This shows the beginning of Sor’s Sonata in C op. 15(b), which dates from Sor’s time in Spain and was first published in about 1810 or shortly before.
The complete Sonata in C op. 15(b) by Sor is available from Tecla Editions at www.tecla.com as part of the new 2019 second edition of Sor’s New Complete Works for Guitar edited by Brian Jeffery. For details about Sor’s music and his biography, please see www.tecla.com.