xnu-3789.60.24.tar.gz

[apple/xnu.git] / bsd / libkern / url_encode.c

diff --git a/bsd/libkern/url_encode.c b/bsd/libkern/url_encode.c
new file mode 100644 (file)
index 0000000..28534ad
--- /dev/null
+++ b/bsd/libkern/url_encode.c
@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2016 Apple Inc. All rights reserved.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
+ */
+
+#include <libkern/libkern.h>
+
+static int
+hex2int(int c)
+{
+       if (c >= '0' && c <= '9') {
+               return c - '0';
+       } else if (c >= 'A' && c <= 'F') {
+               return c - 'A' + 10;
+       } else if (c >= 'a' && c <= 'f') {
+               return c - 'a' + 10;
+       }
+       return 0;
+}
+
+static bool
+isprint(int ch)
+{
+       return ch >= 0x20 && ch <= 0x7e;
+}
+
+/*
+ * In-place decode of URL percent-encoded str
+ */
+void
+url_decode(char *str)
+{
+       if (!str) {
+               return;
+       }
+
+       while (*str) {
+               if (*str == '%') {
+                       char c = 0;
+                       char *esc = str++; /* remember the start of the escape sequence */
+
+                       if (*str) {
+                               c += hex2int(*str++);
+                       }
+                       if (*str) {
+                               c = (c << 4) + hex2int(*str++);
+                       }
+
+                       if (isprint(c)) {
+                               /* overwrite the '%' with the new char, and bump the rest of the
+                                * string down a few characters */
+                               *esc++ = c;
+                               str = memmove(esc, str, strlen(str)+1);
+                       } else {
+                               str++;
+                       }
+
+               } else {
+                       str++;
+               }
+       }
+}