1 | /* Test the allocate_once function. |
2 | Copyright (C) 2018-2022 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 of the License, or (at your option) any later version. |
9 | |
10 | The GNU C Library is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | Lesser General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU Lesser General Public |
16 | License along with the GNU C Library; if not, see |
17 | <https://www.gnu.org/licenses/>. */ |
18 | |
19 | #include <allocate_once.h> |
20 | #include <mcheck.h> |
21 | #include <string.h> |
22 | #include <support/check.h> |
23 | #include <support/support.h> |
24 | |
25 | /* Allocate a new string. */ |
26 | static void * |
27 | allocate_string (void *closure) |
28 | { |
29 | return xstrdup (closure); |
30 | } |
31 | |
32 | /* Allocation and deallocation functions which are not expected to be |
33 | called. */ |
34 | |
35 | static void * |
36 | allocate_not_called (void *closure) |
37 | { |
38 | FAIL_EXIT1 ("allocation function called unexpectedly (%p)" , closure); |
39 | } |
40 | |
41 | static void |
42 | deallocate_not_called (void *closure, void *ptr) |
43 | { |
44 | FAIL_EXIT1 ("deallocate function called unexpectedly (%p, %p)" , |
45 | closure, ptr); |
46 | } |
47 | |
48 | /* Counter for various function calls. */ |
49 | static int function_called; |
50 | |
51 | /* An allocation function which returns NULL and records that it has |
52 | been called. */ |
53 | static void * |
54 | allocate_return_null (void *closure) |
55 | { |
56 | /* The function should only be called once. */ |
57 | TEST_COMPARE (function_called, 0); |
58 | ++function_called; |
59 | return NULL; |
60 | } |
61 | |
62 | |
63 | /* The following is used to check the retry logic, by causing a fake |
64 | race condition. */ |
65 | static void *fake_race_place; |
66 | static char fake_race_region[3]; /* To obtain unique addresses. */ |
67 | |
68 | static void * |
69 | fake_race_allocate (void *closure) |
70 | { |
71 | TEST_VERIFY (closure == &fake_race_region[0]); |
72 | TEST_COMPARE (function_called, 0); |
73 | ++function_called; |
74 | /* Fake allocation by another thread. */ |
75 | fake_race_place = &fake_race_region[1]; |
76 | return &fake_race_region[2]; |
77 | } |
78 | |
79 | static void |
80 | fake_race_deallocate (void *closure, void *ptr) |
81 | { |
82 | /* Check that the pointer returned from fake_race_allocate is |
83 | deallocated (and not the one stored in fake_race_place). */ |
84 | TEST_VERIFY (ptr == &fake_race_region[2]); |
85 | |
86 | TEST_VERIFY (fake_race_place == &fake_race_region[1]); |
87 | TEST_VERIFY (closure == &fake_race_region[0]); |
88 | TEST_COMPARE (function_called, 1); |
89 | ++function_called; |
90 | } |
91 | |
92 | /* Similar to fake_race_allocate, but expects to be paired with free |
93 | as the deallocation function. */ |
94 | static void * |
95 | fake_race_allocate_for_free (void *closure) |
96 | { |
97 | TEST_VERIFY (closure == &fake_race_region[0]); |
98 | TEST_COMPARE (function_called, 0); |
99 | ++function_called; |
100 | /* Fake allocation by another thread. */ |
101 | fake_race_place = &fake_race_region[1]; |
102 | return xstrdup ("to be freed" ); |
103 | } |
104 | |
105 | static int |
106 | do_test (void) |
107 | { |
108 | mtrace (); |
109 | |
110 | /* Simple allocation. */ |
111 | void *place1 = NULL; |
112 | char *string1 = allocate_once (place: &place1, allocate: allocate_string, |
113 | deallocate: deallocate_not_called, |
114 | closure: (char *) "test string 1" ); |
115 | TEST_VERIFY_EXIT (string1 != NULL); |
116 | TEST_VERIFY (strcmp ("test string 1" , string1) == 0); |
117 | /* Second call returns the first pointer, without calling any |
118 | callbacks. */ |
119 | TEST_VERIFY (string1 |
120 | == allocate_once (&place1, allocate_not_called, |
121 | deallocate_not_called, |
122 | (char *) "test string 1a" )); |
123 | |
124 | /* Different place should result in another call. */ |
125 | void *place2 = NULL; |
126 | char *string2 = allocate_once (place: &place2, allocate: allocate_string, |
127 | deallocate: deallocate_not_called, |
128 | closure: (char *) "test string 2" ); |
129 | TEST_VERIFY_EXIT (string2 != NULL); |
130 | TEST_VERIFY (strcmp ("test string 2" , string2) == 0); |
131 | TEST_VERIFY (string1 != string2); |
132 | |
133 | /* Check error reporting (NULL return value from the allocation |
134 | function). */ |
135 | void *place3 = NULL; |
136 | char *string3 = allocate_once (place: &place3, allocate: allocate_return_null, |
137 | deallocate: deallocate_not_called, NULL); |
138 | TEST_VERIFY (string3 == NULL); |
139 | TEST_COMPARE (function_called, 1); |
140 | |
141 | /* Check that the deallocation function is called if the race is |
142 | lost. */ |
143 | function_called = 0; |
144 | TEST_VERIFY (allocate_once (&fake_race_place, |
145 | fake_race_allocate, |
146 | fake_race_deallocate, |
147 | &fake_race_region[0]) |
148 | == &fake_race_region[1]); |
149 | TEST_COMPARE (function_called, 2); |
150 | function_called = 3; |
151 | TEST_VERIFY (allocate_once (&fake_race_place, |
152 | fake_race_allocate, |
153 | fake_race_deallocate, |
154 | &fake_race_region[0]) |
155 | == &fake_race_region[1]); |
156 | TEST_COMPARE (function_called, 3); |
157 | |
158 | /* Similar, but this time rely on that free is called. */ |
159 | function_called = 0; |
160 | fake_race_place = NULL; |
161 | TEST_VERIFY (allocate_once (&fake_race_place, |
162 | fake_race_allocate_for_free, |
163 | NULL, |
164 | &fake_race_region[0]) |
165 | == &fake_race_region[1]); |
166 | TEST_COMPARE (function_called, 1); |
167 | function_called = 3; |
168 | TEST_VERIFY (allocate_once (&fake_race_place, |
169 | fake_race_allocate_for_free, |
170 | NULL, |
171 | &fake_race_region[0]) |
172 | == &fake_race_region[1]); |
173 | TEST_COMPARE (function_called, 3); |
174 | |
175 | free (ptr: place2); |
176 | free (ptr: place1); |
177 | |
178 | return 0; |
179 | } |
180 | |
181 | #include <support/test-driver.c> |
182 | |