*: introduce and use FAST_FUNC: regparm on i386, otherwise no-on

[oweals/busybox.git] / libbb / process_escape_sequence.c

diff --git a/libbb/process_escape_sequence.c b/libbb/process_escape_sequence.c
index f5ac500fafb42e6f5f05a502a5af558fb6a30b9f..4d03bd61f34641db39c956e6deec5045dd494e4b 100644 (file)
--- a/libbb/process_escape_sequence.c
+++ b/libbb/process_escape_sequence.c
@@ -5,30 +5,20 @@
  * 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
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
- *
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  */
 
-#include <stdio.h>
-#include <limits.h>
 #include "libbb.h"
 
-char bb_process_escape_sequence(const char **ptr)
+#define WANT_HEX_ESCAPES 1
+
+/* Usual "this only works for ascii compatible encodings" disclaimer. */
+#undef _tolower
+#define _tolower(X) ((X)|((char) 0x20))
+
+char FAST_FUNC bb_process_escape_sequence(const char **ptr)
 {
-       static const char charmap[] = {
+       static const char charmap[] ALIGN1 = {
                'a',  'b',  'f',  'n',  'r',  't',  'v',  '\\', 0,
                '\a', '\b', '\f', '\n', '\r', '\t', '\v', '\\', '\\' };
 
@@ -37,24 +27,47 @@ char bb_process_escape_sequence(const char **ptr)
        unsigned int num_digits;
        unsigned int r;
        unsigned int n;
+       unsigned int d;
+       unsigned int base;
 
-       n = 0;
+       num_digits = n = 0;
+       base = 8;
        q = *ptr;
 
-       num_digits = 0;
+#ifdef WANT_HEX_ESCAPES
+       if (*q == 'x') {
+               ++q;
+               base = 16;
+               ++num_digits;
+       }
+#endif
+
        do {
-               if (((unsigned int)(*q - '0')) <= 7) {
-                       r = n * 8 + (*q - '0');
-                       if (r <= UCHAR_MAX) {
-                               n = r;
-                               ++q;
-                               if (++num_digits < 3) {
-                                       continue;
-                               }
+               d = (unsigned char)(*q) - '0';
+#ifdef WANT_HEX_ESCAPES
+               if (d >= 10) {
+                       d = (unsigned char)(_tolower(*q)) - 'a' + 10;
+               }
+#endif
+
+               if (d >= base) {
+#ifdef WANT_HEX_ESCAPES
+                       if ((base == 16) && (!--num_digits)) {
+/*                             return '\\'; */
+                               --q;
                        }
+#endif
+                       break;
+               }
+
+               r = n * base + d;
+               if (r > UCHAR_MAX) {
+                       break;
                }
-               break;
-       } while (1);
+
+               n = r;
+               ++q;
+       } while (++num_digits < 3);
 
        if (num_digits == 0) {  /* mnemonic escape sequence? */
                p = charmap;
@@ -64,18 +77,10 @@ char bb_process_escape_sequence(const char **ptr)
                                break;
                        }
                } while (*++p);
-               n = *(p+(sizeof(charmap)/2));
+               n = *(p + (sizeof(charmap)/2));
        }
 
        *ptr = q;
+
        return (char) n;
 }
-
-/* END CODE */
-/*
-Local Variables:
-c-file-style: "linux"
-c-basic-offset: 4
-tab-width: 4
-End:
-*/