Added mini example program for reading files

1 files changed, 117 insertions, 0 deletions

diff --git a/example/read_example.adb b/example/read_example.adb
new file mode 100644
index 0000000..33b2d7a
--- /dev/null
+++ b/example/read_example.adb
@@ -0,0 +1,117 @@
+
+
+--  Programmed by Jedidiah Barber
+--  Released into the public domain
+
+
+--  This program opens the file supplied as a command line argument, then reads
+--  up to 5 frames from it in Short, Integer, Float, Double formats, seeking to
+--  the file beginning between each read. The data is printed to stdout, then
+--  the file is closed. No modifications are made.
+
+
+with
+
+    Ada.Command_Line,
+    Ada.Directories,
+    Ada.Text_IO,
+    Interfaces,
+    Libsndfile;
+
+
+procedure Read_Example is
+
+
+    package ACom renames Ada.Command_Line;
+    package ADir renames Ada.Directories;
+    package TIO renames Ada.Text_IO;
+
+
+    My_Info : Libsndfile.File_Info := Libsndfile.Blank_Info;
+    My_Sound_File : Libsndfile.Sound_File;
+
+
+begin
+
+
+    if ACom.Argument_Count < 1 then
+        TIO.Put_Line ("No filename provided");
+        ACom.Set_Exit_Status (ACom.Failure);
+        return;
+    end if;
+
+    if not ADir.Exists (ACom.Argument (1)) then
+        TIO.Put_Line ("File does not exist");
+        ACom.Set_Exit_Status (ACom.Failure);
+        return;
+    end if;
+
+
+    TIO.Put_Line ("Load file " & ACom.Argument (1));
+    My_Sound_File.Open (ACom.Argument (1), Libsndfile.Read_Only, My_Info);
+    TIO.New_Line;
+
+    declare
+        Channel_Count : Natural := Libsndfile.Channels (My_Info);
+        Test_Frames   : Libsndfile.Count_Type := 5;
+
+        My_Shorts   : Libsndfile.Short_Data   (1 .. Natural (Test_Frames) * Channel_Count);
+        My_Integers : Libsndfile.Integer_Data (1 .. Natural (Test_Frames) * Channel_Count);
+        My_Floats   : Libsndfile.Float_Data   (1 .. Natural (Test_Frames) * Channel_Count);
+        My_Doubles  : Libsndfile.Double_Data  (1 .. Natural (Test_Frames) * Channel_Count);
+
+        Read_Count, Position : Libsndfile.Count_Type;
+    begin
+        TIO.Put_Line ("Reading" & Libsndfile.Count_Type'Image (Test_Frames) &
+            " frames of Short data");
+        Read_Count := My_Sound_File.Read_Short (My_Shorts, Test_Frames);
+        TIO.Put_Line ("Obtained" & Libsndfile.Count_Type'Image (Read_Count) & " frames");
+        for Index in Integer range 1 .. Natural (Read_Count) * Channel_Count loop
+            TIO.Put_Line (Interfaces.Integer_16'Image (My_Shorts (Index)));
+        end loop;
+        TIO.Put_Line ("Seeking to start again");
+        Position := My_Sound_File.Seek (0, Libsndfile.From_Start);
+        TIO.Put_Line ("Reached position" & Libsndfile.Count_Type'Image (Position));
+        TIO.New_Line;
+
+        TIO.Put_Line ("Reading" & Libsndfile.Count_Type'Image (Test_Frames) &
+            " frames of Integer data");
+        Read_Count := My_Sound_File.Read_Integer (My_Integers, Test_Frames);
+        TIO.Put_Line ("Obtained" & Libsndfile.Count_Type'Image (Read_Count) & " frames");
+        for Index in Integer range 1 .. Natural (Read_Count) * Channel_Count loop
+            TIO.Put_Line (Interfaces.Integer_32'Image (My_Integers (Index)));
+        end loop;
+        TIO.Put_Line ("Seeking to start again");
+        Position := My_Sound_File.Seek (0, Libsndfile.From_Start);
+        TIO.Put_Line ("Reached position" & Libsndfile.Count_Type'Image (Position));
+        TIO.New_Line;
+
+        TIO.Put_Line ("Reading" & Libsndfile.Count_Type'Image (Test_Frames) &
+            " frames of Float data");
+        Read_Count := My_Sound_File.Read_Float (My_Floats, Test_Frames);
+        TIO.Put_Line ("Obtained" & Libsndfile.Count_Type'Image (Read_Count) & " frames");
+        for Index in Integer range 1 .. Natural (Read_Count) * Channel_Count loop
+            TIO.Put_Line (Interfaces.IEEE_Float_32'Image (My_Floats (Index)));
+        end loop;
+        TIO.Put_Line ("Seeking to start again");
+        Position := My_Sound_File.Seek (0, Libsndfile.From_Start);
+        TIO.Put_Line ("Reached position" & Libsndfile.Count_Type'Image (Position));
+        TIO.New_Line;
+
+        TIO.Put_Line ("Reading" & Libsndfile.Count_Type'Image (Test_Frames) &
+            " frames of Double data");
+        Read_Count := My_Sound_File.Read_Double (My_Doubles, Test_Frames);
+        TIO.Put_Line ("Obtained" & Libsndfile.Count_Type'Image (Read_Count) & " frames");
+        for Index in Integer range 1 .. Natural (Read_Count) * Channel_Count loop
+            TIO.Put_Line (Interfaces.IEEE_Float_64'Image (My_Doubles (Index)));
+        end loop;
+        TIO.New_Line;
+    end;
+
+    My_Sound_File.Close;
+    TIO.Put_Line ("File closed");
+
+
+end Read_Example;
+
+