From 5182b57a1d7eab36e21f36fa79bb549a0d6ad2d8 Mon Sep 17 00:00:00 2001
From: yellows8 <yellows8@users.noreply.github.com>
Date: Thu, 28 Nov 2019 18:51:52 -0500
Subject: [PATCH] fs/fs_dev: Added
 FsFileSystemQueryId_IsValidSignedSystemPartitionOnSdCard,
 fsFsIsValidSignedSystemPartitionOnSdCard, and
 fsdevIsValidSignedSystemPartitionOnSdCard. Improved docs.

---
 nx/include/switch/runtime/devices/fs_dev.h |  3 +++
 nx/include/switch/services/fs.h            |  8 +++++++-
 nx/source/runtime/devices/fs_dev.c         | 10 ++++++++++
 nx/source/services/fs.c                    | 10 ++++++++++
 4 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/nx/include/switch/runtime/devices/fs_dev.h b/nx/include/switch/runtime/devices/fs_dev.h
index 86fdcf6b..0d36e609 100644
--- a/nx/include/switch/runtime/devices/fs_dev.h
+++ b/nx/include/switch/runtime/devices/fs_dev.h
@@ -56,6 +56,9 @@ int fsdevTranslatePath(const char *path, FsFileSystem** device, char *outpath);
 /// This calls fsFsSetConcatenationFileAttribute on the filesystem specified by the input path (as used in stdio).
 Result fsdevSetConcatenationFileAttribute(const char *path);
 
+// Uses \ref fsFsIsValidSignedSystemPartitionOnSdCard with the specified device.
+Result fsdevIsValidSignedSystemPartitionOnSdCard(const char *name, bool *out);
+
 /// This calls fsFsCreateFile on the filesystem specified by the input path (as used in stdio).
 Result fsdevCreateFile(const char* path, size_t size, u32 flags);
 
diff --git a/nx/include/switch/services/fs.h b/nx/include/switch/services/fs.h
index 86a33de2..7d4ad8f5 100644
--- a/nx/include/switch/services/fs.h
+++ b/nx/include/switch/services/fs.h
@@ -272,8 +272,10 @@ typedef enum {
     FsFileSystemType_RegisteredUpdate   = 8,  ///< [4.0.0+] RegisteredUpdate
 } FsFileSystemType;
 
+/// FileSystemQueryId
 typedef enum {
-    FsFileSystemQueryId_SetConcatenationFileAttribute = 0,
+    FsFileSystemQueryId_SetConcatenationFileAttribute           = 0,  ///< [4.0.0+]
+    FsFileSystemQueryId_IsValidSignedSystemPartitionOnSdCard    = 2,  ///< [8.0.0+]
 } FsFileSystemQueryId;
 
 /// FsPriority
@@ -380,6 +382,10 @@ void fsFsClose(FsFileSystem* fs);
 /// This will cause HOS to treat the directory as if it were a file containing the directory's concatenated contents.
 Result fsFsSetConcatenationFileAttribute(FsFileSystem* fs, const char *path);
 
+/// Wrapper for fsFsQueryEntry with FsFileSystemQueryId_IsValidSignedSystemPartitionOnSdCard.
+/// Only available on [8.0.0+].
+Result fsFsIsValidSignedSystemPartitionOnSdCard(FsFileSystem* fs, bool *out);
+
 // IFile
 Result fsFileRead(FsFile* f, s64 off, void* buf, u64 read_size, u32 option, u64* bytes_read);
 Result fsFileWrite(FsFile* f, s64 off, const void* buf, u64 write_size, u32 option);
diff --git a/nx/source/runtime/devices/fs_dev.c b/nx/source/runtime/devices/fs_dev.c
index 634552da..a70b7418 100644
--- a/nx/source/runtime/devices/fs_dev.c
+++ b/nx/source/runtime/devices/fs_dev.c
@@ -407,6 +407,16 @@ Result fsdevSetConcatenationFileAttribute(const char *path) {
   return fsFsSetConcatenationFileAttribute(&device->fs, fs_path);
 }
 
+Result fsdevIsValidSignedSystemPartitionOnSdCard(const char *name, bool *out) {
+  fsdev_fsdevice *device;
+
+  device = fsdevFindDevice(name);
+  if(device==NULL)
+    return MAKERESULT(Module_Libnx, LibnxError_NotFound);
+
+  return fsFsIsValidSignedSystemPartitionOnSdCard(&device->fs, out);
+}
+
 Result fsdevCreateFile(const char* path, size_t size, u32 flags) {
   char           *fs_path = __nx_dev_path_buf;
   fsdev_fsdevice *device = NULL;
diff --git a/nx/source/services/fs.c b/nx/source/services/fs.c
index 745a2c1e..8ab67afa 100644
--- a/nx/source/services/fs.c
+++ b/nx/source/services/fs.c
@@ -635,6 +635,16 @@ Result fsFsSetConcatenationFileAttribute(FsFileSystem* fs, const char *path) {
     return fsFsQueryEntry(fs, NULL, 0, NULL, 0, path, FsFileSystemQueryId_SetConcatenationFileAttribute);
 }
 
+Result fsFsIsValidSignedSystemPartitionOnSdCard(FsFileSystem* fs, bool *out) {
+    if (hosversionBefore(8,0,0))
+        return MAKERESULT(Module_Libnx, LibnxError_IncompatSysVer);
+
+    u8 tmp=0;
+    Result rc = fsFsQueryEntry(fs, &tmp, sizeof(tmp), NULL, 0, "/", FsFileSystemQueryId_IsValidSignedSystemPartitionOnSdCard);
+    if (R_SUCCEEDED(rc) && out) *out = tmp & 1;
+    return rc;
+}
+
 void fsFsClose(FsFileSystem* fs) {
     _fsObjectClose(&fs->s);
 }