logwrap: wait for child process when receiving SIGINT or SIGQUIT
- Wait for the child to exit before propagating SIGINT and SIGQUIT
to the parent
- Add ignore_int_quit argument to logwrap() that gives the caller the
option to ignore SIGINT and SIGQUIT while logwrap is running
Change-Id: If5c96cf23094917211310f00aa6aed515f110f5b
diff --git a/logwrapper/include/logwrap/logwrap.h b/logwrapper/include/logwrap/logwrap.h
index 722dda2..6593f3c 100644
--- a/logwrapper/include/logwrap/logwrap.h
+++ b/logwrapper/include/logwrap/logwrap.h
@@ -18,6 +18,8 @@
#ifndef __LIBS_LOGWRAP_H
#define __LIBS_LOGWRAP_H
+#include <stdbool.h>
+
__BEGIN_DECLS
/*
@@ -36,13 +38,17 @@
* NULL-terminated
* status: the equivalent child status as populated by wait(status). This
* value is only valid when logwrap successfully completes
+ * ignore_int_quit: set to true if you want to completely ignore SIGINT and
+ * SIGQUIT while logwrap is running. This may force the end-user to
+ * send a signal twice to signal the caller (once for the child, and
+ * once for the caller)
*
* Return value:
* 0 when logwrap successfully run the child process and captured its status
* -1 when an internal error occurred
*
*/
-int logwrap(int argc, char* argv[], int *status);
+int logwrap(int argc, char* argv[], int *status, bool ignore_int_quit);
__END_DECLS
diff --git a/logwrapper/logwrap.c b/logwrapper/logwrap.c
index ef457de..99a462f 100644
--- a/logwrapper/logwrap.c
+++ b/logwrapper/logwrap.c
@@ -176,13 +176,15 @@
write(signal_fd_write, &sig, 1);
}
-int logwrap(int argc, char* argv[], int *status) {
+int logwrap(int argc, char* argv[], int *status, bool ignore_int_quit) {
pid_t pid;
int parent_ptty;
int child_ptty;
char *child_devname = NULL;
struct sigaction chldact;
struct sigaction oldchldact;
+ struct sigaction intact;
+ struct sigaction quitact;
sigset_t blockset;
sigset_t oldset;
int sockets[2];
@@ -204,6 +206,8 @@
}
sigemptyset(&blockset);
+ sigaddset(&blockset, SIGINT);
+ sigaddset(&blockset, SIGQUIT);
sigaddset(&blockset, SIGCHLD);
sigprocmask(SIG_BLOCK, &blockset, &oldset);
@@ -231,6 +235,8 @@
fatal("This should never happen\n");
return -1;
} else {
+ struct sigaction ignact;
+
memset(&chldact, 0, sizeof(chldact));
chldact.sa_handler = sigchld_handler;
chldact.sa_flags = SA_NOCLDSTOP;
@@ -245,6 +251,13 @@
"handler and might cause interaction issues");
}
+ if (ignore_int_quit) {
+ memset(&ignact, 0, sizeof(ignact));
+ ignact.sa_handler = SIG_IGN;
+ sigaction(SIGINT, &ignact, &intact);
+ sigaction(SIGQUIT, &ignact, &quitact);
+ }
+
rc = socketpair(AF_UNIX, SOCK_STREAM, 0, sockets);
if (rc == -1) {
char msg[40];
@@ -268,6 +281,10 @@
close(sockets[0]);
close(sockets[1]);
err_socketpair:
+ if (ignore_int_quit) {
+ sigaction(SIGINT, &intact, NULL);
+ sigaction(SIGQUIT, &quitact, NULL);
+ }
sigaction(SIGCHLD, &oldchldact, NULL);
err_fork:
sigprocmask(SIG_SETMASK, &oldset, NULL);
diff --git a/logwrapper/logwrapper.c b/logwrapper/logwrapper.c
index e647b4d..563fcee 100644
--- a/logwrapper/logwrapper.c
+++ b/logwrapper/logwrapper.c
@@ -59,7 +59,7 @@
usage();
}
- rc = logwrap(argc - 1, &argv[1], &status);
+ rc = logwrap(argc - 1, &argv[1], &status, true);
if (!rc) {
if (WIFEXITED(status))
rc = WEXITSTATUS(status);