1 /* 2 * Copyright (c) 1988 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 */ 7 8 #ifndef lint 9 char copyright[] = 10 "@(#) Copyright (c) 1988 The Regents of the University of California.\n\ 11 All rights reserved.\n"; 12 #endif /* not lint */ 13 14 #ifndef lint 15 static char sccsid[] = "@(#)tr.c 4.7 (Berkeley) 07/23/90"; 16 #endif /* not lint */ 17 18 #include <sys/types.h> 19 #include <stdio.h> 20 #include <ctype.h> 21 22 #define NCHARS 256 /* size of u_char */ 23 #define OOBCH 257 /* out of band value */ 24 25 typedef struct { 26 char *str; 27 int lastch, endrange; 28 enum { NORM, INRANGE, EOS } state; 29 } STR; 30 31 main(argc, argv) 32 int argc; 33 char **argv; 34 { 35 extern int optind; 36 STR s1, s2; 37 register int ch, indx, lastch; 38 int cflag, dflag, sflag; 39 u_char *tp, tab[NCHARS], squeeze[NCHARS]; 40 41 cflag = dflag = sflag = 0; 42 while ((ch = getopt(argc, argv, "cds")) != EOF) 43 switch((char)ch) { 44 case 'c': 45 cflag = 1; 46 break; 47 case 'd': 48 dflag = 1; 49 break; 50 case 's': 51 sflag = 1; 52 break; 53 case '?': 54 default: 55 fprintf(stderr, 56 "usage: tr [-cds] [string1 [string2]]\n"); 57 exit(1); 58 } 59 argc -= optind; 60 argv += optind; 61 62 /* 63 * the original tr was amazingly tolerant of the command line. 64 * Neither -c or -s have any effect unless there are two strings. 65 * Extra arguments are silently ignored. Bag this noise, they 66 * should all be errors. 67 */ 68 if (argc < 2 && !dflag) { 69 while ((ch = getchar()) != EOF) 70 putchar(ch); 71 exit(0); 72 } 73 74 bzero(tab, NCHARS); 75 if (sflag) { 76 s1.str = argv[1]; 77 s1.state = NORM; 78 s1.lastch = OOBCH; 79 while (next(&s1)) 80 squeeze[s1.lastch] = 1; 81 } 82 if (dflag) { 83 s1.str = argv[0]; 84 s1.state = NORM; 85 s1.lastch = OOBCH; 86 while (next(&s1)) 87 tab[s1.lastch] = 1; 88 if (cflag) 89 for (tp = tab, indx = 0; indx < NCHARS; ++tp, ++indx) 90 *tp = !*tp; 91 if (sflag) 92 for (lastch = OOBCH; (ch = getchar()) != EOF;) { 93 if (tab[ch] || (squeeze[ch] && lastch == ch)) 94 continue; 95 lastch = ch; 96 putchar(ch); 97 } 98 else 99 while ((ch = getchar()) != EOF) 100 if (!tab[ch]) 101 putchar(ch); 102 } else { 103 s1.str = argv[0]; 104 s2.str = argv[1]; 105 s1.state = s2.state = NORM; 106 s1.lastch = s2.lastch = OOBCH; 107 if (cflag) { 108 /* 109 * if cflag is set, tr just pretends it only got one 110 * character in string2. As reasonable as anything 111 * else. Should really be an error. 112 */ 113 while (next(&s2)); 114 lastch = s2.lastch; 115 for (tp = tab, indx = 0; indx < NCHARS; ++tp, ++indx) 116 *tp = lastch; 117 while (next(&s1)) 118 tab[s1.lastch] = s1.lastch; 119 } else { 120 for (tp = tab, indx = 0; indx < NCHARS; ++tp, ++indx) 121 *tp = indx; 122 while (next(&s1)) { 123 (void)next(&s2); 124 tab[s1.lastch] = s2.lastch; 125 } 126 } 127 if (sflag) 128 for (lastch = OOBCH; (ch = getchar()) != EOF;) { 129 ch = tab[ch]; 130 if (squeeze[ch] && lastch == ch) 131 continue; 132 lastch = ch; 133 putchar(ch); 134 } 135 else 136 while ((ch = getchar()) != EOF) 137 putchar((int)tab[ch]); 138 } 139 exit(0); 140 } 141 142 next(s) 143 register STR *s; 144 { 145 register int ch; 146 147 if (s->state == EOS) 148 return(0); 149 if (s->state == INRANGE) { 150 if (++s->lastch == s->endrange) 151 s->state = NORM; 152 return(1); 153 } 154 if (!(ch = *s->str++)) { 155 s->state = EOS; 156 return(0); 157 } 158 if (ch == '\\') { /* \### */ 159 s->lastch = tran(s); 160 return(1); 161 } 162 if (ch == '-') { /* ranges */ 163 if (s->lastch == OOBCH) /* "-a" */ 164 goto fail2; 165 if (!(ch = *s->str++)) /* "a-" */ 166 goto fail1; 167 if (ch == '\\') /* \### */ 168 ch = tran(s); 169 if (s->lastch > ch) { /* "z-a" */ 170 fail1: --s->str; 171 fail2: s->lastch = '-'; 172 return(1); 173 } 174 if (s->lastch == ch) /* "a-a" */ 175 return(next(s)); 176 s->state = INRANGE; /* "a-z" */ 177 s->endrange = ch; 178 return(1); 179 } 180 s->lastch = ch; 181 return(1); 182 } 183 184 /* 185 * Translate \-escapes. Up to 3 octal digits => char; no digits => literal. 186 * Unadorned backslash "\" is like \000. 187 */ 188 tran(s) 189 register STR *s; 190 { 191 register int ch, cnt = 0, val = 0; 192 193 for (;;) { 194 ch = *s->str++; 195 if (!isascii(ch) || !isdigit(ch) || ++cnt > 3) 196 break; 197 val = val * 8 + ch - '0'; 198 } 199 if (cnt || ch == 0) 200 s->str--; 201 return (cnt ? val : ch); 202 } 203