x86emu: Teach the debug code about varargs

With -Wformat-nonliteral and a debug build you'd get yelled at here:

../hw/xfree86/x86emu/x86emu/debug.h:188:9: warning: format not a string literal, argument types not checked [-Wformat-nonliteral]

To fix this, rewrite the printf code to actually use varargs and the
appropriate format attribute. All callers of DECODE_PRINTF() pass a
string with no % specifiers, so we pass that as the argument to
printf("%s"). For DECODE_PRINTF2() we just pass the args through.

Signed-off-by: Adam Jackson <ajax@redhat.com>
Reviewed-by: Eric Anholt <eric@anholt.net>

2 files changed, 9 insertions, 14 deletions

diff --git a/hw/xfree86/x86emu/debug.c b/hw/xfree86/x86emu/debug.c
index 72a06ffb8..576ace55e 100644
--- a/hw/xfree86/x86emu/debug.c
+++ b/hw/xfree86/x86emu/debug.c
@@ -40,8 +40,8 @@
 #include "x86emu/x86emui.h"
 #include <stdio.h>
 #include <string.h>
-#ifndef NO_SYS_HEADERS
 #include <stdarg.h>
+#ifndef NO_SYS_HEADERS
 #include <stdlib.h>
 #endif
 
@@ -174,18 +174,14 @@ x86emu_inc_decoded_inst_len(int x)
 }
 
 void
-x86emu_decode_printf(const char *x)
-{
-    sprintf(M.x86.decoded_buf + M.x86.enc_str_pos, "%s", x);
-    M.x86.enc_str_pos += strlen(x);
-}
-
-void
-x86emu_decode_printf2(const char *x, int y)
+x86emu_decode_printf(const char *x, ...)
 {
+    va_list ap;
     char temp[100];
 
-    snprintf(temp, sizeof(temp), x, y);
+    va_start(ap, x);
+    vsnprintf(temp, sizeof(temp), x, ap);
+    va_end(ap);
     sprintf(M.x86.decoded_buf + M.x86.enc_str_pos, "%s", temp);
     M.x86.enc_str_pos += strlen(temp);
 }
diff --git a/hw/xfree86/x86emu/x86emu/debug.h b/hw/xfree86/x86emu/x86emu/debug.h
index 385b804dd..1f04b7b65 100644
--- a/hw/xfree86/x86emu/x86emu/debug.h
+++ b/hw/xfree86/x86emu/x86emu/debug.h
@@ -102,9 +102,9 @@
 #ifdef DEBUG
 
 #define DECODE_PRINTF(x)     	if (DEBUG_DECODE()) \
-									x86emu_decode_printf(x)
+									x86emu_decode_printf("%s",x)
 #define DECODE_PRINTF2(x,y)  	if (DEBUG_DECODE()) \
-									x86emu_decode_printf2(x,y)
+									x86emu_decode_printf(x,y)
 
 /*
  * The following allow us to look at the bytes of an instruction.  The
@@ -189,8 +189,7 @@ extern "C" {                    /* Use "C" linkage when in C++ mode */
 #endif
 
     extern void x86emu_inc_decoded_inst_len(int x);
-    extern void x86emu_decode_printf(const char *x);
-    extern void x86emu_decode_printf2(const char *x, int y);
+    extern void x86emu_decode_printf(const char *x, ...) _X_ATTRIBUTE_PRINTF(1,2);
     extern void x86emu_just_disassemble(void);
     extern void x86emu_single_step(void);
     extern void x86emu_end_instr(void);