/*
 * This library module implements the decoding of GSM7-encoded data
 * into ASCII, ISO 8859-1 or UTF-8.
 */

#include <sys/types.h>

extern u_short gsm7_decode_table[128];
extern u_short gsm7ext_decode_table[128];

gsm7_to_ascii_or_ext(inbuf, inlen, outbuf, outlenp, ascii_ext, newline_ok, errp)
	u_char *inbuf, *outbuf;
	unsigned inlen, *outlenp, *errp;
{
	u_char *inp, *endp, *outp;
	unsigned errcnt = 0;
	unsigned gsm, uni;

	inp = inbuf;
	endp = inbuf + inlen;
	outp = outbuf;
	while (inp < endp) {
		gsm = *inp++;
		if (gsm == 0x1B && inp < endp)
			uni = gsm7ext_decode_table[*inp++];
		else
			uni = gsm7_decode_table[gsm];
		if (uni == '\r') {
			*outp++ = '\\';
			*outp++ = 'r';
			errcnt++;
		} else if (uni == '\n') {
			if (newline_ok)
				*outp++ = '\n';
			else {
				*outp++ = '\\';
				*outp++ = 'n';
				errcnt++;
			}
		} else if (!uni || !is_decoded_char_ok(uni, ascii_ext)) {
			*outp++ = '?';
			errcnt++;
		} else if (ascii_ext == 2)
			outp += emit_utf8_char(uni, outp);
		else
			*outp++ = uni;
	}
	*outp = '\0';
	if (outlenp)
		*outlenp = outp - outbuf;
	if (errp)
		*errp = errcnt;
}