Add asprintf()

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3652 42af7a65-404d-4744-a932-0658087f49c3

2 files changed, 138 insertions, 5 deletions

diff --git a/nuttx/lib/stdio/Make.defs b/nuttx/lib/stdio/Make.defs
index fe6e106bb..8515c5415 100644
--- a/nuttx/lib/stdio/Make.defs
+++ b/nuttx/lib/stdio/Make.defs
@@ -34,11 +34,11 @@
 ############################################################################
 
 STDIO_SRCS = lib_fileno.c lib_printf.c lib_rawprintf.c lib_lowprintf.c \
-		  lib_sprintf.c lib_snprintf.c lib_libsprintf.c lib_vsprintf.c \
-		  lib_vsnprintf.c lib_libvsprintf.c lib_meminstream.c \
-		  lib_memoutstream.c lib_lowinstream.c lib_lowoutstream.c \
-		  lib_zeroinstream.c lib_nullinstream.c lib_nulloutstream.c \
-		  lib_sscanf.c
+		  lib_sprintf.c lib_asprintf.c lib_snprintf.c lib_libsprintf.c \
+		  lib_vsprintf.c lib_vsnprintf.c lib_libvsprintf.c \
+		  lib_meminstream.c lib_memoutstream.c lib_lowinstream.c \
+		  lib_lowoutstream.c lib_zeroinstream.c lib_nullinstream.c \
+		  lib_nulloutstream.c lib_sscanf.c
 
 ifneq ($(CONFIG_NFILE_DESCRIPTORS),0)
 STDIO_SRCS += lib_rawinstream.c lib_rawoutstream.c
diff --git a/nuttx/lib/stdio/lib_asprintf.c b/nuttx/lib/stdio/lib_asprintf.c
new file mode 100644
index 000000000..2baffe1ac
--- /dev/null
+++ b/nuttx/lib/stdio/lib_asprintf.c
@@ -0,0 +1,133 @@
+/****************************************************************************
+ * lib/stdio/lib_asprintf.c
+ *
+ *   Copyright (C) 2011 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 <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
+
+#include "lib_internal.h"
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Type Declarations
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Constant Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Constant Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: asprintf
+ *
+ * Description:
+ *   This function is similar to sprintf, except that it dynamically
+ *   allocates a string (as with malloc) to hold the output, instead of
+ *   putting the output in a buffer you allocate in advance.  The ptr
+ *   argument should be the address of a char * object, and a successful
+ *   call to asprintf stores a pointer to the newly allocated string at that
+ *   location.
+ *
+ * Returned Value:
+ *   The returned value is the number of characters allocated for the buffer,
+ *   or less than zero if an error occurred. Usually this means that the buffer
+ *   could not be allocated.
+ *
+ ****************************************************************************/
+
+int asprintf (FAR char **ptr, const char *fmt, ...)
+{
+  struct lib_outstream_s nulloutstream;
+  struct lib_memoutstream_s memoutstream;
+  FAR char *buf;
+  va_list ap;
+  int     n;
+
+  /* First, use a nullstream to get the size of the buffer */
+  
+  lib_nulloutstream(&nulloutstream);
+  va_start(ap, fmt);
+  n = lib_vsprintf((FAR struct lib_outstream_s *)&nulloutstream, fmt, ap);
+  va_end(ap);
+
+  /* Then allocate a buffer to hold that number of characters */
+
+  buf = (FAR char *)malloc(nulloutstream.nput + 1);
+  if (!buf)
+    {
+      return ERROR;
+    }
+
+  /* Initialize a memory stream to write into the allocated buffer */
+
+  lib_memoutstream((FAR struct lib_memoutstream_s *)&memoutstream,
+                   buf, nulloutstream.nput);
+
+  /* Then let lib_vsprintf do it real thing */
+
+  va_start(ap, fmt);
+  n = lib_vsprintf((FAR struct lib_outstream_s *)&memoutstream.public, fmt, ap);
+  va_end(ap);
+
+  DEBUGASSERT(n < 0 || n == nulloutstream.nput);
+  buf[nulloutstream.nput] = '\0';
+  return n;
+}