Add asprintf() implementation for platforms without it

Provides a portable implementation of this common allocating sprintf()
API found in many, but not yet all, of the platforms we support.
If the platform provides vasprintf() we simply wrap it, otherwise we
implement it - either way callers can use it regardless of platform.

Since not all platforms guarantee to NULL out the return pointer on
failure, we don't either, and require callers to check the return
value for -1.

The old Xprintf() API is deprecated, but left for compatibility for now.

The new API is added in a new header so that it can be used in parts of
the server such as hw/xfree86/parser that don't include all the server
headers.

Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Reviewed-by: Mikhail Gusarov <dottedmag@dottedmag.net>

4 files changed, 81 insertions, 4 deletions

diff --git a/include/Makefile.am b/include/Makefile.am
index 966d21525..42f008269 100644
--- a/include/Makefile.am
+++ b/include/Makefile.am
@@ -1,6 +1,7 @@
 if XORG
 sdk_HEADERS =		\
 	XIstubs.h	\
+	Xprintf.h	\
 	callback.h	\
 	closestr.h	\
 	closure.h	\
diff --git a/include/Xprintf.h b/include/Xprintf.h
new file mode 100644
index 000000000..5177122c9
--- /dev/null
+++ b/include/Xprintf.h
@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef XPRINTF_H
+#define XPRINTF_H
+
+#include <stdio.h>
+#include <stdarg.h>
+#include <X11/Xfuncproto.h>
+
+#ifndef _X_RESTRICT_KYWD
+# if defined(restrict) /* assume autoconf set it correctly */ || \
+   (defined(__STDC__) && (__STDC_VERSION__ - 0 >= 199901L)) /* C99 */
+#  define _X_RESTRICT_KYWD  restrict
+# elif defined(__GNUC__) && !defined(__STRICT_ANSI__) /* gcc w/C89+extensions */
+#  define _X_RESTRICT_KYWD __restrict__
+# else
+#  define _X_RESTRICT_KYWD
+# endif
+#endif
+
+/*
+ * These functions provide a portable implementation of the common (but not
+ * yet universal) asprintf & vasprintf routines to allocate a buffer big
+ * enough to sprintf the arguments to.  The XNF variants terminate the server
+ * if the allocation fails.
+ * The buffer allocated is returned in the pointer provided in the first
+ * argument.   The return value is the size of the allocated buffer, or -1
+ * on failure.
+ */
+extern _X_EXPORT int Xasprintf (char **ret,
+				const char * _X_RESTRICT_KYWD fmt,
+				...) _X_ATTRIBUTE_PRINTF(2,3);
+extern _X_EXPORT int Xvasprintf (char **ret,
+				 const char * _X_RESTRICT_KYWD fmt,
+				 va_list va) _X_ATTRIBUTE_PRINTF(2,0);
+extern _X_EXPORT int XNFasprintf (char **ret,
+				  const char * _X_RESTRICT_KYWD fmt,
+				  ...) _X_ATTRIBUTE_PRINTF(2,3);
+extern _X_EXPORT int XNFvasprintf (char **ret,
+				   const char * _X_RESTRICT_KYWD fmt,
+				   va_list va) _X_ATTRIBUTE_PRINTF(2,0);
+
+#if !defined(HAVE_ASPRINTF) && !defined(HAVE_VASPRINTF)
+# define asprintf  Xasprintf
+# define vasprintf Xvasprintf
+#endif
+
+#endif /* XPRINTF_H */
diff --git a/include/dix-config.h.in b/include/dix-config.h.in
index 6a332642b..5622766b8 100644
--- a/include/dix-config.h.in
+++ b/include/dix-config.h.in
@@ -243,6 +243,9 @@
 /* Define to 1 if you have the `vprintf' function. */
 #undef HAVE_VPRINTF
 
+/* Define to 1 if you have the `vasprintf' function. */
+#undef HAVE_VASPRINTF
+
 /* Support IPv6 for TCP connections */
 #undef IPv6
 
diff --git a/include/os.h b/include/os.h
index 566514d4a..88f23aeed 100644
--- a/include/os.h
+++ b/include/os.h
@@ -263,10 +263,14 @@ extern _X_EXPORT char *Xstrdup(const char *s);
  */
 extern _X_EXPORT char *XNFstrdup(const char *s);
 
-extern _X_EXPORT char *Xprintf(const char *fmt, ...) _X_ATTRIBUTE_PRINTF(1,2);
-extern _X_EXPORT char *Xvprintf(const char *fmt, va_list va);
-extern _X_EXPORT char *XNFprintf(const char *fmt, ...) _X_ATTRIBUTE_PRINTF(1,2);
-extern _X_EXPORT char *XNFvprintf(const char *fmt, va_list va);
+/* Include new X*asprintf API */
+#include "Xprintf.h"
+
+/* Older api deprecated in favor of the asprintf versions */
+extern _X_EXPORT char *Xprintf(const char *fmt, ...) _X_ATTRIBUTE_PRINTF(1,2) _X_DEPRECATED;
+extern _X_EXPORT char *Xvprintf(const char *fmt, va_list va)_X_ATTRIBUTE_PRINTF(1,0) _X_DEPRECATED;
+extern _X_EXPORT char *XNFprintf(const char *fmt, ...) _X_ATTRIBUTE_PRINTF(1,2) _X_DEPRECATED;
+extern _X_EXPORT char *XNFvprintf(const char *fmt, va_list va)_X_ATTRIBUTE_PRINTF(1,0) _X_DEPRECATED;
 
 typedef void (*OsSigHandlerPtr)(int /* sig */);
 typedef int (*OsSigWrapperPtr)(int /* sig */);