malloc: Add scratch_buffer_dupfree

It returns a copy of the buffer up to a defined size.  It will be used
on realpath sync with gnulib.

1 files changed, 16 insertions, 0 deletions

diff --git a/include/scratch_buffer.h b/include/scratch_buffer.h
index f51456444f..36d0bef4bb 100644
--- a/include/scratch_buffer.h
+++ b/include/scratch_buffer.h
@@ -132,4 +132,20 @@ scratch_buffer_set_array_size (struct scratch_buffer *buffer,
 			 (buffer, nelem, size));
 }
 
+/* Return a copy of *BUFFER's first SIZE bytes as a heap-allocated block,
+   deallocating *BUFFER if it was heap-allocated.  SIZE must be at
+   most *BUFFER's size.  Return NULL (setting errno) on memory
+   exhaustion.  */
+void *__libc_scratch_buffer_dupfree (struct scratch_buffer *buffer,
+                                     size_t size);
+libc_hidden_proto (__libc_scratch_buffer_dupfree)
+
+/* Alias for __libc_scratch_dupfree.  */
+static __always_inline void *
+scratch_buffer_dupfree (struct scratch_buffer *buffer, size_t size)
+{
+  void *r = __libc_scratch_buffer_dupfree (buffer, size);
+  return __glibc_likely (r != NULL) ? r : NULL;
+}
+
 #endif /* _SCRATCH_BUFFER_H */