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[PATCH v3 04/10] builtin/index-pack.c: write reverse indexes

From
Taylor Blau <me@ttaylorr.com>
Date
Jan 25, 2021, 23:37 UTC
Message-ID
<a8ee59fccf678bd1bf57930cd6395f36273f74d6.1611617820.git.me@ttaylorr.com>
In-Reply-To
<cover.1611617819.git.me@ttaylorr.com>

Teach 'git index-pack' to optionally write and verify reverse index with '--[no-]rev-index', as well as respecting the 'pack.writeReverseIndex' configuration option.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
---
 Documentation/git-index-pack.txt | 18 +++++---
 builtin/index-pack.c             | 50 ++++++++++++++++++++--
 t/t5325-reverse-index.sh         | 71 ++++++++++++++++++++++++++++++++
 3 files changed, 131 insertions(+), 8 deletions(-)
 create mode 100755 t/t5325-reverse-index.sh
diff --git a/Documentation/git-index-pack.txt b/Documentation/git-index-pack.txt
index af0c26232c..69ba904d44 100644
--- a/Documentation/git-index-pack.txt
+++ b/Documentation/git-index-pack.txt
@@ -9,17 +9,18 @@ git-index-pack - Build pack index file for an existing packed archive
 SYNOPSIS
 --------
 [verse]
-'git index-pack' [-v] [-o <index-file>] <pack-file>
+'git index-pack' [-v] [-o <index-file>] [--[no-]rev-index] <pack-file>
 'git index-pack' --stdin [--fix-thin] [--keep] [-v] [-o <index-file>]
-                 [<pack-file>]
+		  [--[no-]rev-index] [<pack-file>]
 
 
 DESCRIPTION
 -----------
 Reads a packed archive (.pack) from the specified file, and
-builds a pack index file (.idx) for it.  The packed archive
-together with the pack index can then be placed in the
-objects/pack/ directory of a Git repository.
+builds a pack index file (.idx) for it. Optionally writes a
+reverse-index (.rev) for the specified pack. The packed
+archive together with the pack index can then be placed in
+the objects/pack/ directory of a Git repository.
 
 
 OPTIONS
@@ -35,6 +36,13 @@ OPTIONS
 	fails if the name of packed archive does not end
 	with .pack).
 
+--[no-]rev-index::
+	When this flag is provided, generate a reverse index
+	(a `.rev` file) corresponding to the given pack. If
+	`--verify` is given, ensure that the existing
+	reverse index is correct. Takes precedence over
+	`pack.writeReverseIndex`.
+
 --stdin::
 	When this flag is provided, the pack is read from stdin
 	instead and a copy is then written to <pack-file>. If
diff --git a/builtin/index-pack.c b/builtin/index-pack.c
index c758f3b8e9..d5cd665b98 100644
--- a/builtin/index-pack.c
+++ b/builtin/index-pack.c
@@ -17,7 +17,7 @@
 #include "promisor-remote.h"
 
 static const char index_pack_usage[] =
-"git index-pack [-v] [-o <index-file>] [--keep | --keep=<msg>] [--verify] [--strict] (<pack-file> | --stdin [--fix-thin] [<pack-file>])";
+"git index-pack [-v] [-o <index-file>] [--keep | --keep=<msg>] [--[no-]rev-index] [--verify] [--strict] (<pack-file> | --stdin [--fix-thin] [<pack-file>])";
 
 struct object_entry {
 	struct pack_idx_entry idx;
@@ -1484,12 +1484,14 @@ static void write_special_file(const char *suffix, const char *msg,
 
 static void final(const char *final_pack_name, const char *curr_pack_name,
 		  const char *final_index_name, const char *curr_index_name,
+		  const char *final_rev_index_name, const char *curr_rev_index_name,
 		  const char *keep_msg, const char *promisor_msg,
 		  unsigned char *hash)
 {
 	const char *report = "pack";
 	struct strbuf pack_name = STRBUF_INIT;
 	struct strbuf index_name = STRBUF_INIT;
+	struct strbuf rev_index_name = STRBUF_INIT;
 	int err;
 
 	if (!from_stdin) {
@@ -1524,6 +1526,16 @@ static void final(const char *final_pack_name, const char *curr_pack_name,
 	} else
 		chmod(final_index_name, 0444);
 
+	if (curr_rev_index_name) {
+		if (final_rev_index_name != curr_rev_index_name) {
+			if (!final_rev_index_name)
+				final_rev_index_name = odb_pack_name(&rev_index_name, hash, "rev");
+			if (finalize_object_file(curr_rev_index_name, final_rev_index_name))
+				die(_("cannot store reverse index file"));
+		} else
+			chmod(final_rev_index_name, 0444);
+	}
+
 	if (do_fsck_object) {
 		struct packed_git *p;
 		p = add_packed_git(final_index_name, strlen(final_index_name), 0);
@@ -1553,6 +1565,7 @@ static void final(const char *final_pack_name, const char *curr_pack_name,
 		}
 	}
 
+	strbuf_release(&rev_index_name);
 	strbuf_release(&index_name);
 	strbuf_release(&pack_name);
 }
@@ -1578,6 +1591,12 @@ static int git_index_pack_config(const char *k, const char *v, void *cb)
 		}
 		return 0;
 	}
+	if (!strcmp(k, "pack.writereverseindex")) {
+		if (git_config_bool(k, v))
+			opts->flags |= WRITE_REV;
+		else
+			opts->flags &= ~WRITE_REV;
+	}
 	return git_default_config(k, v, cb);
 }
 
@@ -1695,12 +1714,14 @@ static void show_pack_info(int stat_only)
 
 int cmd_index_pack(int argc, const char **argv, const char *prefix)
 {
-	int i, fix_thin_pack = 0, verify = 0, stat_only = 0;
+	int i, fix_thin_pack = 0, verify = 0, stat_only = 0, rev_index;
 	const char *curr_index;
-	const char *index_name = NULL, *pack_name = NULL;
+	const char *curr_rev_index = NULL;
+	const char *index_name = NULL, *pack_name = NULL, *rev_index_name = NULL;
 	const char *keep_msg = NULL;
 	const char *promisor_msg = NULL;
 	struct strbuf index_name_buf = STRBUF_INIT;
+	struct strbuf rev_index_name_buf = STRBUF_INIT;
 	struct pack_idx_entry **idx_objects;
 	struct pack_idx_option opts;
 	unsigned char pack_hash[GIT_MAX_RAWSZ];
@@ -1727,6 +1748,8 @@ int cmd_index_pack(int argc, const char **argv, const char *prefix)
 	if (prefix && chdir(prefix))
 		die(_("Cannot come back to cwd"));
 
+	rev_index = !!(opts.flags & (WRITE_REV_VERIFY | WRITE_REV));
+
 	for (i = 1; i < argc; i++) {
 		const char *arg = argv[i];
 
@@ -1805,6 +1828,10 @@ int cmd_index_pack(int argc, const char **argv, const char *prefix)
 				if (hash_algo == GIT_HASH_UNKNOWN)
 					die(_("unknown hash algorithm '%s'"), arg);
 				repo_set_hash_algo(the_repository, hash_algo);
+			} else if (!strcmp(arg, "--rev-index")) {
+				rev_index = 1;
+			} else if (!strcmp(arg, "--no-rev-index")) {
+				rev_index = 0;
 			} else
 				usage(index_pack_usage);
 			continue;
@@ -1826,6 +1853,15 @@ int cmd_index_pack(int argc, const char **argv, const char *prefix)
 	if (!index_name && pack_name)
 		index_name = derive_filename(pack_name, "pack", "idx", &index_name_buf);
 
+	opts.flags &= ~(WRITE_REV | WRITE_REV_VERIFY);
+	if (rev_index) {
+		opts.flags |= verify ? WRITE_REV_VERIFY : WRITE_REV;
+		if (index_name)
+			rev_index_name = derive_filename(index_name,
+							 "idx", "rev",
+							 &rev_index_name_buf);
+	}
+
 	if (verify) {
 		if (!index_name)
 			die(_("--verify with no packfile name given"));
@@ -1878,11 +1914,16 @@ int cmd_index_pack(int argc, const char **argv, const char *prefix)
 	for (i = 0; i < nr_objects; i++)
 		idx_objects[i] = &objects[i].idx;
 	curr_index = write_idx_file(index_name, idx_objects, nr_objects, &opts, pack_hash);
+	if (rev_index)
+		curr_rev_index = write_rev_file(rev_index_name, idx_objects,
+						nr_objects, pack_hash,
+						opts.flags);
 	free(idx_objects);
 
 	if (!verify)
 		final(pack_name, curr_pack,
 		      index_name, curr_index,
+		      rev_index_name, curr_rev_index,
 		      keep_msg, promisor_msg,
 		      pack_hash);
 	else
@@ -1893,10 +1934,13 @@ int cmd_index_pack(int argc, const char **argv, const char *prefix)
 
 	free(objects);
 	strbuf_release(&index_name_buf);
+	strbuf_release(&rev_index_name_buf);
 	if (pack_name == NULL)
 		free((void *) curr_pack);
 	if (index_name == NULL)
 		free((void *) curr_index);
+	if (rev_index_name == NULL)
+		free((void *) curr_rev_index);
 
 	/*
 	 * Let the caller know this pack is not self contained
diff --git a/t/t5325-reverse-index.sh b/t/t5325-reverse-index.sh
new file mode 100755
index 0000000000..2dae213126
--- /dev/null
+++ b/t/t5325-reverse-index.sh
@@ -0,0 +1,71 @@
+#!/bin/sh
+
+test_description='on-disk reverse index'
+. ./test-lib.sh
+
+packdir=.git/objects/pack
+
+test_expect_success 'setup' '
+	test_commit base &&
+
+	pack=$(git pack-objects --all $packdir/pack) &&
+	rev=$packdir/pack-$pack.rev &&
+
+	test_path_is_missing $rev
+'
+
+test_index_pack () {
+	rm -f $rev &&
+	conf=$1 &&
+	shift &&
+	# remove the index since Windows won't overwrite an existing file
+	rm $packdir/pack-$pack.idx &&
+	git -c pack.writeReverseIndex=$conf index-pack "$@" \
+		$packdir/pack-$pack.pack
+}
+
+test_expect_success 'index-pack with pack.writeReverseIndex' '
+	test_index_pack "" &&
+	test_path_is_missing $rev &&
+
+	test_index_pack false &&
+	test_path_is_missing $rev &&
+
+	test_index_pack true &&
+	test_path_is_file $rev
+'
+
+test_expect_success 'index-pack with --[no-]rev-index' '
+	for conf in "" true false
+	do
+		test_index_pack "$conf" --rev-index &&
+		test_path_exists $rev &&
+
+		test_index_pack "$conf" --no-rev-index &&
+		test_path_is_missing $rev
+	done
+'
+
+test_expect_success 'index-pack can verify reverse indexes' '
+	test_when_finished "rm -f $rev" &&
+	test_index_pack true &&
+
+	test_path_is_file $rev &&
+	git index-pack --rev-index --verify $packdir/pack-$pack.pack &&
+
+	# Intentionally corrupt the reverse index.
+	chmod u+w $rev &&
+	printf "xxxx" | dd of=$rev bs=1 count=4 conv=notrunc &&
+
+	test_must_fail git index-pack --rev-index --verify \
+		$packdir/pack-$pack.pack 2>err &&
+	grep "validation error" err
+'
+
+test_expect_success 'index-pack infers reverse index name with -o' '
+	git index-pack --rev-index -o other.idx $packdir/pack-$pack.pack &&
+	test_path_is_file other.idx &&
+	test_path_is_file other.rev
+'
+
+test_done

-- 
2.30.0.138.g6d7191ea01
Previous: Taylor BlauNext: Taylor Blau
Message 75 of 82 in “pack-revindex: introduce on-disk '.rev' format”
  1. 0/8 pack-revindex: introduce on-disk '.rev' formatTaylor Blau, Jan 8, 2021
  2. 2/8 pack-write.c: prepare to write 'pack-*.rev' filesTaylor Blau, Jan 8, 2021
  3. 8/8 pack-revindex: ensure that on-disk reverse indexes are given precedenceTaylor Blau, Jan 8, 2021
  4. 3/8 builtin/index-pack.c: write reverse indexesTaylor Blau, Jan 8, 2021
  5. 1/8 packfile: prepare for the existence of '*.rev' filesTaylor Blau, Jan 8, 2021
  6. 4/8 builtin/pack-objects.c: respect 'pack.writeReverseIndex'Taylor Blau, Jan 8, 2021
  7. 7/8 t: support GIT_TEST_WRITE_REV_INDEXTaylor Blau, Jan 8, 2021
  8. Derrick StoleeJan 12, 2021
  9. Taylor BlauJan 12, 2021
  10. Ævar Arnfjörð BjarmasonJan 12, 2021
  11. Derrick StoleeJan 12, 2021
  12. Taylor BlauJan 12, 2021
  13. 6/8 t: prepare for GIT_TEST_WRITE_REV_INDEXTaylor Blau, Jan 8, 2021
  14. Ævar Arnfjörð BjarmasonJan 12, 2021
  15. Taylor BlauJan 12, 2021
  16. 5/8 Documentation/config/pack.txt: advertise 'pack.writeReverseIndex'Taylor Blau, Jan 8, 2021
  17. 0/8 pack-revindex: introduce on-disk '.rev' formatTaylor Blau, Jan 13, 2021
  18. 8/8 pack-revindex: ensure that on-disk reverse indexes are given precedenceTaylor Blau, Jan 13, 2021
  19. 6/8 t: prepare for GIT_TEST_WRITE_REV_INDEXTaylor Blau, Jan 13, 2021
  20. 1/8 packfile: prepare for the existence of '*.rev' filesTaylor Blau, Jan 13, 2021
  21. Junio C HamanoJan 14, 2021
  22. Derrick StoleeJan 14, 2021
  23. Jeff KingJan 14, 2021
  24. Taylor BlauJan 14, 2021
  25. Junio C HamanoJan 14, 2021
  26. Taylor BlauJan 14, 2021
  27. Junio C HamanoJan 14, 2021
  28. Jeff KingJan 22, 2021
  29. Taylor BlauJan 25, 2021
  30. Jeff KingJan 25, 2021
  31. Junio C HamanoJan 25, 2021
  32. Taylor BlauJan 25, 2021
  33. 5/8 Documentation/config/pack.txt: advertise 'pack.writeReverseIndex'Taylor Blau, Jan 13, 2021
  34. 4/8 builtin/pack-objects.c: respect 'pack.writeReverseIndex'Taylor Blau, Jan 13, 2021
  35. Jeff KingJan 22, 2021
  36. Jeff KingJan 23, 2021
  37. Taylor BlauJan 25, 2021
  38. Jeff KingJan 25, 2021
  39. 2/8 pack-write.c: prepare to write 'pack-*.rev' filesTaylor Blau, Jan 13, 2021
  40. Jeff KingJan 22, 2021
  41. Taylor BlauJan 25, 2021
  42. Jeff KingJan 26, 2021
  43. 7/8 t: support GIT_TEST_WRITE_REV_INDEXTaylor Blau, Jan 13, 2021
  44. 3/8 builtin/index-pack.c: write reverse indexesTaylor Blau, Jan 13, 2021
  45. Jeff KingJan 22, 2021
  46. Taylor BlauJan 25, 2021
  47. 00/10 pack-revindex: introduce on-disk '.rev' formatTaylor Blau, Jan 25, 2021
  48. 01/10 packfile: prepare for the existence of '*.rev' filesTaylor Blau, Jan 25, 2021
  49. Jeff KingJan 29, 2021
  50. Taylor BlauJan 29, 2021
  51. Jeff KingJan 30, 2021
  52. 08/10 t: support GIT_TEST_WRITE_REV_INDEXTaylor Blau, Jan 25, 2021
  53. Jeff KingJan 29, 2021
  54. 07/10 t: prepare for GIT_TEST_WRITE_REV_INDEXTaylor Blau, Jan 25, 2021
  55. Jeff KingJan 29, 2021
  56. Eric SunshineJan 29, 2021
  57. Taylor BlauJan 29, 2021
  58. Jeff KingJan 30, 2021
  59. Junio C HamanoJan 29, 2021
  60. 05/10 builtin/pack-objects.c: respect 'pack.writeReverseIndex'Taylor Blau, Jan 25, 2021
  61. 09/10 pack-revindex: ensure that on-disk reverse indexes are given precedenceTaylor Blau, Jan 25, 2021
  62. Jeff KingJan 29, 2021
  63. Taylor BlauJan 29, 2021
  64. Jeff KingJan 30, 2021
  65. 10/10 t5325: check both on-disk and in-memory reverse indexTaylor Blau, Jan 25, 2021
  66. Jeff KingJan 29, 2021
  67. Jeff KingJan 29, 2021
  68. Taylor BlauJan 29, 2021
  69. Jeff KingJan 30, 2021
  70. 06/10 Documentation/config/pack.txt: advertise 'pack.writeReverseIndex'Taylor Blau, Jan 25, 2021
  71. Jeff KingJan 29, 2021
  72. Taylor BlauJan 29, 2021
  73. Jeff KingJan 30, 2021
  74. 02/10 pack-write.c: prepare to write 'pack-*.rev' filesTaylor Blau, Jan 25, 2021
  75. 04/10 builtin/index-pack.c: write reverse indexesTaylor Blau, Jan 25, 2021
  76. 03/10 builtin/index-pack.c: allow stripping arbitrary extensionsTaylor Blau, Jan 25, 2021
  77. Jeff KingJan 29, 2021
  78. Taylor BlauJan 29, 2021
  79. Junio C HamanoJan 26, 2021
  80. Taylor BlauJan 26, 2021
  81. Jeff KingJan 29, 2021
  82. Taylor BlauJan 29, 2021

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