From 29064d02c31b08ae41d41a93fd1439718373b196 Mon Sep 17 00:00:00 2001 From: Philipp Stephani Date: Thu, 24 Dec 2020 16:48:40 +0100 Subject: Update Gnulib. All changes in this commit are autogenerated by running admin/merge-gnulib. --- lib/malloc/scratch_buffer_grow_preserve.c | 67 +++++++++++++++++++++++++++++++ 1 file changed, 67 insertions(+) create mode 100644 lib/malloc/scratch_buffer_grow_preserve.c (limited to 'lib/malloc/scratch_buffer_grow_preserve.c') diff --git a/lib/malloc/scratch_buffer_grow_preserve.c b/lib/malloc/scratch_buffer_grow_preserve.c new file mode 100644 index 00000000000..aef232938d5 --- /dev/null +++ b/lib/malloc/scratch_buffer_grow_preserve.c @@ -0,0 +1,67 @@ +/* Variable-sized buffer with on-stack default allocation. + Copyright (C) 2015-2020 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 General Public + License as published by the Free Software Foundation; either + version 3 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 + General Public License for more details. + + You should have received a copy of the GNU General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _LIBC +# include +#endif + +#include +#include +#include + +bool +__libc_scratch_buffer_grow_preserve (struct scratch_buffer *buffer) +{ + size_t new_length = 2 * buffer->length; + void *new_ptr; + + if (buffer->data == buffer->__space.__c) + { + /* Move buffer to the heap. No overflow is possible because + buffer->length describes a small buffer on the stack. */ + new_ptr = malloc (new_length); + if (new_ptr == NULL) + return false; + memcpy (new_ptr, buffer->__space.__c, buffer->length); + } + else + { + /* Buffer was already on the heap. Check for overflow. */ + if (__glibc_likely (new_length >= buffer->length)) + new_ptr = realloc (buffer->data, new_length); + else + { + __set_errno (ENOMEM); + new_ptr = NULL; + } + + if (__glibc_unlikely (new_ptr == NULL)) + { + /* Deallocate, but buffer must remain valid to free. */ + free (buffer->data); + scratch_buffer_init (buffer); + return false; + } + } + + /* Install new heap-based buffer. */ + buffer->data = new_ptr; + buffer->length = new_length; + return true; +} +libc_hidden_def (__libc_scratch_buffer_grow_preserve) -- cgit v1.2.3