236 lines
5.6 KiB
C++
236 lines
5.6 KiB
C++
|
|
#include "amxxmodule.h"
|
|
#include <string.h>
|
|
#include "utils.h"
|
|
|
|
int UTIL_CheckValidChar(char *c)
|
|
{
|
|
int count;
|
|
int bytecount = 0;
|
|
|
|
for (count = 1; (*c & 0xC0) == 0x80; count++)
|
|
{
|
|
c--;
|
|
}
|
|
|
|
switch (*c & 0xF0)
|
|
{
|
|
case 0xC0:
|
|
case 0xD0:
|
|
{
|
|
bytecount = 2;
|
|
break;
|
|
}
|
|
case 0xE0:
|
|
{
|
|
bytecount = 3;
|
|
break;
|
|
}
|
|
case 0xF0:
|
|
{
|
|
bytecount = 4;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (bytecount != count)
|
|
{
|
|
return count;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
unsigned int strncopy(char *dest, const char *src, size_t count)
|
|
{
|
|
if (!count)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
char *start = dest;
|
|
while ((*src) && (--count))
|
|
{
|
|
*dest++ = *src++;
|
|
}
|
|
*dest = '\0';
|
|
|
|
return (dest - start);
|
|
}
|
|
|
|
/**
|
|
* NOTE: Do not edit this for the love of god unless you have
|
|
* read the test cases and understand the code behind each one.
|
|
* While I don't guarantee there aren't mistakes, I do guarantee
|
|
* that plugins will end up relying on tiny idiosyncrasies of this
|
|
* function, just like they did with AMX Mod X.
|
|
*
|
|
* There are explicitly more cases than the AMX Mod X version because
|
|
* we're not doing a blind copy. Each case is specifically optimized
|
|
* for what needs to be done. Even better, we don't have to error on
|
|
* bad buffer sizes. Instead, this function will smartly cut off the
|
|
* string in a way that pushes old data out.
|
|
*/
|
|
char *UTIL_ReplaceEx(char *subject, size_t maxLen, const char *search, size_t searchLen, const char *replace, size_t replaceLen, bool caseSensitive)
|
|
{
|
|
char *ptr = subject;
|
|
size_t browsed = 0;
|
|
size_t textLen = strlen(subject);
|
|
|
|
/* It's not possible to search or replace */
|
|
if (searchLen > textLen)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
/* Handle the case of one byte replacement.
|
|
* It's only valid in one case.
|
|
*/
|
|
if (maxLen == 1)
|
|
{
|
|
/* If the search matches and the replace length is 0,
|
|
* we can just terminate the string and be done.
|
|
*/
|
|
if ((caseSensitive ? strcmp(subject, search) : stricmp(subject, search)) == 0 && replaceLen == 0)
|
|
{
|
|
*subject = '\0';
|
|
return subject;
|
|
}
|
|
else
|
|
{
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
/* Subtract one off the maxlength so we can include the null terminator */
|
|
maxLen--;
|
|
|
|
while (*ptr != '\0' && (browsed <= textLen - searchLen))
|
|
{
|
|
/* See if we get a comparison */
|
|
if ((caseSensitive ? strncmp(ptr, search, searchLen) : strnicmp(ptr, search, searchLen)) == 0)
|
|
{
|
|
if (replaceLen > searchLen)
|
|
{
|
|
/* First, see if we have enough space to do this operation */
|
|
if (maxLen - textLen < replaceLen - searchLen)
|
|
{
|
|
/* First, see if the replacement length goes out of bounds. */
|
|
if (browsed + replaceLen >= maxLen)
|
|
{
|
|
/* EXAMPLE CASE:
|
|
* Subject: AABBBCCC
|
|
* Buffer : 12 bytes
|
|
* Search : BBB
|
|
* Replace: DDDDDDDDDD
|
|
* OUTPUT : AADDDDDDDDD
|
|
* POSITION: ^
|
|
*/
|
|
/* If it does, we'll just bound the length and do a strcpy. */
|
|
replaceLen = maxLen - browsed;
|
|
|
|
/* Note, we add one to the final result for the null terminator */
|
|
strncopy(ptr, replace, replaceLen + 1);
|
|
|
|
/* Don't truncate a multi-byte character */
|
|
if (*(ptr + replaceLen - 1) & 1 << 7)
|
|
{
|
|
replaceLen -= UTIL_CheckValidChar(ptr + replaceLen - 1);
|
|
*(ptr + replaceLen) = '\0';
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* EXAMPLE CASE:
|
|
* Subject: AABBBCCC
|
|
* Buffer : 12 bytes
|
|
* Search : BBB
|
|
* Replace: DDDDDDD
|
|
* OUTPUT : AADDDDDDDCC
|
|
* POSITION: ^
|
|
*/
|
|
/* We're going to have some bytes left over... */
|
|
size_t origBytesToCopy = (textLen - (browsed + searchLen)) + 1;
|
|
size_t realBytesToCopy = (maxLen - (browsed + replaceLen)) + 1;
|
|
char *moveFrom = ptr + searchLen + (origBytesToCopy - realBytesToCopy);
|
|
char *moveTo = ptr + replaceLen;
|
|
|
|
/* First, move our old data out of the way. */
|
|
memmove(moveTo, moveFrom, realBytesToCopy);
|
|
|
|
/* Now, do our replacement. */
|
|
memcpy(ptr, replace, replaceLen);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* EXAMPLE CASE:
|
|
* Subject: AABBBCCC
|
|
* Buffer : 12 bytes
|
|
* Search : BBB
|
|
* Replace: DDDD
|
|
* OUTPUT : AADDDDCCC
|
|
* POSITION: ^
|
|
*/
|
|
/* Yes, we have enough space. Do a normal move operation. */
|
|
char *moveFrom = ptr + searchLen;
|
|
char *moveTo = ptr + replaceLen;
|
|
|
|
/* First move our old data out of the way. */
|
|
size_t bytesToCopy = (textLen - (browsed + searchLen)) + 1;
|
|
memmove(moveTo, moveFrom, bytesToCopy);
|
|
|
|
/* Now do our replacement. */
|
|
memcpy(ptr, replace, replaceLen);
|
|
}
|
|
}
|
|
else if (replaceLen < searchLen)
|
|
{
|
|
/* EXAMPLE CASE:
|
|
* Subject: AABBBCCC
|
|
* Buffer : 12 bytes
|
|
* Search : BBB
|
|
* Replace: D
|
|
* OUTPUT : AADCCC
|
|
* POSITION: ^
|
|
*/
|
|
/* If the replacement does not grow the string length, we do not
|
|
* need to do any fancy checking at all. Yay!
|
|
*/
|
|
char *moveFrom = ptr + searchLen; /* Start after the search pointer */
|
|
char *moveTo = ptr + replaceLen; /* Copy to where the replacement ends */
|
|
|
|
/* Copy our replacement in, if any */
|
|
if (replaceLen)
|
|
{
|
|
memcpy(ptr, replace, replaceLen);
|
|
}
|
|
|
|
/* Figure out how many bytes to move down, including null terminator */
|
|
size_t bytesToCopy = (textLen - (browsed + searchLen)) + 1;
|
|
|
|
/* Move the rest of the string down */
|
|
memmove(moveTo, moveFrom, bytesToCopy);
|
|
}
|
|
else
|
|
{
|
|
/* EXAMPLE CASE:
|
|
* Subject: AABBBCCC
|
|
* Buffer : 12 bytes
|
|
* Search : BBB
|
|
* Replace: DDD
|
|
* OUTPUT : AADDDCCC
|
|
* POSITION: ^
|
|
*/
|
|
/* We don't have to move anything around, just do a straight copy */
|
|
memcpy(ptr, replace, replaceLen);
|
|
}
|
|
|
|
return ptr + replaceLen;
|
|
}
|
|
ptr++;
|
|
browsed++;
|
|
}
|
|
|
|
return NULL;
|
|
} |