env: C2_PLUGINDIR now supports multiple paths (: separated)

Author: bvdberg

compiler/main.c2

@@ -504,10 +504,7 @@ fn void Context.handle_args(Context* c, i32 argc, char** argv) {
         }
     } else {
         const char* plugin_dir = getenv("C2_PLUGINDIR");
-        if (plugin_dir) {
-            u32 path_name = c.auxPool.addStr(plugin_dir, true);
-            c.plugins.addPath(path_name);
-        }
+        if (plugin_dir) string_utils.split_paths(plugin_dir, c, on_plugin_dir);
     }
 
     c.comp_opts.libdir = getenv("C2_LIBDIR");
@@ -516,6 +513,12 @@ fn void Context.handle_args(Context* c, i32 argc, char** argv) {
     }
 }
 
+fn void on_plugin_dir(void* arg, const char* path, u32 size) {
+    Context* c = arg;
+    u32 path_idx = c.auxPool.add(path, size, true);
+    c.plugins.addPath(path_idx);
+}
+
 fn void Context.handle_plugins(Context* c) {
     if (c.opts.show_plugins) {
         c.plugins.show();