[Cherry-pick] Clean up EGL Loader.

Removes deprecated driver loading path, clean up comments and misc.

Bug: b/293503000
Test: boot
Change-Id: Ibc62bf59ed7b0cb3671583d2af853c457977d1d1
Merged-In: Ibc62bf59ed7b0cb3671583d2af853c457977d1d1
diff --git a/opengl/libs/EGL/Loader.cpp b/opengl/libs/EGL/Loader.cpp
index 654e5b7..04e2fff 100644
--- a/opengl/libs/EGL/Loader.cpp
+++ b/opengl/libs/EGL/Loader.cpp
@@ -41,24 +41,44 @@
 /*
  * EGL userspace drivers must be provided either:
  * - as a single library:
- *      /vendor/lib/egl/libGLES.so
+ *      /vendor/${LIB}/egl/libGLES.so
  *
  * - as separate libraries:
- *      /vendor/lib/egl/libEGL.so
- *      /vendor/lib/egl/libGLESv1_CM.so
- *      /vendor/lib/egl/libGLESv2.so
+ *      /vendor/${LIB}/egl/libEGL.so
+ *      /vendor/${LIB}/egl/libGLESv1_CM.so
+ *      /vendor/${LIB}/egl/libGLESv2.so
  *
  * For backward compatibility and to facilitate the transition to
  * this new naming scheme, the loader will additionally look for:
  *
- *      /{vendor|system}/lib/egl/lib{GLES | [EGL|GLESv1_CM|GLESv2]}_*.so
+ *      /vendor/${LIB}/egl/lib{GLES | [EGL|GLESv1_CM|GLESv2]}_${SUFFIX}.so
  *
  */
 
-Loader& Loader::getInstance() {
-    static Loader loader;
-    return loader;
-}
+#ifndef SYSTEM_LIB_PATH
+#if defined(__LP64__)
+#define SYSTEM_LIB_PATH "/system/lib64"
+#else
+#define SYSTEM_LIB_PATH "/system/lib"
+#endif
+#endif
+
+static const char* PERSIST_DRIVER_SUFFIX_PROPERTY = "persist.graphics.egl";
+static const char* RO_DRIVER_SUFFIX_PROPERTY = "ro.hardware.egl";
+static const char* RO_BOARD_PLATFORM_PROPERTY = "ro.board.platform";
+
+static const char* HAL_SUBNAME_KEY_PROPERTIES[3] = {
+        PERSIST_DRIVER_SUFFIX_PROPERTY,
+        RO_DRIVER_SUFFIX_PROPERTY,
+        RO_BOARD_PLATFORM_PROPERTY,
+};
+
+static const char* const VENDOR_LIB_EGL_DIR =
+#if defined(__LP64__)
+        "/vendor/lib64/egl";
+#else
+        "/vendor/lib/egl";
+#endif
 
 static void* do_dlopen(const char* path, int mode) {
     ATRACE_CALL();
@@ -80,6 +100,17 @@
     return android_unload_sphal_library(dso);
 }
 
+static void* load_wrapper(const char* path) {
+    void* so = do_dlopen(path, RTLD_NOW | RTLD_LOCAL);
+    ALOGE_IF(!so, "dlopen(\"%s\") failed: %s", path, dlerror());
+    return so;
+}
+
+Loader& Loader::getInstance() {
+    static Loader loader;
+    return loader;
+}
+
 Loader::driver_t::driver_t(void* gles)
 {
     dso[0] = gles;
@@ -123,30 +154,6 @@
 Loader::~Loader() {
 }
 
-static void* load_wrapper(const char* path) {
-    void* so = do_dlopen(path, RTLD_NOW | RTLD_LOCAL);
-    ALOGE_IF(!so, "dlopen(\"%s\") failed: %s", path, dlerror());
-    return so;
-}
-
-#ifndef EGL_WRAPPER_DIR
-#if defined(__LP64__)
-#define EGL_WRAPPER_DIR "/system/lib64"
-#else
-#define EGL_WRAPPER_DIR "/system/lib"
-#endif
-#endif
-
-static const char* PERSIST_DRIVER_SUFFIX_PROPERTY = "persist.graphics.egl";
-static const char* RO_DRIVER_SUFFIX_PROPERTY = "ro.hardware.egl";
-static const char* RO_BOARD_PLATFORM_PROPERTY = "ro.board.platform";
-
-static const char* HAL_SUBNAME_KEY_PROPERTIES[3] = {
-        PERSIST_DRIVER_SUFFIX_PROPERTY,
-        RO_DRIVER_SUFFIX_PROPERTY,
-        RO_BOARD_PLATFORM_PROPERTY,
-};
-
 // Check whether the loaded system drivers should be unloaded in order to
 // load ANGLE or the updatable graphics drivers.
 // If ANGLE namespace is set, it means the application is identified to run on top of ANGLE.
@@ -323,13 +330,13 @@
                         HAL_SUBNAME_KEY_PROPERTIES[2]);
 
     if (!cnx->libEgl) {
-        cnx->libEgl = load_wrapper(EGL_WRAPPER_DIR "/libEGL.so");
+        cnx->libEgl = load_wrapper(SYSTEM_LIB_PATH "/libEGL.so");
     }
     if (!cnx->libGles1) {
-        cnx->libGles1 = load_wrapper(EGL_WRAPPER_DIR "/libGLESv1_CM.so");
+        cnx->libGles1 = load_wrapper(SYSTEM_LIB_PATH "/libGLESv1_CM.so");
     }
     if (!cnx->libGles2) {
-        cnx->libGles2 = load_wrapper(EGL_WRAPPER_DIR "/libGLESv2.so");
+        cnx->libGles2 = load_wrapper(SYSTEM_LIB_PATH "/libGLESv2.so");
     }
 
     if (!cnx->libEgl || !cnx->libGles2 || !cnx->libGles1) {
@@ -432,31 +439,19 @@
     class MatchFile {
     public:
         static std::string find(const char* libraryName, const bool exact) {
-            const char* const searchPaths[] = {
-#if defined(__LP64__)
-                    "/vendor/lib64/egl",
-                    "/system/lib64/egl"
-#else
-                    "/vendor/lib/egl",
-                    "/system/lib/egl"
-#endif
-            };
-
-            for (auto dir : searchPaths) {
-                std::string absolutePath;
-                if (find(absolutePath, libraryName, dir, exact)) {
-                    return absolutePath;
-                }
+            std::string absolutePath;
+            if (findLibPath(absolutePath, libraryName, exact)) {
+                return absolutePath;
             }
 
             // Driver not found. gah.
             return std::string();
         }
     private:
-        static bool find(std::string& result,
-                const std::string& pattern, const char* const search, bool exact) {
+        static bool findLibPath(std::string& result, const std::string& pattern, bool exact) {
+            const std::string vendorLibEglDirString = std::string(VENDOR_LIB_EGL_DIR);
             if (exact) {
-                std::string absolutePath = std::string(search) + "/" + pattern + ".so";
+                std::string absolutePath = vendorLibEglDirString + "/" + pattern + ".so";
                 if (!access(absolutePath.c_str(), R_OK)) {
                     result = absolutePath;
                     return true;
@@ -464,7 +459,7 @@
                 return false;
             }
 
-            DIR* d = opendir(search);
+            DIR* d = opendir(VENDOR_LIB_EGL_DIR);
             if (d != nullptr) {
                 struct dirent* e;
                 while ((e = readdir(d)) != nullptr) {
@@ -477,7 +472,7 @@
                     }
                     if (strstr(e->d_name, pattern.c_str()) == e->d_name) {
                         if (!strcmp(e->d_name + strlen(e->d_name) - 3, ".so")) {
-                            result = std::string(search) + "/" + e->d_name;
+                            result = vendorLibEglDirString + "/" + e->d_name;
                             closedir(d);
                             return true;
                         }