libowfat/textcode/fmt_quotedprintable_sa.c

#include "fmt.h"
#include "stralloc.h"
#include "textcode.h"
#include "haveinline.h"

static inline int tohex(char c) {
  return c>9?c-10+'A':c+'0';
}

int fmt_quotedprintable_sa(stralloc* sa,const char* src,unsigned int len) {
  register const unsigned char* s=(const unsigned char*) src;
  unsigned long i;
  for (i=0; i<len; ++i) {
    if (s[i]&0x80 || s[i]=='=') {
      char dest[3]={'='};

      dest[1]=tohex(s[i]>>4);
      dest[2]=tohex(s[i]&15);
      if (!stralloc_catb(sa, dest, 3)) return 0;
    } else {
      if (!stralloc_catb(sa, s + i, 1)) return 0;
    }
  }
  return 1;
}