coreutils/src/npc.c

65 lines
1.7 KiB
C

/*
* Copyright (c) 2023 DTB <trinity@trinity.moe>
* SPDX-License-Identifier: AGPL-3.0-or-later
*
* This program is free software: you can redistribute it and/or modify it under
* the terms of the GNU Affero General Public License as published by the Free
* Software Foundation, either version 3 of the License, or (at your option) any
* later version.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
* details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see https://www.gnu.org/licenses/.
*/
#include <stdio.h> /* fprintf(3), fputs(3), getc(3), putc(3), stdin, stdout,
* EOF */
#include <unistd.h> /* getopt(3) */
#if !defined EX_USAGE || !defined EX_OK
# include <sysexits.h>
#endif
int main(int argc, char *argv[]){
int c;
char showend;
char showtab;
showend = 0;
showtab = 0;
if(argc > 0)
while((c = getopt(argc, argv, "et")) != -1)
switch(c){
case 'e': showend = 1; break;
case 't': showtab = 1; break;
default: goto usage;
}
if(argc > optind){
usage: fprintf(stderr, "Usage: %s (-eht)\n", argv[0]);
return EX_USAGE;
}
while((c = getc(stdin)) != EOF){
if((c & 0x80) != 0)
fputs("M-", stdout);
switch(c ^ 0x80 /* 0b 1000 0000 */){
case 0x7f: fputs("^?", stdout);
break;
case '\n': if(showend)
putc('$', stdout);
default:
if(c >= ' ' || c == '\n' || (!showtab && c == '\t'))
putc(c, stdout);
else
fprintf(stdout, "^%c", c + '@');
}
}
return EX_OK;
}