Patch from Sylvain to fix clang warnings

src/power/SDL_power.c

@@ -20,6 +20,7 @@
 */
 #include "../SDL_internal.h"
 #include "SDL_power.h"
+#include "SDL_syspower.h"
 
 /*
  * Returns SDL_TRUE if we have a definitive answer.
@@ -29,18 +30,6 @@ typedef SDL_bool
     (*SDL_GetPowerInfo_Impl) (SDL_PowerState * state, int *seconds,
                               int *percent);
 
-SDL_bool SDL_GetPowerInfo_Linux_sys_class_power_supply(SDL_PowerState *, int *, int *);
-SDL_bool SDL_GetPowerInfo_Linux_proc_acpi(SDL_PowerState *, int *, int *);
-SDL_bool SDL_GetPowerInfo_Linux_proc_apm(SDL_PowerState *, int *, int *);
-SDL_bool SDL_GetPowerInfo_Windows(SDL_PowerState *, int *, int *);
-SDL_bool SDL_GetPowerInfo_MacOSX(SDL_PowerState *, int *, int *);
-SDL_bool SDL_GetPowerInfo_Haiku(SDL_PowerState *, int *, int *);
-SDL_bool SDL_GetPowerInfo_UIKit(SDL_PowerState *, int *, int *);
-SDL_bool SDL_GetPowerInfo_Android(SDL_PowerState *, int *, int *);
-SDL_bool SDL_GetPowerInfo_PSP(SDL_PowerState *, int *, int *);
-SDL_bool SDL_GetPowerInfo_WinRT(SDL_PowerState *, int *, int *);
-SDL_bool SDL_GetPowerInfo_Emscripten(SDL_PowerState *, int *, int *);
-
 #ifndef SDL_POWER_DISABLED
 #ifdef SDL_POWER_HARDWIRED
 /* This is for things that _never_ have a battery */

src/power/SDL_syspower.h

@@ -0,0 +1,68 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+#include "../SDL_internal.h"
+
+/* These are functions that need to be implemented by a port of SDL */
+
+#ifndef _SDL_syspower_h
+#define _SDL_syspower_h
+
+#include "SDL_power.h"
+
+#ifndef SDL_POWER_DISABLED
+#ifdef SDL_POWER_LINUX          /* in order of preference. More than could work. */
+SDL_bool SDL_GetPowerInfo_Linux_sys_class_power_supply(SDL_PowerState *, int *, int *);
+SDL_bool SDL_GetPowerInfo_Linux_proc_acpi(SDL_PowerState *, int *, int *);
+SDL_bool SDL_GetPowerInfo_Linux_proc_apm(SDL_PowerState *, int *, int *);
+#endif
+#ifdef SDL_POWER_WINDOWS        /* handles Win32, Win64, PocketPC. */
+SDL_bool SDL_GetPowerInfo_Windows(SDL_PowerState *, int *, int *);
+#endif
+#ifdef SDL_POWER_UIKIT          /* handles iPhone/iPad/etc */
+SDL_bool SDL_GetPowerInfo_UIKit(SDL_PowerState *, int *, int *);
+#endif
+#ifdef SDL_POWER_MACOSX         /* handles Mac OS X, Darwin. */
+SDL_bool SDL_GetPowerInfo_MacOSX(SDL_PowerState *, int *, int *);
+#endif
+#ifdef SDL_POWER_HAIKU          /* with BeOS euc.jp apm driver. Does this work on Haiku? */
+SDL_bool SDL_GetPowerInfo_Haiku(SDL_PowerState *, int *, int *);
+#endif
+#ifdef SDL_POWER_ANDROID        /* handles Android. */
+SDL_bool SDL_GetPowerInfo_Android(SDL_PowerState *, int *, int *);
+#endif
+#ifdef SDL_POWER_PSP        /* handles PSP. */
+SDL_bool SDL_GetPowerInfo_PSP(SDL_PowerState *, int *, int *);
+#endif
+#ifdef SDL_POWER_WINRT          /* handles WinRT */
+SDL_bool SDL_GetPowerInfo_WinRT(SDL_PowerState *, int *, int *);
+#endif
+#ifdef SDL_POWER_EMSCRIPTEN     /* handles Emscripten */
+SDL_bool SDL_GetPowerInfo_Emscripten(SDL_PowerState *, int *, int *);
+#endif
+
+#ifdef SDL_POWER_HARDWIRED
+SDL_bool SDL_GetPowerInfo_Hardwired(SDL_PowerState *, int *, int *);
+#endif
+#endif
+
+#endif /* _SDL_syspower_h */
+
+/* vi: set ts=4 sw=4 expandtab: */

src/power/linux/SDL_syspower.c

@@ -32,6 +32,7 @@
 #include <fcntl.h>
 
 #include "SDL_power.h"
+#include "../SDL_syspower.h"
 
 static const char *proc_apm_path = "/proc/apm";
 static const char *proc_acpi_battery_path = "/proc/acpi/battery";