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/* IBM_PROLOG_BEGIN_TAG */
/* This is an automatically generated prolog. */
/* */
/* $Source: src/lib/string.C $ */
/* */
/* IBM CONFIDENTIAL */
/* */
/* COPYRIGHT International Business Machines Corp. 2011,2013 */
/* */
/* p1 */
/* */
/* Object Code Only (OCO) source materials */
/* Licensed Internal Code Source Materials */
/* IBM HostBoot Licensed Internal Code */
/* */
/* The source code for this program is not published or otherwise */
/* divested of its trade secrets, irrespective of what has been */
/* deposited with the U.S. Copyright Office. */
/* */
/* Origin: 30 */
/* */
/* IBM_PROLOG_END_TAG */
#include <string.h>
extern "C" void *memset(void *vdest, int ch, size_t len)
{
// TODO: align to an 8-byte boundary
// Loop, storing 8 bytes every 3 instructions
long *ldest = reinterpret_cast<long *>(vdest);
if (len >= sizeof(long))
{
long lch = ch & 0xFF;
lch |= lch<<8;
lch |= lch<<16;
lch |= lch<<32;
size_t len8 = len / sizeof(long);
size_t i = len8;
do
{
ldest[--i] = lch;
}
while( i > 0 );
ldest += len8;
len -= len8 * sizeof(long);
}
// Loop, storing 1 byte every 3 instructions
char *cdest = reinterpret_cast<char *>(ldest);
while (len >= sizeof(char))
{
*cdest++ = ch;
len -= sizeof(char);
}
return vdest;
}
extern "C" void bzero(void *vdest, size_t len)
{
memset(vdest, 0, len);
}
extern "C" void *memcpy(void *vdest, const void *vsrc, size_t len)
{
// TODO: align to an 8-byte boundary?
// Loop, copying 8 bytes every 5 instructions (TODO: 8/4 should be possible)
long *ldest = reinterpret_cast<long *>(vdest);
const long *lsrc = reinterpret_cast<const long *>(vsrc);
while (len >= sizeof(long))
{
*ldest++ = *lsrc++;
len -= sizeof(long);
}
// Loop, copying 1 byte every 4 instructions
char *cdest = reinterpret_cast<char *>(ldest);
const char *csrc = reinterpret_cast<const char *>(lsrc);
for (size_t i = 0; i < len; ++i)
{
cdest[i] = csrc[i];
}
return vdest;
}
extern "C" void *memmove(void *vdest, const void *vsrc, size_t len)
{
// Copy first-to-last
if (vdest <= vsrc)
{
return memcpy(vdest,vsrc,len);
}
// Copy last-to-first (TO_DO: optimize)
char *dest = reinterpret_cast<char *>(vdest);
const char *src = reinterpret_cast<const char *>(vsrc);
for (size_t i = len; i > 0;)
{
--i;
dest[i] = src[i];
}
return vdest;
}
extern "C" int memcmp(const void *p1, const void *p2, size_t len)
{
const char *c1 = reinterpret_cast<const char *>(p1);
const char *c2 = reinterpret_cast<const char *>(p2);
for (size_t i = 0; i < len; ++i)
{
long n = static_cast<long>(c1[i]) - static_cast<long>(c2[i]);
if (n != 0)
{
return n;
}
}
return 0;
}
extern "C" void *memmem(const void *haystack, size_t haystacklen,
const void *needle, size_t needlelen)
{
const void * result = NULL;
if (haystacklen >= needlelen)
{
const char * c_haystack = static_cast<const char *>(haystack);
const char * c_needle = static_cast<const char *>(needle);
bool match = false;
for (size_t i = 0; i <= (haystacklen - needlelen); i++)
{
match = true;
for (size_t j = 0; j < needlelen; j++)
{
if (*(c_haystack + i + j) != *(c_needle + j))
{
match = false;
break;
}
}
if (match)
{
result = (c_haystack + i);
break;
}
}
}
return const_cast<void *>(result);
}
extern "C" char* strcpy(char* d, const char* s)
{
char* d1 = d;
do
{
*d1 = *s;
if (*s == '\0') return d;
d1++; s++;
} while(1);
}
extern "C" int strcmp(const char* a, const char* b)
{
while((*a != '\0') && (*b != '\0'))
{
if (*a == *b)
{
a++; b++;
}
else
{
return (*a > *b) ? 1 : -1;
}
}
if (*a == *b)
return 0;
if (*a == '\0')
return -1;
else
return 1;
}
extern "C" size_t strlen(const char* a)
{
size_t length = 0;
while(*a++)
{
length++;
}
return length;
}
extern "C" size_t strnlen(const char* s, size_t n)
{
size_t length = 0;
while((length < n) && (*s++))
{
length++;
}
return length;
}
extern "C" char* strcat(char* d, const char* s)
{
char* _d = d;
while(*_d)
{
_d++;
}
while(*s)
{
*_d = *s;
_d++; s++;
}
*_d = '\0';
return d;
}
extern "C" char* strncat(char* d, const char* s, size_t n)
{
char* _d = d;
while(*_d)
{
_d++;
}
while((*s) && (0 != n))
{
*_d = *s;
_d++; s++;
n--;
}
*_d = '\0';
return d;
}
extern "C" char* strchr(const char* s, int c)
{
while((*s != '\0') && (*s != c))
{
s++;
}
if (*s == c) return (char*)s;
return NULL;
}
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