-
Notifications
You must be signed in to change notification settings - Fork 1
/
drvrsmem.h
179 lines (132 loc) · 6.38 KB
/
drvrsmem.h
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
/* S H A R E D M E M O R Y D R I V E R
=======================================
by Jerzy.Borkowski@obs.unige.ch
09-Mar-98 : initial version 1.0 released
23-Mar-98 : shared_malloc now accepts new handle as an argument
*/
#include <sys/ipc.h> /* this is necessary for Solaris/Linux */
#include <sys/shm.h>
#include <sys/sem.h>
#ifdef _AIX
#include <fcntl.h>
#else
#include <sys/fcntl.h>
#endif
/* configuration parameters */
#define SHARED_MAXSEG (16) /* maximum number of shared memory blocks */
#define SHARED_KEYBASE (14011963) /* base for shared memory keys, may be overriden by getenv */
#define SHARED_FDNAME ("/tmp/.shmem-lockfile") /* template for lock file name */
#define SHARED_ENV_KEYBASE ("SHMEM_LIB_KEYBASE") /* name of environment variable */
#define SHARED_ENV_MAXSEG ("SHMEM_LIB_MAXSEG") /* name of environment variable */
/* useful constants */
#define SHARED_RDONLY (0) /* flag for shared_(un)lock, lock for read */
#define SHARED_RDWRITE (1) /* flag for shared_(un)lock, lock for write */
#define SHARED_WAIT (0) /* flag for shared_lock, block if cannot lock immediate */
#define SHARED_NOWAIT (2) /* flag for shared_lock, fail if cannot lock immediate */
#define SHARED_NOLOCK (0x100) /* flag for shared_validate function */
#define SHARED_RESIZE (4) /* flag for shared_malloc, object is resizeable */
#define SHARED_PERSIST (8) /* flag for shared_malloc, object is not deleted after last proc detaches */
#define SHARED_INVALID (-1) /* invalid handle for semaphore/shared memory */
#define SHARED_EMPTY (0) /* entries for shared_used table */
#define SHARED_USED (1)
#define SHARED_GRANUL (16384) /* granularity of shared_malloc allocation = phys page size, system dependent */
/* checkpoints in shared memory segments - might be omitted */
#define SHARED_ID_0 ('J') /* first byte of identifier in BLKHEAD */
#define SHARED_ID_1 ('B') /* second byte of identifier in BLKHEAD */
#define BLOCK_REG (0) /* value for tflag member of BLKHEAD */
#define BLOCK_SHARED (1) /* value for tflag member of BLKHEAD */
/* generic error codes */
#define SHARED_OK (0)
#define SHARED_ERR_MIN_IDX SHARED_BADARG
#define SHARED_ERR_MAX_IDX SHARED_NORESIZE
#define DAL_SHM_FREE (0)
#define DAL_SHM_USED (1)
#define DAL_SHM_ID0 ('D')
#define DAL_SHM_ID1 ('S')
#define DAL_SHM_ID2 ('M')
#define DAL_SHM_SEGHEAD_ID (0x19630114)
/* data types */
/* BLKHEAD object is placed at the beginning of every memory segment (both
shared and regular) to allow automatic recognition of segments type */
typedef union
{ struct BLKHEADstruct
{ char ID[2]; /* ID = 'JB', just as a checkpoint */
char tflag; /* is it shared memory or regular one ? */
int handle; /* this is not necessary, used only for non-resizeable objects via ptr */
} s;
double d; /* for proper alignment on every machine */
} BLKHEAD;
typedef void *SHARED_P; /* generic type of shared memory pointer */
typedef struct SHARED_GTABstruct /* data type used in global table */
{ int sem; /* access semaphore (1 field): process count */
int semkey; /* key value used to generate semaphore handle */
int key; /* key value used to generate shared memory handle (realloc changes it) */
int handle; /* handle of shared memory segment */
int size; /* size of shared memory segment */
int nprocdebug; /* attached proc counter, helps remove zombie segments */
char attr; /* attributes of shared memory object */
} SHARED_GTAB;
typedef struct SHARED_LTABstruct /* data type used in local table */
{ BLKHEAD *p; /* pointer to segment (may be null) */
int tcnt; /* number of threads in this process attached to segment */
int lkcnt; /* >=0 <- number of read locks, -1 - write lock */
long seekpos; /* current pointer position, read/write/seek operations change it */
} SHARED_LTAB;
/* system dependent definitions */
#ifndef HAVE_FLOCK_T
typedef struct flock flock_t;
#define HAVE_FLOCK_T
#endif
#ifndef HAVE_UNION_SEMUN
union semun
{ int val;
struct semid_ds *buf;
unsigned short *array;
};
#define HAVE_UNION_SEMUN
#endif
typedef struct DAL_SHM_SEGHEAD_STRUCT DAL_SHM_SEGHEAD;
struct DAL_SHM_SEGHEAD_STRUCT
{ int ID; /* ID for debugging */
int h; /* handle of sh. mem */
int size; /* size of data area */
int nodeidx; /* offset of root object (node struct typically) */
};
/* API routines */
#ifdef __cplusplus
extern "C" {
#endif
void shared_cleanup(void); /* must be called at exit/abort */
int shared_init(int debug_msgs); /* must be called before any other shared memory routine */
int shared_recover(int id); /* try to recover dormant segment(s) after applic crash */
int shared_malloc(long size, int mode, int newhandle); /* allocate n-bytes of shared memory */
int shared_attach(int idx); /* attach to segment given index to table */
int shared_free(int idx); /* release shared memory */
SHARED_P shared_lock(int idx, int mode); /* lock segment for reading */
SHARED_P shared_realloc(int idx, long newsize); /* reallocate n-bytes of shared memory (ON LOCKED SEGMENT ONLY) */
int shared_size(int idx); /* get size of attached shared memory segment (ON LOCKED SEGMENT ONLY) */
int shared_attr(int idx); /* get attributes of attached shared memory segment (ON LOCKED SEGMENT ONLY) */
int shared_set_attr(int idx, int newattr); /* set attributes of attached shared memory segment (ON LOCKED SEGMENT ONLY) */
int shared_unlock(int idx); /* unlock segment (ON LOCKED SEGMENT ONLY) */
int shared_set_debug(int debug_msgs); /* set/reset debug mode */
int shared_set_createmode(int mode); /* set/reset debug mode */
int shared_list(int id); /* list segment(s) */
int shared_uncond_delete(int id); /* uncondintionally delete (NOWAIT operation) segment(s) */
int shared_getaddr(int id, char **address); /* get starting address of FITS file in segment */
int smem_init(void);
int smem_shutdown(void);
int smem_setoptions(int options);
int smem_getoptions(int *options);
int smem_getversion(int *version);
int smem_open(char *filename, int rwmode, int *driverhandle);
int smem_create(char *filename, int *driverhandle);
int smem_close(int driverhandle);
int smem_remove(char *filename);
int smem_size(int driverhandle, LONGLONG *size);
int smem_flush(int driverhandle);
int smem_seek(int driverhandle, LONGLONG offset);
int smem_read(int driverhandle, void *buffer, long nbytes);
int smem_write(int driverhandle, void *buffer, long nbytes);
#ifdef __cplusplus
}
#endif