Dataset storage (#866)

* Store active dataset and pending dataset in non-volatile memory.

  * Retrieve active dataset and pending dataset from non-volatile memory after each reboot.

  * Leader will generate the active dataset if it is not initialized.

  * Clear pending dataset after it replaces active dataset.

  * Create different pseudo flash files for posix nodes.

examples/platforms/cc2538/platform.c

@@ -33,6 +33,7 @@
  */
 
 #include <platform/uart.h>
+#include <platform/flash.h>
 #include "platform-cc2538.h"
 
 otInstance *sInstance;
@@ -43,6 +44,7 @@ void PlatformInit(int argc, char *argv[])
     cc2538RandomInit();
     cc2538RadioInit();
     otPlatUartEnable();
+    otPlatFlashInit();
 
     (void)argc;
     (void)argv;

examples/platforms/posix/flash-windows-stubs.c

@@ -0,0 +1,59 @@
+/*
+ *  Copyright (c) 2016, The OpenThread Authors.
+ *  All rights reserved.
+ *
+ *  Redistribution and use in source and binary forms, with or without
+ *  modification, are permitted provided that the following conditions are met:
+ *  1. Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *  2. Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *  3. Neither the name of the copyright holder nor the
+ *     names of its contributors may be used to endorse or promote products
+ *     derived from this software without specific prior written permission.
+ *
+ *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ *  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ *  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ *  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ *  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ *  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ *  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ *  POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "platform-posix.h"
+
+ThreadError otPlatFlashInit(void)
+{
+    return kThreadError_NotImplemented;
+}
+
+uint32_t otPlatFlashGetSize(void)
+{
+    return 0;
+}
+
+ThreadError otPlatFlashErasePage(uint32_t aAddress)
+{
+    return kThreadError_NotImplemented;
+}
+
+ThreadError otPlatFlashStatusWait(uint32_t aTimeout)
+{
+    return kThreadError_None;
+}
+
+uint32_t otPlatFlashWrite(uint32_t aAddress, uint8_t *aData, uint32_t aSize)
+{
+    return 0;
+}
+
+uint32_t otPlatFlashRead(uint32_t aAddress, uint8_t *aData, uint32_t aSize)
+{
+    return 0;
+}

examples/platforms/posix/flash.c

@@ -53,9 +53,12 @@ enum
 ThreadError otPlatFlashInit(void)
 {
     ThreadError error = kThreadError_None;
-    char fileName[16];
+    char fileName[20];
     struct stat st;
     bool create = false;
+    struct timeval tv;
+
+    gettimeofday(&tv, NULL);
 
     memset(&st, 0, sizeof(st));
 
@@ -64,7 +67,7 @@ ThreadError otPlatFlashInit(void)
         mkdir("tmp", 0777);
     }
 
-    snprintf(fileName, sizeof(fileName), "tmp/%d.flash", NODE_ID);
+    snprintf(fileName, sizeof(fileName), "tmp/%d_%d.flash", NODE_ID, (uint32_t)tv.tv_usec);
 
     if (access(fileName, 0))
     {

examples/platforms/posix/platform.c

@@ -43,6 +43,7 @@
 
 #include <openthread.h>
 #include <platform/alarm.h>
+#include <platform/flash.h>
 #include <platform/uart.h>
 
 uint32_t NODE_ID = 1;
@@ -68,6 +69,7 @@ void PlatformInit(int argc, char *argv[])
     platformAlarmInit();
     platformRadioInit();
     platformRandomInit();
+    otPlatFlashInit();
 }
 
 bool UartInitialized = false;