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/* Copyright (C) 2004, 2005 Free Software Foundation.
Ensure builtin __strncpy_chk performs correctly. */
extern void abort (void);
typedef __SIZE_TYPE__ size_t;
extern size_t strlen(const char *);
extern void *memcpy (void *, const void *, size_t);
extern char *strncpy (char *, const char *, size_t);
extern int memcmp (const void *, const void *, size_t);
extern int strcmp (const char *, const char *);
extern int strncmp (const char *, const char *, size_t);
extern void *memset (void *, int, size_t);
#include "chk.h"
const char s1[] = "123";
char p[32] = "";
char * volatile s2 = "defg"; /* prevent constant propagation to happen when whole program assumptions are made. */
char * volatile s3 = "FGH"; /* prevent constant propagation to happen when whole program assumptions are made. */
char *s4;
volatile size_t l1 = 1; /* prevent constant propagation to happen when whole program assumptions are made. */
int i;
void
__attribute__((noinline))
test1 (void)
{
const char *const src = "hello world";
const char *src2;
char dst[64], *dst2;
strncpy_disallowed = 1;
chk_calls = 0;
memset (dst, 0, sizeof (dst));
if (strncpy (dst, src, 4) != dst || strncmp (dst, src, 4))
abort();
memset (dst, 0, sizeof (dst));
if (strncpy (dst+16, src, 4) != dst+16 || strncmp (dst+16, src, 4))
abort();
memset (dst, 0, sizeof (dst));
if (strncpy (dst+32, src+5, 4) != dst+32 || strncmp (dst+32, src+5, 4))
abort();
memset (dst, 0, sizeof (dst));
dst2 = dst;
if (strncpy (++dst2, src+5, 4) != dst+1 || strncmp (dst2, src+5, 4)
|| dst2 != dst+1)
abort();
memset (dst, 0, sizeof (dst));
if (strncpy (dst, src, 0) != dst || strcmp (dst, ""))
abort();
memset (dst, 0, sizeof (dst));
dst2 = dst; src2 = src;
if (strncpy (++dst2, ++src2, 0) != dst+1 || strcmp (dst2, "")
|| dst2 != dst+1 || src2 != src+1)
abort();
memset (dst, 0, sizeof (dst));
dst2 = dst; src2 = src;
if (strncpy (++dst2+5, ++src2+5, 0) != dst+6 || strcmp (dst2+5, "")
|| dst2 != dst+1 || src2 != src+1)
abort();
memset (dst, 0, sizeof (dst));
if (strncpy (dst, src, 12) != dst || strcmp (dst, src))
abort();
/* Test at least one instance of the __builtin_ style. We do this
to ensure that it works and that the prototype is correct. */
memset (dst, 0, sizeof (dst));
if (__builtin_strncpy (dst, src, 4) != dst || strncmp (dst, src, 4))
abort();
memset (dst, 0, sizeof (dst));
if (strncpy (dst, i++ ? "xfoo" + 1 : "bar", 4) != dst
|| strcmp (dst, "bar")
|| i != 1)
abort ();
if (chk_calls)
abort ();
strncpy_disallowed = 0;
}
void
__attribute__((noinline))
test2 (void)
{
chk_calls = 0;
/* No runtime checking should be done here, both destination
and length are unknown. */
strncpy (s4, "abcd", l1 + 1);
if (chk_calls)
abort ();
}
/* Test whether compile time checking is done where it should
and so is runtime object size checking. */
void
__attribute__((noinline))
test3 (void)
{
struct A { char buf1[10]; char buf2[10]; } a;
char *r = l1 == 1 ? &a.buf1[5] : &a.buf2[4];
char buf3[20];
int i;
const char *l;
size_t l2;
/* The following calls should do runtime checking
- source length is not known, but destination is. */
chk_calls = 0;
strncpy (a.buf1 + 2, s3 + 3, l1);
strncpy (r, s3 + 2, l1 + 2);
r = l1 == 1 ? __builtin_alloca (4) : &a.buf2[7];
strncpy (r, s2 + 2, l1 + 2);
strncpy (r + 2, s3 + 3, l1);
r = buf3;
for (i = 0; i < 4; ++i)
{
if (i == l1 - 1)
r = &a.buf1[1];
else if (i == l1)
r = &a.buf2[7];
else if (i == l1 + 1)
r = &buf3[5];
else if (i == l1 + 2)
r = &a.buf1[9];
}
strncpy (r, s2 + 4, l1);
if (chk_calls != 5)
abort ();
/* Following have known destination and known length,
so if optimizing certainly shouldn't result in the checking
variants. */
chk_calls = 0;
strncpy (a.buf1 + 2, "", 3);
strncpy (a.buf1 + 2, "", 0);
strncpy (r, "a", 1);
strncpy (r, "a", 3);
r = l1 == 1 ? __builtin_alloca (4) : &a.buf2[7];
strncpy (r, s1 + 1, 3);
strncpy (r, s1 + 1, 2);
r = buf3;
l = "abc";
l2 = 4;
for (i = 0; i < 4; ++i)
{
if (i == l1 - 1)
r = &a.buf1[1], l = "e", l2 = 2;
else if (i == l1)
r = &a.buf2[7], l = "gh", l2 = 3;
else if (i == l1 + 1)
r = &buf3[5], l = "jkl", l2 = 4;
else if (i == l1 + 2)
r = &a.buf1[9], l = "", l2 = 1;
}
strncpy (r, "", 1);
/* Here, strlen (l) + 1 is known to be at most 4 and
__builtin_object_size (&buf3[16], 0) is 4, so this doesn't need
runtime checking. */
strncpy (&buf3[16], l, l2);
strncpy (&buf3[15], "abc", l2);
strncpy (&buf3[10], "fghij", l2);
if (chk_calls)
abort ();
chk_calls = 0;
}
/* Test whether runtime and/or compile time checking catches
buffer overflows. */
void
__attribute__((noinline))
test4 (void)
{
struct A { char buf1[10]; char buf2[10]; } a;
char buf3[20];
chk_fail_allowed = 1;
/* Runtime checks. */
if (__builtin_setjmp (chk_fail_buf) == 0)
{
strncpy (&a.buf2[9], s2 + 4, l1 + 1);
abort ();
}
if (__builtin_setjmp (chk_fail_buf) == 0)
{
strncpy (&a.buf2[7], s3, l1 + 4);
abort ();
}
/* This should be detectable at compile time already. */
if (__builtin_setjmp (chk_fail_buf) == 0)
{
strncpy (&buf3[19], "abc", 2);
abort ();
}
if (__builtin_setjmp (chk_fail_buf) == 0)
{
strncpy (&buf3[18], "", 3);
abort ();
}
chk_fail_allowed = 0;
}
void
main_test (void)
{
#ifndef __OPTIMIZE__
/* Object size checking is only intended for -O[s123]. */
return;
#endif
__asm ("" : "=r" (s2) : "0" (s2));
__asm ("" : "=r" (s3) : "0" (s3));
__asm ("" : "=r" (l1) : "0" (l1));
test1 ();
s4 = p;
test2 ();
test3 ();
test4 ();
}
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