diff options
Diffstat (limited to 'tests/realloc.c')
| -rw-r--r-- | tests/realloc.c | 73 |
1 files changed, 60 insertions, 13 deletions
diff --git a/tests/realloc.c b/tests/realloc.c index 05731396..62efd5a3 100644 --- a/tests/realloc.c +++ b/tests/realloc.c @@ -1,6 +1,6 @@ /* realloc() function that is glibc compatible. - Copyright (C) 1997, 2003-2004, 2006-2007, 2009-2024 Free Software + Copyright (C) 1997, 2003-2004, 2006-2007, 2009-2025 Free Software Foundation, Inc. This file is free software: you can redistribute it and/or modify @@ -18,17 +18,21 @@ /* written by Jim Meyering and Bruno Haible */ +/* Ensure that we call the system's realloc() below. */ +#define _GL_USE_STDLIB_ALLOC 1 #include <config.h> +#define _GL_REALLOC_INLINE _GL_EXTERN_INLINE #include <stdlib.h> #include <errno.h> +#include <stdckdint.h> -#include "xalloc-oversized.h" +#ifdef __CHERI_PURE_CAPABILITY__ +# include <cheri.h> +#endif -/* Call the system's realloc below. This file does not define - _GL_USE_STDLIB_ALLOC because it needs Gnulib's malloc if present. */ -#undef realloc +#ifndef _GL_INLINE_RPL_REALLOC /* Change the size of an allocated block of memory P to N bytes, with error checking. If P is NULL, use malloc. Otherwise if N is zero, @@ -37,27 +41,70 @@ void * rpl_realloc (void *p, size_t n) { - if (p == NULL) - return malloc (n); + size_t n1 = n; if (n == 0) { - free (p); - return NULL; +# if NEED_SANITIZED_REALLOC + /* When P is non-null, ISO C23 ยง7.24.3.7.(3) says realloc (P, 0) has + undefined behavior even though C17 and earlier partially defined + the behavior. Let the programmer know. + When the undefined-behaviour sanitizers report this case, i.e. when + <https://gcc.gnu.org/PR117233> and + <https://github.com/llvm/llvm-project/issues/113065> + have been closed and new releases of GCC and clang have been made, + we can revisit this code. */ + if (p != NULL) + abort (); +# endif + + /* realloc (NULL, 0) acts like glibc malloc (0), i.e., like malloc (1) + except the caller cannot dereference any non-null return. + + realloc (P, 0) with non-null P is a messier situation. + As mentioned above, C23 says behavior is undefined. + POSIX.1-2024 extends C17 to say realloc (P, 0) + either fails by setting errno and returning a null pointer, + or succeeds by freeing P and then either: + (a) setting errno=EINVAL and returning a null pointer; or + (b) acting like a successful malloc (0). + glibc 1 through 2.1 realloc acted like (b), + which conforms to C17, to C23 and to POSIX.1-2024. + glibc 2.1.1+ realloc acts like (a) except it does not set errno; + this conforms to C17 and to C23 but not to POSIX.1-2024. + Quite possibly future versions of POSIX will change, + due either to C23 or to (a)'s semantics being messy. + Act like (b), as that's easy, matches GNU, BSD and V7 malloc, + matches BSD and V7 realloc, and requires no extra code at + caller sites. */ + +# if !HAVE_REALLOC_0_NONNULL + n1 = 1; +# endif } - if (xalloc_oversized (n, 1)) +# if !HAVE_MALLOC_PTRDIFF + ptrdiff_t signed_n; + if (ckd_add (&signed_n, n, 0)) { errno = ENOMEM; return NULL; } +# endif - void *result = realloc (p, n); + void *result = realloc (p, n1); -#if !HAVE_MALLOC_POSIX +# if !HAVE_MALLOC_POSIX if (result == NULL) errno = ENOMEM; -#endif +# endif + +# ifdef __CHERI_PURE_CAPABILITY__ + if (result != NULL) + result = cheri_bounds_set (result, n); +# endif return result; } + +#endif |