examples/embedlog: update example for embedlog-v0.7.0

Signed-off-by: Michał Łyszczek <michal.lyszczek@bofc.pl>

examples/embedlog/CMakeLists.txt

@@ -19,6 +19,11 @@
 # ##############################################################################
 
 if(CONFIG_EXAMPLES_EMBEDLOG)
+
+  if(CONFIG_EXAMPLES_EMBEDLOG_STRIP_ALL_STRINGS)
+    list(APPEND CFLAGS -DDISABLE_ALL_EMBEDLOG)
+  endif()
+
   nuttx_add_application(
     NAME
     ${CONFIG_EXAMPLES_EMBEDLOG_PROGNAME}

examples/embedlog/Kconfig

@@ -23,6 +23,39 @@ config EXAMPLES_EMBEDLOG
 
 if EXAMPLES_EMBEDLOG
 
+config EXAMPLES_EMBEDLOG_STRIP_ALL_STRINGS
+	bool "Disable embedlog (strip)"
+	default n
+	---help---
+		Enabled embedlog so you can disable it... sounds about right.
+
+		Enable this to replace all embedlog function calls with stub
+		functions that always return OK. This will effectively strip
+		final binary from all log strings making code considerably
+		smaller.
+
+		This may be useful in two cases (at least):
+
+		1) You develop your app on bigger version of target MCU, on
+		which you have a lot of memory. So on that version of the
+		build you can afford to enable good diagnostic logs. But
+		final image may be run on smaller version, on which logs
+		would not fit. In that case you can strip binary in final
+		production image. Thanks to that you will get logs in dev
+		env, but still maintain small footprint on production build.
+
+		2) You want to hide implementation details that could be
+		leaked with debug logs from final image.
+
+		It only makes sense to enable this on production type builds.
+		Linker will optimize out embedlog and remove all unused
+		functions, just as if embedlog was never built.
+
+		Enabling this will render embedlog example useless - it
+		will not print anything, but example will stil compile
+		and final image will be about 15kB smaller. But YMMV
+		depending how much strings you have in project.
+
 config EXAMPLES_EMBEDLOG_PROGNAME
 	string "Program name"
 	default "embedlog"

examples/embedlog/Makefile

@@ -27,6 +27,10 @@ PRIORITY = $(CONFIG_EXAMPLES_EMBEDLOG_PRIORITY)
 STACKSIZE = $(CONFIG_EXAMPLES_EMBEDLOG_STACKSIZE)
 MODULE = $(CONFIG_EXAMPLES_EMBEDLOG)
 
+ifeq ($(CONFIG_EXAMPLES_EMBEDLOG_STRIP_ALL_STRINGS),y)
+  CFLAGS += -DDISABLE_ALL_EMBEDLOG
+endif
+
 # embedlog Example
 
 MAINSRC = embedlog_main.c

examples/embedlog/embedlog_main.c

@@ -113,7 +113,6 @@ static void el_print_options(void)
   el_ooption(&g_el, EL_TS, EL_TS_LONG);
   el_ooption(&g_el, EL_TS, EL_TS_OFF);
   el_oprint(OELF, "no time information, if your heart desire it");
-  el_ooption(&g_el, EL_TS_FRACT, EL_TS_FRACT_NS);
 
   el_ooption(&g_el, EL_FINFO, 1);
   el_oprint(OELF, "log location is very useful for debugging");
@@ -121,6 +120,10 @@ static void el_print_options(void)
   el_ooption(&g_el, EL_TS, EL_TS_LONG);
   el_ooption(&g_el, EL_TS_TM, EL_TS_TM_REALTIME);
   el_ooption(&g_el, EL_PRINT_LEVEL, 1);
+
+  /* nuttx runs on rather slow cpus, so millisecond precision is enough */
+
+  el_ooption(&g_el, EL_TS_FRACT, EL_TS_FRACT_MS);
   el_oprint(OELF, "Different scenarios need different options");
   el_oprint(OELA, "So we can mix options however we want");
 
@@ -188,6 +191,10 @@ static void el_print_memory(void)
   el_oprint(OELI, "print the same region but this time with nice ascii "
                   "table");
   el_opmemory_table(OELI, s, sizeof(s));
+
+  el_ooption(&g_el, EL_PMEMORY_SPACE, 1);
+  el_oprint(OELI, "print whole ASCII table with additional spacing");
+  el_opmemory(OELI, ascii, sizeof(ascii));
 }
 
 /****************************************************************************
@@ -221,51 +228,18 @@ static void el_print_file(const char *workdir)
 
   snprintf(log_path, sizeof(log_path), "%s/log-rotate", workdir);
 
-  /* Enable file rotation, maximum 5 files will be created, none of the log
-   * files size shall exceed 512 bytes. Rotate size is low to present how
-   * rotation works, in real life this should be much higher, unless you
-   * really know what you are doing and understand the consequences of low
-   * rotate size.
-   */
-
-  el_ooption(&g_el, EL_FROTATE_NUMBER, 5);
-  el_ooption(&g_el, EL_FROTATE_SIZE, 512);
-
-  /* Tell embedlog to sync all buffers and metadata regarding log file.
-   * There are cases, when data (a lot of data) goes into block device,
-   * but metadata of the file are not updated when power loss occurs. This
-   * leads to data loss - even though they landed physically on block device
-   * like sdcard. To prevent losing too much data, you can define how often
-   * you want embedlog to call sync() functions. It basically translates to
-   * "how much data am I ready to loose?". In this example, we sync() once
-   * every 4096 bytes are stored into file.
-   */
-
-  el_ooption(&g_el, EL_FILE_SYNC_EVERY, 4096);
-
-  /* Setting above value to too small value, will cause sync() to be called
-   * very often (depending on how much data you log) and that may criple
-   * performance greatly. And there are situations when you are willing to
-   * loose some info or debug data (up to configured sync every value), but
-   * when critical error shows up, you want data to be synced immediately to
-   * minimize chance of losing information about critical error. For that
-   * you can define which log level will be synced *every* time regardless
-   * of sync every value. Here we will instruct embedlog to log prints that
-   * have severity higher or equal to critical (so critial, alert and fatal)
-   */
-
   el_ooption(&g_el, EL_FILE_SYNC_LEVEL, EL_CRIT);
 
-  /* Print logs to both file and standard error */
+  /* Enable logging to file with file rotation based on file size.
-
+   * Maximum 5 files will be created, none of the log files size shall
-  el_ooption(&g_el, EL_OUT, EL_OUT_FILE | EL_OUT_STDERR);
+   * exceed 512 bytes. Rotate size is low to present how rotation works, in
-
+   * real life this should be much higher, unless you really know what you
-  /* Register path to log file in embedlog. This will cause logger to look
+   * are doing and understand the consequences of low rotate size.
-   * for next valid log file (when log rotate in enabled) and will try to
+   * This function will also automatically enable file output without
-   * open file for reading.
+   * disabling any - already enabled - outputs.
    */
 
-  if (el_ooption(&g_el, EL_FPATH, log_path) != 0)
+  if (el_oenable_file_log(&g_el, log_path, 5, 512))
     {
       if (errno == ENAMETOOLONG || errno == EINVAL)
         {
@@ -286,6 +260,29 @@ static void el_print_file(const char *workdir)
       return;
     }
 
+  /* Tell embedlog to sync all buffers and metadata regarding log file.
+   *
+   * There are cases, when data (a lot of data) goes into block device,
+   * but metadata of the file are not updated when power loss occurs. This
+   * leads to data loss - even though they landed physically on block device
+   * like sdcard. To prevent losing too much data, you can define how often
+   * you want embedlog to call sync() functions. It basically translates to
+   * "how much data am I ready to loose?". In this example, we sync() once
+   * every 4096 bytes are stored into file.
+   *
+   * Setting that value to too small value, will cause sync() to be called
+   * very often (depending on how much data you log) and that may criple
+   * performance greatly. And there are situations when you are willing to
+   * loose some info or debug data (up to configured sync every value), but
+   * when critical error shows up, you want data to be synced immediately to
+   * minimize chance of losing information about critical error. For that
+   * you can define which log level will be synced *every* time regardless
+   * of 'sync every' value. Here we will instruct embedlog to log prints that
+   * have severity higher or equal to critical (so critial, alert and fatal)
+   */
+
+  el_oset_file_sync(&g_el, 4096, EL_CRIT);
+
   /* Now we can print messages */
 
   el_oprint(OELI, "Now we enabled log rotation");
@@ -317,7 +314,21 @@ int main(int argc, FAR char *argv[])
   el_oinit(&g_el);
 
   el_oprint(OELI, "Right after init, embedlog will print to stderr with "
-      "just log level information - these are default settings.");
+            "just log level information - these are default settings.");
+
+  el_oprint(OELI, "You can enable most common and usefull options with just "
+            "a few special functions");
+
+  el_oset_timestamp(&g_el, EL_TS_LONG, EL_TS_TM_REALTIME, EL_TS_FRACT_US);
+  el_oprint_extra_info(&g_el, 1);
+
+  el_oprint(OELI, "timestamp and information about log place in code is "
+            "most usefull for developer");
+  el_oprint(OELI, "If these are not enough, you can always really fine");
+  el_oprint(OELI, "tune embedlog behaviour with options");
+
+  el_oset_timestamp(&g_el, EL_TS_OFF, EL_TS_TM_REALTIME, EL_TS_FRACT_OFF);
+  el_oprint_extra_info(&g_el, 0);
 
   el_print_options();
   el_print_memory();