Fix write-only use of a few variables

Since the invention of read-only memory, write-only memory has been
considered deprecated. Where appropriate, either make use of the
value, or avoid writing it, to make it clear that it is not used.

10 files changed, 27 insertions, 31 deletions

diff --git a/src/analyze/systemd-analyze.c b/src/analyze/systemd-analyze.c
index a4f15eb646..26769d6c37 100644
--- a/src/analyze/systemd-analyze.c
+++ b/src/analyze/systemd-analyze.c
@@ -384,9 +384,9 @@ static int pretty_boot_time(DBusConnection *bus, char **_buf) {
 
         size = strpcpyf(&ptr, size, "%s (userspace) ", format_timespan(ts, sizeof(ts), t->finish_time - t->userspace_time, USEC_PER_MSEC));
         if (t->kernel_time > 0)
-                size = strpcpyf(&ptr, size, "= %s", format_timespan(ts, sizeof(ts), t->firmware_time + t->finish_time, USEC_PER_MSEC));
+                strpcpyf(&ptr, size, "= %s", format_timespan(ts, sizeof(ts), t->firmware_time + t->finish_time, USEC_PER_MSEC));
         else
-                size = strpcpyf(&ptr, size, "= %s", format_timespan(ts, sizeof(ts), t->finish_time - t->userspace_time, USEC_PER_MSEC));
+                strpcpyf(&ptr, size, "= %s", format_timespan(ts, sizeof(ts), t->finish_time - t->userspace_time, USEC_PER_MSEC));
 
         ptr = strdup(buf);
         if (!ptr)
@@ -818,18 +818,18 @@ static int list_dependencies_one(DBusConnection *bus, const char *name, unsigned
                 if (strv_contains(*units, *c)) {
                         r = list_dependencies_print("...", level + 1, (branches << 1) | (to_print ? 1 : 0),
                                                     true, NULL, boot);
+                        if (r < 0)
+                                return r;
                         continue;
                 }
 
                 r = list_dependencies_one(bus, *c, level + 1, units,
                                           (branches << 1) | (to_print ? 1 : 0));
-                if(r < 0)
+                if (r < 0)
                         return r;
 
-
-                if(!to_print)
+                if (!to_print)
                         break;
-
         }
         return 0;
 }
diff --git a/src/bootchart/bootchart.c b/src/bootchart/bootchart.c
index 14ccd3efe5..edbd3815cd 100644
--- a/src/bootchart/bootchart.c
+++ b/src/bootchart/bootchart.c
@@ -254,7 +254,7 @@ static void do_journal_append(char *file)
 
         p = malloc(9 + BOOTCHART_MAX);
         if (!p) {
-                r = log_oom();
+                log_oom();
                 return;
         }
 
diff --git a/src/bootchart/svg.c b/src/bootchart/svg.c
index 5eee2d1987..7ac0138a2b 100644
--- a/src/bootchart/svg.c
+++ b/src/bootchart/svg.c
@@ -420,13 +420,10 @@ static void svg_pss_graph(void) {
         i = 1;
         LIST_FOREACH_BEFORE(link, sampledata, head) {
                 int bottom;
-                int top;
+                int top = 0;
                 struct ps_sched_struct *prev_sample;
                 struct ps_sched_struct *cross_place;
 
-                bottom = 0;
-                top = 0;
-
                 /* put all the small pss blocks into the bottom */
                 ps = ps_first->next_ps;
                 while (ps->next_ps) {
@@ -533,8 +530,8 @@ static void svg_io_bi_bar(void) {
         int max_here = 0;
         int i;
         int k;
-        struct list_sample_data *start_sampledata = sampledata;
-        struct list_sample_data *stop_sampledata = sampledata;
+        struct list_sample_data *start_sampledata;
+        struct list_sample_data *stop_sampledata;
 
         svg("<!-- IO utilization graph - In -->\n");
 
@@ -599,10 +596,7 @@ static void svg_io_bi_bar(void) {
                 int stop;
                 int diff;
                 double tot;
-                double pbi;
-
-                tot = 0;
-                pbi = 0;
+                double pbi = 0;
 
                 start = MAX(i - ((range / 2) - 1), 0);
                 stop = MIN(i + (range / 2), samples);
@@ -647,8 +641,8 @@ static void svg_io_bo_bar(void) {
         int max_here = 0;
         int i;
         int k;
-        struct list_sample_data *start_sampledata = sampledata;
-        struct list_sample_data *stop_sampledata = sampledata;
+        struct list_sample_data *start_sampledata;
+        struct list_sample_data *stop_sampledata;
 
         svg("<!-- IO utilization graph - out -->\n");
 
diff --git a/src/hostname/hostnamectl.c b/src/hostname/hostnamectl.c
index 66015c2f4c..c6d72b5417 100644
--- a/src/hostname/hostnamectl.c
+++ b/src/hostname/hostnamectl.c
@@ -110,6 +110,8 @@ static void print_status_info(StatusInfo *i) {
                            "PRETTY_NAME", &pretty_name,
                            "CPE_NAME", &cpe_name,
                            NULL);
+        if (r < 0)
+                log_warning("Failed to read /etc/os-release: %s", strerror(-r));
 
         if (!isempty(pretty_name))
                 printf("  Operating System: %s\n", pretty_name);
diff --git a/src/journal/coredump.c b/src/journal/coredump.c
index 68c353fe83..733373b307 100644
--- a/src/journal/coredump.c
+++ b/src/journal/coredump.c
@@ -240,7 +240,7 @@ int main(int argc, char* argv[]) {
         coredump_bufsize = COREDUMP_MIN_START;
         coredump_data = malloc(coredump_bufsize);
         if (!coredump_data) {
-                r = log_oom();
+                log_warning("Failed to allocate memory for core, core will not be stored.");
                 goto finalize;
         }
 
@@ -251,7 +251,7 @@ int main(int argc, char* argv[]) {
                 n = loop_read(STDIN_FILENO, coredump_data + coredump_size,
                               coredump_bufsize - coredump_size, false);
                 if (n < 0) {
-                        log_error("Failed to read core dump data: %s", strerror(-n));
+                        log_error("Failed to read core data: %s", strerror(-n));
                         r = (int) n;
                         goto finish;
                 } else if (n == 0)
@@ -259,13 +259,13 @@ int main(int argc, char* argv[]) {
 
                 coredump_size += n;
 
-                if(coredump_size > COREDUMP_MAX) {
-                        log_error("Coredump too large, ignoring");
+                if (coredump_size > COREDUMP_MAX) {
+                        log_error("Core too large, core will not be stored.");
                         goto finalize;
                 }
 
                 if (!GREEDY_REALLOC(coredump_data, coredump_bufsize, coredump_size + 1)) {
-                        r = log_oom();
+                        log_warning("Failed to allocate memory for core, core will not be stored.");
                         goto finalize;
                 }
         }
@@ -277,7 +277,7 @@ int main(int argc, char* argv[]) {
 finalize:
         r = sd_journal_sendv(iovec, j);
         if (r < 0)
-                log_error("Failed to send coredump: %s", strerror(-r));
+                log_error("Failed to log coredump: %s", strerror(-r));
 
 finish:
         return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
diff --git a/src/libsystemd-bus/test-bus-memfd.c b/src/libsystemd-bus/test-bus-memfd.c
index 05ef555f0d..b9d6a250c3 100644
--- a/src/libsystemd-bus/test-bus-memfd.c
+++ b/src/libsystemd-bus/test-bus-memfd.c
@@ -102,7 +102,7 @@ int main(int argc, char *argv[]) {
 
         /* we did truncate it to 6 */
         r = sd_memfd_get_size(m, &sz);
-        assert_se(sz == 6);
+        assert_se(r >= 0 && sz == 6);
 
         /* map it, check content */
         r = sd_memfd_map(m, 0, 12, (void **)&s);
diff --git a/src/login/logind-dbus.c b/src/login/logind-dbus.c
index bb85c7d4af..890c5c6b1d 100644
--- a/src/login/logind-dbus.c
+++ b/src/login/logind-dbus.c
@@ -484,7 +484,7 @@ static int bus_manager_create_session(Manager *m, DBusMessage *message) {
                         return -EINVAL;
         }
 
-        r = manager_get_session_by_pid(m, leader, &session);
+        manager_get_session_by_pid(m, leader, &session);
         if (session) {
                 _cleanup_dbus_message_unref_ DBusMessage *reply = NULL;
                 _cleanup_free_ char *path = NULL;
diff --git a/src/systemctl/systemctl.c b/src/systemctl/systemctl.c
index 036828b5dd..a8a86edd1f 100644
--- a/src/systemctl/systemctl.c
+++ b/src/systemctl/systemctl.c
@@ -748,7 +748,7 @@ static int list_sockets(DBusConnection *bus, char **args) {
         }
         free(socket_infos);
 
-        return 0;
+        return r;
 }
 
 static int compare_unit_file_list(const void *a, const void *b) {
diff --git a/src/test/test-libudev.c b/src/test/test-libudev.c
index 716767ba5f..f79d20cbfb 100644
--- a/src/test/test-libudev.c
+++ b/src/test/test-libudev.c
@@ -429,7 +429,7 @@ static int test_enumerate(struct udev *udev, const char *subsystem)
         return 0;
 }
 
-static int test_hwdb(struct udev *udev, const char *modalias) {
+static void test_hwdb(struct udev *udev, const char *modalias) {
         struct udev_hwdb *hwdb;
         struct udev_list_entry *entry;
 
@@ -440,7 +440,7 @@ static int test_hwdb(struct udev *udev, const char *modalias) {
         printf("\n");
 
         hwdb = udev_hwdb_unref(hwdb);
-        return 0;
+        assert(hwdb == NULL);
 }
 
 int main(int argc, char *argv[])
diff --git a/src/udev/udevadm-hwdb.c b/src/udev/udevadm-hwdb.c
index d9dc73bfc1..d0cce84859 100644
--- a/src/udev/udevadm-hwdb.c
+++ b/src/udev/udevadm-hwdb.c
@@ -648,7 +648,7 @@ static int adm_hwdb(struct udev *udev, int argc, char *argv[]) {
 
                         udev_list_entry_foreach(entry, udev_hwdb_get_properties_list_entry(hwdb, test, 0))
                                 printf("%s=%s\n", udev_list_entry_get_name(entry), udev_list_entry_get_value(entry));
-                        hwdb = udev_hwdb_unref(hwdb);
+                        udev_hwdb_unref(hwdb);
                 }
         }
 out: