1 files changed, 93 insertions, 0 deletions
diff --git a/tools/libxutil/lexis.c b/tools/libxutil/lexis.c
new file mode 100644
index 0000000000..26d2ec4d5b
--- /dev/null
+++ b/tools/libxutil/lexis.c
@@ -0,0 +1,93 @@
+/*
+ *
+ * This library is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2.1 of the
+ * License, or  (at your option) any later version. This library 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 Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+/** @file
+ * Lexical analysis.
+ */
+
+#include "sys_string.h"
+#include "lexis.h"
+#include <errno.h>
+
+/** Check if a value lies in a (closed) range.
+ *
+ * @param x value to test
+ * @param lo low end of the range
+ * @param hi high end of the range
+ * @return 1 if x is in the interval [lo, hi], 0 otherwise
+ */
+inline static int in_range(int x, int lo, int hi){
+    return (lo <= x) && (x <= hi);
+}
+
+/** Determine if a string is an (unsigned) decimal number.
+ * 
+ * @param s pointer to characters to test
+ * @param n length of string
+ * @return 1 if s is a decimal number, 0 otherwise.
+ */
+int is_decimal_number(const char *s, int n){
+    int i;
+    if(n <= 0)return 0;
+    for(i = 0; i < n; i++){
+        if(!in_decimal_digit_class(s[i])) return 0;
+    }
+    return 1;
+}
+
+/** Determine if a string is a hex number.
+ * Hex numbers are 0, or start with 0x or 0X followed
+ * by a non-zero number of hex digits (0-9,a-f,A-F).
+ * 
+ * @param s pointer to characters to test
+ * @param n length of string
+ * @return 1 if s is a hex number, 0 otherwise.
+ */
+int is_hex_number(const char *s, int n){
+    int i;
+    if(n <= 0) return 0;
+    if(n == 1){
+        return s[0]=='0';
+    }
+    if(n <= 3) return 0;
+    if(s[0] != '0' || (s[1] != 'x' && s[1] != 'X')) return 0;
+    for(i = 2; i < n; i++){
+        if(!in_hex_digit_class(s[i])) return 0;
+    }
+    return 1;
+}
+
+/** Test if a string matches a keyword.
+ * The comparison is case-insensitive.
+ * The comparison fails if either argument is null.
+ *
+ * @param s string
+ * @param k keyword
+ * @return 1 if they match, 0 otherwise
+ */
+int is_keyword(const char *s, const char *k){
+  return s && k && !strcasecmp(s, k);
+}
+
+/** Test if a string matches a character.
+ *
+ * @param s string
+ * @param c character (non-null)
+ * @return 1 if s contains exactly c, 0 otherwise
+ */
+int is_keychar(const char *s, char c){
+  return c && (s[0] == c) && !s[1];
+}