From 0ba2c5ffcc5ca89a6565572de34bc1c0cf2492b9 Mon Sep 17 00:00:00 2001
From: Luna <git@l4.pm>
Date: Tue, 2 Jun 2020 21:42:26 -0300
Subject: [PATCH] add basics of searching for lilv

---
 build.zig | 25 ++++++++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

diff --git a/build.zig b/build.zig
index 622961e..da24ddb 100644
--- a/build.zig
+++ b/build.zig
@@ -1,5 +1,6 @@
-const builds = @import("std").build;
-const Builder = @import("std").build.Builder;
+const std = @import("std");
+const builds = std.build;
+const Builder = std.build.Builder;
 
 fn setupLinks(step: *builds.LibExeObjStep) void {
     step.linkSystemLibrary("c");
@@ -11,8 +12,26 @@ fn setupLinks(step: *builds.LibExeObjStep) void {
     step.linkSystemLibrary("GraphicsMagickWand");
     step.linkSystemLibrary("GraphicsMagick");
 
-    step.addIncludeDir("/usr/include/lilv-0");
     step.addIncludeDir("/usr/include/GraphicsMagick");
+
+    const possible_lilv_include_dirs = [_][]const u8{
+        "/usr/include/lilv-0",
+        "/usr/include/lilv-0/lilv",
+    };
+    var found_any_lilv = false;
+
+    for (possible_lilv_include_dirs) |possible_lilv_dir| {
+        var possible_dir = std.fs.cwd().openDir(possible_lilv_dir) catch |err| {
+            continue;
+        };
+        possible_dir.close();
+        found_any_lilv = true;
+    }
+
+    if (!found_any_lilv) {
+        std.debug.warn("No LILV library was found :(\n");
+        @panic("no lilv found");
+    }
 }
 
 pub fn build(b: *Builder) void {