Re: \if, \elseif, \else, \endif (was Re: PSQL commands: \quit_if, \quit_unless)

Corey Huinker wrote:

[about Ctrl-C]

> That does seem to be the consensus desired behavior. I'm just not sure
> where to handle that. The var "cancel_pressed" shows up in a lot of places.
> Advice?

Probably you don't need to care about cancel_pressed, and
the /if stack could be unwound at the point the SIGINT
handler longjumps to, in mainloop.c:

/* got here with longjmp */

/* reset parsing state */
psql_scan_finish(scan_state);
psql_scan_reset(scan_state);
resetPQExpBuffer(query_buf);
resetPQExpBuffer(history_buf);
count_eof = 0;
slashCmdStatus = PSQL_CMD_UNKNOWN;
prompt_status = PROMPT_READY;
pset.stmt_lineno = 1;
cancel_pressed = false;

The check I was suggesting on whether Ctrl+C has been pressed
on an empty line seems harder to implement, because get_interactive()
just calls readline() or fgets(), which block to return when a whole
line is ready. AFAICS psql can't know what was the edit-in-progress
when these functions are interrupted by a signal instead of
returning normally.
But I don't think this check is essential, it could be left to another patch.

Best regards,
--
Daniel Vérité
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