diff options
| -rw-r--r-- | sysdeps/mach/hurd/select.c | 50 |
1 files changed, 25 insertions, 25 deletions
diff --git a/sysdeps/mach/hurd/select.c b/sysdeps/mach/hurd/select.c index 3de8f209d2..84e89c5c05 100644 --- a/sysdeps/mach/hurd/select.c +++ b/sysdeps/mach/hurd/select.c @@ -23,6 +23,12 @@ Cambridge, MA 02139, USA. */ #include <stdlib.h> #include <string.h> +/* All user select types. */ +#define SELECT_ALL (SELECT_READ | SELECT_WRITE | SELECT_URG) + +/* Used to record that a particular select rpc returned. Must be distinct + from SELECT_ALL (which better not have the high bit set). */ +#define SELECT_RETURNED ((SELECT_ALL << 1) & ~SELECT_ALL) /* Check the first NFDS descriptors each in READFDS (if not NULL) for read readiness, in WRITEFDS (if not NULL) for write readiness, and in EXCEPTFDS @@ -137,8 +143,7 @@ DEFUN(__select, (nfds, readfds, writefds, exceptfds, timeout), /* We got an answer. This is not necessarily the answer to the query we sent just now. It may correspond to any prior query which timed out before its answer arrived. */ - if (tag < 0 || tag > i || - (type & (SELECT_READ|SELECT_URG|SELECT_WRITE)) == 0) + if (tag < 0 || tag > i || (type & SELECT_ALL) == 0) /* This is not a proper answer to any query we have yet made. */ err = EGRATUITOUS; @@ -146,6 +151,7 @@ DEFUN(__select, (nfds, readfds, writefds, exceptfds, timeout), { /* Some port is ready. TAG tells us which. */ types[tag] &= type; + types[tag] |= SELECT_RETURNED; ++got; } break; @@ -213,19 +219,16 @@ DEFUN(__select, (nfds, readfds, writefds, exceptfds, timeout), *(int *) &msg.success.tag_type != *(int *) &inttype || *(int *) &msg.success.result_type != *(int *) &inttype) __mach_msg_destroy (&msg); - else if ((msg.success.result & - (SELECT_READ|SELECT_WRITE|SELECT_URG)) == 0 || + else if ((msg.success.result & SELECT_ALL) == 0 || msg.success.tag < firstfd || msg.success.tag > lastfd) err = EGRATUITOUS; else { /* This is a winning io_select_reply message! Record the readiness it indicates and send a reply. */ - if (types[msg.success.tag] == 0) - /* This descriptor is ready and it was not before, - so we increment our count of ready descriptors. */ - ++got; - types[msg.success.tag] |= msg.success.result; + types[msg.success.tag] &= msg.success.result; + types[msg.success.tag] |= SELECT_RETURNED; + ++got; } } @@ -272,24 +275,21 @@ DEFUN(__select, (nfds, readfds, writefds, exceptfds, timeout), if (err) return __hurd_fail (err); - /* Set the user bitarrays. */ + /* Set the user bitarrays. We only ever have to clear bits, as all desired + ones are initially set. */ for (i = 0; i < nfds; ++i) { - if (readfds != NULL) - if (types[i] & SELECT_READ) - FD_SET (i, readfds); - else - FD_CLR (i, readfds); - if (writefds != NULL) - if (types[i] & SELECT_WRITE) - FD_SET (i, writefds); - else - FD_CLR (i, writefds); - if (exceptfds != NULL) - if (types[i] & SELECT_URG) - FD_SET (i, exceptfds); - else - FD_CLR (i, exceptfds); + int type = types[i]; + + if ((type & SELECT_RETURNED) == 0) + type = 0; + + if (readfds != NULL && (type & SELECT_READ) == 0) + FD_CLR (i, readfds); + if (writefds != NULL && (type & SELECT_WRITE) == 0) + FD_CLR (i, writefds); + if (exceptfds != NULL && (type & SELECT_URG) == 0) + FD_CLR (i, exceptfds); } return got; |