Diff: utility/stoip4.c

Revision:

14:7648334eb41b

diff -r 95c00132cd98 -r 7648334eb41b utility/stoip4.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/utility/stoip4.c	Tue Sep 03 09:16:55 2019 +0000
@@ -0,0 +1,79 @@
+/*
+ * Copyright (c) 2014-2018 ARM Limited. All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ * Licensed under the Apache License, Version 2.0 (the License); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an AS IS BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include "mbed_version.h"
+
+#if MBED_MAJOR_VERSION == 2
+
+#include <string.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include "common_functions.h"
+#include "ip4string.h"
+
+/**
+ * Convert numeric IPv4 address string to a binary.
+ * \param ip4addr IPv4 address in string format.
+ * \param len Length of IPv4 string, maximum of 16..
+ * \param dest buffer for address. MUST be 4 bytes.
+ * \return boolean set to true if conversion succeded, false if it didn't
+ */
+bool stoip4(const char *ip4addr, size_t len, void *dest)
+{
+    uint8_t *addr = dest;
+
+    if (len > 16) { // Too long, not possible
+        return false;
+    }
+
+    uint_fast8_t stringLength = 0, byteCount = 0;
+
+    //Iterate over each component of the IP. The exit condition is in the middle of the loop
+    while (true) {
+
+        //No valid character (IPv4 addresses don't have implicit 0, that is x.y..z being read as x.y.0.z)
+        if (stringLength == len || ip4addr[stringLength] < '0' || ip4addr[stringLength] > '9') {
+            return false;
+        }
+
+        //For each component, we convert it to the raw value
+        uint_fast16_t byte = 0;
+        while (stringLength < len && ip4addr[stringLength] >= '0' && ip4addr[stringLength] <= '9') {
+            byte *= 10;
+            byte += ip4addr[stringLength++] - '0';
+
+            //We go over the maximum value for an IPv4 component
+            if (byte > 0xff) {
+                return false;
+            }
+        }
+
+        //Append the component
+        addr[byteCount++] = (uint8_t) byte;
+
+        //If we're at the end, we leave the loop. It's the only way to reach the `true` output
+        if (byteCount == 4) {
+            break;
+        }
+
+        //If the next character is invalid, we return false
+        if (stringLength == len || ip4addr[stringLength++] != '.') {
+            return false;
+        }
+    }
+
+    return stringLength == len || ip4addr[stringLength] == '\0';
+}
+#endif