Remove workarounds for ancient kernels lacking __WALL

__WALL is available and working at least since 2.4 kernels: 10 years ago.

* strace (detach): Remove workarounds for ancient kernels lacking __WALL.
Add missing EINTR check.
(trace): Remove workarounds for ancient kernels lacking __WALL.
Remove redundant double error printout.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>

diff --git a/strace.c b/strace.c
index 5a2f139ba65633d63ad982da7f3aecb0cfc819a9..e94ca31c9bdf0bfc639088323cef557c335c7b10 100644 (file)
--- a/strace.c
+++ b/strace.c
@@ -806,33 +806,14 @@ detach(struct tcb *tcp)
        if (sigstop_expected || interrupt_done) {
                for (;;) {
                        int sig;
-#ifdef __WALL
                        if (waitpid(tcp->pid, &status, __WALL) < 0) {
+                               if (errno == EINTR)
+                                       continue;
                                if (errno == ECHILD) /* Already gone.  */
                                        break;
-                               if (errno != EINVAL) {
-                                       perror_msg("detach: waiting");
-                                       break;
-                               }
-#endif /* __WALL */
-                               /* No __WALL here.  */
-                               if (waitpid(tcp->pid, &status, 0) < 0) {
-                                       if (errno != ECHILD) {
-                                               perror_msg("detach: waiting");
-                                               break;
-                                       }
-#ifdef __WCLONE
-                                       /* If no processes, try clones.  */
-                                       if (waitpid(tcp->pid, &status, __WCLONE) < 0) {
-                                               if (errno != ECHILD)
-                                                       perror_msg("detach: waiting");
-                                               break;
-                                       }
-#endif /* __WCLONE */
-                               }
-#ifdef __WALL
+                               perror_msg("detach: waiting");
+                               break;
                        }
-#endif
                        if (!WIFSTOPPED(status)) {
                                /* Au revoir, mon ami. */
                                break;
@@ -1962,10 +1943,6 @@ static int
 trace(void)
 {
        struct rusage ru;
-       struct rusage *rup = cflag ? &ru : NULL;
-#ifdef __WALL
-       static int wait4_options = __WALL;
-#endif
 
        while (nprocs != 0) {
                int pid;
@@ -1977,47 +1954,25 @@ trace(void)
 
                if (interrupted)
                        return 0;
+
                if (interactive)
                        sigprocmask(SIG_SETMASK, &empty_set, NULL);
-#ifdef __WALL
-               pid = wait4(-1, &status, wait4_options, rup);
-               if (pid < 0 && (wait4_options & __WALL) && errno == EINVAL) {
-                       /* this kernel does not support __WALL */
-                       wait4_options &= ~__WALL;
-                       pid = wait4(-1, &status, wait4_options, rup);
-               }
-               if (pid < 0 && !(wait4_options & __WALL) && errno == ECHILD) {
-                       /* most likely a "cloned" process */
-                       pid = wait4(-1, &status, __WCLONE, rup);
-                       if (pid < 0) {
-                               perror_msg("wait4(__WCLONE) failed");
-                       }
-               }
-#else
-               pid = wait4(-1, &status, 0, rup);
-#endif /* __WALL */
+               pid = wait4(-1, &status, __WALL, (cflag ? &ru : NULL));
                wait_errno = errno;
                if (interactive)
                        sigprocmask(SIG_BLOCK, &blocked_set, NULL);
 
                if (pid < 0) {
-                       switch (wait_errno) {
-                       case EINTR:
+                       if (wait_errno == EINTR)
                                continue;
-                       case ECHILD:
-                               /*
-                                * We would like to verify this case
-                                * but sometimes a race in Solbourne's
-                                * version of SunOS sometimes reports
-                                * ECHILD before sending us SIGCHILD.
-                                */
+                       if (wait_errno == ECHILD)
+                               /* Should not happen since nprocs > 0 */
                                return 0;
-                       default:
-                               errno = wait_errno;
-                               perror_msg("wait");
-                               return -1;
-                       }
+                       errno = wait_errno;
+                       perror_msg("wait4(__WALL)");
+                       return -1;
                }
+
                if (pid == popen_pid) {
                        if (WIFEXITED(status) || WIFSIGNALED(status))
                                popen_pid = 0;