text-utils/colrm.c

   1 /*
   2  * Copyright (c) 1980 Regents of the University of California.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 /*
  35  * 1999-02-22 Arkadiusz Miśkiewicz <misiek@pld.ORG.PL>
  36  *      added Native Language Support
  37  * 1999-09-19 Bruno Haible <haible@clisp.cons.org>
  38  *      modified to work correctly in multi-byte locales
  39  */
  40
  41 #include <stdio.h>
  42 #include <stdlib.h>
  43 #include <getopt.h>
  44 #include <unistd.h>
  45
  46 #include "nls.h"
  47 #include "strutils.h"
  48 #include "c.h"
  49 #include "widechar.h"
  50 #include "closestream.h"
  51
  52 /*
  53 COLRM removes unwanted columns from a file
  54         Jeff Schriebman  UC Berkeley 11-74
  55 */
  56
  57 static void __attribute__ ((__noreturn__)) usage(FILE * out)
  58 {
  59         fprintf(out, _("\nUsage:\n"
  60                        " %s [startcol [endcol]]\n"),
  61                        program_invocation_short_name);
  62
  63         fputs(USAGE_SEPARATOR, out);
  64         fputs(_("Filter out the specified columns.\n"), out);
  65
  66         fputs(USAGE_OPTIONS, out);
  67         fputs(USAGE_HELP, out);
  68         fputs(USAGE_VERSION, out);
  69         fprintf(out, _("%s reads from standard input and writes to standard output\n\n"),
  70                        program_invocation_short_name);
  71         fprintf(out, USAGE_MAN_TAIL("colrm(1)"));
  72         exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS);
  73 }
  74
  75 static int process_input(unsigned long first, unsigned long last)
  76 {
  77         unsigned long ct = 0;
  78         wint_t c;
  79         unsigned long i;
  80         int w;
  81         int padding;
  82
  83         for (;;) {
  84                 c = getwc(stdin);
  85                 if (c == WEOF)
  86                         return 0;
  87                 if (c == '\t')
  88                         w = ((ct + 8) & ~7) - ct;
  89                 else if (c == '\b')
  90                         w = (ct ? ct - 1 : 0) - ct;
  91                 else {
  92                         w = wcwidth(c);
  93                         if (w < 0)
  94                                 w = 0;
  95                 }
  96                 ct += w;
  97                 if (c == '\n') {
  98                         putwc(c, stdout);
  99                         ct = 0;
 100                         continue;
 101
 102                 }
 103                 if (!first || ct < first) {
 104                         putwc(c, stdout);
 105                         continue;
 106                 }
 107                 break;
 108         }
 109
 110         for (i = ct - w + 1; i < first; i++)
 111                 putwc(' ', stdout);
 112
 113         /* Loop getting rid of characters */
 114         while (!last || ct < last) {
 115                 c = getwc(stdin);
 116                 if (c == WEOF)
 117                         return 0;
 118                 if (c == '\n') {
 119                         putwc(c, stdout);
 120                         return 1;
 121                 }
 122                 if (c == '\t')
 123                         ct = (ct + 8) & ~7;
 124                 else if (c == '\b')
 125                         ct = ct ? ct - 1 : 0;
 126                 else {
 127                         w = wcwidth(c);
 128                         if (w < 0)
 129                                 w = 0;
 130                         ct += w;
 131                 }
 132         }
 133
 134         padding = 0;
 135
 136         /* Output last of the line */
 137         for (;;) {
 138                 c = getwc(stdin);
 139                 if (c == WEOF)
 140                         break;
 141                 if (c == '\n') {
 142                         putwc(c, stdout);
 143                         return 1;
 144                 }
 145                 if (padding == 0 && last < ct) {
 146                         for (i = last; i < ct; i++)
 147                                 putwc(' ', stdout);
 148                         padding = 1;
 149                 }
 150                 putwc(c, stdout);
 151         }
 152         return 0;
 153 }
 154
 155 int main(int argc, char **argv)
 156 {
 157         unsigned long first = 0, last = 0;
 158         int opt;
 159
 160         static const struct option longopts[] = {
 161                 {"version", no_argument, NULL, 'V'},
 162                 {"help",    no_argument, NULL, 'h'},
 163                 {NULL, 0, NULL, 0}
 164         };
 165
 166         setlocale(LC_ALL, "");
 167         bindtextdomain(PACKAGE, LOCALEDIR);
 168         textdomain(PACKAGE);
 169         atexit(close_stdout);
 170
 171         while ((opt =
 172                 getopt_long(argc, argv, "bfhl:pxVH", longopts,
 173                             NULL)) != -1)
 174                 switch (opt) {
 175                 case 'V':
 176                         printf(UTIL_LINUX_VERSION);
 177                         return EXIT_SUCCESS;
 178                 case 'h':
 179                         usage(stdout);
 180                 default:
 181                         errtryhelp(EXIT_FAILURE);
 182                 }
 183
 184         if (argc > 1)
 185                 first = strtoul_or_err(*++argv, _("first argument"));
 186         if (argc > 2)
 187                 last = strtoul_or_err(*++argv, _("second argument"));
 188
 189         while (process_input(first, last))
 190                 ;
 191
 192         fflush(stdout);
 193         return EXIT_SUCCESS;
 194 }