Diff: uniqueid_stub.c

Revision:

1:9190c0f4d23a

Child:

6:c55b013dfc2a

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/uniqueid_stub.c	Sun Apr 24 16:41:14 2016 -0700
@@ -0,0 +1,76 @@
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+#include <stdlib.h>
+#include <stdint.h>
+#include "azure_c_shared_utility/uniqueid.h"
+#include "azure_c_shared_utility/iot_logging.h"
+#include <time.h>
+
+DEFINE_ENUM_STRINGS(UNIQUEID_RESULT, UNIQUEID_RESULT_VALUES);
+
+static const char tochar[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
+static void generate128BitUUID(unsigned char* arrayOfByte)
+{
+    size_t arrayIndex;
+
+    for (arrayIndex = 0; arrayIndex < 16; arrayIndex++)
+    {
+        arrayOfByte[arrayIndex] = (unsigned char)rand();
+    }
+
+    //
+    // Stick in the version field for random uuid.
+    //
+    arrayOfByte[7] &= 0x0f; //clear the bit field
+    arrayOfByte[7] |= 0x40; //set the ones we care about
+
+    //
+    // Stick in the variant field for the random uuid.
+    //
+    arrayOfByte[8] &= 0xf3; // Clear
+    arrayOfByte[8] |= 0x08; // Set
+
+}
+
+// TODO: The User will need to call srand before calling this function
+UNIQUEID_RESULT UniqueId_Generate(char* uid, size_t len)
+{
+    UNIQUEID_RESULT result;
+    unsigned char arrayOfChar[16];
+
+    /* Codes_SRS_UNIQUEID_07_002: [If uid is NULL then UniqueId_Generate shall return UNIQUEID_INVALID_ARG] */
+    /* Codes_SRS_UNIQUEID_07_003: [If len is less then 37 then UniqueId_Generate shall return UNIQUEID_INVALID_ARG] */
+    if (uid == NULL || len < 37)
+    {
+        result = UNIQUEID_INVALID_ARG;
+        LogError("Buffer Size is Null or length is less then 37 bytes");
+    }
+    else 
+    {
+        size_t arrayIndex;
+        size_t shiftCount;
+        size_t characterPosition = 0;
+
+        /* Codes_SRS_UNIQUEID_07_001: [UniqueId_Generate shall create a unique Id 36 character long string.] */
+        generate128BitUUID(arrayOfChar);
+        for (arrayIndex = 0; arrayIndex < 16; arrayIndex++)
+        {
+            for (shiftCount = 0; shiftCount <= 1; shiftCount++)
+            {
+                char hexChar = tochar[arrayOfChar[arrayIndex] & 0xf];
+                if ((characterPosition == 8) || (characterPosition == 13) || (characterPosition == 18) || (characterPosition == 23))
+                {
+                    uid[characterPosition] = '-';
+                    characterPosition++;
+                }
+                uid[characterPosition] = hexChar;
+                characterPosition++;
+                arrayOfChar[arrayIndex] = arrayOfChar[arrayIndex] >> 4;
+            }
+        }
+        uid[characterPosition] = 0;
+        result = UNIQUEID_OK;
+    }
+    return result;
+}