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1877 lines
44 KiB
1877 lines
44 KiB
/* |
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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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|
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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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|
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const unsigned char null_sha1[20]; |
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|
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static unsigned int sha1_file_open_flag = O_NOATIME; |
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|
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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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|
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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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|
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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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|
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if (*pos == '/') |
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pos++; |
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|
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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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|
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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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|
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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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|
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return buffer; |
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} |
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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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/* |
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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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|
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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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|
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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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|
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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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|
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buf = name; |
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|
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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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|
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return base; |
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} |
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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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|
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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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|
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buf = name; |
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|
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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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|
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return base; |
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} |
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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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|
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static void read_info_alternates(const char * alternates, int depth); |
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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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/* recursively add alternates */ |
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read_info_alternates(ent->base, depth + 1); |
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|
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ent->base[pfxlen] = '/'; |
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|
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return 0; |
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} |
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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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|
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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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|
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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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|
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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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|
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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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|
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link_alt_odb_entries(map, map + st.st_size, '\n', relative_base, depth); |
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|
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munmap(map, st.st_size); |
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} |
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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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|
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alt = getenv(ALTERNATE_DB_ENVIRONMENT); |
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if (!alt) alt = ""; |
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|
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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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|
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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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|
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#define PACK_MAX_SZ (1<<26) |
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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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|
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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"); |
|
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"); |
|
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) |
|
* - 20-byte SHA1 of the packfile |
|
* - 20-byte SHA1 file checksum |
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*/ |
|
if (idx_size != 4*256 + nr * 24 + 20 + 20) |
|
return error("wrong index file size"); |
|
|
|
return 0; |
|
} |
|
|
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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; |
|
struct pack_header *hdr; |
|
|
|
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 we understand this pack file. If we don't we're |
|
* likely too old to handle it. |
|
*/ |
|
hdr = map; |
|
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, |
|
(unsigned char *)p->pack_base + |
|
p->pack_size - 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)) |
|
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->pack_base = NULL; |
|
p->pack_last_used = 0; |
|
p->pack_use_cnt = 0; |
|
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; |
|
} |
|
|
|
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) |
|
{ |
|
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 = (unsigned char *) p->pack_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 = (unsigned char *) p->pack_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((unsigned char *)p->pack_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("corrupted pack file %s containing object of kind %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 = (unsigned char *) p->pack_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("corrupted pack file %s containing object of kind %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 = (unsigned char*)p->pack_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_gently(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; |
|
} |
|
|
|
static void *unpack_entry(struct pack_entry *entry, |
|
char *type, unsigned long *sizep) |
|
{ |
|
struct packed_git *p = entry->p; |
|
void *retval; |
|
|
|
if (use_packed_git(p)) |
|
die("cannot map packed file"); |
|
retval = unpack_entry_gently(p, entry->offset, type, sizep); |
|
unuse_packed_git(p); |
|
if (!retval) |
|
die("corrupted pack file %s", p->pack_name); |
|
return retval; |
|
} |
|
|
|
/* The caller is responsible for use_packed_git()/unuse_packed_git() pair */ |
|
void *unpack_entry_gently(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 unpack_delta_entry(p, offset, size, kind, obj_offset, type, sizep); |
|
case OBJ_COMMIT: |
|
case OBJ_TREE: |
|
case OBJ_BLOB: |
|
case OBJ_TAG: |
|
strcpy(type, type_names[kind]); |
|
*sizep = size; |
|
return unpack_compressed_entry(p, offset, size); |
|
default: |
|
return NULL; |
|
} |
|
} |
|
|
|
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 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 (!strcmp(p->pack_name, *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; |
|
|
|
} |
|
|
|
int sha1_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) { |
|
struct pack_entry e; |
|
|
|
if (!find_pack_entry(sha1, &e, NULL)) { |
|
reprepare_packed_git(); |
|
if (!find_pack_entry(sha1, &e, NULL)) |
|
return error("unable to find %s", sha1_to_hex(sha1)); |
|
} |
|
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; |
|
} |
|
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; |
|
} |
|
|
|
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, 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; |
|
mkdir(filename, 0777); |
|
if (adjust_shared_perm(filename)) |
|
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) { |
|
fprintf(stderr, "unable to write sha1 filename %s: %s\n", filename, strerror(ret)); |
|
return -1; |
|
} |
|
/* 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) { |
|
fprintf(stderr, "sha1 file %s: %s\n", 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\n", tmpfile, strerror(errno)); |
|
return -1; |
|
} |
|
|
|
/* 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) |
|
return error("Couldn't open %s for %s", |
|
tmpfile, sha1_to_hex(sha1)); |
|
|
|
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; |
|
}
|
|
|