Use a superior strcasestr

This commit is contained in:
James R 2019-04-21 23:18:40 -07:00
parent 70df5242a3
commit 7bf819f5af
3 changed files with 113 additions and 67 deletions

View File

@ -1672,73 +1672,6 @@ void strcatbf(char *s1, const char *s2, const char *s3)
strcat(s1, tmp);
}
/** Locate a substring, case-insensitively.
* Know that I hate this style. -James
*
* \param s The string to search within.
* \param q The substring to find.
* \return a pointer to the located substring, or NULL if it could be found.
*/
char *strcasestr(const char *s, const char *q)
{
void **vpp;/* a hack! */
size_t qz;
const char *up;
const char *lp;
int uc;
int lc;
qz = strlen(q);
uc = toupper(*q);
lc = tolower(*q);
up = s;
lp = s;
do
{
if (uc > 0)
{
up = strchr(up, uc);
if (!up || ( lc == 0 && lp < up ))
uc = -1;
else
if (strnicmp(q, up, qz) == 0)
uc = 0;
else
up++;
}
if (lc > 0)
{
lp = strchr(lp, lc);
if (!lp || ( uc == 0 && up < lp ))
lc = -1;
else
if (strnicmp(q, lp, qz) == 0)
lc = 0;
else
lp++;
}
}
while (( uc > 0 ) || ( lc > 0 )) ;
if (uc == 0)
vpp = (void **)&up;
else
vpp = (void **)&lp;
/*
We can dereference a double void pointer and cast it to remove const.
This works because the original variable (the pointer) is writeable,
but its value is not.
*/
return (char *)*vpp;
}
/** Converts an ASCII Hex string into an integer. Thanks, Borland!
* <Inuyasha> I don't know if this belongs here specifically, but it sure
* doesn't belong in p_spec.c, that's for sure

110
src/strcasestr.c Normal file
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@ -0,0 +1,110 @@
/*
strcasestr -- case insensitive substring searching function.
*/
/*
Copyright 2019 James R.
All rights reserved.
Redistribution and use in source forms, with or without modification, is
permitted provided that the following condition is met:
1. Redistributions of source code must retain the above copyright notice, this
condition and the following disclaimer.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#define SWAP( a, b ) \
(\
(a) ^= (b),\
(b) ^= (a),\
(a) ^= (b)\
)
static inline int
trycmp (char **pp, char *cp,
const char *q, size_t qn)
{
char *p;
p = (*pp);
if (strncasecmp(p, q, qn) == 0)
return 0;
(*pp) = strchr(&p[1], (*cp));
return 1;
}
static inline void
swapp (char ***ppap, char ***ppbp, char **cpap, char **cpbp)
{
SWAP(*(intptr_t *)ppap, *(intptr_t *)ppbp);
SWAP(*(intptr_t *)cpap, *(intptr_t *)cpbp);
}
char *
strcasestr (const char *s, const char *q)
{
size_t qn;
char uc;
char lc;
char *up;
char *lp;
char **ppa;
char **ppb;
char *cpa;
char *cpb;
uc = toupper(*q);
lc = tolower(*q);
up = strchr(s, uc);
lp = strchr(s, lc);
if (!( (intptr_t)up|(intptr_t)lp ))
return 0;
if (!lp || up < lp)
{
ppa = &up;
ppb = &lp;
cpa = &uc;
cpb = &lc;
}
else
{
ppa = &lp;
ppb = &up;
cpa = &lc;
cpb = &uc;
}
qn = strlen(q);
for (;;)
{
if (trycmp(ppa, cpa, q, qn) == 0)
return (*ppa);
if (!( (intptr_t)up|(intptr_t)lp ))
break;
if (!(*ppa) || ( (*ppb) && (*ppb) < (*ppa) ))
swapp(&ppa, &ppb, &cpa, &cpb);
}
return 0;
}

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@ -2,6 +2,7 @@
//-----------------------------------------------------------------------------
// Copyright (C) 2006 by Graue.
// Copyright (C) 2006-2018 by Sonic Team Junior.
// Copyright (C) 2019 by James R.
//
// This program is free software distributed under the
// terms of the GNU General Public License, version 2.
@ -50,3 +51,5 @@ size_t strlcpy(char *dst, const char *src, size_t siz)
}
#endif
#include "strcasestr.c"