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Diffstat (limited to 'Modules/_decimal/libmpdec/memory.c')
-rw-r--r-- | Modules/_decimal/libmpdec/memory.c | 292 |
1 files changed, 292 insertions, 0 deletions
diff --git a/Modules/_decimal/libmpdec/memory.c b/Modules/_decimal/libmpdec/memory.c new file mode 100644 index 0000000..bf6350f --- /dev/null +++ b/Modules/_decimal/libmpdec/memory.c @@ -0,0 +1,292 @@ +/* + * Copyright (c) 2008-2012 Stefan Krah. All rights reserved. + * + * 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. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "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 OR CONTRIBUTORS 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 "mpdecimal.h" +#include <stdio.h> +#include <stdlib.h> +#include "typearith.h" +#include "memory.h" + + +/* Guaranteed minimum allocation for a coefficient. May be changed once + at program start using mpd_setminalloc(). */ +mpd_ssize_t MPD_MINALLOC = MPD_MINALLOC_MIN; + +/* Custom allocation and free functions */ +void *(* mpd_mallocfunc)(size_t size) = malloc; +void *(* mpd_reallocfunc)(void *ptr, size_t size) = realloc; +void *(* mpd_callocfunc)(size_t nmemb, size_t size) = calloc; +void (* mpd_free)(void *ptr) = free; + + +/* emulate calloc if it is not available */ +void * +mpd_callocfunc_em(size_t nmemb, size_t size) +{ + void *ptr; + size_t req; + mpd_size_t overflow; + +#if MPD_SIZE_MAX < SIZE_MAX + /* full_coverage test only */ + if (nmemb > MPD_SIZE_MAX || size > MPD_SIZE_MAX) { + return NULL; + } +#endif + + req = mul_size_t_overflow((mpd_size_t)nmemb, (mpd_size_t)size, + &overflow); + if (overflow) { + return NULL; + } + + ptr = mpd_mallocfunc(req); + if (ptr == NULL) { + return NULL; + } + /* used on uint32_t or uint64_t */ + memset(ptr, 0, req); + + return ptr; +} + + +/* malloc with overflow checking */ +void * +mpd_alloc(mpd_size_t nmemb, mpd_size_t size) +{ + mpd_size_t req, overflow; + + req = mul_size_t_overflow(nmemb, size, &overflow); + if (overflow) { + return NULL; + } + + return mpd_mallocfunc(req); +} + +/* calloc with overflow checking */ +void * +mpd_calloc(mpd_size_t nmemb, mpd_size_t size) +{ + mpd_size_t overflow; + + (void)mul_size_t_overflow(nmemb, size, &overflow); + if (overflow) { + return NULL; + } + + return mpd_callocfunc(nmemb, size); +} + +/* realloc with overflow checking */ +void * +mpd_realloc(void *ptr, mpd_size_t nmemb, mpd_size_t size, uint8_t *err) +{ + void *new; + mpd_size_t req, overflow; + + req = mul_size_t_overflow(nmemb, size, &overflow); + if (overflow) { + *err = 1; + return ptr; + } + + new = mpd_reallocfunc(ptr, req); + if (new == NULL) { + *err = 1; + return ptr; + } + + return new; +} + +/* struct hack malloc with overflow checking */ +void * +mpd_sh_alloc(mpd_size_t struct_size, mpd_size_t nmemb, mpd_size_t size) +{ + mpd_size_t req, overflow; + + req = mul_size_t_overflow(nmemb, size, &overflow); + if (overflow) { + return NULL; + } + + req = add_size_t_overflow(req, struct_size, &overflow); + if (overflow) { + return NULL; + } + + return mpd_mallocfunc(req); +} + + +/* Allocate a new decimal with a coefficient of length 'nwords'. In case + of an error the return value is NULL. */ +mpd_t * +mpd_qnew_size(mpd_ssize_t nwords) +{ + mpd_t *result; + + nwords = (nwords < MPD_MINALLOC) ? MPD_MINALLOC : nwords; + + result = mpd_alloc(1, sizeof *result); + if (result == NULL) { + return NULL; + } + + result->data = mpd_alloc(nwords, sizeof *result->data); + if (result->data == NULL) { + mpd_free(result); + return NULL; + } + + result->flags = 0; + result->exp = 0; + result->digits = 0; + result->len = 0; + result->alloc = nwords; + + return result; +} + +/* Allocate a new decimal with a coefficient of length MPD_MINALLOC. + In case of an error the return value is NULL. */ +mpd_t * +mpd_qnew(void) +{ + return mpd_qnew_size(MPD_MINALLOC); +} + +/* Allocate new decimal. Caller can check for NULL or MPD_Malloc_error. + Raises on error. */ +mpd_t * +mpd_new(mpd_context_t *ctx) +{ + mpd_t *result; + + result = mpd_qnew(); + if (result == NULL) { + mpd_addstatus_raise(ctx, MPD_Malloc_error); + } + return result; +} + +/* + * Input: 'result' is a static mpd_t with a static coefficient. + * Assumption: 'nwords' >= result->alloc. + * + * Resize the static coefficient to a larger dynamic one and copy the + * existing data. If successful, the value of 'result' is unchanged. + * Otherwise, set 'result' to NaN and update 'status' with MPD_Malloc_error. + */ +int +mpd_switch_to_dyn(mpd_t *result, mpd_ssize_t nwords, uint32_t *status) +{ + mpd_uint_t *p = result->data; + + assert(nwords >= result->alloc); + + result->data = mpd_alloc(nwords, sizeof *result->data); + if (result->data == NULL) { + result->data = p; + mpd_set_qnan(result); + mpd_set_positive(result); + result->exp = result->digits = result->len = 0; + *status |= MPD_Malloc_error; + return 0; + } + + memcpy(result->data, p, result->alloc * (sizeof *result->data)); + result->alloc = nwords; + mpd_set_dynamic_data(result); + return 1; +} + +/* + * Input: 'result' is a static mpd_t with a static coefficient. + * + * Convert the coefficient to a dynamic one that is initialized to zero. If + * malloc fails, set 'result' to NaN and update 'status' with MPD_Malloc_error. + */ +int +mpd_switch_to_dyn_zero(mpd_t *result, mpd_ssize_t nwords, uint32_t *status) +{ + mpd_uint_t *p = result->data; + + result->data = mpd_calloc(nwords, sizeof *result->data); + if (result->data == NULL) { + result->data = p; + mpd_set_qnan(result); + mpd_set_positive(result); + result->exp = result->digits = result->len = 0; + *status |= MPD_Malloc_error; + return 0; + } + + result->alloc = nwords; + mpd_set_dynamic_data(result); + + return 1; +} + +/* + * Input: 'result' is a static or a dynamic mpd_t with a dynamic coefficient. + * Resize the coefficient to length 'nwords': + * Case nwords > result->alloc: + * If realloc is successful: + * 'result' has a larger coefficient but the same value. Return 1. + * Otherwise: + * Set 'result' to NaN, update status with MPD_Malloc_error and return 0. + * Case nwords < result->alloc: + * If realloc is successful: + * 'result' has a smaller coefficient. result->len is undefined. Return 1. + * Otherwise (unlikely): + * 'result' is unchanged. Reuse the now oversized coefficient. Return 1. + */ +int +mpd_realloc_dyn(mpd_t *result, mpd_ssize_t nwords, uint32_t *status) +{ + uint8_t err = 0; + + result->data = mpd_realloc(result->data, nwords, sizeof *result->data, &err); + if (!err) { + result->alloc = nwords; + } + else if (nwords > result->alloc) { + mpd_set_qnan(result); + mpd_set_positive(result); + result->exp = result->digits = result->len = 0; + *status |= MPD_Malloc_error; + return 0; + } + + return 1; +} + + |