wc.c

   1 /*
   2  * Mini wc implementation for busybox
   3  *
   4  * by Edward Betts <edward@debian.org>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  19  *
  20  */
  21
  22 #include "internal.h"
  23 #include <stdio.h>
  24
  25 static const char wc_usage[] = "wc [OPTION]... [FILE]...\n\n"
  26 "Print line, word, and byte counts for each FILE, and a total line if\n"
  27 "more than one FILE is specified.  With no FILE, read standard input.\n"
  28 "\t-c\tprint the byte counts\n"
  29 "\t-l\tprint the newline counts\n"
  30 "\t-L\tprint the length of the longest line\n"
  31 "\t-w\tprint the word counts\n";
  32
  33 static int total_lines, total_words, total_chars, max_length;
  34 static int print_lines, print_words, print_chars, print_length;
  35
  36 void print_counts (int lines, int words, int chars, int length,
  37                 const char *name) {
  38         char const *space = "";
  39         if (print_lines) {
  40                 printf ("%7d", lines);
  41                 space = " ";
  42         }
  43         if (print_words) {
  44                 printf ("%s%7d", space, words);
  45                 space = " ";
  46         }
  47         if (print_chars) {
  48                 printf ("%s%7d", space, chars);
  49                 space = " ";
  50         }
  51         if (print_length)
  52                 printf ("%s%7d", space, length);
  53         if (*name)
  54                 printf (" %s", name);
  55         putchar ('\n');
  56 }
  57
  58 static void wc_file(FILE *file, const char *name)
  59 {
  60         int lines, words, chars, length;
  61         int in_word = 0, linepos = 0;
  62         int c;
  63         lines = words = chars = length = 0;
  64         while ((c = getc(file)) != EOF) {
  65                 chars++;
  66                 switch (c) {
  67                         case '\n':
  68                                 lines++;
  69                         case '\r':
  70                         case '\f':
  71                                 if (linepos > length)
  72                                         length = linepos;
  73                                 linepos = 0;
  74                                 goto word_separator;
  75                         case '\t':
  76                                 linepos += 8 - (linepos % 8);
  77                                 goto word_separator;
  78                         case ' ':
  79                                 linepos++;
  80                         case '\v':
  81                         word_separator:
  82                                 if (in_word) {
  83                                         in_word = 0;
  84                                         words++;
  85                                 }
  86                                 break;
  87                         default:
  88                                 linepos++;
  89                                 in_word = 1;
  90                                 break;
  91                 }
  92         }
  93         if (linepos > length)
  94                 length = linepos;
  95         if (in_word)
  96                 words++;
  97         print_counts (lines, words, chars, length, name);
  98         total_lines += lines;
  99         total_words += words;
 100         total_chars += chars;
 101         if (length > max_length)
 102                 max_length = length;
 103         fclose(file);
 104         fflush(stdout);
 105 }
 106
 107 int wc_main(int argc, char **argv) {
 108         FILE *file;
 109         total_lines = total_words = total_chars = max_length = 0;
 110         print_lines = print_words = print_chars = print_length = 0;
 111
 112         while (--argc && **(++argv) == '-') {
 113                 while (*++(*argv))
 114                         switch (**argv) {
 115                                 case 'c':
 116                                         print_chars = 1;
 117                                         break;
 118                                 case 'l':
 119                                         print_lines = 1;
 120                                         break;
 121                                 case 'L':
 122                                         print_length = 1;
 123                                         break;
 124                                 case 'w':
 125                                         print_words = 1;
 126                                         break;
 127                                 default:
 128                                         usage (wc_usage);
 129                         }
 130         }
 131
 132         if (!print_lines && !print_words && !print_chars && !print_length)
 133                 print_lines = print_words = print_chars = 1;
 134
 135         if (argc == 0) {
 136                 wc_file(stdin, "");
 137                 exit(TRUE);
 138         }
 139         else if (argc == 1) {
 140                 file = fopen(*argv, "r");
 141                 if (file == NULL) {
 142                         perror(*argv);
 143                         exit(FALSE);
 144                 }
 145                 wc_file(file, *argv);
 146         }
 147         else {
 148                 while (argc-- > 0 && *argv != '\0' && strlen(*argv)) {
 149                         file = fopen(*argv, "r");
 150                         if (file == NULL) {
 151                                 perror(*argv);
 152                                 exit(FALSE);
 153                         }
 154                         wc_file(file, *argv);
 155                         argv++;
 156                 }
 157                 print_counts (total_lines, total_words, total_chars,
 158                                 max_length, "total");
 159         }
 160         exit(TRUE);
 161 }