Merge branch 'tb/pack-finalize-ordering'

The order in which various files that make up a single (conceptual)
packfile has been reevaluated and straightened up.  This matters in
correctness, as an incomplete set of files must not be shown to a
running Git.

* tb/pack-finalize-ordering:
  pack-objects: rename .idx files into place after .bitmap files
  pack-write: split up finish_tmp_packfile() function
  builtin/index-pack.c: move `.idx` files into place last
  index-pack: refactor renaming in final()
  builtin/repack.c: move `.idx` files into place last
  pack-write.c: rename `.idx` files after `*.rev`
  pack-write: refactor renaming in finish_tmp_packfile()
  bulk-checkin.c: store checksum directly
  pack.h: line-wrap the definition of finish_tmp_packfile()

builtin/index-pack.c

@@ -1477,6 +1477,22 @@ static void write_special_file(const char *suffix, const char *msg,
 	strbuf_release(&name_buf);
 }
 
+static void rename_tmp_packfile(const char **final_name,
+				const char *curr_name,
+				struct strbuf *name, unsigned char *hash,
+				const char *ext, int make_read_only_if_same)
+{
+	if (*final_name != curr_name) {
+		if (!*final_name)
+			*final_name = odb_pack_name(name, hash, ext);
+		if (finalize_object_file(curr_name, *final_name))
+			die(_("unable to rename temporary '*.%s' file to '%s"),
+			    ext, *final_name);
+	} else if (make_read_only_if_same) {
+		chmod(*final_name, 0444);
+	}
+}
+
 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,
@@ -1505,31 +1521,13 @@ static void final(const char *final_pack_name, const char *curr_pack_name,
 		write_special_file("promisor", promisor_msg, final_pack_name,
 				   hash, NULL);
 
-	if (final_pack_name != curr_pack_name) {
+	rename_tmp_packfile(&final_pack_name, curr_pack_name, &pack_name,
-		if (!final_pack_name)
+			    hash, "pack", from_stdin);
-			final_pack_name = odb_pack_name(&pack_name, hash, "pack");
+	if (curr_rev_index_name)
-		if (finalize_object_file(curr_pack_name, final_pack_name))
+		rename_tmp_packfile(&final_rev_index_name, curr_rev_index_name,
-			die(_("cannot store pack file"));
+				    &rev_index_name, hash, "rev", 1);
-	} else if (from_stdin)
+	rename_tmp_packfile(&final_index_name, curr_index_name, &index_name,
-		chmod(final_pack_name, 0444);
+			    hash, "idx", 1);
-
-	if (final_index_name != curr_index_name) {
-		if (!final_index_name)
-			final_index_name = odb_pack_name(&index_name, hash, "idx");
-		if (finalize_object_file(curr_index_name, final_index_name))
-			die(_("cannot store index file"));
-	} 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;

builtin/pack-objects.c

@@ -1222,6 +1222,7 @@ static void write_pack_file(void)
 		if (!pack_to_stdout) {
 			struct stat st;
 			struct strbuf tmpname = STRBUF_INIT;
+			char *idx_tmp_name = NULL;
 
 			/*
 			 * Packs are runtime accessed in their mtime
@@ -1242,7 +1243,8 @@ static void write_pack_file(void)
 					warning_errno(_("failed utime() on %s"), pack_tmp_name);
 			}
 
-			strbuf_addf(&tmpname, "%s-", base_name);
+			strbuf_addf(&tmpname, "%s-%s.", base_name,
+				    hash_to_hex(hash));
 
 			if (write_bitmap_index) {
 				bitmap_writer_set_checksum(hash);
@@ -1250,13 +1252,14 @@ static void write_pack_file(void)
 					&to_pack, written_list, nr_written);
 			}
 
-			finish_tmp_packfile(&tmpname, pack_tmp_name,
+			stage_tmp_packfiles(&tmpname, pack_tmp_name,
 					    written_list, nr_written,
-					    &pack_idx_opts, hash);
+					    &pack_idx_opts, hash, &idx_tmp_name);
 
 			if (write_bitmap_index) {
-				strbuf_addf(&tmpname, "%s.bitmap", hash_to_hex(hash));
+				size_t tmpname_len = tmpname.len;
 
+				strbuf_addstr(&tmpname, "bitmap");
 				stop_progress(&progress_state);
 
 				bitmap_writer_show_progress(progress);
@@ -1266,8 +1269,12 @@ static void write_pack_file(void)
 				bitmap_writer_finish(written_list, nr_written,
 						     tmpname.buf, write_bitmap_options);
 				write_bitmap_index = 0;
+				strbuf_setlen(&tmpname, tmpname_len);
 			}
 
+			rename_tmp_packfile_idx(&tmpname, &idx_tmp_name);
+
+			free(idx_tmp_name);
 			strbuf_release(&tmpname);
 			free(pack_tmp_name);
 			puts(hash_to_hex(hash));

builtin/repack.c

@@ -208,10 +208,10 @@ static struct {
 	unsigned optional:1;
 } exts[] = {
 	{".pack"},
-	{".idx"},
 	{".rev", 1},
 	{".bitmap", 1},
 	{".promisor", 1},
+	{".idx"},
 };
 
 static unsigned populate_pack_exts(char *name)

bulk-checkin.c

@@ -23,9 +23,25 @@ static struct bulk_checkin_state {
 	uint32_t nr_written;
 } state;
 
+static void finish_tmp_packfile(struct strbuf *basename,
+				const char *pack_tmp_name,
+				struct pack_idx_entry **written_list,
+				uint32_t nr_written,
+				struct pack_idx_option *pack_idx_opts,
+				unsigned char hash[])
+{
+	char *idx_tmp_name = NULL;
+
+	stage_tmp_packfiles(basename, pack_tmp_name, written_list, nr_written,
+			    pack_idx_opts, hash, &idx_tmp_name);
+	rename_tmp_packfile_idx(basename, &idx_tmp_name);
+
+	free(idx_tmp_name);
+}
+
 static void finish_bulk_checkin(struct bulk_checkin_state *state)
 {
-	struct object_id oid;
+	unsigned char hash[GIT_MAX_RAWSZ];
 	struct strbuf packname = STRBUF_INIT;
 	int i;
 
@@ -37,19 +53,20 @@ static void finish_bulk_checkin(struct bulk_checkin_state *state)
 		unlink(state->pack_tmp_name);
 		goto clear_exit;
 	} else if (state->nr_written == 1) {
-		finalize_hashfile(state->f, oid.hash, CSUM_HASH_IN_STREAM | CSUM_FSYNC | CSUM_CLOSE);
+		finalize_hashfile(state->f, hash, CSUM_HASH_IN_STREAM | CSUM_FSYNC | CSUM_CLOSE);
 	} else {
-		int fd = finalize_hashfile(state->f, oid.hash, 0);
+		int fd = finalize_hashfile(state->f, hash, 0);
-		fixup_pack_header_footer(fd, oid.hash, state->pack_tmp_name,
+		fixup_pack_header_footer(fd, hash, state->pack_tmp_name,
-					 state->nr_written, oid.hash,
+					 state->nr_written, hash,
 					 state->offset);
 		close(fd);
 	}
 
-	strbuf_addf(&packname, "%s/pack/pack-", get_object_directory());
+	strbuf_addf(&packname, "%s/pack/pack-%s.", get_object_directory(),
+		    hash_to_hex(hash));
 	finish_tmp_packfile(&packname, state->pack_tmp_name,
 			    state->written, state->nr_written,
-			    &state->pack_idx_opts, oid.hash);
+			    &state->pack_idx_opts, hash);
 	for (i = 0; i < state->nr_written; i++)
 		free(state->written[i]);
 

pack-write.c

@@ -461,49 +461,48 @@ struct hashfile *create_tmp_packfile(char **pack_tmp_name)
 	return hashfd(fd, *pack_tmp_name);
 }
 
-void finish_tmp_packfile(struct strbuf *name_buffer,
+static void rename_tmp_packfile(struct strbuf *name_prefix, const char *source,
+				const char *ext)
+{
+	size_t name_prefix_len = name_prefix->len;
+
+	strbuf_addstr(name_prefix, ext);
+	if (rename(source, name_prefix->buf))
+		die_errno("unable to rename temporary file to '%s'",
+			  name_prefix->buf);
+	strbuf_setlen(name_prefix, name_prefix_len);
+}
+
+void rename_tmp_packfile_idx(struct strbuf *name_buffer,
+			     char **idx_tmp_name)
+{
+	rename_tmp_packfile(name_buffer, *idx_tmp_name, "idx");
+}
+
+void stage_tmp_packfiles(struct strbuf *name_buffer,
 			 const char *pack_tmp_name,
 			 struct pack_idx_entry **written_list,
 			 uint32_t nr_written,
 			 struct pack_idx_option *pack_idx_opts,
-			 unsigned char hash[])
+			 unsigned char hash[],
+			 char **idx_tmp_name)
 {
-	const char *idx_tmp_name, *rev_tmp_name = NULL;
+	const char *rev_tmp_name = NULL;
-	int basename_len = name_buffer->len;
 
 	if (adjust_shared_perm(pack_tmp_name))
 		die_errno("unable to make temporary pack file readable");
 
-	idx_tmp_name = write_idx_file(NULL, written_list, nr_written,
+	*idx_tmp_name = (char *)write_idx_file(NULL, written_list, nr_written,
-				      pack_idx_opts, hash);
+					       pack_idx_opts, hash);
-	if (adjust_shared_perm(idx_tmp_name))
+	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);
 
-	strbuf_addf(name_buffer, "%s.pack", hash_to_hex(hash));
+	rename_tmp_packfile(name_buffer, pack_tmp_name, "pack");
-
+	if (rev_tmp_name)
-	if (rename(pack_tmp_name, name_buffer->buf))
+		rename_tmp_packfile(name_buffer, rev_tmp_name, "rev");
-		die_errno("unable to rename temporary pack file");
-
-	strbuf_setlen(name_buffer, basename_len);
-
-	strbuf_addf(name_buffer, "%s.idx", hash_to_hex(hash));
-	if (rename(idx_tmp_name, name_buffer->buf))
-		die_errno("unable to rename temporary index file");
-
-	strbuf_setlen(name_buffer, basename_len);
-
-	if (rev_tmp_name) {
-		strbuf_addf(name_buffer, "%s.rev", hash_to_hex(hash));
-		if (rename(rev_tmp_name, name_buffer->buf))
-			die_errno("unable to rename temporary reverse-index file");
-	}
-
-	strbuf_setlen(name_buffer, basename_len);
-
-	free((void *)idx_tmp_name);
 }
 
 void write_promisor_file(const char *promisor_name, struct ref **sought, int nr_sought)

pack.h

@@ -110,6 +110,14 @@ int encode_in_pack_object_header(unsigned char *hdr, int hdr_len,
 int read_pack_header(int fd, struct pack_header *);
 
 struct hashfile *create_tmp_packfile(char **pack_tmp_name);
-void finish_tmp_packfile(struct strbuf *name_buffer, const char *pack_tmp_name, struct pack_idx_entry **written_list, uint32_t nr_written, struct pack_idx_option *pack_idx_opts, unsigned char sha1[]);
+void stage_tmp_packfiles(struct strbuf *name_buffer,
+			 const char *pack_tmp_name,
+			 struct pack_idx_entry **written_list,
+			 uint32_t nr_written,
+			 struct pack_idx_option *pack_idx_opts,
+			 unsigned char hash[],
+			 char **idx_tmp_name);
+void rename_tmp_packfile_idx(struct strbuf *basename,
+			     char **idx_tmp_name);
 
 #endif