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/*
* Copyright © 2010 Intel Corporation
*
* 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 (including the next
* paragraph) 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 <assert.h>
#include <stdlib.h>
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
#include <stdint.h>
/* Some versions of MinGW are missing _vscprintf's declaration, although they
* still provide the symbol in the import library. */
#ifdef __MINGW32__
_CRTIMP int _vscprintf(const char *format, va_list argptr);
#endif
#include "ralloc.h"
#ifndef va_copy
#ifdef __va_copy
#define va_copy(dest, src) __va_copy((dest), (src))
#else
#define va_copy(dest, src) (dest) = (src)
#endif
#endif
#define CANARY 0x5A1106
/* Align the header's size so that ralloc() allocations will return with the
* same alignment as a libc malloc would have (8 on 32-bit GLIBC, 16 on
* 64-bit), avoiding performance penalities on x86 and alignment faults on
* ARM.
*/
struct
#ifdef _MSC_VER
#if _WIN64
__declspec(align(16))
#else
__declspec(align(8))
#endif
#elif defined(__LP64__)
__attribute__((aligned(16)))
#else
__attribute__((aligned(8)))
#endif
ralloc_header
{
#ifndef NDEBUG
/* A canary value used to determine whether a pointer is ralloc'd. */
unsigned canary;
#endif
struct ralloc_header *parent;
/* The first child (head of a linked list) */
struct ralloc_header *child;
/* Linked list of siblings */
struct ralloc_header *prev;
struct ralloc_header *next;
void (*destructor)(void *);
};
typedef struct ralloc_header ralloc_header;
static void unlink_block(ralloc_header *info);
static void unsafe_free(ralloc_header *info);
static ralloc_header *
get_header(const void *ptr)
{
ralloc_header *info = (ralloc_header *) (((char *) ptr) -
sizeof(ralloc_header));
assert(info->canary == CANARY);
return info;
}
#define PTR_FROM_HEADER(info) (((char *) info) + sizeof(ralloc_header))
static void
add_child(ralloc_header *parent, ralloc_header *info)
{
if (parent != NULL) {
info->parent = parent;
info->next = parent->child;
parent->child = info;
if (info->next != NULL)
info->next->prev = info;
}
}
void *
ralloc_context(const void *ctx)
{
return ralloc_size(ctx, 0);
}
void *
ralloc_size(const void *ctx, size_t size)
{
void *block = malloc(size + sizeof(ralloc_header));
ralloc_header *info;
ralloc_header *parent;
if (unlikely(block == NULL))
return NULL;
info = (ralloc_header *) block;
/* measurements have shown that calloc is slower (because of
* the multiplication overflow checking?), so clear things
* manually
*/
info->parent = NULL;
info->child = NULL;
info->prev = NULL;
info->next = NULL;
info->destructor = NULL;
parent = ctx != NULL ? get_header(ctx) : NULL;
add_child(parent, info);
#ifndef NDEBUG
info->canary = CANARY;
#endif
return PTR_FROM_HEADER(info);
}
void *
rzalloc_size(const void *ctx, size_t size)
{
void *ptr = ralloc_size(ctx, size);
if (likely(ptr))
memset(ptr, 0, size);
return ptr;
}
/* helper function - assumes ptr != NULL */
static void *
resize(void *ptr, size_t size)
{
ralloc_header *child, *old, *info;
old = get_header(ptr);
info = realloc(old, size + sizeof(ralloc_header));
if (info == NULL)
return NULL;
/* Update parent and sibling's links to the reallocated node. */
if (info != old && info->parent != NULL) {
if (info->parent->child == old)
info->parent->child = info;
if (info->prev != NULL)
info->prev->next = info;
if (info->next != NULL)
info->next->prev = info;
}
/* Update child->parent links for all children */
for (child = info->child; child != NULL; child = child->next)
child->parent = info;
return PTR_FROM_HEADER(info);
}
void *
reralloc_size(const void *ctx, void *ptr, size_t size)
{
if (unlikely(ptr == NULL))
return ralloc_size(ctx, size);
assert(ralloc_parent(ptr) == ctx);
return resize(ptr, size);
}
void *
rerzalloc_size(const void *ctx, void *ptr, size_t old_size, size_t new_size)
{
if (unlikely(ptr == NULL))
return rzalloc_size(ctx, new_size);
assert(ralloc_parent(ptr) == ctx);
ptr = resize(ptr, new_size);
if (new_size > old_size)
memset((char *)ptr + old_size, 0, new_size - old_size);
return ptr;
}
void *
ralloc_array_size(const void *ctx, size_t size, unsigned count)
{
if (count > SIZE_MAX/size)
return NULL;
return ralloc_size(ctx, size * count);
}
void *
rzalloc_array_size(const void *ctx, size_t size, unsigned count)
{
if (count > SIZE_MAX/size)
return NULL;
return rzalloc_size(ctx, size * count);
}
void *
reralloc_array_size(const void *ctx, void *ptr, size_t size, unsigned count)
{
if (count > SIZE_MAX/size)
return NULL;
return reralloc_size(ctx, ptr, size * count);
}
void *
rerzalloc_array_size(const void *ctx, void *ptr, size_t size,
unsigned old_count, unsigned new_count)
{
if (new_count > SIZE_MAX/size)
return NULL;
return rerzalloc_size(ctx, ptr, size * old_count, size * new_count);
}
void
ralloc_free(void *ptr)
{
ralloc_header *info;
if (ptr == NULL)
return;
info = get_header(ptr);
unlink_block(info);
unsafe_free(info);
}
static void
unlink_block(ralloc_header *info)
{
/* Unlink from parent & siblings */
if (info->parent != NULL) {
if (info->parent->child == info)
info->parent->child = info->next;
if (info->prev != NULL)
info->prev->next = info->next;
if (info->next != NULL)
info->next->prev = info->prev;
}
info->parent = NULL;
info->prev = NULL;
info->next = NULL;
}
static void
unsafe_free(ralloc_header *info)
{
/* Recursively free any children...don't waste time unlinking them. */
ralloc_header *temp;
while (info->child != NULL) {
temp = info->child;
info->child = temp->next;
unsafe_free(temp);
}
/* Free the block itself. Call the destructor first, if any. */
if (info->destructor != NULL)
info->destructor(PTR_FROM_HEADER(info));
free(info);
}
void
ralloc_steal(const void *new_ctx, void *ptr)
{
ralloc_header *info, *parent;
if (unlikely(ptr == NULL))
return;
info = get_header(ptr);
parent = new_ctx ? get_header(new_ctx) : NULL;
unlink_block(info);
add_child(parent, info);
}
void
ralloc_adopt(const void *new_ctx, void *old_ctx)
{
ralloc_header *new_info, *old_info, *child;
if (unlikely(old_ctx == NULL))
return;
old_info = get_header(old_ctx);
new_info = get_header(new_ctx);
/* If there are no children, bail. */
if (unlikely(old_info->child == NULL))
return;
/* Set all the children's parent to new_ctx; get a pointer to the last child. */
for (child = old_info->child; child->next != NULL; child = child->next) {
child->parent = new_info;
}
child->parent = new_info;
/* Connect the two lists together; parent them to new_ctx; make old_ctx empty. */
child->next = new_info->child;
if (child->next)
child->next->prev = child;
new_info->child = old_info->child;
old_info->child = NULL;
}
void *
ralloc_parent(const void *ptr)
{
ralloc_header *info;
if (unlikely(ptr == NULL))
return NULL;
info = get_header(ptr);
return info->parent ? PTR_FROM_HEADER(info->parent) : NULL;
}
void
ralloc_set_destructor(const void *ptr, void(*destructor)(void *))
{
ralloc_header *info = get_header(ptr);
info->destructor = destructor;
}
char *
ralloc_strdup(const void *ctx, const char *str)
{
size_t n;
char *ptr;
if (unlikely(str == NULL))
return NULL;
n = strlen(str);
ptr = ralloc_array(ctx, char, n + 1);
memcpy(ptr, str, n);
ptr[n] = '\0';
return ptr;
}
char *
ralloc_strndup(const void *ctx, const char *str, size_t max)
{
size_t n;
char *ptr;
if (unlikely(str == NULL))
return NULL;
n = strnlen(str, max);
ptr = ralloc_array(ctx, char, n + 1);
memcpy(ptr, str, n);
ptr[n] = '\0';
return ptr;
}
/* helper routine for strcat/strncat - n is the exact amount to copy */
static bool
cat(char **dest, const char *str, size_t n)
{
char *both;
size_t existing_length;
assert(dest != NULL && *dest != NULL);
existing_length = strlen(*dest);
both = resize(*dest, existing_length + n + 1);
if (unlikely(both == NULL))
return false;
memcpy(both + existing_length, str, n);
both[existing_length + n] = '\0';
*dest = both;
return true;
}
bool
ralloc_strcat(char **dest, const char *str)
{
return cat(dest, str, strlen(str));
}
bool
ralloc_strncat(char **dest, const char *str, size_t n)
{
return cat(dest, str, strnlen(str, n));
}
bool
ralloc_str_append(char **dest, const char *str,
size_t existing_length, size_t str_size)
{
char *both;
assert(dest != NULL && *dest != NULL);
both = resize(*dest, existing_length + str_size + 1);
if (unlikely(both == NULL))
return false;
memcpy(both + existing_length, str, str_size);
both[existing_length + str_size] = '\0';
*dest = both;
return true;
}
char *
ralloc_asprintf(const void *ctx, const char *fmt, ...)
{
char *ptr;
va_list args;
va_start(args, fmt);
ptr = ralloc_vasprintf(ctx, fmt, args);
va_end(args);
return ptr;
}
size_t
printf_length(const char *fmt, va_list untouched_args)
{
int size;
char junk;
/* Make a copy of the va_list so the original caller can still use it */
va_list args;
va_copy(args, untouched_args);
#ifdef _WIN32
/* We need to use _vcsprintf to calculate the size as vsnprintf returns -1
* if the number of characters to write is greater than count.
*/
size = _vscprintf(fmt, args);
(void)junk;
#else
size = vsnprintf(&junk, 1, fmt, args);
#endif
assert(size >= 0);
va_end(args);
return size;
}
char *
ralloc_vasprintf(const void *ctx, const char *fmt, va_list args)
{
size_t size = printf_length(fmt, args) + 1;
char *ptr = ralloc_size(ctx, size);
if (ptr != NULL)
vsnprintf(ptr, size, fmt, args);
return ptr;
}
bool
ralloc_asprintf_append(char **str, const char *fmt, ...)
{
bool success;
va_list args;
va_start(args, fmt);
success = ralloc_vasprintf_append(str, fmt, args);
va_end(args);
return success;
}
bool
ralloc_vasprintf_append(char **str, const char *fmt, va_list args)
{
size_t existing_length;
assert(str != NULL);
existing_length = *str ? strlen(*str) : 0;
return ralloc_vasprintf_rewrite_tail(str, &existing_length, fmt, args);
}
bool
ralloc_asprintf_rewrite_tail(char **str, size_t *start, const char *fmt, ...)
{
bool success;
va_list args;
va_start(args, fmt);
success = ralloc_vasprintf_rewrite_tail(str, start, fmt, args);
va_end(args);
return success;
}
bool
ralloc_vasprintf_rewrite_tail(char **str, size_t *start, const char *fmt,
va_list args)
{
size_t new_length;
char *ptr;
assert(str != NULL);
if (unlikely(*str == NULL)) {
// Assuming a NULL context is probably bad, but it's expected behavior.
*str = ralloc_vasprintf(NULL, fmt, args);
*start = strlen(*str);
return true;
}
new_length = printf_length(fmt, args);
ptr = resize(*str, *start + new_length + 1);
if (unlikely(ptr == NULL))
return false;
vsnprintf(ptr + *start, new_length + 1, fmt, args);
*str = ptr;
*start += new_length;
return true;
}
/***************************************************************************
* Linear allocator for short-lived allocations.
***************************************************************************
*
* The allocator consists of a parent node (2K buffer), which requires
* a ralloc parent, and child nodes (allocations). Child nodes can't be freed
* directly, because the parent doesn't track them. You have to release
* the parent node in order to release all its children.
*
* The allocator uses a fixed-sized buffer with a monotonically increasing
* offset after each allocation. If the buffer is all used, another buffer
* is allocated, sharing the same ralloc parent, so all buffers are at
* the same level in the ralloc hierarchy.
*
* The linear parent node is always the first buffer and keeps track of all
* other buffers.
*/
#define MIN_LINEAR_BUFSIZE 2048
#define SUBALLOC_ALIGNMENT 8
#define LMAGIC 0x87b9c7d3
struct
#ifdef _MSC_VER
__declspec(align(8))
#elif defined(__LP64__)
__attribute__((aligned(16)))
#else
__attribute__((aligned(8)))
#endif
linear_header {
#ifndef NDEBUG
unsigned magic; /* for debugging */
#endif
unsigned offset; /* points to the first unused byte in the buffer */
unsigned size; /* size of the buffer */
void *ralloc_parent; /* new buffers will use this */
struct linear_header *next; /* next buffer if we have more */
struct linear_header *latest; /* the only buffer that has free space */
/* After this structure, the buffer begins.
* Each suballocation consists of linear_size_chunk as its header followed
* by the suballocation, so it goes:
*
* - linear_size_chunk
* - allocated space
* - linear_size_chunk
* - allocated space
* etc.
*
* linear_size_chunk is only needed by linear_realloc.
*/
};
struct linear_size_chunk {
unsigned size; /* for realloc */
unsigned _padding;
};
typedef struct linear_header linear_header;
typedef struct linear_size_chunk linear_size_chunk;
#define LINEAR_PARENT_TO_HEADER(parent) \
(linear_header*) \
((char*)(parent) - sizeof(linear_size_chunk) - sizeof(linear_header))
/* Allocate the linear buffer with its header. */
static linear_header *
create_linear_node(void *ralloc_ctx, unsigned min_size)
{
linear_header *node;
min_size += sizeof(linear_size_chunk);
if (likely(min_size < MIN_LINEAR_BUFSIZE))
min_size = MIN_LINEAR_BUFSIZE;
node = ralloc_size(ralloc_ctx, sizeof(linear_header) + min_size);
if (unlikely(!node))
return NULL;
#ifndef NDEBUG
node->magic = LMAGIC;
#endif
node->offset = 0;
node->size = min_size;
node->ralloc_parent = ralloc_ctx;
node->next = NULL;
node->latest = node;
return node;
}
void *
linear_alloc_child(void *parent, unsigned size)
{
linear_header *first = LINEAR_PARENT_TO_HEADER(parent);
linear_header *latest = first->latest;
linear_header *new_node;
linear_size_chunk *ptr;
unsigned full_size;
assert(first->magic == LMAGIC);
assert(!latest->next);
size = ALIGN_POT(size, SUBALLOC_ALIGNMENT);
full_size = sizeof(linear_size_chunk) + size;
if (unlikely(latest->offset + full_size > latest->size)) {
/* allocate a new node */
new_node = create_linear_node(latest->ralloc_parent, size);
if (unlikely(!new_node))
return NULL;
first->latest = new_node;
latest->latest = new_node;
latest->next = new_node;
latest = new_node;
}
ptr = (linear_size_chunk *)((char*)&latest[1] + latest->offset);
ptr->size = size;
latest->offset += full_size;
assert((uintptr_t)&ptr[1] % SUBALLOC_ALIGNMENT == 0);
return &ptr[1];
}
void *
linear_alloc_parent(void *ralloc_ctx, unsigned size)
{
linear_header *node;
if (unlikely(!ralloc_ctx))
return NULL;
size = ALIGN_POT(size, SUBALLOC_ALIGNMENT);
node = create_linear_node(ralloc_ctx, size);
if (unlikely(!node))
return NULL;
return linear_alloc_child((char*)node +
sizeof(linear_header) +
sizeof(linear_size_chunk), size);
}
void *
linear_zalloc_child(void *parent, unsigned size)
{
void *ptr = linear_alloc_child(parent, size);
if (likely(ptr))
memset(ptr, 0, size);
return ptr;
}
void *
linear_zalloc_parent(void *parent, unsigned size)
{
void *ptr = linear_alloc_parent(parent, size);
if (likely(ptr))
memset(ptr, 0, size);
return ptr;
}
void
linear_free_parent(void *ptr)
{
linear_header *node;
if (unlikely(!ptr))
return;
node = LINEAR_PARENT_TO_HEADER(ptr);
assert(node->magic == LMAGIC);
while (node) {
void *ptr = node;
node = node->next;
ralloc_free(ptr);
}
}
void
ralloc_steal_linear_parent(void *new_ralloc_ctx, void *ptr)
{
linear_header *node;
if (unlikely(!ptr))
return;
node = LINEAR_PARENT_TO_HEADER(ptr);
assert(node->magic == LMAGIC);
while (node) {
ralloc_steal(new_ralloc_ctx, node);
node->ralloc_parent = new_ralloc_ctx;
node = node->next;
}
}
void *
ralloc_parent_of_linear_parent(void *ptr)
{
linear_header *node = LINEAR_PARENT_TO_HEADER(ptr);
assert(node->magic == LMAGIC);
return node->ralloc_parent;
}
void *
linear_realloc(void *parent, void *old, unsigned new_size)
{
unsigned old_size = 0;
ralloc_header *new_ptr;
new_ptr = linear_alloc_child(parent, new_size);
if (unlikely(!old))
return new_ptr;
old_size = ((linear_size_chunk*)old)[-1].size;
if (likely(new_ptr && old_size))
memcpy(new_ptr, old, MIN2(old_size, new_size));
return new_ptr;
}
/* All code below is pretty much copied from ralloc and only the alloc
* calls are different.
*/
char *
linear_strdup(void *parent, const char *str)
{
unsigned n;
char *ptr;
if (unlikely(!str))
return NULL;
n = strlen(str);
ptr = linear_alloc_child(parent, n + 1);
if (unlikely(!ptr))
return NULL;
memcpy(ptr, str, n);
ptr[n] = '\0';
return ptr;
}
char *
linear_asprintf(void *parent, const char *fmt, ...)
{
char *ptr;
va_list args;
va_start(args, fmt);
ptr = linear_vasprintf(parent, fmt, args);
va_end(args);
return ptr;
}
char *
linear_vasprintf(void *parent, const char *fmt, va_list args)
{
unsigned size = printf_length(fmt, args) + 1;
char *ptr = linear_alloc_child(parent, size);
if (ptr != NULL)
vsnprintf(ptr, size, fmt, args);
return ptr;
}
bool
linear_asprintf_append(void *parent, char **str, const char *fmt, ...)
{
bool success;
va_list args;
va_start(args, fmt);
success = linear_vasprintf_append(parent, str, fmt, args);
va_end(args);
return success;
}
bool
linear_vasprintf_append(void *parent, char **str, const char *fmt, va_list args)
{
size_t existing_length;
assert(str != NULL);
existing_length = *str ? strlen(*str) : 0;
return linear_vasprintf_rewrite_tail(parent, str, &existing_length, fmt, args);
}
bool
linear_asprintf_rewrite_tail(void *parent, char **str, size_t *start,
const char *fmt, ...)
{
bool success;
va_list args;
va_start(args, fmt);
success = linear_vasprintf_rewrite_tail(parent, str, start, fmt, args);
va_end(args);
return success;
}
bool
linear_vasprintf_rewrite_tail(void *parent, char **str, size_t *start,
const char *fmt, va_list args)
{
size_t new_length;
char *ptr;
assert(str != NULL);
if (unlikely(*str == NULL)) {
*str = linear_vasprintf(parent, fmt, args);
*start = strlen(*str);
return true;
}
new_length = printf_length(fmt, args);
ptr = linear_realloc(parent, *str, *start + new_length + 1);
if (unlikely(ptr == NULL))
return false;
vsnprintf(ptr + *start, new_length + 1, fmt, args);
*str = ptr;
*start += new_length;
return true;
}
/* helper routine for strcat/strncat - n is the exact amount to copy */
static bool
linear_cat(void *parent, char **dest, const char *str, unsigned n)
{
char *both;
unsigned existing_length;
assert(dest != NULL && *dest != NULL);
existing_length = strlen(*dest);
both = linear_realloc(parent, *dest, existing_length + n + 1);
if (unlikely(both == NULL))
return false;
memcpy(both + existing_length, str, n);
both[existing_length + n] = '\0';
*dest = both;
return true;
}
bool
linear_strcat(void *parent, char **dest, const char *str)
{
return linear_cat(parent, dest, str, strlen(str));
}