log.h: new log_oom() -> int -ENOMEM, use it

also a number of minor fixups and bug fixes: spelling, oom errors
that didn't print errors, not properly forwarding error codes,
few more consistency issues, et cetera

src/shared/ask-password-api.c

@@ -281,8 +281,7 @@ static int create_socket(char **name) {
         }
 
         if (!(c = strdup(sa.un.sun_path))) {
-                r = -ENOMEM;
-                log_error("Out of memory.");
+                r = log_oom();
                 goto fail;
         }
 

src/shared/dbus-common.c

@@ -1161,7 +1161,7 @@ void bus_async_unregister_and_exit(DBusConnection *bus, const char *name) {
         return;
 
 oom:
-        log_error("Out of memory.");
+        log_oom();
 
         if (pending) {
                 dbus_pending_call_cancel(pending);

src/shared/log.h

@@ -24,6 +24,7 @@
 #include <syslog.h>
 #include <stdbool.h>
 #include <stdarg.h>
+#include <errno.h>
 
 #include "macro.h"
 
@@ -102,6 +103,11 @@ int log_dump_internal(
 #define log_warning(...) log_meta(LOG_WARNING, __FILE__, __LINE__, __func__, __VA_ARGS__)
 #define log_error(...)   log_meta(LOG_ERR,     __FILE__, __LINE__, __func__, __VA_ARGS__)
 
+static inline int log_oom(void) {
+       log_error("Out of memory.");
+       return -ENOMEM;
+}
+
 /* This modifies the buffer passed! */
 #define log_dump(level, buffer) log_dump_internal(level, __FILE__, __LINE__, __func__, buffer)
 

src/shared/logs-show.c

@@ -52,10 +52,8 @@ static int parse_field(const void *data, size_t length, const char *field, char
         buf = malloc(nl+1);
         memcpy(buf, (const char*) data + fl, nl);
         ((char*)buf)[nl] = 0;
-        if (!buf) {
-                log_error("Out of memory.");
-                return -ENOMEM;
-        }
+        if (!buf)
+                return log_oom();
 
         free(*target);
         *target = buf;

src/shared/util.c

@@ -909,8 +909,7 @@ int load_env_file(
                         continue;
 
                 if (!(u = normalize_env_assignment(p))) {
-                        log_error("Out of memory.");
-                        r = -ENOMEM;
+                        r = log_oom();
                         goto finish;
                 }
 
@@ -918,8 +917,7 @@ int load_env_file(
                 free(u);
 
                 if (!t) {
-                        log_error("Out of memory.");
-                        r = -ENOMEM;
+                        r = log_oom();
                         goto finish;
                 }
 
@@ -4278,7 +4276,7 @@ void execute_directory(const char *directory, DIR *d, char *argv[]) {
                         continue;
 
                 if (asprintf(&path, "%s/%s", directory, de->d_name) < 0) {
-                        log_error("Out of memory.");
+                        log_oom();
                         continue;
                 }