pmt: revert 7f8090b

include/libgnulib/immutable.h

@@ -1,98 +0,0 @@
-/* Immutable data.
-
-   Copyright (C) 2021-2024 Free Software Foundation, Inc.
-
-   This file 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.
-
-   This file 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 this program.  If not, see <https://www.gnu.org/licenses/>.  */
-
-/* Written by Bruno Haible <bruno@clisp.org>, 2021.  */
-
-#ifndef _IMMUTABLE_H
-#define _IMMUTABLE_H
-
-/* This file provide a facility to allocate and free immutable data objects.
-
-   An immutable data object is allocated in three steps:
-     1. You allocate an immutable memory region.
-          DATA *wp = immmalloc (sizeof (*wp));
-        The pointer wp is actually a writable view to the memory region.
-     2. You fill the memory region, through the pointer wp:
-          wp->x = ...;
-          wp->y = ...;
-          ...
-     3. You declare the memory region as frozen.  This means that you relinquish
-        write access.
-          DATA const *p = immfreeze (wp);
-        You can now let wp get out-of-scope.
-
-   Then the pointer p can be used only in read-only ways.  That is, if you cast
-   away the 'const' and attempt to write to the memory region, it will crash at
-   runtime (through a SIGSEGV signal).
-     p->x = ...;             // rejected by the compiler
-     ((DATA *) p)->x = ...;  // crashes at runtime
-
-   Finally, you can free the immutable data object:
-     immfree (p);
- */
-
-/* If you compile this module with the C macro NO_IMMUTABLE set to 1, or on a
-   platform that lacks support for read-only and writeable memory areas, the
-   functions work alike, except that the "read-only" pointers are actually
-   writable.  */
-
-/* This file uses HAVE_WORKING_MPROTECT.  */
-#if !_GL_CONFIG_H_INCLUDED
- #error "Please include config.h first."
-#endif
-
-#include <stddef.h>
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/* This macro tells whether the implementation effectively rejects writes to
-   immutable data.  */
-#if !NO_IMMUTABLE && ((defined _WIN32 && !defined __CYGWIN__) || HAVE_WORKING_MPROTECT)
-# define IMMUTABLE_EFFECTIVE 1
-#else
-# define IMMUTABLE_EFFECTIVE 0
-#endif
-
-/* Allocates an immutable memory region.
-   SIZE if the number of bytes; should be > 0.
-   Returns a writeable pointer to the memory region.
-   Upon memory allocation failure, returns NULL with errno set to ENOMEM.  */
-extern void * immmalloc (size_t size);
-
-/* Freezes an immutable memory region.
-   WRITABLE_POINTER is a non-NULL return value from immmalloc().
-   Returns a read-only pointer to the same memory region.  */
-extern const void * immfreeze (void *writable_pointer);
-
-/* Frees an immutable memory region.
-   READONLY_POINTER is a return value from immfreeze().  */
-extern void immfree (const void *readonly_pointer);
-
-/* The following is just an application to some data types.  */
-
-/* Allocates an immutable memory region that contains a copy of the given string.
-   Returns a read-only pointer to this duplicated string.
-   Upon memory allocation failure, returns NULL with errno set to ENOMEM.  */
-extern const char * immstrdup (const char *string);
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* _IMMUTABLE_H */