usr.bin/make: -j fix

The job option enable the usage of pipes to communicate with sub-makes.

On MINIX, it seems that there is possibility of receiving an EAGAIN on
such reads, even when it had previously been tested for POLLIN using
poll().

This patch is a workaround, by wrapping the read operation within a
do {} while(errno == EAGAIN && ...) loop.

Change-Id: Ia184c4d600efe7218d197820df87761604120862
This commit is contained in:
Lionel Sambuc 2014-04-25 16:06:33 +02:00
parent ac9fa699bd
commit 7d98eee859
2 changed files with 9 additions and 8 deletions

View file

@ -394,13 +394,6 @@ int count; /* max number of processes to release */
f->filp_vno != vp)
continue;
/* Do a pipe_check to see if we really want to callback this
* select; a close() doesn't always warrant it.
*/
if(pipe_check(f, op == VFS_READ ? READING : WRITING,
f->filp_flags, 1, 1) != EAGAIN) {
continue;
}
select_callback(f, selop);
f->filp_pipe_select_ops &= ~selop;

View file

@ -1380,7 +1380,7 @@ JobExec(Job *job, char **argv)
* by killing its process family, but not commit suicide.
*/
#if defined(MAKE_NATIVE) || defined(HAVE_SETPGID)
#if defined(SYSV) || defined(__minix)
#if defined(SYSV)
/* XXX: dsl - I'm sure this should be setpgrp()... */
(void)setsid();
#else
@ -2061,7 +2061,15 @@ Job_CatchOutput(void)
if (nready > 0 && readyfd(&childExitJob)) {
char token = 0;
ssize_t count;
#if defined(__minix)
/* Workaround: While the pipe is deemed ready to be read, it can still
* return EAGAIN in the read below. */
do {
#endif /* defined(__minix) */
count = read(childExitJob.inPipe, &token, 1);
#if defined(__minix)
} while(-1 == count && EAGAIN == errno);
#endif /* defined(__minix) */
switch (count) {
case 0:
Punt("unexpected eof on token pipe");