perf tools: Fix line number in the config file error message

If we fail to parse the config file within the callback function,
the line number counter 'could be' already on the next line.

This results in wrong line number report like:

  $ cat ~/.perfconfig
  [call-graph]
          sort-key = krava
  $ perf record ls
  Fatal: bad config file line 3 in /home/jolsa/.perfconfig

Fixing this by saving the current line number for this case.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Milian Wolff <mail@milianw.de>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20140923115656.GC2979@krava.brq.redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/config.c

@@ -222,7 +222,8 @@ static int perf_parse_file(config_fn_t fn, void *data)
 	const unsigned char *bomptr = utf8_bom;
 
 	for (;;) {
-		int c = get_next_char();
+		int line, c = get_next_char();
+
 		if (bomptr && *bomptr) {
 			/* We are at the file beginning; skip UTF8-encoded BOM
 			 * if present. Sane editors won't put this in on their
@@ -261,8 +262,16 @@ static int perf_parse_file(config_fn_t fn, void *data)
 		if (!isalpha(c))
 			break;
 		var[baselen] = tolower(c);
-		if (get_value(fn, data, var, baselen+1) < 0)
+
+		/*
+		 * The get_value function might or might not reach the '\n',
+		 * so saving the current line number for error reporting.
+		 */
+		line = config_linenr;
+		if (get_value(fn, data, var, baselen+1) < 0) {
+			config_linenr = line;
 			break;
+		}
 	}
 	die("bad config file line %d in %s", config_linenr, config_file_name);
 }