|
free(base);
|
|
*sizep = result_size;
|
|
return result;
|
|
}
|
|
|
|
void *unpack_entry(struct packed_git *p, unsigned long offset,
|
|
char *type, unsigned long *sizep)
|
|
{
|
|
unsigned long size, obj_offset = offset;
|
|
enum object_type kind;
|
|
void *retval;
|
|
|
|
if (use_packed_git(p))
|
|
die("cannot map packed file");
|
|
offset = unpack_object_header(p, offset, &kind, &size);
|
|
switch (kind) {
|
|
case OBJ_OFS_DELTA:
|
|
case OBJ_REF_DELTA:
|
|
retval = unpack_delta_entry(p, offset, size, kind, obj_offset, type, sizep);
|
|
break;
|
|
case OBJ_COMMIT:
|
|
case OBJ_TREE:
|
|
case OBJ_BLOB:
|
|
case OBJ_TAG:
|
|
strcpy(type, type_names[kind]);
|
|
*sizep = size;
|
|
retval = unpack_compressed_entry(p, offset, size);
|
|
break;
|
|
default:
|
|
die("unknown object type %i in %s", kind, p->pack_name);
|
|
}
|
|
unuse_packed_git(p);
|
|
return retval;
|
|
}
|
|
|
|
int num_packed_objects(const struct packed_git *p)
|
|
{
|
|
/* See check_packed_git_idx() */
|
|
return (p->index_size - 20 - 20 - 4*256) / 24;
|
|
}
|
|
|
|
int nth_packed_object_sha1(const struct packed_git *p, int n,
|
|
unsigned char* sha1)
|
|
{
|
|
void *index = p->index_base + 256;
|
|
if (n < 0 || num_packed_objects(p) <= n)
|
|
return -1;
|
|
hashcpy(sha1, (unsigned char *) index + (24 * n) + 4);
|
|
return 0;
|
|
}
|
|
|
|
unsigned long find_pack_entry_one(const unsigned char *sha1,
|
|
struct packed_git *p)
|
|
{
|
|
unsigned int *level1_ofs = p->index_base;
|
|
int hi = ntohl(level1_ofs[*sha1]);
|
|
int lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1]));
|
|
void *index = p->index_base + 256;
|
|
|
|
do {
|
|
int mi = (lo + hi) / 2;
|
|
int cmp = hashcmp((unsigned char *)index + (24 * mi) + 4, sha1);
|
|
if (!cmp)
|
|
return ntohl(*((unsigned int *) ((char *) index + (24 * mi))));
|
|
if (cmp > 0)
|
|
hi = mi;
|
|
else
|
|
lo = mi+1;
|
|
} while (lo < hi);
|
|
return 0;
|
|
}
|
|
|
|
static int matches_pack_name(struct packed_git *p, const char *ig)
|
|
{
|
|
const char *last_c, *c;
|
|
|
|
if (!strcmp(p->pack_name, ig))
|
|
return 0;
|
|
|
|
for (c = p->pack_name, last_c = c; *c;)
|
|
if (*c == '/')
|
|
last_c = ++c;
|
|
else
|
|
++c;
|
|
if (!strcmp(last_c, ig))
|
|
return 0;
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e, const char **ignore_packed)
|
|
{
|
|
struct packed_git *p;
|
|
unsigned long offset;
|
|
|
|
prepare_packed_git();
|
|
|
|
for (p = packed_git; p; p = p->next) {
|
|
if (ignore_packed) {
|
|
const char **ig;
|
|
for (ig = ignore_packed; *ig; ig++)
|
|
if (!matches_pack_name(p, *ig))
|
|
break;
|
|
if (*ig)
|
|
continue;
|
|
}
|
|
offset = find_pack_entry_one(sha1, p);
|
|
if (offset) {
|
|
e->offset = offset;
|
|
e->p = p;
|
|
hashcpy(e->sha1, sha1);
|
|
return 1;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
struct packed_git *find_sha1_pack(const unsigned char *sha1,
|
|
struct packed_git *packs)
|
|
{
|
|
struct packed_git *p;
|
|
|
|
for (p = packs; p; p = p->next) {
|
|
if (find_pack_entry_one(sha1, p))
|
|
return p;
|
|
}
|
|
return NULL;
|
|
|
|
}
|
|
|
|
static int sha1_loose_object_info(const unsigned char *sha1, char *type, unsigned long *sizep)
|
|
{
|
|
int status;
|
|
unsigned long mapsize, size;
|
|
void *map;
|
|
z_stream stream;
|
|
char hdr[128];
|
|
|
|
map = map_sha1_file(sha1, &mapsize);
|
|
if (!map)
|
|
return error("unable to find %s", sha1_to_hex(sha1));
|
|
if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
|
|
status = error("unable to unpack %s header",
|
|
sha1_to_hex(sha1));
|
|
if (parse_sha1_header(hdr, type, &size) < 0)
|
|
status = error("unable to parse %s header", sha1_to_hex(sha1));
|
|
else {
|
|
status = 0;
|
|
if (sizep)
|
|
*sizep = size;
|
|
}
|
|
inflateEnd(&stream);
|
|
munmap(map, mapsize);
|
|
return status;
|
|
}
|
|
|
|
int sha1_object_info(const unsigned char *sha1, char *type, unsigned long *sizep)
|
|
{
|
|
int status;
|
|
struct pack_entry e;
|
|
|
|
if (!find_pack_entry(sha1, &e, NULL)) {
|
|
reprepare_packed_git();
|
|
if (!find_pack_entry(sha1, &e, NULL))
|
|
return sha1_loose_object_info(sha1, type, sizep);
|
|
}
|
|
if (use_packed_git(e.p))
|
|
die("cannot map packed file");
|
|
status = packed_object_info(e.p, e.offset, type, sizep);
|
|
unuse_packed_git(e.p);
|
|
return status;
|
|
}
|
|
|
|
static void *read_packed_sha1(const unsigned char *sha1, char *type, unsigned long *size)
|
|
{
|
|
struct pack_entry e;
|
|
|
|
if (!find_pack_entry(sha1, &e, NULL)) {
|
|
error("cannot read sha1_file for %s", sha1_to_hex(sha1));
|
|
return NULL;
|
|
}
|
|
return unpack_entry(e.p, e.offset, type, size);
|
|
}
|
|
|
|
void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size)
|
|
{
|
|
unsigned long mapsize;
|
|
void *map, *buf;
|
|
struct pack_entry e;
|
|
|
|
if (find_pack_entry(sha1, &e, NULL))
|
|
return read_packed_sha1(sha1, type, size);
|
|
map = map_sha1_file(sha1, &mapsize);
|
|
if (map) {
|
|
buf = unpack_sha1_file(map, mapsize, type, size);
|
|
munmap(map, mapsize);
|
|
return buf;
|
|
}
|
|
reprepare_packed_git();
|
|
if (find_pack_entry(sha1, &e, NULL))
|
|
return read_packed_sha1(sha1, type, size);
|
|
return NULL;
|
|
}
|
|
|
|
void *read_object_with_reference(const unsigned char *sha1,
|
|
const char *required_type,
|
|
unsigned long *size,
|
|
unsigned char *actual_sha1_return)
|
|
{
|
|
char type[20];
|
|
void *buffer;
|
|
unsigned long isize;
|
|
unsigned char actual_sha1[20];
|
|
|
|
hashcpy(actual_sha1, sha1);
|
|
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)
|
|
hashcpy(actual_sha1_return, actual_sha1);
|
|
return buffer;
|
|
}
|
|
/* Handle references */
|
|
else if (!strcmp(type, commit_type))
|
|
ref_type = "tree ";
|
|
else if (!strcmp(type, tag_type))
|
|
ref_type = "object ";
|
|
else {
|
|
free(buffer);
|
|
return NULL;
|
|
}
|
|
ref_length = strlen(ref_type);
|
|
|
|
if (memcmp(buffer, ref_type, ref_length) ||
|
|
get_sha1_hex((char *) buffer + ref_length, actual_sha1)) {
|
|
free(buffer);
|
|
return NULL;
|
|
}
|
|
free(buffer);
|
|
/* Now we have the ID of the referred-to object in
|
|
* actual_sha1. Check again. */
|
|
}
|
|
}
|
|
|
|
static void write_sha1_file_prepare(void *buf, unsigned long len,
|
|
const char *type, unsigned char *sha1,
|
|
unsigned char *hdr, int *hdrlen)
|
|
{
|
|
SHA_CTX c;
|
|
|
|
/* Generate the header */
|
|
*hdrlen = sprintf((char *)hdr, "%s %lu", type, len)+1;
|
|
|
|
/* Sha1.. */
|
|
SHA1_Init(&c);
|
|
SHA1_Update(&c, hdr, *hdrlen);
|
|
SHA1_Update(&c, buf, len);
|
|
SHA1_Final(sha1, &c);
|
|
}
|
|
|
|
/*
|
|
* Link the tempfile to the final place, possibly creating the
|
|
* last directory level as you do so.
|
|
*
|
|
* Returns the errno on failure, 0 on success.
|
|
*/
|
|
static int link_temp_to_file(const char *tmpfile, const char *filename)
|
|
{
|
|
int ret;
|
|
char *dir;
|
|
|
|
if (!link(tmpfile, filename))
|
|
return 0;
|
|
|
|
/*
|
|
* Try to mkdir the last path component if that failed.
|
|
*
|
|
* Re-try the "link()" regardless of whether the mkdir
|
|
* succeeds, since a race might mean that somebody
|
|
* else succeeded.
|
|
*/
|
|
ret = errno;
|
|
dir = strrchr(filename, '/');
|
|
if (dir) {
|
|
*dir = 0;
|
|
if (!mkdir(filename, 0777) && adjust_shared_perm(filename)) {
|
|
*dir = '/';
|
|
return -2;
|
|
}
|
|
*dir = '/';
|
|
if (!link(tmpfile, filename))
|
|
return 0;
|
|
ret = errno;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Move the just written object into its final resting place
|
|
*/
|
|
int move_temp_to_file(const char *tmpfile, const char *filename)
|
|
{
|
|
int ret = link_temp_to_file(tmpfile, filename);
|
|
|
|
/*
|
|
* 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.
|
|
*
|
|
* The same holds for FAT formatted media.
|
|
*
|
|
* When this succeeds, we just return 0. We have nothing
|
|
* left to unlink.
|
|
*/
|
|
if (ret && ret != EEXIST) {
|
|
if (!rename(tmpfile, filename))
|
|
return 0;
|
|
ret = errno;
|
|
}
|
|
unlink(tmpfile);
|
|
if (ret) {
|
|
if (ret != EEXIST) {
|
|
return error("unable to write sha1 filename %s: %s\n", filename, strerror(ret));
|
|
}
|
|
/* FIXME!!! Collision check here ? */
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int write_buffer(int fd, const void *buf, size_t len)
|
|
{
|
|
while (len) {
|
|
ssize_t size;
|
|
|
|
size = write(fd, buf, len);
|
|
if (!size)
|
|
return error("file write: disk full");
|
|
if (size < 0) {
|
|
if (errno == EINTR || errno == EAGAIN)
|
|
continue;
|
|
return error("file write error (%s)", strerror(errno));
|
|
}
|
|
len -= size;
|
|
buf = (char *) buf + size;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int write_binary_header(unsigned char *hdr, enum object_type type, unsigned long len)
|
|
{
|
|
int hdr_len;
|
|
unsigned char c;
|
|
|
|
c = (type << 4) | (len & 15);
|
|
len >>= 4;
|
|
hdr_len = 1;
|
|
while (len) {
|
|
*hdr++ = c | 0x80;
|
|
hdr_len++;
|
|
c = (len & 0x7f);
|
|
len >>= 7;
|
|
}
|
|
*hdr = c;
|
|
return hdr_len;
|
|
}
|
|
|
|
static void setup_object_header(z_stream *stream, const char *type, unsigned long len)
|
|
{
|
|
int obj_type, hdr;
|
|
|
|
if (use_legacy_headers) {
|
|
while (deflate(stream, 0) == Z_OK)
|
|
/* nothing */;
|
|
return;
|
|
}
|
|
if (!strcmp(type, blob_type))
|
|
obj_type = OBJ_BLOB;
|
|
else if (!strcmp(type, tree_type))
|
|
obj_type = OBJ_TREE;
|
|
else if (!strcmp(type, commit_type))
|
|
obj_type = OBJ_COMMIT;
|
|
else if (!strcmp(type, tag_type))
|
|
obj_type = OBJ_TAG;
|
|
else
|
|
die("trying to generate bogus object of type '%s'", type);
|
|
hdr = write_binary_header(stream->next_out, obj_type, len);
|
|
stream->total_out = hdr;
|
|
stream->next_out += hdr;
|
|
stream->avail_out -= hdr;
|
|
}
|
|
|
|
int hash_sha1_file(void *buf, unsigned long len, const char *type,
|
|
unsigned char *sha1)
|
|
{
|
|
unsigned char hdr[50];
|
|
int hdrlen;
|
|
write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
|
|
return 0;
|
|
}
|
|
|
|
int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *returnsha1)
|
|
{
|
|
int size;
|
|
unsigned char *compressed;
|
|
z_stream stream;
|
|
unsigned char sha1[20];
|
|
char *filename;
|
|
static char tmpfile[PATH_MAX];
|
|
unsigned char hdr[50];
|
|
int fd, hdrlen;
|
|
|
|
/* Normally if we have it in the pack then we do not bother writing
|
|
* it out into .git/objects/??/?{38} file.
|
|
*/
|
|
write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
|
|
filename = sha1_file_name(sha1);
|
|
if (returnsha1)
|
|
hashcpy(returnsha1, sha1);
|
|
if (has_sha1_file(sha1))
|
|
return 0;
|
|
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) {
|
|
return error("sha1 file %s: %s\n", filename, strerror(errno));
|
|
}
|
|
|
|
snprintf(tmpfile, sizeof(tmpfile), "%s/obj_XXXXXX", get_object_directory());
|
|
|
|
fd = mkstemp(tmpfile);
|
|
if (fd < 0) {
|
|
if (errno == EPERM)
|
|
return error("insufficient permission for adding an object to repository database %s\n", get_object_directory());
|
|
else
|
|
return error("unable to create temporary sha1 filename %s: %s\n", tmpfile, strerror(errno));
|
|
}
|
|
|
|
/* Set it up */
|
|
memset(&stream, 0, sizeof(stream));
|
|
deflateInit(&stream, zlib_compression_level);
|
|
size = 8 + 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;
|
|
setup_object_header(&stream, type, len);
|
|
|
|
/* 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_buffer(fd, compressed, size) < 0)
|
|
die("unable to write sha1 file");
|
|
fchmod(fd, 0444);
|
|
close(fd);
|
|
free(compressed);
|
|
|
|
return move_temp_to_file(tmpfile, filename);
|
|
}
|
|
|
|
/*
|
|
* We need to unpack and recompress the object for writing
|
|
* it out to a different file.
|
|
*/
|
|
static void *repack_object(const unsigned char *sha1, unsigned long *objsize)
|
|
{
|
|
size_t size;
|
|
z_stream stream;
|
|
unsigned char *unpacked;
|
|
unsigned long len;
|
|
char type[20];
|
|
char hdr[50];
|
|
int hdrlen;
|
|
void *buf;
|
|
|
|
/* need to unpack and recompress it by itself */
|
|
unpacked = read_packed_sha1(sha1, type, &len);
|
|
|
|
hdrlen = sprintf(hdr, "%s %lu", type, len) + 1;
|
|
|
|
/* Set it up */
|
|
memset(&stream, 0, sizeof(stream));
|
|
deflateInit(&stream, zlib_compression_level);
|
|
size = deflateBound(&stream, len + hdrlen);
|
|
buf = xmalloc(size);
|
|
|
|
/* Compress it */
|
|
stream.next_out = buf;
|
|
stream.avail_out = size;
|
|
|
|
/* First header.. */
|
|
stream.next_in = (void *)hdr;
|
|
stream.avail_in = hdrlen;
|
|
while (deflate(&stream, 0) == Z_OK)
|
|
/* nothing */;
|
|
|
|
/* Then the data itself.. */
|
|
stream.next_in = unpacked;
|
|
stream.avail_in = len;
|
|
while (deflate(&stream, Z_FINISH) == Z_OK)
|
|
/* nothing */;
|
|
deflateEnd(&stream);
|
|
free(unpacked);
|
|
|
|
*objsize = stream.total_out;
|
|
return buf;
|
|
}
|
|
|
|
int write_sha1_to_fd(int fd, const unsigned char *sha1)
|
|
{
|
|
int retval;
|
|
unsigned long objsize;
|
|
void *buf = map_sha1_file(sha1, &objsize);
|
|
|
|
if (buf) {
|
|
retval = write_buffer(fd, buf, objsize);
|
|
munmap(buf, objsize);
|
|
return retval;
|
|
}
|
|
|
|
buf = repack_object(sha1, &objsize);
|
|
retval = write_buffer(fd, buf, objsize);
|
|
free(buf);
|
|
return retval;
|
|
}
|
|
|
|
int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer,
|
|
size_t bufsize, size_t *bufposn)
|
|
{
|
|
char tmpfile[PATH_MAX];
|
|
int local;
|
|
z_stream stream;
|
|
unsigned char real_sha1[20];
|
|
unsigned char discard[4096];
|
|
int ret;
|
|
SHA_CTX c;
|
|
|
|
snprintf(tmpfile, sizeof(tmpfile), "%s/obj_XXXXXX", get_object_directory());
|
|
|
|
local = mkstemp(tmpfile);
|
|
if (local < 0) {
|
|
if (errno == EPERM)
|
|
return error("insufficient permission for adding an object to repository database %s\n", get_object_directory());
|
|
else
|
|
return error("unable to create temporary sha1 filename %s: %s\n", tmpfile, strerror(errno));
|
|
}
|
|
|
|
memset(&stream, 0, sizeof(stream));
|
|
|
|
inflateInit(&stream);
|
|
|
|
SHA1_Init(&c);
|
|
|
|
do {
|
|
ssize_t size;
|
|
if (*bufposn) {
|
|
stream.avail_in = *bufposn;
|
|
stream.next_in = (unsigned char *) buffer;
|
|
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);
|
|
if (write_buffer(local, buffer, *bufposn - stream.avail_in) < 0)
|
|
die("unable to write sha1 file");
|
|
memmove(buffer, buffer + *bufposn - stream.avail_in,
|
|
stream.avail_in);
|
|
*bufposn = stream.avail_in;
|
|
if (ret != Z_OK)
|
|
break;
|
|
}
|
|
size = read(fd, buffer + *bufposn, bufsize - *bufposn);
|
|
if (size <= 0) {
|
|
close(local);
|
|
unlink(tmpfile);
|
|
if (!size)
|
|
return error("Connection closed?");
|
|
perror("Reading from connection");
|
|
return -1;
|
|
}
|
|
*bufposn += size;
|
|
} while (1);
|
|
inflateEnd(&stream);
|
|
|
|
close(local);
|
|
SHA1_Final(real_sha1, &c);
|
|
if (ret != Z_STREAM_END) {
|
|
unlink(tmpfile);
|
|
return error("File %s corrupted", sha1_to_hex(sha1));
|
|
}
|
|
if (hashcmp(sha1, real_sha1)) {
|
|
unlink(tmpfile);
|
|
return error("File %s has bad hash", sha1_to_hex(sha1));
|
|
}
|
|
|
|
return move_temp_to_file(tmpfile, sha1_file_name(sha1));
|
|
}
|
|
|
|
int has_pack_index(const unsigned char *sha1)
|
|
{
|
|
struct stat st;
|
|
if (stat(sha1_pack_index_name(sha1), &st))
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
int has_pack_file(const unsigned char *sha1)
|
|
{
|
|
struct stat st;
|
|
if (stat(sha1_pack_name(sha1), &st))
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
int has_sha1_pack(const unsigned char *sha1, const char **ignore_packed)
|
|
{
|
|
struct pack_entry e;
|
|
return find_pack_entry(sha1, &e, ignore_packed);
|
|
}
|
|
|
|
int has_sha1_file(const unsigned char *sha1)
|
|
{
|
|
struct stat st;
|
|
struct pack_entry e;
|
|
|
|
if (find_pack_entry(sha1, &e, NULL))
|
|
return 1;
|
|
return find_sha1_file(sha1, &st) ? 1 : 0;
|
|
}
|
|
|
|
/*
|
|
* reads from fd as long as possible into a supplied buffer of size bytes.
|
|
* If necessary the buffer's size is increased using realloc()
|
|
*
|
|
* returns 0 if anything went fine and -1 otherwise
|
|
*
|
|
* NOTE: both buf and size may change, but even when -1 is returned
|
|
* you still have to free() it yourself.
|
|
*/
|
|
int read_pipe(int fd, char** return_buf, unsigned long* return_size)
|
|
{
|
|
char* buf = *return_buf;
|
|
unsigned long size = *return_size;
|
|
int iret;
|
|
unsigned long off = 0;
|
|
|
|
do {
|
|
iret = xread(fd, buf + off, size - off);
|
|
if (iret > 0) {
|
|
off += iret;
|
|
if (off == size) {
|
|
size *= 2;
|
|
buf = xrealloc(buf, size);
|
|
}
|
|
}
|
|
} while (iret > 0);
|
|
|
|
*return_buf = buf;
|
|
*return_size = off;
|
|
|
|
if (iret < 0)
|
|
return -1;
|
|
return 0;
|
|
}
|
|
|
|
int index_pipe(unsigned char *sha1, int fd, const char *type, int write_object)
|
|
{
|
|
unsigned long size = 4096;
|
|
char *buf = xmalloc(size);
|
|
int ret;
|
|
|
|
if (read_pipe(fd, &buf, &size)) {
|
|
free(buf);
|
|
return -1;
|
|
}
|
|
|
|
if (!type)
|
|
type = blob_type;
|
|
if (write_object)
|
|
ret = write_sha1_file(buf, size, type, sha1);
|
|
else
|
|
ret = hash_sha1_file(buf, size, type, sha1);
|
|
free(buf);
|
|
return ret;
|
|
}
|
|
|
|
int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, const char *type)
|
|
{
|
|
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 (buf == MAP_FAILED)
|
|
return -1;
|
|
|
|
if (!type)
|
|
type = blob_type;
|
|
if (write_object)
|
|
ret = write_sha1_file(buf, size, type, sha1);
|
|
else
|
|
ret = hash_sha1_file(buf, size, type, sha1);
|
|
if (size)
|
|
munmap(buf, size);
|
|
return ret;
|
|
}
|
|
|
|
int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object)
|
|
{
|
|
int fd;
|
|
char *target;
|
|
|
|
switch (st->st_mode & S_IFMT) {
|
|
case S_IFREG:
|
|
fd = open(path, O_RDONLY);
|
|
if (fd < 0)
|
|
return error("open(\"%s\"): %s", path,
|
|
strerror(errno));
|
|
if (index_fd(sha1, fd, st, write_object, NULL) < 0)
|
|
return error("%s: failed to insert into database",
|
|
path);
|
|
break;
|
|
case S_IFLNK:
|
|
target = xmalloc(st->st_size+1);
|
|
if (readlink(path, target, st->st_size+1) != st->st_size) {
|
|
char *errstr = strerror(errno);
|
|
free(target);
|
|
return error("readlink(\"%s\"): %s", path,
|
|
errstr);
|
|
}
|
|
if (!write_object)
|
|
hash_sha1_file(target, st->st_size, blob_type, sha1);
|
|
else if (write_sha1_file(target, st->st_size, blob_type, sha1))
|
|
return error("%s: failed to insert into database",
|
|
path);
|
|
free(target);
|
|
break;
|
|
default:
|
|
return error("%s: unsupported file type", path);
|
|
}
|
|
return 0;
|
|
}
|