Remove unused scratch_buffer_dupfree

Turns out scratch_buffer_dupfree internal API was unused since

commit ef0700004b
stdlib: Simplify buffer management in canonicalize

And the related test in malloc/tst-scratch_buffer had issues
so it's better to remove it completely.

Reviewed-by: Florian Weimer <fweimer@redhat.com>

include/scratch_buffer.h

@@ -132,20 +132,4 @@ 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 */

malloc/Makefile

@@ -123,7 +123,6 @@ tests-mcheck = $(filter-out $(tests-exclude-mcheck) $(tests-static), $(tests))
 endif
 
 routines = malloc mcheck mtrace obstack reallocarray \
-  scratch_buffer_dupfree \
   scratch_buffer_grow scratch_buffer_grow_preserve \
   scratch_buffer_set_array_size \
   dynarray_at_failure \

malloc/Versions

@@ -75,7 +75,6 @@ libc {
     __libc_thread_freeres;
 
     # struct scratch_buffer support
-    __libc_scratch_buffer_dupfree;
     __libc_scratch_buffer_grow;
     __libc_scratch_buffer_grow_preserve;
     __libc_scratch_buffer_set_array_size;

malloc/scratch_buffer_dupfree.c

@@ -1,41 +0,0 @@
-/* Variable-sized buffer with on-stack default allocation.
-   Copyright (C) 2020-2022 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library; if not, see
-   <https://www.gnu.org/licenses/>.  */
-
-#ifndef _LIBC
-# include <libc-config.h>
-#endif
-
-#include <scratch_buffer.h>
-#include <string.h>
-
-void *
-__libc_scratch_buffer_dupfree (struct scratch_buffer *buffer, size_t size)
-{
-  void *data = buffer->data;
-  if (data == buffer->__space.__c)
-    {
-      void *copy = malloc (size);
-      return copy != NULL ? memcpy (copy, data, size) : NULL;
-    }
-  else
-    {
-      void *copy = realloc (data, size);
-      return copy != NULL ? copy : data;
-    }
-}
-libc_hidden_def (__libc_scratch_buffer_dupfree)

malloc/tst-scratch_buffer.c

@@ -151,26 +151,6 @@ do_test (void)
 	  && array_size_must_fail (4, ((size_t)-1) / 4)))
 	return 1;
   }
-  {
-    struct scratch_buffer buf;
-    scratch_buffer_init (&buf);
-    memset (buf.data, '@', buf.length);
-
-    size_t sizes[] = { 16, buf.length, buf.length + 16 };
-    for (int i = 0; i < array_length (sizes); i++)
-      {
-        /* The extra size is unitialized through realloc.  */
-        size_t l = sizes[i] > buf.length ? sizes[i] : buf.length;
-        void *r = scratch_buffer_dupfree (&buf, l);
-        void *c = xmalloc (l);
-        memset (c, '@', l);
-        TEST_COMPARE_BLOB (r, l, buf.data, l);
-        free (r);
-        free (c);
-      }
-
-    scratch_buffer_free (&buf);
-  }
   return 0;
 }