chpstat: Adapt to new JSON Lines text format

util_fmt now provides support for JSON Lines text format. Adapt certain
checks in the code and document the newly supported format in the man
page accordingly.

Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>

zconf/chp/chpstat/chpstat.8

@@ -384,6 +384,17 @@ with an ASCII Record Separator character (0x1e) and suffixed with an ASCII Line
 Feed character (0x0a) in accordance with RFC7464.
 .br
 
+See section "OUTPUT FORMAT" for more details.
+.BR
+.PP
+.IP \(bu 3
+.B jsonl:
+Line-delimited JSON data structures
+
+Data for each iteration is formatted as a single JSON data structure separated
+by an ASCII Line Feed character (0x0a, LF).
+.BR
+
 See section "OUTPUT FORMAT" for more details.
 .br
 .PP
@@ -736,6 +747,12 @@ Subsequent objects each represent channel-path statistics data for one iteration
 .br
 .PP
 
+.SS jsonl
+
+The jsonl output format is a data streaming variation of the JSON output format
+described above with the same properties as the json\-seq output with the
+difference that JSON data is separated only by an ASCII Line Feed character
+(0x0a, LF).
 
 .SH "EXIT CODES"
 .TP

zconf/chp/chpstat/chpstat.c

@@ -1270,7 +1270,7 @@ static void cmd_list(void)
 	if (opts.groups & KEY_GRP_METRICS)
 		update_util_all(true);
 
-	if (opts.fmt != FMT_JSONSEQ)
+	if (!util_fmt_is_json_stream(opts.fmt))
 		util_fmt_obj_start(FMT_LIST, NULL);
 	for (i = 0; opts.forever || i < opts.iterations; i++) {
 		if (i > 0)
@@ -1286,7 +1286,7 @@ static void cmd_list(void)
 		 * via pipes (e.g. for use with grep). */
 		fflush(stdout);
 	}
-	if (opts.fmt != FMT_JSONSEQ)
+	if (!util_fmt_is_json_stream(opts.fmt))
 		util_fmt_obj_end();
 }
 
@@ -1972,7 +1972,7 @@ static void init_fmt(void)
 		flags |= FMT_FILTER;
 	if (!opts.use_prefix)
 		flags |= FMT_NOPREFIX;
-	if (opts.fmt == FMT_JSON || opts.fmt == FMT_JSONSEQ) {
+	if (util_fmt_is_json(opts.fmt)) {
 		/* Ensure correct JSON even if interrupted. */
 		flags |= FMT_HANDLEINT;
 	}