diff options
Diffstat (limited to 'common/shm.h')
| -rw-r--r-- | common/shm.h | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/common/shm.h b/common/shm.h new file mode 100644 index 00000000..2ef29fc4 --- /dev/null +++ b/common/shm.h @@ -0,0 +1,156 @@ +#ifndef __jack_shm_h__ +#define __jack_shm_h__ + +#include <limits.h> +#include <sys/types.h> +#include "types.h" +#include "JackExports.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_SERVER_NAME_SIZE 256 /* maximum length of server name */ +#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 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 // steph TO CHECK +#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; + +#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 */ + } jack_shmtype_t; + + typedef int16_t jack_shm_registry_index_t; + + /** + * 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]; + } + 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 */ + } + 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. + */ + typedef struct _jack_shm_info { + jack_shm_registry_index_t index; /* offset into the registry */ + void *attached_at; /* address where attached */ + } + jack_shm_info_t; + + /* utility functions used only within JACK */ + + extern void jack_shm_copy_from_registry (jack_shm_info_t*, + jack_shm_registry_index_t); + extern void jack_shm_copy_to_registry (jack_shm_info_t*, + jack_shm_registry_index_t*); + extern void jack_release_shm_info (jack_shm_registry_index_t); + + extern char* jack_shm_addr (jack_shm_info_t* si); // steph + + /* here beginneth the API */ + + EXPORT extern int jack_register_server (const char *server_name); + EXPORT extern void jack_unregister_server (const char *server_name); + + extern int jack_initialize_shm (const char *server_name); + extern int jack_initialize_shm_server (void); // steph + extern int jack_initialize_shm_client (void); // steph + EXPORT extern int jack_cleanup_shm (void); + + extern int jack_shmalloc (const char *shm_name, jack_shmsize_t size, + jack_shm_info_t* result); + extern void jack_release_shm (jack_shm_info_t*); + extern void jack_destroy_shm (jack_shm_info_t*); + extern int jack_attach_shm (jack_shm_info_t*); + extern int jack_attach_shm_read (jack_shm_info_t*); // steph + extern int jack_resize_shm (jack_shm_info_t*, jack_shmsize_t size); + +#ifdef __cplusplus +} +#endif + +#endif /* __jack_shm_h__ */ |