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drivers/serial/serial.c open, read, write, and poll methods will not return a short transfer or an EINTR error if a signal is received while waiting (only)

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git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5022 42af7a65-404d-4744-a932-0658087f49c3
This commit is contained in:
patacongo 2012-08-12 17:37:04 +00:00
parent 69b3ac08ea
commit b7a1b00c08
17 changed files with 338 additions and 115 deletions
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4
ChangeLog
View File

@ -3154,3 +3154,7 @@
* arch/arm/src/stm32/stm32f2xx_dma.c and stm32f4xx_dma.c: Backed out the
DMA priority change just above. The reduced SD card frequency was
necessary and sufficient to resolve the problem.
* drivers/serial/serial.c: open, read, write, and poll methods may now
abort return EINTR (or a short transfer size) if a signal is received
while waiting to receive or send serial data. This behavior is required
by POSIX.

19
TODO
View File

@ -1,4 +1,4 @@
NuttX TODO List (Last updated August 7, 2012)
NuttX TODO List (Last updated August 12, 2012)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
This file summarizes known NuttX bugs, limitations, inconsistencies with
@ -16,7 +16,7 @@ nuttx/
(17) Network (net/, drivers/net)
(3) USB (drivers/usbdev, drivers/usbhost)
(11) Libraries (lib/)
(10) File system/Generic drivers (fs/, drivers/)
(9) File system/Generic drivers (fs/, drivers/)
(5) Graphics subystem (graphics/)
(1) Pascal add-on (pcode/)
(1) Documentation (Documentation/)
@ -750,21 +750,6 @@ o File system / Generic drivers (fs/, drivers/)
Status: Open
Priority: Low
Title: SERIAL DRIVER DOES NOT RETURN WHEN SIGNAL RECEIVED
Description: The serial driver (drivers/serial) should return with an
error and errno=EINTR when an interrupt is received. However,
the serial driver just continues waiting:
static void uart_takesem(FAR sem_t *sem)
{
while (sem_wait(sem) != 0)
{
ASSERT(*get_errno_ptr() == EINTR);
}
}
Status: Open
Priority Medium
Title: POLLHUP SUPPORT
Description: All drivers that support the poll method should also report
POLLHUP event when the driver is closedd.

221
drivers/serial/serial.c
View File

@ -112,16 +112,29 @@ static const struct file_operations g_serialops =
* Name: uart_takesem
************************************************************************************/
static void uart_takesem(FAR sem_t *sem)
static int uart_takesem(FAR sem_t *sem, bool errout)
{
while (sem_wait(sem) != 0)
/* Loop, ignoring interrupts, until we have successfully acquired the semaphore */
while (sem_wait(sem) != OK)
{
/* The only case that an error should occur here is if
* the wait was awakened by a signal.
/* The only case that an error should occur here is if the wait was awakened
* by a signal.
*/
ASSERT(get_errno() == EINTR);
/* When the signal is received, should we errout? Or should we just continue
* waiting until we have the semaphore?
*/
if (errout)
{
return -EINTR;
}
}
return OK;
}
/************************************************************************************
@ -161,10 +174,11 @@ static void uart_pollnotify(FAR uart_dev_t *dev, pollevent_t eventset)
* Name: uart_putxmitchar
************************************************************************************/
static void uart_putxmitchar(FAR uart_dev_t *dev, int ch)
static int uart_putxmitchar(FAR uart_dev_t *dev, int ch)
{
irqstate_t flags;
int nexthead;
int ret;
/* Increment to see what the next head pointer will be. We need to use the "next"
* head pointer to determine when the circular buffer would overrun
@ -184,29 +198,43 @@ static void uart_putxmitchar(FAR uart_dev_t *dev, int ch)
{
dev->xmit.buffer[dev->xmit.head] = ch;
dev->xmit.head = nexthead;
return;
return OK;
}
else
{
/* Inform the interrupt level logic that we are waiting.
* This and the following steps must be atomic.
/* Inform the interrupt level logic that we are waiting. This and
* the following steps must be atomic.
*/
flags = irqsave();
dev->xmitwaiting = true;
/* Wait for some characters to be sent from the buffer
* with the TX interrupt enabled. When the TX interrupt
* is enabled, uart_xmitchars should execute and remove
* some of the data from the TX buffer.
/* Wait for some characters to be sent from the buffer with the TX
* interrupt enabled. When the TX interrupt is enabled, uart_xmitchars
* should execute and remove some of the data from the TX buffer.
*/
uart_enabletxint(dev);
uart_takesem(&dev->xmitsem);
ret = uart_takesem(&dev->xmitsem, true);
uart_disabletxint(dev);
irqrestore(flags);
/* Check if we were awakened by signal. */
if (ret < 0)
{
/* A signal received while waiting for the xmit buffer to become
* non-full will abort the transfer.
*/
return -EINTR;
}
}
}
/* We won't get here */
return OK;
}
/************************************************************************************
@ -241,9 +269,10 @@ static ssize_t uart_irqwrite(FAR uart_dev_t *dev, FAR const char *buffer, size_t
static ssize_t uart_write(FAR struct file *filep, FAR const char *buffer, size_t buflen)
{
FAR struct inode *inode = filep->f_inode;
FAR uart_dev_t *dev = inode->i_private;
ssize_t ret = buflen;
FAR struct inode *inode = filep->f_inode;
FAR uart_dev_t *dev = inode->i_private;
ssize_t nread = buflen;
int ret;
/* We may receive console writes through this path from
* interrupt handlers and from debug output in the IDLE task!
@ -266,9 +295,18 @@ static ssize_t uart_write(FAR struct file *filep, FAR const char *buffer, size_t
}
}
/* Only one user can be accessing dev->xmit.head at once */
/* Only one user can access dev->xmit.head at a time */
uart_takesem(&dev->xmit.sem);
ret = (ssize_t)uart_takesem(&dev->xmit.sem, true);
if (ret < 0)
{
/* A signal received while waiting for access to the xmit.head will
* abort the transfer. After the transfer has started, we are committed
* and signals will be ignored.
*/
return ret;
}
/* Loop while we still have data to copy to the transmit buffer.
* we add data to the head of the buffer; uart_xmitchars takes the
@ -280,15 +318,50 @@ static ssize_t uart_write(FAR struct file *filep, FAR const char *buffer, size_t
{
int ch = *buffer++;
/* Put the character into the transmit buffer */
uart_putxmitchar(dev, ch);
/* If this is the console, then we should replace LF with LF-CR */
/* If this is the console, then we should replace LF with CR-LF */
ret = OK;
if (dev->isconsole && ch == '\n')
{
uart_putxmitchar(dev, '\r');
ret = uart_putxmitchar(dev, '\r');
}
/* Put the character into the transmit buffer */
if (ret == OK)
{
ret = uart_putxmitchar(dev, ch);
}
/* Were we awakened by a signal? That should be the only condition that
* uart_putxmitchar() should return an error.
*/
if (ret < 0)
{
/* POSIX requires that we return -1 and errno set if no data was
* transferred. Otherwise, we return the number of bytes in the
* interrupted transfer.
*/
if (buflen < nread)
{
/* Some data was transferred. Return the number of bytes that were
* successfully transferred.
*/
nread -= buflen;
}
else
{
/* No data was transferred. Return -EINTR. The VFS layer will
* set the errno value appropriately).
*/
nread = -EINTR;
}
break;
}
}
@ -298,7 +371,7 @@ static ssize_t uart_write(FAR struct file *filep, FAR const char *buffer, size_t
}
uart_givesem(&dev->xmit.sem);
return ret;
return nread;
}
/************************************************************************************
@ -312,10 +385,20 @@ static ssize_t uart_read(FAR struct file *filep, FAR char *buffer, size_t buflen
irqstate_t flags;
ssize_t recvd = 0;
int16_t tail;
int ret;
/* Only one user can be accessing dev->recv.tail at once */
/* Only one user can access dev->recv.tail at a time */
uart_takesem(&dev->recv.sem);
ret = uart_takesem(&dev->recv.sem, true);
if (ret < 0)
{
/* A signal received while waiting for access to the recv.tail will avort
* the transfer. After the transfer has started, we are committed and
* signals will be ignored.
*/
return ret;
}
/* Loop while we still have data to copy to the receive buffer.
* we add data to the head of the buffer; uart_xmitchars takes the
@ -352,6 +435,7 @@ static ssize_t uart_read(FAR struct file *filep, FAR char *buffer, size_t buflen
{
tail = 0;
}
dev->recv.tail = tail;
}
@ -426,12 +510,34 @@ static ssize_t uart_read(FAR struct file *filep, FAR char *buffer, size_t buflen
uart_enablerxint(dev);
/* Now wait with the Rx interrupt re-enabled. NuttX will
* automatically re-enable global interrupts when this
* thread goes to sleep.
* automatically re-enable global interrupts when this thread
* goes to sleep.
*/
uart_takesem(&dev->recvsem);
ret = uart_takesem(&dev->recvsem, true);
irqrestore(flags);
/* Was a signal received while waiting for data to be received? */
if (ret < 0)
{
/* POSIX requires that we return after a signal is received.
* If some bytes were read, we need to return the number of bytes
* read; if no bytes were read, we need to return -1 with the
* errno set correctly.
*/
if (recvd == 0)
{
/* No bytes were read, return -EINTR (the VFS layer will
* set the errno value appropriately.
*/
recvd = -EINTR;
}
break;
}
}
else
{
@ -472,7 +578,7 @@ int uart_poll(FAR struct file *filep, FAR struct pollfd *fds, bool setup)
FAR uart_dev_t *dev = inode->i_private;
pollevent_t eventset;
int ndx;
int ret = OK;
int ret;
int i;
/* Some sanity checking */
@ -486,7 +592,16 @@ int uart_poll(FAR struct file *filep, FAR struct pollfd *fds, bool setup)
/* Are we setting up the poll? Or tearing it down? */
uart_takesem(&dev->pollsem);
ret = uart_takesem(&dev->pollsem, true);
if (ret < 0)
{
/* A signal received while waiting for access to the poll data
* will abort the operation.
*/
return ret;
}
if (setup)
{
/* This is a request to set up the poll. Find an available
@ -514,31 +629,43 @@ int uart_poll(FAR struct file *filep, FAR struct pollfd *fds, bool setup)
goto errout;
}
/* Should immediately notify on any of the requested events?
/* Should we immediately notify on any of the requested events?
* First, check if the xmit buffer is full.
*
* Get exclusive access to the xmit buffer indices. NOTE: that we do not
* let this wait be interrupted by a signal (we probably should, but that
* would be a little awkward).
*/
eventset = 0;
(void)uart_takesem(&dev->xmit.sem, false);
uart_takesem(&dev->xmit.sem);
ndx = dev->xmit.head + 1;
if (ndx >= dev->xmit.size)
{
ndx = 0;
}
if (ndx != dev->xmit.tail)
{
eventset |= POLLOUT;
}
uart_givesem(&dev->xmit.sem);
/* Check if the receive buffer is empty */
/* Check if the receive buffer is empty
*
* Get exclusive access to the recv buffer indices. NOTE: that we do not
* let this wait be interrupted by a signal (we probably should, but that
* would be a little awkward).
*/
uart_takesem(&dev->recv.sem);
(void)uart_takesem(&dev->recv.sem, false);
if (dev->recv.head != dev->recv.tail)
{
eventset |= POLLIN;
}
uart_givesem(&dev->recv.sem);
if (eventset)
@ -588,7 +715,13 @@ static int uart_close(FAR struct file *filep)
FAR uart_dev_t *dev = inode->i_private;
irqstate_t flags;
uart_takesem(&dev->closesem);
/* Get exclusive access to the close semaphore (to synchronize open/close operations.
* NOTE: that we do not let this wait be interrupted by a signal. Technically, we
* should, but almost no one every checks the return value from close() so we avoid
* a potential memory leak by ignoring signals in this case.
*/
(void)uart_takesem(&dev->closesem, false);
if (dev->open_count > 1)
{
dev->open_count--;
@ -653,11 +786,19 @@ static int uart_open(FAR struct file *filep)
struct inode *inode = filep->f_inode;
uart_dev_t *dev = inode->i_private;
uint8_t tmp;
int ret = OK;
int ret;
/* If the port is the middle of closing, wait until the close is finished */
/* If the port is the middle of closing, wait until the close is finished.
* If a signal is received while we are waiting, then return EINTR.
*/
uart_takesem(&dev->closesem);
ret = uart_takesem(&dev->closesem, true);
if (ret < 0)
{
/* A signal received while waiting for the last close operation. */
return ret;
}
/* Start up serial port */
/* Increment the count of references to the device. */

17
include/netinet/arp.h
View File

@ -58,14 +58,17 @@
#define SIOCDARP _ARPIOC(2) /* Delete an ARP mapping */
#define SIOCGARP _ARPIOC(3) /* Get an ARP mapping */
/* Values for the FLAGS field in struct arpreq */
/* Definitions for bits in field arp_flags of struct arpreq. If the
* ATF_NETMASK flag is set, then arp_netmask should be valid. This should
* be set to 0xffffffff, or 0 to remove an existing arp entry.
*/
#define ATF_COM 0x01 /* Lookup complete */
#define ATF_PERM 0x02 /* Permanent entry */
#define ATF_PUBL 0x04 /* Publish entry */
#define ATF_USETRAILERS 0x10 /* Trailers requested */
#define ATF_NETMASK 0x20 /* Use a netmask */
#define ATF_DONTPUB 0x40 /* Don't answer */
#define ATF_COM (1 << 0) /* Lookup complete */
#define ATF_PERM (1 << 1) /* Permanent entry */
#define ATF_PUBL (1 << 2) /* Publish entry */
#define ATF_USETRAILERS (1 << 3) /* Trailers requested (obsolete) */
#define ATF_NETMASK (1 << 4) /* Use a netmask */
#define ATF_DONTPUB (1 << 5) /* Don't answer */
/****************************************************************************
* Public Type Definitions

1
include/nuttx/net/ioctl.h
View File

@ -149,6 +149,7 @@
/****************************************************************************
* Type Definitions
****************************************************************************/
/* See include/net/if.h */
/****************************************************************************
* Public Function Prototypes

2
lib/stdio/lib_libfwrite.c
View File

@ -2,7 +2,7 @@
* lib/stdio/lib_libfwrite.c
*
* Copyright (C) 2007-2009, 2011 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

17
lib/stdio/lib_lowinstream.c
View File

@ -1,8 +1,8 @@
/****************************************************************************
* lib/stdio/lib_lowinstream.c
*
* Copyright (C) 2007-2009, 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
* Copyright (C) 2007-2009, 2011-2012 Gregory Nutt. All rights reserved.
* 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
@ -42,7 +42,9 @@
#ifdef CONFIG_ARCH_LOWGETC
#include <stdio.h>
#include <assert.h>
#include <errno.h>
#include <nuttx/arch.h>
#include "lib_internal.h"
@ -57,10 +59,19 @@
static int lowinstream_getc(FAR struct lib_instream_s *this)
{
if (this && up_getc(ch) != EOF)
int ret;
DEBUGASSERT(this);
/* Get the next character from the incoming stream */
ret = up_getc(ch)
if (ret != EOF)
{
this->nget++;
}
return ret;
}
/****************************************************************************

5
lib/stdio/lib_lowoutstream.c
View File

@ -42,6 +42,7 @@
#ifdef CONFIG_ARCH_LOWPUTC
#include <stdio.h>
#include <assert.h>
#include <errno.h>
#include <nuttx/arch.h>
@ -57,7 +58,9 @@
static void lowoutstream_putc(FAR struct lib_outstream_s *this, int ch)
{
if (this && up_putc(ch) != EOF)
DEBUGASSERT(this);
if (up_putc(ch) != EOF)
{
this->nput++;
}

13
lib/stdio/lib_meminstream.c
View File

@ -1,8 +1,8 @@
/****************************************************************************
* lib/stdio/lib_meminstream.c
*
* Copyright (C) 2007-2009, 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
* Copyright (C) 2007-2009, 2011-2012 Gregory Nutt. All rights reserved.
* 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
@ -37,6 +37,8 @@
* Included Files
****************************************************************************/
#include <assert.h>
#include "lib_internal.h"
/****************************************************************************
@ -52,7 +54,11 @@ static int meminstream_getc(FAR struct lib_instream_s *this)
FAR struct lib_meminstream_s *mthis = (FAR struct lib_meminstream_s *)this;
int ret;
if (this && this->nget < mthis->buflen)
DEBUGASSERT(this);
/* Get the next character (if any) from the buffer */
if (this->nget < mthis->buflen)
{
ret = mthis->buffer[this->nget];
this->nget++;
@ -61,6 +67,7 @@ static int meminstream_getc(FAR struct lib_instream_s *this)
{
ret = EOF;
}
return ret;
}

6
lib/stdio/lib_memoutstream.c
View File

@ -37,6 +37,8 @@
* Included Files
****************************************************************************/
#include <assert.h>
#include "lib_internal.h"
/****************************************************************************
@ -51,12 +53,14 @@ static void memoutstream_putc(FAR struct lib_outstream_s *this, int ch)
{
FAR struct lib_memoutstream_s *mthis = (FAR struct lib_memoutstream_s *)this;
DEBUGASSERT(this);
/* If this will not overrun the buffer, then write the character to the
* buffer. Not that buflen was pre-decremented when the stream was
* created so it is okay to write past the end of the buflen by one.
*/
if (this && this->nput < mthis->buflen)
if (this->nput < mthis->buflen)
{
mthis->buffer[this->nput] = ch;
this->nput++;

5
lib/stdio/lib_nullinstream.c
View File

@ -1,8 +1,8 @@
/****************************************************************************
* lib/stdio/lib_nullinstream.c
*
* Copyright (C) 2007-2009, 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
* Copyright (C) 2007-2009, 2011-2012 Gregory Nutt. All rights reserved.
* 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
@ -39,6 +39,7 @@
#include <stdio.h>
#include <errno.h>
#include "lib_internal.h"
/****************************************************************************

3
lib/stdio/lib_nulloutstream.c
View File

@ -38,7 +38,9 @@
****************************************************************************/
#include <stdio.h>
#include <assert.h>
#include <errno.h>
#include "lib_internal.h"
/****************************************************************************
@ -47,6 +49,7 @@
static void nulloutstream_putc(FAR struct lib_outstream_s *this, int ch)
{
DEBUGASSERT(this);
this->nput++;
}

34
lib/stdio/lib_rawinstream.c
View File

@ -1,8 +1,8 @@
/****************************************************************************
* lib/stdio/lib_rawinstream.c
*
* Copyright (C) 2007-2009, 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
* Copyright (C) 2007-2009, 2011-2012 Gregory Nutt. All rights reserved.
* 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
@ -38,7 +38,9 @@
****************************************************************************/
#include <unistd.h>
#include <assert.h>
#include <errno.h>
#include "lib_internal.h"
/****************************************************************************
@ -52,23 +54,27 @@
static int rawinstream_getc(FAR struct lib_instream_s *this)
{
FAR struct lib_rawinstream_s *rthis = (FAR struct lib_rawinstream_s *)this;
int nwritten;
char ch;
if (this && rthis->fd >= 0)
DEBUGASSERT(this && rthis->fd >= 0);
/* Attempt to read one character */
nwritten = read(rthis->fd, &ch, 1);
if (nwritten == 1)
{
int nwritten;
do
{
nwritten = read(rthis->fd, &ch, 1);
if (nwritten == 1)
{
this->nget++;
return ch;
}
}
while (nwritten < 0 && get_errno() == EINTR);
this->nget++;
return ch;
}
/* Return EOF on any failure to read from the incoming byte stream. The
* only expected error is EINTER meaning that the read was interrupted
* by a signal. A Zero return value would indicated an end-of-file
* confition.
*/
DEBUGASSERT(nwritten == 0 || get_errno() == EINTR);
return EOF;
}

29
lib/stdio/lib_rawoutstream.c
View File

@ -38,7 +38,9 @@
****************************************************************************/
#include <unistd.h>
#include <assert.h>
#include <errno.h>
#include "lib_internal.h"
/****************************************************************************
@ -52,19 +54,28 @@
static void rawoutstream_putc(FAR struct lib_outstream_s *this, int ch)
{
FAR struct lib_rawoutstream_s *rthis = (FAR struct lib_rawoutstream_s *)this;
int nwritten;
char buffer = ch;
if (this && rthis->fd >= 0)
DEBUGASSERT(this && rthis->fd >= 0);
/* Loop until the character is successfully transferred */
for (;;)
{
int nwritten;
do
nwritten = write(rthis->fd, &buffer, 1);
if (nwritten == 1)
{
nwritten = write(rthis->fd, &buffer, 1);
if (nwritten == 1)
{
this->nput++;
}
this->nput++;
return;
}
while (nwritten < 0 && get_errno() == EINTR);
/* The only expected error is EINTR, meaning that the write operation
* was awakened by a signal. Zero would not be a valid return value
* either.
*/
DEBUGASSERT(nwritten < 0 && get_errno() == EINTR);
}
}

25
lib/stdio/lib_stdinstream.c
View File

@ -1,8 +1,8 @@
/****************************************************************************
* lib/stdio/lib_stdinstream.c
*
* Copyright (C) 2007-2009, 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
* Copyright (C) 2007-2009, 2011-2012 Gregory Nutt. All rights reserved.
* 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
@ -37,6 +37,8 @@
* Included Files
****************************************************************************/
#include <assert.h>
#include "lib_internal.h"
/****************************************************************************
@ -50,16 +52,19 @@
static int stdinstream_getc(FAR struct lib_instream_s *this)
{
FAR struct lib_stdinstream_s *sthis = (FAR struct lib_stdinstream_s *)this;
if (this)
int ret;
DEBUGASSERT(this);
/* Get the next character from the incoming stream */
ret = getc(sthis->stream);
if (ret != EOF)
{
int ret = getc(sthis->stream);
if (ret != EOF)
{
this->nget++;
}
return ret;
this->nget++;
}
return EOF;
return ret;
}
/****************************************************************************

24
lib/stdio/lib_stdoutstream.c
View File

@ -1,8 +1,8 @@
/****************************************************************************
* lib/stdio/lib_stdoutstream.c
*
* Copyright (C) 2007-2009, 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
* Copyright (C) 2007-2009, 2011-2012 Gregory Nutt. All rights reserved.
* 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
@ -38,6 +38,8 @@
****************************************************************************/
#include <fcntl.h>
#include <assert.h>
#include <errno.h>
#include "lib_internal.h"
@ -52,12 +54,26 @@
static void stdoutstream_putc(FAR struct lib_outstream_s *this, int ch)
{
FAR struct lib_stdoutstream_s *sthis = (FAR struct lib_stdoutstream_s *)this;
if (this)
int result;
DEBUGASSERT(this && sthis->stream);
/* Loop until the character is successfully transferred */
for (;;)
{
if (putc(ch, sthis->stream) != EOF)
result = fputc(ch, sthis->stream);
if (result != EOF)
{
this->nput++;
return;
}
/* EINTR (meaning that fputc was interrupted by a signal) is the only
* expected error.
*/
DEBUGASSERT(get_errno() == EINTR);
}
}

28
lib/stdio/lib_syslogstream.c
View File

@ -40,6 +40,7 @@
#include <nuttx/config.h>
#include <unistd.h>
#include <assert.h>
#include <errno.h>
#include <nuttx/syslog.h>
@ -62,10 +63,31 @@
static void syslogstream_putc(FAR struct lib_outstream_s *this, int ch)
{
/* Write the character to the supported logging device */
int ret;
(void)syslog_putc(ch);
this->nput++;
/* Try writing until the write was successful or until an irrecoverable
* error occurs.
*/
for (;;)
{
/* Write the character to the supported logging device */
ret = syslog_putc(ch);
if (ret == OK)
{
this->nput++;
return;
}
/* On failure syslog_putc will return a negated errno value. The
* errno variable will not be set. The special value -EINTR means that
* syslog_putc() was awakened by a signal. This is not a real error and
* must be ignored in this context.
*/
DEBUGASSERT(ret == -EINTR);
}
}
/****************************************************************************