Android lua module

Currently provides only a lovr.android.getApplicationId(). This returns an Android-specific identifier that doesn't cleanly map to anything specific in other OSes.

CMakeLists.txt

@@ -73,6 +73,8 @@ elseif(ANDROID)
   set(LOVR_USE_LUAJIT OFF) # Until buildvm re-invoke works
   set(LOVR_USE_SSE OFF) # Assume ARM. Technically wrong on Android X86…?
   set(LOVR_BUILD_SHARED ON) # Android has only "activities"
+
+  option(LOVR_ENABLE_ANDROID "Enable the Android module" ON)
 elseif(UNIX)
   if(APPLE)
     set(CMAKE_MACOSX_RPATH 1)
@@ -569,7 +571,7 @@ elseif(EMSCRIPTEN)
   target_sources(lovr PRIVATE src/platform/web.c)
 elseif(ANDROID)
   target_link_libraries(lovr log EGL GLESv3)
-  target_sources(lovr PRIVATE src/platform/android.c)
+  target_sources(lovr PRIVATE src/platform/android.c src/api/android.c)
 elseif(UNIX)
   target_sources(lovr PRIVATE src/platform/linux.c)
 endif()

src/api.h

@@ -8,6 +8,7 @@
 
 // Module loaders
 LOVR_API int luaopen_lovr(lua_State* L);
+LOVR_API int luaopen_lovr_android(lua_State* L);
 LOVR_API int luaopen_lovr_audio(lua_State* L);
 LOVR_API int luaopen_lovr_data(lua_State* L);
 LOVR_API int luaopen_lovr_event(lua_State* L);

src/api/android.c

@@ -0,0 +1,31 @@
+#include "api.h"
+#include "sds.h"
+
+static int l_lovrGetApplicationId(lua_State *L) {
+  pid_t pid = getpid();
+  sds procPath = sdscatfmt(sdsempty(), "/proc/%d/cmdline", (int)pid);
+  FILE *procFile = fopen(procPath, "r");
+  sdsfree(procPath);
+  if (procFile) {
+    sds procData = sdsempty();
+    char data[64];
+    int read;
+    while (read = fread(data, sizeof(data), 1, procFile)) {
+      procData = sdscatlen(procData, data, read);
+    }
+    sdsfree(procData);
+  } else {
+    lua_pushnil(L);
+  }
+  return 1;
+}
+
+static const luaL_Reg lovrAndroid[] = {
+  { "getApplicationId", l_lovrGetApplicationId },
+}
+
+LOVR_API int luaopen_lovr_android(lua_State* L) {
+  lua_newtable(L);
+  luaL_register(L, NULL, lovrAndroid);
+  return 1;
+}

src/api/lovr.c

@@ -6,6 +6,9 @@
 
 const luaL_Reg lovrModules[] = {
   { "lovr", luaopen_lovr },
+#ifdef LOVR_ENABLE_ANDROID
+  { "lovr.android", luaopen_lovr_android },
+#endif
 #ifdef LOVR_ENABLE_AUDIO
   { "lovr.audio", luaopen_lovr_audio },
 #endif

src/resources/boot.lua

@@ -50,6 +50,7 @@ end
 function lovr.boot()
   local conf = {
     modules = {
+      android = true,
       audio = true,
       data = true,
       event = true,