From ff417260cf36a73b7cb39b40e6c81e5313e28b9b Mon Sep 17 00:00:00 2001 From: Jeff King Date: Mon, 28 May 2018 05:38:53 -0400 Subject: make show-index a builtin The git-show-index command is built as its own separate program. There's really no good reason for this, and it means we waste extra space on disk (and CPU time running the linker). Let's fold it in to the main binary as a builtin. The history here is actually a bit amusing. The program itself is mostly self-contained, and doesn't even use our normal pack index code. In a5031214c4 (slim down "git show-index", 2010-01-21), we even stopped using xmalloc() so that it could avoid libgit.a entirely. But then 040a655116 (cleanup: use internal memory allocation wrapper functions everywhere, 2011-10-06) switched that back to xmalloc, which later become ALLOC_ARRAY(). Making it a builtin should give us the best of both worlds: no wasted space and no need to avoid the usual patterns. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano diff --git a/Makefile b/Makefile index a1d8775..ebc1a57 100644 --- a/Makefile +++ b/Makefile @@ -642,7 +642,6 @@ PROGRAM_OBJS += http-backend.o PROGRAM_OBJS += imap-send.o PROGRAM_OBJS += sh-i18n--envsubst.o PROGRAM_OBJS += shell.o -PROGRAM_OBJS += show-index.o PROGRAM_OBJS += upload-pack.o PROGRAM_OBJS += remote-testsvn.o @@ -1019,6 +1018,7 @@ BUILTIN_OBJS += builtin/rm.o BUILTIN_OBJS += builtin/send-pack.o BUILTIN_OBJS += builtin/shortlog.o BUILTIN_OBJS += builtin/show-branch.o +BUILTIN_OBJS += builtin/show-index.o BUILTIN_OBJS += builtin/show-ref.o BUILTIN_OBJS += builtin/stripspace.o BUILTIN_OBJS += builtin/submodule--helper.o diff --git a/builtin.h b/builtin.h index 42378f3..feb559e 100644 --- a/builtin.h +++ b/builtin.h @@ -218,6 +218,7 @@ extern int cmd_send_pack(int argc, const char **argv, const char *prefix); extern int cmd_shortlog(int argc, const char **argv, const char *prefix); extern int cmd_show(int argc, const char **argv, const char *prefix); extern int cmd_show_branch(int argc, const char **argv, const char *prefix); +extern int cmd_show_index(int argc, const char **argv, const char *prefix); extern int cmd_status(int argc, const char **argv, const char *prefix); extern int cmd_stripspace(int argc, const char **argv, const char *prefix); extern int cmd_submodule__helper(int argc, const char **argv, const char *prefix); diff --git a/builtin/show-index.c b/builtin/show-index.c new file mode 100644 index 0000000..a6e6788 --- /dev/null +++ b/builtin/show-index.c @@ -0,0 +1,86 @@ +#include "builtin.h" +#include "cache.h" +#include "pack.h" + +static const char show_index_usage[] = +"git show-index"; + +int cmd_show_index(int argc, const char **argv, const char *prefix) +{ + int i; + unsigned nr; + unsigned int version; + static unsigned int top_index[256]; + + if (argc != 1) + usage(show_index_usage); + if (fread(top_index, 2 * 4, 1, stdin) != 1) + die("unable to read header"); + if (top_index[0] == htonl(PACK_IDX_SIGNATURE)) { + version = ntohl(top_index[1]); + if (version < 2 || version > 2) + die("unknown index version"); + if (fread(top_index, 256 * 4, 1, stdin) != 1) + die("unable to read index"); + } else { + version = 1; + if (fread(&top_index[2], 254 * 4, 1, stdin) != 1) + die("unable to read index"); + } + nr = 0; + for (i = 0; i < 256; i++) { + unsigned n = ntohl(top_index[i]); + if (n < nr) + die("corrupt index file"); + nr = n; + } + if (version == 1) { + for (i = 0; i < nr; i++) { + unsigned int offset, entry[6]; + + if (fread(entry, 4 + 20, 1, stdin) != 1) + die("unable to read entry %u/%u", i, nr); + offset = ntohl(entry[0]); + printf("%u %s\n", offset, sha1_to_hex((void *)(entry+1))); + } + } else { + unsigned off64_nr = 0; + struct { + unsigned char sha1[20]; + uint32_t crc; + uint32_t off; + } *entries; + ALLOC_ARRAY(entries, nr); + for (i = 0; i < nr; i++) + if (fread(entries[i].sha1, 20, 1, stdin) != 1) + die("unable to read sha1 %u/%u", i, nr); + for (i = 0; i < nr; i++) + if (fread(&entries[i].crc, 4, 1, stdin) != 1) + die("unable to read crc %u/%u", i, nr); + for (i = 0; i < nr; i++) + if (fread(&entries[i].off, 4, 1, stdin) != 1) + die("unable to read 32b offset %u/%u", i, nr); + for (i = 0; i < nr; i++) { + uint64_t offset; + uint32_t off = ntohl(entries[i].off); + if (!(off & 0x80000000)) { + offset = off; + } else { + uint32_t off64[2]; + if ((off & 0x7fffffff) != off64_nr) + die("inconsistent 64b offset index"); + if (fread(off64, 8, 1, stdin) != 1) + die("unable to read 64b offset %u", off64_nr); + offset = (((uint64_t)ntohl(off64[0])) << 32) | + ntohl(off64[1]); + off64_nr++; + } + printf("%" PRIuMAX " %s (%08"PRIx32")\n", + (uintmax_t) offset, + sha1_to_hex(entries[i].sha1), + ntohl(entries[i].crc)); + } + free(entries); + } + return 0; +} diff --git a/git.c b/git.c index ceaa58e..1a10c96 100644 --- a/git.c +++ b/git.c @@ -464,6 +464,7 @@ static struct cmd_struct commands[] = { { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER }, { "show", cmd_show, RUN_SETUP }, { "show-branch", cmd_show_branch, RUN_SETUP }, + { "show-index", cmd_show_index }, { "show-ref", cmd_show_ref, RUN_SETUP }, { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE }, { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE }, diff --git a/show-index.c b/show-index.c deleted file mode 100644 index 1ead41e..0000000 --- a/show-index.c +++ /dev/null @@ -1,85 +0,0 @@ -#include "cache.h" -#include "pack.h" - -static const char show_index_usage[] = -"git show-index"; - -int cmd_main(int argc, const char **argv) -{ - int i; - unsigned nr; - unsigned int version; - static unsigned int top_index[256]; - - if (argc != 1) - usage(show_index_usage); - if (fread(top_index, 2 * 4, 1, stdin) != 1) - die("unable to read header"); - if (top_index[0] == htonl(PACK_IDX_SIGNATURE)) { - version = ntohl(top_index[1]); - if (version < 2 || version > 2) - die("unknown index version"); - if (fread(top_index, 256 * 4, 1, stdin) != 1) - die("unable to read index"); - } else { - version = 1; - if (fread(&top_index[2], 254 * 4, 1, stdin) != 1) - die("unable to read index"); - } - nr = 0; - for (i = 0; i < 256; i++) { - unsigned n = ntohl(top_index[i]); - if (n < nr) - die("corrupt index file"); - nr = n; - } - if (version == 1) { - for (i = 0; i < nr; i++) { - unsigned int offset, entry[6]; - - if (fread(entry, 4 + 20, 1, stdin) != 1) - die("unable to read entry %u/%u", i, nr); - offset = ntohl(entry[0]); - printf("%u %s\n", offset, sha1_to_hex((void *)(entry+1))); - } - } else { - unsigned off64_nr = 0; - struct { - unsigned char sha1[20]; - uint32_t crc; - uint32_t off; - } *entries; - ALLOC_ARRAY(entries, nr); - for (i = 0; i < nr; i++) - if (fread(entries[i].sha1, 20, 1, stdin) != 1) - die("unable to read sha1 %u/%u", i, nr); - for (i = 0; i < nr; i++) - if (fread(&entries[i].crc, 4, 1, stdin) != 1) - die("unable to read crc %u/%u", i, nr); - for (i = 0; i < nr; i++) - if (fread(&entries[i].off, 4, 1, stdin) != 1) - die("unable to read 32b offset %u/%u", i, nr); - for (i = 0; i < nr; i++) { - uint64_t offset; - uint32_t off = ntohl(entries[i].off); - if (!(off & 0x80000000)) { - offset = off; - } else { - uint32_t off64[2]; - if ((off & 0x7fffffff) != off64_nr) - die("inconsistent 64b offset index"); - if (fread(off64, 8, 1, stdin) != 1) - die("unable to read 64b offset %u", off64_nr); - offset = (((uint64_t)ntohl(off64[0])) << 32) | - ntohl(off64[1]); - off64_nr++; - } - printf("%" PRIuMAX " %s (%08"PRIx32")\n", - (uintmax_t) offset, - sha1_to_hex(entries[i].sha1), - ntohl(entries[i].crc)); - } - free(entries); - } - return 0; -} -- cgit v0.10.2-6-g49f6 From fb3010c31fdaa00ae91152431c3da7e300daf848 Mon Sep 17 00:00:00 2001 From: Jeff King Date: Mon, 28 May 2018 05:39:23 -0400 Subject: show-index: update documentation for index v2 Commit 32637cdf4a (show-index.c: learn about index v2, 2007-04-09) changed the output format of show-index to include the object CRC32 but didn't update the documentation. Let's fix that and generally describe the output in more detail. There are a few other fixes here while we're rewording: - refer to index-pack along with pack-objects, since either can create .idx files - use "linkgit:" for referring to other commands - expand the bit about verify-pack, giving reasons why you might want this command instead. I almost omitted this entirely, but referring to verify-pack might help a reader who is looking for more information. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano diff --git a/Documentation/git-show-index.txt b/Documentation/git-show-index.txt index a8a9509..424e4ba 100644 --- a/Documentation/git-show-index.txt +++ b/Documentation/git-show-index.txt @@ -14,13 +14,27 @@ SYNOPSIS DESCRIPTION ----------- -Read the idx file for a Git packfile created with -'git pack-objects' command from the standard input, and -dump its contents. +Read the `.idx` file for a Git packfile (created with +linkgit:git-pack-objects[1] or linkgit:git-index-pack[1]) from the +standard input, and dump its contents. The output consists of one object +per line, with each line containing two or three space-separated +columns: -The information it outputs is subset of what you can get from -'git verify-pack -v'; this command only shows the packfile -offset and SHA-1 of each object. + - the first column is the offset in bytes of the object within the + corresponding packfile + + - the second column is the object id of the object + + - if the index version is 2 or higher, the third column contains the + CRC32 of the object data + +The objects are output in the order in which they are found in the index +file, which should be (in a correctly constructed file) sorted by object +id. + +Note that you can get more information on a packfile by calling +linkgit:git-verify-pack[1]. However, as this command considers only the +index file itself, it's both faster and more flexible. GIT --- -- cgit v0.10.2-6-g49f6