8 files changed, 91 insertions, 1 deletions

diff --git a/src/core/file_sys/archive_backend.h b/src/core/file_sys/archive_backend.h
index 18c314884..1b510b695 100644
--- a/src/core/file_sys/archive_backend.h
+++ b/src/core/file_sys/archive_backend.h
@@ -200,6 +200,14 @@ public:
     virtual bool DeleteDirectory(const FileSys::Path& path) const = 0;
 
     /**
+     * Create a file specified by its path
+     * @param path Path relative to the Archive
+     * @param size The size of the new file, filled with zeroes
+     * @return File creation result code
+     */
+    virtual ResultCode CreateFile(const Path& path, u32 size) const = 0;
+
+    /**
      * Create a directory specified by its path
      * @param path Path relative to the archive
      * @return Whether the directory could be created
diff --git a/src/core/file_sys/archive_romfs.cpp b/src/core/file_sys/archive_romfs.cpp
index 1e3e9dc60..32d0777a0 100644
--- a/src/core/file_sys/archive_romfs.cpp
+++ b/src/core/file_sys/archive_romfs.cpp
@@ -58,6 +58,12 @@ bool Archive_RomFS::DeleteDirectory(const FileSys::Path& path) const {
     return false;
 }
 
+ResultCode Archive_RomFS::CreateFile(const Path& path, u32 size) const {
+    LOG_WARNING(Service_FS, "Attempted to create a file in ROMFS.");
+    // TODO: Verify error code
+    return ResultCode(ErrorDescription::NotAuthorized, ErrorModule::FS, ErrorSummary::NotSupported, ErrorLevel::Permanent);
+}
+
 /**
  * Create a directory specified by its path
  * @param path Path relative to the archive
diff --git a/src/core/file_sys/archive_romfs.h b/src/core/file_sys/archive_romfs.h
index 5b1ee6332..3f5cdebed 100644
--- a/src/core/file_sys/archive_romfs.h
+++ b/src/core/file_sys/archive_romfs.h
@@ -54,6 +54,14 @@ public:
     bool DeleteDirectory(const FileSys::Path& path) const override;
 
     /**
+     * Create a file specified by its path
+     * @param path Path relative to the Archive
+     * @param size The size of the new file, filled with zeroes
+     * @return File creation result code
+     */
+    ResultCode CreateFile(const Path& path, u32 size) const override;
+
+    /**
      * Create a directory specified by its path
      * @param path Path relative to the archive
      * @return Whether the directory could be created
diff --git a/src/core/file_sys/disk_archive.cpp b/src/core/file_sys/disk_archive.cpp
index eabf58057..f8096ebcf 100644
--- a/src/core/file_sys/disk_archive.cpp
+++ b/src/core/file_sys/disk_archive.cpp
@@ -35,6 +35,27 @@ bool DiskArchive::DeleteDirectory(const FileSys::Path& path) const {
     return FileUtil::DeleteDir(GetMountPoint() + path.AsString());
 }
 
+ResultCode DiskArchive::CreateFile(const FileSys::Path& path, u32 size) const {
+    std::string full_path = GetMountPoint() + path.AsString();
+
+    if (FileUtil::Exists(full_path))
+        return ResultCode(ErrorDescription::AlreadyExists, ErrorModule::FS, ErrorSummary::NothingHappened, ErrorLevel::Info);
+
+    if (size == 0) {
+        FileUtil::CreateEmptyFile(full_path);
+        return RESULT_SUCCESS;
+    }
+
+    FileUtil::IOFile file(full_path, "wb");
+    // Creates a sparse file (or a normal file on filesystems without the concept of sparse files)
+    // We do this by seeking to the right size, then writing a single null byte.
+    if (file.Seek(size - 1, SEEK_SET) && file.WriteBytes("", 1) == 1)
+        return RESULT_SUCCESS;
+
+    return ResultCode(ErrorDescription::TooLarge, ErrorModule::FS, ErrorSummary::OutOfResource, ErrorLevel::Info);
+}
+
+
 bool DiskArchive::CreateDirectory(const Path& path) const {
     return FileUtil::CreateDir(GetMountPoint() + path.AsString());
 }
diff --git a/src/core/file_sys/disk_archive.h b/src/core/file_sys/disk_archive.h
index 778c83953..eaec435d2 100644
--- a/src/core/file_sys/disk_archive.h
+++ b/src/core/file_sys/disk_archive.h
@@ -28,6 +28,7 @@ public:
     bool DeleteFile(const FileSys::Path& path) const override;
     bool RenameFile(const FileSys::Path& src_path, const FileSys::Path& dest_path) const override;
     bool DeleteDirectory(const FileSys::Path& path) const override;
+    ResultCode CreateFile(const Path& path, u32 size) const override;
     bool CreateDirectory(const Path& path) const override;
     bool RenameDirectory(const FileSys::Path& src_path, const FileSys::Path& dest_path) const override;
     std::unique_ptr<DirectoryBackend> OpenDirectory(const Path& path) const override;
diff --git a/src/core/hle/service/fs/archive.cpp b/src/core/hle/service/fs/archive.cpp
index 510d7320c..b7f97495c 100644
--- a/src/core/hle/service/fs/archive.cpp
+++ b/src/core/hle/service/fs/archive.cpp
@@ -330,6 +330,14 @@ ResultCode DeleteDirectoryFromArchive(ArchiveHandle archive_handle, const FileSy
                       ErrorSummary::Canceled, ErrorLevel::Status);
 }
 
+ResultCode CreateFileInArchive(Handle archive_handle, const FileSys::Path& path, u32 file_size) {
+    Archive* archive = GetArchive(archive_handle);
+    if (archive == nullptr)
+        return InvalidHandle(ErrorModule::FS);
+
+    return archive->backend->CreateFile(path, file_size);
+}
+
 ResultCode CreateDirectoryFromArchive(ArchiveHandle archive_handle, const FileSys::Path& path) {
     Archive* archive = GetArchive(archive_handle);
     if (archive == nullptr)
diff --git a/src/core/hle/service/fs/archive.h b/src/core/hle/service/fs/archive.h
index a128276b6..0fd3aaa0c 100644
--- a/src/core/hle/service/fs/archive.h
+++ b/src/core/hle/service/fs/archive.h
@@ -83,6 +83,15 @@ ResultCode RenameFileBetweenArchives(ArchiveHandle src_archive_handle, const Fil
 ResultCode DeleteDirectoryFromArchive(ArchiveHandle archive_handle, const FileSys::Path& path);
 
 /**
+ * Create a File in an Archive
+ * @param archive_handle Handle to an open Archive object
+ * @param path Path to the File inside of the Archive
+ * @param file_size The size of the new file, filled with zeroes
+ * @return File creation result code
+ */
+ResultCode CreateFileInArchive(Handle archive_handle, const FileSys::Path& path, u32 file_size);
+
+/**
  * Create a Directory from an Archive
  * @param archive_handle Handle to an open Archive object
  * @param path Path to the Directory inside of the Archive
diff --git a/src/core/hle/service/fs/fs_user.cpp b/src/core/hle/service/fs/fs_user.cpp
index 8b908d691..1402abe83 100644
--- a/src/core/hle/service/fs/fs_user.cpp
+++ b/src/core/hle/service/fs/fs_user.cpp
@@ -226,6 +226,35 @@ static void DeleteDirectory(Service::Interface* self) {
 }
 
 /*
+ * FS_User::CreateFile service function
+ *  Inputs:
+ *      0 : Command header 0x08080202
+ *      2 : Archive handle lower word
+ *      3 : Archive handle upper word
+ *      4 : File path string type
+ *      5 : File path string size
+ *      7 : File size (filled with zeroes)
+ *      10: File path string data
+ *  Outputs:
+ *      1 : Result of function, 0 on success, otherwise error code
+ */
+static void CreateFile(Service::Interface* self) {
+    u32* cmd_buff = Kernel::GetCommandBuffer();
+
+    ArchiveHandle archive_handle = MakeArchiveHandle(cmd_buff[2], cmd_buff[3]);
+    auto filename_type    = static_cast<FileSys::LowPathType>(cmd_buff[4]);
+    u32 filename_size     = cmd_buff[5];
+    u32 file_size         = cmd_buff[7];
+    u32 filename_ptr      = cmd_buff[10];
+
+    FileSys::Path file_path(filename_type, filename_size, filename_ptr);
+
+    LOG_DEBUG(Service_FS, "type=%d size=%d data=%s", filename_type, filename_size, file_path.DebugStr().c_str());
+
+    cmd_buff[1] = CreateFileInArchive(archive_handle, file_path, file_size).raw;
+}
+
+/*
  * FS_User::CreateDirectory service function
  *  Inputs:
  *      2 : Archive handle lower word
@@ -465,7 +494,7 @@ const FSUserInterface::FunctionInfo FunctionTable[] = {
     {0x08050244, RenameFile,            "RenameFile"},
     {0x08060142, DeleteDirectory,       "DeleteDirectory"},
     {0x08070142, nullptr,               "DeleteDirectoryRecursively"},
-    {0x08080202, nullptr,               "CreateFile"},
+    {0x08080202, CreateFile,            "CreateFile"},
     {0x08090182, CreateDirectory,       "CreateDirectory"},
     {0x080A0244, RenameDirectory,       "RenameDirectory"},
     {0x080B0102, OpenDirectory,         "OpenDirectory"},