Re: [PATCH 1/2] config: check if config path is a file before parsing it

Jeff King [off-list ref] writes:

       a. actually check ferror() after getting EOF and report the read
          error. That catches EISDIR, along with any other unexpected
	  errors.

That is the most sensible, I would think (assuming that we really
get EISDIR instead of silent EOF).

       b. use an fopen wrapper that checks fstat(fileno(fh)) after the
          open, and turns fopen(some_dir) into an error.

That's already an option with FREAD_READS_DIRECTORIES, I think.

  2. It doesn't address the root problem for git_config_from_file(),
     which is that it is quiet when fopen fails, even if the reason is
     something interesting besides ENOENT. The caller can't check errno
     because it doesn't know if fopen() failed, or if the config
     callback returned an error.

Perhaps like this one as a starting point, with FREAD_READS_DIRECTORIES?

 config.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/config.c b/config.c
index 0dac0f4cb2..af8c01c8a3 100644
--- a/config.c
+++ b/config.c

@@ -1305,6 +1305,9 @@ int git_config_from_file(config_fn_t fn, const char *filename, void *data)
 	FILE *f;
 
 	f = fopen(filename, "r");
+	if (!f && errno != ENOENT)
+		die_errno("fopen('%s') failed", filename);
+
 	if (f) {
 		flockfile(f);
 		ret = do_config_from_file(fn, CONFIG_ORIGIN_FILE, filename, filename, f, data);