| /* vi: set sw=4 ts=4: */ |
| /* |
| * Mini tr implementation for busybox |
| * |
| ** Copyright (c) 1987,1997, Prentice Hall All rights reserved. |
| * |
| * The name of Prentice Hall may not be used to endorse or promote |
| * products derived from this software without specific prior |
| * written permission. |
| * |
| * Copyright (c) Michiel Huisjes |
| * |
| * This version of tr is adapted from Minix tr and was modified |
| * by Erik Andersen <andersen@codepoet.org> to be used in busybox. |
| * |
| * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. |
| */ |
| /* http://www.opengroup.org/onlinepubs/009695399/utilities/tr.html |
| * TODO: graph, print |
| */ |
| #include "libbb.h" |
| |
| enum { |
| ASCII = 256, |
| /* string buffer needs to be at least as big as the whole "alphabet". |
| * BUFSIZ == ASCII is ok, but we will realloc in expand |
| * even for smallest patterns, let's avoid that by using *2: |
| */ |
| TR_BUFSIZ = (BUFSIZ > ASCII*2) ? BUFSIZ : ASCII*2, |
| }; |
| |
| static void map(char *pvector, |
| char *string1, unsigned string1_len, |
| char *string2, unsigned string2_len) |
| { |
| char last = '0'; |
| unsigned i, j; |
| |
| for (j = 0, i = 0; i < string1_len; i++) { |
| if (string2_len <= j) |
| pvector[(unsigned char)(string1[i])] = last; |
| else |
| pvector[(unsigned char)(string1[i])] = last = string2[j++]; |
| } |
| } |
| |
| /* supported constructs: |
| * Ranges, e.g., 0-9 ==> 0123456789 |
| * Escapes, e.g., \a ==> Control-G |
| * Character classes, e.g. [:upper:] ==> A...Z |
| * Equiv classess, e.g. [=A=] ==> A (hmmmmmmm?) |
| */ |
| static unsigned expand(const char *arg, char **buffer_p) |
| { |
| char *buffer = *buffer_p; |
| unsigned pos = 0; |
| unsigned size = TR_BUFSIZ; |
| unsigned i; /* can't be unsigned char: must be able to hold 256 */ |
| unsigned char ac; |
| |
| while (*arg) { |
| if (pos + ASCII > size) { |
| size += ASCII; |
| *buffer_p = buffer = xrealloc(buffer, size); |
| } |
| if (*arg == '\\') { |
| arg++; |
| buffer[pos++] = bb_process_escape_sequence(&arg); |
| continue; |
| } |
| if (arg[1] == '-') { /* "0-9..." */ |
| ac = arg[2]; |
| if (ac == '\0') { /* "0-": copy verbatim */ |
| buffer[pos++] = *arg++; /* copy '0' */ |
| continue; /* next iter will copy '-' and stop */ |
| } |
| i = (unsigned char) *arg; |
| while (i <= ac) /* ok: i is unsigned _int_ */ |
| buffer[pos++] = i++; |
| arg += 3; /* skip 0-9 */ |
| continue; |
| } |
| if ((ENABLE_FEATURE_TR_CLASSES || ENABLE_FEATURE_TR_EQUIV) |
| && *arg == '[' |
| ) { |
| arg++; |
| i = (unsigned char) *arg++; |
| /* "[xyz...". i=x, arg points to y */ |
| if (ENABLE_FEATURE_TR_CLASSES && i == ':') { /* [:class:] */ |
| #define CLO ":]\0" |
| static const char classes[] ALIGN1 = |
| "alpha"CLO "alnum"CLO "digit"CLO |
| "lower"CLO "upper"CLO "space"CLO |
| "blank"CLO "punct"CLO "cntrl"CLO |
| "xdigit"CLO; |
| enum { |
| CLASS_invalid = 0, /* we increment the retval */ |
| CLASS_alpha = 1, |
| CLASS_alnum = 2, |
| CLASS_digit = 3, |
| CLASS_lower = 4, |
| CLASS_upper = 5, |
| CLASS_space = 6, |
| CLASS_blank = 7, |
| CLASS_punct = 8, |
| CLASS_cntrl = 9, |
| CLASS_xdigit = 10, |
| //CLASS_graph = 11, |
| //CLASS_print = 12, |
| }; |
| smalluint j; |
| char *tmp; |
| |
| /* xdigit needs 8, not 7 */ |
| i = 7 + (arg[0] == 'x'); |
| tmp = xstrndup(arg, i); |
| j = index_in_strings(classes, tmp) + 1; |
| free(tmp); |
| |
| if (j == CLASS_invalid) |
| goto skip_bracket; |
| |
| arg += i; |
| if (j == CLASS_alnum || j == CLASS_digit || j == CLASS_xdigit) { |
| for (i = '0'; i <= '9'; i++) |
| buffer[pos++] = i; |
| } |
| if (j == CLASS_alpha || j == CLASS_alnum || j == CLASS_upper) { |
| for (i = 'A'; i <= 'Z'; i++) |
| buffer[pos++] = i; |
| } |
| if (j == CLASS_alpha || j == CLASS_alnum || j == CLASS_lower) { |
| for (i = 'a'; i <= 'z'; i++) |
| buffer[pos++] = i; |
| } |
| if (j == CLASS_space || j == CLASS_blank) { |
| buffer[pos++] = '\t'; |
| if (j == CLASS_space) { |
| buffer[pos++] = '\n'; |
| buffer[pos++] = '\v'; |
| buffer[pos++] = '\f'; |
| buffer[pos++] = '\r'; |
| } |
| buffer[pos++] = ' '; |
| } |
| if (j == CLASS_punct || j == CLASS_cntrl) { |
| for (i = '\0'; i < ASCII; i++) { |
| if ((j == CLASS_punct && isprint(i) && !isalnum(i) && !isspace(i)) |
| || (j == CLASS_cntrl && iscntrl(i)) |
| ) { |
| buffer[pos++] = i; |
| } |
| } |
| } |
| if (j == CLASS_xdigit) { |
| for (i = 'A'; i <= 'F'; i++) { |
| buffer[pos + 6] = i | 0x20; |
| buffer[pos++] = i; |
| } |
| pos += 6; |
| } |
| continue; |
| } |
| /* "[xyz...", i=x, arg points to y */ |
| if (ENABLE_FEATURE_TR_EQUIV && i == '=') { /* [=CHAR=] */ |
| buffer[pos++] = *arg; /* copy CHAR */ |
| if (!arg[0] || arg[1] != '=' || arg[2] != ']') |
| bb_show_usage(); |
| arg += 3; /* skip CHAR=] */ |
| continue; |
| } |
| /* The rest of "[xyz..." cases is treated as normal |
| * string, "[" has no special meaning here: |
| * tr "[a-z]" "[A-Z]" can be written as tr "a-z" "A-Z", |
| * also try tr "[a-z]" "_A-Z+" and you'll see that |
| * [] is not special here. |
| */ |
| skip_bracket: |
| arg -= 2; /* points to "[" in "[xyz..." */ |
| } |
| buffer[pos++] = *arg++; |
| } |
| return pos; |
| } |
| |
| /* NB: buffer is guaranteed to be at least TR_BUFSIZE |
| * (which is >= ASCII) big. |
| */ |
| static int complement(char *buffer, int buffer_len) |
| { |
| int len; |
| char conv[ASCII]; |
| unsigned char ch; |
| |
| len = 0; |
| ch = '\0'; |
| while (1) { |
| if (memchr(buffer, ch, buffer_len) == NULL) |
| conv[len++] = ch; |
| if (++ch == '\0') |
| break; |
| } |
| memcpy(buffer, conv, len); |
| return len; |
| } |
| |
| int tr_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
| int tr_main(int argc UNUSED_PARAM, char **argv) |
| { |
| int i; |
| smalluint flags; |
| ssize_t read_chars; |
| size_t in_index, out_index; |
| unsigned last = UCHAR_MAX + 1; /* not equal to any char */ |
| unsigned char coded, c; |
| char *str1 = xmalloc(TR_BUFSIZ); |
| char *str2 = xmalloc(TR_BUFSIZ); |
| int str2_length; |
| int str1_length; |
| char *vector = xzalloc(ASCII * 3); |
| char *invec = vector + ASCII; |
| char *outvec = vector + ASCII * 2; |
| |
| #define TR_OPT_complement (1 << 0) |
| #define TR_OPT_delete (1 << 1) |
| #define TR_OPT_squeeze_reps (1 << 2) |
| |
| for (i = 0; i < ASCII; i++) { |
| vector[i] = i; |
| /*invec[i] = outvec[i] = FALSE; - done by xzalloc */ |
| } |
| |
| opt_complementary = "-1"; |
| flags = getopt32(argv, "+cds"); /* '+': stop at first non-option */ |
| argv += optind; |
| |
| str1_length = expand(*argv++, &str1); |
| str2_length = 0; |
| if (flags & TR_OPT_complement) |
| str1_length = complement(str1, str1_length); |
| if (*argv) { |
| if (argv[0][0] == '\0') |
| bb_error_msg_and_die("STRING2 cannot be empty"); |
| str2_length = expand(*argv, &str2); |
| map(vector, str1, str1_length, |
| str2, str2_length); |
| } |
| for (i = 0; i < str1_length; i++) |
| invec[(unsigned char)(str1[i])] = TRUE; |
| for (i = 0; i < str2_length; i++) |
| outvec[(unsigned char)(str2[i])] = TRUE; |
| |
| goto start_from; |
| |
| /* In this loop, str1 space is reused as input buffer, |
| * str2 - as output one. */ |
| for (;;) { |
| /* If we're out of input, flush output and read more input. */ |
| if ((ssize_t)in_index == read_chars) { |
| if (out_index) { |
| xwrite(STDOUT_FILENO, str2, out_index); |
| start_from: |
| out_index = 0; |
| } |
| read_chars = safe_read(STDIN_FILENO, str1, TR_BUFSIZ); |
| if (read_chars <= 0) { |
| if (read_chars < 0) |
| bb_perror_msg_and_die(bb_msg_read_error); |
| break; |
| } |
| in_index = 0; |
| } |
| c = str1[in_index++]; |
| if ((flags & TR_OPT_delete) && invec[c]) |
| continue; |
| coded = vector[c]; |
| if ((flags & TR_OPT_squeeze_reps) && last == coded |
| && (invec[c] || outvec[coded]) |
| ) { |
| continue; |
| } |
| str2[out_index++] = last = coded; |
| } |
| |
| return EXIT_SUCCESS; |
| } |