add helpers for detecting size_t overflow

diff --git a/wrapper.c b/wrapper.c
index 6fcaa4dc62b504078ea5202cfd7a096e79a83c5e..52001789ded0372becd3f55dda4cd1226c4b6dae 100644 (file)
--- a/wrapper.c
+++ b/wrapper.c
@@ -375,6 +375,19 @@ FILE *xfdopen(int fd, const char *mode)
        return stream;
 }
 
+FILE *fopen_for_writing(const char *path)
+{
+       FILE *ret = fopen(path, "w");
+
+       if (!ret && errno == EPERM) {
+               if (!unlink(path))
+                       ret = fopen(path, "w");
+               else
+                       errno = EPERM;
+       }
+       return ret;
+}
+
 int xmkstemp(char *template)
 {
        int fd;
@@ -601,18 +614,6 @@ int access_or_die(const char *path, int mode, unsigned flag)
        return ret;
 }
 
-struct passwd *xgetpwuid_self(void)
-{
-       struct passwd *pw;
-
-       errno = 0;
-       pw = getpwuid(getuid());
-       if (!pw)
-               die(_("unable to look up current user in the passwd file: %s"),
-                   errno ? strerror(errno) : _("no such user"));
-       return pw;
-}
-
 char *xgetcwd(void)
 {
        struct strbuf sb = STRBUF_INIT;