1 /*
2  * Copyright © 2020 Intel Corporation
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * 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
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21  * IN THE SOFTWARE.
22  */
23 
24 #ifndef U_QSORT_H
25 #define U_QSORT_H
26 
27 #include <stdlib.h>
28 
29 #include "detect_os.h"
30 
31 #ifdef __cplusplus
32 extern "C" {
33 #endif
34 
35 void util_tls_qsort_r(void *base, size_t nmemb, size_t size,
36                       int (*compar)(const void *, const void *, void *),
37                       void *arg);
38 
39 
40 struct util_qsort_adapter_data {
41    int (*compar)(const void*, const void*, void*);
42    void *args;
43 };
44 
45 /**
46  * Converts comparison function arguments
47  * from [MSVC, BSD, macOS]
48  * (void *ctx, const void *elem1, const void *elem2)
49  * to [GNU, C11]
50  * (const void *elem1, const void *elem2, void *ctx);
51  */
52 int util_qsort_adapter(void *ctx, const void *elem1, const void *elem2);
53 
54 static inline void
util_qsort_r(void * base,size_t nmemb,size_t size,int (* compar)(const void *,const void *,void *),void * arg)55 util_qsort_r(void *base, size_t nmemb, size_t size,
56              int (*compar)(const void *, const void *, void *),
57              void *arg)
58 {
59 #if defined(HAVE_GNU_QSORT_R)
60    /* GNU extension added in glibc 2.8 */
61    qsort_r(base, nmemb, size, compar, arg);
62 #elif defined(HAVE_BSD_QSORT_R)
63    /* BSD/macOS qsort_r takes "arg" before the comparison function and it
64     * pass the "arg" before the elements.
65     */
66    struct util_qsort_adapter_data data = {
67       compar,
68       arg
69    };
70    qsort_r(base, nmemb, size, &data, util_qsort_adapter);
71 #elif HAVE_QSORT_S
72 #  ifdef _WIN32
73    /* MSVC/MinGW qsort_s takes "arg" after the comparison function and it
74     * pass the "arg" before the elements.
75     */
76    struct util_qsort_adapter_data data = {
77       compar,
78       arg
79    };
80    qsort_s(base, nmemb, size, util_qsort_adapter, &data);
81 #  else
82    /* C11 added qsort_s */
83    qsort_s(base, nmemb, size, compar, arg);
84 #  endif
85 #else
86    /* Fall-back to using thread local storage */
87    util_tls_qsort_r(base, nmemb, size, compar, arg);
88 #endif
89 }
90 
91 #ifdef __cplusplus
92 } /* extern "C" */
93 #endif
94 
95 #endif /* U_QSORT_H */
96