Fix platform detection

Get rid of sys/utsname.h reference, it's not available on mingw32.

configure.ac

@@ -4,6 +4,13 @@ AC_INIT([spek], [0.5])
 AC_CONFIG_SRCDIR([src/spek.vala])
 AC_CONFIG_HEADERS([config.h])
 
+# Determine the system type.
+AC_CANONICAL_HOST
+AC_SUBST(host_os)
+AC_DEFINE_UNQUOTED(HOST_OS, "$host_os",
+  [Define the canonical host OS type.]
+)
+
 AM_INIT_AUTOMAKE([no-dist-gzip dist-bzip2])
 
 # Enable silent rules is available

src/Makefile.am

@@ -9,7 +9,6 @@ spek_SOURCES = \
 
 INCLUDES = \
 	-include config.h \
-	-include sys/utsname.h \
 	$(SPEK_CFLAGS) \
 	$(IGE_MAC_CFLAGS) \
 	-DLOCALEDIR=\""$(localedir)"\" \
@@ -17,8 +16,7 @@ INCLUDES = \
 	-DPKGLIBDIR=\""$(pkglibdir)"\"
 
 VALAFLAGS = \
-	--vapidir=$(srcdir)/../vapi
-	--pkg config --pkg sys \
+	--vapidir=$(srcdir)/../vapi --pkg config \
 	@SPEK_PACKAGES@
 
 spek_LDADD = \

src/spek-spectrogram.vala

@@ -20,7 +20,6 @@ using Cairo;
 using Gdk;
 using Gtk;
 using Pango;
-using Sys;
 
 namespace Spek {
 	class Spectrogram : DrawingArea {
@@ -41,13 +40,13 @@ namespace Spek {
 		private const int BPAD = 40;
 		private const int GAP = 10;
 		private const int RULER = 10;
-		private double FONT_SCALE;
+		private double FONT_SCALE = 1.0;
 
 		public Spectrogram () {
 			// Pango/Quartz fonts are smaller than on X.
-			var name = UtsName ();
-			uname (ref name);
-			FONT_SCALE = name.sysname == "Darwin" ? 1.5 : 1.0;
+			if (Config.HOST_OS.down ().has_prefix ("darwin")) {
+				FONT_SCALE = 1.4;
+			}
 
 			// Pre-draw the palette.
 			palette = new ImageSurface (Format.RGB24, RULER, BANDS);

vapi/Makefile.am

@@ -1,6 +1,5 @@
 noinst_DATA = \
-	config.vapi \
-	sys.vapi
+	config.vapi
 
 EXTRA_DIST = \
 	$(noinst_DATA)

vapi/config.vapi

@@ -13,4 +13,7 @@ namespace Config {
 	public const string LOCALEDIR;  /* /usr/local/share/locale  */
 	public const string PKGDATADIR; /* /usr/local/share/spek */
 	public const string PKGLIBDIR;  /* /usr/local/lib/spek   */
+
+	/* linux*, mingw*, or darwin* */
+	public const string HOST_OS;
 }

vapi/sys.vapi

@@ -1,14 +0,0 @@
-[CCode (cheader_filename = "sys/utsname.h")]
-namespace Sys {
-	[CCode (cname = "struct utsname")]
-	public struct UtsName {
-		public weak string sysname;
-		public weak string nodename;
-		public weak string release;
-		public weak string version;
-		public weak string machine;
-		public weak string domainname;
-	}
-	[CCode (cname = "uname")]
-	public int uname (ref UtsName name);
-}