1 | /** |
---|
2 | * @file |
---|
3 | */ |
---|
4 | |
---|
5 | /* |
---|
6 | * Copyright (c) 2016 Gedare Bloom. |
---|
7 | * |
---|
8 | * The license and distribution terms for this file may be |
---|
9 | * found in the file LICENSE in this distribution or at |
---|
10 | * http://www.rtems.org/license/LICENSE. |
---|
11 | */ |
---|
12 | |
---|
13 | #if HAVE_CONFIG_H |
---|
14 | #include "config.h" |
---|
15 | #endif |
---|
16 | |
---|
17 | #include <errno.h> |
---|
18 | #include <stdlib.h> |
---|
19 | #include <string.h> |
---|
20 | #include <rtems/posix/shmimpl.h> |
---|
21 | |
---|
22 | int _POSIX_Shm_Object_create_from_heap( |
---|
23 | POSIX_Shm_Object *shm_obj, |
---|
24 | size_t size |
---|
25 | ) |
---|
26 | { |
---|
27 | void *p = calloc( 1, size ); /* get zero'd memory */ |
---|
28 | if ( p != NULL ) { |
---|
29 | shm_obj->handle = p; |
---|
30 | shm_obj->size = size; |
---|
31 | } else { |
---|
32 | errno = EIO; |
---|
33 | } |
---|
34 | return 0; |
---|
35 | } |
---|
36 | |
---|
37 | int _POSIX_Shm_Object_delete_from_heap( POSIX_Shm_Object *shm_obj ) |
---|
38 | { |
---|
39 | /* zero out memory before releasing it. */ |
---|
40 | memset( shm_obj->handle, 0, shm_obj->size ); |
---|
41 | free( shm_obj->handle ); |
---|
42 | shm_obj->handle = NULL; |
---|
43 | shm_obj->size = 0; |
---|
44 | return 0; |
---|
45 | } |
---|
46 | |
---|
47 | int _POSIX_Shm_Object_resize_from_heap( |
---|
48 | POSIX_Shm_Object *shm_obj, |
---|
49 | size_t size |
---|
50 | ) |
---|
51 | { |
---|
52 | void *p; |
---|
53 | int err = 0; |
---|
54 | |
---|
55 | if ( size < shm_obj->size ) { |
---|
56 | /* zero out if shrinking */ |
---|
57 | p = (void*)((uintptr_t)shm_obj->handle + (uintptr_t)size); |
---|
58 | memset( p, 0, shm_obj->size - size ); |
---|
59 | } |
---|
60 | p = realloc( shm_obj->handle, size ); |
---|
61 | if ( p != NULL ) { |
---|
62 | shm_obj->handle = p; |
---|
63 | if ( size > shm_obj->size ) { |
---|
64 | /* initialize added memory */ |
---|
65 | memset( p, 0, size - shm_obj->size ); |
---|
66 | } |
---|
67 | shm_obj->size = size; |
---|
68 | } else { |
---|
69 | err = EIO; |
---|
70 | } |
---|
71 | return err; |
---|
72 | } |
---|
73 | |
---|
74 | /* This is identical to _POSIX_Shm_Object_read_from_wkspace */ |
---|
75 | int _POSIX_Shm_Object_read_from_heap( |
---|
76 | POSIX_Shm_Object *shm_obj, |
---|
77 | void *buf, |
---|
78 | size_t count |
---|
79 | ) |
---|
80 | { |
---|
81 | if ( shm_obj == NULL || shm_obj->handle == NULL ) |
---|
82 | return 0; |
---|
83 | |
---|
84 | if ( shm_obj->size < count ) { |
---|
85 | count = shm_obj->size; |
---|
86 | } |
---|
87 | |
---|
88 | memcpy( buf, shm_obj->handle, count ); |
---|
89 | |
---|
90 | return count; |
---|
91 | } |
---|
92 | |
---|
93 | /* This is identical to _POSIX_Shm_Object_mmap_from_wkspace */ |
---|
94 | void * _POSIX_Shm_Object_mmap_from_heap( |
---|
95 | POSIX_Shm_Object *shm_obj, |
---|
96 | size_t len, |
---|
97 | int prot, |
---|
98 | off_t off |
---|
99 | ) |
---|
100 | { |
---|
101 | if ( shm_obj == NULL || shm_obj->handle == NULL ) |
---|
102 | return 0; |
---|
103 | |
---|
104 | /* This is already checked by mmap. Maybe make it a debug assert? */ |
---|
105 | if ( shm_obj->size < len + off ) { |
---|
106 | return NULL; |
---|
107 | } |
---|
108 | |
---|
109 | return (char*)shm_obj->handle + off; |
---|
110 | } |
---|
111 | |
---|