tree-wide: make use of wait_for_terminate_and_check() at various places

Using wait_for_terminate_and_check() instead of wait_for_terminate()
let's us simplify, shorten and unify the return value checking and
logging of waitid().  Hence, let's use it all over the place.

src/shared/dissect-image.c

@@ -1244,7 +1244,6 @@ int dissected_image_acquire_metadata(DissectedImage *m) {
         _cleanup_free_ char *hostname = NULL;
         unsigned n_meta_initialized = 0, k;
         int fds[2 * _META_MAX], r;
-        siginfo_t si;
 
         BLOCK_SIGNALS(SIGCHLD);
 
@@ -1366,15 +1365,12 @@ int dissected_image_acquire_metadata(DissectedImage *m) {
                 }
         }
 
-        r = wait_for_terminate(child, &si);
+        r = wait_for_terminate_and_check("(sd-dissect)", child, 0);
+        child = 0;
         if (r < 0)
                 goto finish;
-        child = 0;
-
-        if (si.si_code != CLD_EXITED || si.si_status != EXIT_SUCCESS) {
-                r = -EPROTO;
-                goto finish;
-        }
+        if (r != EXIT_SUCCESS)
+                return -EPROTO;
 
         free_and_replace(m->hostname, hostname);
         m->machine_id = machine_id;

src/shared/logs-show.c

@@ -1256,7 +1256,6 @@ static int get_boot_id_for_machine(const char *machine, sd_id128_t *boot_id) {
         _cleanup_close_pair_ int pair[2] = { -1, -1 };
         _cleanup_close_ int pidnsfd = -1, mntnsfd = -1, rootfd = -1;
         pid_t pid, child;
-        siginfo_t si;
         char buf[37];
         ssize_t k;
         int r;
@@ -1308,9 +1307,11 @@ static int get_boot_id_for_machine(const char *machine, sd_id128_t *boot_id) {
 
         pair[1] = safe_close(pair[1]);
 
-        r = wait_for_terminate(child, &si);
-        if (r < 0 || si.si_code != CLD_EXITED || si.si_status != EXIT_SUCCESS)
-                return r < 0 ? r : -EIO;
+        r = wait_for_terminate_and_check("(sd-bootid)", child, 0);
+        if (r < 0)
+                return r;
+        if (r != EXIT_SUCCESS)
+                return -EIO;
 
         k = recv(pair[0], buf, 36, 0);
         if (k != 36)

src/shared/machine-pool.c

@@ -79,7 +79,6 @@ static int setup_machine_raw(uint64_t size, sd_bus_error *error) {
         _cleanup_close_ int fd = -1;
         struct statvfs ss;
         pid_t pid = 0;
-        siginfo_t si;
         int r;
 
         /* We want to be able to make use of btrfs-specific file
@@ -141,24 +140,19 @@ static int setup_machine_raw(uint64_t size, sd_bus_error *error) {
                 _exit(EXIT_FAILURE);
         }
 
-        r = wait_for_terminate(pid, &si);
+        r = wait_for_terminate_and_check("mkfs", pid, 0);
+        pid = 0;
+
         if (r < 0) {
                 sd_bus_error_set_errnof(error, r, "Failed to wait for mkfs.btrfs: %m");
                 goto fail;
         }
-
-        pid = 0;
-
-        if (si.si_code != CLD_EXITED) {
-                r = sd_bus_error_setf(error, SD_BUS_ERROR_FAILED, "mkfs.btrfs died abnormally.");
-                goto fail;
-        }
-        if (si.si_status == 99) {
+        if (r == 99) {
                 r = sd_bus_error_set_errnof(error, ENOENT, "Cannot set up /var/lib/machines, mkfs.btrfs is missing");
                 goto fail;
         }
-        if (si.si_status != 0) {
-                r = sd_bus_error_setf(error, SD_BUS_ERROR_FAILED, "mkfs.btrfs failed with error code %i", si.si_status);
+        if (r != EXIT_SUCCESS) {
+                r = sd_bus_error_setf(error, SD_BUS_ERROR_FAILED, "mkfs.btrfs failed with error code %i", r);
                 goto fail;
         }
 

src/shared/pager.c

@@ -190,7 +190,6 @@ int show_man_page(const char *desc, bool null_stdio) {
         pid_t pid;
         size_t k;
         int r;
-        siginfo_t status;
 
         k = strlen(desc);
 
@@ -218,10 +217,5 @@ int show_man_page(const char *desc, bool null_stdio) {
                 _exit(EXIT_FAILURE);
         }
 
-        r = wait_for_terminate(pid, &status);
-        if (r < 0)
-                return r;
-
-        log_debug("Exit code %i status %i", status.si_code, status.si_status);
-        return status.si_status;
+        return wait_for_terminate_and_check(NULL, pid, 0);
 }