1 /* tr.c - translate or delete characters 2 * 3 * Copyright 2014 Sandeep Sharma <sandeep.jack2756 (at) gmail.com> 4 * 5 * See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/tr.html 6 7 USE_TR(NEWTOY(tr, "^>2<1Ccsd[+cC]", TOYFLAG_USR|TOYFLAG_BIN)) 8 9 config TR 10 bool "tr" 11 default n 12 help 13 usage: tr [-cds] SET1 [SET2] 14 15 Translate, squeeze, or delete characters from stdin, writing to stdout 16 17 -c/-C Take complement of SET1 18 -d Delete input characters coded SET1 19 -s Squeeze multiple output characters of SET2 into one character 20 */ 21 22 #define FOR_tr 23 #include "toys.h" 24 25 GLOBALS( 26 short map[256]; //map of chars 27 int len1, len2; 28 ) 29 30 enum { 31 class_alpha, class_alnum, class_digit, 32 class_lower,class_upper,class_space,class_blank, 33 class_punct,class_cntrl,class_xdigit,class_invalid 34 }; 35 36 static void map_translation(char *set1 , char *set2) 37 { 38 int i = TT.len1, k = 0; 39 40 if (toys.optflags & FLAG_d) 41 for (; i; i--, k++) TT.map[set1[k]] = set1[k]|0x100; //set delete bit 42 43 if (toys.optflags & FLAG_s) { 44 for (i = TT.len1, k = 0; i; i--, k++) 45 TT.map[set1[k]] = TT.map[set1[k]]|0x200; 46 for (i = TT.len2, k = 0; i; i--, k++) 47 TT.map[set2[k]] = TT.map[set2[k]]|0x200; 48 } 49 i = k = 0; 50 while (!(toys.optflags & FLAG_d) && set2 && TT.len1--) { //ignore set2 if -d present 51 TT.map[set1[i]] = ((TT.map[set1[i]] & 0xFF00) | set2[k]); 52 if (set2[k + 1]) k++; 53 i++; 54 } 55 } 56 57 static int handle_escape_char(char **esc_val) //taken from printf 58 { 59 char *ptr = *esc_val; 60 int esc_length = 0; 61 unsigned base = 0, num = 0, result = 0, count = 0; 62 63 if (*ptr == 'x') { 64 ptr++; 65 esc_length++; 66 base = 16; 67 } else if (isdigit(*ptr)) base = 8; 68 69 while (esc_length < 3 && base) { 70 num = tolower(*ptr) - '0'; 71 if (num > 10) num += ('0' - 'a' + 10); 72 if (num >= base) { 73 if (base == 16) { 74 esc_length--; 75 if (!esc_length) {// Invalid hex value eg. /xvd, print as it is /xvd 76 result = '\\'; 77 ptr--; 78 } 79 } 80 break; 81 } 82 esc_length++; 83 count = result = (count * base) + num; 84 ptr++; 85 } 86 if (base) { 87 ptr--; 88 *esc_val = ptr; 89 return (char)result; 90 } else { 91 switch (*ptr) { 92 case 'n': result = '\n'; break; 93 case 't': result = '\t'; break; 94 case 'e': result = (char)27; break; 95 case 'b': result = '\b'; break; 96 case 'a': result = '\a'; break; 97 case 'f': result = '\f'; break; 98 case 'v': result = '\v'; break; 99 case 'r': result = '\r'; break; 100 case '\\': result = '\\'; break; 101 default : 102 result = '\\'; 103 ptr--; // Let pointer pointing to / we will increment after returning. 104 break; 105 } 106 } 107 *esc_val = ptr; 108 return (char)result; 109 } 110 111 static int find_class(char *class_name) 112 { 113 int i; 114 static char *class[] = { 115 "[:alpha:]","[:alnum:]","[:digit:]", 116 "[:lower:]","[:upper:]","[:space:]", 117 "[:blank:]","[:punct:]","[:cntrl:]", 118 "[:xdigit:]","NULL" 119 }; 120 121 for (i = 0; i != class_invalid; i++) { 122 if (!memcmp(class_name, class[i], (class_name[0] == 'x')?10:9)) break; 123 } 124 return i; 125 } 126 127 static char *expand_set(char *arg, int *len) 128 { 129 int i = 0, j, k, size = 256; 130 char *set = xzalloc(size*sizeof(char)); 131 132 while (*arg) { 133 134 if (i >= size) { 135 size += 256; 136 set = xrealloc(set, size); 137 } 138 if (*arg == '\\') { 139 arg++; 140 set[i++] = (int)handle_escape_char(&arg); 141 arg++; 142 continue; 143 } 144 if (arg[1] == '-') { 145 if (arg[2] == '\0') goto save; 146 j = arg[0]; 147 k = arg[2]; 148 if (j > k) perror_exit("reverse colating order"); 149 while (j <= k) set[i++] = j++; 150 arg += 3; 151 continue; 152 } 153 if (arg[0] == '[' && arg[1] == ':') { 154 155 if ((j = find_class(arg)) == class_invalid) goto save; 156 157 if ((j == class_alpha) || (j == class_upper) || (j == class_alnum)) { 158 for (k = 'A'; k <= 'Z'; k++) set[i++] = k; 159 } 160 if ((j == class_alpha) || (j == class_lower) || (j == class_alnum)) { 161 for (k = 'a'; k <= 'z'; k++) set[i++] = k; 162 } 163 if ((j == class_alnum) || (j == class_digit) || (j == class_xdigit)) { 164 for (k = '0'; k <= '9'; k++) set[i++] = k; 165 } 166 if (j == class_space || j == class_blank) { 167 set[i++] = '\t'; 168 if (j == class_space) { 169 set[i++] = '\n'; 170 set[i++] = '\f'; 171 set[i++] = '\r'; 172 set[i++] = '\v'; 173 } 174 set[i++] = ' '; 175 } 176 if (j == class_punct) { 177 for (k = 0; k <= 255; k++) 178 if (ispunct(k)) set[i++] = k; 179 } 180 if (j == class_cntrl) { 181 for (k = 0; k <= 255; k++) 182 if (iscntrl(k)) set[i++] = k; 183 } 184 if (j == class_xdigit) { 185 for (k = 'A'; k <= 'F'; k++) { 186 set[i + 6] = k | 0x20; 187 set[i++] = k; 188 } 189 i += 6; 190 arg += 10; 191 continue; 192 } 193 194 arg += 9; //never here for class_xdigit. 195 continue; 196 } 197 if (arg[0] == '[' && arg[1] == '=') { //[=char=] only 198 arg += 2; 199 if (*arg) set[i++] = *arg; 200 if (!arg[1] || arg[1] != '=' || arg[2] != ']') 201 error_exit("bad equiv class"); 202 continue; 203 } 204 save: 205 set[i++] = *arg++; 206 } 207 *len = i; 208 return set; 209 } 210 211 static void print_map(char *set1, char *set2) 212 { 213 int r = 0, i, prev_char = -1; 214 215 while (1) 216 { 217 i = 0; 218 r = read(STDIN_FILENO, (toybuf), sizeof(toybuf)); 219 if (!r) break; 220 for (;r > i;i++) { 221 222 if ((toys.optflags & FLAG_d) && (TT.map[(int)toybuf[i]] & 0x100)) continue; 223 if (toys.optflags & FLAG_s) { 224 if ((TT.map[(int)toybuf[i]] & 0x200) && 225 (prev_char == TT.map[(int)toybuf[i]])) { 226 continue; 227 } 228 } 229 xputc(TT.map[(int)toybuf[i]] & 0xFF); 230 prev_char = TT.map[(int)toybuf[i]]; 231 fflush(stdout); 232 } 233 } 234 } 235 236 static void do_complement(char **set) 237 { 238 int i, j; 239 char *comp = xmalloc(256); 240 241 for (i = 0, j = 0;i < 256; i++) { 242 if (memchr(*set, i, TT.len1)) continue; 243 else comp[j++] = (char)i; 244 } 245 free(*set); 246 TT.len1 = j; 247 *set = comp; 248 } 249 250 void tr_main(void) 251 { 252 char *set1, *set2 = NULL; 253 int i; 254 255 for (i = 0; i < 256; i++) TT.map[i] = i; //init map 256 257 set1 = expand_set(toys.optargs[0], &TT.len1); 258 if (toys.optflags & FLAG_c) do_complement(&set1); 259 if (toys.optargs[1]) { 260 if (toys.optargs[1][0] == '\0') error_exit("set2 can't be empty string"); 261 set2 = expand_set(toys.optargs[1], &TT.len2); 262 } 263 map_translation(set1, set2); 264 265 print_map(set1, set2); 266 free(set1); 267 free(set2); 268 } 269
