Add a safety check to prevent apps from running on unsupported OSes

Although Qt declares its minimum supported OS version to the compiler
and linker, the OS ignores this information when loading shared
libraries, so instead of failing with a useful error message, the
program will simply crash at runtime. This attempts to bring that
failure as early in the lifecycle as possible, and provide a better
error message as well.

Change-Id: Ic58b44f8895eac718c94e62cad6e2506dbea8a7e
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

1 files changed, 30 insertions, 0 deletions

diff --git a/src/corelib/kernel/qcore_mac_objc.mm b/src/corelib/kernel/qcore_mac_objc.mm
index 02e1232c64..ce4f01625e 100644
--- a/src/corelib/kernel/qcore_mac_objc.mm
+++ b/src/corelib/kernel/qcore_mac_objc.mm
@@ -280,6 +280,36 @@ Qt::Key qt_mac_cocoaKey2QtKey(QChar keyCode)
 
 #endif // Q_OS_OSX
 
+void qt_apple_check_os_version()
+{
+#if defined(__IPHONE_OS_VERSION_MIN_REQUIRED)
+    const char *os = "iOS";
+    const int version = __IPHONE_OS_VERSION_MIN_REQUIRED;
+#elif defined(__TV_OS_VERSION_MIN_REQUIRED)
+    const char *os = "tvOS";
+    const int version = __TV_OS_VERSION_MIN_REQUIRED;
+#elif defined(__WATCH_OS_VERSION_MIN_REQUIRED)
+    const char *os = "watchOS";
+    const int version = __WATCH_OS_VERSION_MIN_REQUIRED;
+#elif defined(__MAC_OS_X_VERSION_MIN_REQUIRED)
+    const char *os = "macOS";
+    const int version = __MAC_OS_X_VERSION_MIN_REQUIRED;
+#endif
+    const NSOperatingSystemVersion required = version >= 100000
+    ? (NSOperatingSystemVersion){version / 10000, version / 100 % 100, version % 100}
+    : (NSOperatingSystemVersion){version / 100, version / 10 % 10, version % 10};
+    const NSOperatingSystemVersion current = NSProcessInfo.processInfo.operatingSystemVersion;
+    if (![NSProcessInfo.processInfo isOperatingSystemAtLeastVersion:required]) {
+        fprintf(stderr, "You can't use this version of %s with this version of %s. "
+                "You have %s %ld.%ld.%ld. Qt requires %s %ld.%ld.%ld or later.\n",
+                ((NSString *)NSBundle.mainBundle.infoDictionary[@"CFBundleName"]).UTF8String,
+                os,
+                os, current.majorVersion, current.minorVersion, current.patchVersion,
+                os, required.majorVersion, required.minorVersion, required.patchVersion);
+        abort();
+    }
+}
+
 // -------------------------------------------------------------------------
 
 QT_END_NAMESPACE