1 /* vi: set sw=4 ts=4: */
5 * Copyright (C) Manuel Novoa III <mjn3@codepoet.org>
6 * and Vladimir Oleynik <dzo@simtreas.ru>
8 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
12 #define WANT_HEX_ESCAPES 1
14 /* Usual "this only works for ascii compatible encodings" disclaimer. */
16 #define _tolower(X) ((X)|((char) 0x20))
18 char FAST_FUNC bb_process_escape_sequence(const char **ptr)
29 if (WANT_HEX_ESCAPES && *q == 'x') {
35 /* bash requires leading 0 in octal escapes:
36 * \02 works, \2 does not (prints \ and 2).
37 * We treat \2 as a valid octal escape sequence. */
40 unsigned d = (unsigned char)(*q) - '0';
43 d = (unsigned char)_tolower(*q) - 'a';
45 /* The above would map 'A'-'F' and 'a'-'f' to 10-15,
46 * however, some chars like '@' would map to 9 < base.
47 * Do not allow that, map invalid chars to N > base:
54 if (WANT_HEX_ESCAPES && base == 16) {
56 if (num_digits == 0) {
57 /* \x<bad_char>: return '\',
58 * leave ptr pointing to x */
72 } while (++num_digits < 3);
74 if (num_digits == 0) {
75 /* Not octal or hex escape sequence.
76 * Is it one-letter one? */
78 /* bash builtin "echo -e '\ec'" interprets \e as ESC,
79 * but coreutils "/bin/echo -e '\ec'" does not.
80 * Manpages tend to support coreutils way.
81 * Update: coreutils added support for \e on 28 Oct 2009. */
82 static const char charmap[] ALIGN1 = {
83 'a', 'b', 'e', 'f', 'n', 'r', 't', 'v', '\\', '\0',
84 '\a', '\b', 27, '\f', '\n', '\r', '\t', '\v', '\\', '\\',
86 const char *p = charmap;
92 } while (*++p != '\0');
93 /* p points to found escape char or NUL,
94 * advance it and find what it translates to.
95 * Note that \NUL and unrecognized sequence \z return '\'
96 * and leave ptr pointing to NUL or z. */
97 n = p[sizeof(charmap) / 2];
105 char* FAST_FUNC strcpy_and_process_escape_sequences(char *dst, const char *src)
111 c1 = bb_process_escape_sequence(&src);