Introduce an unlink(2) wrapper which gives warning if unlink failed

This seem to be a very common pattern in the current code.

The function prints a generic removal failure message, the file name
which failed and readable errno presentation. The function preserves
errno and always returns the value unlink(2) returned, but prints
no message for ENOENT, as it was the most often filtered out in the
code calling unlink. Besides, removing a file is anyway the purpose of
calling unlink.

Signed-off-by: Alex Riesen <raa.lkml@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/git-compat-util.h b/git-compat-util.h
index 1ac16bde5ab853098f857a64c6f0fea9f4c3437f..c7cf2d5d9cdbfd4ed20c8b8ea49a36af7c138a4e 100644 (file)
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -415,4 +415,10 @@ void git_qsort(void *base, size_t nmemb, size_t size,
 #define fstat_is_reliable() 1
 #endif
 
+/*
+ * Preserves errno, prints a message, but gives no warning for ENOENT.
+ * Always returns the return value of unlink(2).
+ */
+int unlink_or_warn(const char *path);
+
 #endif

diff --git a/wrapper.c b/wrapper.c
index d8efb1365a01104db568633fa8f6aef0c67b4cd1..7eb3218ee995991881252e4bb599452d7214ae4f 100644 (file)
--- a/wrapper.c
+++ b/wrapper.c
@@ -289,3 +289,19 @@ int odb_pack_keep(char *name, size_t namesz, unsigned char *sha1)
        safe_create_leading_directories(name);
        return open(name, O_RDWR|O_CREAT|O_EXCL, 0600);
 }
+
+int unlink_or_warn(const char *file)
+{
+       int rc = unlink(file);
+
+       if (rc < 0) {
+               int err = errno;
+               if (ENOENT != err) {
+                       warning("unable to unlink %s: %s",
+                               file, strerror(errno));
+                       errno = err;
+               }
+       }
+       return rc;
+}
+