usr/src/cmd/look/look.c

   1 /*
   2  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
   3  * Use is subject to license terms.
   4  */
   5
   6 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
   7 /*        All Rights Reserved   */
   8
   9 /*
  10  * Copyright (c) 1980 Regents of the University of California.
  11  * All rights reserved. The Berkeley software License Agreement
  12  * specifies the terms and conditions for redistribution.
  13  */
  14
  15 #pragma ident   "%Z%%M% %I%     %E% SMI"
  16
  17 #include <stdio.h>
  18 #include <ctype.h>
  19 #include <string.h>
  20
  21 FILE *dfile;
  22 char *filenam  = "/usr/share/lib/dict/words";
  23
  24 int fold;
  25 int dict;
  26 int tab;
  27 #define WORDSIZE 257
  28 char entry[WORDSIZE];
  29 char word[WORDSIZE];
  30 char key[WORDSIZE];
  31
  32 int     compare(char *, char *);
  33 void    canon(char *, char *);
  34 int     getword(char *);
  35
  36 int
  37 main(int argc, char **argv)
  38 {
  39         int c;
  40         long top,bot,mid;
  41         char *wstring, *ptr;
  42
  43         while(argc>=2 && *argv[1]=='-') {
  44                 for(;;) {
  45                         switch(*++argv[1]) {
  46                         case 'd':
  47                                 dict++;
  48                                 continue;
  49                         case 'f':
  50                                 fold++;
  51                                 continue;
  52                         case 't':
  53                                 tab = argv[1][1];
  54                                 if(tab)
  55                                         ++argv[1];
  56                                 continue;
  57                         case 0:
  58                                 break;
  59                         default:
  60                                 continue;
  61                         }
  62                         break;
  63                 }
  64                 argc --;
  65                 argv++;
  66         }
  67         if(argc<=1)
  68                 return (1);
  69         if(argc==2) {
  70                 fold++;
  71                 dict++;
  72         } else
  73                 filenam = argv[2];
  74         dfile = fopen(filenam,"r");
  75         if(dfile==NULL) {
  76                 fprintf(stderr,"look: can't open %s\n",filenam);
  77                 exit(2);
  78         }
  79         wstring = strdup(argv[1]);
  80         if (tab != NULL) {
  81                 if ((ptr = strchr(wstring, tab)) != NULL) {
  82                         *++ptr = '\0';
  83                 }
  84         }
  85         canon(wstring,key);
  86         bot = 0;
  87         fseek(dfile,0L,2);
  88         top = ftell(dfile);
  89         for(;;) {
  90                 mid = (top+bot)/2;
  91                 fseek(dfile,mid,0);
  92                 do {
  93                         c = getc(dfile);
  94                         mid++;
  95                 } while(c!=EOF && c!='\n');
  96                 if(!getword(entry))
  97                         break;
  98                 canon(entry,word);
  99                 switch(compare(key,word)) {
 100                 case -2:
 101                 case -1:
 102                 case 0:
 103                         if(top<=mid)
 104                                 break;
 105                         top = mid;
 106                         continue;
 107                 case 1:
 108                 case 2:
 109                         bot = mid;
 110                         continue;
 111                 }
 112                 break;
 113         }
 114         fseek(dfile,bot,0);
 115         while(ftell(dfile)<top) {
 116                 if(!getword(entry))
 117                         return (0);
 118                 canon(entry,word);
 119                 switch(compare(key,word)) {
 120                 case -2:
 121                         return (0);
 122                 case -1:
 123                 case 0:
 124                         puts(entry);
 125                         break;
 126                 case 1:
 127                 case 2:
 128                         continue;
 129                 }
 130                 break;
 131         }
 132         while(getword(entry)) {
 133                 canon(entry,word);
 134                 switch(compare(key,word)) {
 135                 case -1:
 136                 case 0:
 137                         puts(entry);
 138                         continue;
 139                 }
 140                 break;
 141         }
 142         return (0);
 143 }
 144
 145 int
 146 compare(char *s, char *t)
 147 {
 148         for(;*s==*t;s++,t++)
 149                 if(*s==0)
 150                         return(0);
 151         return(*s==0? -1:
 152                 *t==0? 1:
 153                 *s<*t? -2:
 154                 2);
 155 }
 156
 157 int
 158 getword(char *w)
 159 {
 160         int c;
 161         int avail = WORDSIZE - 1;
 162
 163         while(avail--) {
 164                 c = getc(dfile);
 165                 if(c==EOF)
 166                         return(0);
 167                 if(c=='\n')
 168                         break;
 169                 *w++ = c;
 170         }
 171         while (c != '\n')
 172                 c = getc(dfile);
 173         *w = 0;
 174         return(1);
 175 }
 176
 177 void
 178 canon(char *old, char *new)
 179 {
 180         int c;
 181         int avail = WORDSIZE - 1;
 182
 183         for(;;) {
 184                 *new = c = *old++;
 185                 if(c==0) {
 186                         *new = 0;
 187                         break;
 188                 }
 189                 if(dict) {
 190                         if(!isalnum(c))
 191                                 continue;
 192                 }
 193                 if(fold) {
 194                         if(isupper(c))
 195                                 *new += 'a' - 'A';
 196                 }
 197                 new++;
 198                 avail--;
 199                 if (avail <= 0) {
 200                         *new = 0;
 201                         break;
 202                 }
 203         }
 204 }