1 /* Test and measure memmem functions.
2    Copyright (C) 2008-2022 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 #define TEST_MAIN
20 #define TEST_NAME "memmem"
21 #define BUF1PAGES 20
22 #define ITERATIONS 500
23 #include "test-string.h"
24 
25 typedef char *(*proto_t) (const void *, size_t, const void *, size_t);
26 
27 IMPL (memmem, 1)
28 
29 /* Naive implementation to verify results.  */
30 void *
simple_memmem(const void * haystack,size_t haystack_len,const void * needle,size_t needle_len)31 simple_memmem (const void *haystack, size_t haystack_len, const void *needle,
32 	       size_t needle_len)
33 {
34   const char *begin;
35   const char *const last_possible
36     = (const char *) haystack + haystack_len - needle_len;
37 
38   if (needle_len == 0)
39     /* The first occurrence of the empty string is deemed to occur at
40        the beginning of the string.  */
41     return (void *) haystack;
42 
43   /* Sanity check, otherwise the loop might search through the whole
44      memory.  */
45   if (__glibc_unlikely (haystack_len < needle_len))
46     return NULL;
47 
48   for (begin = (const char *) haystack; begin <= last_possible; ++begin)
49     if (begin[0] == ((const char *) needle)[0]
50         && !memcmp ((const void *) &begin[1],
51 		    (const void *) ((const char *) needle + 1),
52 		    needle_len - 1))
53       return (void *) begin;
54 
55   return NULL;
56 }
57 
58 static int
check_result(impl_t * impl,const void * haystack,size_t haystack_len,const void * needle,size_t needle_len,const void * expected)59 check_result (impl_t *impl, const void *haystack, size_t haystack_len,
60 	     const void *needle, size_t needle_len, const void *expected)
61 {
62   void *res;
63 
64   res = CALL (impl, haystack, haystack_len, needle, needle_len);
65   if (res != expected)
66     {
67       error (0, 0, "Wrong result in function %s %p %p", impl->name,
68 	     res, expected);
69       ret = 1;
70       return -1;
71     }
72 
73   return 0;
74 }
75 
76 static void
do_one_test(impl_t * impl,const void * haystack,size_t haystack_len,const void * needle,size_t needle_len,const void * expected)77 do_one_test (impl_t *impl, const void *haystack, size_t haystack_len,
78 	     const void *needle, size_t needle_len, const void *expected)
79 {
80   if (check_result (impl, haystack, haystack_len, needle, needle_len,
81 		    expected) < 0)
82     return;
83 }
84 
85 static void
do_test(const char * str,size_t len,size_t idx)86 do_test (const char *str, size_t len, size_t idx)
87 {
88   char tmpbuf[len];
89 
90   memcpy (tmpbuf, buf1 + idx, len);
91   memcpy (buf1 + idx, str, len);
92 
93   FOR_EACH_IMPL (impl, 0)
94     do_one_test (impl, buf1, BUF1PAGES * page_size, str, len, buf1 + idx);
95 
96   memcpy (buf1 + idx, tmpbuf, len);
97 }
98 
99 static void
do_random_tests(void)100 do_random_tests (void)
101 {
102   for (size_t n = 0; n < ITERATIONS; ++n)
103     {
104       char tmpbuf[32];
105 
106       size_t shift = random () % 11;
107       size_t rel = random () % ((2 << (shift + 1)) * 64);
108       size_t idx = MIN ((2 << shift) * 64 + rel, BUF1PAGES * page_size - 2);
109       size_t len = random () % (sizeof (tmpbuf) - 1) + 1;
110       len = MIN (len, BUF1PAGES * page_size - idx - 1);
111       memcpy (tmpbuf, buf1 + idx, len);
112       for (size_t i = random () % len / 2 + 1; i > 0; --i)
113 	{
114 	  size_t off = random () % len;
115 	  char ch = '0' + random () % 10;
116 
117 	  buf1[idx + off] = ch;
118 	}
119 
120       FOR_EACH_IMPL (impl, 0)
121 	do_one_test (impl, buf1, BUF1PAGES * page_size, buf1 + idx, len,
122 		     buf1 + idx);
123 
124       memcpy (buf1 + idx, tmpbuf, len);
125     }
126 }
127 
128 static void
check1(void)129 check1 (void)
130 {
131 
132   const char search_buf_data[5] = { 0x56, 0x34, 0x12, 0x78, 0x78 };
133   const char pattern[2] = { 0x78, 0x56 };
134   void *search_buf = (void *) buf1 + page_size - sizeof search_buf_data;
135   void *exp_result;
136 
137   memcpy (search_buf, search_buf_data, sizeof search_buf_data);
138   exp_result = simple_memmem (search_buf, sizeof search_buf_data,
139 			      pattern, sizeof pattern);
140   FOR_EACH_IMPL (impl, 0)
141     check_result (impl, search_buf, sizeof search_buf_data,
142 		  pattern, sizeof pattern, exp_result);
143 }
144 
145 static const char *const strs[] =
146   {
147     "00000", "00112233", "0123456789", "0000111100001111",
148     "00000111110000022222", "012345678901234567890",
149     "abc0", "aaaa0", "abcabc0"
150   };
151 
152 
153 int
test_main(void)154 test_main (void)
155 {
156   size_t i;
157 
158   test_init ();
159 
160   check1 ();
161 
162   printf ("%23s", "");
163   FOR_EACH_IMPL (impl, 0)
164     printf ("\t%s", impl->name);
165   putchar ('\n');
166 
167   for (i = 0; i < BUF1PAGES * page_size; ++i)
168     buf1[i] = 60 + random () % 32;
169 
170   for (i = 0; i < sizeof (strs) / sizeof (strs[0]); ++i)
171     for (size_t j = 0; j < 120; j += 7)
172       {
173 	size_t len = strlen (strs[i]);
174 
175 	do_test (strs[i], len, j);
176       }
177 
178   do_random_tests ();
179   return ret;
180 }
181 
182 #include <support/test-driver.c>
183