memcheck/mac_replace_strmem.c - platform/external/valgrind - Gitiles


 /*--------------------------------------------------------------------*/
 /*--- Replacements for strcpy(), memcpy() et al, which run on the  ---*/
 /*--- simulated CPU.                                               ---*/
 /*---                                         mac_replace_strmem.c ---*/
 /*--------------------------------------------------------------------*/

 /*
    This file is part of MemCheck, a heavyweight Valgrind tool for
    detecting memory errors.

    Copyright (C) 2000-2003 Julian Seward
       jseward@acm.org

    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
    published by the Free Software Foundation; either version 2 of the
    License, or (at your option) any later version.

    This program is distributed in the hope that it will be useful, but
    WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
    02111-1307, USA.

    The GNU General Public License is contained in the file COPYING.
 */

 #include "mc_include.h"
 #include "valgrind.h"

 /* ---------------------------------------------------------------------
    The normal versions of these functions are hyper-optimised, which fools
    Memcheck and cause spurious value warnings.  So we replace them with
    simpler versions.  THEY RUN ON SIMD CPU!
    ------------------------------------------------------------------ */

 /* Figure out if [dst .. dst+dstlen-1] overlaps with
                  [src .. src+srclen-1].
    We assume that the address ranges do not wrap around
    (which is safe since on Linux addresses >= 0xC0000000
    are not accessible and the program will segfault in this
    circumstance, presumably).
 */
 static __inline__
 Bool is_overlap ( void* dst, const void* src, UInt dstlen, UInt srclen )
 {
    Addr loS, hiS, loD, hiD;

    if (dstlen == 0 || srclen == 0)
       return False;

    loS = (Addr)src;
    loD = (Addr)dst;
    hiS = loS + srclen - 1;
    hiD = loD + dstlen - 1;

    /* So figure out if [loS .. hiS] overlaps with [loD .. hiD]. */
    if (loS < loD) {
       return !(hiS < loD);
    }
    else if (loD < loS) {
       return !(hiD < loS);
    }
    else {
       /* They start at same place.  Since we know neither of them has
          zero length, they must overlap. */
       return True;
    }
 }


 static __inline__
 void complain2 ( Char* s, char* dst, const char* src )
 {
    OverlapExtra extra = {
       .src = (Addr)src, .dst = (Addr)dst, .len = -1,
    };
    VALGRIND_NON_SIMD_CALL2( MAC_(record_overlap_error), s, &extra );
 }

 static __inline__
 void complain3 ( Char* s, void* dst, const void* src, int n )
 {
    /* Must wrap it up here, because we cannot pass 4 args to core */
    OverlapExtra extra = {
       .src = (Addr)src, .dst = (Addr)dst, .len = n,
    };
    VALGRIND_NON_SIMD_CALL2( MAC_(record_overlap_error), s, &extra );
 }

 char* strrchr ( const char* s, int c )
 {
    UChar  ch   = (UChar)((UInt)c);
    UChar* p    = (UChar*)s;
    UChar* last = NULL;
    while (True) {
       if (*p == ch) last = p;
       if (*p == 0) return last;
       p++;
    }
 }

 char* strchr ( const char* s, int c )
 {
    UChar  ch = (UChar)((UInt)c);
    UChar* p  = (UChar*)s;
    while (True) {
       if (*p == ch) return p;
       if (*p == 0) return NULL;
       p++;
    }
 }

 char* strcat ( char* dst, const char* src )
 {
    const Char* src_orig = src;
          Char* dst_orig = dst;
    while (*dst) dst++;
    while (*src) *dst++ = *src++;
    *dst = 0;

    /* This is a bit redundant, I think;  any overlap and the strcat will
       go forever... or until a seg fault occurs. */
    if (is_overlap(dst_orig,
                   src_orig,
                   (Addr)dst-(Addr)dst_orig+1,
                   (Addr)src-(Addr)src_orig+1))
       complain2("strcat", dst_orig, src_orig);

    return dst_orig;
 }

 char* strncat ( char* dst, const char* src, int n )
 {
    const Char* src_orig = src;
          Char* dst_orig = dst;
    Int   m = 0;

    while (*dst) dst++;
    while (m   < n && *src) { m++; *dst++ = *src++; } /* concat <= n chars */
    *dst = 0;                                         /* always add null   */

    /* This checks for overlap after copying, unavoidable without
       pre-counting lengths... should be ok */
    if (is_overlap(dst_orig,
                   src_orig,
                   (Addr)dst-(Addr)dst_orig+1,
                   (Addr)src-(Addr)src_orig+1))
       complain3("strncat", dst_orig, src_orig, n);

    return dst_orig;
 }

 unsigned int strlen ( const char* str )
 {
    UInt i = 0;
    while (str[i] != 0) i++;
    return i;
 }

 char* strcpy ( char* dst, const char* src )
 {
    const Char* src_orig = src;
          Char* dst_orig = dst;

    while (*src) *dst++ = *src++;
    *dst = 0;

    /* This checks for overlap after copying, unavoidable without
       pre-counting length... should be ok */
    if (is_overlap(dst_orig,
                   src_orig,
                   (Addr)dst-(Addr)dst_orig+1,
                   (Addr)src-(Addr)src_orig+1))
       complain2("strcpy", dst_orig, src_orig);

    return dst_orig;
 }

 char* strncpy ( char* dst, const char* src, int n )
 {
    const Char* src_orig = src;
          Char* dst_orig = dst;
    Int   m = 0;

    while (m   < n && *src) { m++; *dst++ = *src++; }
    /* Check for overlap after copying; all n bytes of dst are relevant,
       but only m+1 bytes of src if terminator was found */
    if (is_overlap(dst_orig, src_orig, n, (m < n) ? m+1 : n))
       complain3("strncpy", dst, src, n);
    while (m++ < n) *dst++ = 0;         /* must pad remainder with nulls */

    return dst_orig;
 }

 int strncmp ( const unsigned char* s1, const unsigned char* s2,
               unsigned int nmax )
 {
    unsigned int n = 0;
    while (True) {
       if (n >= nmax) return 0;
       if (*s1 == 0 && *s2 == 0) return 0;
       if (*s1 == 0) return -1;
       if (*s2 == 0) return 1;

       if (*(unsigned char*)s1 < *(unsigned char*)s2) return -1;
       if (*(unsigned char*)s1 > *(unsigned char*)s2) return 1;

       s1++; s2++; n++;
    }
 }

 int strcmp ( const char* s1, const char* s2 )
 {
    register unsigned char c1;
    register unsigned char c2;
    while (True) {
       c1 = *(unsigned char *)s1;
       c2 = *(unsigned char *)s2;
       if (c1 != c2) break;
       if (c1 == 0) break;
       s1++; s2++;
    }
    if ((unsigned char)c1 < (unsigned char)c2) return -1;
    if ((unsigned char)c1 > (unsigned char)c2) return 1;
    return 0;
 }

 void* memchr(const void *s, int c, unsigned int n)
 {
    unsigned int i;
    UChar c0 = (UChar)c;
    UChar* p = (UChar*)s;
    for (i = 0; i < n; i++)
       if (p[i] == c0) return (void*)(&p[i]);
    return NULL;
 }

 void* memcpy( void *dst, const void *src, unsigned int len )
 {
    register char *d;
    register char *s;

    if (is_overlap(dst, src, len, len))
       complain3("memcpy", dst, src, len);

    if ( dst > src ) {
       d = (char *)dst + len - 1;
       s = (char *)src + len - 1;
       while ( len >= 4 ) {
          *d-- = *s--;
          *d-- = *s--;
          *d-- = *s--;
          *d-- = *s--;
          len -= 4;
       }
       while ( len-- ) {
          *d-- = *s--;
       }
    } else if ( dst < src ) {
       d = (char *)dst;
       s = (char *)src;
       while ( len >= 4 ) {
          *d++ = *s++;
          *d++ = *s++;
          *d++ = *s++;
          *d++ = *s++;
          len -= 4;
       }
       while ( len-- ) {
          *d++ = *s++;
       }
    }
    return dst;
 }

 int memcmp ( const void *s1V, const void *s2V, unsigned int n )
 {
    int res;
    unsigned char a0;
    unsigned char b0;
    unsigned char* s1 = (unsigned char*)s1V;
    unsigned char* s2 = (unsigned char*)s2V;

    while (n != 0) {
       a0 = s1[0];
       b0 = s2[0];
       s1 += 1;
       s2 += 1;
       res = ((int)a0) - ((int)b0);
       if (res != 0)
          return res;
       n -= 1;
    }
    return 0;
 }

 /*--------------------------------------------------------------------*/
 /*--- end                                     mac_replace_strmem.c ---*/
 /*--------------------------------------------------------------------*/

	/--------------------------------------------------------------------/
	/--- Replacements for strcpy(), memcpy() et al, which run on the ---/
	/--- simulated CPU. ---/
	/--- mac_replace_strmem.c ---/
	/--------------------------------------------------------------------/

	/*
	This file is part of MemCheck, a heavyweight Valgrind tool for
	detecting memory errors.

	Copyright (C) 2000-2003 Julian Seward
	jseward@acm.org

	This program is free software; you can redistribute it and/or
	modify it under the terms of the GNU General Public License as
	published by the Free Software Foundation; either version 2 of the
	License, or (at your option) any later version.

	This program is distributed in the hope that it will be useful, but
	WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program; if not, write to the Free Software
	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
	02111-1307, USA.

	The GNU General Public License is contained in the file COPYING.
	*/

	#include "mc_include.h"
	#include "valgrind.h"

	/* ---------------------------------------------------------------------
	The normal versions of these functions are hyper-optimised, which fools
	Memcheck and cause spurious value warnings. So we replace them with
	simpler versions. THEY RUN ON SIMD CPU!
	------------------------------------------------------------------ */

	/* Figure out if [dst .. dst+dstlen-1] overlaps with
	[src .. src+srclen-1].
	We assume that the address ranges do not wrap around
	(which is safe since on Linux addresses >= 0xC0000000
	are not accessible and the program will segfault in this
	circumstance, presumably).
	*/
	static __inline__
	Bool is_overlap ( void* dst, const void* src, UInt dstlen, UInt srclen )
	{
	Addr loS, hiS, loD, hiD;

	if (dstlen == 0 \|\| srclen == 0)
	return False;

	loS = (Addr)src;
	loD = (Addr)dst;
	hiS = loS + srclen - 1;
	hiD = loD + dstlen - 1;

	/* So figure out if [loS .. hiS] overlaps with [loD .. hiD]. */
	if (loS < loD) {
	return !(hiS < loD);
	}
	else if (loD < loS) {
	return !(hiD < loS);
	}
	else {
	/* They start at same place. Since we know neither of them has
	zero length, they must overlap. */
	return True;
	}
	}


	static __inline__
	void complain2 ( Char* s, char* dst, const char* src )
	{
	OverlapExtra extra = {
	.src = (Addr)src, .dst = (Addr)dst, .len = -1,
	};
	VALGRIND_NON_SIMD_CALL2( MAC_(record_overlap_error), s, &extra );
	}

	static __inline__
	void complain3 ( Char* s, void* dst, const void* src, int n )
	{
	/* Must wrap it up here, because we cannot pass 4 args to core */
	OverlapExtra extra = {
	.src = (Addr)src, .dst = (Addr)dst, .len = n,
	};
	VALGRIND_NON_SIMD_CALL2( MAC_(record_overlap_error), s, &extra );
	}

	char* strrchr ( const char* s, int c )
	{
	UChar ch = (UChar)((UInt)c);
	UChar* p = (UChar*)s;
	UChar* last = NULL;
	while (True) {
	if (*p == ch) last = p;
	if (*p == 0) return last;
	p++;
	}
	}

	char* strchr ( const char* s, int c )
	{
	UChar ch = (UChar)((UInt)c);
	UChar* p = (UChar*)s;
	while (True) {
	if (*p == ch) return p;
	if (*p == 0) return NULL;
	p++;
	}
	}

	char* strcat ( char* dst, const char* src )
	{
	const Char* src_orig = src;
	Char* dst_orig = dst;
	while (*dst) dst++;
	while (src) dst++ = *src++;
	*dst = 0;

	/* This is a bit redundant, I think; any overlap and the strcat will
	go forever... or until a seg fault occurs. */
	if (is_overlap(dst_orig,
	src_orig,
	(Addr)dst-(Addr)dst_orig+1,
	(Addr)src-(Addr)src_orig+1))
	complain2("strcat", dst_orig, src_orig);

	return dst_orig;
	}

	char* strncat ( char* dst, const char* src, int n )
	{
	const Char* src_orig = src;
	Char* dst_orig = dst;
	Int m = 0;

	while (*dst) dst++;
	while (m < n && src) { m++; dst++ = src++; } / concat <= n chars */
	dst = 0; / always add null */

	/* This checks for overlap after copying, unavoidable without
	pre-counting lengths... should be ok */
	if (is_overlap(dst_orig,
	src_orig,
	(Addr)dst-(Addr)dst_orig+1,
	(Addr)src-(Addr)src_orig+1))
	complain3("strncat", dst_orig, src_orig, n);

	return dst_orig;
	}

	unsigned int strlen ( const char* str )
	{
	UInt i = 0;
	while (str[i] != 0) i++;
	return i;
	}

	char* strcpy ( char* dst, const char* src )
	{
	const Char* src_orig = src;
	Char* dst_orig = dst;

	while (src) dst++ = *src++;
	*dst = 0;

	/* This checks for overlap after copying, unavoidable without
	pre-counting length... should be ok */
	if (is_overlap(dst_orig,
	src_orig,
	(Addr)dst-(Addr)dst_orig+1,
	(Addr)src-(Addr)src_orig+1))
	complain2("strcpy", dst_orig, src_orig);

	return dst_orig;
	}

	char* strncpy ( char* dst, const char* src, int n )
	{
	const Char* src_orig = src;
	Char* dst_orig = dst;
	Int m = 0;

	while (m < n && src) { m++; dst++ = *src++; }
	/* Check for overlap after copying; all n bytes of dst are relevant,
	but only m+1 bytes of src if terminator was found */
	if (is_overlap(dst_orig, src_orig, n, (m < n) ? m+1 : n))
	complain3("strncpy", dst, src, n);
	while (m++ < n) dst++ = 0; / must pad remainder with nulls */

	return dst_orig;
	}

	int strncmp ( const unsigned char* s1, const unsigned char* s2,
	unsigned int nmax )
	{
	unsigned int n = 0;
	while (True) {
	if (n >= nmax) return 0;
	if (s1 == 0 && s2 == 0) return 0;
	if (*s1 == 0) return -1;
	if (*s2 == 0) return 1;

	if ((unsigned char)s1 < (unsigned char)s2) return -1;
	if ((unsigned char)s1 > (unsigned char)s2) return 1;

	s1++; s2++; n++;
	}
	}

	int strcmp ( const char* s1, const char* s2 )
	{
	register unsigned char c1;
	register unsigned char c2;
	while (True) {
	c1 = (unsigned char )s1;
	c2 = (unsigned char )s2;
	if (c1 != c2) break;
	if (c1 == 0) break;
	s1++; s2++;
	}
	if ((unsigned char)c1 < (unsigned char)c2) return -1;
	if ((unsigned char)c1 > (unsigned char)c2) return 1;
	return 0;
	}

	void* memchr(const void *s, int c, unsigned int n)
	{
	unsigned int i;
	UChar c0 = (UChar)c;
	UChar* p = (UChar*)s;
	for (i = 0; i < n; i++)
	if (p[i] == c0) return (void*)(&p[i]);
	return NULL;
	}

	void* memcpy( void dst, const void src, unsigned int len )
	{
	register char *d;
	register char *s;

	if (is_overlap(dst, src, len, len))
	complain3("memcpy", dst, src, len);

	if ( dst > src ) {
	d = (char *)dst + len - 1;
	s = (char *)src + len - 1;
	while ( len >= 4 ) {
	d-- = s--;
	d-- = s--;
	d-- = s--;
	d-- = s--;
	len -= 4;
	}
	while ( len-- ) {
	d-- = s--;
	}
	} else if ( dst < src ) {
	d = (char *)dst;
	s = (char *)src;
	while ( len >= 4 ) {
	d++ = s++;
	d++ = s++;
	d++ = s++;
	d++ = s++;
	len -= 4;
	}
	while ( len-- ) {
	d++ = s++;
	}
	}
	return dst;
	}

	int memcmp ( const void s1V, const void s2V, unsigned int n )
	{
	int res;
	unsigned char a0;
	unsigned char b0;
	unsigned char* s1 = (unsigned char*)s1V;
	unsigned char* s2 = (unsigned char*)s2V;

	while (n != 0) {
	a0 = s1[0];
	b0 = s2[0];
	s1 += 1;
	s2 += 1;
	res = ((int)a0) - ((int)b0);
	if (res != 0)
	return res;
	n -= 1;
	}
	return 0;
	}

	/--------------------------------------------------------------------/
	/--- end mac_replace_strmem.c ---/
	/--------------------------------------------------------------------/