sd-json,tree-wide: add sd_json_format_enabled() and use it everwhere

We often used a pattern like if (!FLAGS_SET(flags, SD_JSON_FORMAT_OFF)),
which is rather verbose and also contains a double negative, which we try
to avoid. Add a little helper to avoid an explicit bit check.

This change clarifies an aditional thing: in some cases we treated
SD_JSON_FORMAT_OFF as a flag (flags & SD_JSON_FORMAT_OFF), while in other cases
we treated it as an independent enum value (flags == SD_JSON_FORMAT_OFF).
In the first form, flags like SD_JSON_FORMAT_SSE do _not_ turn the json
output on, while in the second form they do. Let's use the first form
everywhere.

No functional change intended.

Initially I wasn't sure if this helper should be made public or just internal,
but it seems such a common pattern that if we expose the flags, we might just
as well expose it too, to make life easier for any consumers.

2 files changed, 2 insertions, 2 deletions

diff --git a/src/shared/bootspec.c b/src/shared/bootspec.c
index 87aa11ccdf..4c0195a41e 100644
--- a/src/shared/bootspec.c
+++ b/src/shared/bootspec.c
@@ -1936,7 +1936,7 @@ int show_boot_entries(const BootConfig *config, sd_json_format_flags_t json_form
 
         assert(config);
 
-        if (!FLAGS_SET(json_format, SD_JSON_FORMAT_OFF)) {
+        if (sd_json_format_enabled(json_format)) {
                 _cleanup_(sd_json_variant_unrefp) sd_json_variant *array = NULL;
 
                 for (size_t i = 0; i < config->n_entries; i++) {
diff --git a/src/shared/format-table.c b/src/shared/format-table.c
index f5ef7175a3..5f05247438 100644
--- a/src/shared/format-table.c
+++ b/src/shared/format-table.c
@@ -3124,7 +3124,7 @@ int table_print_json(Table *t, FILE *f, sd_json_format_flags_t flags) {
 
         assert(t);
 
-        if (flags & SD_JSON_FORMAT_OFF) /* If JSON output is turned off, use regular output */
+        if (!sd_json_format_enabled(flags)) /* If JSON output is turned off, use regular output */
                 return table_print(t, f);
 
         if (!f)