[Qemu-devel] [PATCH 32/43] char: made printf always compile in debug output

[Danil Antonov]

>From 9147a39cc2dabe76e7c1b38e801069390d5a3321 Mon Sep 17 00:00:00 2001
From: Danil Antonov <g.danil.a...@gmail.com>
Date: Wed, 29 Mar 2017 12:40:02 +0300
Subject: [PATCH 32/43] char: made printf always compile in debug output

Wrapped printf calls inside debug macros (DPRINTF) in `if` statement.
This will ensure that printf function will always compile even if debug
output is turned off and, in turn, will prevent bitrot of the format
strings.

Signed-off-by: Danil Antonov <g.danil.a...@gmail.com>
---
 hw/char/ipoctal232.c | 24 +++++++++++++-----------
 hw/char/serial.c     | 16 +++++++++-------
 2 files changed, 22 insertions(+), 18 deletions(-)

diff --git a/hw/char/ipoctal232.c b/hw/char/ipoctal232.c
index 93929c2..180d8f7 100644
--- a/hw/char/ipoctal232.c
+++ b/hw/char/ipoctal232.c
@@ -13,14 +13,16 @@
 #include "qemu/bitops.h"
 #include "sysemu/char.h"

-/* #define DEBUG_IPOCTAL */

-#ifdef DEBUG_IPOCTAL
-#define DPRINTF2(fmt, ...) \
-    do { fprintf(stderr, fmt, ## __VA_ARGS__); } while (0)
-#else
-#define DPRINTF2(fmt, ...) do { } while (0)
-#endif
+#ifndef DEBUG_IPOCTAL
+#define DEBUG_IPOCTAL 0
+#endif
+
+#define DPRINTF2(fmt, ...) do {                \
+    if (DEBUG_IPOCTAL) {                       \
+        fprintf(stderr, fmt, ## __VA_ARGS__);  \
+    }                                          \
+} while (0);

 #define DPRINTF(fmt, ...) DPRINTF2("IP-Octal: " fmt, ## __VA_ARGS__)

@@ -504,11 +506,11 @@ static void hostdev_event(void *opaque, int event)
     SCC2698Channel *ch = opaque;
     switch (event) {
     case CHR_EVENT_OPENED:
-        DPRINTF("Device %s opened\n", ch->dev->label);
+        DPRINTF("Device %s opened\n", ch->dev.chr->label);
         break;
     case CHR_EVENT_BREAK: {
         uint8_t zero = 0;
-        DPRINTF("Device %s received break\n", ch->dev->label);
+        DPRINTF("Device %s received break\n", ch->dev.chr->label);

         if (!(ch->sr & SR_BREAK)) {
             IPOctalState *dev = ch->ipoctal;
@@ -528,7 +530,7 @@ static void hostdev_event(void *opaque, int event)
     }
         break;
     default:
-        DPRINTF("Device %s received event %d\n", ch->dev->label, event);
+        DPRINTF("Device %s received event %d\n", ch->dev.chr->label,
event);
     }
 }

@@ -546,7 +548,7 @@ static void ipoctal_realize(DeviceState *dev, Error
**errp)
             qemu_chr_fe_set_handlers(&ch->dev, hostdev_can_receive,
                                      hostdev_receive, hostdev_event,
                                      ch, NULL, true);
-            DPRINTF("Redirecting channel %u to %s\n", i, ch->dev->label);
+            DPRINTF("Redirecting channel %u to %s\n", i,
ch->dev.chr->label);
         } else {
             DPRINTF("Could not redirect channel %u, no chardev set\n", i);
         }
diff --git a/hw/char/serial.c b/hw/char/serial.c
index 03d890c..9421c7a 100644
--- a/hw/char/serial.c
+++ b/hw/char/serial.c
@@ -97,13 +97,15 @@

 #define MAX_XMIT_RETRY      4

-#ifdef DEBUG_SERIAL
-#define DPRINTF(fmt, ...) \
-do { fprintf(stderr, "serial: " fmt , ## __VA_ARGS__); } while (0)
-#else
-#define DPRINTF(fmt, ...) \
-do {} while (0)
-#endif
+#ifndef DEBUG_SERIAL
+#define DEBUG_SERIAL 0
+#endif
+
+#define DPRINTF(fmt, ...) do {                            \
+    if (DEBUG_SERIAL) {                                   \
+        fprintf(stderr, "serial: " fmt , ## __VA_ARGS__); \
+    }                                                     \
+} while (0);

 static void serial_receive1(void *opaque, const uint8_t *buf, int size);
 static void serial_xmit(SerialState *s);
-- 
2.8.0.rc3