perf trace: Add alignment spaces after the closing parens

To use strace's style, helping in comparing the output of 'perf trace'
with the one from 'strace', to help in upcoming regression tests.

Cc: Adrian Hunter <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Cc: Luis Cláudio Gonçalves <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Cc: Wang Nan <[e-mail]>
Link: https://lkml.kernel.org/n/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/builtin-trace.c

···
 		return 0;
 
 	printed  = trace__fprintf_entry_head(trace, trace->current, 0, false, ttrace->entry_time, trace->output);
-	printed += fprintf(trace->output, "%-*s) ...\n", trace->args_alignment, ttrace->entry_str);
+	printed += fprintf(trace->output, ")%-*s ...\n", trace->args_alignment, ttrace->entry_str);
 	ttrace->entry_pending = false;
 
 	++trace->nr_events_printed;
···
 {
 	char *msg;
 	void *args;
-	size_t printed = 0;
+	int printed = 0;
 	struct thread *thread;
 	int id = perf_evsel__sc_tp_uint(evsel, id, sample), err = -1;
 	int augmented_args_size = 0;
···
 
 	if (sc->is_exit) {
 		if (!(trace->duration_filter || trace->summary_only || trace->failure_only || trace->min_stack)) {
+			int alignment = 0;
+
 			trace__fprintf_entry_head(trace, thread, 0, false, ttrace->entry_time, trace->output);
-			fprintf(trace->output, "%-*s)\n", trace->args_alignment, ttrace->entry_str);
+			printed = fprintf(trace->output, "%s)", ttrace->entry_str);
+			if (trace->args_alignment > printed)
+				alignment = trace->args_alignment - printed;
+			fprintf(trace->output, "%*s= ?\n", alignment, " ");
 		}
 	} else {
 		ttrace->entry_pending = true;
···
 	u64 duration = 0;
 	bool duration_calculated = false;
 	struct thread *thread;
-	int id = perf_evsel__sc_tp_uint(evsel, id, sample), err = -1, callchain_ret = 0;
+	int id = perf_evsel__sc_tp_uint(evsel, id, sample), err = -1, callchain_ret = 0, printed = 0;
+	int alignment = trace->args_alignment;
 	struct syscall *sc = trace__syscall_info(trace, evsel, id);
 	struct thread_trace *ttrace;
 
···
 	trace__fprintf_entry_head(trace, thread, duration, duration_calculated, ttrace->entry_time, trace->output);
 
 	if (ttrace->entry_pending) {
-		fprintf(trace->output, "%-*s", trace->args_alignment, ttrace->entry_str);
+		printed = fprintf(trace->output, "%s", ttrace->entry_str);
 	} else {
 		fprintf(trace->output, " ... [");
 		color_fprintf(trace->output, PERF_COLOR_YELLOW, "continued");
 		fprintf(trace->output, "]: %s()", sc->name);
 	}
 
+	printed++; /* the closing ')' */
+
+	if (alignment > printed)
+		alignment -= printed;
+	else
+		alignment = 0;
+
+	fprintf(trace->output, ")%*s= ", alignment, " ");
+
 	if (sc->fmt == NULL) {
 		if (ret < 0)
 			goto errno_print;
 signed_print:
-		fprintf(trace->output, ") = %ld", ret);
+		fprintf(trace->output, "%ld", ret);
 	} else if (ret < 0) {
 errno_print: {
 		char bf[STRERR_BUFSIZE];
 		const char *emsg = str_error_r(-ret, bf, sizeof(bf)),
 			   *e = errno_to_name(evsel, -ret);
 
-		fprintf(trace->output, ") = -1 %s %s", e, emsg);
+		fprintf(trace->output, "-1 %s %s", e, emsg);
 	}
 	} else if (ret == 0 && sc->fmt->timeout)
-		fprintf(trace->output, ") = 0 Timeout");
+		fprintf(trace->output, "0 Timeout");
 	else if (ttrace->ret_scnprintf) {
 		char bf[1024];
 		struct syscall_arg arg = {
···
 		};
 		ttrace->ret_scnprintf(bf, sizeof(bf), &arg);
 		ttrace->ret_scnprintf = NULL;
-		fprintf(trace->output, ") = %s", bf);
+		fprintf(trace->output, "%s", bf);
 	} else if (sc->fmt->hexret)
-		fprintf(trace->output, ") = %#lx", ret);
+		fprintf(trace->output, "%#lx", ret);
 	else if (sc->fmt->errpid) {
 		struct thread *child = machine__find_thread(trace->host, ret, ret);
 
 		if (child != NULL) {
-			fprintf(trace->output, ") = %ld", ret);
+			fprintf(trace->output, "%ld", ret);
 			if (child->comm_set)
 				fprintf(trace->output, " (%s)", thread__comm_str(child));
 			thread__put(child);