/*
* Utility routines.
*
- * Copyright (C) tons of folks. Tracking down who wrote what
- * isn't something I'm going to worry about... If you wrote something
- * here, please feel free to acknowledge your work.
+ * Copyright (C) Manuel Novoa III <mjn3@codepoet.org>
+ * and Vladimir Oleynik <dzo@simtreas.ru>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
- * Based in part on code from sash, Copyright (c) 1999 by David I. Bell
- * Permission has been granted to redistribute this code under the GPL.
*
*/
#include <stdio.h>
#include <limits.h>
+#include <ctype.h>
#include "libbb.h"
+#define WANT_HEX_ESCAPES 1
+/* Usual "this only works for ascii compatible encodings" disclaimer. */
+#undef _tolower
+#define _tolower(X) ((X)|((char) 0x20))
-char process_escape_sequence(char **ptr)
+char bb_process_escape_sequence(const char **ptr)
{
- static const char charmap[] = {
- 'a', 'b', 'f', 'n', 'r', 't', 'v', '\\', 0,
- '\a', '\b', '\f', '\n', '\r', '\t', '\v', '\\', '\\' };
+ static const char charmap[] = {
+ 'a', 'b', 'f', 'n', 'r', 't', 'v', '\\', 0,
+ '\a', '\b', '\f', '\n', '\r', '\t', '\v', '\\', '\\' };
- const char *p;
- char *q;
- int num_digits;
- unsigned int n;
+ const char *p;
+ const char *q;
+ unsigned int num_digits;
+ unsigned int r;
+ unsigned int n;
+ unsigned int d;
+ unsigned int base;
- n = 0;
- q = *ptr;
+ num_digits = n = 0;
+ base = 8;
+ q = *ptr;
- for ( num_digits = 0 ; num_digits < 3 ; ++num_digits) {
- if ((*q < '0') || (*q > '7')) { /* not a digit? */
- break;
- }
- n = n * 8 + (*q++ - '0');
- }
+#ifdef WANT_HEX_ESCAPES
+ if (*q == 'x') {
+ ++q;
+ base = 16;
+ ++num_digits;
+ }
+#endif
- if (num_digits == 0) { /* mnemonic escape sequence? */
- for (p=charmap ; *p ; p++) {
- if (*p == *q) {
- q++;
- break;
- }
- }
- n = *(p+(sizeof(charmap)/2));
- }
+ do {
+ d = (unsigned int)(*q - '0');
+#ifdef WANT_HEX_ESCAPES
+ if (d >= 10) {
+ d = ((unsigned int)(_tolower(*q) - 'a')) + 10;
+ }
+#endif
- /* doesn't hurt to fall through to here from mnemonic case */
- if (n > UCHAR_MAX) { /* is octal code too big for a char? */
- n /= 8; /* adjust value and */
- --q; /* back up one char */
- }
+ if (d >= base) {
+#ifdef WANT_HEX_ESCAPES
+ if ((base == 16) && (!--num_digits)) {
+/* return '\\'; */
+ --q;
+ }
+#endif
+ break;
+ }
- *ptr = q;
- return (char) n;
-}
+ r = n * base + d;
+ if (r > UCHAR_MAX) {
+ break;
+ }
+
+ n = r;
+ ++q;
+ } while (++num_digits < 3);
+
+ if (num_digits == 0) { /* mnemonic escape sequence? */
+ p = charmap;
+ do {
+ if (*p == *q) {
+ q++;
+ break;
+ }
+ } while (*++p);
+ n = *(p+(sizeof(charmap)/2));
+ }
+ *ptr = q;
+
+ return (char) n;
+}
/* END CODE */
/*