zend_shared_alloc.h

/*
   +----------------------------------------------------------------------+
   | Zend OPcache                                                         |
   +----------------------------------------------------------------------+
   | Copyright (c) 1998-2015 The PHP Group                                |
   +----------------------------------------------------------------------+
   | This source file is subject to version 3.01 of the PHP license,      |
   | that is bundled with this package in the file LICENSE, and is        |
   | available through the world-wide-web at the following url:           |
   | http://www.php.net/license/3_01.txt                                  |
   | If you did not receive a copy of the PHP license and are unable to   |
   | obtain it through the world-wide-web, please send a note to          |
   | license@php.net so we can mail you a copy immediately.               |
   +----------------------------------------------------------------------+
   | Authors: Andi Gutmans <andi@zend.com>                                |
   |          Zeev Suraski <zeev@zend.com>                                |
   |          Stanislav Malyshev <stas@zend.com>                          |
   |          Dmitry Stogov <dmitry@zend.com>                             |
   +----------------------------------------------------------------------+
*/

#ifndef ZEND_SHARED_ALLOC_H
#define ZEND_SHARED_ALLOC_H

#include "zend.h"
#include "ZendAccelerator.h"

#if defined(__APPLE__) && defined(__MACH__) /* darwin */
# ifdef HAVE_SHM_MMAP_POSIX
#  define USE_SHM_OPEN  1
# endif
# ifdef HAVE_SHM_MMAP_ANON
#  define USE_MMAP      1
# endif
#elif defined(__linux__) || defined(_AIX)
# ifdef HAVE_SHM_IPC
#  define USE_SHM       1
# endif
# ifdef HAVE_SHM_MMAP_ANON
#  define USE_MMAP      1
# endif
#elif defined(__sparc) || defined(__sun)
# ifdef HAVE_SHM_MMAP_POSIX
#  define USE_SHM_OPEN  1
# endif
# ifdef HAVE_SHM_IPC
#  define USE_SHM       1
# endif
# if defined(__i386)
#  ifdef HAVE_SHM_MMAP_ANON
#   define USE_MMAP     1
#  endif
# endif
#else
# ifdef HAVE_SHM_MMAP_POSIX
#  define USE_SHM_OPEN  1
# endif
# ifdef HAVE_SHM_MMAP_ANON
#  define USE_MMAP      1
# endif
# ifdef HAVE_SHM_IPC
#  define USE_SHM       1
# endif
#endif

#define ALLOC_FAILURE           0
#define ALLOC_SUCCESS           1
#define FAILED_REATTACHED       2
#define SUCCESSFULLY_REATTACHED 4
#define ALLOC_FAIL_MAPPING      8

typedef struct _zend_shared_segment {
    size_t  size;
    size_t  pos;  /* position for simple stack allocator */
    void   *p;
} zend_shared_segment;

typedef int (*create_segments_t)(size_t requested_size, zend_shared_segment ***shared_segments, int *shared_segment_count, char **error_in);
typedef int (*detach_segment_t)(zend_shared_segment *shared_segment);

typedef struct {
	create_segments_t create_segments;
	detach_segment_t detach_segment;
	size_t (*segment_type_size)(void);
} zend_shared_memory_handlers;

typedef struct _handler_entry {
	const char                  *name;
	zend_shared_memory_handlers *handler;
} zend_shared_memory_handler_entry;

typedef struct _zend_shared_memory_state {
	int *positions;   /* current positions for each segment */
	size_t shared_free; /* amount of free shared memory */
} zend_shared_memory_state;

typedef struct _zend_smm_shared_globals {
    /* Shared Memory Manager */
    zend_shared_segment      **shared_segments;
    /* Number of allocated shared segments */
    int                        shared_segments_count;
    /* Amount of free shared memory */
    size_t                     shared_free;
    /* Amount of shared memory allocated by garbage */
    int                        wasted_shared_memory;
    /* No more shared memory flag */
    zend_bool                  memory_exhausted;
    /* Saved Shared Allocator State */
    zend_shared_memory_state   shared_memory_state;
	/* Pointer to the application's shared data structures */
	void                      *app_shared_globals;
} zend_smm_shared_globals;

extern zend_smm_shared_globals *smm_shared_globals;

#define ZSMMG(element)		(smm_shared_globals->element)

#define SHARED_ALLOC_REATTACHED		(SUCCESS+1)

int zend_shared_alloc_startup(size_t requested_size);
void zend_shared_alloc_shutdown(void);

/* allocate shared memory block */
void *zend_shared_alloc(size_t size);

/* copy into shared memory */
void *_zend_shared_memdup(void *p, size_t size, zend_bool free_source TSRMLS_DC);
int  zend_shared_memdup_size(void *p, size_t size);

typedef union _align_test {
	void   *ptr;
	double  dbl;
	long    lng;
} align_test;

#if ZEND_GCC_VERSION >= 2000
# define PLATFORM_ALIGNMENT (__alignof__ (align_test))
#else
# define PLATFORM_ALIGNMENT (sizeof(align_test))
#endif

#define ZEND_ALIGNED_SIZE(size) \
	((size + PLATFORM_ALIGNMENT - 1) & ~(PLATFORM_ALIGNMENT - 1))

/* exclusive locking */
void zend_shared_alloc_lock(TSRMLS_D);
void zend_shared_alloc_unlock(TSRMLS_D); /* returns the allocated size during lock..unlock */
void zend_shared_alloc_safe_unlock(TSRMLS_D);

/* old/new mapping functions */
void zend_shared_alloc_clear_xlat_table(void);
void zend_shared_alloc_register_xlat_entry(const void *old, const void *new);
void *zend_shared_alloc_get_xlat_entry(const void *old);

size_t zend_shared_alloc_get_free_memory(void);
void zend_shared_alloc_save_state(void);
void zend_shared_alloc_restore_state(void);
const char *zend_accel_get_shared_model(void);

/* memory write protection */
void zend_accel_shared_protect(int mode TSRMLS_DC);

#ifdef USE_MMAP
extern zend_shared_memory_handlers zend_alloc_mmap_handlers;
#endif

#ifdef USE_SHM
extern zend_shared_memory_handlers zend_alloc_shm_handlers;
#endif

#ifdef USE_SHM_OPEN
extern zend_shared_memory_handlers zend_alloc_posix_handlers;
#endif

#ifdef ZEND_WIN32
extern zend_shared_memory_handlers zend_alloc_win32_handlers;
void zend_shared_alloc_create_lock(void);
void zend_shared_alloc_lock_win32(void);
void zend_shared_alloc_unlock_win32(void);
#endif

#endif /* ZEND_SHARED_ALLOC_H */