first draft

hstring.c

@@ -0,0 +1,80 @@
+/* hstring.c - Random string-related functions for hping.
+ * Copyright(C) 2003 Salvatore Sanfilippo
+ * All rights reserved */
+
+#include <sys/types.h>
+#include <string.h>
+#include <ctype.h>
+
+/* return 1 if the string looks like an integer number
+ * otherwise 0 is returned.
+ *
+ * this function is equivalent to this regexp:
+ *		[:space:]*-{0,1}[0-9]+[:space:]*
+ * in english:
+ *  (0-inf spaces)(zero or one -)(1-inf digits)(0-inf spaces)
+ */
+int strisnum(char *s)
+{
+	int digits = 0; /* used to return false if there aren't digits */
+
+	while(isspace(*s))
+		s++; /* skip initial spaces */
+	if (*s == '-') /* negative number? */
+		s++;
+	while(*s) {
+		if (isspace(*s)) { /* skip spaces in the tail */
+			while(isspace(*s))
+				s++;
+			if (*s) return 0; /* but don't allow other tail chars */
+			return digits ? 1 : 0;
+		}
+		if (!isdigit(*s))
+			return 0;
+		s++;
+		digits++;
+	}
+	return digits ? 1 : 0;
+}
+
+/* function similar to strtok() more convenient when we know the
+ * max number of tokens, to tokenize with a single call.
+ * Unlike strtok(), strftok() is thread safe.
+ *
+ * ARGS:
+ *   'sep' is a string that contains all the delimiter characters
+ *   'str' is the string to tokenize, that will be modified
+ *   'tptrs' is an array of char* poiters that will contain the token pointers
+ *   'nptrs' is the length of the 'tptrs' array.
+ *
+ * RETURN VALUE:
+ *   The number of extracted tokens is returned.
+ */
+size_t strftok(char *sep, char *str, char **tptrs, size_t nptrs)
+{
+	size_t seplen = strlen(sep);
+	size_t i, j = 0;
+	int inside = 0;
+
+	while(*str) {
+		for(i = 0; i < seplen; i++) {
+			if (sep[i] == *str)
+				break;
+		}
+		if (i == seplen) { /* no match */
+			if (!inside) {
+				tptrs[j++] = str;
+				inside = 1;
+			}
+		} else { /* match */
+			if (inside) {
+				*str = '\0';
+				if (j == nptrs)
+					return j;
+				inside = 0;
+			}
+		}
+		str++;
+	}
+	return j;
+}