1 /* A minor test-program for memmove.
2    Copyright (C) 2005 Axis Communications.
3    All rights reserved.
4 
5    Redistribution and use in source and binary forms, with or without
6    modification, are permitted provided that the following conditions
7    are met:
8 
9    1. Redistributions of source code must retain the above copyright
10       notice, this list of conditions and the following disclaimer.
11 
12    2. Neither the name of Axis Communications nor the names of its
13       contributors may be used to endorse or promote products derived
14       from this software without specific prior written permission.
15 
16    THIS SOFTWARE IS PROVIDED BY AXIS COMMUNICATIONS AND ITS CONTRIBUTORS
17    ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL AXIS
20    COMMUNICATIONS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
21    INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22    (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
23    SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24    HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
25    STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
26    IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27    POSSIBILITY OF SUCH DAMAGE.  */
28 
29 /* Test moves of 0..MAX bytes; overlapping-src-higher,
30    overlapping-src-lower and non-overlapping.  The overlap varies with
31    1..N where N is the size moved.  This means an order of MAX**2
32    iterations.  The size of an octet may seem appropriate for MAX and
33    makes an upper limit for simple testing.  For the CRIS simulator,
34    making this 256 added 90s to the test-run (2GHz P4) while 64 (4s) was
35    enough to spot the bugs that had crept in, hence the number chosen.  */
36 #define MAX 64
37 
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41 
42 #define TOO_MANY_ERRORS 11
43 int errors = 0;
44 
45 #define DEBUGP					\
46  if (errors == TOO_MANY_ERRORS)			\
47    printf ("Further errors omitted\n");		\
48  else if (errors < TOO_MANY_ERRORS)		\
49    printf
50 
51 /* A safe target-independent memmove.  */
52 
53 void
mymemmove(unsigned char * dest,unsigned char * src,size_t n)54 mymemmove (unsigned char *dest, unsigned char *src, size_t n)
55 {
56   if ((src <= dest && src + n <= dest)
57       || src >= dest)
58     while (n-- > 0)
59       *dest++ = *src++;
60   else
61     {
62       dest += n;
63       src += n;
64       while (n-- > 0)
65 	*--dest = *--src;
66     }
67 }
68 
69 /* It's either the noinline attribute or forcing the test framework to
70    pass -fno-builtin-memmove.  */
71 void
72 xmemmove (unsigned char *dest, unsigned char *src, size_t n)
73      __attribute__ ((__noinline__));
74 
75 void
xmemmove(unsigned char * dest,unsigned char * src,size_t n)76 xmemmove (unsigned char *dest, unsigned char *src, size_t n)
77 {
78   void *retp;
79   retp = memmove (dest, src, n);
80 
81   if (retp != dest)
82     {
83       errors++;
84       DEBUGP ("memmove of n bytes returned %p instead of dest=%p\n",
85 	      retp, dest);
86     }
87 }
88 
89 
90 /* Fill the array with something we can associate with a position, but
91    not exactly the same as the position index.  */
92 
93 void
fill(unsigned char dest[MAX * 3])94 fill (unsigned char dest[MAX*3])
95 {
96   size_t i;
97   for (i = 0; i < MAX*3; i++)
98     dest[i] = (10 + i) % MAX;
99 }
100 
101 int
main(void)102 main (void)
103 {
104   size_t i;
105   int errors = 0;
106 
107   /* Leave some room before and after the area tested, so we can detect
108      overwrites of up to N bytes, N being the amount tested.  If you
109      want to test using valgrind, make these malloced instead.  */
110   unsigned char from_test[MAX*3];
111   unsigned char to_test[MAX*3];
112   unsigned char from_known[MAX*3];
113   unsigned char to_known[MAX*3];
114 
115   /* Non-overlap.  */
116   for (i = 0; i < MAX; i++)
117     {
118       /* Do the memmove first before setting the known array, so we know
119          it didn't change any of the known array.  */
120       fill (from_test);
121       fill (to_test);
122       xmemmove (to_test + MAX, 1 + from_test + MAX, i);
123 
124       fill (from_known);
125       fill (to_known);
126       mymemmove (to_known + MAX, 1 + from_known + MAX, i);
127 
128       if (memcmp (to_known, to_test, sizeof (to_known)) != 0)
129 	{
130 	  errors++;
131 	  DEBUGP ("memmove failed non-overlap test for %lu bytes\n", (unsigned long) i);
132 	}
133     }
134 
135   /* Overlap-from-before.  */
136   for (i = 0; i < MAX; i++)
137     {
138       size_t j;
139       for (j = 0; j < i; j++)
140 	{
141 	  fill (to_test);
142 	  xmemmove (to_test + MAX * 2 - i, to_test + MAX * 2 - i - j, i);
143 
144 	  fill (to_known);
145 	  mymemmove (to_known + MAX * 2 - i, to_known + MAX * 2 - i - j, i);
146 
147 	  if (memcmp (to_known, to_test, sizeof (to_known)) != 0)
148 	    {
149 	      errors++;
150 	      DEBUGP ("memmove failed for %lu bytes,"
151 		      " with src %lu bytes before dest\n",
152 		      (unsigned long) i, (unsigned long) j);
153 	    }
154 	}
155     }
156 
157   /* Overlap-from-after.  */
158   for (i = 0; i < MAX; i++)
159     {
160       size_t j;
161       for (j = 0; j < i; j++)
162 	{
163 	  fill (to_test);
164 	  xmemmove (to_test + MAX, to_test + MAX + j, i);
165 
166 	  fill (to_known);
167 	  mymemmove (to_known + MAX, to_known + MAX + j, i);
168 
169 	  if (memcmp (to_known, to_test, sizeof (to_known)) != 0)
170 	    {
171 	      errors++;
172 	      DEBUGP ("memmove failed when moving %lu bytes,"
173 		      " with src %lu bytes after dest\n",
174 		      (unsigned long) i, (unsigned long) j);
175 	    }
176 	}
177     }
178 
179   if (errors != 0)
180     abort ();
181   exit (0);
182 }
183