libbb: introduce and use safe_waitpid (loops in EINTR)

*: use more approproate (shorter) versions of wait()

function                                             old     new   delta
safe_waitpid                                           -      48     +48
wait_any_nohang                                        -      17     +17
send_tree                                            365     369      +4
processorstop                                        432     435      +3
text_yank                                            110     108      -2
make_human_readable_str                              202     200      -2
crond_main                                          1368    1366      -2
handle_sigchld                                        49      43      -6
reapchild                                            166     159      -7
custom                                               260     250     -10
checkscript                                          191     177     -14
wait_nohang                                           17       -     -17
wait_pid                                              43       -     -43
------------------------------------------------------------------------------
(add/remove: 2/2 grow/shrink: 2/7 up/down: 72/-103)           Total: -31 bytes

4 files changed, 6 insertions, 8 deletions

diff --git a/runit/runsv.c b/runit/runsv.c
index 8c5a4d4ea..84f5193f5 100644
--- a/runit/runsv.c
+++ b/runit/runsv.c
@@ -282,8 +282,7 @@ static unsigned custom(struct svdir *s, char c)
                                 execve(a, prog, environ);
                                 fatal_cannot("run control/?");
                         }
-                        while (wait_pid(&w, pid) == -1) {
-                                if (errno == EINTR) continue;
+                        while (safe_waitpid(pid, &w, 0) == -1) {
                                 warn_cannot("wait for child control/?");
                                 return 0;
                         }
@@ -593,7 +592,7 @@ int runsv_main(int argc, char **argv)
                         int child;
                         int wstat;
 
-                        child = wait_nohang(&wstat);
+                        child = wait_any_nohang(&wstat);
                         if (!child)
                                 break;
                         if ((child == -1) && (errno != EINTR))
diff --git a/runit/runsvdir.c b/runit/runsvdir.c
index 9e98ca6f8..838490376 100644
--- a/runit/runsvdir.c
+++ b/runit/runsvdir.c
@@ -252,7 +252,7 @@ int runsvdir_main(int argc, char **argv)
         for (;;) {
                 /* collect children */
                 for (;;) {
-                        pid = wait_nohang(&wstat);
+                        pid = wait_any_nohang(&wstat);
                         if (pid <= 0)
                                 break;
                         for (i = 0; i < svnum; i++) {
diff --git a/runit/sv.c b/runit/sv.c
index e31adffed..a89e24439 100644
--- a/runit/sv.c
+++ b/runit/sv.c
@@ -333,8 +333,7 @@ static int checkscript(void)
                 bb_perror_msg(WARN"cannot %s child %s/check", "run", *service);
                 return 0;
         }
-        while (wait_pid(&w, pid) == -1) {
-                if (errno == EINTR) continue;
+        while (safe_waitpid(pid, &w, 0) == -1) {
                 bb_perror_msg(WARN"cannot %s child %s/check", "wait for", *service);
                 return 0;
         }
diff --git a/runit/svlogd.c b/runit/svlogd.c
index 2dc8cb987..1d679c972 100644
--- a/runit/svlogd.c
+++ b/runit/svlogd.c
@@ -265,7 +265,7 @@ static unsigned processorstop(struct logdir *ld)
 
         if (ld->ppid) {
                 sig_unblock(SIGHUP);
-                while (wait_pid(&wstat, ld->ppid) == -1)
+                while (safe_waitpid(ld->ppid, &wstat, 0) == -1)
                         pause2cannot("wait for processor", ld->name);
                 sig_block(SIGHUP);
                 ld->ppid = 0;
@@ -794,7 +794,7 @@ static void sig_child_handler(int sig_no)
 
         if (verbose)
                 bb_error_msg(INFO"sig%s received", "child");
-        while ((pid = wait_nohang(&wstat)) > 0) {
+        while ((pid = wait_any_nohang(&wstat)) > 0) {
                 for (l = 0; l < dirn; ++l) {
                         if (dir[l].ppid == pid) {
                                 dir[l].ppid = 0;