1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
3 *
4 * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 *
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 /**
30 * @file common.h
31 *
32 * @brief Common definitions and feature checks.
33 *
34 * @author Mike Becker
35 * @author Olaf Wintermann
36 * @copyright 2-Clause BSD License
37 *
38 * @mainpage UAP Common Extensions
39 * Library with common and useful functions, macros and data structures.
40 * <p>
41 * Latest available source:<br>
42 * <a href="https://sourceforge.net/projects/ucx/files/">https://sourceforge.net/projects/ucx/files/</a>
43 * </p>
44 *
45 * <p>
46 * Repositories:<br>
47 * <a href="https://sourceforge.net/p/ucx/code">https://sourceforge.net/p/ucx/code</a>
48 * - or -
49 * <a href="https://develop.uap-core.de/hg/ucx">https://develop.uap-core.de/hg/ucx</a>
50 * </p>
51 *
52 * <h2>LICENCE</h2>
53 *
54 * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved.
55 *
56 * Redistribution and use in source and binary forms, with or without
57 * modification, are permitted provided that the following conditions are met:
58 *
59 * 1. Redistributions of source code must retain the above copyright
60 * notice, this list of conditions and the following disclaimer.
61 *
62 * 2. Redistributions in binary form must reproduce the above copyright
63 * notice, this list of conditions and the following disclaimer in the
64 * documentation and/or other materials provided with the distribution.
65 *
66 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
67 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
68 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
69 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
70 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
71 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
72 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
73 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
74 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
75 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
76 * POSSIBILITY OF SUCH DAMAGE.
77 */
78
79 #ifndef UCX_COMMON_H
80 #define UCX_COMMON_H
81
82 /** Major UCX version as integer constant. */
83 #define UCX_VERSION_MAJOR 3
84
85 /** Minor UCX version as integer constant. */
86 #define UCX_VERSION_MINOR 1
87
88 /** Version constant which ensures to increase monotonically. */
89 #define UCX_VERSION (((UCX_VERSION_MAJOR)<<16)|UCX_VERSION_MINOR)
90
91 // ---------------------------------------------------------------------------
92 // Common includes
93 // ---------------------------------------------------------------------------
94
95 #include <stdlib.h>
96 #include <stddef.h>
97 #include <stdbool.h>
98 #include <stdint.h>
99 #include <sys/types.h>
100
101 // ---------------------------------------------------------------------------
102 // Architecture Detection
103 // ---------------------------------------------------------------------------
104
105 #ifndef INTPTR_MAX
106 #error Missing INTPTR_MAX definition
107 #endif
108 #if INTPTR_MAX == INT64_MAX
109 /**
110 * The address width in bits on this platform.
111 */
112 #define CX_WORDSIZE 64
113 #elif INTPTR_MAX == INT32_MAX
114 /**
115 * The address width in bits on this platform.
116 */
117 #define CX_WORDSIZE 32
118 #else
119 #error Unknown pointer size or missing size macros!
120 #endif
121
122 // ---------------------------------------------------------------------------
123 // Missing Defines
124 // ---------------------------------------------------------------------------
125
126 #ifndef SSIZE_MAX // not defined in glibc since C23 and MSVC
127 #if CX_WORDSIZE == 64
128 /**
129 * The maximum representable value in ssize_t.
130 */
131 #define SSIZE_MAX 0x7fffffffffffffffll
132 #else
133 #define SSIZE_MAX 0x7fffffffl
134 #endif
135 #endif
136
137
138 // ---------------------------------------------------------------------------
139 // Attribute definitions
140 // ---------------------------------------------------------------------------
141
142 #ifndef __GNUC__
143 /**
144 * Removes GNU C attributes where they are not supported.
145 */
146 #define __attribute__(x)
147 #endif
148
149 /**
150 * All pointer arguments must be non-NULL.
151 */
152 #define cx_attr_nonnull __attribute__((__nonnull__))
153
154 /**
155 * The specified pointer arguments must be non-NULL.
156 */
157 #define cx_attr_nonnull_arg(...) __attribute__((__nonnull__(__VA_ARGS__)))
158
159 /**
160 * The returned value is guaranteed to be non-NULL.
161 */
162 #define cx_attr_returns_nonnull __attribute__((__returns_nonnull__))
163
164 /**
165 * The attributed function always returns freshly allocated memory.
166 */
167 #define cx_attr_malloc __attribute__((__malloc__))
168
169 #ifndef __clang__
170 /**
171 * The pointer returned by the attributed function is supposed to be freed
172 * by @p freefunc.
173 *
174 * @param freefunc the function that shall be used to free the memory
175 * @param freefunc_arg the index of the pointer argument in @p freefunc
176 */
177 #define cx_attr_dealloc(freefunc, freefunc_arg) \
178 __attribute__((__malloc__(freefunc, freefunc_arg)))
179 #else
180 /**
181 * Not supported in clang.
182 */
183 #define cx_attr_dealloc(...)
184 #endif // __clang__
185
186 /**
187 * Shortcut to specify #cxFree() as deallocator.
188 */
189 #define cx_attr_dealloc_ucx cx_attr_dealloc(cxFree, 2)
190
191 /**
192 * Specifies the parameters from which the allocation size is calculated.
193 */
194 #define cx_attr_allocsize(...) __attribute__((__alloc_size__(__VA_ARGS__)))
195
196
197 #ifdef __clang__
198 /**
199 * No support for @c null_terminated_string_arg in clang or GCC below 14.
200 */
201 #define cx_attr_cstr_arg(idx)
202 /**
203 * No support for access attribute in clang.
204 */
205 #define cx_attr_access(mode, ...)
206 #else
207 #if __GNUC__ < 10
208 /**
209 * No support for access attribute in GCC < 10.
210 */
211 #define cx_attr_access(mode, ...)
212 #else
213 /**
214 * Helper macro to define access macros.
215 */
216 #define cx_attr_access(mode, ...) __attribute__((__access__(mode, __VA_ARGS__)))
217 #endif // __GNUC__ < 10
218 #if __GNUC__ < 14
219 /**
220 * No support for @c null_terminated_string_arg in clang or GCC below 14.
221 */
222 #define cx_attr_cstr_arg(idx)
223 #else
224 /**
225 * The specified argument is expected to be a zero-terminated string.
226 *
227 * @param idx the index of the argument
228 */
229 #define cx_attr_cstr_arg(idx) \
230 __attribute__((__null_terminated_string_arg__(idx)))
231 #endif // __GNUC__ < 14
232 #endif // __clang__
233
234
235 /**
236 * Specifies that the function will only read through the given pointer.
237 *
238 * Takes one or two arguments: the index of the pointer and (optionally) the
239 * index of another argument specifying the maximum number of accessed bytes.
240 */
241 #define cx_attr_access_r(...) cx_attr_access(__read_only__, __VA_ARGS__)
242
243 /**
244 * Specifies that the function will read and write through the given pointer.
245 *
246 * Takes one or two arguments: the index of the pointer and (optionally) the
247 * index of another argument specifying the maximum number of accessed bytes.
248 */
249 #define cx_attr_access_rw(...) cx_attr_access(__read_write__, __VA_ARGS__)
250
251 /**
252 * Specifies that the function will only write through the given pointer.
253 *
254 * Takes one or two arguments: the index of the pointer and (optionally) the
255 * index of another argument specifying the maximum number of accessed bytes.
256 */
257 #define cx_attr_access_w(...) cx_attr_access(__write_only__, __VA_ARGS__)
258
259 #if __STDC_VERSION__ >= 202300L
260
261 /**
262 * Do not warn about unused variable.
263 */
264 #define cx_attr_unused [[maybe_unused]]
265
266 /**
267 * Warn about discarded return value.
268 */
269 #define cx_attr_nodiscard [[nodiscard]]
270
271 #else // no C23
272
273 /**
274 * Do not warn about unused variable.
275 */
276 #define cx_attr_unused __attribute__((__unused__))
277
278 /**
279 * Warn about discarded return value.
280 */
281 #define cx_attr_nodiscard __attribute__((__warn_unused_result__))
282
283 #endif // __STDC_VERSION__
284
285 // ---------------------------------------------------------------------------
286 // Useful function pointers
287 // ---------------------------------------------------------------------------
288
289 /**
290 * Function pointer compatible with fwrite-like functions.
291 */
292 typedef size_t (*cx_write_func)(
293 const void *,
294 size_t,
295 size_t,
296 void *
297 );
298
299 /**
300 * Function pointer compatible with fread-like functions.
301 */
302 typedef size_t (*cx_read_func)(
303 void *,
304 size_t,
305 size_t,
306 void *
307 );
308
309 // ---------------------------------------------------------------------------
310 // Utility macros
311 // ---------------------------------------------------------------------------
312
313 /**
314 * Determines the number of members in a static C array.
315 *
316 * @attention never use this to determine the size of a dynamically allocated
317 * array.
318 *
319 * @param arr the array identifier
320 * @return the number of elements
321 */
322 #define cx_nmemb(arr) (sizeof(arr)/sizeof((arr)[0]))
323
324 // ---------------------------------------------------------------------------
325 // szmul implementation
326 // ---------------------------------------------------------------------------
327
328 #if (__GNUC__ >= 5 || defined(__clang__)) && !defined(CX_NO_SZMUL_BUILTIN)
329 #define CX_SZMUL_BUILTIN
330 #define cx_szmul(a, b, result) __builtin_mul_overflow(a, b, result)
331 #else // no GNUC or clang bultin
332 /**
333 * Performs a multiplication of size_t values and checks for overflow.
334 *
335 * @param a (@c size_t) first operand
336 * @param b (@c size_t) second operand
337 * @param result (@c size_t*) a pointer to a variable, where the result should
338 * be stored
339 * @retval zero success
340 * @retval non-zero the multiplication would overflow
341 */
342 #define cx_szmul(a, b, result) cx_szmul_impl(a, b, result)
343
344 /**
345 * Implementation of cx_szmul() when no compiler builtin is available.
346 *
347 * Do not use in application code.
348 *
349 * @param a first operand
350 * @param b second operand
351 * @param result a pointer to a variable, where the result should
352 * be stored
353 * @retval zero success
354 * @retval non-zero the multiplication would overflow
355 */
356 #if __cplusplus
357 extern "C"
358 #endif
359 int cx_szmul_impl(size_t a, size_t b, size_t *result);
360 #endif // cx_szmul
361
362
363 // ---------------------------------------------------------------------------
364 // Fixes for MSVC incompatibilities
365 // ---------------------------------------------------------------------------
366
367 #ifdef _MSC_VER
368 // fix missing ssize_t definition
369 #include <BaseTsd.h>
370 typedef SSIZE_T ssize_t;
371
372 // fix missing _Thread_local support
373 #define _Thread_local __declspec(thread)
374 #endif // _MSC_VER
375
376 #endif // UCX_COMMON_H
377