1 /****************************************************************************
2 **
3 ** Copyright (C) 2015 Intel Corporation
4 **
5 ** Permission is hereby granted, free of charge, to any person obtaining a copy
6 ** of this software and associated documentation files (the "Software"), to deal
7 ** in the Software without restriction, including without limitation the rights
8 ** to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
9 ** copies of the Software, and to permit persons to whom the Software is
10 ** furnished to do so, subject to the following conditions:
11 **
12 ** The above copyright notice and this permission notice shall be included in
13 ** all copies or substantial portions of the Software.
14 **
15 ** THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 ** IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 ** FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 ** AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 ** LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20 ** OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
21 ** THE SOFTWARE.
22 **
23 ****************************************************************************/
24
25 #define _BSD_SOURCE 1
26 #define _DEFAULT_SOURCE 1
27 #define _GNU_SOURCE 1
28
29 #ifndef CBOR_WITHOUT_OPEN_MEMSTREAM
30
31 #include <sys/types.h>
32 #include <errno.h>
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <string.h>
36
37 #if defined(__unix__) || defined(__APPLE__)
38 # include <unistd.h>
39 #endif
40 #ifdef __APPLE__
41 typedef int RetType;
42 typedef int LenType;
43 #elif __GLIBC__
44 typedef ssize_t RetType;
45 typedef size_t LenType;
46 #else
47 # error "Cannot implement open_memstream!"
48 #endif
49
50 #include "tinycbor/compilersupport_p.h"
51
52 struct Buffer
53 {
54 char **ptr;
55 size_t *len;
56 size_t alloc;
57 };
58
write_to_buffer(void * cookie,const char * data,LenType len)59 static RetType write_to_buffer(void *cookie, const char *data, LenType len)
60 {
61 struct Buffer *b = (struct Buffer *)cookie;
62 char *ptr = *b->ptr;
63 size_t newsize;
64
65 errno = EFBIG;
66 if (unlikely(add_check_overflow(*b->len, len, &newsize)))
67 return -1;
68
69 if (newsize > b->alloc) {
70 // make room
71 size_t newalloc = newsize + newsize / 2 + 1; // give 50% more room
72 ptr = realloc(ptr, newalloc);
73 if (ptr == NULL)
74 return -1;
75 b->alloc = newalloc;
76 *b->ptr = ptr;
77 }
78
79 memcpy(ptr + *b->len, data, len);
80 *b->len = newsize;
81 return len;
82 }
83
close_buffer(void * cookie)84 static int close_buffer(void *cookie)
85 {
86 struct Buffer *b = (struct Buffer *)cookie;
87 if (*b->ptr)
88 (*b->ptr)[*b->len] = '\0';
89 free(b);
90 return 0;
91 }
92
open_memstream(char ** bufptr,size_t * lenptr)93 FILE *open_memstream(char **bufptr, size_t *lenptr)
94 {
95 struct Buffer *b = (struct Buffer *)malloc(sizeof(struct Buffer));
96 if (b == NULL)
97 return NULL;
98 b->alloc = 0;
99 b->len = lenptr;
100 b->ptr = bufptr;
101 *bufptr = NULL;
102 *lenptr = 0;
103
104 #ifdef __APPLE__
105 return funopen(b, NULL, write_to_buffer, NULL, close_buffer);
106 #elif __GLIBC__
107 static const cookie_io_functions_t vtable = {
108 NULL,
109 write_to_buffer,
110 NULL,
111 close_buffer
112 };
113 return fopencookie(b, "w", vtable);
114 #endif
115 }
116
117 #endif
118
