source: ps/trunk/source/lib/sysdep/os/osx/osx_sys_version.mm

/* Copyright (C) 2013 Wildfire Games.
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#import <AvailabilityMacros.h> // MAC_OS_X_VERSION_MIN_REQUIRED
#import <Foundation/Foundation.h>
#import <dispatch/dispatch.h>
#import <string>

#import "osx_sys_version.h"

void GetSystemVersion(int &major, int &minor, int &bugfix)
{
    // grand central dispatch only available on 10.6+
#if MAC_OS_X_VERSION_MIN_REQUIRED >= 1060
    if (dispatch_once != nil)
    {
        // sensible default
        static int mMajor = 10;
        static int mMinor = 8;
        static int mBugfix = 0;

        static dispatch_once_t onceToken;
        dispatch_once(&onceToken, ^{
            NSString* versionString = [[NSDictionary dictionaryWithContentsOfFile:@"/System/Library/CoreServices/SystemVersion.plist"] objectForKey:@"ProductVersion"];
            NSArray* versions = [versionString componentsSeparatedByString:@"."];

            if (versions.count >= 1)
                mMajor = [[versions objectAtIndex:0] integerValue];
            if (versions.count >= 2)
                mMinor = [[versions objectAtIndex:1] integerValue];
            if (versions.count >= 3)
                mBugfix = [[versions objectAtIndex:2] integerValue];
        });

        major = mMajor;
        minor = mMinor;
        bugfix = mBugfix;
    }
    else
    {
#endif  // fallback to 10.5 API
        // just return 10.5.0, it's unlikely we support an earlier OS
        // and unlikely we care about bugfix versions
        major = 10;
        minor = 5;
        bugfix = 0;
#if MAC_OS_X_VERSION_MIN_REQUIRED >= 1060
    }
#endif
}