1
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forked from bonsai/harakit
coreutils/src/npc.c

91 lines
2.4 KiB
C

/*
* Copyright (c) 2023 DTB <trinity@trinity.moe>
* Copyright (c) 2024 Emma Tebibyte <emma@tebibyte.media>
* 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), perror(3), putc(3), stdin,
* stdout, EOF */
#include <sysexits.h> /* EX_IOERR, EX_OK, EX_OSERR, EX_USAGE */
#include <unistd.h> /* pledge(2), getopt(3) */
char *program_name = "npc";
static int
ioerr(char *argv0) {
perror(argv0);
return EX_IOERR;
}
static int
usage(char *argv0) {
(void)fprintf(stderr, "Usage: %s [-et]\n", argv0);
return EX_USAGE;
}
int main(int argc, char *argv[]) {
int c;
char showend = 0; /* print a dollar sign before each newline */
char showtab = 0; /* prints tab characters in caret notation */
#ifdef __OpenBSD__
if (pledge("stdio", NULL) == -1) {
perror(argv[0] == NULL ? program_name : argv[0]);
return EX_OSERR;
}
#endif
if (argc > 0) {
program_name = argv[0];
while ((c = getopt(argc, argv, "et")) != -1) {
switch (c){
case 'e': showend = 1; break;
case 't': showtab = 1; break;
default: return usage(program_name);
}
}
}
if (argc > optind) { return usage(program_name); }
while ((c = getc(stdin)) != EOF) {
if ((c & 0x80) != 0 && fputs("M-", stdout) == EOF) {
return ioerr(argv[0]);
}
switch (c ^ 0x80 /* 0b 1000 0000 */) {
case 0x7f: /* ASCII DEL (127d) */
if(fputs("^?", stdout) == EOF) { return ioerr(argv[0]); }
break;
case '\n':
if (showend && fputc('$', stdout) == EOF) {
return ioerr(argv[0]);
}
default:
if (c >= ' ' || c == '\n' || (!showtab && c == '\t')) {
if (fputc(c, stdout) == EOF) { return ioerr(argv[0]); }
} else if (fprintf(stdout, "^%c", c + '@') < 0) {
return ioerr(argv[0]);
}
}
}
return EX_OK;
}