mkstemps, mkostemps: new modules

[gnulib.git] / lib / fstatat.c

diff --git a/lib/fstatat.c b/lib/fstatat.c
index 59d7422..1c6c2d3 100644 (file)
--- a/lib/fstatat.c
+++ b/lib/fstatat.c
@@ -25,7 +25,9 @@
 #include <fcntl.h>
 #include <string.h>
 
-#undef fstatat
+#if HAVE_FSTATAT
+
+# undef fstatat
 
 /* fstatat should always follow symbolic links that end in /, but on
    Solaris 9 it doesn't if AT_SYMLINK_NOFOLLOW is specified.
@@ -62,3 +64,47 @@ rpl_fstatat (int fd, char const *file, struct stat *st, int flag)
     }
   return result;
 }
+
+#else /* !HAVE_FSTATAT */
+
+/* On mingw, the gnulib <sys/stat.h> defines `stat' as a function-like
+   macro; but using it in AT_FUNC_F2 causes compilation failure
+   because the preprocessor sees a use of a macro that requires two
+   arguments but is only given one.  Hence, we need an inline
+   forwarder to get past the preprocessor.  */
+static inline int
+stat_func (char const *name, struct stat *st)
+{
+  return stat (name, st);
+}
+
+/* Likewise, if there is no native `lstat', then the gnulib
+   <sys/stat.h> defined it as stat, which also needs adjustment.  */
+# if !HAVE_LSTAT
+#  undef lstat
+#  define lstat stat_func
+# endif
+
+/* Replacement for Solaris' function by the same name.
+   <http://www.google.com/search?q=fstatat+site:docs.sun.com>
+   First, try to simulate it via l?stat ("/proc/self/fd/FD/FILE").
+   Failing that, simulate it via save_cwd/fchdir/(stat|lstat)/restore_cwd.
+   If either the save_cwd or the restore_cwd fails (relatively unlikely),
+   then give a diagnostic and exit nonzero.
+   Otherwise, this function works just like Solaris' fstatat.  */
+
+# define AT_FUNC_NAME fstatat
+# define AT_FUNC_F1 lstat
+# define AT_FUNC_F2 stat_func
+# define AT_FUNC_USE_F1_COND AT_SYMLINK_NOFOLLOW
+# define AT_FUNC_POST_FILE_PARAM_DECLS , struct stat *st, int flag
+# define AT_FUNC_POST_FILE_ARGS        , st
+# include "at-func.c"
+# undef AT_FUNC_NAME
+# undef AT_FUNC_F1
+# undef AT_FUNC_F2
+# undef AT_FUNC_USE_F1_COND
+# undef AT_FUNC_POST_FILE_PARAM_DECLS
+# undef AT_FUNC_POST_FILE_ARGS
+
+#endif /* !HAVE_FSTATAT */