2 files changed, 85 insertions, 26 deletions

diff --git a/gr-blocks/lib/file_source_impl.cc b/gr-blocks/lib/file_source_impl.cc
index 0d20827b7..ed1f50c43 100644
--- a/gr-blocks/lib/file_source_impl.cc
+++ b/gr-blocks/lib/file_source_impl.cc
@@ -54,39 +54,87 @@ namespace gr {
 
     file_source::sptr file_source::make(size_t itemsize, const char *filename, bool repeat)
     {
-      return gnuradio::get_initial_sptr(new file_source_impl(itemsize, filename, repeat));
+      return gnuradio::get_initial_sptr
+	(new file_source_impl(itemsize, filename, repeat));
     }
 
     file_source_impl::file_source_impl(size_t itemsize, const char *filename, bool repeat)
       : gr_sync_block("file_source",
 		      gr_make_io_signature(0, 0, 0),
 		      gr_make_io_signature(1, 1, itemsize)),
-	d_itemsize(itemsize), d_fp (0), d_repeat(repeat)
+	d_itemsize(itemsize), d_fp(0), d_new_fp(0), d_repeat(repeat),
+	d_updated(false)
     {
-      // we use "open" to use to the O_LARGEFILE flag
+      open(filename, repeat);
+    }
+
+    file_source_impl::~file_source_impl()
+    {
+      fclose ((FILE*)d_fp);
+    }
+    
+    bool
+    file_source_impl::seek(long seek_point, int whence)
+    {
+      return fseek((FILE*)d_fp, seek_point *d_itemsize, whence) == 0;
+    }
+
+
+    void
+    file_source_impl::open(const char *filename, bool repeat)
+    {
+      // obtain exclusive access for duration of this function
+      boost::mutex::scoped_lock lock(fp_mutex);
 
       int fd;
 
-      if ((fd = open (filename, O_RDONLY | OUR_O_LARGEFILE | OUR_O_BINARY)) < 0){
-	perror (filename);
-	throw std::runtime_error ("can't open file");
+      // we use "open" to use to the O_LARGEFILE flag
+      if((fd = ::open(filename, O_RDONLY | OUR_O_LARGEFILE | OUR_O_BINARY)) < 0) {
+	perror(filename);
+	throw std::runtime_error("can't open file");
+      }
+
+      if(d_new_fp) {
+	fclose(d_new_fp);
+	d_new_fp = 0;
       }
 
-      if ((d_fp = fdopen (fd, "rb")) == NULL) {
+      if((d_new_fp = fdopen (fd, "rb")) == NULL) {
 	perror(filename);
+	::close(fd);	// don't leak file descriptor if fdopen fails
 	throw std::runtime_error("can't open file");
       }
+
+      d_updated = true;
+      d_repeat = repeat;
     }
 
-    file_source_impl::~file_source_impl()
+    void
+    file_source_impl::close()
     {
-      fclose ((FILE *) d_fp);
+      // obtain exclusive access for duration of this function
+      boost::mutex::scoped_lock lock(fp_mutex);
+
+      if(d_new_fp != NULL) {
+	fclose(d_new_fp);
+	d_new_fp = NULL;
+      }
+      d_updated = true;
     }
-    
-    bool
-    file_source_impl::seek(long seek_point, int whence)
+
+    void
+    file_source_impl::do_update()
     {
-      return fseek ((FILE *) d_fp, seek_point *d_itemsize, whence) == 0;
+      if(d_updated) {
+	boost::mutex::scoped_lock lock(fp_mutex); // hold while in scope
+
+	if(d_fp)
+	  fclose(d_fp);
+
+	d_fp = d_new_fp;    // install new file pointer
+	d_new_fp = 0;
+	d_updated = false;
+      }
     }
 
     int
@@ -94,37 +142,41 @@ namespace gr {
 			   gr_vector_const_void_star &input_items,
 			   gr_vector_void_star &output_items)
     {
-      char *o = (char *) output_items[0];
+      char *o = (char*)output_items[0];
       int i;
       int size = noutput_items;
 
-      while (size) {
-	i = fread(o, d_itemsize, size, (FILE *) d_fp);
+      do_update();       // update d_fp is reqd
+      if(d_fp == NULL)
+	throw std::runtime_error("work with file not open");
+
+      boost::mutex::scoped_lock lock(fp_mutex); // hold for the rest of this function
+      while(size) {
+	i = fread(o, d_itemsize, size, (FILE*)d_fp);
 
 	size -= i;
 	o += i * d_itemsize;
 
-	if (size == 0)		// done
+	if(size == 0)		// done
 	  break;
 
-	if (i > 0)			// short read, try again
+	if(i > 0)			// short read, try again
 	  continue;
 
 	// We got a zero from fread.  This is either EOF or error.  In
 	// any event, if we're in repeat mode, seek back to the beginning
 	// of the file and try again, else break
-	
-	if (!d_repeat)
+	if(!d_repeat)
 	  break;
 
-	if (fseek ((FILE *) d_fp, 0, SEEK_SET) == -1) {
+	if(fseek ((FILE *) d_fp, 0, SEEK_SET) == -1) {
 	  fprintf(stderr, "[%s] fseek failed\n", __FILE__);
 	  exit(-1);
 	}
       }
 
-      if (size > 0) {	     		// EOF or error
-	if (size == noutput_items)      // we didn't read anything; say we're done
+      if(size > 0) {	     		// EOF or error
+	if(size == noutput_items)       // we didn't read anything; say we're done
 	  return -1;
 	return noutput_items - size;	// else return partial result
       }
diff --git a/gr-blocks/lib/file_source_impl.h b/gr-blocks/lib/file_source_impl.h
index c35d563d1..600fe80ab 100644
--- a/gr-blocks/lib/file_source_impl.h
+++ b/gr-blocks/lib/file_source_impl.h
@@ -31,15 +31,22 @@ namespace gr {
     class BLOCKS_API file_source_impl : public file_source
     {
     private:
-      size_t  d_itemsize;
-      void   *d_fp;
-      bool    d_repeat;
+      size_t d_itemsize;
+      FILE *d_fp;
+      FILE *d_new_fp;
+      bool d_repeat;
+      bool d_updated;
+      boost::mutex fp_mutex;
       
+      void do_update();
+
     public:
       file_source_impl(size_t itemsize, const char *filename, bool repeat);
       ~file_source_impl();
 
       bool seek(long seek_point, int whence);
+      void open(const char *filename, bool repeat);
+      void close();
 
       int work(int noutput_items,
 	       gr_vector_const_void_star &input_items,