[PATCH v7 13/40] builtin/apply: make apply_all_patches() return -1 on error

[Christian Couder <christian.couder@gmail.com>]

To finish libifying the apply functionality, apply_all_patches() should not
die() or exit() in case of error, but return -1.

While doing that we must take care that file descriptors are properly closed
and, if needed, reset a sensible value.

Also, according to the lockfile API, when finished with a lockfile, one
should either commit it or roll it back.

This is even more important now that the same lockfile can be passed
to init_apply_state() many times to be reused by series of calls to
the apply lib functions.

Helped-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Helped-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
---
 builtin/apply.c | 40 +++++++++++++++++++++++++++-------------
 1 file changed, 27 insertions(+), 13 deletions(-)

diff --git a/builtin/apply.c b/builtin/apply.c
index a27fdd3..c27be35 100644
--- a/builtin/apply.c
+++ b/builtin/apply.c
@@ -4558,7 +4558,7 @@ static int apply_all_patches(struct apply_state *state,
 		if (!strcmp(arg, "-")) {
 			res = apply_patch(state, 0, "<stdin>", options);
 			if (res < 0)
-				exit(1);
+				goto rollback_end;
 			errs |= res;
 			read_stdin = 0;
 			continue;
@@ -4568,21 +4568,23 @@ static int apply_all_patches(struct apply_state *state,
 					      arg);
 
 		fd = open(arg, O_RDONLY);
-		if (fd < 0)
-			die_errno(_("can't open patch '%s'"), arg);
+		if (fd < 0) {
+			error(_("can't open patch '%s': %s"), arg, strerror(errno));
+			goto rollback_end;
+		}
 		read_stdin = 0;
 		set_default_whitespace_mode(state);
 		res = apply_patch(state, fd, arg, options);
+		close(fd);
 		if (res < 0)
-			exit(1);
+			goto rollback_end;
 		errs |= res;
-		close(fd);
 	}
 	set_default_whitespace_mode(state);
 	if (read_stdin) {
 		res = apply_patch(state, 0, "<stdin>", options);
 		if (res < 0)
-			exit(1);
+			goto rollback_end;
 		errs |= res;
 	}
 
@@ -4596,11 +4598,13 @@ static int apply_all_patches(struct apply_state *state,
 				   squelched),
 				squelched);
 		}
-		if (state->ws_error_action == die_on_ws_error)
-			die(Q_("%d line adds whitespace errors.",
-			       "%d lines add whitespace errors.",
-			       state->whitespace_error),
-			    state->whitespace_error);
+		if (state->ws_error_action == die_on_ws_error) {
+			error(Q_("%d line adds whitespace errors.",
+				 "%d lines add whitespace errors.",
+				 state->whitespace_error),
+			      state->whitespace_error);
+			goto rollback_end;
+		}
 		if (state->applied_after_fixing_ws && state->apply)
 			warning("%d line%s applied after"
 				" fixing whitespace errors.",
@@ -4614,12 +4618,22 @@ static int apply_all_patches(struct apply_state *state,
 	}
 
 	if (state->update_index) {
-		if (write_locked_index(&the_index, state->lock_file, COMMIT_LOCK))
-			die(_("Unable to write new index file"));
+		res = write_locked_index(&the_index, state->lock_file, COMMIT_LOCK);
+		if (res) {
+			error(_("Unable to write new index file"));
+			goto rollback_end;
+		}
 		state->newfd = -1;
 	}
 
 	return !!errs;
+
+rollback_end:
+	if (state->newfd >= 0) {
+		rollback_lock_file(state->lock_file);
+		state->newfd = -1;
+	}
+	return -1;
 }
 
 int cmd_apply(int argc, const char **argv, const char *prefix)
-- 
2.9.0.rc2.411.g3e2ca28