Houston, we have a trunk.

git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@3122 221aa14e-8319-0410-a670-987f0aec2ac5

1 files changed, 96 insertions, 0 deletions

diff --git a/gr-radar/src/lib/time_series.cc b/gr-radar/src/lib/time_series.cc
new file mode 100644
index 000000000..2767165dc
--- /dev/null
+++ b/gr-radar/src/lib/time_series.cc
@@ -0,0 +1,96 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2005 Free Software Foundation, Inc.
+ * 
+ * This file is part of GNU Radio
+ * 
+ * GNU Radio is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ * 
+ * GNU Radio is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Radio; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "time_series.h"
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <iostream>
+
+
+time_series::time_series(size_t itemsize, const std::string filename,
+			 unsigned long long starting_offset,
+			 long long nsamples_to_process)
+  : d_itemsize(itemsize), d_filename(filename), d_fd(-1), 
+    d_start(starting_offset), d_buffer(0)
+{
+  if ((d_fd = open(d_filename.c_str(), O_RDONLY | O_LARGEFILE, 0660)) == -1){
+    perror(d_filename.c_str());
+    throw std::string("open failed: ") + d_filename;
+  }
+
+  struct stat statbuf;
+  if (fstat(d_fd, &statbuf) == -1){
+    perror(d_filename.c_str());
+    throw std::string("fstat failed: ") + d_filename;
+  }
+  d_filesize = statbuf.st_size;
+  d_limit = d_filesize / d_itemsize;
+
+  if (d_start > d_limit){
+    std::string s = std::string("d_start > filesize: ") + d_filename;
+    std::cerr << s
+	      << " d_start " << d_start
+	      << " d_limit " << d_limit << std::endl;
+    throw s;
+  }
+
+  if (nsamples_to_process > 0)
+    if ((d_start + nsamples_to_process) < d_limit)
+      d_limit = d_start + nsamples_to_process;
+
+  d_buffer = mmap(0, d_filesize, PROT_READ, MAP_SHARED, d_fd, 0);
+  if (d_buffer == MAP_FAILED){
+    perror("mmap");
+    throw std::string("mmap failed: ") + d_filename;
+  }
+}
+
+time_series::~time_series()
+{
+  munmap(d_buffer, d_filesize);
+  close(d_fd);
+}
+
+const void *
+time_series::seek(unsigned long long pos, unsigned long long blocksize) const
+{
+  if ((d_start + pos + blocksize) >= d_limit)
+    return 0;
+
+  return (const void *)((char *)d_buffer + ((d_start + pos) * d_itemsize));
+}
+
+long long
+time_series::nsamples_available(unsigned long long pos) const
+{
+  if ((d_start + pos) >= d_limit)
+    return 0;
+
+  return d_limit - (d_start + pos);
+}