Diff: IothubSerial.cpp

Revision:

17:0dbcbd8587fd

Parent:

13:ffeff9b5e513

--- a/IothubSerial.cpp	Tue Jan 19 20:18:23 2016 +0000
+++ b/IothubSerial.cpp	Fri Jan 22 01:35:07 2016 +0000
@@ -96,7 +96,77 @@
         return -1;
 }
 
-// try to serialize one or more measurements into the buffer
+
+// try to serialize a snapshot into the buffer
+// return bytes used / -1 if buffer too small / 0 if no data
+// current serialization is a json object with time and array per measure
+// eg: { "time": "2016-01-23T14:55:02", "temp": [1, 2], "volt": [12.1, 12.2] }
+int IothubSerial::MeasureSnapshotToString(MeasureSnapshot& msnap, char* buf, int bufsize)
+{
+    int slen;
+    int startlen = bufsize;
+
+    slen = sprintf_s(buf, bufsize, "{");
+    if (slen > 0)
+    {
+        bufsize -= slen;
+        buf += slen;
+    }
+    else
+        return -1;
+
+    slen = AddTime(msnap.Created, buf, bufsize);
+    if (slen > 0)
+    {
+        bufsize -= slen;
+        buf += slen;
+    }
+    else
+        return -1;
+
+    slen = MeasureGroupToString(msnap.Temps, buf, bufsize);
+    if (slen > 0)
+    {
+        bufsize -= slen;
+        buf += slen;
+    }
+    else
+        return -1;
+
+    slen = MeasureGroupToString(msnap.Positions, buf, bufsize);
+    if (slen > 0)
+    {
+        bufsize -= slen;
+        buf += slen;
+    }
+    else
+        return -1;
+
+    slen = MeasureGroupToString(msnap.Loads, buf, bufsize);
+    if (slen > 0)
+    {
+        bufsize -= slen;
+        buf += slen;
+    }
+    else
+        return -1;
+
+    slen = MeasureGroupToString(msnap.Volts, buf, bufsize);
+    if (slen > 0)
+    {
+        bufsize -= slen;
+        buf += slen;
+    }
+    else
+        return -1;
+
+    // replace final ',' with '}'
+    *(buf - 1) = '}';
+    
+    return startlen - bufsize;
+}
+
+// try to serialize one or more measurement snapshots into the buffer
 // return bytes used / -1 if buffer too small / 0 if no data
 // current serialization is a json array of objects with time and array per measure
 // eg: [{ "time": "2016-01-23T14:55:02", "temp": [1, 2], "volt": [12.1, 12.2] }]
@@ -106,14 +176,9 @@
     bool hasdata = false;
     bool copydata = false;
     char* startbuf = buf;
-    bool settime = false;
     char* lastcomma = NULL;
     
-    time_t secs = 0;
-    // reserve 1 space for end
-    bufsize--;
-    
-    slen = sprintf_s(buf, bufsize, "[{");
+    slen = sprintf_s(buf, bufsize, "[");
     if (slen > 0)
     {
         bufsize -= slen;
@@ -125,28 +190,26 @@
     if (_hasPending)
     {
         hasdata = true;
-        secs = _pending.Created;
-        slen = AddTime(secs, buf, bufsize);
+        slen = MeasureSnapshotToString(_pending, buf, bufsize);
         if (slen > 0)
         {
             bufsize -= slen;
             buf += slen;
-            settime = true;
         }
         else
             return -1;          // no room for pending record
-
-        slen = MeasureGroupToString(_pending, buf, bufsize);
+        // add comma
+        slen = sprintf_s(buf, bufsize, ",");
         if (slen > 0)
         {
             bufsize -= slen;
             buf += slen;
-            lastcomma = buf;
-            _hasPending = false;
-            copydata = true;
         }
         else
-            return -1;          // no room for pending record
+            return -1;
+        lastcomma = buf;
+        _hasPending = false;
+        copydata = true;
     }
     
     while (!MeasureBuf.empty())
@@ -158,41 +221,26 @@
         hasdata = true;
         _hasPending = true;
         
-        if (secs != _pending.Created)
-        {
-            if (settime && lastcomma != NULL)
-            {
-                *(lastcomma - 1) = '}';
-                if (bufsize > 2)
-                {
-                    strcpy(buf, ",{");
-                    buf += 2;
-                    bufsize -= 2;
-                }
-            }
-            secs = _pending.Created;
-            slen = AddTime(secs, buf, bufsize);
-            if (slen > 0)
-            {
-                bufsize -= slen;
-                buf += slen;
-                settime = true;
-            }
-            else
-                break;
-        }
-        
-        slen = MeasureGroupToString(_pending, buf, bufsize);
+        slen = MeasureSnapshotToString(_pending, buf, bufsize);
         if (slen > 0)
         {
             bufsize -= slen;
             buf += slen;
-            lastcomma = buf;
-            _hasPending = false;
-            copydata = true;
         }
         else
             break;              // no room to serialize, leave pending for next message
+        // add comma
+        slen = sprintf_s(buf, bufsize, ",");
+        if (slen > 0)
+        {
+            bufsize -= slen;
+            buf += slen;
+        }
+        else
+            break;
+        _hasPending = false;
+        lastcomma = buf;
+        copydata = true;
     }
     
     if (!hasdata)
@@ -201,11 +249,8 @@
     if (!copydata)
         return -1;              // have data but buffer too small
 
-    // replace final ',' with '}'
-    *(lastcomma - 1) = '}';
-    // this is the extra space we reserved at the start.
-    *(lastcomma) = ']';
-    lastcomma++;
+    // replace final ',' with ']'
+    *(lastcomma - 1) = ']';
     
     return lastcomma - startbuf;
 }
@@ -247,7 +292,3 @@
     return startlen - bufsize;
 }
 
-bool IothubSerial::HasMeasureGroup()
-{
-    return _hasPending;
-}