From: WanBingjiang <wanbingjiang@webray.com.cn>
Date: Mon, 23 Feb 2026 08:32:48 +0000 (+0800)
Subject: jsonwrt: simplify ul_jsonwrt_empty() and add comments for COMPACT format
X-Git-Tag: v2.43-devel~50^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c0c03f6b80471eb51149eb6ecb90b3c70f0a5f70;p=thirdparty%2Futil-linux.git

jsonwrt: simplify ul_jsonwrt_empty() and add comments for COMPACT format

Consolidate duplicated LINE/COMPACT branches in ul_jsonwrt_empty()
into a single else-branch, since they produce identical output.

Add comments explaining the indent depth checks in ul_jsonwrt_open()
and ul_jsonwrt_close() for COMPACT format.
---

diff --git a/lib/jsonwrt.c b/lib/jsonwrt.c
index 454cfb6b2..57f5703da 100644
--- a/lib/jsonwrt.c
+++ b/lib/jsonwrt.c
@@ -159,6 +159,8 @@ void ul_jsonwrt_open(struct ul_jsonwrt *fmt, const char *name, int type)
 		if (fmt->json_format == UL_JSON_LINE)
 			s = "{";
 		else if (fmt->json_format == UL_JSON_COMPACT) {
+			/* At nesting depth 2, put the object opens on a new line
+			 * for readability; otherwise keep fully compact (no newline). */
 			if (fmt->indent == 2)
 				s = name ? ":{" : "\n{";
 			else
@@ -197,28 +199,22 @@ void ul_jsonwrt_empty(struct ul_jsonwrt *fmt, const char *name, int type)
 
 	switch (type) {
 	case UL_JSON_OBJECT:
-		if (fmt->json_format == UL_JSON_LINE)
-			s = name ? ":{}" : "{}";
-		else if (fmt->json_format == UL_JSON_COMPACT)
-			s = name ? ":{}" : "{}";
-		else
+		if (fmt->json_format == UL_JSON_PRETTY)
 			s = name ? ": {}" : "{}";
+		else
+			s = name ? ":{}" : "{}";
 		break;
 	case UL_JSON_ARRAY:
-		if (fmt->json_format == UL_JSON_LINE)
-			s = name ? ":[]" : "[]";
-		else if (fmt->json_format == UL_JSON_COMPACT)
-			s = name ? ":[]" : "[]";
-		else
+		if (fmt->json_format == UL_JSON_PRETTY)
 			s = name ? ": []" : "[]";
+		else
+			s = name ? ":[]" : "[]";
 		break;
 	case UL_JSON_VALUE:
-		if (fmt->json_format == UL_JSON_LINE)
-			s = name ? ":null" : "null";
-		else if (fmt->json_format == UL_JSON_COMPACT)
-			s = name ? ":null" : "null";
-		else
+		if (fmt->json_format == UL_JSON_PRETTY)
 			s = name ? ": null" : "null";
+		else
+			s = name ? ":null" : "null";
 		break;
 	}
 	fputs(s, fmt->out);
@@ -248,6 +244,8 @@ void ul_jsonwrt_close(struct ul_jsonwrt *fmt, int type)
 		return;
 	}
 
+	/* In COMPACT, when closing a direct child of root (indent==1),
+	 * insert a newline so the closing bracket starts on its own line. */
 	if (fmt->json_format == UL_JSON_COMPACT && fmt->indent == 1)
 		fputc('\n', fmt->out);
 
diff --git a/misc-utils/blkid.c b/misc-utils/blkid.c
index 8c1f4fc61..29f2046f7 100644
--- a/misc-utils/blkid.c
+++ b/misc-utils/blkid.c
@@ -925,7 +925,7 @@ int main(int argc, char **argv)
 		       "search type specified using -t"));
 
 	if (!ctl.eval && ctl.output & OUTPUT_JSON) {
-		ul_jsonwrt_init(ctl.json_fmt, stdout, 0);
+		ul_jsonwrt_init(ctl.json_fmt, stdout, 0, UL_JSON_PRETTY);
 		ul_jsonwrt_root_open(ctl.json_fmt);
 		ul_jsonwrt_array_open(ctl.json_fmt, "blkid");
 	}