bake package_name into the android module (#11)

- update resources to no longer use WriteFiles and just compile directly
with `aapt2 compile`
- bake package_name into the Zig `android` package so it can always log
with the correct tag name
   - ie. even if SDL starts your code from a new thread

Author: silbinarywolf

build.zig

@@ -22,5 +22,12 @@ pub fn build(b: *std.Build) void {
         .target = target,
         .optimize = optimize,
     });
+
+    // Create stub of builtin options.
+    // This is discovered and then replace in src/androidbuild/apk.zig
+    const android_builtin_options = std.Build.addOptions(b);
+    android_builtin_options.addOption([:0]const u8, "package_name", "");
+    module.addImport("android_builtin", android_builtin_options.createModule());
+
     module.linkSystemLibrary("log", .{});
 }

examples/minimal/README.md

@@ -29,12 +29,17 @@ adb uninstall "com.zig.minimal"
 
 ### View logs of application
 
-Powershell
+Powershell (app doesn't need to be running)
 ```sh
 adb logcat | Select-String com.zig.minimal:
 ```
 
-Bash
+Bash (app doesn't need running to be running)
+```sh
+adb logcat com.zig.minimal:D *:S
+```
+
+Bash (app must be running, logs everything by the process including modules)
 ```sh
 adb logcat --pid=`adb shell pidof -s com.zig.minimal`
 ```

examples/sdl2/README.md

@@ -35,12 +35,17 @@ adb uninstall "com.zig.sdl2"
 
 ### View logs of application
 
-Powershell
+Powershell (app doesn't need to be running)
 ```sh
 adb logcat | Select-String com.zig.sdl2:
 ```
 
-Bash
+Bash (app doesn't need running to be running)
+```sh
+adb logcat com.zig.sdl2:D *:S
+```
+
+Bash (app must be running, logs everything by the process including modules)
 ```sh
 adb logcat --pid=`adb shell pidof -s com.zig.sdl2`
 ```

examples/sdl2/src/sdl-zig-demo.zig

@@ -23,14 +23,15 @@ else
 /// This needs to be exported for Android builds
 export fn SDL_main() callconv(.C) void {
     if (builtin.abi == .android) {
-        android.set_default_tag("com.zig.sdl2");
         _ = std.start.callMain();
     } else {
         @panic("SDL_main should not be called outside of Android builds");
     }
 }
 
 pub fn main() !void {
+    log.debug("started sdl-zig-demo", .{});
+
     if (sdl.SDL_Init(sdl.SDL_INIT_VIDEO) < 0) {
         log.info("Unable to initialize SDL: {s}", .{sdl.SDL_GetError()});
         return error.SDLInitializationFailed;
@@ -69,7 +70,14 @@ pub fn main() !void {
     defer sdl.SDL_DestroyTexture(zig_texture);
 
     var quit = false;
+    var has_run_frame: FrameLog = .none;
     while (!quit) {
+        if (has_run_frame == .one_frame_passed) {
+            // NOTE(jae): 2024-10-03
+            // Allow inspection of logs to see if a frame executed at least once
+            log.debug("has executed one frame", .{});
+            has_run_frame = .logged_one_frame;
+        }
         var event: sdl.SDL_Event = undefined;
         while (sdl.SDL_PollEvent(&event) != 0) {
             switch (event.type) {
@@ -83,7 +91,15 @@ pub fn main() !void {
         _ = sdl.SDL_RenderClear(renderer);
         _ = sdl.SDL_RenderCopy(renderer, zig_texture, null, null);
         sdl.SDL_RenderPresent(renderer);
-
         sdl.SDL_Delay(17);
+        if (has_run_frame == .none) {
+            has_run_frame = .one_frame_passed;
+        }
     }
 }
+
+const FrameLog = enum {
+    none,
+    one_frame_passed,
+    logged_one_frame,
+};

src/android/android.zig

@@ -1,19 +1,19 @@
 const std = @import("std");
 const builtin = @import("builtin");
 
-extern "log" fn __android_log_write(prio: c_int, tag: [*c]const u8, text: [*c]const u8) c_int;
+// TODO(jae): 2024-10-03
+// Consider exposing this in the future
+// pub const builtin = android_builtin;
 
-/// Update the tag used by the Android logger, this will default to your package name unless logging occurs in a seperate
-/// thread.
-///
-/// ie. If using via SDL2, you'll likely want the tag set.
-///
-/// NOTE(jae): 2024-09-22
-/// We should look at moving to making the "tag" default your Android package name by parsing that out of your AndroidManifest.xml
-/// or perhaps even just make it use the "name" of your app
-pub fn set_default_tag(tag: [:0]const u8) void {
-    LogWriter.tag = tag;
-}
+const android_builtin = struct {
+    const ab = @import("android_builtin");
+
+    /// package name extracted from your AndroidManifest.xml file
+    /// ie. "com.zig.sdl2"
+    pub const package_name: [:0]const u8 = ab.package_name;
+};
+
+extern "log" fn __android_log_write(prio: c_int, tag: [*c]const u8, text: [*c]const u8) c_int;
 
 /// Alternate panic implementation that calls __android_log_write so that you can see the logging via "adb logcat"
 pub const panic = Panic.panic;
@@ -50,12 +50,12 @@ pub const Level = enum(u8) {
 /// Alternate log function implementation that calls __android_log_write so that you can see the logging via "adb logcat"
 pub fn logFn(
     comptime message_level: std.log.Level,
-    comptime scope: if (builtin.zig_version.minor != 13)
-        // Support Zig 0.14.0-dev
-        @Type(.enum_literal)
-    else
+    comptime scope: if (builtin.zig_version.major == 0 and builtin.zig_version.minor == 13)
         // Support Zig 0.13.0
-        @Type(.EnumLiteral),
+        @Type(.EnumLiteral)
+    else
+        // Support Zig 0.14.0-dev
+        @Type(.enum_literal),
     comptime format: []const u8,
     args: anytype,
 ) void {
@@ -82,9 +82,17 @@ pub fn logFn(
 
 /// LogWriter was was taken basically as is from: https://github.com/ikskuh/ZigAndroidTemplate
 const LogWriter = struct {
-    /// name of the application / log scope
-    /// if not set, it'll default to the "package" attribute defined in AndroidManifest.xml
-    var tag: [:0]const u8 = &[0:0]u8{};
+    /// Default to the "package" attribute defined in AndroidManifest.xml
+    ///
+    /// If tag isn't set when calling "__android_log_write" then it *usually* defaults to the current
+    /// package name, ie. "com.zig.minimal"
+    ///
+    /// However if running via a seperate thread, then it seems to use that threads
+    /// tag, which means if you log after running code through sdl_main, it won't print
+    /// logs with the package name.
+    ///
+    /// To workaround this, we bake the package name into the Zig binaries.
+    var tag: [:0]const u8 = android_builtin.package_name;
 
     level: Level,