/* $OpenBSD: colrm.c,v 1.13 2016/10/27 12:53:54 schwarze Exp $ */ /* $NetBSD: colrm.c,v 1.4 1995/09/02 05:51:37 jtc Exp $ */ /*- * Copyright (c) 1991, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include <sys/types.h> #include <err.h> #include <errno.h> #include <limits.h> #include <locale.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <wchar.h> #define TAB 8 void usage(void); int main(int argc, char *argv[]) { char *line, *p; ssize_t linesz; wchar_t wc; u_long column, newcol, start, stop; int ch, len, width; setlocale(LC_CTYPE, ""); if (pledge("stdio", NULL) == -1) err(1, "pledge"); while ((ch = getopt(argc, argv, "")) != -1) switch(ch) { case '?': default: usage(); } argc -= optind; argv += optind; start = stop = 0; switch(argc) { case 2: stop = strtol(argv[1], &p, 10); if (stop <= 0 || *p) errx(1, "illegal column -- %s", argv[1]); /* FALLTHROUGH */ case 1: start = strtol(argv[0], &p, 10); if (start <= 0 || *p) errx(1, "illegal column -- %s", argv[0]); break; case 0: break; default: usage(); } if (stop && start > stop) err(1, "illegal start and stop columns"); line = NULL; while (getline(&line, &linesz, stdin) != -1) { column = 0; width = 0; for (p = line; *p != '\0'; p += len) { len = 1; switch (*p) { case '\n': putchar('\n'); continue; case '\b': /* * Pass it through if the previous character * was in scope, still represented by the * current value of "column". * Allow an optional second backspace * after a double-width character. */ if (start == 0 || column < start || (stop > 0 && column > stop + (width > 1))) { putchar('\b'); if (width > 1 && p[1] == '\b') putchar('\b'); } if (width > 1 && p[1] == '\b') p++; column -= width; continue; case '\t': newcol = (column + TAB) & ~(TAB - 1); if (start == 0 || newcol < start) { putchar('\t'); column = newcol; } else /* * Expand tabs that intersect or * follow deleted columns. */ while (column < newcol) if (++column < start || (stop > 0 && column > stop)) putchar(' '); continue; default: break; } /* * Handle the three cases of invalid bytes, * non-printable, and printable characters. */ if ((len = mbtowc(&wc, p, MB_CUR_MAX)) == -1) { (void)mbtowc(NULL, NULL, MB_CUR_MAX); len = 1; width = 1; } else if ((width = wcwidth(wc)) == -1) width = 1; /* * If the character completely fits before or * after the cut, keep it; otherwise, skip it. */ if ((start == 0 || column + width < start || (stop > 0 && column + (width > 0) > stop))) fwrite(p, 1, len, stdout); /* * If the cut cuts the character in half * and no backspace follows, * print a blank for correct columnation. */ else if (width > 1 && p[len] != '\b' && (start == 0 || column + 1 < start || (stop > 0 && column + width > stop))) putchar(' '); column += width; } } if (ferror(stdin)) err(1, "stdin"); if (ferror(stdout)) err(1, "stdout"); return 0; } void usage(void) { (void)fprintf(stderr, "usage: colrm [start [stop]]\n"); exit(1); }