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#include "textcode.h"
#include "haveinline.h"
static inline int dec(unsigned char x) {
if (x>='A' && x<='Z') return x-'A';
if (x>='a' && x<='z') return x-'a'+26;
if (x>='0' && x<='9') return x-'0'+26+26;
switch (x) {
case '+': return 62;
case '/': return 63;
default: return -1;
}
}
unsigned long scan_base64(const char *src,char *dest,unsigned long *destlen) {
unsigned short tmp=0,bits=0;
register const unsigned char* s=(const unsigned char*) src;
const char* orig=dest;
for (;;) {
int a=dec(*s);
if (a<0) {
while (*s=='=') ++s;
break;
}
tmp=(tmp<<6)|a; bits+=6;
++s;
if (bits>=8) {
*dest=(tmp>>(bits-=8));
++dest;
}
}
*destlen=dest-orig;
return (const char*)s-src;
}
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