lockfile: remove function "hold_lock_file_for_append"

With 77b9b1d (add_to_alternates_file: don't add duplicate entries,
2015-08-10) the last caller of function "hold_lock_file_for_append"
has been removed, so we can remove the function as well.

Signed-off-by: Ralf Thielow <ralf.thielow@gmail.com>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

lockfile.c

@@ -177,44 +177,6 @@ int hold_lock_file_for_update_timeout(struct lock_file *lk, const char *path,
 	return fd;
 }
 
-int hold_lock_file_for_append(struct lock_file *lk, const char *path, int flags)
-{
-	int fd, orig_fd;
-
-	fd = lock_file(lk, path, flags);
-	if (fd < 0) {
-		if (flags & LOCK_DIE_ON_ERROR)
-			unable_to_lock_die(path, errno);
-		return fd;
-	}
-
-	orig_fd = open(path, O_RDONLY);
-	if (orig_fd < 0) {
-		if (errno != ENOENT) {
-			int save_errno = errno;
-
-			if (flags & LOCK_DIE_ON_ERROR)
-				die("cannot open '%s' for copying", path);
-			rollback_lock_file(lk);
-			error("cannot open '%s' for copying", path);
-			errno = save_errno;
-			return -1;
-		}
-	} else if (copy_fd(orig_fd, fd)) {
-		int save_errno = errno;
-
-		if (flags & LOCK_DIE_ON_ERROR)
-			die("failed to prepare '%s' for appending", path);
-		close(orig_fd);
-		rollback_lock_file(lk);
-		errno = save_errno;
-		return -1;
-	} else {
-		close(orig_fd);
-	}
-	return fd;
-}
-
 char *get_locked_file_path(struct lock_file *lk)
 {
 	struct strbuf ret = STRBUF_INIT;

lockfile.h

@@ -44,8 +44,7 @@
  *   throughout the life of the program (i.e. you cannot use an
  *   on-stack variable to hold this structure).
  *
- * * Attempts to create a lockfile by calling
- *   `hold_lock_file_for_update()` or `hold_lock_file_for_append()`.
+ * * Attempts to create a lockfile by calling `hold_lock_file_for_update()`.
  *
  * * Writes new content for the destination file by either:
  *
@@ -73,7 +72,7 @@
  * Even after the lockfile is committed or rolled back, the
  * `lock_file` object must not be freed or altered by the caller.
  * However, it may be reused; just pass it to another call of
- * `hold_lock_file_for_update()` or `hold_lock_file_for_append()`.
+ * `hold_lock_file_for_update()`.
  *
  * If the program exits before `commit_lock_file()`,
  * `commit_lock_file_to()`, or `rollback_lock_file()` is called, the
@@ -120,8 +119,7 @@ struct lock_file {
  * Flags
  * -----
  *
- * The following flags can be passed to `hold_lock_file_for_update()`
- * or `hold_lock_file_for_append()`.
+ * The following flags can be passed to `hold_lock_file_for_update()`.
  */
 
 /*
@@ -167,28 +165,18 @@ static inline int hold_lock_file_for_update(
 	return hold_lock_file_for_update_timeout(lk, path, flags, 0);
 }
 
-/*
- * Like `hold_lock_file_for_update()`, but before returning copy the
- * existing contents of the file (if any) to the lockfile and position
- * its write pointer at the end of the file. The flags argument and
- * error handling are described above.
- */
-extern int hold_lock_file_for_append(struct lock_file *lk,
-				     const char *path, int flags);
-
 /*
  * Append an appropriate error message to `buf` following the failure
- * of `hold_lock_file_for_update()` or `hold_lock_file_for_append()`
- * to lock `path`. `err` should be the `errno` set by the failing
- * call.
+ * of `hold_lock_file_for_update()` to lock `path`. `err` should be the
+ * `errno` set by the failing call.
  */
 extern void unable_to_lock_message(const char *path, int err,
 				   struct strbuf *buf);
 
 /*
  * Emit an appropriate error message and `die()` following the failure
- * of `hold_lock_file_for_update()` or `hold_lock_file_for_append()`
- * to lock `path`. `err` should be the `errno` set by the failing
+ * of `hold_lock_file_for_update()` to lock `path`. `err` should be the
+ * `errno` set by the failing
  * call.
  */
 extern NORETURN void unable_to_lock_die(const char *path, int err);