[PATCH] merge-file: correctly open files when in a subdir

From: Aleksander Boruch-Gruszecki <aleksander.boruchgruszecki@gmail.com>
Date: Feb 8, 2015, 16:53 UTC
Message-ID: <CAPHKiG7yP=QZBVdDbyQp=uyMX0EsmUqgO-LO8pscn7hcbP0RCw@mail.gmail.com>

run_setup_gently() is called before merge-file. This may result in changing current working directory, which wasn't taken into account when opening a file for writing.

Fix by prepending the passed prefix. Previous var is left so that error messages keep referring to the file from the user's working directory perspective.

Signed-off-by: Aleksander Boruch-Gruszecki
    <aleksander.boruchgruszecki@gmail.com>
---
I'm sorry if I'm sending the copies to wrong people, but I had no idea
who to send them to since there were barely any changes to the file.
Since the fix is so trivial I didn't add any tests, but I can create
some if they're needed.

 builtin/merge-file.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/builtin/merge-file.c b/builtin/merge-file.c
index 844f84f..232b768 100644
--- a/builtin/merge-file.c
+++ b/builtin/merge-file.c
@@ -90,7 +90,8 @@ int cmd_merge_file(int argc, const char **argv,
const char *prefix)

     if (ret >= 0) {
         const char *filename = argv[0];
-        FILE *f = to_stdout ? stdout : fopen(filename, "wb");
+        const char *fpath = prefix_filename(prefix, prefixlen, argv[0]);
+        FILE *f = to_stdout ? stdout : fopen(fpath, "wb");

         if (!f)
             ret = error("Could not open %s for writing", filename);

-- 
1.9.1