State update for filewriter was missing and that caused Maxscale to fail if opening of any log file failed.
dcb.c:
Added EAGAIN and EWOULDBLOCK handling to dcb_read. If dcb_close is called for freshly created dcb, dcb is only freed.
gateway.c:
Added file_write_footer and write_footer of which the latter is called at exit time. It simply draws a line to screen.
gw_utils.c:
Some macros for helping comparison between gw_read_gwbuff and dcb_read, which overlap.
poll.c:
Some macros to help enable/disable mutexing in poll_waitevents
service.c:
Check return value of listen and session_alloc and behave accordingly.
mysql_client.c:
If ioctl returned successfully with b==0 it earlier caused closing the client and backend dcbs. Since that doesn't reliably indicate that client has closed socket on its side, Maxscale doesn't close its sockets either.
mysql_common.c:
In gw_receive_backend_auth, if dcb_read returns n==0, it is not considered as an error anymore. The implemented behavior is not yet complete and correct. Result should be successful but the protocol state shouldn't change to MYSQL_IDLE before backend return is received.
In gw_send_authentication_to_backend protocol state was always set to MYSQL_AUTH_RECV even if gw_rwite had failed. Now, return value is read and state is set in caller's context basen on the return value.
skygw_utils.cc:
Removed ss_dassert from skyge_file_init because it prevented from returning meaningful error meassage to the client.:
- Checked argument types and counts
- Removed trailing line feeds
- Removed thread ids from error logs (they are used in trace / debug log
- Added some state information to dcbs
- Added prefix 'Error' or 'Fatal' to error logs.
- Switches all error logs to use flushing log write.
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Removed DCB states DCB_STATE_IDLE, and DCB_STATE_PROCESSING.
Added DCB_STATE_UNDEFINED for initial content for state variable which doesn't have any specific value set, and DCB_STATE_NOPOLLING to indicate that dcb has been removed from poll set.
Added following dcb roles: DCB_ROLE_SERVICE_LISTENER for listeners of services, and DCB_ROLE_REQUEST_HANDLER for client/backend dcbs. Listeners may have state DCB_STATE_LISTENING, but not DCB_STATE_POLLING. Request handlers may have DCB_STATE_POLLING but not DCB_STATE_LISTENING. Role is passed as an argument to dcb.c:dcb_alloc.
From now on, struct check numbers of DCB are included and checked in DEBUG build only.
Added dcb_role_t dcb_role-member to DCB as well as SPINLOCK dcb_initlock, which protects state changes.
Removed extern keyword from function declarations because functions are by default externally visible if they are declared in header.
dcb.b
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Function dcb_set_state, and dcb_set_state_nomutex provide functions for changing dcb states. Latter implements a state machine for dcb.
Function dcb_add_to_zombieslist replaces dcb_free. It adds in atomic step dcb to zombieslist and changes state to DCB_STATE_ZOMBIE.
Function dcb_final_free removes dcb from allDCBs list, terminates router and client sessions, and frees dcb and related memory.
Function dcb_process_zombies removes executing thread from dcb's bitmask, and it there are no further thread bits, moves dcb to a victim list, and finally, for each dcb on victim list, closes fd and sets state to DCB_STATE_DISCONNECTED.
Function dcb_close sets dcb state to DCB_STATE_NOPOLLIN, removes dcb from poll set and sets bit to bitmask for each server thread in an atomic step.
poll.c
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Function poll_add_dcb sets either DCB_STATE_LISTENING or DCB_STATE_POLLING state for newly created dcb, depending whether the role of dcb is DCB_ROLE_SERVICE_LISTENER, or DCB_ROLE_REQUEST_HANDLER, respectively. Then dcb is set to poll set.
poll_waitevents : commented out code which skipped event if dcb was added to zombieslist or if fd was closed. Added state checks.
service.c : Minor changes.
httpd.c : Removed dcb state changes. They are done in core.
mysql_backend.c : Added checks, removed dcb state changes.
mysql_client.c : Removed dcb state changes. Added checks.
mysql_common.c : Minor changes
telnetd.c : Removed state changes. Replaced some typecasts and pointer references with local variable reads.
skygw_debug.h : Removed two states, and added two to state printing macro.
