• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright (C) 2016 The Android Open Source Project
3  *
4  * Permission is hereby granted, free of charge, to any person
5  * obtaining a copy of this software and associated documentation
6  * files (the "Software"), to deal in the Software without
7  * restriction, including without limitation the rights to use, copy,
8  * modify, merge, publish, distribute, sublicense, and/or sell copies
9  * 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
13  * included in all copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
19  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
20  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22  * SOFTWARE.
23  */
24 
25 #if !defined(AVB_INSIDE_LIBAVB_H) && !defined(AVB_COMPILATION)
26 #error "Never include this file directly, include libavb.h instead."
27 #endif
28 
29 #ifndef AVB_UTIL_H_
30 #define AVB_UTIL_H_
31 
32 #include "avb_sysdeps.h"
33 
34 #ifdef __cplusplus
35 extern "C" {
36 #endif
37 
38 #define AVB_STRINGIFY(x) #x
39 #define AVB_TO_STRING(x) AVB_STRINGIFY(x)
40 
41 #ifdef AVB_ENABLE_DEBUG
42 /* Aborts the program if |expr| is false.
43  *
44  * This has no effect unless AVB_ENABLE_DEBUG is defined.
45  */
46 #define avb_assert(expr)                     \
47   do {                                       \
48     if (!(expr)) {                           \
49       avb_fatal("assert fail: " #expr "\n"); \
50     }                                        \
51   } while (0)
52 #else
53 #define avb_assert(expr)
54 #endif
55 
56 /* Aborts the program if reached.
57  *
58  * This has no effect unless AVB_ENABLE_DEBUG is defined.
59  */
60 #ifdef AVB_ENABLE_DEBUG
61 #define avb_assert_not_reached()         \
62   do {                                   \
63     avb_fatal("assert_not_reached()\n"); \
64   } while (0)
65 #else
66 #define avb_assert_not_reached()
67 #endif
68 
69 /* Aborts the program if |addr| is not word-aligned.
70  *
71  * This has no effect unless AVB_ENABLE_DEBUG is defined.
72  */
73 #define avb_assert_aligned(addr) \
74   avb_assert((((uintptr_t)addr) & (AVB_ALIGNMENT_SIZE - 1)) == 0)
75 
76 #ifdef AVB_ENABLE_DEBUG
77 /* Print functions, used for diagnostics.
78  *
79  * These have no effect unless AVB_ENABLE_DEBUG is defined.
80  */
81 #define avb_debug(message)              \
82   do {                                  \
83     avb_printv(avb_basename(__FILE__),  \
84                ":",                     \
85                AVB_TO_STRING(__LINE__), \
86                ": DEBUG: ",             \
87                message,                 \
88                NULL);                   \
89   } while (0)
90 #define avb_debugv(message, ...)        \
91   do {                                  \
92     avb_printv(avb_basename(__FILE__),  \
93                ":",                     \
94                AVB_TO_STRING(__LINE__), \
95                ": DEBUG: ",             \
96                message,                 \
97                ##__VA_ARGS__);          \
98   } while (0)
99 #else
100 #define avb_debug(message)
101 #define avb_debugv(message, ...)
102 #endif
103 
104 /* Prints out a message. This is typically used if a runtime-error
105  * occurs.
106  */
107 #define avb_error(message)              \
108   do {                                  \
109     avb_printv(avb_basename(__FILE__),  \
110                ":",                     \
111                AVB_TO_STRING(__LINE__), \
112                ": ERROR: ",             \
113                message,                 \
114                NULL);                   \
115   } while (0)
116 #define avb_errorv(message, ...)        \
117   do {                                  \
118     avb_printv(avb_basename(__FILE__),  \
119                ":",                     \
120                AVB_TO_STRING(__LINE__), \
121                ": ERROR: ",             \
122                message,                 \
123                ##__VA_ARGS__);          \
124   } while (0)
125 
126 /* Prints out a message and calls avb_abort().
127  */
128 #define avb_fatal(message)              \
129   do {                                  \
130     avb_printv(avb_basename(__FILE__),  \
131                ":",                     \
132                AVB_TO_STRING(__LINE__), \
133                ": FATAL: ",             \
134                message,                 \
135                NULL);                   \
136     avb_abort();                        \
137   } while (0)
138 #define avb_fatalv(message, ...)        \
139   do {                                  \
140     avb_printv(avb_basename(__FILE__),  \
141                ":",                     \
142                AVB_TO_STRING(__LINE__), \
143                ": FATAL: ",             \
144                message,                 \
145                ##__VA_ARGS__);          \
146     avb_abort();                        \
147   } while (0)
148 
149 /* Converts a 32-bit unsigned integer from big-endian to host byte order. */
150 uint32_t avb_be32toh(uint32_t in) AVB_ATTR_WARN_UNUSED_RESULT;
151 
152 /* Converts a 64-bit unsigned integer from big-endian to host byte order. */
153 uint64_t avb_be64toh(uint64_t in) AVB_ATTR_WARN_UNUSED_RESULT;
154 
155 /* Converts a 32-bit unsigned integer from host to big-endian byte order. */
156 uint32_t avb_htobe32(uint32_t in) AVB_ATTR_WARN_UNUSED_RESULT;
157 
158 /* Converts a 64-bit unsigned integer from host to big-endian byte order. */
159 uint64_t avb_htobe64(uint64_t in) AVB_ATTR_WARN_UNUSED_RESULT;
160 
161 /* Compare |n| bytes starting at |s1| with |s2| and return 0 if they
162  * match, 1 if they don't.  Returns 0 if |n|==0, since no bytes
163  * mismatched.
164  *
165  * Time taken to perform the comparison is only dependent on |n| and
166  * not on the relationship of the match between |s1| and |s2|.
167  *
168  * Note that unlike avb_memcmp(), this only indicates inequality, not
169  * whether |s1| is less than or greater than |s2|.
170  */
171 int avb_safe_memcmp(const void* s1,
172                     const void* s2,
173                     size_t n) AVB_ATTR_WARN_UNUSED_RESULT;
174 
175 /* Adds |value_to_add| to |value| with overflow protection.
176  *
177  * Returns false if the addition overflows, true otherwise. In either
178  * case, |value| is always modified.
179  */
180 bool avb_safe_add_to(uint64_t* value,
181                      uint64_t value_to_add) AVB_ATTR_WARN_UNUSED_RESULT;
182 
183 /* Adds |a| and |b| with overflow protection, returning the value in
184  * |out_result|.
185  *
186  * It's permissible to pass NULL for |out_result| if you just want to
187  * check that the addition would not overflow.
188  *
189  * Returns false if the addition overflows, true otherwise.
190  */
191 bool avb_safe_add(uint64_t* out_result,
192                   uint64_t a,
193                   uint64_t b) AVB_ATTR_WARN_UNUSED_RESULT;
194 
195 /* Checks if |num_bytes| data at |data| is a valid UTF-8
196  * string. Returns true if valid UTF-8, false otherwise.
197  */
198 bool avb_validate_utf8(const uint8_t* data,
199                        size_t num_bytes) AVB_ATTR_WARN_UNUSED_RESULT;
200 
201 /* Concatenates |str1| (of |str1_len| bytes) and |str2| (of |str2_len|
202  * bytes) and puts the result in |buf| which holds |buf_size|
203  * bytes. The result is also guaranteed to be NUL terminated. Fail if
204  * there is not enough room in |buf| for the resulting string plus
205  * terminating NUL byte.
206  *
207  * Returns true if the operation succeeds, false otherwise.
208  */
209 bool avb_str_concat(char* buf,
210                     size_t buf_size,
211                     const char* str1,
212                     size_t str1_len,
213                     const char* str2,
214                     size_t str2_len);
215 
216 /* Like avb_malloc_() but prints a error using avb_error() if memory
217  * allocation fails.
218  */
219 void* avb_malloc(size_t size) AVB_ATTR_WARN_UNUSED_RESULT;
220 
221 /* Like avb_malloc() but sets the memory with zeroes. */
222 void* avb_calloc(size_t size) AVB_ATTR_WARN_UNUSED_RESULT;
223 
224 /* Duplicates a NUL-terminated string. Returns NULL on OOM. */
225 char* avb_strdup(const char* str) AVB_ATTR_WARN_UNUSED_RESULT;
226 
227 /* Duplicates a NULL-terminated array of NUL-terminated strings by
228  * concatenating them. The returned string will be
229  * NUL-terminated. Returns NULL on OOM.
230  */
231 char* avb_strdupv(const char* str,
232                   ...) AVB_ATTR_WARN_UNUSED_RESULT AVB_ATTR_SENTINEL;
233 
234 /* Finds the first occurrence of |needle| in the string |haystack|
235  * where both strings are NUL-terminated strings. The terminating NUL
236  * bytes are not compared.
237  *
238  * Returns NULL if not found, otherwise points into |haystack| for the
239  * first occurrence of |needle|.
240  */
241 const char* avb_strstr(const char* haystack,
242                        const char* needle) AVB_ATTR_WARN_UNUSED_RESULT;
243 
244 /* Finds the first occurrence of |str| in the NULL-terminated string
245  * array |strings|. Each element in |strings| must be
246  * NUL-terminated. The string given by |str| need not be
247  * NUL-terminated but its size must be given in |str_size|.
248  *
249  * Returns NULL if not found, otherwise points into |strings| for the
250  * first occurrence of |str|.
251  */
252 const char* avb_strv_find_str(const char* const* strings,
253                               const char* str,
254                               size_t str_size);
255 
256 /* Replaces all occurrences of |search| with |replace| in |str|.
257  *
258  * Returns a newly allocated string or NULL if out of memory.
259  */
260 char* avb_replace(const char* str,
261                   const char* search,
262                   const char* replace) AVB_ATTR_WARN_UNUSED_RESULT;
263 
264 /* Calculates the CRC-32 for data in |buf| of size |buf_size|. */
265 uint32_t avb_crc32(const uint8_t* buf, size_t buf_size);
266 
267 /* Returns the basename of |str|. This is defined as the last path
268  * component, assuming the normal POSIX separator '/'. If there are no
269  * separators, returns |str|.
270  */
271 const char* avb_basename(const char* str);
272 
273 #ifdef __cplusplus
274 }
275 #endif
276 
277 #endif /* AVB_UTIL_H_ */
278