usign-exec: close writing end of pipe early in parent process

When the child process exited without producing output (for example
because usign was not found), the parent process would hang forever in
read(). By closing the writing end early in the parent process, read
will return as soon as no writing FDs are left - that is, when the child
process has exited.

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>

diff --git a/usign-exec.c b/usign-exec.c
index c9aecf99f9c05965157b92732bdd865391c01ab4..0dde81ed647b94a382044d97695fe25b497a4443 100644 (file)
--- a/usign-exec.c
+++ b/usign-exec.c
@@ -136,6 +136,8 @@ static int usign_f(char fingerprint[17], const char *pubkeyfile, const char *sec
                _exit(1);
        }
 
+       close(fds[1]);
+
        waitpid(pid, &status, 0);
        status = WEXITSTATUS(status);
        if (fingerprint && !WEXITSTATUS(status)) {
@@ -149,7 +151,6 @@ static int usign_f(char fingerprint[17], const char *pubkeyfile, const char *sec
 
        }
        close(fds[0]);
-       close(fds[1]);
        return status;
 }