hosversion: Attempt a non-tristate solution

nx/include/switch/kernel/detect.h

@@ -6,9 +6,14 @@
  */
 #pragma once
 #include "../types.h"
+#include "../runtime/hosversion.h"
+
+/// Returns the lowest known kernel version that is compatible with observation.
+u32 detectKernelVersion(void);
+
+/// Returns the highest possible known kernel version that is compatible with observation.
+u32 detectKernelVersionUpperBound(void);
 
-/// Returns the kernel version that can be detected by checking kernel capabilities. This only goes from 1 (representing 1.0.0) up to 6 (representing 6.0.0 and above). Generally, \ref hosversionGet should be used instead of this function.
-int detectKernelVersion(void);
 /// Returns true if the process has a debugger attached.
 bool detectDebugger(void);
 /// Returns true if the kernel is patched to allow self-process-jit.
@@ -18,25 +23,25 @@ void detectIgnoreJitKernelPatch(void);
 
 /// Returns true if the kernel version is equal to or above 2.0.0. Generally, \ref hosversionAtLeast should be used instead of this function.
 static inline bool kernelAbove200(void) {
-    return detectKernelVersion() >= 2;
+    return detectKernelVersion() >= MAKEHOSVERSION(2,0,0);
 }
 
 /// Returns true if the kernel version is equal to or above 3.0.0. Generally, \ref hosversionAtLeast should be used instead of this function.
 static inline bool kernelAbove300(void) {
-    return detectKernelVersion() >= 3;
+    return detectKernelVersion() >= MAKEHOSVERSION(3,0,0);
 }
 
 /// Returns true if the kernel version is equal to or above 4.0.0. Generally, \ref hosversionAtLeast should be used instead of this function.
 static inline bool kernelAbove400(void) {
-    return detectKernelVersion() >= 4;
+    return detectKernelVersion() >= MAKEHOSVERSION(4,0,0);
 }
 
 /// Returns true if the kernel version is equal to or above 5.0.0. Generally, \ref hosversionAtLeast should be used instead of this function.
 static inline bool kernelAbove500(void) {
-    return detectKernelVersion() >= 5;
+    return detectKernelVersion() >= MAKEHOSVERSION(5,0,0);
 }
 
 /// Returns true if the kernel version is equal to or above 6.0.0. Generally, \ref hosversionAtLeast should be used instead of this function.
 static inline bool kernelAbove600(void) {
-    return detectKernelVersion() >= 6;
+    return detectKernelVersion() >= MAKEHOSVERSION(6,0,0);
 }

nx/include/switch/runtime/hosversion.h

@@ -19,24 +19,18 @@
 /// Extracts the micro number from a HOS version value.
 #define HOSVER_MICRO(_version) ( (_version)        & 0xFF)
 
-/// Returns the current HOS version. Normally, this matches the version returned by \ref setsysGetFirmwareVersion or, if set:sys is not available, the version detected by \ref detectKernelVersion.
-u32 hosversionGet(void);
+void hosversionSetup(void);
 
 /// Sets or overrides the current HOS version. This function is normally called automatically by libnx on startup.
 void hosversionSet(u32 version);
 
 /// Returns true if the current HOS version is equal to or above the specified major/minor/micro version.
-static inline bool hosversionAtLeast(u8 major, u8 minor, u8 micro) {
-    return hosversionGet() >= MAKEHOSVERSION(major,minor,micro);
-}
+bool hosversionAtLeast(u8 major, u8 minor, u8 micro);
 
 /// Returns true if the current HOS version is earlier than the specified major/minor/micro version.
-static inline bool hosversionBefore(u8 major, u8 minor, u8 micro) {
-    return !hosversionAtLeast(major, minor, micro);
-}
+bool hosversionBefore(u8 major, u8 minor, u8 micro);
 
 /// Returns true if the current HOS version is between the two specified major versions, i.e. [major1, major2).
 static inline bool hosversionBetween(u8 major1, u8 major2) {
-    u32 ver = hosversionGet();
-    return ver >= MAKEHOSVERSION(major1,0,0) && ver < MAKEHOSVERSION(major2,0,0);
+    return hosversionAtLeast(major1, 0, 0) && hosversionBefore(major2, 0, 0);
 }

nx/source/applets/swkbd.c

@@ -51,14 +51,13 @@ static void _swkbdConfigClear(SwkbdConfig* c) {
 }
 
 static void _swkbdInitVersion(u32* version) {
-    u32 hosver = hosversionGet();
-    if (hosver >= MAKEHOSVERSION(5,0,0))
+    if (hosversionAtLeast(5,0,0))
         *version = 0x50009;
-    else if (hosver >= MAKEHOSVERSION(4,0,0))
+    else if (hosversionAtLeast(4,0,0))
         *version = 0x40008;
-    else if (hosver >= MAKEHOSVERSION(3,0,0))
+    else if (hosversionAtLeast(3,0,0))
         *version = 0x30007;
-    else if (hosver >= MAKEHOSVERSION(2,0,0))
+    else if (hosversionAtLeast(2,0,0))
         *version = 0x10006;
     else
         *version=0x5;//1.0.0+ version

nx/source/kernel/detect.c

@@ -4,12 +4,23 @@
 #include "kernel/detect.h"
 #include "kernel/mutex.h"
 #include "kernel/svc.h"
+#include "runtime/hosversion.h"
 #include <malloc.h>
 
 static bool g_VersionCached;
 static Mutex g_VersionMutex;
 static int g_Version;
 
+static u32 g_VersionBounds[] = {
+    MAKEHOSVERSION(1,0,0),
+    MAKEHOSVERSION(2,0,0),
+    MAKEHOSVERSION(3,0,0),
+    MAKEHOSVERSION(4,0,0),
+    MAKEHOSVERSION(5,0,0),
+    MAKEHOSVERSION(6,0,0),
+    UINT32_MAX
+};
+
 static bool g_JitKernelPatchCached;
 static Mutex g_JitKernelPatchMutex;
 static bool g_JitKernelPatchDetected;
@@ -27,17 +38,17 @@ static void _CacheVersion(void)
     }
 
     u64 tmp;
-    g_Version = 1;
+    g_Version = 0;
     if (R_VALUE(svcGetInfo(&tmp, 12, INVALID_HANDLE, 0)) != KERNELRESULT(InvalidEnumValue))
-        g_Version = 2;
+        g_Version = 1;
     if (R_VALUE(svcGetInfo(&tmp, 18, INVALID_HANDLE, 0)) != KERNELRESULT(InvalidEnumValue))
-        g_Version = 3;
+        g_Version = 2;
     if (R_VALUE(svcGetInfo(&tmp, 19, INVALID_HANDLE, 0)) != KERNELRESULT(InvalidEnumValue))
-        g_Version = 4;
+        g_Version = 3;
     if (R_VALUE(svcGetInfo(&tmp, 20, INVALID_HANDLE, 0)) != KERNELRESULT(InvalidEnumValue))
-        g_Version = 5;
+        g_Version = 4;
     if (R_VALUE(svcGetInfo(&tmp, 21, INVALID_HANDLE, 0)) != KERNELRESULT(InvalidEnumValue))
-        g_Version = 6;
+        g_Version = 5;
 
     __atomic_store_n(&g_VersionCached, true, __ATOMIC_SEQ_CST);
 
@@ -81,9 +92,14 @@ static void _CacheJitKernelPatch(void)
     mutexUnlock(&g_JitKernelPatchMutex);
 }
 
-int detectKernelVersion(void) {
+u32 detectKernelVersion(void) {
     _CacheVersion();
-    return g_Version;
+    return g_VersionBounds[g_Version];
+}
+
+u32 detectKernelVersionUpperBound(void) {
+    _CacheVersion();
+    return g_VersionBounds[g_Version + 1];
 }
 
 bool detectDebugger(void) {

nx/source/runtime/hosversion.c

@@ -1,13 +1,47 @@
 #include "runtime/hosversion.h"
+#include "kernel/detect.h"
+#include "services/fatal.h"
+
+static u32 g_kernelLowerBound;
+static u32 g_kernelUpperBound;
 
 static u32 g_hosVersion;
+static bool g_hasHosVersion;
 
-u32 hosversionGet(void)
+void hosversionSetup(void)
 {
-    return __atomic_load_n(&g_hosVersion, __ATOMIC_SEQ_CST);
+    g_kernelLowerBound = detectKernelVersion();
+    g_kernelUpperBound = detectKernelVersionUpperBound();
 }
 
 void hosversionSet(u32 version)
 {
-    __atomic_store_n(&g_hosVersion, version, __ATOMIC_SEQ_CST);
+    g_hosVersion = version;
+    g_hasHosVersion = true;
+}
+
+bool hosversionAtLeast(u8 major, u8 minor, u8 micro)
+{
+    u32 ver = MAKEHOSVERSION(major, minor, micro);
+
+    if (g_hasHosVersion)
+	return g_hosVersion >= ver;
+
+    if (g_kernelLowerBound >= ver)
+	return true;
+
+    fatalSimple(-1);
+}
+
+bool hosversionBefore(u8 major, u8 minor, u8 micro)
+{
+    u32 ver = MAKEHOSVERSION(major, minor, micro);
+
+    if (g_hasHosVersion)
+	return g_hosVersion < ver;
+
+    if (g_kernelUpperBound < ver)
+	return true;
+
+    fatalSimple(-1);
 }

nx/source/runtime/init.c

@@ -168,7 +168,7 @@ void __attribute__((weak)) __libnx_init(void* ctx, Handle main_thread, void* sav
 
     // Libnx initialization goes here.
     envSetup(ctx, main_thread, saved_lr);
-    hosversionSet(MAKEHOSVERSION(detectKernelVersion(), 0, 0));
+    hosversionSetup();
     newlibSetup();
     virtmemSetup();
     __libnx_initheap();

nx/source/services/audren.c

@@ -56,16 +56,15 @@ Result audrenInitialize(const AudioRendererConfig* config)
         return MAKERESULT(Module_Libnx, LibnxError_BadInput);
 
     // Choose revision (i.e. if splitters are used then at least revision 2 must be used)
-    u32 hosver = hosversionGet();
     /*if (hosver >= MAKEHOSVERSION(6,1,0))
         g_audrenRevision = AUDREN_REVISION_6;
     else if (hosver >= MAKEHOSVERSION(6,0,0))
         g_audrenRevision = AUDREN_REVISION_5;
-    else*/ if (hosver >= MAKEHOSVERSION(4,0,0))
+    else*/ if (hosversionAtLeast(4,0,0))
         g_audrenRevision = AUDREN_REVISION_4;
-    else if (hosver >= MAKEHOSVERSION(3,0,0))
+    else if (hosversionAtLeast(3,0,0))
         g_audrenRevision = AUDREN_REVISION_3;
-    else if (hosver >= MAKEHOSVERSION(2,0,0))
+    else if (hosversionAtLeast(2,0,0))
         g_audrenRevision = AUDREN_REVISION_2;
     else
         g_audrenRevision = AUDREN_REVISION_1;