Checkpointing work on CRP & posix tasks.

src/PosixTask.cpp

@@ -0,0 +1,56 @@
+
+#include "PosixTask.h"
+
+
+namespace storagemanager
+{
+
+PosixTask::PosixTask(int _sock, uint _length) : sock(_sock), remainingLength(_length)
+{
+}
+
+PosixTask::~PosixTask()
+{
+    // return the socket
+}
+
+void PosixTask::handleError(int errCode)
+{
+    char buf[80];
+    // TODO: construct and log a message
+    cout << "PosixTask caught an error reading from a socket: " << strerror_r(errCode, buf, 80) << endl;
+}
+
+/* Optimization.  Make this read larger chunks into a buffer & supply data from that when possible. */
+int PosixTask::read(vector<uint8_t> *buf, uint offset, uint length)
+{
+    if (length > remainingLength)
+        length = remainingLength;
+    
+    uint originalSize = buf->size();
+    buf->resize(originalSize + length);
+    
+    uint count = 0;
+    int err;
+    while (count < length)
+    {
+        /* TODO: need a timeout here? */
+        err = ::read(sock, &(*buf)[count + offset], length - count);
+        if (err < 0) {
+            buf->resize(originalSize);
+            handleError(errno);
+            return -1;
+        }
+        else if (err == 0) {
+            buf->resize(originalSize);
+            handleError(0);
+            return -1;
+        }
+        count += err;
+        remainingLength -= err;
+    }
+    return count;
+}
+
+
+}