Changeset dce39b4 in mainline for uspace/lib/c/generic/str.c

Timestamp:

2012-07-29T23:06:56Z (12 years ago)

Author:

Martin Sucha <sucha14@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

0aa300d

Parents:

99047a72

Message:

Add a function to check if a string has a given prefix.

File:

• uspace/lib/c/generic/str.c (modified) (1 diff)

uspace/lib/c/generic/str.c

@@ -518 +518 @@
         return 0;
 
+}
+
+/** Test whether p is a prefix of s.
+ *
+ * Do a char-by-char comparison of two NULL-terminated strings
+ * and determine if p is a prefix of s.
+ *
+ * @param s The string in which to look
+ * @param p The string to check if it is a prefix of s
+ *
+ * @return true iff p is prefix of s else false
+ *
+ */
+bool str_test_prefix(const char *s, const char *p)
+{
+        wchar_t c1 = 0;
+        wchar_t c2 = 0;
+        
+        size_t off1 = 0;
+        size_t off2 = 0;
+
+        while (true) {
+                c1 = str_decode(s, &off1, STR_NO_LIMIT);
+                c2 = str_decode(p, &off2, STR_NO_LIMIT);
+                
+                if (c2 == 0)
+                        return true;
+
+                if (c1 != c2)
+                        return false;
+                
+                if (c1 == 0)
+                        break;
+        }
+
+        return false;
 }