private static int GetFileVersion(string filePath)
{
if (IsVersion1(filePath))
{
return(1);
}
// Versions 2+ are SQLite databases. Open it and read the version number inside.
var sqlite = IntPtr.Zero; //sqlite3*
var stmt = IntPtr.Zero; // sqlite3_stmt*
try {
using NativeString filePathNative = new(filePath);
using NativeBuffer sqliteBuffer = new(IntPtr.Size);
var result = NativeMethods.sqlite3_open(filePathNative.Ptr, sqliteBuffer.Ptr);
if (result != NativeMethods.SQLITE_OK)
{
throw new Exception("This is not an SQL Notebook file.");
}
sqlite = Marshal.ReadIntPtr(sqliteBuffer.Ptr);
var versionSql = "SELECT version FROM _sqlnotebook_version";
using NativeString versionSqlNative = new(versionSql);
using NativeBuffer versionStmtNative = new(IntPtr.Size);
result = NativeMethods.sqlite3_prepare_v2(sqlite, versionSqlNative.Ptr, versionSqlNative.ByteCount,
versionStmtNative.Ptr, IntPtr.Zero);
stmt = Marshal.ReadIntPtr(versionStmtNative.Ptr); // sqlite3_stmt*
if (result != NativeMethods.SQLITE_OK || stmt == IntPtr.Zero)
{
// it's ok, a plain SQLite database is a valid version 2 SQL Notebook file
return(2);
}
if (NativeMethods.sqlite3_step(stmt) == NativeMethods.SQLITE_ROW)
{
return(NativeMethods.sqlite3_column_int(stmt, 0));
}
return(2); // missing version row; it's still a valid version 2 file
} finally {
if (stmt != IntPtr.Zero)
{
SqliteUtil.ThrowIfError(sqlite, NativeMethods.sqlite3_finalize(stmt));
}
if (sqlite != IntPtr.Zero)
{
SqliteUtil.ThrowIfError(IntPtr.Zero, NativeMethods.sqlite3_close(sqlite));
}
}
}