[ba776282] | 1 | /** |
---|
| 2 | * @file |
---|
| 3 | * |
---|
| 4 | * @brief Internal Support for POSIX Shared Memory |
---|
| 5 | */ |
---|
| 6 | |
---|
| 7 | /* |
---|
| 8 | * Copyright (c) 2016 Gedare Bloom. |
---|
| 9 | * |
---|
| 10 | * The license and distribution terms for this file may be |
---|
| 11 | * found in the file LICENSE in this distribution or at |
---|
| 12 | * http://www.rtems.org/license/LICENSE. |
---|
| 13 | */ |
---|
| 14 | |
---|
| 15 | #ifndef _RTEMS_POSIX_SHM_H |
---|
| 16 | #define _RTEMS_POSIX_SHM_H |
---|
| 17 | |
---|
| 18 | #include <rtems/score/object.h> |
---|
| 19 | #include <rtems/score/threadq.h> |
---|
| 20 | |
---|
[e97806a] | 21 | #include <sys/types.h> |
---|
| 22 | |
---|
[ba776282] | 23 | #ifdef __cplusplus |
---|
| 24 | extern "C" { |
---|
| 25 | #endif |
---|
| 26 | |
---|
| 27 | /** |
---|
| 28 | * @defgroup POSIXShmPrivate POSIX Shared Memory Private Support |
---|
| 29 | * |
---|
| 30 | * @ingroup POSIXAPI |
---|
| 31 | * |
---|
| 32 | * Internal implementation support for POSIX shared memory. |
---|
| 33 | * @{ |
---|
| 34 | */ |
---|
| 35 | typedef struct POSIX_Shm_Object_operations POSIX_Shm_Object_operations; |
---|
| 36 | extern const POSIX_Shm_Object_operations _POSIX_Shm_Object_operations; |
---|
| 37 | |
---|
| 38 | /** |
---|
| 39 | * @brief Encapsulation for the storage and manipulation of shm objects. |
---|
| 40 | */ |
---|
| 41 | typedef struct { |
---|
| 42 | /** |
---|
| 43 | * @brief The handle is private for finding object storage. |
---|
| 44 | */ |
---|
| 45 | void *handle; |
---|
| 46 | |
---|
| 47 | /** |
---|
| 48 | * @brief The number of bytes allocated to the object. A size of 0 with |
---|
| 49 | * a handle of NULL means no object is allocated. |
---|
| 50 | */ |
---|
| 51 | size_t size; |
---|
| 52 | |
---|
| 53 | /** |
---|
| 54 | * @brief Implementation-specific operations on shm objects. |
---|
| 55 | */ |
---|
| 56 | const POSIX_Shm_Object_operations *ops; |
---|
| 57 | } POSIX_Shm_Object; |
---|
| 58 | |
---|
| 59 | /** |
---|
| 60 | * @brief Operations on POSIX Shared Memory Objects. |
---|
| 61 | */ |
---|
| 62 | struct POSIX_Shm_Object_operations { |
---|
| 63 | /** |
---|
| 64 | * @brief Allocates a new @a shm_obj with initial @a size. |
---|
| 65 | * |
---|
| 66 | * New shared memory is initialized to zeroes. |
---|
| 67 | * |
---|
| 68 | * Returns 0 for success. |
---|
| 69 | */ |
---|
| 70 | int ( *object_create ) ( POSIX_Shm_Object *shm_obj, size_t size ); |
---|
| 71 | |
---|
| 72 | /** |
---|
| 73 | * @brief Changes the @a shm_obj size to @a size. |
---|
| 74 | * |
---|
| 75 | * Zeroes out the portion of the shared memory object that shrinks or grows. |
---|
| 76 | * |
---|
| 77 | * Returns 0 for success. |
---|
| 78 | */ |
---|
| 79 | int ( *object_resize ) ( POSIX_Shm_Object *shm_obj, size_t size ); |
---|
| 80 | |
---|
| 81 | /** |
---|
| 82 | * @brief Deletes the @a shm_obj. |
---|
| 83 | * |
---|
| 84 | * Zeroes out the memory. |
---|
| 85 | * |
---|
| 86 | * Returns 0 for success. |
---|
| 87 | */ |
---|
| 88 | int ( *object_delete ) ( POSIX_Shm_Object *shm_obj ); |
---|
| 89 | |
---|
| 90 | /** |
---|
| 91 | * @brief Copies up to @count bytes of the @a shm_obj data into @a buf. |
---|
| 92 | * |
---|
| 93 | * Returns the number of bytes read (copied) into @a buf. |
---|
| 94 | */ |
---|
| 95 | int ( *object_read ) ( POSIX_Shm_Object *shm_obj, void *buf, size_t count ); |
---|
[87de70a2] | 96 | |
---|
| 97 | /** |
---|
| 98 | * @brief Maps a shared memory object. |
---|
| 99 | * |
---|
| 100 | * Establishes a memory mapping between the shared memory object and the |
---|
| 101 | * caller. |
---|
| 102 | * |
---|
| 103 | * Returns the mapped address of the object. |
---|
| 104 | */ |
---|
| 105 | void * ( *object_mmap ) ( POSIX_Shm_Object *shm_obj, size_t len, int prot, off_t off); |
---|
[ba776282] | 106 | }; |
---|
| 107 | |
---|
| 108 | /** |
---|
| 109 | * @brief Control for a POSIX Shared Memory Object |
---|
| 110 | */ |
---|
| 111 | typedef struct { |
---|
| 112 | Objects_Control Object; |
---|
| 113 | Thread_queue_Control Wait_queue; |
---|
| 114 | |
---|
| 115 | int reference_count; |
---|
| 116 | |
---|
| 117 | POSIX_Shm_Object shm_object; |
---|
| 118 | |
---|
| 119 | uid_t uid; |
---|
| 120 | gid_t gid; |
---|
| 121 | mode_t mode; |
---|
[ea4488ae] | 122 | int oflag; |
---|
[ba776282] | 123 | |
---|
| 124 | time_t atime; |
---|
| 125 | time_t mtime; |
---|
| 126 | time_t ctime; |
---|
| 127 | } POSIX_Shm_Control; |
---|
| 128 | |
---|
[e97806a] | 129 | extern const uint32_t _Configuration_POSIX_Maximum_shms; |
---|
| 130 | |
---|
[ba776282] | 131 | /** |
---|
| 132 | * @brief object_create operation for shm objects stored in RTEMS Workspace. |
---|
| 133 | */ |
---|
| 134 | extern int _POSIX_Shm_Object_create_from_workspace( |
---|
| 135 | POSIX_Shm_Object *shm_obj, |
---|
| 136 | size_t size |
---|
| 137 | ); |
---|
| 138 | |
---|
| 139 | /** |
---|
| 140 | * @brief object_delete operation for shm objects stored in RTEMS Workspace. |
---|
| 141 | */ |
---|
| 142 | extern int _POSIX_Shm_Object_delete_from_workspace( POSIX_Shm_Object *shm_obj ); |
---|
| 143 | |
---|
| 144 | /** |
---|
| 145 | * @brief object_resize operation for shm objects stored in RTEMS Workspace. |
---|
| 146 | */ |
---|
| 147 | extern int _POSIX_Shm_Object_resize_from_workspace( |
---|
| 148 | POSIX_Shm_Object *shm_obj, |
---|
| 149 | size_t size |
---|
| 150 | ); |
---|
| 151 | |
---|
| 152 | /** |
---|
| 153 | * @brief object_read operation for shm objects stored in RTEMS Workspace. |
---|
| 154 | */ |
---|
| 155 | extern int _POSIX_Shm_Object_read_from_workspace( |
---|
| 156 | POSIX_Shm_Object *shm_obj, |
---|
| 157 | void *buf, |
---|
| 158 | size_t count |
---|
| 159 | ); |
---|
| 160 | |
---|
[87de70a2] | 161 | /** |
---|
| 162 | * @brief object_mmap operation for shm objects stored in RTEMS Workspace. |
---|
| 163 | */ |
---|
| 164 | extern void * _POSIX_Shm_Object_mmap_from_workspace( |
---|
| 165 | POSIX_Shm_Object *shm_obj, |
---|
| 166 | size_t len, |
---|
| 167 | int prot, |
---|
| 168 | off_t off |
---|
| 169 | ); |
---|
| 170 | |
---|
[ba776282] | 171 | /** |
---|
| 172 | * @brief object_create operation for shm objects stored in C program heap. |
---|
| 173 | */ |
---|
| 174 | extern int _POSIX_Shm_Object_create_from_heap( |
---|
| 175 | POSIX_Shm_Object *shm_obj, |
---|
| 176 | size_t size |
---|
| 177 | ); |
---|
| 178 | |
---|
| 179 | /** |
---|
| 180 | * @brief object_delete operation for shm objects stored in C program heap. |
---|
| 181 | */ |
---|
| 182 | extern int _POSIX_Shm_Object_delete_from_heap( POSIX_Shm_Object *shm_obj ); |
---|
| 183 | |
---|
| 184 | /** |
---|
| 185 | * @brief object_resize operation for shm objects stored in C program heap. |
---|
| 186 | */ |
---|
| 187 | extern int _POSIX_Shm_Object_resize_from_heap( |
---|
| 188 | POSIX_Shm_Object *shm_obj, |
---|
| 189 | size_t size |
---|
| 190 | ); |
---|
| 191 | |
---|
| 192 | /** |
---|
| 193 | * @brief object_read operation for shm objects stored in C program heap. |
---|
| 194 | */ |
---|
| 195 | extern int _POSIX_Shm_Object_read_from_heap( |
---|
| 196 | POSIX_Shm_Object *shm_obj, |
---|
| 197 | void *buf, |
---|
| 198 | size_t count |
---|
| 199 | ); |
---|
| 200 | |
---|
[87de70a2] | 201 | /** |
---|
| 202 | * @brief object_mmap operation for shm objects stored in C program heap. |
---|
| 203 | */ |
---|
| 204 | extern void * _POSIX_Shm_Object_mmap_from_heap( |
---|
| 205 | POSIX_Shm_Object *shm_obj, |
---|
| 206 | size_t len, |
---|
| 207 | int prot, |
---|
| 208 | off_t off |
---|
| 209 | ); |
---|
| 210 | |
---|
[ba776282] | 211 | /** @} */ |
---|
| 212 | |
---|
| 213 | #ifdef __cplusplus |
---|
| 214 | } |
---|
| 215 | #endif |
---|
| 216 | |
---|
| 217 | #endif |
---|