Misc SYSLOG and STM32 serial fixes

git-svn-id: http://svn.code.sf.net/p/nuttx/code/trunk@5576 42af7a65-404d-4744-a932-0658087f49c3

nuttx/ChangeLog

@@ -4057,4 +4057,13 @@
 	  Serial was driver was not being built if there is no console
 	  device.  Obviously, the serial driver may be needed even in
 	  this case.
-
+	* arch/arm/src/stm32/stm32_serial.c: If there is a serial console,
+	  it would be ttyS0 and the others would be ttyS1-5.  If there
+	  is not serial console, was labeling them ttyS1-6; now labels them
+	  ttyS0-5.
+	* fs/fs_syslog.c: Can't handle SYSLOG output to character device from
+	  the IDLE task (because it can't block). syslog_putc now returns EOF
+	  on failure and sets errno.  Fixed some errors in error handling.
+	* libc/stdio/lib_syslogstream.c:  Checking of return value from
+	  syslog_putc was bogus.  Switching to EOF for all errors solves
+	  this.

nuttx/arch/arm/src/stm32/stm32_serial.c

@@ -1998,7 +1998,8 @@ void up_serialinit(void)
 {
 #ifdef HAVE_UART
   char devname[16];
-  unsigned i, j;
+  unsigned i;
+  unsigned minor = 0;
 #ifdef CONFIG_PM
   int ret;
 #endif
@@ -2015,6 +2016,7 @@ void up_serialinit(void)
 #if CONSOLE_UART > 0
   (void)uart_register("/dev/console", &uart_devs[CONSOLE_UART - 1]->dev);
   (void)uart_register("/dev/ttyS0",   &uart_devs[CONSOLE_UART - 1]->dev);
+  minor = 1;
 
   /* If we need to re-initialise the console to enable DMA do that here. */
 
@@ -2028,19 +2030,19 @@ void up_serialinit(void)
 
   strcpy(devname, "/dev/ttySx");
 
-  for (i = 0, j = 1; i < STM32_NUSART; i++)
+  for (i = 0; i < STM32_NUSART; i++)
     {
 
-      /* don't create a device for the console - we did that above */
+      /* Don't create a device for the console - we did that above */
 
       if ((uart_devs[i] == 0) || (uart_devs[i]->dev.isconsole))
         {
           continue;
         }
 
-      /* register USARTs as devices in increasing order */
+      /* Register USARTs as devices in increasing order */
 
-      devname[9] = '0' + j++;
+      devname[9] = '0' + minor++;
       (void)uart_register(devname, &uart_devs[i]->dev);
     }
 #endif /* HAVE UART */

nuttx/configs/stm32f4discovery/README.txt

@@ -1254,40 +1254,10 @@ Where <subdir> is one of the following:
         CONFIG_CDCACM=y                : The CDC/ACM driver must be built
         CONFIG_CDCACM_CONSOLE=y        : Enable the CDC/ACM USB console.
 
-        However, that configuration does not work.  It fails early probably because
+        NOTE: When you first start the USB console, you have hit ENTER a few
-        of some dependency on /dev/console before the USB connection is established.
-
-        But there is a work around for this that works better (but has some side
-        effects).  The following configuration will also create a NSH USB console
-        but this version will will use /dev/console.  Instead, it will use the
-        normal /dev/ttyACM0 USB serial device for the console:
-
-        CONFIG_STM32_OTGFS=y           : STM32 OTG FS support
-        CONFIG_USART2_SERIAL_CONSOLE=n : Disable the USART2 console
-        CONFIG_USBDEV=y                : USB device support must be enabled
-        CONFIG_CDCACM=y                : The CDC/ACM driver must be built
-        CONFIG_CDCACM_CONSOLE=n        : Don't use the CDC/ACM USB console.
-        CONFIG_NSH_USBCONSOLE=y        : Instead use some other USB device for the console
-
-        The particular USB device that is used is:
-
-        CONFIG_NSH_USBCONDEV="/dev/ttyACM0"
-
-        NOTE 1: When you first start the USB console, you have hit ENTER a few
         times before NSH starts.  The logic does this to prevent sending USB data
         before there is anything on the host side listening for USB serial input.
 
-        Now the side effects:
-
-        NOTE 2. When any other device other than /dev/console is used for a user
-        interface, linefeeds (\n) will not be expanded to carriage return /
-        linefeeds (\r\n).  You will need to set your terminal program to account
-        for this.
-
-        NOTE 3: /dev/console still exists and still refers to the serial port. So
-        you can still use certain kinds of debug output (see include/debug.h, all
-        of the interfaces based on lib_lowprintf will work in this configuration).
-
     9. USB OTG FS Host Support.  The following changes will enable support for
        a USB host on the STM32F4Discovery, including support for a mass storage
        class driver:

nuttx/fs/fs_syslog.c

@@ -42,6 +42,7 @@
 #include <sys/types.h>
 
 #include <stdint.h>
+#include <stdio.h>
 #include <unistd.h>
 #include <fcntl.h>
 #include <semaphore.h>
@@ -282,7 +283,7 @@ int syslog_initialize(void)
   if (!INODE_IS_DRIVER(inode))
 #endif
     {
-      ret = ENXIO;
+      ret = -ENXIO;
       goto errout_with_inode;
     }
 
@@ -290,7 +291,7 @@ int syslog_initialize(void)
 
   if (!inode->u.i_ops || !inode->u.i_ops->write)
     {
-      return -EACCES;
+      ret = -EACCES;
       goto errout_with_inode;
     }
 
@@ -346,8 +347,8 @@ int syslog_initialize(void)
   return OK;
 
  errout_with_inode:
-  g_sysdev.sl_state = SYSLOG_FAILURE;
   inode_release(inode);
+  g_sysdev.sl_state = SYSLOG_FAILURE;
   return ret;
 }
 
@@ -366,6 +367,8 @@ int syslog_initialize(void)
 int syslog_putc(int ch)
 {
   ssize_t nbytes;
+  uint8_t uch;
+  int errcode;
   int ret;
 
   /* Ignore any output:
@@ -382,7 +385,10 @@ int syslog_putc(int ch)
    * (4) Any debug output generated from interrupt handlers.  A disadvantage
    *     of using the generic character device for the SYSLOG is that it
    *     cannot handle debug output generated from interrupt level handlers.
-   * (5) If an irrecoverable failure occurred during initialization.  In
+   * (5) Any debug output generated from the IDLE loop.  The character
+   *     driver interface is blocking and the IDLE thread is not permitted
+   *     to block.
+   * (6) If an irrecoverable failure occurred during initialization.  In
    *     this case, we won't ever bother to try again (ever).
    *
    * NOTE: That the third case is different.  It applies only to the thread
@@ -390,11 +396,12 @@ int syslog_putc(int ch)
    * that is why that case is handled in syslog_semtake().
    */
 
-  /* Case (4) */
+  /* Cases (4) and (5) */
 
-  if (up_interrupt_context())
+  if (up_interrupt_context() || getpid() == 0)
     {
-      return -ENOSYS;  /* Not supported */
+      errcode = ENOSYS;
+      goto errout_with_errcode;
     }
 
   /* We can save checks in the usual case:  That after the SYSLOG device
@@ -408,14 +415,16 @@ int syslog_putc(int ch)
       if (g_sysdev.sl_state == SYSLOG_UNINITIALIZED ||
           g_sysdev.sl_state == SYSLOG_INITIALIZING)
        {
-         return -EAGAIN;  /* Can't access the SYSLOG now... maybe next time? */
+         errcode = EAGAIN; /* Can't access the SYSLOG now... maybe next time? */
+         goto errout_with_errcode;
        }
 
-      /* Case (5) */
+      /* Case (6) */
 
       if (g_sysdev.sl_state == SYSLOG_FAILURE)
         {
-          return -ENXIO;  /* There is no SYSLOG device */
+          errcode = ENXIO;  /* There is no SYSLOG device */
+          goto errout_with_errcode;
         }
 
       /* syslog_initialize() is called as soon as enough of the operating
@@ -443,7 +452,8 @@ int syslog_putc(int ch)
           if (ret < 0)
             {
               sched_unlock();
-              return ret;
+              errcode = -ret;
+              goto errout_with_errcode;
             }
         }
 
@@ -471,7 +481,8 @@ int syslog_putc(int ch)
        * way, we are outta here.
        */
 
-      return ret;
+      errcode = -ret;
+      goto errout_with_errcode;
     }
 
   /* Pre-pend a newline with a carriage return. */
@@ -497,19 +508,27 @@ int syslog_putc(int ch)
     {
       /* Write the non-newline character (and don't flush) */
 
-      nbytes = syslog_write(&ch, 1);
+      uch = (uint8_t)ch;
+      nbytes = syslog_write(&uch, 1);
     }
 
   syslog_givesem();
 
-  /* Check if the write was successful */
+  /* Check if the write was successful.  If not, nbytes will be
+   * a negated errno value.
+   */
 
   if (nbytes < 0)
     {
-      return nbytes;
+      errcode = -ret;
+      goto errout_with_errcode;
     }
 
   return ch;
+
+errout_with_errcode:
+  set_errno(errcode);
+  return EOF;
 }
 
 #endif /* CONFIG_SYSLOG && CONFIG_SYSLOG_CHAR */

nuttx/libc/stdio/lib_syslogstream.c

@@ -63,6 +63,7 @@
 
 static void syslogstream_putc(FAR struct lib_outstream_s *this, int ch)
 {
+  int errcode;
   int ret;
 
   /* Try writing until the write was successful or until an irrecoverable
@@ -71,22 +72,23 @@ static void syslogstream_putc(FAR struct lib_outstream_s *this, int ch)
 
   do
     {
-      /* Write the character to the supported logging device */
+      /* Write the character to the supported logging device.  On failure,
+       * syslog_putc returns EOF with the errno value set;
+       */
 
       ret = syslog_putc(ch);
-      if (ret == OK)
+      if (ret != EOF)
         {
           this->nput++;
           return;
         }
 
-      /* On failure syslog_putc will return a negated errno value.  The
+      /* The special errno value -EINTR means that syslog_putc() was
-       * errno variable will not be set.  The special value -EINTR means that
+       * awakened by a signal.  This is not a real error and must be
-       * syslog_putc() was awakened by a signal.  This is not a real error and
+       * ignored in this context.
-       * must be ignored in this context.
        */
     }
-  while (ret == -EINTR);
+  while (errno == -EINTR);
 }
 
 /****************************************************************************