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authorJunio C Hamano <gitster@pobox.com>2011-11-23 13:28:53 -0800
committerJunio C Hamano <gitster@pobox.com>2011-11-23 13:28:53 -0800
commit3686aa1caf907d22fe318c28efe93f0e7870ba50 (patch)
treef99a303bd14c7343be7ccc5b9df5382f1bf79246 /index-pack.c
parentaa2577a9c3bd5559bd580feca6edec4d70254adc (diff)
parent1e501a7c47ad5ada53d3b1acfb9f131f76e969ec (diff)
downloadgit-tj/maint-imap-send-remove-unused.tar.gz
Merge branch 'maint' into tj/imap-send-remove-unusedtj/maint-imap-send-remove-unused
* maint: (18123 commits) documentation fix: git difftool uses diff tools, not merge tools. Git 1.7.7.4 Makefile: add missing header file dependencies notes merge: eliminate OUTPUT macro mailmap: xcalloc mailmap_info name-rev --all: do not even attempt to describe non-commit object Git 1.7.7.3 docs: Update install-doc-quick docs: don't mention --quiet or --exit-code in git-log(1) Git 1.7.7.2 t7511: avoid use of reserved filename on Windows. clone: Quote user supplied path in a single quote pair read-cache.c: fix index memory allocation make the sample pre-commit hook script reject names with newlines, too Reindent closing bracket using tab instead of spaces Git 1.7.7.1 RelNotes/1.7.7.1: setgid bit patch is about fixing "git init" via Makefile setting gitweb: fix regression when filtering out forks Almost ready for 1.7.7.1 pack-objects: don't traverse objects unnecessarily ... Conflicts: imap-send.c
Diffstat (limited to 'index-pack.c')
-rw-r--r--index-pack.c468
1 files changed, 0 insertions, 468 deletions
diff --git a/index-pack.c b/index-pack.c
deleted file mode 100644
index babe34b2db..0000000000
--- a/index-pack.c
+++ /dev/null
@@ -1,468 +0,0 @@
-#include "cache.h"
-#include "delta.h"
-#include "pack.h"
-#include "csum-file.h"
-
-static const char index_pack_usage[] =
-"git-index-pack [-o index-file] pack-file";
-
-struct object_entry
-{
- unsigned long offset;
- enum object_type type;
- enum object_type real_type;
- unsigned char sha1[20];
-};
-
-struct delta_entry
-{
- struct object_entry *obj;
- unsigned char base_sha1[20];
-};
-
-static const char *pack_name;
-static unsigned char *pack_base;
-static unsigned long pack_size;
-static struct object_entry *objects;
-static struct delta_entry *deltas;
-static int nr_objects;
-static int nr_deltas;
-
-static void open_pack_file(void)
-{
- int fd;
- struct stat st;
-
- fd = open(pack_name, O_RDONLY);
- if (fd < 0)
- die("cannot open packfile '%s': %s", pack_name,
- strerror(errno));
- if (fstat(fd, &st)) {
- int err = errno;
- close(fd);
- die("cannot fstat packfile '%s': %s", pack_name,
- strerror(err));
- }
- pack_size = st.st_size;
- pack_base = mmap(NULL, pack_size, PROT_READ, MAP_PRIVATE, fd, 0);
- if (pack_base == MAP_FAILED) {
- int err = errno;
- close(fd);
- die("cannot mmap packfile '%s': %s", pack_name,
- strerror(err));
- }
- close(fd);
-}
-
-static void parse_pack_header(void)
-{
- const struct pack_header *hdr;
- unsigned char sha1[20];
- SHA_CTX ctx;
-
- /* Ensure there are enough bytes for the header and final SHA1 */
- if (pack_size < sizeof(struct pack_header) + 20)
- die("packfile '%s' is too small", pack_name);
-
- /* Header consistency check */
- hdr = (void *)pack_base;
- if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
- die("packfile '%s' signature mismatch", pack_name);
- if (!pack_version_ok(hdr->hdr_version))
- die("packfile '%s' version %d unsupported",
- pack_name, ntohl(hdr->hdr_version));
-
- nr_objects = ntohl(hdr->hdr_entries);
-
- /* Check packfile integrity */
- SHA1_Init(&ctx);
- SHA1_Update(&ctx, pack_base, pack_size - 20);
- SHA1_Final(sha1, &ctx);
- if (memcmp(sha1, pack_base + pack_size - 20, 20))
- die("packfile '%s' SHA1 mismatch", pack_name);
-}
-
-static void bad_object(unsigned long offset, const char *format,
- ...) NORETURN __attribute__((format (printf, 2, 3)));
-
-static void bad_object(unsigned long offset, const char *format, ...)
-{
- va_list params;
- char buf[1024];
-
- va_start(params, format);
- vsnprintf(buf, sizeof(buf), format, params);
- va_end(params);
- die("packfile '%s': bad object at offset %lu: %s",
- pack_name, offset, buf);
-}
-
-static void *unpack_entry_data(unsigned long offset,
- unsigned long *current_pos, unsigned long size)
-{
- unsigned long pack_limit = pack_size - 20;
- unsigned long pos = *current_pos;
- z_stream stream;
- void *buf = xmalloc(size);
-
- memset(&stream, 0, sizeof(stream));
- stream.next_out = buf;
- stream.avail_out = size;
- stream.next_in = pack_base + pos;
- stream.avail_in = pack_limit - pos;
- inflateInit(&stream);
-
- for (;;) {
- int ret = inflate(&stream, 0);
- if (ret == Z_STREAM_END)
- break;
- if (ret != Z_OK)
- bad_object(offset, "inflate returned %d", ret);
- }
- inflateEnd(&stream);
- if (stream.total_out != size)
- bad_object(offset, "size mismatch (expected %lu, got %lu)",
- size, stream.total_out);
- *current_pos = pack_limit - stream.avail_in;
- return buf;
-}
-
-static void *unpack_raw_entry(unsigned long offset,
- enum object_type *obj_type,
- unsigned long *obj_size,
- unsigned char *delta_base,
- unsigned long *next_obj_offset)
-{
- unsigned long pack_limit = pack_size - 20;
- unsigned long pos = offset;
- unsigned char c;
- unsigned long size;
- unsigned shift;
- enum object_type type;
- void *data;
-
- c = pack_base[pos++];
- type = (c >> 4) & 7;
- size = (c & 15);
- shift = 4;
- while (c & 0x80) {
- if (pos >= pack_limit)
- bad_object(offset, "object extends past end of pack");
- c = pack_base[pos++];
- size += (c & 0x7fUL) << shift;
- shift += 7;
- }
-
- switch (type) {
- case OBJ_DELTA:
- if (pos + 20 >= pack_limit)
- bad_object(offset, "object extends past end of pack");
- memcpy(delta_base, pack_base + pos, 20);
- pos += 20;
- /* fallthru */
- case OBJ_COMMIT:
- case OBJ_TREE:
- case OBJ_BLOB:
- case OBJ_TAG:
- data = unpack_entry_data(offset, &pos, size);
- break;
- default:
- bad_object(offset, "bad object type %d", type);
- }
-
- *obj_type = type;
- *obj_size = size;
- *next_obj_offset = pos;
- return data;
-}
-
-static int find_delta(const unsigned char *base_sha1)
-{
- int first = 0, last = nr_deltas;
-
- while (first < last) {
- int next = (first + last) / 2;
- struct delta_entry *delta = &deltas[next];
- int cmp;
-
- cmp = memcmp(base_sha1, delta->base_sha1, 20);
- if (!cmp)
- return next;
- if (cmp < 0) {
- last = next;
- continue;
- }
- first = next+1;
- }
- return -first-1;
-}
-
-static int find_deltas_based_on_sha1(const unsigned char *base_sha1,
- int *first_index, int *last_index)
-{
- int first = find_delta(base_sha1);
- int last = first;
- int end = nr_deltas - 1;
-
- if (first < 0)
- return -1;
- while (first > 0 && !memcmp(deltas[first-1].base_sha1, base_sha1, 20))
- --first;
- while (last < end && !memcmp(deltas[last+1].base_sha1, base_sha1, 20))
- ++last;
- *first_index = first;
- *last_index = last;
- return 0;
-}
-
-static void sha1_object(const void *data, unsigned long size,
- enum object_type type, unsigned char *sha1)
-{
- SHA_CTX ctx;
- char header[50];
- int header_size;
- const char *type_str;
-
- switch (type) {
- case OBJ_COMMIT: type_str = "commit"; break;
- case OBJ_TREE: type_str = "tree"; break;
- case OBJ_BLOB: type_str = "blob"; break;
- case OBJ_TAG: type_str = "tag"; break;
- default:
- die("bad type %d", type);
- }
-
- header_size = sprintf(header, "%s %lu", type_str, size) + 1;
-
- SHA1_Init(&ctx);
- SHA1_Update(&ctx, header, header_size);
- SHA1_Update(&ctx, data, size);
- SHA1_Final(sha1, &ctx);
-}
-
-static void resolve_delta(struct delta_entry *delta, void *base_data,
- unsigned long base_size, enum object_type type)
-{
- struct object_entry *obj = delta->obj;
- void *delta_data;
- unsigned long delta_size;
- void *result;
- unsigned long result_size;
- enum object_type delta_type;
- unsigned char base_sha1[20];
- unsigned long next_obj_offset;
- int j, first, last;
-
- obj->real_type = type;
- delta_data = unpack_raw_entry(obj->offset, &delta_type,
- &delta_size, base_sha1,
- &next_obj_offset);
- result = patch_delta(base_data, base_size, delta_data, delta_size,
- &result_size);
- free(delta_data);
- if (!result)
- bad_object(obj->offset, "failed to apply delta");
- sha1_object(result, result_size, type, obj->sha1);
- if (!find_deltas_based_on_sha1(obj->sha1, &first, &last)) {
- for (j = first; j <= last; j++)
- resolve_delta(&deltas[j], result, result_size, type);
- }
- free(result);
-}
-
-static int compare_delta_entry(const void *a, const void *b)
-{
- const struct delta_entry *delta_a = a;
- const struct delta_entry *delta_b = b;
- return memcmp(delta_a->base_sha1, delta_b->base_sha1, 20);
-}
-
-static void parse_pack_objects(void)
-{
- int i;
- unsigned long offset = sizeof(struct pack_header);
- unsigned char base_sha1[20];
- void *data;
- unsigned long data_size;
-
- /*
- * First pass:
- * - find locations of all objects;
- * - calculate SHA1 of all non-delta objects;
- * - remember base SHA1 for all deltas.
- */
- for (i = 0; i < nr_objects; i++) {
- struct object_entry *obj = &objects[i];
- obj->offset = offset;
- data = unpack_raw_entry(offset, &obj->type, &data_size,
- base_sha1, &offset);
- obj->real_type = obj->type;
- if (obj->type == OBJ_DELTA) {
- struct delta_entry *delta = &deltas[nr_deltas++];
- delta->obj = obj;
- memcpy(delta->base_sha1, base_sha1, 20);
- } else
- sha1_object(data, data_size, obj->type, obj->sha1);
- free(data);
- }
- if (offset != pack_size - 20)
- die("packfile '%s' has junk at the end", pack_name);
-
- /* Sort deltas by base SHA1 for fast searching */
- qsort(deltas, nr_deltas, sizeof(struct delta_entry),
- compare_delta_entry);
-
- /*
- * Second pass:
- * - for all non-delta objects, look if it is used as a base for
- * deltas;
- * - if used as a base, uncompress the object and apply all deltas,
- * recursively checking if the resulting object is used as a base
- * for some more deltas.
- */
- for (i = 0; i < nr_objects; i++) {
- struct object_entry *obj = &objects[i];
- int j, first, last;
-
- if (obj->type == OBJ_DELTA)
- continue;
- if (find_deltas_based_on_sha1(obj->sha1, &first, &last))
- continue;
- data = unpack_raw_entry(obj->offset, &obj->type, &data_size,
- base_sha1, &offset);
- for (j = first; j <= last; j++)
- resolve_delta(&deltas[j], data, data_size, obj->type);
- free(data);
- }
-
- /* Check for unresolved deltas */
- for (i = 0; i < nr_deltas; i++) {
- if (deltas[i].obj->real_type == OBJ_DELTA)
- die("packfile '%s' has unresolved deltas", pack_name);
- }
-}
-
-static int sha1_compare(const void *_a, const void *_b)
-{
- struct object_entry *a = *(struct object_entry **)_a;
- struct object_entry *b = *(struct object_entry **)_b;
- return memcmp(a->sha1, b->sha1, 20);
-}
-
-static void write_index_file(const char *index_name, unsigned char *sha1)
-{
- struct sha1file *f;
- struct object_entry **sorted_by_sha, **list, **last;
- unsigned int array[256];
- int i;
- SHA_CTX ctx;
-
- if (nr_objects) {
- sorted_by_sha =
- xcalloc(nr_objects, sizeof(struct object_entry *));
- list = sorted_by_sha;
- last = sorted_by_sha + nr_objects;
- for (i = 0; i < nr_objects; ++i)
- sorted_by_sha[i] = &objects[i];
- qsort(sorted_by_sha, nr_objects, sizeof(sorted_by_sha[0]),
- sha1_compare);
-
- }
- else
- sorted_by_sha = list = last = NULL;
-
- unlink(index_name);
- f = sha1create("%s", index_name);
-
- /*
- * Write the first-level table (the list is sorted,
- * but we use a 256-entry lookup to be able to avoid
- * having to do eight extra binary search iterations).
- */
- for (i = 0; i < 256; i++) {
- struct object_entry **next = list;
- while (next < last) {
- struct object_entry *obj = *next;
- if (obj->sha1[0] != i)
- break;
- next++;
- }
- array[i] = htonl(next - sorted_by_sha);
- list = next;
- }
- sha1write(f, array, 256 * sizeof(int));
-
- /* recompute the SHA1 hash of sorted object names.
- * currently pack-objects does not do this, but that
- * can be fixed.
- */
- SHA1_Init(&ctx);
- /*
- * Write the actual SHA1 entries..
- */
- list = sorted_by_sha;
- for (i = 0; i < nr_objects; i++) {
- struct object_entry *obj = *list++;
- unsigned int offset = htonl(obj->offset);
- sha1write(f, &offset, 4);
- sha1write(f, obj->sha1, 20);
- SHA1_Update(&ctx, obj->sha1, 20);
- }
- sha1write(f, pack_base + pack_size - 20, 20);
- sha1close(f, NULL, 1);
- free(sorted_by_sha);
- SHA1_Final(sha1, &ctx);
-}
-
-int main(int argc, char **argv)
-{
- int i;
- char *index_name = NULL;
- char *index_name_buf = NULL;
- unsigned char sha1[20];
-
- for (i = 1; i < argc; i++) {
- const char *arg = argv[i];
-
- if (*arg == '-') {
- if (!strcmp(arg, "-o")) {
- if (index_name || (i+1) >= argc)
- usage(index_pack_usage);
- index_name = argv[++i];
- } else
- usage(index_pack_usage);
- continue;
- }
-
- if (pack_name)
- usage(index_pack_usage);
- pack_name = arg;
- }
-
- if (!pack_name)
- usage(index_pack_usage);
- if (!index_name) {
- int len = strlen(pack_name);
- if (len < 5 || strcmp(pack_name + len - 5, ".pack"))
- die("packfile name '%s' does not end with '.pack'",
- pack_name);
- index_name_buf = xmalloc(len);
- memcpy(index_name_buf, pack_name, len - 5);
- strcpy(index_name_buf + len - 5, ".idx");
- index_name = index_name_buf;
- }
-
- open_pack_file();
- parse_pack_header();
- objects = xcalloc(nr_objects, sizeof(struct object_entry));
- deltas = xcalloc(nr_objects, sizeof(struct delta_entry));
- parse_pack_objects();
- free(deltas);
- write_index_file(index_name, sha1);
- free(objects);
- free(index_name_buf);
-
- printf("%s\n", sha1_to_hex(sha1));
-
- return 0;
-}