[rygel] engine: Add large files (> 4GB) streaming support.

[Jens Georg <jensgeorg src gnome org>]

commit 4b915419791115bfbd63d79d2b59701550d86ec1
Author: Jean-Baptiste Dubois <jean-baptiste dubois parrot com>
Date:   Mon Oct 7 09:49:01 2013 +0200

    engine: Add large files (> 4GB) streaming support.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=709551

 configure.ac                                       |    2 +
 src/media-engines/simple/Makefile.am               |    1 +
 .../simple/rygel-simple-data-source.vala           |   43 +++++++++++++++-----
 3 files changed, 36 insertions(+), 10 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 3e4982e..a460a80 100644
--- a/configure.ac
+++ b/configure.ac
@@ -27,6 +27,8 @@ dnl Disable generation of static libraries
 LT_PREREQ([2.2.6])
 LT_INIT([dlopen disable-static])
 
+AC_SYS_LARGEFILE
+
 dnl Required versions of library packages
 dnl Not all of these are actually used, depending on the configure options.
 GLIB_REQUIRED=2.31.13
diff --git a/src/media-engines/simple/Makefile.am b/src/media-engines/simple/Makefile.am
index 3a6aa8e..67b3dfb 100644
--- a/src/media-engines/simple/Makefile.am
+++ b/src/media-engines/simple/Makefile.am
@@ -8,6 +8,7 @@ librygel_media_engine_simple_la_SOURCES = \
        rygel-simple-data-source.vala
 
 librygel_media_engine_simple_la_VALAFLAGS = \
+       --pkg posix \
        $(RYGEL_COMMON_LIBRYGEL_SERVER_VALAFLAGS) \
        $(RYGEL_COMMON_VALAFLAGS)
 
diff --git a/src/media-engines/simple/rygel-simple-data-source.vala 
b/src/media-engines/simple/rygel-simple-data-source.vala
index d0ccbd4..3f66941 100644
--- a/src/media-engines/simple/rygel-simple-data-source.vala
+++ b/src/media-engines/simple/rygel-simple-data-source.vala
@@ -34,8 +34,8 @@ internal class Rygel.SimpleDataSource : DataSource, Object {
     private Thread<void*> thread;
     private Mutex mutex = Mutex ();
     private Cond cond = Cond ();
-    private uint64 first_byte = 0;
-    private uint64 last_byte = 0;
+    private Posix.off_t first_byte = 0;
+    private Posix.off_t last_byte = 0;
     private bool frozen = false;
     private bool stop_thread = false;
     private HTTPSeek offsets = null;
@@ -103,13 +103,26 @@ internal class Rygel.SimpleDataSource : DataSource, Object {
     private void* thread_func () {
         var file = File.new_for_commandline_arg (this.uri);
         debug ("Spawning new thread for streaming file %s", this.uri);
+        int fd = -1;
         try {
-            var mapped = new MappedFile (file.get_path (), false);
+            fd = Posix.open (file.get_path (), Posix.O_RDONLY, 0);
+            if (fd < 0) {
+                throw new IOError.FAILED ("Failed to open file '%s': %s",
+                                          file.get_path (),
+                                          Posix.strerror (Posix.errno));
+            }
+
             if (this.offsets != null) {
-                this.first_byte = this.offsets.start;
-                this.last_byte = this.offsets.stop + 1;
+                this.first_byte = (Posix.off_t) this.offsets.start;
+                this.last_byte = (Posix.off_t) this.offsets.stop + 1;
             } else {
-                this.last_byte = mapped.get_length ();
+                this.first_byte = 0;
+                this.last_byte = Posix.lseek (fd, 0, Posix.SEEK_END);
+                Posix.lseek (fd, 0, Posix.SEEK_SET);
+            }
+
+            if (this.first_byte != 0) {
+                 Posix.lseek (fd, this.first_byte, Posix.SEEK_SET);
             }
 
             while (true) {
@@ -134,9 +147,15 @@ internal class Rygel.SimpleDataSource : DataSource, Object {
                     stop = this.last_byte;
                 }
 
-                unowned uint8[] data = (uint8[]) mapped.get_contents ();
-                data.length = (int) mapped.get_length ();
-                uint8[] slice = data[start:stop];
+                var slice = new uint8[stop - start];
+                var len = (int) Posix.read (fd, slice, slice.length);
+                if (len < 0) {
+                    throw new IOError.FAILED ("Failed to read file '%s': %s",
+                                              file.get_path (),
+                                              Posix.strerror (Posix.errno));
+                }
+
+                slice.length = len;
                 this.first_byte = stop;
 
                 // There's a potential race condition here.
@@ -149,7 +168,11 @@ internal class Rygel.SimpleDataSource : DataSource, Object {
                 });
             }
         } catch (Error error) {
-            warning ("Failed to map file: %s", error.message);
+            warning ("Failed to stream file %s: %s",
+                     file.get_path (),
+                     error.message);
+        } finally {
+            Posix.close (fd);
         }
 
         // Signal that we're done streaming