223 lines
6.7 KiB
C
223 lines
6.7 KiB
C
/* This module provides a set of abstract shared memory interfaces
|
|
* with support using both System V and POSIX shared memory
|
|
* implementations. The code is divided into three sections:
|
|
*
|
|
* - common (interface-independent) code
|
|
* - POSIX implementation
|
|
* - System V implementation
|
|
* - Windows implementation
|
|
*
|
|
* The implementation used is determined by whether USE_POSIX_SHM was
|
|
* set in the ./configure step.
|
|
*/
|
|
|
|
/*
|
|
Copyright (C) 2001-2003 Paul Davis
|
|
Copyright (C) 2005-2012 Grame
|
|
|
|
This program is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU Lesser General Public License as published by
|
|
the Free Software Foundation; either version 2.1 of the License, or
|
|
(at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public License
|
|
along with this program; if not, write to the Free Software
|
|
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
|
|
|
|
*/
|
|
|
|
#ifndef __jack_shm_h__
|
|
#define __jack_shm_h__
|
|
|
|
#include <limits.h>
|
|
#include <sys/types.h>
|
|
#include "types.h"
|
|
#include "JackCompilerDeps.h"
|
|
#include "JackConstants.h"
|
|
|
|
#define TRUE 1
|
|
#define FALSE 0
|
|
|
|
#ifdef __cplusplus
|
|
extern "C"
|
|
{
|
|
#endif
|
|
|
|
#define MAX_SERVERS 8 /* maximum concurrent servers */
|
|
#define MAX_SHM_ID 256 /* generally about 16 per server */
|
|
#define JACK_SHM_MAGIC 0x4a41434b /* shm magic number: "JACK" */
|
|
#define JACK_SHM_NULL_INDEX -1 /* NULL SHM index */
|
|
#define JACK_SHM_REGISTRY_INDEX -2 /* pseudo SHM index for registry */
|
|
|
|
|
|
/* On Mac OS X, SHM_NAME_MAX is the maximum length of a shared memory
|
|
* segment name (instead of NAME_MAX or PATH_MAX as defined by the
|
|
* standard).
|
|
*/
|
|
#ifdef USE_POSIX_SHM
|
|
|
|
#ifndef NAME_MAX
|
|
#define NAME_MAX 255
|
|
#endif
|
|
|
|
#ifndef SHM_NAME_MAX
|
|
#define SHM_NAME_MAX NAME_MAX
|
|
#endif
|
|
typedef char shm_name_t[SHM_NAME_MAX];
|
|
typedef shm_name_t jack_shm_id_t;
|
|
|
|
#elif WIN32
|
|
#define NAME_MAX 255
|
|
#ifndef SHM_NAME_MAX
|
|
#define SHM_NAME_MAX NAME_MAX
|
|
#endif
|
|
typedef char shm_name_t[SHM_NAME_MAX];
|
|
typedef shm_name_t jack_shm_id_t;
|
|
|
|
#elif __ANDROID__
|
|
|
|
#ifndef NAME_MAX
|
|
#define NAME_MAX 255
|
|
#endif
|
|
|
|
#ifndef SHM_NAME_MAX
|
|
#define SHM_NAME_MAX NAME_MAX
|
|
#endif
|
|
typedef char shm_name_t[SHM_NAME_MAX];
|
|
typedef shm_name_t jack_shm_id_t;
|
|
typedef int jack_shm_fd_t;
|
|
|
|
#else
|
|
/* System V SHM */
|
|
typedef int jack_shm_id_t;
|
|
#endif /* SHM type */
|
|
|
|
/* shared memory type */
|
|
typedef enum {
|
|
shm_POSIX = 1, /* POSIX shared memory */
|
|
shm_SYSV = 2, /* System V shared memory */
|
|
shm_WIN32 = 3, /* Windows 32 shared memory */
|
|
shm_ANDROID = 4 /* Android shared memory */
|
|
} jack_shmtype_t;
|
|
|
|
#ifdef __APPLE__
|
|
/* we need to align and pack data to 32bit so that x86_64 and arm64 work together */
|
|
typedef int32_t jack_shm_registry_index_t;
|
|
#else
|
|
typedef int16_t jack_shm_registry_index_t;
|
|
#endif
|
|
|
|
/**
|
|
* A structure holding information about shared memory allocated by
|
|
* JACK. this persists across invocations of JACK, and can be used by
|
|
* multiple JACK servers. It contains no pointers and is valid across
|
|
* address spaces.
|
|
*
|
|
* The registry consists of two parts: a header including an array of
|
|
* server names, followed by an array of segment registry entries.
|
|
*/
|
|
typedef struct _jack_shm_server {
|
|
#ifdef WIN32
|
|
int pid; /* process ID */
|
|
#else
|
|
pid_t pid; /* process ID */
|
|
#endif
|
|
|
|
char name[JACK_SERVER_NAME_SIZE+1];
|
|
}
|
|
jack_shm_server_t;
|
|
|
|
typedef struct _jack_shm_header {
|
|
uint32_t magic; /* magic number */
|
|
uint16_t protocol; /* JACK protocol version */
|
|
jack_shmtype_t type; /* shm type */
|
|
jack_shmsize_t size; /* total registry segment size */
|
|
jack_shmsize_t hdr_len; /* size of header */
|
|
jack_shmsize_t entry_len; /* size of registry entry */
|
|
jack_shm_server_t server[MAX_SERVERS]; /* current server array */
|
|
}
|
|
jack_shm_header_t;
|
|
|
|
typedef struct _jack_shm_registry {
|
|
jack_shm_registry_index_t index; /* offset into the registry */
|
|
|
|
#ifdef WIN32
|
|
int allocator; /* PID that created shm segment */
|
|
#else
|
|
pid_t allocator; /* PID that created shm segment */
|
|
#endif
|
|
|
|
jack_shmsize_t size; /* for POSIX unattach */
|
|
jack_shm_id_t id; /* API specific, see above */
|
|
#ifdef __ANDROID__
|
|
jack_shm_fd_t fd;
|
|
#endif
|
|
}
|
|
jack_shm_registry_t;
|
|
|
|
#define JACK_SHM_REGISTRY_SIZE (sizeof (jack_shm_header_t) \
|
|
+ sizeof (jack_shm_registry_t) * MAX_SHM_ID)
|
|
|
|
/**
|
|
* a structure holding information about shared memory
|
|
* allocated by JACK. this version is valid only
|
|
* for a given address space. It contains a pointer
|
|
* indicating where the shared memory has been
|
|
* attached to the address space.
|
|
*/
|
|
|
|
PRE_PACKED_STRUCTURE
|
|
struct _jack_shm_info {
|
|
jack_shm_registry_index_t index; /* offset into the registry */
|
|
uint32_t size;
|
|
#ifdef __ANDROID__
|
|
jack_shm_fd_t fd;
|
|
#endif
|
|
union {
|
|
void *attached_at; /* address where attached */
|
|
char ptr_size[8];
|
|
} ptr; /* a "pointer" that has the same 8 bytes size when compiling in 32 or 64 bits */
|
|
} POST_PACKED_STRUCTURE;
|
|
|
|
typedef struct _jack_shm_info jack_shm_info_t;
|
|
|
|
/* utility functions used only within JACK */
|
|
|
|
void jack_shm_copy_from_registry (jack_shm_info_t*,
|
|
jack_shm_registry_index_t);
|
|
void jack_shm_copy_to_registry (jack_shm_info_t*,
|
|
jack_shm_registry_index_t*);
|
|
int jack_release_shm_info (jack_shm_registry_index_t);
|
|
char* jack_shm_addr (jack_shm_info_t* si);
|
|
|
|
/* here begin the API */
|
|
int jack_register_server (const char *server_name, int new_registry);
|
|
int jack_unregister_server (const char *server_name);
|
|
|
|
int jack_initialize_shm (const char *server_name);
|
|
int jack_initialize_shm_server (void);
|
|
int jack_initialize_shm_client (void);
|
|
int jack_cleanup_shm (void);
|
|
|
|
int jack_shmalloc (const char *shm_name, jack_shmsize_t size,
|
|
jack_shm_info_t* result);
|
|
void jack_release_shm (jack_shm_info_t*);
|
|
void jack_release_lib_shm (jack_shm_info_t*);
|
|
void jack_destroy_shm (jack_shm_info_t*);
|
|
int jack_attach_shm (jack_shm_info_t*);
|
|
int jack_attach_lib_shm (jack_shm_info_t*);
|
|
int jack_attach_shm_read (jack_shm_info_t*);
|
|
int jack_attach_lib_shm_read (jack_shm_info_t*);
|
|
int jack_resize_shm (jack_shm_info_t*, jack_shmsize_t size);
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
|
|
#endif /* __jack_shm_h__ */
|