Subversion Repositories planix.SVN

/*
 *      upas/unesc - interpret =?foo?bar?=char?= escapes
 */
#include <u.h>
#include <libc.h>
#include <bio.h>

int
hex(int c)
{
        if('0' <= c && c <= '9')
                return c - '0';
        if('a' <= c && c <= 'f')
                return c - 'a' + 10;
        if('A' <= c && c <= 'F')
                return c - 'A' + 10;
        return 0;
}

void
main(void)
{
        int c;
        Biobuf bin, bout;

        Binit(&bin,  0, OREAD);
        Binit(&bout, 1, OWRITE);
        while((c = Bgetc(&bin)) != Beof)
                if(c != '=')
                        Bputc(&bout, c);
                else if((c = Bgetc(&bin)) != '?'){
                        Bputc(&bout, '=');
                        Bputc(&bout, c);
                } else {
                        while((c = Bgetc(&bin)) != Beof && c != '?')
                                continue;               /* consume foo */
                        while((c = Bgetc(&bin)) != Beof && c != '?')
                                continue;               /* consume bar */
                        while((c = Bgetc(&bin)) != Beof && c != '?'){
                                if(c == '='){
                                        c  = hex(Bgetc(&bin)) << 4;
                                        c |= hex(Bgetc(&bin));
                                }
                                Bputc(&bout, c);
                        }
                        c = Bgetc(&bin);                /* consume '=' */
                        if (c != '=')   
                                Bungetc(&bin);
                }
        Bterm(&bout);
        exits(0);
}