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| author | Kaz Kylheku <kaz@kylheku.com> | 2021-03-16 20:34:07 -0700 |
|---|---|---|
| committer | Kaz Kylheku <kaz@kylheku.com> | 2021-03-16 20:34:07 -0700 |
| commit | 88d8fdbdd42b1960d548b05030282a79b5c6ad1f (patch) | |
| tree | bb9e78f67631fb326d447cd001e3dd46f578f5d9 | |
| parent | 4ee59957790a0c3c5fa9555b946239540e76ea27 (diff) | |
| download | txr-88d8fdbdd42b1960d548b05030282a79b5c6ad1f.tar.gz txr-88d8fdbdd42b1960d548b05030282a79b5c6ad1f.tar.bz2 txr-88d8fdbdd42b1960d548b05030282a79b5c6ad1f.zip | |
poll: iterate sequences efficiently.
* sysif.c (poll_wrap): Use seq_iter for efficience when
poll_list is a vector or other generalized sequence.
* txr.1: Change wording to say that poll-list is a sequence.
| -rw-r--r-- | sysif.c | 16 | ||||
| -rw-r--r-- | txr.1 | 2 |
2 files changed, 11 insertions, 7 deletions
@@ -1452,13 +1452,16 @@ static val poll_wrap(val poll_list, val timeout_in) { val self = lit("poll"); nfds_t i, len = c_num(length(poll_list), self); - val iter; + seq_iter_t iter; + val elem; struct pollfd *pfd = coerce(struct pollfd *, alloca(len * sizeof *pfd)); val timeout = default_arg(timeout_in, negone); int res; - for (i = 0, iter = poll_list; iter; iter = cdr(iter), i++) { - cons_bind (obj, events, car(iter)); + seq_iter_init(self, &iter, poll_list); + + for (i = 0; seq_get(&iter, &elem); i++) { + cons_bind (obj, events, elem); pfd[i].events = c_num(events, self); @@ -1504,10 +1507,11 @@ static val poll_wrap(val poll_list, val timeout_in) { list_collect_decl (out, ptail); - for (i = 0, iter = poll_list; iter; iter = cdr(iter), i++) { - val pair = car(iter); + seq_iter_init(self, &iter, poll_list); + + for (i = 0; seq_get(&iter, &elem); i++) { if (pfd[i].revents) - ptail = list_collect(ptail, cons(car(pair), num(pfd[i].revents))); + ptail = list_collect(ptail, cons(car(elem), num(pfd[i].revents))); } return out; @@ -64554,7 +64554,7 @@ for specified events. It is a wrapper for the same-named POSIX function. The .meta poll-list -argument is a list of +argument is a sequence of .code cons pairs. The .code car |