Trivial typo fixes and code refactorings (#5191)

* logind: trivial simplification

free_and_strdup() handles NULL arg, so make use of that.

* boot: fix two typos

* pid1: rewrite check in ignore_proc() to not check condition twice

It's harmless, but it seems nicer to evaluate a condition just a single time.

* core/execute: reformat exec_context_named_iofds() for legibility

* core/execute.c: check asprintf return value in the usual fashion

This is unlikely to fail, but we cannot rely on asprintf return value
on failure, so let's just be correct here.

CID #1368227.

* core/timer: use (void)

CID #1368234.

* journal-file: check asprintf return value in the usual fashion

This is unlikely to fail, but we cannot rely on asprintf return value
on failure, so let's just be correct here.

CID #1368236.

* shared/cgroup-show: use (void)

CID #1368243.

* cryptsetup: do not return uninitialized value on error

CID #1368416.

3 files changed, 55 insertions, 38 deletions

diff --git a/src/core/execute.c b/src/core/execute.c
index d0faba5a85..47cc4311c1 100644
--- a/src/core/execute.c
+++ b/src/core/execute.c
@@ -1685,25 +1685,31 @@ static int setup_private_users(uid_t uid, gid_t gid) {
          * child then writes the UID mapping, under full privileges. The parent waits for the child to finish and
          * continues execution normally. */
 
-        if (uid != 0 && uid_is_valid(uid))
-                asprintf(&uid_map,
-                         "0 0 1\n"                      /* Map root → root */
-                         UID_FMT " " UID_FMT " 1\n",    /* Map $UID → $UID */
-                         uid, uid);
-        else
+        if (uid != 0 && uid_is_valid(uid)) {
+                r = asprintf(&uid_map,
+                             "0 0 1\n"                      /* Map root → root */
+                             UID_FMT " " UID_FMT " 1\n",    /* Map $UID → $UID */
+                             uid, uid);
+                if (r < 0)
+                        return -ENOMEM;
+        } else {
                 uid_map = strdup("0 0 1\n");            /* The case where the above is the same */
-        if (!uid_map)
-                return -ENOMEM;
+                if (!uid_map)
+                        return -ENOMEM;
+        }
 
-        if (gid != 0 && gid_is_valid(gid))
-                asprintf(&gid_map,
-                         "0 0 1\n"                      /* Map root → root */
-                         GID_FMT " " GID_FMT " 1\n",    /* Map $GID → $GID */
-                         gid, gid);
-        else
+        if (gid != 0 && gid_is_valid(gid)) {
+                r = asprintf(&gid_map,
+                             "0 0 1\n"                      /* Map root → root */
+                             GID_FMT " " GID_FMT " 1\n",    /* Map $GID → $GID */
+                             gid, gid);
+                if (r < 0)
+                        return -ENOMEM;
+        } else {
                 gid_map = strdup("0 0 1\n");            /* The case where the above is the same */
-        if (!gid_map)
-                return -ENOMEM;
+                if (!gid_map)
+                        return -ENOMEM;
+        }
 
         /* Create a communication channel so that the parent can tell the child when it finished creating the user
          * namespace. */
@@ -3096,7 +3102,7 @@ const char* exec_context_fdname(const ExecContext *c, int fd_index) {
 
 int exec_context_named_iofds(Unit *unit, const ExecContext *c, const ExecParameters *p, int named_iofds[3]) {
         unsigned i, targets;
-        const char *stdio_fdname[3];
+        const char* stdio_fdname[3];
 
         assert(c);
         assert(p);
@@ -3109,18 +3115,32 @@ int exec_context_named_iofds(Unit *unit, const ExecContext *c, const ExecParamet
                 stdio_fdname[i] = exec_context_fdname(c, i);
 
         for (i = 0; i < p->n_fds && targets > 0; i++)
-                if (named_iofds[STDIN_FILENO] < 0 && c->std_input == EXEC_INPUT_NAMED_FD && stdio_fdname[STDIN_FILENO] && streq(p->fd_names[i], stdio_fdname[STDIN_FILENO])) {
+                if (named_iofds[STDIN_FILENO] < 0 &&
+                    c->std_input == EXEC_INPUT_NAMED_FD &&
+                    stdio_fdname[STDIN_FILENO] &&
+                    streq(p->fd_names[i], stdio_fdname[STDIN_FILENO])) {
+
                         named_iofds[STDIN_FILENO] = p->fds[i];
                         targets--;
-                } else if (named_iofds[STDOUT_FILENO] < 0 && c->std_output == EXEC_OUTPUT_NAMED_FD && stdio_fdname[STDOUT_FILENO] && streq(p->fd_names[i], stdio_fdname[STDOUT_FILENO])) {
+
+                } else if (named_iofds[STDOUT_FILENO] < 0 &&
+                           c->std_output == EXEC_OUTPUT_NAMED_FD &&
+                           stdio_fdname[STDOUT_FILENO] &&
+                           streq(p->fd_names[i], stdio_fdname[STDOUT_FILENO])) {
+
                         named_iofds[STDOUT_FILENO] = p->fds[i];
                         targets--;
-                } else if (named_iofds[STDERR_FILENO] < 0 && c->std_error == EXEC_OUTPUT_NAMED_FD && stdio_fdname[STDERR_FILENO] && streq(p->fd_names[i], stdio_fdname[STDERR_FILENO])) {
+
+                } else if (named_iofds[STDERR_FILENO] < 0 &&
+                           c->std_error == EXEC_OUTPUT_NAMED_FD &&
+                           stdio_fdname[STDERR_FILENO] &&
+                           streq(p->fd_names[i], stdio_fdname[STDERR_FILENO])) {
+
                         named_iofds[STDERR_FILENO] = p->fds[i];
                         targets--;
                 }
 
-        return (targets == 0 ? 0 : -ENOENT);
+        return targets == 0 ? 0 : -ENOENT;
 }
 
 int exec_context_load_environment(Unit *unit, const ExecContext *c, char ***l) {
diff --git a/src/core/killall.c b/src/core/killall.c
index b3aa22adc5..7a9df546ee 100644
--- a/src/core/killall.c
+++ b/src/core/killall.c
@@ -66,29 +66,26 @@ static bool ignore_proc(pid_t pid, bool warn_rootfs) {
         if (count <= 0)
                 return true;
 
-        /* Processes with argv[0][0] = '@' we ignore from the killing
-         * spree.
+        /* Processes with argv[0][0] = '@' we ignore from the killing spree.
          *
          * http://www.freedesktop.org/wiki/Software/systemd/RootStorageDaemons */
-        if (c == '@' && warn_rootfs) {
-                _cleanup_free_ char *comm = NULL;
+        if (c != '@')
+                return false;
 
-                r = pid_from_same_root_fs(pid);
-                if (r < 0)
-                        return true;
+        if (warn_rootfs &&
+            pid_from_same_root_fs(pid) == 0) {
+
+                _cleanup_free_ char *comm = NULL;
 
                 get_process_comm(pid, &comm);
 
-                if (r)
-                        log_notice("Process " PID_FMT " (%s) has been marked to be excluded from killing. It is "
-                                   "running from the root file system, and thus likely to block re-mounting of the "
-                                   "root file system to read-only. Please consider moving it into an initrd file "
-                                   "system instead.", pid, strna(comm));
-                return true;
-        } else if (c == '@')
-                return true;
+                log_notice("Process " PID_FMT " (%s) has been marked to be excluded from killing. It is "
+                           "running from the root file system, and thus likely to block re-mounting of the "
+                           "root file system to read-only. Please consider moving it into an initrd file "
+                           "system instead.", pid, strna(comm));
+        }
 
-        return false;
+        return true;
 }
 
 static void wait_for_children(Set *pids, sigset_t *mask) {
diff --git a/src/core/timer.c b/src/core/timer.c
index 5ee14669d2..d7441d638f 100644
--- a/src/core/timer.c
+++ b/src/core/timer.c
@@ -232,7 +232,7 @@ static void timer_dump(Unit *u, FILE *f, const char *prefix) {
                 if (v->base == TIMER_CALENDAR) {
                         _cleanup_free_ char *p = NULL;
 
-                        calendar_spec_to_string(v->calendar_spec, &p);
+                        (void) calendar_spec_to_string(v->calendar_spec, &p);
 
                         fprintf(f,
                                 "%s%s: %s\n",