object-store: move and rename odb_pack_keep()

The function `odb_pack_keep()` creates a file at the passed-in path. If
this fails, then the function re-tries by first creating any potentially
missing leading directories and then trying to create the file once
again. As such, this function doesn't host any kind of logic that is
specific to the object store, but is rather a generic helper function.

Rename the function to `safe_create_file_with_leading_directories()` and
move it into "path.c". While at it, refactor it so that it loses its
dependency on `the_repository`.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: pks-t

builtin/fast-import.c

@@ -811,7 +811,8 @@ static char *keep_pack(const char *curr_index_name)
 	int keep_fd;
 
 	odb_pack_name(pack_data->repo, &name, pack_data->hash, "keep");
-	keep_fd = odb_pack_keep(name.buf);
+	keep_fd = safe_create_file_with_leading_directories(pack_data->repo,
+							    name.buf);
 	if (keep_fd < 0)
 		die_errno("cannot create keep file");
 	write_or_die(keep_fd, keep_msg, strlen(keep_msg));

builtin/index-pack.c

@@ -1565,7 +1565,7 @@ static void write_special_file(const char *suffix, const char *msg,
 	else
 		filename = odb_pack_name(the_repository, &name_buf, hash, suffix);
 
-	fd = odb_pack_keep(filename);
+	fd = safe_create_file_with_leading_directories(the_repository, filename);
 	if (fd < 0) {
 		if (errno != EEXIST)
 			die_errno(_("cannot write %s file '%s'"),

object-store.c

@@ -83,19 +83,6 @@ int odb_mkstemp(struct strbuf *temp_filename, const char *pattern)
 	return xmkstemp_mode(temp_filename->buf, mode);
 }
 
-int odb_pack_keep(const char *name)
-{
-	int fd;
-
-	fd = open(name, O_RDWR|O_CREAT|O_EXCL, 0600);
-	if (0 <= fd)
-		return fd;
-
-	/* slow path */
-	safe_create_leading_directories_const(the_repository, name);
-	return open(name, O_RDWR|O_CREAT|O_EXCL, 0600);
-}
-
 /*
  * Return non-zero iff the path is usable as an alternate object database.
  */

object-store.h

@@ -189,13 +189,6 @@ void raw_object_store_clear(struct raw_object_store *o);
  */
 int odb_mkstemp(struct strbuf *temp_filename, const char *pattern);
 
-/*
- * Create a pack .keep file named "name" (which should generally be the output
- * of odb_pack_name). Returns a file descriptor opened for writing, or -1 on
- * error.
- */
-int odb_pack_keep(const char *name);
-
 void *map_loose_object(struct repository *r, const struct object_id *oid,
 		       unsigned long *size);
 

path.c

@@ -1011,6 +1011,20 @@ enum scld_error safe_create_leading_directories_const(struct repository *repo,
 	return result;
 }
 
+int safe_create_file_with_leading_directories(struct repository *repo,
+					      const char *path)
+{
+	int fd;
+
+	fd = open(path, O_RDWR|O_CREAT|O_EXCL, 0600);
+	if (0 <= fd)
+		return fd;
+
+	/* slow path */
+	safe_create_leading_directories_const(repo, path);
+	return open(path, O_RDWR|O_CREAT|O_EXCL, 0600);
+}
+
 static int have_same_root(const char *path1, const char *path2)
 {
 	int is_abs1, is_abs2;

path.h

@@ -266,6 +266,13 @@ enum scld_error safe_create_leading_directories_const(struct repository *repo,
 						      const char *path);
 enum scld_error safe_create_leading_directories_no_share(char *path);
 
+/*
+ * Create a file, potentially creating its leading directories in case they
+ * don't exist. Returns the return value of the open(3p) call.
+ */
+int safe_create_file_with_leading_directories(struct repository *repo,
+					      const char *path);
+
 # ifdef USE_THE_REPOSITORY_VARIABLE
 #  include "strbuf.h"
 #  include "repository.h"