rf-web/vendor/bundle/gems/ffi-1.11.1/ext/ffi_c/ClosurePool.c

284 lines
7.0 KiB
C
Raw Normal View History

2019-10-21 08:18:17 +00:00
/*
* Copyright (c) 2009, 2010 Wayne Meissner
* Copyright (c) 2008-2013, Ruby FFI project contributors
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
* * Neither the name of the Ruby FFI project nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 <COPYRIGHT HOLDER> 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.
*/
#ifndef _MSC_VER
#include <sys/param.h>
#endif
#include <sys/types.h>
#if defined(__CYGWIN__) || !defined(_WIN32)
# include <sys/mman.h>
#endif
#include <stdio.h>
#ifndef _MSC_VER
# include <stdint.h>
# include <stdbool.h>
#else
# include "win32/stdbool.h"
# include "win32/stdint.h"
#endif
#if defined(__CYGWIN__) || !defined(_WIN32)
# include <unistd.h>
#else
# include <winsock2.h>
# define _WINSOCKAPI_
# include <windows.h>
#endif
#include <errno.h>
#include <ruby.h>
#if defined(_MSC_VER) && !defined(INT8_MIN)
# include "win32/stdint.h"
#endif
#include <ffi.h>
#include "rbffi.h"
#include "compat.h"
#include "Function.h"
#include "Types.h"
#include "Type.h"
#include "LastError.h"
#include "Call.h"
#include "ClosurePool.h"
#ifndef roundup
# define roundup(x, y) ((((x)+((y)-1))/(y))*(y))
#endif
#ifdef _WIN32
typedef char* caddr_t;
#endif
typedef struct Memory {
void* code;
void* data;
struct Memory* next;
} Memory;
struct ClosurePool_ {
void* ctx;
int closureSize;
bool (*prep)(void* ctx, void *code, Closure* closure, char* errbuf, size_t errbufsize);
struct Memory* blocks; /* Keeps track of all the allocated memory for this pool */
Closure* list;
long refcnt;
};
static long pageSize;
static void* allocatePage(void);
static bool freePage(void *);
static bool protectPage(void *);
ClosurePool*
rbffi_ClosurePool_New(int closureSize,
bool (*prep)(void* ctx, void *code, Closure* closure, char* errbuf, size_t errbufsize),
void* ctx)
{
ClosurePool* pool;
pool = xcalloc(1, sizeof(*pool));
pool->closureSize = closureSize;
pool->ctx = ctx;
pool->prep = prep;
pool->refcnt = 1;
return pool;
}
void
cleanup_closure_pool(ClosurePool* pool)
{
Memory* memory;
for (memory = pool->blocks; memory != NULL; ) {
Memory* next = memory->next;
freePage(memory->code);
free(memory->data);
free(memory);
memory = next;
}
xfree(pool);
}
void
rbffi_ClosurePool_Free(ClosurePool* pool)
{
if (pool != NULL) {
long refcnt = --(pool->refcnt);
if (refcnt == 0) {
cleanup_closure_pool(pool);
}
}
}
Closure*
rbffi_Closure_Alloc(ClosurePool* pool)
{
Closure *list = NULL;
Memory* block = NULL;
caddr_t code = NULL;
char errmsg[256];
int nclosures;
long trampolineSize;
int i;
if (pool->list != NULL) {
Closure* closure = pool->list;
pool->list = pool->list->next;
pool->refcnt++;
return closure;
}
trampolineSize = roundup(pool->closureSize, 8);
nclosures = (int) (pageSize / trampolineSize);
block = calloc(1, sizeof(*block));
list = calloc(nclosures, sizeof(*list));
code = allocatePage();
if (block == NULL || list == NULL || code == NULL) {
snprintf(errmsg, sizeof(errmsg), "failed to allocate a page. errno=%d (%s)", errno, strerror(errno));
goto error;
}
for (i = 0; i < nclosures; ++i) {
Closure* closure = &list[i];
closure->next = &list[i + 1];
closure->pool = pool;
closure->code = (code + (i * trampolineSize));
if (!(*pool->prep)(pool->ctx, closure->code, closure, errmsg, sizeof(errmsg))) {
goto error;
}
}
if (!protectPage(code)) {
goto error;
}
/* Track the allocated page + Closure memory area */
block->data = list;
block->code = code;
block->next = pool->blocks;
pool->blocks = block;
/* Thread the new block onto the free list, apart from the first one. */
list[nclosures - 1].next = pool->list;
pool->list = list->next;
pool->refcnt++;
/* Use the first one as the new handle */
return list;
error:
free(block);
free(list);
if (code != NULL) {
freePage(code);
}
rb_raise(rb_eRuntimeError, "%s", errmsg);
return NULL;
}
void
rbffi_Closure_Free(Closure* closure)
{
if (closure != NULL) {
ClosurePool* pool = closure->pool;
long refcnt;
/* Just push it on the front of the free list */
closure->next = pool->list;
pool->list = closure;
refcnt = --(pool->refcnt);
if (refcnt == 0) {
cleanup_closure_pool(pool);
}
}
}
void*
rbffi_Closure_CodeAddress(Closure* handle)
{
return handle->code;
}
static long
getPageSize()
{
#if !defined(__CYGWIN__) && (defined(_WIN32) || defined(__WIN32__))
SYSTEM_INFO si;
GetSystemInfo(&si);
return si.dwPageSize;
#else
return sysconf(_SC_PAGESIZE);
#endif
}
static void*
allocatePage(void)
{
#if !defined(__CYGWIN__) && (defined(_WIN32) || defined(__WIN32__))
return VirtualAlloc(NULL, pageSize, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);
#else
caddr_t page = mmap(NULL, pageSize, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0);
return (page != (caddr_t) -1) ? page : NULL;
#endif
}
static bool
freePage(void *addr)
{
#if !defined(__CYGWIN__) && (defined(_WIN32) || defined(__WIN32__))
return VirtualFree(addr, 0, MEM_RELEASE);
#else
return munmap(addr, pageSize) == 0;
#endif
}
static bool
protectPage(void* page)
{
#if !defined(__CYGWIN__) && (defined(_WIN32) || defined(__WIN32__))
DWORD oldProtect;
return VirtualProtect(page, pageSize, PAGE_EXECUTE_READ, &oldProtect);
#else
return mprotect(page, pageSize, PROT_READ | PROT_EXEC) == 0;
#endif
}
void
rbffi_ClosurePool_Init(VALUE module)
{
pageSize = getPageSize();
}