Add logic to re-direct debug output to a sysloggin device

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@4381 42af7a65-404d-4744-a932-0658087f49c3

ChangeLog

@@ -2453,4 +2453,7 @@
 	* drivers/ramlog.c:  Add a character driver that can substitute
 	  for /dev/console and or be used for logging debug output when there
 	  is no serial port available (such as when a telnet console is used).
+	* lib/stdio/lib_syslogstream:  Add a stream object that will be used to
+	  re-direct all debug output to the RAM log if CONFIG_SYSLOG and
+	  CONFIG_RAMLOG_SYSLOG are defined.
 

Documentation/NuttxPortingGuide.html

@@ -3941,6 +3941,49 @@ build
   </li>
 </ul>
 
+<p>
+  System Logging:
+</p>
+<ul>
+  <li>
+    <code>CONFIG_SYSLOG</code>:  Enables general system logging support.
+  </li>
+  <p>
+    At present, the only system loggin device is a circular buffer in RAM.
+    If <code>CONFIG_SYSLOG</code> is selected, then these options are also available.
+  </p>
+  <li>
+    <code>CONFIG_RAMLOG</code>: Enables the RAM logging feature
+  </li>
+  <li>
+    <code>CONFIG_RAMLOG_CONSOLE</code>: Use the RAM logging device as a system console.
+    If this feature is enabled (along with <code>CONFIG_DEV_CONSOLE</code>), then all
+    console output will be re-directed to a circular buffer in RAM.  This
+    is useful, for example, if the only console is a Telnet console.  Then
+    in that case, console output from non-Telnet threads will go to the
+    circular buffer and can be viewed using the NSH 'dmesg' command.
+  </li>
+  <li>
+    <code>CONFIG_RAMLOG_SYSLOG</code>: Use the RAM logging device for the syslogging
+    interface.  If this feature is enabled (along with <code>CONFIG_SYSLOG</code>),
+    then all debug output (only) will be re-directed to the circular
+    buffer in RAM.  This RAM log can be view from NSH using the 'dmesg'
+    command.
+  </li>
+  <li>
+    <code>CONFIG_RAMLOG_NPOLLWAITERS</code>: The number of threads than can be waiting
+    for this driver on poll().  Default: 4
+  </li>
+  <p>
+    If <code>CONFIG_RAMLOG_CONSOLE</code> or <code>CONFIG_RAMLOG_SYSLOG</code> is selected, then the
+    following may also be provided:
+  </p>
+  </li>
+  <li>
+    <code>CONFIG_RAMLOG_CONSOLE_BUFSIZE</code>: Size of the console RAM log.  Default: 1024
+  </li>
+</ul>
+
 <p>
  Kernel build options:
 </p>

arch/arm/src/common/up_initialize.c

@@ -43,6 +43,8 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/fs.h>
+#include <nuttx/ramlog.h>
+
 #include <arch/board/board.h>
 
 #include "up_arch.h"
@@ -159,6 +161,12 @@ void up_initialize(void)
   ramlog_consoleinit();
 #endif
 
+  /* Initialize the system logging device */
+
+#ifdef CONFIG_RAMLOG_SYSLOG
+  ramlog_sysloginit();
+#endif
+
   /* Initialize the netwok */
 
   up_netinitialize();

arch/arm/src/common/up_internal.h

@@ -81,6 +81,12 @@
 #  endif
 #endig
 
+/* Determine which device to use as the system loggin device */
+
+#ifndef CONFIG_SYSLOG
+#  undef CONFIG_RAMLOG_SYSLOG
+#endif
+
 /* Check if an interrupt stack size is configured */
 
 #ifndef CONFIG_ARCH_INTERRUPTSTACK
@@ -297,14 +303,6 @@ extern void lowconsole_init(void);
 # define lowconsole_init()
 #endif
 
-/* Defined in drivers/ramlog.c */
-
-#ifdef CONFIG_RAMLOG_CONSOLE
-extern void ramlog_consoleinit(void);
-#else
-# define ramlog_consoleinit()
-#endif
-
 /* DMA **********************************************************************/
 
 #ifdef CONFIG_ARCH_DMA

arch/avr/src/at32uc3/at32uc3_config.h

@@ -168,6 +168,12 @@
 #  endif
 #endig
 
+/* Determine which device to use as the system loggin device */
+
+#ifndef CONFIG_SYSLOG
+#  undef CONFIG_RAMLOG_SYSLOG
+#endif
+
 /* If GPIO IRQ support is defined, then a set of GPIOs must all be included */
 
 #if CONFIG_AVR32_GPIOIRQSETA == 0 && CONFIG_AVR32_GPIOIRQSETB == 0

arch/avr/src/at90usb/at90usb_config.h

@@ -87,6 +87,12 @@
 #  endif
 #endig
 
+/* Determine which device to use as the system loggin device */
+
+#ifndef CONFIG_SYSLOG
+#  undef CONFIG_RAMLOG_SYSLOG
+#endif
+
 /************************************************************************************
  * Public Types
  ************************************************************************************/

arch/avr/src/atmega/atmega_config.h

@@ -92,6 +92,12 @@
 #  endif
 #endig
 
+/* Determine which device to use as the system loggin device */
+
+#ifndef CONFIG_SYSLOG
+#  undef CONFIG_RAMLOG_SYSLOG
+#endif
+
 /************************************************************************************
  * Public Types
  ************************************************************************************/

arch/avr/src/common/up_initialize.c

@@ -43,6 +43,8 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/fs.h>
+#include <nuttx/ramlog.h>
+
 #include <arch/board/board.h>
 
 #include "up_arch.h"
@@ -76,6 +78,12 @@
 #  endif
 #endig
 
+/* Determine which device to use as the system loggin device */
+
+#ifndef CONFIG_SYSLOG
+#  undef CONFIG_RAMLOG_SYSLOG
+#endif
+
 /****************************************************************************
  * Private Types
  ****************************************************************************/
@@ -183,6 +191,12 @@ void up_initialize(void)
   ramlog_consoleinit();
 #endif
 
+  /* Initialize the system logging device */
+
+#ifdef CONFIG_RAMLOG_SYSLOG
+  ramlog_sysloginit();
+#endif
+
   /* Initialize the netwok */
 
   up_netinitialize();

arch/avr/src/common/up_internal.h

@@ -172,14 +172,6 @@ extern void lowconsole_init(void);
 # define lowconsole_init()
 #endif
 
-/* Defined in drivers/ramlog.c */
-
-#ifdef CONFIG_RAMLOG_CONSOLE
-extern void ramlog_consoleinit(void);
-#else
-# define ramlog_consoleinit()
-#endif
-
 /* Defined in chip/xxx_timerisr.c */
 
 extern void up_timerinit(void);

arch/hc/src/common/up_initialize.c

@@ -43,6 +43,7 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/fs.h>
+#include <nuttx/ramlog.h>
 
 #include "up_arch.h"
 #include "up_internal.h"
@@ -158,6 +159,12 @@ void up_initialize(void)
   ramlog_consoleinit();
 #endif
 
+  /* Initialize the system logging device */
+
+#ifdef CONFIG_RAMLOG_SYSLOG
+  ramlog_sysloginit();
+#endif
+
   /* Initialize the netwok */
 
   up_netinitialize();

arch/hc/src/common/up_internal.h

@@ -81,6 +81,12 @@
 #  endif
 #endig
 
+/* Determine which device to use as the system loggin device */
+
+#ifndef CONFIG_SYSLOG
+#  undef CONFIG_RAMLOG_SYSLOG
+#endif
+
 /* Check if an interrupt stack size is configured */
 
 #ifndef CONFIG_ARCH_INTERRUPTSTACK
@@ -178,12 +184,6 @@ extern void lowconsole_init(void);
 # define lowconsole_init()
 #endif
 
-#ifdef CONFIG_RAMLOG_CONSOLE
-extern void ramlog_consoleinit(void);
-#else
-# define ramlog_consoleinit()
-#endif
-
 extern void up_lowputc(char ch);
 extern void up_puts(const char *str);
 extern void up_lowputs(const char *str);

arch/mips/src/common/up_initialize.c

@@ -43,6 +43,8 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/fs.h>
+#include <nuttx/ramlog.h>
+
 #include <arch/board/board.h>
 
 #include "up_arch.h"
@@ -159,6 +161,12 @@ void up_initialize(void)
   ramlog_consoleinit();
 #endif
 
+  /* Initialize the system logging device */
+
+#ifdef CONFIG_RAMLOG_SYSLOG
+  ramlog_sysloginit();
+#endif
+
   /* Initialize the netwok */
 
   up_netinitialize();

arch/mips/src/common/up_internal.h

@@ -81,6 +81,12 @@
 #  endif
 #endig
 
+/* Determine which device to use as the system loggin device */
+
+#ifndef CONFIG_SYSLOG
+#  undef CONFIG_RAMLOG_SYSLOG
+#endif
+
 /* Check if an interrupt stack size is configured */
 
 #ifndef CONFIG_ARCH_INTERRUPTSTACK
@@ -188,14 +194,6 @@ extern void lowconsole_init(void);
 # define lowconsole_init()
 #endif
 
-/* Defined in drivers/ramlog.c */
-
-#ifdef CONFIG_RAMLOG_CONSOLE
-extern void ramlog_consoleinit(void);
-#else
-# define ramlog_consoleinit()
-#endif
-
 /* Debug */
 
 #ifdef CONFIG_ARCH_STACKDUMP

arch/sh/src/common/up_initialize.c

@@ -43,6 +43,7 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/fs.h>
+#include <nuttx/ramlog.h>
 
 #include "up_arch.h"
 #include "up_internal.h"
@@ -150,6 +151,12 @@ void up_initialize(void)
   ramlog_consoleinit();
 #endif
 
+  /* Initialize the system logging device */
+
+#ifdef CONFIG_RAMLOG_SYSLOG
+  ramlog_sysloginit();
+#endif
+
   /* Initialize the netwok */
 
   up_netinitialize();

arch/sh/src/common/up_internal.h

@@ -85,6 +85,12 @@
 #  endif
 #endig
 
+/* Determine which device to use as the system loggin device */
+
+#ifndef CONFIG_SYSLOG
+#  undef CONFIG_RAMLOG_SYSLOG
+#endif
+
 /* Check if an interrupt stack size is configured */
 
 #ifndef CONFIG_ARCH_INTERRUPTSTACK
@@ -177,14 +183,6 @@ extern void lowconsole_init(void);
 # define lowconsole_init()
 #endif
 
-/* Defined in drivers/ramlog.c */
-
-#ifdef CONFIG_RAMLOG_CONSOLE
-extern void ramlog_consoleinit(void);
-#else
-# define ramlog_consoleinit()
-#endif
-
 /* Defined in up_watchdog.c */
 
 extern void up_wdtinit(void);

arch/sim/src/up_initialize.c

@@ -1,8 +1,8 @@
 /****************************************************************************
  * up_initialize.c
  *
- *   Copyright (C) 2007-2009, 2011 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2009, 2011-2012 Gregory Nutt. All rights reserved.
- *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -43,6 +43,7 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/fs.h>
+#include <nuttx/ramlog.h>
 
 #include "up_internal.h"
 
@@ -50,6 +51,12 @@
  * Private Definitions
  ****************************************************************************/
 
+/* Determine which device to use as the system loggin device */
+
+#ifndef CONFIG_SYSLOG
+#  undef CONFIG_RAMLOG_SYSLOG
+#endif
+
 /****************************************************************************
  * Private Data
  ****************************************************************************/
@@ -99,6 +106,10 @@ void up_initialize(void)
   devzero_register();       /* Standard /dev/zero */
   up_devconsole();          /* Our private /dev/console */
 
+#ifdef CONFIG_RAMLOG_SYSLOG
+  ramlog_sysloginit();      /* System logging device */
+#endif
+
 #if defined(CONFIG_FS_FAT) && !defined(CONFIG_DISABLE_MOUNTPOINT)
   up_registerblockdevice(); /* Our FAT ramdisk at /dev/ram0 */
 #endif

arch/x86/src/common/up_initialize.c

@@ -43,6 +43,8 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/fs.h>
+#include <nuttx/ramlog.h>
+
 #include <arch/board/board.h>
 
 #include "up_arch.h"
@@ -159,6 +161,12 @@ void up_initialize(void)
   ramlog_consoleinit();
 #endif
 
+  /* Initialize the system logging device */
+
+#ifdef CONFIG_RAMLOG_SYSLOG
+  ramlog_sysloginit();
+#endif
+
   /* Initialize the netwok */
 
   up_netinitialize();

arch/x86/src/common/up_internal.h

@@ -80,6 +80,12 @@
 #  endif
 #endig
 
+/* Determine which device to use as the system loggin device */
+
+#ifndef CONFIG_SYSLOG
+#  undef CONFIG_RAMLOG_SYSLOG
+#endif
+
 /* Check if an interrupt stack size is configured */
 
 #ifndef CONFIG_ARCH_INTERRUPTSTACK
@@ -203,14 +209,6 @@ extern void lowconsole_init(void);
 # define lowconsole_init()
 #endif
 
-/* Defined in drivers/ramlog.c */
-
-#ifdef CONFIG_RAMLOG_CONSOLE
-extern void ramlog_consoleinit(void);
-#else
-# define ramlog_consoleinit()
-#endif
-
 /* Defined in up_watchdog.c */
 
 extern void up_wdtinit(void);

arch/z16/src/common/up_initialize.c

@@ -44,6 +44,8 @@
 #include <nuttx/arch.h>
 #include <nuttx/fs.h>
 #include <nuttx/mm.h>
+#include <nuttx/ramlog.h>
+
 #include <arch/board/board.h>
 
 #include "up_internal.h"
@@ -174,6 +176,12 @@ void up_initialize(void)
   ramlog_consoleinit();
 #endif
 
+  /* Initialize the system logging device */
+
+#ifdef CONFIG_RAMLOG_SYSLOG
+  ramlog_sysloginit();
+#endif
+
   /* Initialize the netwok */
 
   up_netinitialize();

arch/z16/src/common/up_internal.h

@@ -71,6 +71,12 @@
 #  define USE_EARLYSERIALINIT 1
 #endif
 
+/* Determine which device to use as the system loggin device */
+
+#ifndef CONFIG_SYSLOG
+#  undef CONFIG_RAMLOG_SYSLOG
+#endif
+
 /* Macros for portability */
 
 #define IN_INTERRUPT             (current_regs != NULL)
@@ -140,12 +146,6 @@ extern void up_serialinit(void);
 extern void lowconsole_init(void);
 #endif
 
-/* Defined in drivers/ramlog.c */
-
-#ifdef CONFIG_RAMLOG_CONSOLE
-extern void ramlog_consoleinit(void);
-#endif
-
 /* Defined in up_timerisr.c */
 
 extern void up_timerinit(void);

configs/README.txt

@@ -357,6 +357,32 @@ defconfig -- This is a configuration file similar to the Linux
 		CONFIG_SIG_SIGWORK - The signal number that will be used to wake-up
 		  the worker thread.  Default: 4
 
+	System Logging:
+		CONFIG_SYSLOG enables general system logging support.
+
+		At present, the only system loggin device is a circular buffer in RAM.
+		If CONFIG_SYSLOG is selected, then these options are also available.
+
+		CONFIG_RAMLOG - Enables the RAM logging feature
+		CONFIG_RAMLOG_CONSOLE - Use the RAM logging device as a system console.
+		  If this feature is enabled (along with CONFIG_DEV_CONSOLE), then all
+		  console output will be re-directed to a circular buffer in RAM.  This
+		  is useful, for example, if the only console is a Telnet console.  Then
+		  in that case, console output from non-Telnet threads will go to the
+		  circular buffer and can be viewed using the NSH 'dmesg' command.
+		CONFIG_RAMLOG_SYSLOG - Use the RAM logging device for the syslogging
+		  interface.  If this feature is enabled (along with CONFIG_SYSLOG),
+		  then all debug output (only) will be re-directed to the circular
+		  buffer in RAM.  This RAM log can be view from NSH using the 'dmesg'
+		  command.
+		CONFIG_RAMLOG_NPOLLWAITERS - The number of threads than can be waiting
+		 for this driver on poll().  Default: 4
+
+		If CONFIG_RAMLOG_CONSOLE or CONFIG_RAMLOG_SYSLOG is selected, then the
+		following may also be provided:
+
+		CONFIG_RAMLOG_CONSOLE_BUFSIZE - Size of the console RAM log.  Default: 1024
+
 	Kernel build options:
 		CONFIG_NUTTX_KERNEL - Builds NuttX as a separately compiled kernel.
 		CONFIG_SYS_RESERVED - Reserved system call values for use

drivers/ramlog.c

@@ -93,6 +93,15 @@ struct ramlog_dev_s
 /****************************************************************************
  * Private Function Prototypes
  ****************************************************************************/
+/* Helper functions */
+
+#ifndef CONFIG_DISABLE_POLL
+static void ramlog_pollnotify(FAR struct ramlog_dev_s *priv,
+                              pollevent_t eventset);
+#endif
+static ssize_t ramlog_addchar(FAR struct ramlog_dev_s *priv, char ch);
+
+/* Character driver methods */
 
 static ssize_t ramlog_read(FAR struct file *, FAR char *, size_t);
 static ssize_t ramlog_write(FAR struct file *, FAR const char *, size_t);
@@ -118,10 +127,13 @@ static const struct file_operations g_ramlogfops =
 #endif
 };
 
-/* This is the pre-allocated buffer used for the console RAM log */
+/* This is the pre-allocated buffer used for the console RAM log and/or
+ * for the syslogging function.
+ */
 
-#ifdef CONFIG_RAMLOG_CONSOLE
+#if defined(CONFIG_RAMLOG_CONSOLE) || defined(CONFIG_RAMLOG_SYSLOG)
-static char g_consoleramlog[CONFIG_RAMLOG_CONSOLE_BUFSIZE];
+static struct ramlog_dev_s g_sysdev;
+static char                g_sysbuffer[CONFIG_RAMLOG_CONSOLE_BUFSIZE];
 #endif
 
 /****************************************************************************
@@ -133,7 +145,8 @@ static char g_consoleramlog[CONFIG_RAMLOG_CONSOLE_BUFSIZE];
  ****************************************************************************/
 
 #ifndef CONFIG_DISABLE_POLL
-static void ramlog_pollnotify(FAR struct ramlog_dev_s *priv, pollevent_t eventset)
+static void ramlog_pollnotify(FAR struct ramlog_dev_s *priv,
+            pollevent_t eventset)
 {
   FAR struct pollfd *fds;
   irqstate_t flags;
@@ -160,6 +173,46 @@ static void ramlog_pollnotify(FAR struct ramlog_dev_s *priv, pollevent_t eventse
 #  define ramlog_pollnotify(priv,event)
 #endif
 
+/****************************************************************************
+ * Name: ramlog_addchar
+ ****************************************************************************/
+
+static int ramlog_addchar(FAR struct ramlog_dev_s *priv, char ch)
+{
+  irqstate_t flags;
+  int nexthead;
+
+  /* Disable interrupts (in case we are NOT called from interrupt handler) */
+
+  flags = irqsave();
+
+  /* Calculate the write index AFTER the next byte is written */
+
+  nexthead = priv->rl_head + 1;
+  if (nexthead >= priv->rl_bufsize)
+    {
+      nexthead = 0;
+    }
+
+  /* Would the next write overflow the circular buffer? */
+
+  if (nexthead == priv->rl_tail)
+    {
+      /* Yes... then break out of the loop to return an indication that
+       * nothing was saved in the buffer.
+       */
+
+      return -EBUSY;
+    }
+
+  /* No... copy the byte and re-enable interrupts */
+
+  priv->rl_buffer[priv->rl_head] = ch;
+  priv->rl_head = nexthead;
+  irqrestore(flags);
+  return OK;
+}
+
 /****************************************************************************
  * Name: ramlog_read
  ****************************************************************************/
@@ -310,10 +363,12 @@ static ssize_t ramlog_read(FAR struct file *filep, FAR char *buffer, size_t len)
   /* Notify all poll/select waiters that they can write to the FIFO */
 
 errout_without_sem:
+#ifndef CONFIG_DISABLE_POLL
   if (nread > 0)
     {
       ramlog_pollnotify(priv, POLLOUT);
     }
+#endif
   return nread;
 }
 
@@ -327,7 +382,6 @@ static ssize_t ramlog_write(FAR struct file *filep, FAR const char *buffer, size
   struct ramlog_dev_s *priv;
   irqstate_t flags;
   ssize_t nwritten;
-  int nexthead;
   int i;
 
   /* Some sanity checking */
@@ -346,34 +400,16 @@ static ssize_t ramlog_write(FAR struct file *filep, FAR const char *buffer, size
 
   for (nwritten = 0; nwritten < len; nwritten++)
     {
-      /* Disable interrupts (in case we are NOT called from interrupt handler) */
+      int ret = ramlog_addchar(priv, buffer[nwritten]);
-
+      if (ret < 0)
-      flags = irqsave();
-
-      /* Calculate the write index AFTER the next byte is written */
-
-      nexthead = priv->rl_head + 1;
-      if (nexthead >= priv->rl_bufsize)
         {
-          nexthead = 0;
+          /* The buffer is full and nothing was saved. Break out of the
-        }
+           * loop to return the number of bytes written up to this point.
-
+           * The data to be written is dropped on the floor.
-      /* Would the next write overflow the circular buffer? */
-
-      if (nexthead == priv->rl_tail)
-        {
-          /* Yes... then break out of the loop to return the number of bytes
-           * written.  The data to be written is dropped on the floor.
            */
 
-          return nwritten;
+          break;
         }
-
-      /* No... copy the byte and re-enable interrupts */
-
-      priv->rl_buffer[priv->rl_head] = buffer[nwritten];
-      priv->rl_head = nexthead;
-      irqrestore(flags);
     }
 
   /* Was anything written? */
@@ -393,6 +429,7 @@ static ssize_t ramlog_write(FAR struct file *filep, FAR const char *buffer, size
       /* Notify all poll/select waiters that they can write to the FIFO */
 
       ramlog_pollnotify(priv, POLLIN);
+      irqrestore(flags);
     }
  
   /* Return the number of bytes written */
@@ -526,6 +563,7 @@ errout:
  *
  ****************************************************************************/
 
+#if !defined(CONFIG_RAMLOG_CONSOLE) && !defined(CONFIG_RAMLOG_SYSLOG)
 int ramlog_register(FAR const char *devpath, FAR char *buffer, size_t buflen)
 {
   FAR struct ramlog_dev_s *priv;
@@ -558,6 +596,7 @@ int ramlog_register(FAR const char *devpath, FAR char *buffer, size_t buflen)
 
   return ret;
 }
+#endif
 
 /****************************************************************************
  * Name: ramlog_consoleinit
@@ -571,10 +610,57 @@ int ramlog_register(FAR const char *devpath, FAR char *buffer, size_t buflen)
 #ifdef CONFIG_RAMLOG_CONSOLE
 int ramlog_consoleinit(void)
 {
-  /* Register a RAM log as the console device */
+  FAR struct ramlog_dev_s *priv = &g_sysdev;
+  int ret;
 
-  return ramlog_register("/dev/console", g_consoleramlog,
+  /* Initialize the RAM loggin device structure */
-                         CONFIG_RAMLOG_CONSOLE_BUFSIZE);
+
+  sem_init(&priv->rl_exclsem, 0, 1);
+  sem_init(&priv->rl_waitsem, 0, 0);
+  priv->rl_bufsize = g_sysbuffer;
+  priv->rl_buffer  = CONFIG_RAMLOG_CONSOLE_BUFSIZE;
+
+  /* Register the console character driver */
+
+  ret = register_driver("/dev/console", &g_ramlogfops, 0666, priv);
+
+  /* Register the syslog character driver */
+
+#ifdef CONFIG_RAMLOG_SYSLOG
+  if (ret >= 0)
+    {
+      ret = register_driver("/dev/syslog", &g_ramlogfops, 0666, priv);
+    }
+#endif
+  return ret;
+}
+#endif
+
+/****************************************************************************
+ * Name: ramlog_sysloginit
+ *
+ * Description:
+ *   Create the RAM logging device and register it at the specified path.
+ *   Mostly likely this path will be /dev/syslog
+ *
+ *   If CONFIG_RAMLOG_CONSOLE is also defined, then this functionality is
+ *   performed when ramlog_consoleinit() is called.
+ *
+ ****************************************************************************/
+
+#if !defined(CONFIG_RAMLOG_CONSOLE) && defined(CONFIG_RAMLOG_SYSLOG)
+int ramlog_sysloginit(void)
+{
+  FAR struct ramlog_dev_s *priv = &g_sysdev;
+
+  /* Initialize the RAM loggin device structure */
+
+  sem_init(&priv->rl_exclsem, 0, 1);
+  sem_init(&priv->rl_waitsem, 0, 0);
+  priv->rl_bufsize = g_sysbuffer;
+  priv->rl_buffer  = CONFIG_RAMLOG_CONSOLE_BUFSIZE;
+
+  return register_driver("/dev/syslog", &g_ramlogfops, 0666, priv);
 }
 #endif
 
@@ -591,8 +677,13 @@ int ramlog_consoleinit(void)
  *
  ****************************************************************************/
 
-#ifdef CONFIG_RAMLOG_SYSLOG
+#if defined(CONFIG_RAMLOG_CONSOLE) || defined(CONFIG_RAMLOG_SYSLOG)
-#  warning "Missing logic"
+int ramlog_putc(int ch)
+{
+  FAR struct ramlog_dev_s *priv = &g_sysdev;
+  (void)ramlog_addchar(priv, ch)
+  return ch;
+}
 #endif
 
 #endif /* CONFIG_RAMLOG */

include/nuttx/lib.h

@@ -2,8 +2,8 @@
  * include/nuttx/lib.h
  * Non-standard, internal APIs available in lib/.
  *
- *   Copyright (C) 2007-2009 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2009, 2012 Gregory Nutt. All rights reserved.
- *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -34,8 +34,8 @@
  *
  ****************************************************************************/
 
-#ifndef __LIB_H
+#ifndef __INCLUDE_NUTTX_LIB_H
-#define __LIB_H
+#define __INCLUDE_NUTTX_LIB_H
 
 /****************************************************************************
  * Included Files
@@ -80,4 +80,4 @@ EXTERN void                   lib_releaselist(FAR struct streamlist *list);
 #endif
 
 #endif /* __ASSEMBLY__ */
-#endif /* __LIB_H */
+#endif /* __INCLUDE_NUTTX_LIB_H */

include/nuttx/ramlog.h

@@ -63,18 +63,33 @@
 /* Configuration ************************************************************/
 /* CONFIG_RAMLOG - Enables the RAM logging feature
  * CONFIG_RAMLOG_CONSOLE - Use the RAM logging device as a system console.
+ *   If this feature is enabled (along with CONFIG_DEV_CONSOLE), then all
+ *   console output will be re-directed to a circular buffer in RAM.  This
+ *   is useful, for example, if the only console is a Telnet console.  Then
+ *   in that case, console output from non-Telnet threads will go to the
+ *   circular buffer and can be viewed using the NSH 'dmesg' command.
  * CONFIG_RAMLOG_SYSLOG - Use the RAM logging device for the syslogging
- *   interface.  This should have:
+ *   interface.  If this feature is enabled (along with CONFIG_SYSLOG),
- *   CONFIG_SYSLOG=ramlog
+ *   then all debug output (only) will be re-directed to the circular
+ *   buffer in RAM.  This RAM log can be view from NSH using the 'dmesg'
+ *   command.
  * CONFIG_RAMLOG_NPOLLWAITERS - The number of threads than can be waiting
  *   for this driver on poll().  Default: 4
  *
- * If CONFIG_RAMLOG_CONSOLE is selected, then the following may also be
+ * If CONFIG_RAMLOG_CONSOLE or CONFIG_RAMLOG_SYSLOG is selected, then the
- * provided:
+ * following may also be provided:
  *
  * CONFIG_RAMLOG_CONSOLE_BUFSIZE - Size of the console RAM log.  Default: 1024
  */
 
+#ifndef CONFIG_DEV_CONSOLE
+#  undef CONFIG_RAMLOG_CONSOLE
+#endif
+
+#ifndef CONFIG_SYSLOG
+#  undef CONFIG_RAMLOG_SYSLOG
+#endif
+
 #ifndef CONFIG_RAMLOG_NPOLLWAITERS
 #  define CONFIG_RAMLOG_NPOLLWAITERS 4
 #endif
@@ -104,19 +119,31 @@ extern "C" {
  *
  * Description:
  *   Create the RAM logging device and register it at the specified path.
- *   Mostly likely this path will be /dev/console
+ *   Mostly likely this path will be /dev/console.
+ *
+ *   This interface is not normally used but can be made available is
+ *   someone just wants to tinker with the RAM log as a generic character
+ *   device.  Normally both CONFIG_RAMLOG_CONSOLE and CONFIG_RAMLOG_SYSLOG
+ *   would be set (to capture all output in the log) -OR- just
+ *   CONFIG_RAMLOG_SYSLOG would be set to capture debug output only
+ *   in the log.
  *
  ****************************************************************************/
 
+#if !defined(CONFIG_RAMLOG_CONSOLE) && !defined(CONFIG_RAMLOG_SYSLOG)
 EXTERN int ramlog_register(FAR const char *devpath, FAR char *buffer,
                            size_t buflen);
+#endif
 
 /****************************************************************************
  * Name: ramlog_consoleinit
  *
  * Description:
  *   Create the RAM logging device and register it at the specified path.
- *   Mostly likely this path will be /dev/console
+ *   Mostly likely this path will be /dev/console.
+ *
+ *   If CONFIG_RAMLOG_SYSLOG is also defined, then the same RAM logging
+ *   device is also registered at /dev/syslog
  *
  ****************************************************************************/
 
@@ -124,6 +151,22 @@ EXTERN int ramlog_register(FAR const char *devpath, FAR char *buffer,
 EXTERN int ramlog_consoleinit(void)
 #endif
 
+/****************************************************************************
+ * Name: ramlog_sysloginit
+ *
+ * Description:
+ *   Create the RAM logging device and register it at the specified path.
+ *   Mostly likely this path will be /dev/syslog
+ *
+ *   If CONFIG_RAMLOG_CONSOLE is also defined, then this functionality is
+ *   performed when ramlog_consoleinit() is called.
+ *
+ ****************************************************************************/
+
+#if !defined(CONFIG_RAMLOG_CONSOLE) && defined(CONFIG_RAMLOG_SYSLOG)
+EXTERN int ramlog_sysloginit(void)
+#endif
+
 /****************************************************************************
  * Name: ramlog
  *
@@ -137,8 +180,8 @@ EXTERN int ramlog_consoleinit(void)
  *
  ****************************************************************************/
 
-#ifdef CONFIG_RAMLOG_SYSLOG
+#if defined(CONFIG_RAMLOG_CONSOLE) || defined(CONFIG_RAMLOG_SYSLOG)
-#  warning "Missing logic"
+EXTERN int ramlog_putc(int ch);
 #endif
 
 #undef EXTERN

include/nuttx/streams.h

@@ -1,8 +1,8 @@
 /****************************************************************************
  * include/nuttx/streams.h
  *
- *   Copyright (C) 2009, 2011 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2009, 2011-2012 Gregory Nutt. All rights reserved.
- *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -268,6 +268,25 @@ EXTERN void lib_zeroinstream(FAR struct lib_instream_s *zeroinstream);
 EXTERN void lib_nullinstream(FAR struct lib_instream_s *nullinstream);
 EXTERN void lib_nulloutstream(FAR struct lib_outstream_s *nulloutstream);
 
+/****************************************************************************
+ * Name: lib_sylogstream
+ *
+ * Description:
+ *   Initializes a stream for use with the configured syslog interface.
+ *
+ * Input parameters:
+ *   lowoutstream - User allocated, uninitialized instance of struct
+ *                  lib_lowoutstream_s to be initialized.
+ *
+ * Returned Value:
+ *   None (User allocated instance initialized).
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_SYSLOG
+EXTERN void lib_sylogstream(FAR struct lib_outstream_s *stream);
+#endif
+
 #undef EXTERN
 #if defined(__cplusplus)
 }

lib/stdio/Make.defs

@@ -52,6 +52,10 @@ STDIO_SRCS += lib_fopen.c lib_fclose.c lib_fread.c lib_libfread.c lib_fseek.c \
 endif
 endif
 
+ifdef ($(CONFIG_SYSLOG)
+STDIO_SRCS += lib_syslogstream.c
+endif
+
 ifeq ($(CONFIG_LIBC_FLOATINGPOINT),y)
 STDIO_SRCS += lib_dtoa.c
 endif

lib/stdio/lib_lowprintf.c

@@ -1,8 +1,8 @@
 /****************************************************************************
  * lib/stdio/lib_lowprintf.c
  *
- *   Copyright (C) 2007-2009, 2011 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2009, 2011-2012 Gregory Nutt. All rights reserved.
- *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -82,17 +82,19 @@
  * Name: lib_lowvprintf
  ****************************************************************************/
 
-#ifdef CONFIG_ARCH_LOWPUTC
+#if defined(CONFIG_ARCH_LOWPUTC) || defined(CONFIG_SYSLOG)
 
 int lib_lowvprintf(const char *fmt, va_list ap)
 {
   struct lib_outstream_s stream;
 
-  /* Wrap the stdout in a stream object and let lib_vsprintf
+  /* Wrap the stdout in a stream object and let lib_vsprintf do the work. */
-   * do the work.
-   */
 
+#if defined(CONFIG_RAMLOG_CONSOLE) || defined(CONFIG_RAMLOG_SYSLOG)
+  lib_syslogstream((FAR struct lib_outstream_s *)&stream);
+#else
   lib_lowoutstream((FAR struct lib_outstream_s *)&stream);
+#endif
   return lib_vsprintf((FAR struct lib_outstream_s *)&stream, fmt, ap);
 }
 
@@ -111,4 +113,4 @@ int lib_lowprintf(const char *fmt, ...)
   return ret;
 }
 
-#endif /* CONFIG_ARCH_LOWPUTC */
+#endif /* CONFIG_ARCH_LOWPUTC || CONFIG_SYSLOG*/

lib/stdio/lib_rawprintf.c

@@ -1,8 +1,8 @@
 /****************************************************************************
  * lib/stdio/lib_rawprintf.c
  *
- *   Copyright (C) 2007-2009, 2011 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2009, 2011-2012 Gregory Nutt. All rights reserved.
- *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -83,7 +83,18 @@
 
 int lib_rawvprintf(const char *fmt, va_list ap)
 {
-#if CONFIG_NFILE_DESCRIPTORS > 0
+#if defined(CONFIG_SYSLOG)
+
+  struct lib_outstream_s stream;
+
+  /* Wrap the low-level output in a stream object and let lib_vsprintf
+   * do the work.
+   */
+
+  lib_syslogstream((FAR struct lib_outstream_s *)&stream);
+  return lib_vsprintf((FAR struct lib_outstream_s *)&stream, fmt, ap);
+
+#elif CONFIG_NFILE_DESCRIPTORS > 0
 
   struct lib_rawoutstream_s rawoutstream;
 

lib/stdio/lib_syslogstream.c

@@ -0,0 +1,103 @@
+/****************************************************************************
+ * lib/stdio/lib_syslogstream.c
+ *
+ *   Copyright (C) 2023 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <unistd.h>
+#include <errno.h>
+
+#include <nuttx/ramlog.h>
+
+#include "lib_internal.h"
+
+#ifdef CONFIG_SYSLOG
+
+/****************************************************************************
+ * Pre-processor definition
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: syslogstream_putc
+ ****************************************************************************/
+
+static void syslogstream_putc(FAR struct lib_outstream_s *this, int ch)
+{
+  /* At present, the RAM log is the only supported logging device */
+
+#ifdef CONFIG_RAMLOG_SYSLOG
+  (void)ramlog_putc(ch);
+  this->nput++;
+#endif
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: lib_sylogstream
+ *
+ * Description:
+ *   Initializes a stream for use with the coinfigured syslog interface.
+ *
+ * Input parameters:
+ *   lowoutstream - User allocated, uninitialized instance of struct
+ *                  lib_lowoutstream_s to be initialized.
+ *
+ * Returned Value:
+ *   None (User allocated instance initialized).
+ *
+ ****************************************************************************/
+
+void lib_sylogstream(FAR struct lib_outstream_s *stream)
+{
+  stream->put   = syslogstream_putc;
+#ifdef CONFIG_STDIO_LINEBUFFER
+  stream->flush = lib_noflush;
+#endif
+  stream->nput  = 0;
+}
+
+#endif /* CONFIG_SYSLOG */
+
+

tools/mkconfig.c

@@ -1,8 +1,8 @@
 /****************************************************************************
  * tools/mkconfig.c
  *
- *   Copyright (C) 2007-2011 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2012 Gregory Nutt. All rights reserved.
- *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -144,7 +144,13 @@ int main(int argc, char **argv, char **envp)
   printf("# if CONFIG_NFILE_STREAMS > 0 && CONFIG_NFILE_STREAMS < 3\n");
   printf("#  undef CONFIG_NFILE_STREAMS\n");
   printf("#  define CONFIG_NFILE_STREAMS 3\n");
-  printf("# endif\n");
+  printf("# endif\n\n");
+  printf("/* If no console is selected, then disable all console devices */\n\n");
+  printf("#else\n");
+  printf("#  undef CONFIG_DEV_LOWCONSOLE\n");
+  printf("#  undef CONFIG_RAMLOG_CONSOLE\n");
+  printf("#  undef CONFIG_CDCACM_CONSOLE\n");
+  printf("#  undef CONFIG_PL2303_CONSOLE\n");
   printf("#endif\n\n");
   printf("/* If priority inheritance is disabled, then do not allocate any\n");
   printf(" * associated resources.\n");