path: root/contrib/libs/pcre/sljit/sljitUtils.c

/* 
 *    Stack-less Just-In-Time compiler 
 * 
 *    Copyright Zoltan Herczeg (hzmester@freemail.hu). 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(S) 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(S) 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. 
 */ 
 
/* ------------------------------------------------------------------------ */ 
/*  Locks                                                                   */ 
/* ------------------------------------------------------------------------ */ 
 
#if (defined SLJIT_EXECUTABLE_ALLOCATOR && SLJIT_EXECUTABLE_ALLOCATOR) || (defined SLJIT_UTIL_GLOBAL_LOCK && SLJIT_UTIL_GLOBAL_LOCK) 
 
#if (defined SLJIT_SINGLE_THREADED && SLJIT_SINGLE_THREADED) 
 
#if (defined SLJIT_EXECUTABLE_ALLOCATOR && SLJIT_EXECUTABLE_ALLOCATOR) 
 
static SLJIT_INLINE void allocator_grab_lock(void) 
{ 
	/* Always successful. */ 
} 
 
static SLJIT_INLINE void allocator_release_lock(void) 
{ 
	/* Always successful. */ 
} 
 
#endif /* SLJIT_EXECUTABLE_ALLOCATOR */ 
 
#if (defined SLJIT_UTIL_GLOBAL_LOCK && SLJIT_UTIL_GLOBAL_LOCK) 
 
SLJIT_API_FUNC_ATTRIBUTE void SLJIT_FUNC sljit_grab_lock(void) 
{ 
	/* Always successful. */ 
} 
 
SLJIT_API_FUNC_ATTRIBUTE void SLJIT_FUNC sljit_release_lock(void) 
{ 
	/* Always successful. */ 
} 
 
#endif /* SLJIT_UTIL_GLOBAL_LOCK */ 
 
#elif defined(_WIN32) /* SLJIT_SINGLE_THREADED */ 
 
#include "windows.h" 
 
#if (defined SLJIT_EXECUTABLE_ALLOCATOR && SLJIT_EXECUTABLE_ALLOCATOR) 
 
static HANDLE allocator_mutex = 0; 
 
static SLJIT_INLINE void allocator_grab_lock(void) 
{ 
	/* No idea what to do if an error occures. Static mutexes should never fail... */ 
	if (!allocator_mutex) 
		allocator_mutex = CreateMutex(NULL, TRUE, NULL); 
	else 
		WaitForSingleObject(allocator_mutex, INFINITE); 
} 
 
static SLJIT_INLINE void allocator_release_lock(void) 
{ 
	ReleaseMutex(allocator_mutex); 
} 
 
#endif /* SLJIT_EXECUTABLE_ALLOCATOR */ 
 
#if (defined SLJIT_UTIL_GLOBAL_LOCK && SLJIT_UTIL_GLOBAL_LOCK) 
 
static HANDLE global_mutex = 0; 
 
SLJIT_API_FUNC_ATTRIBUTE void SLJIT_FUNC sljit_grab_lock(void) 
{ 
	/* No idea what to do if an error occures. Static mutexes should never fail... */ 
	if (!global_mutex) 
		global_mutex = CreateMutex(NULL, TRUE, NULL); 
	else 
		WaitForSingleObject(global_mutex, INFINITE); 
} 
 
SLJIT_API_FUNC_ATTRIBUTE void SLJIT_FUNC sljit_release_lock(void) 
{ 
	ReleaseMutex(global_mutex); 
} 
 
#endif /* SLJIT_UTIL_GLOBAL_LOCK */ 
 
#else /* _WIN32 */ 
 
#if (defined SLJIT_EXECUTABLE_ALLOCATOR && SLJIT_EXECUTABLE_ALLOCATOR) 
 
#include <pthread.h> 
 
static pthread_mutex_t allocator_mutex = PTHREAD_MUTEX_INITIALIZER; 
 
static SLJIT_INLINE void allocator_grab_lock(void) 
{ 
	pthread_mutex_lock(&allocator_mutex); 
} 
 
static SLJIT_INLINE void allocator_release_lock(void) 
{ 
	pthread_mutex_unlock(&allocator_mutex); 
} 
 
#endif /* SLJIT_EXECUTABLE_ALLOCATOR */ 
 
#if (defined SLJIT_UTIL_GLOBAL_LOCK && SLJIT_UTIL_GLOBAL_LOCK) 
 
#include <pthread.h> 
 
static pthread_mutex_t global_mutex = PTHREAD_MUTEX_INITIALIZER; 
 
SLJIT_API_FUNC_ATTRIBUTE void SLJIT_FUNC sljit_grab_lock(void) 
{ 
	pthread_mutex_lock(&global_mutex); 
} 
 
SLJIT_API_FUNC_ATTRIBUTE void SLJIT_FUNC sljit_release_lock(void) 
{ 
	pthread_mutex_unlock(&global_mutex); 
} 
 
#endif /* SLJIT_UTIL_GLOBAL_LOCK */ 
 
#endif /* _WIN32 */ 
 
/* ------------------------------------------------------------------------ */ 
/*  Stack                                                                   */ 
/* ------------------------------------------------------------------------ */ 
 
#if (defined SLJIT_UTIL_STACK && SLJIT_UTIL_STACK) || (defined SLJIT_EXECUTABLE_ALLOCATOR && SLJIT_EXECUTABLE_ALLOCATOR) 
 
#ifdef _WIN32 
#include "windows.h" 
#else 
/* Provides mmap function. */ 
#include <sys/types.h> 
#include <sys/mman.h> 
#ifndef MAP_ANON 
#ifdef MAP_ANONYMOUS 
#define MAP_ANON MAP_ANONYMOUS 
#endif 
#endif 
/* For detecting the page size. */ 
#include <unistd.h> 
 
#ifndef MAP_ANON 
 
#include <fcntl.h> 
 
/* Some old systems does not have MAP_ANON. */ 
static sljit_s32 dev_zero = -1; 
 
#if (defined SLJIT_SINGLE_THREADED && SLJIT_SINGLE_THREADED) 
 
static SLJIT_INLINE sljit_s32 open_dev_zero(void) 
{ 
	dev_zero = open("/dev/zero", O_RDWR); 
	return dev_zero < 0; 
} 
 
#else /* SLJIT_SINGLE_THREADED */ 
 
#include <pthread.h> 
 
static pthread_mutex_t dev_zero_mutex = PTHREAD_MUTEX_INITIALIZER; 
 
static SLJIT_INLINE sljit_s32 open_dev_zero(void) 
{ 
	pthread_mutex_lock(&dev_zero_mutex); 
	/* The dev_zero might be initialized by another thread during the waiting. */ 
	if (dev_zero < 0) { 
		dev_zero = open("/dev/zero", O_RDWR); 
	} 
	pthread_mutex_unlock(&dev_zero_mutex); 
	return dev_zero < 0; 
} 
 
#endif /* SLJIT_SINGLE_THREADED */ 
 
#endif 
 
#endif 
 
#endif /* SLJIT_UTIL_STACK || SLJIT_EXECUTABLE_ALLOCATOR */ 
 
#if (defined SLJIT_UTIL_STACK && SLJIT_UTIL_STACK) 
 
/* Planning to make it even more clever in the future. */ 
static sljit_sw sljit_page_align = 0; 
 
SLJIT_API_FUNC_ATTRIBUTE struct sljit_stack* SLJIT_FUNC sljit_allocate_stack(sljit_uw start_size, sljit_uw max_size, void *allocator_data) 
{ 
	struct sljit_stack *stack; 
	void *ptr; 
#ifdef _WIN32 
	SYSTEM_INFO si; 
#endif 
 
	SLJIT_UNUSED_ARG(allocator_data); 
	if (start_size > max_size || start_size < 1) 
		return NULL; 
 
#ifdef _WIN32 
	if (!sljit_page_align) { 
		GetSystemInfo(&si); 
		sljit_page_align = si.dwPageSize - 1; 
	} 
#else 
	if (!sljit_page_align) { 
		sljit_page_align = sysconf(_SC_PAGESIZE); 
		/* Should never happen. */ 
		if (sljit_page_align < 0) 
			sljit_page_align = 4096; 
		sljit_page_align--; 
	} 
#endif 
 
	stack = (struct sljit_stack*)SLJIT_MALLOC(sizeof(struct sljit_stack), allocator_data); 
	if (!stack) 
		return NULL; 
 
	/* Align max_size. */ 
	max_size = (max_size + sljit_page_align) & ~sljit_page_align; 
 
#ifdef _WIN32 
	ptr = VirtualAlloc(NULL, max_size, MEM_RESERVE, PAGE_READWRITE); 
	if (!ptr) { 
		SLJIT_FREE(stack, allocator_data); 
		return NULL; 
	} 
 
	stack->min_start = (sljit_u8 *)ptr; 
	stack->end = stack->min_start + max_size; 
	stack->start = stack->end; 
 
	if (sljit_stack_resize(stack, stack->end - start_size) == NULL) { 
		sljit_free_stack(stack, allocator_data); 
		return NULL; 
	} 
#else 
#ifdef MAP_ANON 
	ptr = mmap(NULL, max_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0); 
#else 
	if (dev_zero < 0) { 
		if (open_dev_zero()) { 
			SLJIT_FREE(stack, allocator_data); 
			return NULL; 
		} 
	} 
	ptr = mmap(NULL, max_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, dev_zero, 0); 
#endif 
	if (ptr == MAP_FAILED) { 
		SLJIT_FREE(stack, allocator_data); 
		return NULL; 
	} 
	stack->min_start = (sljit_u8 *)ptr; 
	stack->end = stack->min_start + max_size; 
	stack->start = stack->end - start_size; 
#endif 
	stack->top = stack->end; 
	return stack; 
} 
 
#undef PAGE_ALIGN 
 
SLJIT_API_FUNC_ATTRIBUTE void SLJIT_FUNC sljit_free_stack(struct sljit_stack *stack, void *allocator_data) 
{ 
	SLJIT_UNUSED_ARG(allocator_data); 
#ifdef _WIN32 
	VirtualFree((void*)stack->min_start, 0, MEM_RELEASE); 
#else 
	munmap((void*)stack->min_start, stack->end - stack->min_start); 
#endif 
	SLJIT_FREE(stack, allocator_data); 
} 
 
SLJIT_API_FUNC_ATTRIBUTE sljit_u8 *SLJIT_FUNC sljit_stack_resize(struct sljit_stack *stack, sljit_u8 *new_start) 
{ 
	sljit_uw aligned_old_start; 
	sljit_uw aligned_new_start; 
 
	if ((new_start < stack->min_start) || (new_start >= stack->end)) 
		return NULL; 
 
#ifdef _WIN32 
	aligned_new_start = (sljit_uw)new_start & ~sljit_page_align; 
	aligned_old_start = ((sljit_uw)stack->start) & ~sljit_page_align; 
	if (aligned_new_start != aligned_old_start) { 
		if (aligned_new_start < aligned_old_start) { 
			if (!VirtualAlloc((void*)aligned_new_start, aligned_old_start - aligned_new_start, MEM_COMMIT, PAGE_READWRITE)) 
				return NULL; 
		} 
		else { 
			if (!VirtualFree((void*)aligned_old_start, aligned_new_start - aligned_old_start, MEM_DECOMMIT)) 
				return NULL; 
		} 
	} 
#else 
	if (stack->start < new_start) { 
		aligned_new_start = (sljit_uw)new_start & ~sljit_page_align; 
		aligned_old_start = ((sljit_uw)stack->start) & ~sljit_page_align; 
		/* If madvise is available, we release the unnecessary space. */ 
#if defined(MADV_DONTNEED) 
		if (aligned_new_start > aligned_old_start) 
			madvise((void*)aligned_old_start, aligned_new_start - aligned_old_start, MADV_DONTNEED); 
#elif defined(POSIX_MADV_DONTNEED) 
		if (aligned_new_start > aligned_old_start) 
			posix_madvise((void*)aligned_old_start, aligned_new_start - aligned_old_start, POSIX_MADV_DONTNEED); 
#endif 
	} 
#endif 
	stack->start = new_start; 
	return new_start; 
} 
 
#endif /* SLJIT_UTIL_STACK */ 
 
#endif