need to block SIGCHLD; ignore INT, QUIT, don't just block

[unix-history] / usr / src / lib / libc / stdlib / system.c

diff --git a/usr/src/lib/libc/stdlib/system.c b/usr/src/lib/libc/stdlib/system.c
index d42d806..d3c4853 100644 (file)
--- a/usr/src/lib/libc/stdlib/system.c
+++ b/usr/src/lib/libc/stdlib/system.c
@@ -16,7 +16,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)

-static char sccsid[] = "@(#)system.c   5.4 (Berkeley) %G%";
+static char sccsid[] = "@(#)system.c   5.5 (Berkeley) %G%";

 #endif /* LIBC_SCCS and not lint */
 
 #include <sys/types.h>
 #endif /* LIBC_SCCS and not lint */
 
 #include <sys/types.h>


@@ -29,19 +29,25 @@ system(command)
 {
        union wait pstat;
        pid_t pid, waitpid();
 {
        union wait pstat;
        pid_t pid, waitpid();

-       int omask;
+       int omask, (*i)(), (*q)();

 
 

+       omask = sigblock(sigmask(SIGCHLD));

        switch(pid = vfork()) {
        case -1:                        /* error */
        switch(pid = vfork()) {
        case -1:                        /* error */

+               (void)sigsetmask(omask);

                pstat.w_status = 0;
                pstat.w_retcode = 127;
                return(pstat.w_status);
        case 0:                         /* child */
                pstat.w_status = 0;
                pstat.w_retcode = 127;
                return(pstat.w_status);
        case 0:                         /* child */

+               (void)sigsetmask(omask);

                execl("/bin/sh", "sh", "-c", command, (char *)NULL);
                _exit(127);
        }
                execl("/bin/sh", "sh", "-c", command, (char *)NULL);
                _exit(127);
        }

-       omask = sigblock(sigmask(SIGINT)|sigmask(SIGQUIT)|sigmask(SIGHUP));
+       i = signal(SIGINT, SIG_IGN);
+       q = signal(SIGQUIT, SIG_IGN);

        pid = waitpid(pid, &pstat, 0);
        (void)sigsetmask(omask);
        pid = waitpid(pid, &pstat, 0);
        (void)sigsetmask(omask);

+       (void)signal(SIGINT, i);
+       (void)signal(SIGQUIT, q);

        return(pid == -1 ? -1 : pstat.w_status);
 }
        return(pid == -1 ? -1 : pstat.w_status);
 }