From 0c7b7a19e5a3c23fbb789238dcc4d43cd55387a0 Mon Sep 17 00:00:00 2001
From: Brian Wellington <source@isc.org>
Date: Mon, 19 Jun 2000 18:02:32 +0000
Subject: [PATCH] Use GCC's format attribute for better error checking when
 possible.

---
 lib/isc/include/isc/log.h | 29 ++++++++++++++++++++++-------
 1 file changed, 22 insertions(+), 7 deletions(-)

diff --git a/lib/isc/include/isc/log.h b/lib/isc/include/isc/log.h
index 59ec435efd..7865eb5cc7 100644
--- a/lib/isc/include/isc/log.h
+++ b/lib/isc/include/isc/log.h
@@ -15,7 +15,7 @@
  * SOFTWARE.
  */
 
-/* $Id: log.h,v 1.22 2000/06/01 17:20:40 tale Exp $ */
+/* $Id: log.h,v 1.23 2000/06/19 18:02:32 bwelling Exp $ */
 
 #ifndef ISC_LOG_H
 #define ISC_LOG_H 1
@@ -29,6 +29,17 @@
 
 ISC_LANG_BEGINDECLS
 
+/*
+ * fmt is the location of the format string parameter
+ * args is the location of the first argument (or 0 for no argument checking)
+ * Note: the first parameter is 1, not 0
+ */
+#ifdef __GNUC__
+#define ISC_FORMAT_PRINTF(fmt, args) __attribute__((format (printf, fmt, args)))
+#else
+#define ISC_FORMAT_PRINTF(fmt, args)
+#endif
+
 /*
  * Severity levels, patterned after Unix's syslog levels.
  *
@@ -498,7 +509,8 @@ isc_log_usechannel(isc_logconfig_t *lcfg, const char *name,
 
 void
 isc_log_write(isc_log_t *lctx, isc_logcategory_t *category,
-	      isc_logmodule_t *module, int level, const char *format, ...);
+	      isc_logmodule_t *module, int level, const char *format, ...)
+ISC_FORMAT_PRINTF(5, 6);
 /*
  * Write a message to the log channels.
  *
@@ -517,7 +529,7 @@ isc_log_write(isc_log_t *lctx, isc_logcategory_t *category,
  *	range of known ids, as estabished by isc_log_registercategories()
  *	and isc_log_registermodules().
  *
- *	level != ISC_LOG_DYNAMiC.  ISC_LOG_DYNAMIC is used only to define
+ *	level != ISC_LOG_DYNAMIC.  ISC_LOG_DYNAMIC is used only to define
  *	channels, and explicit debugging level must be identified for
  *	isc_log_write() via ISC_LOG_DEBUG(level).
  *
@@ -535,7 +547,8 @@ isc_log_write(isc_log_t *lctx, isc_logcategory_t *category,
 void
 isc_log_vwrite(isc_log_t *lctx, isc_logcategory_t *category,
 	       isc_logmodule_t *module, int level, const char *format,
-	       va_list args);
+	       va_list args)
+ISC_FORMAT_PRINTF(5, 0);
 /*
  * Write a message to the log channels.
  *
@@ -554,7 +567,7 @@ isc_log_vwrite(isc_log_t *lctx, isc_logcategory_t *category,
  *	range of known ids, as estabished by isc_log_registercategories()
  *	and isc_log_registermodules().
  *
- *	level != ISC_LOG_DYNAMiC.  ISC_LOG_DYNAMIC is used only to define
+ *	level != ISC_LOG_DYNAMIC.  ISC_LOG_DYNAMIC is used only to define
  *	channels, and explicit debugging level must be identified for
  *	isc_log_write() via ISC_LOG_DEBUG(level).
  *
@@ -571,7 +584,8 @@ isc_log_vwrite(isc_log_t *lctx, isc_logcategory_t *category,
 
 void
 isc_log_write1(isc_log_t *lctx, isc_logcategory_t *category,
-	      isc_logmodule_t *module, int level, const char *format, ...);
+	      isc_logmodule_t *module, int level, const char *format, ...)
+ISC_FORMAT_PRINTF(5, 6);
 /*
  * Write a message to the log channels, pruning duplicates that occur within
  * a configurable amount of seconds (see isc_log_[sg]etduplicateinterval).
@@ -581,7 +595,8 @@ isc_log_write1(isc_log_t *lctx, isc_logcategory_t *category,
 void
 isc_log_vwrite1(isc_log_t *lctx, isc_logcategory_t *category,
 	       isc_logmodule_t *module, int level, const char *format,
-	       va_list args);
+	       va_list args)
+ISC_FORMAT_PRINTF(5, 0);
 /*
  * Write a message to the log channels, pruning duplicates that occur within
  * a configurable amount of seconds (see isc_log_[sg]etduplicateinterval).