minix/commands/prep/prep.c

   1 /* prep - prepare file for statistics   Author: Andy Tanenbaum */
   2
   3 #include <ctype.h>
   4 #include <stdlib.h>
   5 #include <stdio.h>
   6
   7 #define TROFF_CHAR      '.'     /* troff commands begin with this char */
   8 #define EOL             '\n'    /* end of line char */
   9 #define APOSTROPHE      047     /* single quote */
  10 #define BACKSLASH       '\\'    /* troff code */
  11
  12 int lfread;                     /* set when last char read was lf */
  13 int lfwritten = 1;              /* set when last char written was lf */
  14
  15 int main(int argc, char **argv);
  16 void skipline(void);
  17 int backslash(void);
  18 void usage(void);
  19
  20 int main(argc, argv)
  21 int argc;
  22 char *argv[];
  23 {
  24
  25   int c;
  26
  27   if (argc > 2) usage();
  28   if (argc == 2) {
  29         if (freopen(argv[1], "r", stdin) == NULL) {
  30                 printf("prep: cannot open %s\n", argv[1]);
  31                 exit(1);
  32         }
  33   }
  34   while ((c = getchar()) != EOF) {
  35         /* Lines beginning with "." are troff commands -- skip them. */
  36         if (lfread && c == TROFF_CHAR) {
  37                 skipline();
  38                 continue;
  39         }
  40         while (c == BACKSLASH) c = backslash(); /* eat troff stuff */
  41
  42         if (isupper(c)) {
  43                 putchar(tolower(c));
  44                 lfwritten = 0;
  45                 lfread = 0;
  46                 continue;
  47         }
  48         if (islower(c)) {
  49                 putchar(c);
  50                 lfwritten = 0;
  51                 lfread = 0;
  52                 continue;
  53         }
  54         if (c == APOSTROPHE) {
  55                 putchar(c);
  56                 lfwritten = 0;
  57                 lfread = 0;
  58                 continue;
  59         }
  60         lfread = (c == EOL ? 1 : 0);
  61         if (lfwritten) continue;
  62         putchar(EOL);
  63         lfwritten = 1;
  64   }
  65   return(0);
  66 }
  67
  68
  69 void skipline()
  70 {
  71   char c;
  72
  73   while ((c = getchar()) != EOL);
  74 }
  75
  76
  77 int backslash()
  78 {
  79 /* A backslash has been seen.  Eat troff stuff. */
  80
  81   int c, c1, c2;
  82
  83   c = getchar();
  84   switch (c) {
  85       case 'f':
  86         c = getchar();
  87         c = getchar();
  88         return(c);
  89
  90       case 's':                 /* \s7  or \s14 */
  91         c = getchar();
  92         c = getchar();
  93         if (isdigit(c)) c = getchar();
  94         return(c);
  95
  96       case 'n':                 /* \na or \n(xx  */
  97         c = getchar();
  98         if (c == '(') {
  99                 c = getchar();
 100                 c = getchar();
 101         }
 102         c = getchar();
 103         return(c);
 104
 105       case '*':                 /* / * (XX */
 106         c = getchar();
 107         if (c == '(') {
 108                 c = getchar();
 109                 c = getchar();
 110                 c = getchar();
 111                 return(c);
 112         }
 113
 114       case '(':                 /* troff 4-character escape sequence */
 115         c1 = getchar();
 116         c2 = getchar();
 117         if (c1 == 'e' && c2 == 'm') return(' ');
 118         if (c1 == 'e' && c2 == 'n') return(' ');
 119         c = getchar();
 120         return(c);
 121
 122       case '%':                 /* soft hyphen: \% */
 123         c = getchar();
 124         return(c);
 125
 126       default:
 127         return(c);
 128
 129   }
 130 }
 131
 132 void usage()
 133 {
 134   printf("Usage: prep [file]\n");
 135   exit(1);
 136 }