Commit cdb1b1b8 authored May 14, 2014 by Bao Haojun

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>

parent 32e4479d

adb/framebuffer_service.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -76,6 +76,7 @@ void framebuffer_service(int fd, void *cookie)
		exit(1);
		}

		close(fds[1]);
		fd_screencap = fds[0];

		/* read w, h & format */
		@@ -173,10 +174,9 @@ void framebuffer_service(int fd, void *cookie)
		}

		done:
		TEMP_FAILURE_RETRY(waitpid(pid, NULL, 0));

		close(fds[0]);
		close(fds[1]);

		TEMP_FAILURE_RETRY(waitpid(pid, NULL, 0));
		pipefail:
		close(fd);
		}