| |
| /*--------------------------------------------------------------------*/ |
| /*--- 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) 2000-2005 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 "memcheck.h" |
| #include "valgrind.h" |
| |
| /* --------------------------------------------------------------------- |
| We have our own versions of these functions for two reasons: |
| (a) it allows us to do overlap checking |
| (b) some of the normal versions are hyper-optimised, which fools |
| Memcheck and cause spurious value warnings. Our versions are |
| simpler. |
| |
| THEY RUN ON THE 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, SizeT dstlen, SizeT 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; |
| } |
| } |
| |
| // This is a macro rather than a function because we don't want to have an |
| // extra function in the stack trace. |
| #define RECORD_OVERLAP_ERROR(s, p_extra) \ |
| { \ |
| Word unused_res; \ |
| VALGRIND_MAGIC_SEQUENCE(unused_res, 0, \ |
| _VG_USERREQ__MEMCHECK_RECORD_OVERLAP_ERROR, \ |
| s, p_extra, 0, 0); \ |
| } |
| |
| static __inline__ |
| void complain2 ( Char* s, char* dst, const char* src ) |
| { |
| OverlapExtra extra = { |
| .src = (Addr)src, .dst = (Addr)dst, .len = -1, |
| }; |
| 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, |
| }; |
| RECORD_OVERLAP_ERROR( s, &extra ); |
| } |
| |
| // GCC complains if we have a non-static function without a previous |
| // declaration. We don't really need such declarations for these functions |
| // because we're overriding standard system functions, but this macro puts |
| // them in anyway just to shut GCC up. |
| #define DECL(a) a; a |
| |
| DECL( 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++; |
| } |
| } |
| |
| DECL( 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++; |
| } |
| } |
| |
| DECL( 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; |
| } |
| |
| DECL( char* strncat ( char* dst, const char* src, SizeT n ) ) |
| { |
| const Char* src_orig = src; |
| Char* dst_orig = dst; |
| SizeT 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; |
| } |
| |
| DECL( SizeT strnlen ( const char* str, SizeT n ) ) |
| { |
| SizeT i = 0; |
| while (i < n && str[i] != 0) i++; |
| return i; |
| } |
| |
| DECL( SizeT strlen ( const char* str ) ) |
| { |
| SizeT i = 0; |
| while (str[i] != 0) i++; |
| return i; |
| } |
| |
| DECL( 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; |
| } |
| |
| DECL( char* strncpy ( char* dst, const char* src, SizeT n ) ) |
| { |
| const Char* src_orig = src; |
| Char* dst_orig = dst; |
| SizeT 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; |
| } |
| |
| DECL( int strncmp ( const char* s1, const char* s2, SizeT nmax ) ) |
| { |
| SizeT 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++; |
| } |
| } |
| |
| DECL( 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; |
| } |
| |
| DECL( void* memchr(const void *s, int c, SizeT n) ) |
| { |
| SizeT 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; |
| } |
| |
| DECL( void* memcpy( void *dst, const void *src, SizeT len ) ) |
| { |
| register char *d; |
| register char *s; |
| |
| if (len == 0) |
| return dst; |
| |
| 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; |
| } |
| |
| DECL( int memcmp ( const void *s1V, const void *s2V, SizeT 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; |
| } |
| |
| |
| /* Copy SRC to DEST, returning the address of the terminating '\0' in |
| DEST. (minor variant of strcpy) */ |
| |
| DECL( char* stpcpy ( 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("stpcpy", dst_orig, src_orig); |
| |
| return dst; |
| } |
| |
| DECL( void *memset(void *s, Int c, SizeT n) ) |
| { |
| unsigned char *cp = s; |
| |
| while(n--) |
| *cp++ = c; |
| |
| return s; |
| } |
| |
| DECL( void *memmove(void *dstV, const void *srcV, SizeT n) ) |
| { |
| SizeT i; |
| Char* dst = (Char*)dstV; |
| Char* src = (Char*)srcV; |
| if (dst < src) { |
| for (i = 0; i < n; i++) |
| dst[i] = src[i]; |
| } |
| else |
| if (dst > src) { |
| for (i = 0; i < n; i++) |
| dst[n-i-1] = src[n-i-1]; |
| } |
| return dst; |
| } |
| |
| |
| /* Find the first occurrence of C in S or the final NUL byte. */ |
| |
| DECL( char* glibc232_strchrnul (const char* s, int c_in) ) |
| { |
| unsigned char c = (unsigned char) c_in; |
| unsigned char* char_ptr = (unsigned char *)s; |
| while (1) { |
| if (*char_ptr == 0) return char_ptr; |
| if (*char_ptr == c) return char_ptr; |
| char_ptr++; |
| } |
| } |
| |
| |
| /* Find the first occurrence of C in S. */ |
| |
| DECL( char* glibc232_rawmemchr (const char* s, int c_in) ) |
| { |
| unsigned char c = (unsigned char) c_in; |
| unsigned char* char_ptr = (unsigned char *)s; |
| while (1) { |
| if (*char_ptr == c) return char_ptr; |
| char_ptr++; |
| } |
| } |
| |
| |
| /*--------------------------------------------------------------------*/ |
| /*--- end ---*/ |
| /*--------------------------------------------------------------------*/ |