internal override SqliteStatement Prepare(SqliteConnection cnn, string strSql, SqliteStatement previous,
uint timeout, out string strRemain)
{
SqliteStatementHandle stmt = null;
string ptr = null;
int len = 0;
int n = 17;
int retries = 0;
SqliteStatement cmd = null;
var rnd = new Random();
var starttick = (uint)Environment.TickCount;
while ((n == 17 || n == 6 || n == 5) && retries < 3)
{
n = UnsafeNativeMethods.sqlite3_prepare16(_sql, strSql, strSql.Length, out stmt, out ptr);
len = -1;
if (n == 17)
{
retries++;
}
else if (n == 1)
{
if (String.Compare(SQLiteLastError(), "near \"TYPES\": syntax error",
StringComparison.OrdinalIgnoreCase) == 0)
{
int pos = strSql.IndexOf(';');
if (pos == -1)
{
pos = strSql.Length - 1;
}
string typedefs = strSql.Substring(0, pos + 1);
strSql = strSql.Substring(pos + 1);
strRemain = "";
while (cmd == null && strSql.Length > 0)
{
cmd = Prepare(cnn, strSql, previous, timeout, out strRemain);
strSql = strRemain;
}
if (cmd != null)
{
cmd.SetTypes(typedefs);
}
return(cmd);
}
else if (_buildingSchema == false &&
String.Compare(SQLiteLastError(), 0, "no such table: TEMP.SCHEMA", 0, 26,
StringComparison.OrdinalIgnoreCase) == 0)
{
strRemain = "";
_buildingSchema = true;
try
{
while (cmd == null && strSql.Length > 0)
{
cmd = Prepare(cnn, strSql, previous, timeout, out strRemain);
strSql = strRemain;
}
return(cmd);
}
finally
{
_buildingSchema = false;
}
}
}
else if (n == 6 || n == 5) // Locked -- delay a small amount before retrying
{
// Keep trying, but if we've exceeded the command's timeout, give up and throw an error
if ((uint)Environment.TickCount - starttick > timeout)
{
throw new SqliteException(n, SQLiteLastError());
}
else
{
// Otherwise sleep for a random amount of time up to 150ms
Sleep(rnd.Next(1, 150));
}
}
}
if (n > 0)
{
throw new SqliteException(n, SQLiteLastError());
}
strRemain = UTF8ToString(ptr, len);
var hdl = stmt;
if (stmt != null)
{
cmd = new SqliteStatement(this, hdl, strSql.Substring(0, strSql.Length - strRemain.Length), previous);
}
return(cmd);
}
internal override SqliteStatement Prepare(SqliteConnection cnn, string strSql, SqliteStatement previous, uint timeoutMS, out string strRemain)
{
IntPtr stmt = IntPtr.Zero;
IntPtr ptr = IntPtr.Zero;
int len = 0;
int n = 17;
int retries = 0;
byte[] b = ToUTF8(strSql);
string typedefs = null;
SqliteStatement cmd = null;
Random rnd = null;
uint starttick = (uint)Environment.TickCount;
GCHandle handle = GCHandle.Alloc(b, GCHandleType.Pinned);
IntPtr psql = handle.AddrOfPinnedObject();
try
{
while ((n == 17 || n == 6 || n == 5) && retries < 3)
{
#if !SQLITE_STANDARD
n = UnsafeNativeMethods.sqlite3_prepare_interop(_sql, psql, b.Length - 1, out stmt, out ptr, out len);
#else
n = UnsafeNativeMethods.sqlite3_prepare(_sql, psql, b.Length - 1, out stmt, out ptr);
len = -1;
#endif
if (n == 17)
{
retries++;
}
else if (n == 1)
{
if (String.Compare(SQLiteLastError(), "near \"TYPES\": syntax error", StringComparison.OrdinalIgnoreCase) == 0)
{
int pos = strSql.IndexOf(';');
if (pos == -1)
{
pos = strSql.Length - 1;
}
typedefs = strSql.Substring(0, pos + 1);
strSql = strSql.Substring(pos + 1);
strRemain = "";
while (cmd == null && strSql.Length > 0)
{
cmd = Prepare(cnn, strSql, previous, timeoutMS, out strRemain);
strSql = strRemain;
}
if (cmd != null)
{
cmd.SetTypes(typedefs);
}
return(cmd);
}
#if PLATFORM_COMPACTFRAMEWORK
else if (_buildingSchema == false && String.Compare(SQLiteLastError(), 0, "no such table: TEMP.SCHEMA", 0, 26, StringComparison.OrdinalIgnoreCase) == 0)
{
strRemain = "";
_buildingSchema = true;
try
{
ISQLiteSchemaExtensions ext = ((IServiceProvider)SqliteFactory.Instance).GetService(typeof(ISQLiteSchemaExtensions)) as ISQLiteSchemaExtensions;
if (ext != null)
{
ext.BuildTempSchema(cnn);
}
while (cmd == null && strSql.Length > 0)
{
cmd = Prepare(cnn, strSql, previous, timeoutMS, out strRemain);
strSql = strRemain;
}
return(cmd);
}
finally
{
_buildingSchema = false;
}
}
#endif
}
else if (n == 6 || n == 5) // Locked -- delay a small amount before retrying
{
// Keep trying
if (rnd == null) // First time we've encountered the lock
{
rnd = new Random();
}
// If we've exceeded the command's timeout, give up and throw an error
if ((uint)Environment.TickCount - starttick > timeoutMS)
{
throw new SqliteException(n, SQLiteLastError());
}
else
{
// Otherwise sleep for a random amount of time up to 150ms
System.Threading.Thread.CurrentThread.Join(rnd.Next(1, 150));
}
}
}
if (n > 0)
{
throw new SqliteException(n, SQLiteLastError());
}
strRemain = UTF8ToString(ptr, len);
if (stmt != IntPtr.Zero)
{
cmd = new SqliteStatement(this, stmt, strSql.Substring(0, strSql.Length - strRemain.Length), previous);
}
return(cmd);
}
finally
{
handle.Free();
}
}
internal override SqliteStatement Prepare(string strSql, SqliteStatement previous, out string strRemain)
{
IntPtr stmt = IntPtr.Zero;
IntPtr ptr = IntPtr.Zero;
int n = 17;
int retries = 0;
byte[] b = ToUTF8(strSql);
string typedefs = null;
SqliteStatement cmd = null;
GCHandle handle = GCHandle.Alloc(b, GCHandleType.Pinned);
IntPtr psql = handle.AddrOfPinnedObject();
try
{
while (n == 17 && retries < 3)
{
try {
n = UnsafeNativeMethods.sqlite3_prepare_v2(_sql, psql, b.Length - 1, out stmt, out ptr);
} catch (EntryPointNotFoundException) {
n = UnsafeNativeMethods.sqlite3_prepare(_sql, psql, b.Length - 1, out stmt, out ptr);
}
retries++;
if (n == 1)
{
if (String.Compare(SqliteLastError(), "near \"TYPES\": syntax error", StringComparison.OrdinalIgnoreCase) == 0)
{
int pos = strSql.IndexOf(';');
if (pos == -1)
{
pos = strSql.Length - 1;
}
typedefs = strSql.Substring(0, pos + 1);
strSql = strSql.Substring(pos + 1);
strRemain = "";
while (cmd == null && strSql.Length > 0)
{
cmd = Prepare(strSql, previous, out strRemain);
strSql = strRemain;
}
if (cmd != null)
{
cmd.SetTypes(typedefs);
}
return(cmd);
}
}
}
if (n > 0)
{
throw new SqliteException(n, SqliteLastError());
}
strRemain = UTF8ToString(ptr);
if (stmt != IntPtr.Zero)
{
cmd = new SqliteStatement(this, stmt, strSql.Substring(0, strSql.Length - strRemain.Length), previous);
}
return(cmd);
}
finally
{
handle.Free();
}
}
