fix cimport not doing deref

src/main.zig

@@ -53,6 +53,30 @@ const Param = struct {
     value: f32,
 };
 
+pub fn lilv_instance_connect_port(
+    instance: [*c]c.LilvInstance,
+    port_index: u32,
+    data_location: ?*c_void,
+) void {
+    instance.?.*.lv2_descriptor.?.*.connect_port.?(instance.?.*.lv2_handle, port_index, data_location);
+}
+
+pub fn lilv_instance_activate(instance: [*c]c.LilvInstance) void {
+    if (instance.?.*.lv2_descriptor.?.*.activate != null) {
+        instance.?.*.lv2_descriptor.?.*.activate.?(instance.?.*.lv2_handle);
+    }
+}
+
+pub fn lilv_instance_run(instance: [*c]c.LilvInstance, sample_count: u32) void {
+    instance.?.*.lv2_descriptor.?.*.run.?(instance.?.*.lv2_handle, sample_count);
+}
+
+pub fn lilv_instance_deactivate(instance: [*c]c.LilvInstance) void {
+    if (instance.?.*.lv2_descriptor.?.*.deactivate != null) {
+        instance.?.*.lv2_descriptor.?.*.deactivate.?(instance.?.*.lv2_handle);
+    }
+}
+
 const ParamList = std.ArrayList(Param);
 
 const PortType = enum {
@@ -74,14 +98,15 @@ const Port = struct {
 const LV2Apply = struct {
     allocator: *std.mem.Allocator,
 
-    world: *c.LilvWorld = undefined,
+    world: ?*c.LilvWorld = null,
-    plugin: *const c.LilvPlugin = undefined,
+    plugin: ?*const c.LilvPlugin = null,
-    instance: *c.LilvInstance = undefined,
+    instance: ?*c.LilvInstance = null,
-    in_path: []u8 = undefined,
-    out_path: []u8 = undefined,
 
-    in_file: *c.SNDFILE = undefined,
+    in_path: ?[]u8 = undefined,
-    out_file: *c.SNDFILE = undefined,
+    out_path: ?[]u8 = undefined,
+
+    in_file: ?*c.SNDFILE = null,
+    out_file: ?*c.SNDFILE = null,
 
     n_params: u32,
 
@@ -96,8 +121,12 @@ const LV2Apply = struct {
         sclose(self.in_path, self.in_file);
         sclose(self.out_path, self.out_file);
 
-        c.lilv_instance_free(self.instance);
+        if (self.instance) |instance| {
-        c.lilv_world_free(self.world);
+            c.lilv_instance_free(self.instance);
+        }
+        if (self.world) |world| {
+            c.lilv_world_free(self.world);
+        }
 
         self.allocator.free(self.ports);
         self.params.deinit();
@@ -172,7 +201,10 @@ const LV2Apply = struct {
     }
 };
 
-fn sopen(path: []const u8, mode: i32, fmt: *c.SF_INFO) ?*c.SNDFILE {
+fn sopen(path_opt: ?[]const u8, mode: i32, fmt: *c.SF_INFO) ?*c.SNDFILE {
+    if (path_opt == null) return null;
+
+    var path = path_opt.?;
     var file = c.sf_open(path.ptr, mode, fmt);
     const st: i32 = c.sf_error(file);
 
@@ -184,7 +216,12 @@ fn sopen(path: []const u8, mode: i32, fmt: *c.SF_INFO) ?*c.SNDFILE {
     return file;
 }
 
-fn sclose(path: []const u8, file: *c.SNDFILE) void {
+fn sclose(path_opt: ?[]const u8, file_opt: ?*c.SNDFILE) void {
+    if (path_opt == null) return;
+    if (file_opt == null) return;
+    var path = path_opt.?;
+    var file = file_opt.?;
+
     var st: i32 = c.sf_close(file);
     if (st != 0) {
         std.debug.warn(
@@ -198,7 +235,9 @@ fn sclose(path: []const u8, file: *c.SNDFILE) void {
 ///Read a single frame from a file into an interleaved buffer.
 ///If more channels are required than are available in the file, the remaining
 ///channels are distributed in a round-robin fashion (LRLRL).
-fn sread(file: *c.SNDFILE, file_chans: c_int, buf: []f32) bool {
+fn sread(file_opt: ?*c.SNDFILE, file_chans: c_int, buf: []f32) bool {
+    var file = file_opt.?;
+
     const n_read: c.sf_count_t = c.sf_readf_float(file, buf.ptr, 1);
     const buf_chans = @intCast(c_int, buf.len);
 
@@ -221,17 +260,14 @@ fn print_version() !void {
 fn print_usage() !void {
     const stdout_file = try std.io.getStdOut();
     try stdout_file.write("Usage: lv2apply [OPTION]... PLUGIN_URI\n");
-    try stdout_file.write(" -i IN_FILE Input file\n");
+    try stdout_file.write("\t-i IN_FILE Input file\n");
-    try stdout_file.write(" -o OUT_FILE Output file\n");
+    try stdout_file.write("\t-o OUT_FILE Output file\n");
-    try stdout_file.write(" -o OUT_FILE Output file\n");
+    try stdout_file.write("\t-c SYM VAL Control value\n");
-    try stdout_file.write("-c SYM VAL Control value\n");
+    try stdout_file.write("\t--help print help\n");
-    try stdout_file.write("--help print help\n");
+    try stdout_file.write("\t--version display version\n");
-    try stdout_file.write("--version display version\n");
 }
 
 pub fn main() !void {
-    std.debug.warn("awoo.\n");
-
     var arena = std.heap.ArenaAllocator.init(std.heap.c_allocator);
     const allocator = &arena.allocator;
 
@@ -388,17 +424,17 @@ pub fn main() !void {
         var p = @intCast(u32, p_idx);
 
         if (ptype == .Control) {
-            c.lilv_instance_connect_port(self.instance, p, &port.value);
+            lilv_instance_connect_port(self.instance, p, &port.value);
         } else if (ptype == .Audio) {
             if (port.is_input) {
-                c.lilv_instance_connect_port(self.instance, p, &in_buf[i]);
+                lilv_instance_connect_port(self.instance, p, &in_buf[i]);
                 i += 1;
             } else {
-                c.lilv_instance_connect_port(self.instance, p, &in_buf[o]);
+                lilv_instance_connect_port(self.instance, p, &in_buf[o]);
                 o += 1;
             }
         } else {
-            c.lilv_instance_connect_port(self.instance, p, null);
+            lilv_instance_connect_port(self.instance, p, null);
         }
     }
 
@@ -407,7 +443,7 @@ pub fn main() !void {
     // read/write from/to sndfile.
     std.debug.warn("almost there!\n");
 
-    c.lilv_instance_activate(self.instance);
+    lilv_instance_activate(self.instance);
 
     const START = 2 * 44100;
     // for the first START frames, copy from in to out
@@ -423,13 +459,13 @@ pub fn main() !void {
     std.debug.warn("{} seeked frames\n", seeked);
 
     while (sread(self.in_file, in_fmt.channels, in_buf)) {
-        c.lilv_instance_run(self.instance, 1);
+        lilv_instance_run(self.instance, 1);
         if (c.sf_writef_float(self.out_file, out_buf.ptr, 1) != 1) {
             std.debug.warn("failed to write to output file\n");
             return;
         }
     }
 
-    c.lilv_instance_deactivate(self.instance);
+    lilv_instance_deactivate(self.instance);
     return;
 }