1 /* Test pthread_setname_np and pthread_getname_np.
2 Copyright (C) 2013-2023 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 License as
7 published by the Free Software Foundation; either version 2.1 of the
8 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; see the file COPYING.LIB. If
17 not, see <https://www.gnu.org/licenses/>. */
18 #include <stdio.h>
19 #include <stdlib.h>
20 #include <pthread.h>
21 #include <string.h>
22 #include <sys/syscall.h>
23 #include <unistd.h>
24 #include <fcntl.h>
25 #include <errno.h>
26
27 /* New name of process. */
28 #define NEW_NAME "setname"
29
30 /* Name of process which is one byte too big
31 e.g. 17 bytes including null-terminator */
32 #define BIG_NAME "....V....X....XV"
33
34 /* Longest name of a process
35 e.g. 16 bytes including null-terminator. */
36 #define LONGEST_NAME "....V....X....X"
37
38 /* One less than longest name with unique
39 characters to detect modification. */
40 #define CANARY_NAME "abcdefghijklmn"
41
42 /* On Linux the maximum length of the name of a task *including* the null
43 terminator. */
44 #define TASK_COMM_LEN 16
45
46 /* On Linux we can read this task's name from /proc. */
47 int
48 get_self_comm (long tid, char *buf, size_t len)
49 {
50 int res = 0;
51 #define FMT "/proc/self/task/%lu/comm"
52 char fname[sizeof (FMT) + 32];
53 sprintf (fname, FMT, (unsigned long) tid);
54
55 int fd = open (fname, O_RDONLY);
56 if (fd == -1)
57 return errno;
58
59 ssize_t n = read (fd, (void *) buf, len);
60 if (n < 0)
61 res = errno;
62 else
63 {
64 if (buf[n - 1] == '\n')
65 buf[n - 1] = '\0';
66 else if (n == len)
67 res = ERANGE;
68 else
69 buf[n] = '\0';
70 }
71
72 close (fd);
73 return res;
74 }
75
76 int
77 do_test (int argc, char **argv)
78 {
79 pthread_t self;
80 int res;
81 int ret = 0;
82 char name[TASK_COMM_LEN];
83 char name_check[TASK_COMM_LEN];
84
85 memset (name, '\0', TASK_COMM_LEN);
86 memset (name_check, '\0', TASK_COMM_LEN);
87
88 /* Test 1: Get the name of the task via pthread_getname_np and /proc
89 and verify that they both match. */
90 self = pthread_self ();
91 res = pthread_getname_np (self, name, TASK_COMM_LEN);
92
93 if (res == 0)
94 {
95 res = get_self_comm (gettid (), name_check, TASK_COMM_LEN);
96
97 if (res == 0)
98 {
99 if (strncmp (name, name_check, strlen (BIG_NAME)) == 0)
100 printf ("PASS: Test 1 - pthread_getname_np and /proc agree.\n");
101 else
102 {
103 printf ("FAIL: Test 1 - pthread_getname_np and /proc differ"
104 " i.e. %s != %s\n", name, name_check);
105 ret++;
106 }
107 }
108 else
109 {
110 printf ("FAIL: Test 1 - unable read task name via proc.\n");
111 ret++;
112 }
113 }
114 else
115 {
116 printf ("FAIL: Test 1 - pthread_getname_np failed with error %d\n", res);
117 ret++;
118 }
119
120 /* Test 2: Test setting the name and then independently verify it
121 was set. */
122 res = pthread_setname_np (self, NEW_NAME);
123
124 if (res == 0)
125 {
126 res = get_self_comm (gettid (), name_check, TASK_COMM_LEN);
127 if (res == 0)
128 {
129 if (strncmp (NEW_NAME, name_check, strlen (BIG_NAME)) == 0)
130 printf ("PASS: Test 2 - Value used in pthread_setname_np and"
131 " /proc agree.\n");
132 else
133 {
134 printf ("FAIL: Test 2 - Value used in pthread_setname_np"
135 " and /proc differ i.e. %s != %s\n",
136 NEW_NAME, name_check);
137 ret++;
138 }
139 }
140 else
141 {
142 printf ("FAIL: Test 2 - unable to read task name via proc.\n");
143 ret++;
144 }
145 }
146 else
147 {
148 printf ("FAIL: Test 2 - pthread_setname_np failed with error %d\n", res);
149 ret++;
150 }
151
152 /* Test 3: Test setting a name that is one-byte too big. */
153 res = pthread_getname_np (self, name, TASK_COMM_LEN);
154
155 if (res == 0)
156 {
157 res = pthread_setname_np (self, BIG_NAME);
158 if (res != 0)
159 {
160 if (res == ERANGE)
161 {
162 printf ("PASS: Test 3 - pthread_setname_np returned ERANGE"
163 " for a process name that was too long.\n");
164
165 /* Verify the old name didn't change. */
166 res = get_self_comm (gettid (), name_check, TASK_COMM_LEN);
167 if (res == 0)
168 {
169 if (strncmp (name, name_check, strlen (BIG_NAME)) == 0)
170 printf ("PASS: Test 3 - Original name unchanged after"
171 " pthread_setname_np returned ERANGE.\n");
172 else
173 {
174 printf ("FAIL: Test 3 - Original name changed after"
175 " pthread_setname_np returned ERANGE"
176 " i.e. %s != %s\n",
177 name, name_check);
178 ret++;
179 }
180 }
181 else
182 {
183 printf ("FAIL: Test 3 - unable to read task name.\n");
184 ret++;
185 }
186 }
187 else
188 {
189 printf ("FAIL: Test 3 - Wrong error returned"
190 " i.e. ERANGE != %d\n", res);
191 ret++;
192 }
193 }
194 else
195 {
196 printf ("FAIL: Test 3 - Too-long name accepted by"
197 " pthread_setname_np.\n");
198 ret++;
199 }
200 }
201 else
202 {
203 printf ("FAIL: Test 3 - Unable to get original name.\n");
204 ret++;
205 }
206
207 /* Test 4: Verify that setting the longest name works. */
208 res = pthread_setname_np (self, LONGEST_NAME);
209
210 if (res == 0)
211 {
212 res = get_self_comm (gettid (), name_check, TASK_COMM_LEN);
213 if (res == 0)
214 {
215 if (strncmp (LONGEST_NAME, name_check, strlen (BIG_NAME)) == 0)
216 printf ("PASS: Test 4 - Longest name set via pthread_setname_np"
217 " agrees with /proc.\n");
218 else
219 {
220 printf ("FAIL: Test 4 - Value used in pthread_setname_np and /proc"
221 " differ i.e. %s != %s\n", LONGEST_NAME, name_check);
222 ret++;
223 }
224 }
225 else
226 {
227 printf ("FAIL: Test 4 - unable to read task name via proc.\n");
228 ret++;
229 }
230 }
231 else
232 {
233 printf ("FAIL: Test 4 - pthread_setname_np failed with error %d\n", res);
234 ret++;
235 }
236
237 /* Test 5: Verify that getting a long name into a small buffer fails. */
238 strncpy (name, CANARY_NAME, strlen (CANARY_NAME) + 1);
239
240 /* Claim the buffer length is strlen (LONGEST_NAME). This is one character
241 too small to hold LONGEST_NAME *and* the null terminator. We should get
242 back ERANGE and name should be unmodified. */
243 res = pthread_getname_np (self, name, strlen (LONGEST_NAME));
244
245 if (res != 0)
246 {
247 if (res == ERANGE)
248 {
249 if (strncmp (CANARY_NAME, name, strlen (BIG_NAME)) == 0)
250 {
251 printf ("PASS: Test 5 - ERANGE and buffer unmodified.\n");
252 }
253 else
254 {
255 printf ("FAIL: Test 5 - Original buffer modified.\n");
256 ret++;
257 }
258 }
259 else
260 {
261 printf ("FAIL: Test 5 - Did not return ERANGE for small buffer.\n");
262 ret++;
263 }
264 }
265 else
266 {
267 printf ("FAIL: Test 5 - Returned name longer than buffer.\n");
268 ret++;
269 }
270
271 /* Test 6: Lastly make sure we can read back the longest name. */
272 res = pthread_getname_np (self, name, strlen (LONGEST_NAME) + 1);
273
274 if (res == 0)
275 {
276 if (strncmp (LONGEST_NAME, name, strlen (BIG_NAME)) == 0)
277 {
278 printf ("PASS: Test 6 - Read back longest name correctly.\n");
279 }
280 else
281 {
282 printf ("FAIL: Test 6 - Read \"%s\" instead of longest name.\n",
283 name);
284 ret++;
285 }
286 }
287 else
288 {
289 printf ("FAIL: Test 6 - pthread_getname_np failed with error %d\n", res);
290 ret++;
291 }
292
293 return ret;
294 }
295
296 #include <test-skeleton.c>