Fix deadlocks.
1. Close pipe fds[1] as soon as possible. Otherwise it may block when
reading from fds[0] even though the child process has exited early
and closed its copy of fds[1].
2. Waitpid after pipe is closed. Otherwise the screencap child process
may block while writing fds[1], because the fds[0] is not closed
yet. If we close fds[0] first, then the screencap child process will
die because of SIGPIPE, and waitpid will return correctly.
Change-Id: I433c95a5ba2eb3045727fc39a49fd9557fb1a1d1
Signed-off-by: Bao Haojun <baohaojun@gmail.com>
diff --git a/adb/framebuffer_service.c b/adb/framebuffer_service.c
index fa7fd98..e42dcbf 100644
--- a/adb/framebuffer_service.c
+++ b/adb/framebuffer_service.c
@@ -76,6 +76,7 @@
exit(1);
}
+ close(fds[1]);
fd_screencap = fds[0];
/* read w, h & format */
@@ -173,10 +174,9 @@
}
done:
- TEMP_FAILURE_RETRY(waitpid(pid, NULL, 0));
-
close(fds[0]);
- close(fds[1]);
+
+ TEMP_FAILURE_RETRY(waitpid(pid, NULL, 0));
pipefail:
close(fd);
}