1 /*
2  * Copyright (c) 2022 Huawei Device Co., Ltd.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at
6  *
7  *     http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 
16 #include <pthread.h>
17 #include <stdio.h>
18 #include <stdlib.h>
19 #include <string.h>
20 #include "test.h"
21 
22 static FILE *fp;
23 const char *path = "/data/test.txt";
24 
do_child_one(void *a)25 void *do_child_one(void *a)
26 {
27     puts("start do_child_one");
28 
29     flockfile(stdout);
30 
31     puts("after first flockfile");
32 
33     flockfile(stdout);
34 
35     puts("foo");
36 
37     funlockfile(stdout);
38 
39     puts("after first funlockfile");
40 
41     funlockfile(stdout);
42 
43     puts("all done");
44     return a;
45 }
46 
do_child_two(void *p)47 void *do_child_two(void *p)
48 {
49     char buf[64];
50 
51     flockfile(fp);
52 
53     if (fseek(fp, 0L, SEEK_SET) == -1) {
54         t_error("%s fseek failed\n", __func__);
55     }
56     int ret = fread(buf, 64, 1, fp);
57 
58     int count = atoi(buf);
59     ++count;
60     sprintf(buf, "%d", count);
61     if (fseek(fp, 0L, SEEK_SET) == -1) {
62         t_error("%s fseek failed\n", __func__);
63     }
64     ret = fwrite(buf, strlen(buf), 1, fp);
65 
66     funlockfile(fp);
67     return NULL;
68 }
69 
70 /**
71  * @tc.name      : flockfile_0100
72  * @tc.desc      : Acquire for a thread ownership of a (FILE *) object (stdout)
73  * @tc.level     : Level 0
74  */
flockfile_0100(void)75 void flockfile_0100(void)
76 {
77     pthread_t th;
78 
79     if (pthread_create(&th, NULL, do_child_one, NULL) != 0) {
80         t_error("%s pthread_create failed\n", __func__);
81     }
82 
83     void *result;
84     if (pthread_join(th, &result) != 0) {
85         t_error("%s pthread_join failed\n", __func__);
86     } else if (result != NULL) {
87         t_error("%s wrong return value: %p, expected %p\n", __func__, result, NULL);
88     }
89 }
90 
91 /**
92  * @tc.name      : flockfile_0200
93  * @tc.desc      : Shared FILE* to implements mutual exclusion
94  * @tc.level     : Level 1
95  */
flockfile_0200(void)96 void flockfile_0200(void)
97 {
98     pthread_t tid[100];
99 
100     fp = fopen(path, "w+");
101     if (fp == NULL) {
102         t_error("%s fopen failed\n", __func__);
103     }
104 
105     for (int i = 0; i < 100; i++) {
106         if (pthread_create(tid + i, NULL, do_child_two, NULL) != 0) {
107             t_error("%s pthread_create failed\n", __func__);
108         }
109     }
110 
111     for (int j = 0; j < 100; j++) {
112         if (pthread_join(tid[j], NULL) != 0) {
113             t_error("%s pthread_join failed\n", __func__);
114         }
115     }
116 
117     fclose(fp);
118     remove(path);
119 }
120 
main(int argc, char *argv[])121 int main(int argc, char *argv[])
122 {
123     flockfile_0100();
124     flockfile_0200();
125     return t_status;
126 }