cosmopolitan/third_party/regex/tre-mem.c

152 lines
7.9 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╚──────────────────────────────────────────────────────────────────────────────╝
│ │
│ tre-mem.c - TRE memory allocator │
│ │
│ Copyright (c) 2001-2009 Ville Laurikari <vl@iki.fi> │
│ 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 COPYRIGHT HOLDER 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 COPYRIGHT │
│ HOLDER 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. │
│ │
│──────────────────────────────────────────────────────────────────────────────│
│ │
│ Musl Libc │
│ Copyright © 2005-2014 Rich Felker, et al. │
│ │
│ Permission is hereby granted, free of charge, to any person obtaining │
│ a copy of this software and associated documentation files (the │
│ "Software"), to deal in the Software without restriction, including │
│ without limitation the rights to use, copy, modify, merge, publish, │
│ distribute, sublicense, and/or sell copies of the Software, and to │
│ permit persons to whom the Software is furnished to do so, subject to │
│ the following conditions: │
│ │
│ The above copyright notice and this permission notice shall be │
│ included in all copies or substantial portions of the Software. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, │
│ EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF │
│ MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. │
│ IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY │
│ CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, │
│ TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE │
│ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. │
│ │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "third_party/regex/tre.inc"
/*
This memory allocator is for allocating small memory blocks efficiently
in terms of memory overhead and execution speed. The allocated blocks
cannot be freed individually, only all at once. There can be multiple
allocators, though.
*/
/*
This memory allocator is for allocating small memory blocks efficiently
in terms of memory overhead and execution speed. The allocated blocks
cannot be freed individually, only all at once. There can be multiple
allocators, though.
*/
/* Returns a new memory allocator or NULL if out of memory. */
tre_mem_t tre_mem_new_impl(int provided, void *provided_block) {
tre_mem_t mem;
if (provided) {
mem = provided_block;
memset(mem, 0, sizeof(*mem));
} else
mem = calloc(1, sizeof(*mem));
if (mem == NULL) return NULL;
return mem;
}
/* Frees the memory allocator and all memory allocated with it. */
void tre_mem_destroy(tre_mem_t mem) {
tre_list_t *tmp, *l = mem->blocks;
while (l != NULL) {
free(l->data), l->data = NULL;
tmp = l->next;
free(l), l = tmp;
}
free(mem), mem = NULL;
}
/* Allocates a block of `size' bytes from `mem'. Returns a pointer to the
allocated block or NULL if an underlying malloc() failed. */
void *tre_mem_alloc_impl(tre_mem_t mem, int provided, void *provided_block,
int zero, size_t size) {
void *ptr;
if (mem->failed) {
return NULL;
}
if (mem->n < size) {
/* We need more memory than is available in the current block.
Allocate a new block. */
tre_list_t *l;
if (provided) {
if (provided_block == NULL) {
mem->failed = 1;
return NULL;
}
mem->ptr = provided_block;
mem->n = TRE_MEM_BLOCK_SIZE;
} else {
int block_size;
if (size * 8 > TRE_MEM_BLOCK_SIZE)
block_size = size * 8;
else
block_size = TRE_MEM_BLOCK_SIZE;
l = malloc(sizeof(*l));
if (l == NULL) {
mem->failed = 1;
return NULL;
}
l->data = malloc(block_size);
if (l->data == NULL) {
free(l), l = NULL;
mem->failed = 1;
return NULL;
}
l->next = NULL;
if (mem->current != NULL) mem->current->next = l;
if (mem->blocks == NULL) mem->blocks = l;
mem->current = l;
mem->ptr = l->data;
mem->n = block_size;
}
}
/* Make sure the next pointer will be aligned. */
size += ALIGN(mem->ptr + size, long);
/* Allocate from current block. */
ptr = mem->ptr;
mem->ptr += size;
mem->n -= size;
/* Set to zero if needed. */
if (zero) memset(ptr, 0, size);
return ptr;
}