1 /* Test for fgetsgent_r and buffer sizes.
2 Copyright (C) 2020-2023 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
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 <array_length.h>
20 #include <errno.h>
21 #include <gshadow.h>
22 #include <stdbool.h>
23 #include <stdlib.h>
24 #include <support/check.h>
25 #include <support/support.h>
26 #include <support/temp_file.h>
27 #include <support/xmemstream.h>
28 #include <support/xstdio.h>
29
30 /* Turn a parsed struct back into a line string. The returned string
31 should be freed. */
32 static char *
33 format_ent (const struct sgrp *e)
34 {
35 struct xmemstream stream;
36 xopen_memstream (&stream);
37 TEST_COMPARE (putsgent (e, stream.out), 0);
38 xfclose_memstream (&stream);
39 return stream.buffer;
40 }
41
42 /* An entry in the input file along with the expected output. */
43 struct input
44 {
45 const char *line; /* Line in the file. */
46 const char *expected; /* Expected output. NULL if skipped. */
47 };
48
49 const struct input inputs[] =
50 {
51 /* Regular entries. */
52 { "g1:x1::\n", "g1:x1::\n" },
53 { "g2:x2:a1:\n", "g2:x2:a1:\n" },
54 { "g3:x3:a2:u1\n", "g3:x3:a2:u1\n" },
55 { "g4:x4:a3,a4:u2,u3,u4\n", "g4:x4:a3,a4:u2,u3,u4\n" },
56
57 /* Comments and empty lines. */
58 { "\n", NULL },
59 { " \n", NULL },
60 { "\t\n", NULL },
61 { "#g:x::\n", NULL },
62 { " #g:x::\n", NULL },
63 { "\t#g:x::\n", NULL },
64 { " \t#g:x::\n", NULL },
65
66 /* Marker for synchronization. */
67 { "g5:x5::\n", "g5:x5::\n" },
68
69 /* Leading whitespace. */
70 { " g6:x6::\n", "g6:x6::\n" },
71 { "\tg7:x7::\n", "g7:x7::\n" },
72
73 /* This is expected to trigger buffer exhaustion during parsing
74 (bug 20338). */
75 {
76 "g8:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx:u5,u6,u7,u8,u9:\n",
77 "g8:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx:u5,u6,u7,u8,u9:\n",
78 },
79 {
80 "g9:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx::a5,a6,a7,a8,a9,a10\n",
81 "g9:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx::a5,a6,a7,a8,a9,a10\n",
82 },
83 };
84
85 /* Writes the test data to a temporary file and returns its name. The
86 returned pointer should be freed. */
87 static char *
88 create_test_file (void)
89 {
90 char *path;
91 int fd = create_temp_file ("tst-fgetsgent_r-", &path);
92 FILE *fp = fdopen (fd, "w");
93 TEST_VERIFY_EXIT (fp != NULL);
94
95 for (size_t i = 0; i < array_length (inputs); ++i)
96 fputs (inputs[i].line, fp);
97
98 xfclose (fp);
99 return path;
100 }
101
102 /* Read the test file with the indicated start buffer size. Return
103 true if the buffer size had to be increased during reading. */
104 static bool
105 run_test (const char *path, size_t buffer_size)
106 {
107 bool resized = false;
108 FILE *fp = xfopen (path, "r");
109
110 /* This avoids repeated lseek system calls (bug 26257). */
111 TEST_COMPARE (fseeko64 (fp, 0, SEEK_SET), 0);
112
113 size_t i = 0;
114 while (true)
115 {
116 /* Skip over unused expected entries. */
117 while (i < array_length (inputs) && inputs[i].expected == NULL)
118 ++i;
119
120 /* Store the data on the heap, to help valgrind to detect
121 invalid accesses. */
122 struct sgrp *result_storage = xmalloc (sizeof (*result_storage));
123 char *buffer = xmalloc (buffer_size);
124 struct sgrp **result_pointer_storage
125 = xmalloc (sizeof (*result_pointer_storage));
126
127 int ret = fgetsgent_r (fp, result_storage, buffer, buffer_size,
128 result_pointer_storage);
129 if (ret == 0)
130 {
131 TEST_VERIFY (*result_pointer_storage != NULL);
132 TEST_VERIFY (i < array_length (inputs));
133 if (*result_pointer_storage != NULL
134 && i < array_length (inputs))
135 {
136 char * actual = format_ent (*result_pointer_storage);
137 TEST_COMPARE_STRING (inputs[i].expected, actual);
138 free (actual);
139 ++i;
140 }
141 else
142 break;
143 }
144 else
145 {
146 TEST_VERIFY (*result_pointer_storage == NULL);
147 TEST_COMPARE (ret, errno);
148
149 if (ret == ENOENT)
150 {
151 TEST_COMPARE (i, array_length (inputs));
152 free (result_pointer_storage);
153 free (buffer);
154 free (result_storage);
155 break;
156 }
157 else if (ret == ERANGE)
158 {
159 resized = true;
160 ++buffer_size;
161 }
162 else
163 FAIL_EXIT1 ("read failure: %m");
164 }
165
166 free (result_pointer_storage);
167 free (buffer);
168 free (result_storage);
169 }
170
171 xfclose (fp);
172 return resized;
173 }
174
175 static int
176 do_test (void)
177 {
178 char *path = create_test_file ();
179
180 for (size_t buffer_size = 3; ; ++buffer_size)
181 {
182 bool resized = run_test (path, buffer_size);
183 if (!resized)
184 break;
185 }
186
187 free (path);
188
189 return 0;
190 }
191
192 #include <support/test-driver.c>