perf: Use strerror_r instead of strerror

Use strerror_r instead of strerror in error messages for thread-safety.
This also introduce STRERR_BUFSIZE macro for the default size of message
buffer for strerror_r.

Signed-off-by: Masami Hiramatsu <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Cc: Naohiro Aota <[e-mail]>
Cc: Paul Mackerras <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/perf.c

···
 	int status;
 	struct stat st;
 	const char *prefix;
+	char sbuf[STRERR_BUFSIZE];
 
 	prefix = NULL;
 	if (p->option & RUN_SETUP)
···
 	status = 1;
 	/* Check for ENOSPC and EIO errors.. */
 	if (fflush(stdout)) {
-		fprintf(stderr, "write failure on standard output: %s", strerror(errno));
+		fprintf(stderr, "write failure on standard output: %s",
+			strerror_r(errno, sbuf, sizeof(sbuf)));
 		goto out;
 	}
 	if (ferror(stdout)) {
···
 		goto out;
 	}
 	if (fclose(stdout)) {
-		fprintf(stderr, "close failed on standard output: %s", strerror(errno));
+		fprintf(stderr, "close failed on standard output: %s",
+			strerror_r(errno, sbuf, sizeof(sbuf)));
 		goto out;
 	}
 	status = 0;
···
 int main(int argc, const char **argv)
 {
 	const char *cmd;
+	char sbuf[STRERR_BUFSIZE];
 
 	/* The page_size is placed in util object. */
 	page_size = sysconf(_SC_PAGE_SIZE);
···
 	}
 
 	fprintf(stderr, "Failed to run command '%s': %s\n",
-		cmd, strerror(errno));
+		cmd, strerror_r(errno, sbuf, sizeof(sbuf)));
 out:
 	return 1;
 }

tools/perf/util/debug.h

···
 #define __PERF_DEBUG_H
 
 #include <stdbool.h>
+#include <string.h>
 #include "event.h"
 #include "../ui/helpline.h"
 #include "../ui/progress.h"
···
 
 #define pr_oe_time(t, fmt, ...)  pr_time_N(1, debug_ordered_events, t, pr_fmt(fmt), ##__VA_ARGS__)
 #define pr_oe_time2(t, fmt, ...) pr_time_N(2, debug_ordered_events, t, pr_fmt(fmt), ##__VA_ARGS__)
+
+#define STRERR_BUFSIZE	128	/* For the buffer size of strerror_r */
 
 int dump_printf(const char *fmt, ...) __attribute__((format(printf, 1, 2)));
 void trace_event(union perf_event *event);