1 files changed, 152 insertions, 0 deletions
diff --git a/src/Fifo.cpp b/src/Fifo.cpp
new file mode 100644
index 0000000..c5f0853
--- /dev/null
+++ b/src/Fifo.cpp
@@ -0,0 +1,152 @@
+#include <stdio.h>
+#include "Fifo.h"
+
+Fifo::Fifo ()
+{
+  astate = 0;			// not allocated
+  buffer = NULL;
+  totsize = 0;
+  datasize = 0;
+  start = 0;
+  pthread_mutex_init (&mut, 0);
+}
+
+Fifo::Fifo (unsigned int size)
+{
+  buffer = new char[size];
+  if (buffer != NULL)
+    {
+      astate = 1;
+      totsize = size;
+      datasize = 0;
+      start = 0;
+    }
+  else
+    {
+      astate = 0;
+      totsize = 0;
+      datasize = 0;
+      start = 0;
+    }
+  pthread_mutex_init (&mut, 0);
+}
+
+Fifo::~Fifo ()
+{
+  pthread_mutex_lock (&mut);
+  if (astate)
+    delete buffer;
+  pthread_mutex_unlock (&mut);
+}
+
+void
+Fifo::Flush ()
+{
+  pthread_mutex_lock (&mut);
+  astate = 1;
+  //totsize = size;
+  datasize = 0;
+  start = 0;
+  pthread_mutex_unlock (&mut);
+  //for (int x =0; x < sizeof(buffer); x++) {
+  //  buffer[x] = 0;
+  //}
+}
+
+int
+Fifo::ReAlloc (unsigned int size)
+{
+  pthread_mutex_lock (&mut);
+  if (astate)
+    delete buffer;
+  buffer = new char[size];
+  if (buffer != NULL)
+    {
+      astate = 1;
+      totsize = size;
+      datasize = 0;
+      start = 0;
+      pthread_mutex_unlock (&mut);
+    }
+  else
+    {
+      astate = 0;
+      totsize = 0;
+      datasize = 0;
+      start = 0;
+      pthread_mutex_unlock (&mut);
+      return -1;
+    }
+  return 0;
+}
+
+void *
+Fifo::Read (void *buf, unsigned int &len)
+{
+  pthread_mutex_lock (&mut);
+  if (len > datasize)
+    len = datasize;
+  unsigned int rest;
+  if (len > (totsize - start))
+    rest = len - (totsize - start);
+  else
+    rest = 0;
+  unsigned int first = len - rest;
+  memcpy (buf, buffer + start, first);
+  memcpy ((char *) buf + first, buffer, rest);
+  datasize -= len;
+  start += len;
+  if (start >= totsize)
+    start = rest;
+  //if (datasize == 0) printf("in fifo READ, data is zero\n");
+  pthread_mutex_unlock (&mut);
+  return buf;
+}
+
+int
+Fifo::Write (void *buf, unsigned int len)
+{
+  pthread_mutex_lock (&mut);
+  unsigned int end;
+  end = start + datasize;
+  if (end > totsize)
+    end = end - totsize;
+  if (len > (totsize - datasize))
+    {
+      pthread_mutex_unlock (&mut);
+      return -1;
+    }
+  unsigned int rest;
+  if ((len + end) > totsize)
+    rest = (len + end) - totsize;
+  else
+    rest = 0;
+  unsigned int first = len - rest;
+  memcpy (buffer + end, buf, first);
+  memcpy (buffer, (char *) buf + first, rest);
+
+  datasize += len;
+  //if (datasize == 0) printf("in fifo WRITE, data is zero\n");
+  pthread_mutex_unlock (&mut);
+  return len;
+}
+
+unsigned int
+Fifo::FreeSpace (void)
+{				// do we need locks here?
+  int x;
+  pthread_mutex_lock (&mut);
+  x = totsize - datasize;
+  pthread_mutex_unlock (&mut);
+  return x;
+}
+
+unsigned int
+Fifo::UsedSpace (void)
+{
+  int x;
+  pthread_mutex_lock (&mut);
+  x = datasize;
+  pthread_mutex_unlock (&mut);
+  return x;
+}