Fix bugs with fence sync API on iOS devices

- Actually request extension version of fence sync functions
- Fix incorrect usage of dlopen/dlsym
- Also fixed same bugs in Mac code, although we never hit that
  code path.

Should fix iOS devices, giving more accurate (and less spammy)
results from nanobench.

Bug: skia:
Change-Id: I3456b301ef9b0b6559160d1d21c77bd93139d39a
Reviewed-on: https://skia-review.googlesource.com/57740
Reviewed-by: Brian Salomon <[email protected]>
Commit-Queue: Brian Osman <[email protected]>

tools/gpu/gl/GLTestContext.cpp

@@ -67,9 +67,9 @@ std::unique_ptr<GLFenceSync> GLFenceSync::MakeIfSupported(const sk_gpu_test::GLT
 }
 
 GLFenceSync::GLFenceSync(const sk_gpu_test::GLTestContext* ctx, const char* ext) {
-    ctx->getGLProcAddress(&fGLFenceSync, "glFenceSync");
-    ctx->getGLProcAddress(&fGLClientWaitSync, "glClientWaitSync");
-    ctx->getGLProcAddress(&fGLDeleteSync, "glDeleteSync");
+    ctx->getGLProcAddress(&fGLFenceSync, "glFenceSync", ext);
+    ctx->getGLProcAddress(&fGLClientWaitSync, "glClientWaitSync", ext);
+    ctx->getGLProcAddress(&fGLDeleteSync, "glDeleteSync", ext);
 }
 
 sk_gpu_test::PlatformFence GLFenceSync::insertFence() const {

tools/gpu/gl/iOS/CreatePlatformGLTestContext_iOS.mm

@@ -74,7 +74,7 @@
         }
         fEAGLContext = nil;
     }
-    if (RTLD_DEFAULT != fGLLibrary) {
+    if (nullptr != fGLLibrary) {
         dlclose(fGLLibrary);
     }
 }
@@ -89,7 +89,8 @@
 void IOSGLTestContext::onPlatformSwapBuffers() const { }
 
 GrGLFuncPtr IOSGLTestContext::onPlatformGetProcAddress(const char* procName) const {
-    return reinterpret_cast<GrGLFuncPtr>(dlsym(fGLLibrary, procName));
+    void* handle = (nullptr == fGLLibrary) ? RTLD_DEFAULT : fGLLibrary;
+    return reinterpret_cast<GrGLFuncPtr>(dlsym(handle, procName));
 }
 
 }  // anonymous namespace

tools/gpu/gl/mac/CreatePlatformGLTestContext_mac.cpp

@@ -89,7 +89,7 @@ void MacGLTestContext::destroyGLContext() {
         CGLReleaseContext(fContext);
         fContext = nullptr;
     }
-    if (RTLD_DEFAULT != fGLLibrary) {
+    if (nullptr != fGLLibrary) {
         dlclose(fGLLibrary);
     }
 }
@@ -103,7 +103,8 @@ void MacGLTestContext::onPlatformSwapBuffers() const {
 }
 
 GrGLFuncPtr MacGLTestContext::onPlatformGetProcAddress(const char* procName) const {
-    return reinterpret_cast<GrGLFuncPtr>(dlsym(fGLLibrary, procName));
+    void* handle = (nullptr == fGLLibrary) ? RTLD_DEFAULT : fGLLibrary;
+    return reinterpret_cast<GrGLFuncPtr>(dlsym(handle, procName));
 }
 
 }  // anonymous namespace

tools/ios_utils.h

@@ -14,7 +14,7 @@ extern "C" {
 
     // cd into the current app's Documents/ directory.
     // (This is the only directory we can easily read and write.)
-    void cd_Documents();
+    void cd_Documents(void);
 
 #if defined(__cplusplus)
 }