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Fix signedness in wcscmp comparison

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This commit is contained in:
Liubov Dmitrieva
2011-10-23 13:34:15 -04:00
committed by Ulrich Drepper
parent 774a2669af
commit 95584d3b33
5 changed files with 239 additions and 132 deletions
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89
string/test-strcmp.c
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@ -1,4 +1,4 @@
/* Test and measure STRCMP functions.
/* Test and measure strcmp and wcscmp functions.
Copyright (C) 1999, 2002, 2003, 2005, 2011 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Written by Jakub Jelinek <jakub@redhat.com>, 1999.
@ -23,7 +23,6 @@
#include "test-string.h"
#ifdef WIDE
# include <inttypes.h>
# include <wchar.h>
# define L(str) L##str
@ -34,12 +33,53 @@
# define SIMPLE_STRCMP simple_wcscmp
# define STUPID_STRCMP stupid_wcscmp
# define CHAR wchar_t
# define UCHAR uint32_t
# define UCHAR wchar_t
# define CHARBYTES 4
# define CHARBYTESLOG 2
# define CHARALIGN __alignof__ (CHAR)
# define MIDCHAR 0x7fffffff
# define LARGECHAR 0xfffffffe
# define CHAR__MAX WCHAR_MAX
# define CHAR__MIN WCHAR_MIN
/* Wcscmp uses signed semantics for comparison, not unsigned */
/* Avoid using substraction since possible overflow */
int
simple_wcscmp (const wchar_t *s1, const wchar_t *s2)
{
wchar_t c1, c2;
do
{
c1 = *s1++;
c2 = *s2++;
if (c2 == L'\0')
return c1 - c2;
}
while (c1 == c2);
return c1 < c2 ? -1 : 1;
}
int
stupid_wcscmp (const wchar_t *s1, const wchar_t *s2)
{
size_t ns1 = wcslen (s1) + 1;
size_t ns2 = wcslen (s2) + 1;
size_t n = ns1 < ns2 ? ns1 : ns2;
int ret = 0;
wchar_t c1, c2;
while (n--) {
c1 = *s1++;
c2 = *s2++;
if ((ret = c1 < c2 ? -1 : c1 == c2 ? 0 : 1) != 0)
break;
}
return ret;
}
#else
# define L(str) str
# define STRCMP strcmp
@ -55,31 +95,35 @@
# define CHARALIGN 1
# define MIDCHAR 0x7f
# define LARGECHAR 0xfe
#endif
typedef int (*proto_t) (const CHAR *, const CHAR *);
# define CHAR__MAX CHAR_MAX
# define CHAR__MIN CHAR_MIN
/* Strcmp uses unsigned semantics for comparison. */
int
SIMPLE_STRCMP (const CHAR *s1, const CHAR *s2)
simple_strcmp (const char *s1, const char *s2)
{
int ret;
while ((ret = *(UCHAR *) s1 - *(UCHAR *) s2++) == 0 && *s1++);
while ((ret = *(unsigned char *) s1 - *(unsigned char*) s2++) == 0 && *s1++);
return ret;
}
int
STUPID_STRCMP (const CHAR *s1, const CHAR *s2)
stupid_strcmp (const char *s1, const char *s2)
{
size_t ns1 = STRLEN (s1) + 1;
size_t ns2 = STRLEN (s2) + 1;
size_t ns1 = strlen (s1) + 1;
size_t ns2 = strlen (s2) + 1;
size_t n = ns1 < ns2 ? ns1 : ns2;
int ret = 0;
while (n--)
if ((ret = *(UCHAR *) s1++ - *(UCHAR *) s2++) != 0)
if ((ret = *(unsigned char *) s1++ - *(unsigned char *) s2++) != 0)
break;
return ret;
}
#endif
typedef int (*proto_t) (const CHAR *, const CHAR *);
IMPL (STUPID_STRCMP, 1)
IMPL (SIMPLE_STRCMP, 1)
@ -276,14 +320,31 @@ check (void)
STRCPY(s1, L("abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrs"));
STRCPY(s2, L("abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijkLMNOPQRSTUV"));
/* Check correct working for negatives values */
s1[0] = 1;
s2[0] = 1;
s1[1] = 1;
s2[1] = 1;
s1[2] = -1;
s2[2] = 3;
s1[3] = 0;
s2[3] = -1;
/* Check possible overflow bug, actual more for wcscmp */
s1[7] = CHAR__MIN;
s2[7] = CHAR__MAX;
size_t l1 = STRLEN (s1);
size_t l2 = STRLEN (s2);
for (size_t i1 = 0; i1 < l1; i1++)
for (size_t i2 = 0; i2 < l2; i2++)
{
int exp_result = SIMPLE_STRCMP (s1 + i1, s2 + i2);
FOR_EACH_IMPL (impl, 0)
check_result (impl, s1 + i1, s2 + i2, exp_result);
int exp_result = SIMPLE_STRCMP (s1 + i1, s2 + i2);
FOR_EACH_IMPL (impl, 0)
check_result (impl, s1 + i1, s2 + i2, exp_result);
}
}