Add support for seekable memory streams

libc/lib_internal.h

@@ -159,6 +159,12 @@ void  stream_semgive(FAR struct streamlist *list);
 int lib_noflush(FAR struct lib_outstream_s *this);
 #endif
 
+/* Defined in lib_libsnoflush.c */
+
+#ifdef CONFIG_STDIO_LINEBUFFER
+int lib_snoflush(FAR struct lib_sostream_s *this);
+#endif
+
 /* Defined in lib_libsprintf.c */
 
 int lib_sprintf(FAR struct lib_outstream_s *obj,

libc/stdio/Make.defs

@@ -41,9 +41,10 @@ CSRCS += lib_fileno.c lib_printf.c lib_syslog.c lib_lowsyslog.c
 CSRCS += lib_sprintf.c lib_asprintf.c lib_snprintf.c lib_libsprintf.c
 CSRCS += lib_vsprintf.c lib_avsprintf.c lib_vsnprintf.c lib_libvsprintf.c
 CSRCS += lib_dprintf.c lib_vdprintf.c
-CSRCS += lib_meminstream.c lib_memoutstream.c lib_lowinstream.c
-CSRCS += lib_lowoutstream.c lib_zeroinstream.c lib_nullinstream.c
-CSRCS += lib_nulloutstream.c lib_sscanf.c
+CSRCS += lib_meminstream.c lib_memoutstream.c lib_memsistream.c
+CSRCS += lib_memsostream.c lib_lowinstream.c lib_lowoutstream.c
+CSRCS += lib_zeroinstream.c lib_nullinstream.c lib_nulloutstream.c
+CSRCS += lib_sscanf.c
 
 # The remaining sources files depend upon file descriptors
 
@@ -78,7 +79,7 @@ CSRCS += lib_dtoa.c
 endif
 
 ifeq ($(CONFIG_STDIO_LINEBUFFER),y)
-CSRCS += lib_libnoflush.c
+CSRCS += lib_libnoflush.c lib_libsnoflush.c
 endif
 
 # Add the stdio directory to the build

libc/stdio/lib_libsnoflush.c

@@ -0,0 +1,104 @@
+/****************************************************************************
+ * libc/stdio/lib_libsnoflush.c
+ *
+ *   Copyright (C) 2014 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
+ * 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 <stdbool.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <errno.h>
+
+#include <nuttx/fs/fs.h>
+
+#include "lib_internal.h"
+
+#ifdef CONFIG_STDIO_LINEBUFFER
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Type Declarations
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Constant Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Constant Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: lib_snoflush
+ *
+ * Description:
+ *  lib_snoflush() provides a common, dummy flush method for seekable output
+ *  streams that are not flushable.  Only used if CONFIG_STDIO_LINEBUFFER
+ *  is selected.
+ *
+ * Return:
+ *  Always returns OK
+ *
+ ****************************************************************************/
+
+int lib_snoflush(FAR struct lib_sostream_s *this)
+{
+  return OK;
+}
+
+#endif /* CONFIG_STDIO_LINEBUFFER */
+

libc/stdio/lib_meminstream.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * libc/stdio/lib_meminstream.c
  *
- *   Copyright (C) 2007-2009, 2011-2012 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2009, 2011-2012, 2014 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -82,23 +82,23 @@ static int meminstream_getc(FAR struct lib_instream_s *this)
  *   Initializes a stream for use with a fixed-size memory buffer.
  *
  * Input parameters:
- *   meminstream - User allocated, uninitialized instance of struct
+ *   instream    - User allocated, uninitialized instance of struct
  *                 lib_meminstream_s to be initialized.
  *   bufstart    - Address of the beginning of the fixed-size memory buffer
  *   buflen      - Size of the fixed-sized memory buffer in bytes
  *
  * Returned Value:
- *   None (meminstream initialized).
+ *   None (instream initialized).
  *
  ****************************************************************************/
 
-void lib_meminstream(FAR struct lib_meminstream_s *meminstream,
+void lib_meminstream(FAR struct lib_meminstream_s *instream,
                      FAR const char *bufstart, int buflen)
 {
-  meminstream->public.get  = meminstream_getc;
-  meminstream->public.nget = 0;          /* Will be buffer index */
-  meminstream->buffer      = bufstart;   /* Start of buffer */
-  meminstream->buflen      = buflen;     /* Length of the buffer */
+  instream->public.get  = meminstream_getc;
+  instream->public.nget = 0;          /* Will be buffer index */
+  instream->buffer      = bufstart;   /* Start of buffer */
+  instream->buflen      = buflen;     /* Length of the buffer */
 }
 
 

libc/stdio/lib_memoutstream.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * libc/stdio/lib_memoutstream.c
  *
- *   Copyright (C) 2007-2009, 2011-2012 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2009, 2011-2012, 2014 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -79,27 +79,25 @@ static void memoutstream_putc(FAR struct lib_outstream_s *this, int ch)
  *   Initializes a stream for use with a fixed-size memory buffer.
  *
  * Input parameters:
- *   memoutstream - User allocated, uninitialized instance of struct
+ *   outstream - User allocated, uninitialized instance of struct
  *                  lib_memoutstream_s to be initialized.
  *   bufstart     - Address of the beginning of the fixed-size memory buffer
  *   buflen       - Size of the fixed-sized memory buffer in bytes
  *
  * Returned Value:
- *   None (memoutstream initialized).
+ *   None (outstream initialized).
  *
  ****************************************************************************/
 
-void lib_memoutstream(FAR struct lib_memoutstream_s *memoutstream,
+void lib_memoutstream(FAR struct lib_memoutstream_s *outstream,
                       FAR char *bufstart, int buflen)
 {
-  memoutstream->public.put   = memoutstream_putc;
+  outstream->public.put   = memoutstream_putc;
 #ifdef CONFIG_STDIO_LINEBUFFER
-  memoutstream->public.flush = lib_noflush;
+  outstream->public.flush = lib_noflush;
 #endif
-  memoutstream->public.nput  = 0;          /* Will be buffer index */
-  memoutstream->buffer       = bufstart;   /* Start of buffer */
-  memoutstream->buflen       = buflen - 1; /* Save space for null terminator */
-  memoutstream->buffer[0]    = '\0';       /* Start with an empty string */
+  outstream->public.nput  = 0;          /* Will be buffer index */
+  outstream->buffer       = bufstart;   /* Start of buffer */
+  outstream->buflen       = buflen - 1; /* Save space for null terminator */
+  outstream->buffer[0]    = '\0';       /* Start with an empty string */
 }
-
-

libc/stdio/lib_memsistream.c

@@ -0,0 +1,148 @@
+/****************************************************************************
+ * libc/stdio/lib_memsistream.c
+ *
+ *   Copyright (C) 2014 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
+ * 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 <assert.h>
+
+#include "lib_internal.h"
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: memsistream_getc
+ ****************************************************************************/
+
+static int memsistream_getc(FAR struct lib_sistream_s *this)
+{
+  FAR struct lib_memsistream_s *mthis = (FAR struct lib_memsistream_s *)this;
+  int ret;
+
+  DEBUGASSERT(this);
+
+  /* Get the next character (if any) from the buffer */
+
+  if (mthis->offset < mthis->buflen)
+    {
+      ret = mthis->buffer[mthis->offset];
+      mthis->offset++;
+      this->nget++;
+    }
+  else
+    {
+      ret = EOF;
+    }
+
+  return ret;
+}
+
+/****************************************************************************
+ * Name: memsistream_seek
+ ****************************************************************************/
+
+static off_t memsistream_seek(FAR struct lib_sistream_s *this, off_t offset,
+                              int whence)
+{
+  FAR struct lib_memsistream_s *mthis = (FAR struct lib_memsistream_s *)this;
+  off_t newpos;
+
+  DEBUGASSERT(this);
+
+  switch (whence)
+    {
+      case SEEK_CUR:
+        newpos = (off_t)mthis->offset + offset;
+        break;
+
+      case SEEK_SET:
+        newpos = offset;
+        break;
+
+      case SEEK_END:
+        newpos = (off_t)mthis->buflen + offset;
+        break;
+
+      default:
+        return (off_t)ERROR;
+    }
+
+  /* Make sure that the new position is within range */
+
+  if (newpos < 0 || newpos >= (off_t)mthis->buflen)
+    {
+      return (off_t)ERROR;
+    }
+
+  /* Return the new position */
+
+  mthis->offset = (size_t)newpos;
+  return newpos;
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: lib_memsistream
+ *
+ * Description:
+ *   Initializes a stream for use with a fixed-size memory buffer.
+ *
+ * Input parameters:
+ *   instream    - User allocated, uninitialized instance of struct
+ *                 lib_memsistream_s to be initialized.
+ *   bufstart    - Address of the beginning of the fixed-size memory buffer
+ *   buflen      - Size of the fixed-sized memory buffer in bytes
+ *
+ * Returned Value:
+ *   None (instream initialized).
+ *
+ ****************************************************************************/
+
+void lib_memsistream(FAR struct lib_memsistream_s *instream,
+                     FAR const char *bufstart, int buflen)
+{
+  instream->public.get  = memsistream_getc;
+  instream->public.seek = memsistream_seek;
+  instream->public.nget = 0;          /* Total number of characters read */
+  instream->buffer      = bufstart;   /* Start of buffer */
+  instream->offset      = 0;          /* Will be the buffer index */
+  instream->buflen      = buflen;     /* Length of the buffer */
+}

libc/stdio/lib_memsostream.c

@@ -0,0 +1,149 @@
+/****************************************************************************
+ * libc/stdio/lib_memsostream.c
+ *
+ *   Copyright (C) 2014 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
+ * 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 <assert.h>
+
+#include "lib_internal.h"
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: memsostream_putc
+ ****************************************************************************/
+
+static void memsostream_putc(FAR struct lib_sostream_s *this, int ch)
+{
+  FAR struct lib_memsostream_s *mthis = (FAR struct lib_memsostream_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 (mthis->offset < mthis->buflen)
+    {
+      mthis->buffer[mthis->offset] = ch;
+      mthis->offset++;
+      this->nput++;
+      mthis->buffer[mthis->offset] = '\0';
+    }
+}
+
+/****************************************************************************
+ * Name: memsostream_seek
+ ****************************************************************************/
+
+static off_t memsostream_seek(FAR struct lib_sostream_s *this, off_t offset,
+                              int whence)
+{
+  FAR struct lib_memsostream_s *mthis = (FAR struct lib_memsostream_s *)this;
+  off_t newpos;
+
+  DEBUGASSERT(this);
+
+  switch (whence)
+    {
+      case SEEK_CUR:
+        newpos = (off_t)mthis->offset + offset;
+        break;
+
+      case SEEK_SET:
+        newpos = offset;
+        break;
+
+      case SEEK_END:
+        newpos = (off_t)mthis->buflen + offset;
+        break;
+
+      default:
+        return (off_t)ERROR;
+    }
+
+  /* Make sure that the new position is within range */
+
+  if (newpos < 0 || newpos >= (off_t)mthis->buflen)
+    {
+      return (off_t)ERROR;
+    }
+
+  /* Return the new position */
+
+  mthis->offset = (size_t)newpos;
+  return newpos;
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: lib_memsostream
+ *
+ * Description:
+ *   Initializes a stream for use with a fixed-size memory buffer.
+ *
+ * Input parameters:
+ *   outstream - User allocated, uninitialized instance of struct
+ *                  lib_memsostream_s to be initialized.
+ *   bufstart     - Address of the beginning of the fixed-size memory buffer
+ *   buflen       - Size of the fixed-sized memory buffer in bytes
+ *
+ * Returned Value:
+ *   None (outstream initialized).
+ *
+ ****************************************************************************/
+
+void lib_memsostream(FAR struct lib_memsostream_s *outstream,
+                     FAR char *bufstart, int buflen)
+{
+  outstream->public.put   = memsostream_putc;
+#ifdef CONFIG_STDIO_LINEBUFFER
+  outstream->public.flush = lib_snoflush;
+#endif
+  outstream->public.seek  = memsostream_seek;
+  outstream->public.nput  = 0;          /* Total number of characters written */
+  outstream->buffer       = bufstart;   /* Start of buffer */
+  outstream->offset       = 0;          /* Will be the buffer index */
+  outstream->buflen       = buflen - 1; /* Save space for null terminator */
+  outstream->buffer[0]    = '\0';       /* Start with an empty string */
+}