diff mbox series

[RFC,13/15] pack-write API: pass down "verify" not arbitrary flags

Message ID RFC-patch-13.15-63eeb66185a-20220603T183608Z-avarab@gmail.com (mailing list archive)
State New, archived
Headers show
Series Fix GCC -fanalyzer warnings & add -fanalyzer DEVOPTS mode | expand

Commit Message

Ævar Arnfjörð Bjarmason June 3, 2022, 6:37 p.m. UTC
Change the pack-write API to accept a boolean "verify" parameter
instead of passing down the "struct pack_idx_option" flags directly.

This simplifies the code for both humans and machines, e.g. GCC's
-fanalyzer would correctly note that there were potential paths
through this code where we'd deference NULL, but in reality we
wouldn't hit them because certain flags would always go hand-in-hand.

Let's instead separate the underlying API from the total set of flags,
and stop passing the flags down to functions that don't need the full
set of flags, they'll just get the specific state they need.

See e37d0b8730b (builtin/index-pack.c: write reverse indexes,
2021-01-25) for the initial implementation, and [1] for the initial
WIP version of this commit on the ML.

1. https://lore.kernel.org/git/87v93bidhn.fsf@evledraar.gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 builtin/fast-import.c  |  2 +-
 builtin/index-pack.c   | 35 ++++++++++++++---------------------
 builtin/pack-objects.c |  9 +++------
 midx.c                 |  2 +-
 pack-write.c           | 38 +++++++++++++++++---------------------
 pack.h                 | 15 ++++++---------
 6 files changed, 42 insertions(+), 59 deletions(-)
diff mbox series

Patch

diff --git a/builtin/fast-import.c b/builtin/fast-import.c
index 28d3193c380..7cd2a3b8203 100644
--- a/builtin/fast-import.c
+++ b/builtin/fast-import.c
@@ -787,7 +787,7 @@  static const char *create_index(void)
 		die("internal consistency error creating the index");
 
 	tmpfile = write_idx_file(NULL, idx, object_count, &pack_idx_opts,
-				 pack_data->hash);
+				 pack_data->hash, 0);
 	free(idx);
 	return tmpfile;
 }
diff --git a/builtin/index-pack.c b/builtin/index-pack.c
index 3e385b48002..6691c5836e4 100644
--- a/builtin/index-pack.c
+++ b/builtin/index-pack.c
@@ -1589,12 +1589,9 @@  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;
-	}
+	if (!strcmp(k, "pack.writereverseindex"))
+		opts->write_rev = git_config_bool(k, v);
+
 	return git_default_config(k, v, cb);
 }
 
@@ -1713,7 +1710,7 @@  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, rev_index;
+	int i, fix_thin_pack = 0, verify = 0, stat_only = 0;
 	const char *curr_index;
 	const char *curr_rev_index = NULL;
 	const char *index_name = NULL, *pack_name = NULL, *rev_index_name = NULL;
@@ -1747,10 +1744,8 @@  int cmd_index_pack(int argc, const char **argv, const char *prefix)
 	if (prefix && chdir(prefix))
 		die(_("Cannot come back to cwd"));
 
-	if (git_env_bool(GIT_TEST_WRITE_REV_INDEX, 0))
-		rev_index = 1;
-	else
-		rev_index = !!(opts.flags & (WRITE_REV_VERIFY | WRITE_REV));
+	opts.write_rev = git_env_bool(GIT_TEST_WRITE_REV_INDEX,
+				       opts.write_rev);
 
 	for (i = 1; i < argc; i++) {
 		const char *arg = argv[i];
@@ -1835,9 +1830,9 @@  int cmd_index_pack(int argc, const char **argv, const char *prefix)
 					die(_("unknown hash algorithm '%s'"), arg);
 				repo_set_hash_algo(the_repository, hash_algo);
 			} else if (!strcmp(arg, "--rev-index")) {
-				rev_index = 1;
+				opts.write_rev = 1;
 			} else if (!strcmp(arg, "--no-rev-index")) {
-				rev_index = 0;
+				opts.write_rev = 0;
 			} else
 				usage(index_pack_usage);
 			continue;
@@ -1859,9 +1854,7 @@  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 (opts.write_rev) {
 		if (index_name)
 			rev_index_name = derive_filename(index_name,
 							 "idx", "rev",
@@ -1872,10 +1865,9 @@  int cmd_index_pack(int argc, const char **argv, const char *prefix)
 		if (!index_name)
 			die(_("--verify with no packfile name given"));
 		read_idx_option(&opts, index_name);
-		opts.flags |= WRITE_IDX_VERIFY | WRITE_IDX_STRICT;
 	}
 	if (strict)
-		opts.flags |= WRITE_IDX_STRICT;
+		opts.write_idx_strict = 1;
 
 	if (HAVE_THREADS && !nr_threads) {
 		nr_threads = online_cpus();
@@ -1919,11 +1911,12 @@  int cmd_index_pack(int argc, const char **argv, const char *prefix)
 	ALLOC_ARRAY(idx_objects, nr_objects);
 	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_index = write_idx_file(index_name, idx_objects, nr_objects, &opts,
+				    pack_hash, verify);
+	if (opts.write_rev)
 		curr_rev_index = write_rev_file(rev_index_name, idx_objects,
 						nr_objects, pack_hash,
-						opts.flags);
+						verify);
 	free(idx_objects);
 
 	if (!verify)
diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index 014dcd4bc98..6aeaad8560f 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -3160,10 +3160,7 @@  static int git_pack_config(const char *k, const char *v, void *cb)
 		return 0;
 	}
 	if (!strcmp(k, "pack.writereverseindex")) {
-		if (git_config_bool(k, v))
-			pack_idx_opts.flags |= WRITE_REV;
-		else
-			pack_idx_opts.flags &= ~WRITE_REV;
+		pack_idx_opts.write_rev = git_config_bool(k, v);
 		return 0;
 	}
 	if (!strcmp(k, "uploadpack.blobpackfileuri")) {
@@ -4007,8 +4004,8 @@  int cmd_pack_objects(int argc, const char **argv, const char *prefix)
 
 	reset_pack_idx_option(&pack_idx_opts);
 	git_config(git_pack_config, NULL);
-	if (git_env_bool(GIT_TEST_WRITE_REV_INDEX, 0))
-		pack_idx_opts.flags |= WRITE_REV;
+	pack_idx_opts.write_rev = git_env_bool(GIT_TEST_WRITE_REV_INDEX,
+					       pack_idx_opts.write_rev);
 
 	progress = isatty(2);
 	argc = parse_options(argc, argv, prefix, pack_objects_options,
diff --git a/midx.c b/midx.c
index 3db0e47735f..f0bb56b2c64 100644
--- a/midx.c
+++ b/midx.c
@@ -905,7 +905,7 @@  static void write_midx_reverse_index(char *midx_name, unsigned char *midx_hash,
 	strbuf_addf(&buf, "%s-%s.rev", midx_name, hash_to_hex(midx_hash));
 
 	tmp_file = write_rev_file_order(NULL, ctx->pack_order, ctx->entries_nr,
-					midx_hash, WRITE_REV);
+					midx_hash, 0);
 
 	if (finalize_object_file(tmp_file, buf.buf))
 		die(_("cannot store reverse index file"));
diff --git a/pack-write.c b/pack-write.c
index 51812cb1299..7973aa75579 100644
--- a/pack-write.c
+++ b/pack-write.c
@@ -44,7 +44,7 @@  static int need_large_offset(off_t offset, const struct pack_idx_option *opts)
  */
 const char *write_idx_file(const char *index_name, struct pack_idx_entry **objects,
 			   int nr_objects, const struct pack_idx_option *opts,
-			   const unsigned char *sha1)
+			   const unsigned char *sha1, int verify)
 {
 	struct hashfile *f;
 	struct pack_idx_entry **sorted_by_sha, **list, **last;
@@ -65,7 +65,7 @@  const char *write_idx_file(const char *index_name, struct pack_idx_entry **objec
 	else
 		sorted_by_sha = list = last = NULL;
 
-	if (opts->flags & WRITE_IDX_VERIFY) {
+	if (verify) {
 		assert(index_name);
 		f = hashfd_check(index_name);
 	} else {
@@ -117,7 +117,7 @@  const char *write_idx_file(const char *index_name, struct pack_idx_entry **objec
 		if (index_version < 2)
 			hashwrite_be32(f, obj->offset);
 		hashwrite(f, obj->oid.hash, the_hash_algo->rawsz);
-		if ((opts->flags & WRITE_IDX_STRICT) &&
+		if (opts->write_idx_strict &&
 		    (i && oideq(&list[-2]->oid, &obj->oid)))
 			die("The same object %s appears twice in the pack",
 			    oid_to_hex(&obj->oid));
@@ -159,9 +159,10 @@  const char *write_idx_file(const char *index_name, struct pack_idx_entry **objec
 	}
 
 	hashwrite(f, sha1, the_hash_algo->rawsz);
+
 	finalize_hashfile(f, NULL, FSYNC_COMPONENT_PACK_METADATA,
 			  CSUM_HASH_IN_STREAM | CSUM_CLOSE |
-			  ((opts->flags & WRITE_IDX_VERIFY) ? 0 : CSUM_FSYNC));
+			  (verify ? 0 : CSUM_FSYNC));
 	return index_name;
 }
 
@@ -216,22 +217,19 @@  const char *write_rev_file(const char *rev_name,
 			   struct pack_idx_entry **objects,
 			   uint32_t nr_objects,
 			   const unsigned char *hash,
-			   unsigned flags)
+			   int verify)
 {
 	uint32_t *pack_order;
 	uint32_t i;
 	const char *ret;
 
-	if (!(flags & WRITE_REV) && !(flags & WRITE_REV_VERIFY))
-		return NULL;
-
 	ALLOC_ARRAY(pack_order, nr_objects);
 	for (i = 0; i < nr_objects; i++)
 		pack_order[i] = i;
 	QSORT_S(pack_order, nr_objects, pack_order_cmp, objects);
 
 	ret = write_rev_file_order(rev_name, pack_order, nr_objects, hash,
-				   flags);
+				   verify);
 
 	free(pack_order);
 
@@ -242,15 +240,12 @@  const char *write_rev_file_order(const char *rev_name,
 				 uint32_t *pack_order,
 				 uint32_t nr_objects,
 				 const unsigned char *hash,
-				 unsigned flags)
+				 int verify)
 {
 	struct hashfile *f;
 	int fd;
 
-	if ((flags & WRITE_REV) && (flags & WRITE_REV_VERIFY))
-		die(_("cannot both write and verify reverse index"));
-
-	if (flags & WRITE_REV) {
+	if (!verify) {
 		if (!rev_name) {
 			struct strbuf tmp_file = STRBUF_INIT;
 			fd = odb_mkstemp(&tmp_file, "pack/tmp_rev_XXXXXX");
@@ -260,7 +255,7 @@  const char *write_rev_file_order(const char *rev_name,
 			fd = xopen(rev_name, O_CREAT|O_EXCL|O_WRONLY, 0600);
 		}
 		f = hashfd(fd, rev_name);
-	} else if (flags & WRITE_REV_VERIFY) {
+	} else {
 		struct stat statbuf;
 		if (stat(rev_name, &statbuf)) {
 			if (errno == ENOENT) {
@@ -270,8 +265,7 @@  const char *write_rev_file_order(const char *rev_name,
 				die_errno(_("could not stat: %s"), rev_name);
 		}
 		f = hashfd_check(rev_name);
-	} else
-		return NULL;
+	}
 
 	write_rev_header(f);
 
@@ -283,7 +277,8 @@  const char *write_rev_file_order(const char *rev_name,
 
 	finalize_hashfile(f, NULL, FSYNC_COMPONENT_PACK_METADATA,
 			  CSUM_HASH_IN_STREAM | CSUM_CLOSE |
-			  ((flags & WRITE_IDX_VERIFY) ? 0 : CSUM_FSYNC));
+			  (verify ? 0 : CSUM_FSYNC));
+
 
 	return rev_name;
 }
@@ -494,12 +489,13 @@  void stage_tmp_packfiles(struct strbuf *name_buffer,
 		die_errno("unable to make temporary pack file readable");
 
 	*idx_tmp_name = (char *)write_idx_file(NULL, written_list, nr_written,
-					       pack_idx_opts, hash);
+					       pack_idx_opts, hash, 0);
 	if (adjust_shared_perm(*idx_tmp_name))
 		die_errno("unable to make temporary index file readable");
 
-	rev_tmp_name = write_rev_file(NULL, written_list, nr_written, hash,
-				      pack_idx_opts->flags);
+	if (pack_idx_opts->write_rev)
+		rev_tmp_name = write_rev_file(NULL, written_list, nr_written, hash,
+					      0);
 
 	rename_tmp_packfile(name_buffer, pack_tmp_name, "pack");
 	if (rev_tmp_name)
diff --git a/pack.h b/pack.h
index 802c047efe6..ccc4c129b0c 100644
--- a/pack.h
+++ b/pack.h
@@ -38,12 +38,8 @@  struct pack_header {
 #define PACK_IDX_SIGNATURE 0xff744f63	/* "\377tOc" */
 
 struct pack_idx_option {
-	unsigned flags;
-	/* flag bits */
-#define WRITE_IDX_VERIFY 01 /* verify only, do not write the idx file */
-#define WRITE_IDX_STRICT 02
-#define WRITE_REV 04
-#define WRITE_REV_VERIFY 010
+	unsigned int write_idx_strict:1,
+		     write_rev:1;
 
 	uint32_t version;
 	uint32_t off32_limit;
@@ -84,7 +80,8 @@  typedef int (*verify_fn)(const struct object_id *, enum object_type, unsigned lo
 const char *write_idx_file(const char *index_name,
 			   struct pack_idx_entry **objects, int nr_objects,
 			   const struct pack_idx_option *opts,
-			   const unsigned char *sha1);
+			   const unsigned char *sha1,
+			   int verify);
 int check_pack_crc(struct packed_git *p, struct pack_window **w_curs, off_t offset, off_t len, unsigned int nr);
 int verify_pack_index(struct packed_git *);
 int verify_pack(struct repository *, struct packed_git *, verify_fn fn, struct progress *, uint32_t);
@@ -99,11 +96,11 @@  void write_promisor_file(const char *promisor_name, struct ref **sought, int nr_
 const char *write_rev_file(const char *rev_name,
 			   struct pack_idx_entry **objects,
 			   uint32_t nr_objects,
-			   const unsigned char *hash, unsigned flags);
+			   const unsigned char *hash, int verify);
 const char *write_rev_file_order(const char *rev_name, uint32_t *pack_order,
 				 uint32_t nr_objects,
 				 const unsigned char *hash,
-				 unsigned flags);
+				 int verify);
 
 /*
  * The "hdr" output buffer should be at least this big, which will handle sizes