Fix unlikely races with GnuTLS, datagrams
Retry some calls if interrupted at inopportune times. These were found by code inspection. * src/gnutls.c (gnutls_try_handshake): Simplify by using new emacs_gnutls_handle_error API. (emacs_gnutls_write): Remove GNUTLS_E_AGAIN hack since emacs_gnutls_handle_error now does that. Use emacs_gnutls_handle_error only on errors. (emacs_gnutls_read): Retry if gnutls_record_recv returns GNUTLS_E_INTERRUPTED, to be consistent with emacs_read. (emacs_gnutls_handle_error): Return 0 on fatal errors, -1 (setting errno) on ordinary errors, to simplify callers. Assume that ERR is negative, since it always is now. Map non-fatal GnuTLS errors to errno values as best we can. * src/process.c (read_process_output) [DATAGRAM_SOCKETS]: Retry recvfrom if it is interrupted, to be consistent with how things are handled when not a datagram channel. (send_process) [DATAGRAM_SOCEKTS]: If sendto is interrupted, process pending signals and retry it, to be consistent with how things are handled when not a datagram channel.
Showing with 74 additions and 50 deletions