Win32: Remove timeGetTime fallback for timer

The performance counter API is guaranteed to succeed on Windows XP and
later so there is no need for a fallback.

This removes our last dependency on winmm.

src/win32_init.c

@@ -71,17 +71,6 @@ BOOL WINAPI DllMain(HINSTANCE instance, DWORD reason, LPVOID reserved)
 //
 static GLFWbool loadLibraries(void)
 {
-    _glfw.win32.winmm.instance = _glfwPlatformLoadModule("winmm.dll");
-    if (!_glfw.win32.winmm.instance)
-    {
-        _glfwInputErrorWin32(GLFW_PLATFORM_ERROR,
-                             "Win32: Failed to load winmm.dll");
-        return GLFW_FALSE;
-    }
-
-    _glfw.win32.winmm.GetTime = (PFN_timeGetTime)
-        _glfwPlatformGetModuleSymbol(_glfw.win32.winmm.instance, "timeGetTime");
-
     _glfw.win32.user32.instance = _glfwPlatformLoadModule("user32.dll");
     if (!_glfw.win32.user32.instance)
     {
@@ -179,9 +168,6 @@ static void freeLibraries(void)
     if (_glfw.win32.dinput8.instance)
         _glfwPlatformFreeModule(_glfw.win32.dinput8.instance);
 
-    if (_glfw.win32.winmm.instance)
-        _glfwPlatformFreeModule(_glfw.win32.winmm.instance);
-
     if (_glfw.win32.user32.instance)
         _glfwPlatformFreeModule(_glfw.win32.user32.instance);
 

src/win32_platform.h

@@ -266,10 +266,6 @@ typedef enum
 #define ERROR_INVALID_PROFILE_ARB 0x2096
 #define ERROR_INCOMPATIBLE_DEVICE_CONTEXTS_ARB 0x2054
 
-// winmm.dll function pointer typedefs
-typedef DWORD (WINAPI * PFN_timeGetTime)(void);
-#define timeGetTime _glfw.win32.winmm.GetTime
-
 // xinput.dll function pointer typedefs
 typedef DWORD (WINAPI * PFN_XInputGetCapabilities)(DWORD,DWORD,XINPUT_CAPABILITIES*);
 typedef DWORD (WINAPI * PFN_XInputGetState)(DWORD,XINPUT_STATE*);
@@ -459,11 +455,6 @@ typedef struct _GLFWlibraryWin32
     int                 rawInputSize;
     UINT                mouseTrailSize;
 
-    struct {
-        HINSTANCE                       instance;
-        PFN_timeGetTime                 GetTime;
-    } winmm;
-
     struct {
         HINSTANCE                       instance;
         PFN_DirectInput8Create          Create;
@@ -531,7 +522,6 @@ typedef struct _GLFWcursorWin32
 //
 typedef struct _GLFWtimerWin32
 {
-    GLFWbool            hasPC;
     uint64_t            frequency;
 } _GLFWtimerWin32;
 

src/win32_time.c

@@ -36,30 +36,14 @@
 
 void _glfwPlatformInitTimer(void)
 {
-    uint64_t frequency;
-
-    if (QueryPerformanceFrequency((LARGE_INTEGER*) &frequency))
-    {
-        _glfw.timer.win32.hasPC = GLFW_TRUE;
-        _glfw.timer.win32.frequency = frequency;
-    }
-    else
-    {
-        _glfw.timer.win32.hasPC = GLFW_FALSE;
-        _glfw.timer.win32.frequency = 1000;
-    }
+    QueryPerformanceFrequency((LARGE_INTEGER*) &_glfw.timer.win32.frequency);
 }
 
 uint64_t _glfwPlatformGetTimerValue(void)
 {
-    if (_glfw.timer.win32.hasPC)
-    {
-        uint64_t value;
-        QueryPerformanceCounter((LARGE_INTEGER*) &value);
-        return value;
-    }
-    else
-        return (uint64_t) timeGetTime();
+    uint64_t value;
+    QueryPerformanceCounter((LARGE_INTEGER*) &value);
+    return value;
 }
 
 uint64_t _glfwPlatformGetTimerFrequency(void)