Allow hex escape sequences

diff --git a/libbb/process_escape_sequence.c b/libbb/process_escape_sequence.c
index f5ac500..e6b5fc9 100644 (file)
--- a/libbb/process_escape_sequence.c
+++ b/libbb/process_escape_sequence.c
@@ -22,35 +22,42 @@
  *
  */
 
+#include <string.h>
 #include <stdio.h>
 #include <limits.h>
+#include <ctype.h>
 #include "libbb.h"
 
+#define isodigit(c) ((c) >= '0' && (c) <= '7')
+#define hextobin(c) ((c)>='a'&&(c)<='f' ? (c)-'a'+10 : (c)>='A'&&(c)<='F' ? (c)-'A'+10 : (c)-'0')
+#define octtobin(c) ((c) - '0')
 char bb_process_escape_sequence(const char **ptr)
 {
+       const char *p, *q;
+       unsigned int num_digits, r, n, hexescape;
        static const char charmap[] = {
                'a',  'b',  'f',  'n',  'r',  't',  'v',  '\\', 0,
                '\a', '\b', '\f', '\n', '\r', '\t', '\v', '\\', '\\' };
 
-       const char *p;
-       const char *q;
-       unsigned int num_digits;
-       unsigned int r;
-       unsigned int n;
-
-       n = 0;
+       n = r = hexescape = num_digits = 0;
        q = *ptr;
 
-       num_digits = 0;
+       if (*q == 'x') {
+               hexescape++;
+               ++q;
+       }
+
        do {
-               if (((unsigned int)(*q - '0')) <= 7) {
-                       r = n * 8 + (*q - '0');
-                       if (r <= UCHAR_MAX) {
-                               n = r;
-                               ++q;
-                               if (++num_digits < 3) {
-                                       continue;
-                               }
+               if (hexescape && isxdigit(*q)) {
+                       r = n * 16 + hextobin(*q);
+               } else if (isodigit(*q)) {
+                       r = n * 8 + octtobin(*q);
+               }
+               if (r <= UCHAR_MAX) {
+                       n = r;
+                       ++q;
+                       if (++num_digits < 3) {
+                               continue;
                        }
                }
                break;