| /* alloc.c -- Memory allocation without mmap. |
| Copyright (C) 2012-2024 Free Software Foundation, Inc. |
| Written by Ian Lance Taylor, Google. |
| |
| Redistribution and use in source and binary forms, with or without |
| modification, are permitted provided that the following conditions are |
| met: |
| |
| (1) Redistributions of source code must retain the above copyright |
| notice, this list of conditions and the following disclaimer. |
| |
| (2) Redistributions in binary form must reproduce the above copyright |
| notice, this list of conditions and the following disclaimer in |
| the documentation and/or other materials provided with the |
| distribution. |
| |
| (3) The name of the author may not be used to |
| endorse or promote products derived from this software without |
| specific prior written permission. |
| |
| THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED |
| WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, |
| INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
| (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR |
| SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
| STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING |
| IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| POSSIBILITY OF SUCH DAMAGE. */ |
| |
| #include "config.h" |
| |
| #include <errno.h> |
| #include <stdlib.h> |
| #include <sys/types.h> |
| |
| #include "backtrace.h" |
| #include "internal.h" |
| |
| /* Allocation routines to use on systems that do not support anonymous |
| mmap. This implementation just uses malloc, which means that the |
| backtrace functions may not be safely invoked from a signal |
| handler. */ |
| |
| /* Allocate memory like malloc. If ERROR_CALLBACK is NULL, don't |
| report an error. */ |
| |
| void * |
| backtrace_alloc (struct backtrace_state *state ATTRIBUTE_UNUSED, |
| size_t size, backtrace_error_callback error_callback, |
| void *data) |
| { |
| void *ret; |
| |
| ret = malloc (size); |
| if (ret == NULL) |
| { |
| if (error_callback) |
| error_callback (data, "malloc", errno); |
| } |
| return ret; |
| } |
| |
| /* Free memory. */ |
| |
| void |
| backtrace_free (struct backtrace_state *state ATTRIBUTE_UNUSED, |
| void *p, size_t size ATTRIBUTE_UNUSED, |
| backtrace_error_callback error_callback ATTRIBUTE_UNUSED, |
| void *data ATTRIBUTE_UNUSED) |
| { |
| free (p); |
| } |
| |
| /* Grow VEC by SIZE bytes. */ |
| |
| void * |
| backtrace_vector_grow (struct backtrace_state *state ATTRIBUTE_UNUSED, |
| size_t size, backtrace_error_callback error_callback, |
| void *data, struct backtrace_vector *vec) |
| { |
| void *ret; |
| |
| if (size > vec->alc) |
| { |
| size_t alc; |
| void *base; |
| |
| if (vec->size == 0) |
| alc = 32 * size; |
| else if (vec->size >= 4096) |
| alc = vec->size + 4096; |
| else |
| alc = 2 * vec->size; |
| |
| if (alc < vec->size + size) |
| alc = vec->size + size; |
| |
| base = realloc (vec->base, alc); |
| if (base == NULL) |
| { |
| error_callback (data, "realloc", errno); |
| return NULL; |
| } |
| |
| vec->base = base; |
| vec->alc = alc - vec->size; |
| } |
| |
| ret = (char *) vec->base + vec->size; |
| vec->size += size; |
| vec->alc -= size; |
| return ret; |
| } |
| |
| /* Finish the current allocation on VEC. */ |
| |
| void * |
| backtrace_vector_finish (struct backtrace_state *state, |
| struct backtrace_vector *vec, |
| backtrace_error_callback error_callback, |
| void *data) |
| { |
| void *ret; |
| |
| /* With this allocator we call realloc in backtrace_vector_grow, |
| which means we can't easily reuse the memory here. So just |
| release it. */ |
| if (!backtrace_vector_release (state, vec, error_callback, data)) |
| return NULL; |
| ret = vec->base; |
| vec->base = NULL; |
| vec->size = 0; |
| vec->alc = 0; |
| return ret; |
| } |
| |
| /* Release any extra space allocated for VEC. */ |
| |
| int |
| backtrace_vector_release (struct backtrace_state *state ATTRIBUTE_UNUSED, |
| struct backtrace_vector *vec, |
| backtrace_error_callback error_callback, |
| void *data) |
| { |
| vec->alc = 0; |
| |
| if (vec->size == 0) |
| { |
| /* As of C17, realloc with size 0 is marked as an obsolescent feature, use |
| free instead. */ |
| free (vec->base); |
| vec->base = NULL; |
| return 1; |
| } |
| |
| vec->base = realloc (vec->base, vec->size); |
| if (vec->base == NULL) |
| { |
| error_callback (data, "realloc", errno); |
| return 0; |
| } |
| |
| return 1; |
| } |