lock_file: move static locks into functions

Placing `struct lock_file`s on the stack used to be a bad idea, because
the temp- and lockfile-machinery would keep a pointer into the struct.
But after 076aa2cbd (tempfile: auto-allocate tempfiles on heap,
2017-09-05), we can safely have lockfiles on the stack. (This applies
even if a user returns early, leaving a locked lock behind.)

Each of these `struct lock_file`s is used from within a single function.
Move them into the respective functions to make the scope clearer and
drop the staticness.

For good measure, I have inspected these sites and come to believe that
they always release the lock, with the possible exception of bailing out
using `die()` or `exit()` or by returning from a `cmd_foo()`.

As pointed out by Jeff King, it would be bad if someone held on to a
`struct lock_file *` for some reason. After some grepping, I agree with
his findings: no-one appears to be doing that.

After this commit, the remaining occurrences of "static struct
lock_file" are locks that are used from within different functions. That
is, they need to remain static. (Short of more intrusive changes like
passing around pointers to non-static locks.)

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 1 insertions, 2 deletions

diff --git a/builtin/rm.c b/builtin/rm.c
index 4447bb4..0fcb952 100644
--- a/builtin/rm.c
+++ b/builtin/rm.c
@@ -233,8 +233,6 @@ static int check_local_mod(struct object_id *head, int index_only)
 	return errs;
 }
 
-static struct lock_file lock_file;
-
 static int show_only = 0, force = 0, index_only = 0, recursive = 0, quiet = 0;
 static int ignore_unmatch = 0;
 
@@ -251,6 +249,7 @@ static struct option builtin_rm_options[] = {
 
 int cmd_rm(int argc, const char **argv, const char *prefix)
 {
+	struct lock_file lock_file = LOCK_INIT;
 	int i;
 	struct pathspec pathspec;
 	char *seen;