Merge pull request #19 from tpiekarski/feature/debug-switch

Merging feature/debug-switch, resolves #5

Makefile

@@ -22,11 +22,15 @@
 # 
 #
 
-SHELL:=/bin/bash
+SELF_DIR := $(dir $(lastword $(MAKEFILE_LIST)))
+include $(SELF_DIR)/debug.mk
+
 BUILD=/lib/modules/$(shell uname -r)/build
-ccflags-y := -Wall
+SHELL:=/bin/bash
+ccflags-y := -std=gnu99 -Wall -Wno-declaration-after-statement $(DEBUG_FLAGS)
 obj-m += pretty_printk_demo.o
 
+
 all: license clean demo
 
 demo:

README.md

@@ -22,14 +22,14 @@ inside the code and on the other one it should increase readability when running
 // [...]
 
 pp_warn("Shortcut for severity level and flushing '\n' character");
-pp_debug("Extended metadata like function name, file name and line number while printk-ing");
+pp_debug("Extended metadata while printk-ing with debug=1 or PP_DEBUG");
 
 // [...]
 ```
 
 ```sh
-[ 3009.387138] pretty_printk_demo: "Shortcut for severity level and flushing '\n' character"
-[ 3009.387139] pretty_printk_demo (pretty_printk_demo_init @ pretty_printk_demo.c, 58): "Extended metadata like function name, file name and line number while printk-ing"
+[ 8204.477771] pretty_printk_demo: "Shortcut for severity level and flushing '\n' character"
+[ 8204.477773] pretty_printk_demo (pretty_printk_demo_init @ pretty_printk_demo.c, 62): "Extended metadata while printk-ing with debug=1 or PP_DEBUG"
 ```
 
 For testing, playing and looking at the features the repository provides a demo module *pretty_printk_demo* to

debug.mk

@@ -0,0 +1,32 @@
+#
+# pretty-printk::Debug Makefile Include
+# <https://github.com/tpiekarski/pretty-printk>
+# ---
+# Copyright 2020 Thomas Piekarski <[email protected]>
+#
+# This file is part of pretty-printk - a pretty way to print to 
+# the Linux Kernel Ring Buffer
+# 
+# pretty-printk is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 2 of the License, or
+# (at your option) any later version.
+# 
+# pretty-printk is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with pretty-printk. If not, see <https://www.gnu.org/licenses/>.
+# 
+#
+
+# Pass debug=1 to enable debugging output (make debug=1)
+debug = 0
+
+ifeq ($(debug),1)
+ DEBUG_FLAGS = -O -g -DPP_DEBUG
+else
+ DEBUG_FLAGS = -O2
+endif

pretty_printk.h

@@ -31,14 +31,6 @@
 #define _pp(severity, format, args...) \
  printk(severity "%s: " #format "\n", THIS_MODULE->name, ##args)
 
-#define __FILENAME__ \
- (strrchr(__FILE__, '/') ? strrchr(__FILE__, '/') + 1 : __FILE__)
-
-#define _pp_debug(format, args...) \
- printk(KERN_DEBUG "%s (%s @ %s, %i): " #format "\n", \
- THIS_MODULE->name, __FUNCTION__, __FILENAME__, __LINE__, \
- ##args)
-
 #define pp_emerg(args...) _pp(KERN_EMERG, args)
 #define pp_alert(args...) _pp(KERN_ALERT, args)
 #define pp_crit(args...) _pp(KERN_CRIT, args)
@@ -47,6 +39,20 @@
 #define pp_note(args...) _pp(KERN_NOTICE, args)
 #define pp_info(args...) _pp(KERN_INFO, args)
 
+#undef _pp_debug
+#undef pp_debug
+
+#ifdef PP_DEBUG
+#define __FILENAME__ \
+ (strrchr(__FILE__, '/') ? strrchr(__FILE__, '/') + 1 : __FILE__)
+#define _pp_debug(format, args...) \
+ printk(KERN_DEBUG "%s (%s @ %s, %i): " #format "\n", \
+ THIS_MODULE->name, __FUNCTION__, __FILENAME__, __LINE__, \
+ ##args)
+
 #define pp_debug(args...) _pp_debug(args)
+#else
+#define pp_debug(...) // no debug output
+#endif
 
 #endif

pretty_printk_demo.c

@@ -44,15 +44,22 @@ static int __init pretty_printk_demo_init(void)
  pp_note("Notice severity");
  pp_info("Information severity");
 
+ // Appending multiple arguments
+ pp_emerg("Emergency, checking arguments, %s and %i", "AAA", 11);
+ pp_crit("Critical, checking arguments, %s and %i", "BBB", 22);
+ pp_err("Error, checking arguments, %s and %i", "CCC", 33);
+ pp_warn("Warning, checking arguments, %s and %i", "DDD", 44);
+ pp_note("Notice, checking arguments, %s and %i", "EEE", 55);
+ pp_info("Information, checking arguments, %s and %i", "FFF", 66);
+
  // Extended Metadata (function, filename and line number)
+ // pp_debug will only print when _PP_DEBUG is defined
  pp_debug("Debugging severity");
+ pp_debug("Debuggin, checking arguments, %s and %i", "char", 42);
 
- // Internal macro
- _pp(KERN_INFO, "Internal Macro...");
- _pp_debug("Internal Macro, Extended meta data for debugging");
-
- pp_info("Checking arguments, %s and %i", "char", 42);
- pp_debug("Checking arguments, %s and %i", "char", 42);
+ // Output for README.md
+ pp_warn("Shortcut for severity level and flushing '\n' character");
+ pp_debug("Extended metadata while printk-ing with debug=1 or PP_DEBUG");
 
  return 0;
 }