* stdio-common/printf.h (struct printf_info): Add user element.

	New types printf_arginfo_size_function, printf_va_arg_function.
	Declare register_printf_specifier, register_printf_modifier,
	register_printf_type.
	* stdio-common/printf-parse.h (struct printf_spec): Add size element.
	(union printf_arg): Add pa_user element.
	Adjust __printf_arginfo_table type.
	Add __printf_va_arg_table, __printf_modifier_table,
	__handle_registered_modifier_mb, and __handle_registered_modifier_wc
	declarations.
	* stdio-common/printf-parsemb.c: Recognize registered modifiers.
	If registered arginfo call failed try normal specifier.
	* stdio-common/printf-prs.c: Pass additional parameter to arginfo
	function.
	* stdio-common/Makefile (routines): Add reg-modifier and reg-type.
	* stdio-common/Versions: Export register_printf_modifier,
	register_printf_type, and register_printf_specifier for GLIBC_2.10.
	* stdio-common/reg-modifier.c: New file.
	* stdio-common/reg-type.c: New file.
	* stdio-common/reg-printf.c (__register_printf_specifier): New
	function.  Mostly the old __register_printf_function function but
	uses locking and type of third parameter changed.
	(__register_printf_function): Implement using
	__register_printf_specifier.
	* stdio-common/vfprintf.c (vfprintf): Collect argument sizes in
	calls to arginfo functions.  Allocate enough memory for user-defined
	types.  Call new va_arg functions to get user-defined types.
	Try installed handlers even for existing format specifiers first.

ChangeLog

@@ -1,3 +1,34 @@
+2009-04-10  Ulrich Drepper  <drepper@redhat.com>
+
+	* stdio-common/printf.h (struct printf_info): Add user element.
+	New types printf_arginfo_size_function, printf_va_arg_function.
+	Declare register_printf_specifier, register_printf_modifier,
+	register_printf_type.
+	* stdio-common/printf-parse.h (struct printf_spec): Add size element.
+	(union printf_arg): Add pa_user element.
+	Adjust __printf_arginfo_table type.
+	Add __printf_va_arg_table, __printf_modifier_table,
+	__handle_registered_modifier_mb, and __handle_registered_modifier_wc
+	declarations.
+	* stdio-common/printf-parsemb.c: Recognize registered modifiers.
+	If registered arginfo call failed try normal specifier.
+	* stdio-common/printf-prs.c: Pass additional parameter to arginfo
+	function.
+	* stdio-common/Makefile (routines): Add reg-modifier and reg-type.
+	* stdio-common/Versions: Export register_printf_modifier,
+	register_printf_type, and register_printf_specifier for GLIBC_2.10.
+	* stdio-common/reg-modifier.c: New file.
+	* stdio-common/reg-type.c: New file.
+	* stdio-common/reg-printf.c (__register_printf_specifier): New
+	function.  Mostly the old __register_printf_function function but
+	uses locking and type of third parameter changed.
+	(__register_printf_function): Implement using
+	__register_printf_specifier.
+	* stdio-common/vfprintf.c (vfprintf): Collect argument sizes in
+	calls to arginfo functions.  Allocate enough memory for user-defined
+	types.  Call new va_arg functions to get user-defined types.
+	Try installed handlers even for existing format specifiers first.
+
 2009-04-09  Ulrich Drepper  <drepper@redhat.com>
 
 	* sysdeps/x86_64/rawmemchr.S: New file.

NEWS

@@ -1,4 +1,4 @@
-GNU C Library NEWS -- history of user-visible changes.  2009-4-8
+GNU C Library NEWS -- history of user-visible changes.  2009-4-10
 Copyright (C) 1992-2008, 2009 Free Software Foundation, Inc.
 See the end for copying conditions.
 
@@ -37,7 +37,11 @@ Version 2.10
 
 * New locales: nan_TW@latin, ks_IN
 
-* Faster strlen, strchr, strchrnul, and memchr for x86-64.
+* Faster strlen, strchr, strchrnul, memchr, and rawmemchr for x86-64.
+  Implemented by Ulrich Drepper.
+
+* Extended printf hook support.  It is possible to use user-defined types
+  and extend existing format specifiers.
   Implemented by Ulrich Drepper.
 
 

stdio-common/Makefile

@@ -27,6 +27,7 @@ routines	:=							      \
 	ctermid cuserid							      \
 	_itoa _itowa itoa-digits itoa-udigits itowa-digits		      \
 	vfprintf vprintf printf_fp reg-printf printf-prs printf_fphex	      \
+	reg-modifier reg-type						      \
 	printf_size fprintf printf snprintf sprintf asprintf dprintf	      \
 	vfwprintf vfscanf vfwscanf					      \
 	fscanf scanf sscanf						      \

stdio-common/Versions

@@ -55,6 +55,7 @@ libc {
   }
   GLIBC_2.10 {
     psiginfo;
+    register_printf_modifier; register_printf_type; register_printf_specifier;
   }
   GLIBC_PRIVATE {
     # global variables

stdio-common/printf-parse.h

@@ -1,5 +1,5 @@
 /* Internal header for parsing printf format strings.
-   Copyright (C) 1995-1999, 2000, 2002, 2003, 2007
+   Copyright (C) 1995-1999, 2000, 2002, 2003, 2007, 2009
    Free Software Foundation, Inc.
    This file is part of th GNU C Library.
 
@@ -42,6 +42,8 @@ struct printf_spec
     int data_arg_type;		/* Type of first argument.  */
     /* Number of arguments consumed by this format specifier.  */
     size_t ndata_args;
+    /* Size of the parameter for PA_USER type.  */
+    int size;
   };
 
 
@@ -60,6 +62,7 @@ union printf_arg
     const char *pa_string;
     const wchar_t *pa_wstring;
     void *pa_pointer;
+    void *pa_user;
   };
 
 
@@ -83,8 +86,9 @@ read_int (const UCHAR_T * *pstr)
 
 
 /* These are defined in reg-printf.c.  */
-extern printf_arginfo_function **__printf_arginfo_table attribute_hidden;
+extern printf_arginfo_size_function **__printf_arginfo_table attribute_hidden;
 extern printf_function **__printf_function_table attribute_hidden;
+extern printf_va_arg_function **__printf_va_arg_table attribute_hidden;
 
 
 /* Find the next spec in FORMAT, or the end of the string.  Returns
@@ -114,3 +118,18 @@ extern size_t __parse_one_specmb (const unsigned char *format, size_t posn,
 extern size_t __parse_one_specwc (const unsigned int *format, size_t posn,
 				  struct printf_spec *spec,
 				  size_t *max_ref_arg) attribute_hidden;
+
+
+
+/* This variable is defined in reg-modifier.c.  */
+struct printf_modifier_record;
+extern struct printf_modifier_record **__printf_modifier_table
+     attribute_hidden;
+
+/* Handle registered modifiers.  */
+extern int __handle_registered_modifier_mb (const unsigned char **format,
+					    struct printf_info *info)
+     attribute_hidden;
+extern int __handle_registered_modifier_wc (const unsigned int **format,
+					    struct printf_info *info)
+     attribute_hidden;

stdio-common/printf-parsemb.c

@@ -1,5 +1,5 @@
 /* Helper functions for parsing printf format strings.
-   Copyright (C) 1995-2000,2002,2003,2004,2006 Free Software Foundation, Inc.
+   Copyright (C) 1995-2000,2002-2004,2006,2009 Free Software Foundation, Inc.
    This file is part of th GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -31,12 +31,14 @@
 # define INT_T		int
 # define L_(Str)	Str
 # define ISDIGIT(Ch)	isdigit (Ch)
+# define HANDLE_REGISTERED_MODIFIER __handle_registered_modifier_mb
 #else
 # define CHAR_T		wchar_t
 # define UCHAR_T	unsigned int
 # define INT_T		wint_t
 # define L_(Str)	L##Str
 # define ISDIGIT(Ch)	iswdigit (Ch)
+# define HANDLE_REGISTERED_MODIFIER __handle_registered_modifier_wc
 #endif
 
 #include "printf-parse.h"
@@ -223,72 +225,79 @@ __parse_one_specmb (const UCHAR_T *format, size_t posn,
   spec->info.is_short = 0;
   spec->info.is_long = 0;
   spec->info.is_char = 0;
-
-  switch (*format++)
-    {
-    case L_('h'):
-      /* ints are short ints or chars.  */
-      if (*format != L_('h'))
-	spec->info.is_short = 1;
-      else
-	{
-	  ++format;
-	  spec->info.is_char = 1;
-	}
-      break;
-    case L_('l'):
-      /* ints are long ints.  */
-      spec->info.is_long = 1;
-      if (*format != L_('l'))
+  spec->info.user = 0;
+
+  if (__builtin_expect (__printf_modifier_table == NULL, 1)
+      || __printf_modifier_table[*format] == NULL
+      || HANDLE_REGISTERED_MODIFIER (&format, &spec->info) != 0)
+    switch (*format++)
+      {
+      case L_('h'):
+	/* ints are short ints or chars.  */
+	if (*format != L_('h'))
+	  spec->info.is_short = 1;
+	else
+	  {
+	    ++format;
+	    spec->info.is_char = 1;
+	  }
 	break;
-      ++format;
-      /* FALLTHROUGH */
-    case L_('L'):
-      /* doubles are long doubles, and ints are long long ints.  */
-    case L_('q'):
-      /* 4.4 uses this for long long.  */
-      spec->info.is_long_double = 1;
-      break;
-    case L_('z'):
-    case L_('Z'):
-      /* ints are size_ts.  */
-      assert (sizeof (size_t) <= sizeof (unsigned long long int));
+      case L_('l'):
+	/* ints are long ints.  */
+	spec->info.is_long = 1;
+	if (*format != L_('l'))
+	  break;
+	++format;
+	/* FALLTHROUGH */
+      case L_('L'):
+	/* doubles are long doubles, and ints are long long ints.  */
+      case L_('q'):
+	/* 4.4 uses this for long long.  */
+	spec->info.is_long_double = 1;
+	break;
+      case L_('z'):
+      case L_('Z'):
+	/* ints are size_ts.  */
+	assert (sizeof (size_t) <= sizeof (unsigned long long int));
 #if LONG_MAX != LONG_LONG_MAX
-      spec->info.is_long_double = sizeof (size_t) > sizeof (unsigned long int);
+	spec->info.is_long_double = (sizeof (size_t)
+				     > sizeof (unsigned long int));
 #endif
-      spec->info.is_long = sizeof (size_t) > sizeof (unsigned int);
-      break;
-    case L_('t'):
-      assert (sizeof (ptrdiff_t) <= sizeof (long long int));
+	spec->info.is_long = sizeof (size_t) > sizeof (unsigned int);
+	break;
+      case L_('t'):
+	assert (sizeof (ptrdiff_t) <= sizeof (long long int));
 #if LONG_MAX != LONG_LONG_MAX
-      spec->info.is_long_double = (sizeof (ptrdiff_t) > sizeof (long int));
+	spec->info.is_long_double = (sizeof (ptrdiff_t) > sizeof (long int));
 #endif
-      spec->info.is_long = sizeof (ptrdiff_t) > sizeof (int);
-      break;
-    case L_('j'):
-      assert (sizeof (uintmax_t) <= sizeof (unsigned long long int));
+	spec->info.is_long = sizeof (ptrdiff_t) > sizeof (int);
+	break;
+      case L_('j'):
+	assert (sizeof (uintmax_t) <= sizeof (unsigned long long int));
 #if LONG_MAX != LONG_LONG_MAX
-      spec->info.is_long_double = (sizeof (uintmax_t)
-				   > sizeof (unsigned long int));
+	spec->info.is_long_double = (sizeof (uintmax_t)
+				     > sizeof (unsigned long int));
 #endif
-      spec->info.is_long = sizeof (uintmax_t) > sizeof (unsigned int);
-      break;
-    default:
-      /* Not a recognized modifier.  Backup.  */
-      --format;
-      break;
-    }
+	spec->info.is_long = sizeof (uintmax_t) > sizeof (unsigned int);
+	break;
+      default:
+	/* Not a recognized modifier.  Backup.  */
+	--format;
+	break;
+      }
 
   /* Get the format specification.  */
   spec->info.spec = (wchar_t) *format++;
-  if (__builtin_expect (__printf_function_table != NULL, 0)
-      && spec->info.spec <= UCHAR_MAX
-      && __printf_arginfo_table[spec->info.spec] != NULL)
-    /* We don't try to get the types for all arguments if the format
-       uses more than one.  The normal case is covered though.  */
-    spec->ndata_args = (*__printf_arginfo_table[spec->info.spec])
-      (&spec->info, 1, &spec->data_arg_type);
-  else
+  spec->size = -1;
+  if (__builtin_expect (__printf_function_table == NULL, 1)
+      || spec->info.spec > UCHAR_MAX
+      || __printf_arginfo_table[spec->info.spec] == NULL
+      /* We don't try to get the types for all arguments if the format
+	 uses more than one.  The normal case is covered though.  If
+	 the call returns -1 we continue with the normal specifiers.  */
+      || (spec->ndata_args = (*__printf_arginfo_table[spec->info.spec])
+	  (&spec->info, 1, &spec->data_arg_type,
+	   &spec->size)) < 0)
     {
       /* Find the data argument types of a built-in spec.  */
       spec->ndata_args = 1;

stdio-common/printf-prs.c

@@ -1,5 +1,5 @@
-/* Copyright (C) 1991, 1992, 1995, 1996, 1999, 2000, 2002, 2003, 2004, 2005,
-   2007 Free Software Foundation, Inc.
+/* Copyright (C) 1991, 1992, 1995, 1996, 1999, 2000, 2002-2005, 2007, 2009
+   Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -97,7 +97,8 @@ parse_printf_format (fmt, n, argtypes)
 	    /* We have more than one argument for this format spec.  We must
                call the arginfo function again to determine all the types.  */
 	    (void) (*__printf_arginfo_table[spec.info.spec])
-	      (&spec.info, n - spec.data_arg, &argtypes[spec.data_arg]);
+	      (&spec.info, n - spec.data_arg, &argtypes[spec.data_arg],
+	       &spec.size);
 	    break;
 	  }
     }

stdio-common/printf.h

@@ -1,4 +1,4 @@
-/* Copyright (C) 1991-1993,1995-1999,2000,2001,2006
+/* Copyright (C) 1991-1993,1995-2001,2006,2009
 	Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -29,6 +29,7 @@ __BEGIN_DECLS
 #define	__need_size_t
 #define __need_wchar_t
 #include <stddef.h>
+#include <stdarg.h>
 
 
 struct printf_info
@@ -48,6 +49,8 @@ struct printf_info
   unsigned int is_char:1;	/* hh flag.  */
   unsigned int wide:1;		/* Nonzero for wide character streams.  */
   unsigned int i18n:1;		/* I flag.  */
+  unsigned int __pad:4;		/* Unused so far.  */
+  unsigned short int user;	/* Bits for user-installed modifiers.  */
   wchar_t pad;			/* Padding character.  */
 };
 
@@ -68,18 +71,55 @@ typedef int printf_function (FILE *__stream,
 
 /* Type of a printf specifier-arginfo function.
    INFO gives information about the format specification.
-   N, ARGTYPES, and return value are as for parse_printf_format.  */
+   N, ARGTYPES, *SIZE has to contain the size of the parameter for
+   user-defined types, and return value are as for parse_printf_format
+   except that -1 should be returned if the handler cannot handle
+   this case.  This allows to partially overwrite the functionality
+   of existing format specifiers.  */
+
+typedef int printf_arginfo_size_function (__const struct printf_info *__info,
+					  size_t __n, int *__argtypes,
+					  int *__size);
+
+/* Old version of 'printf_arginfo_function' without a SIZE parameter.  */
 
 typedef int printf_arginfo_function (__const struct printf_info *__info,
 				     size_t __n, int *__argtypes);
 
+/* Type of a function to get a value of a user-defined from the
+   variable argument list.  */
+typedef void printf_va_arg_function (void *__mem, va_list *__ap);
+
 
 /* Register FUNC to be called to format SPEC specifiers; ARGINFO must be
    specified to determine how many arguments a SPEC conversion requires and
    what their types are.  */
 
+extern int register_printf_specifier (int __spec, printf_function __func,
+				      printf_arginfo_size_function __arginfo)
+  __THROW;
+
+
+/* Obsolete interface similar to register_printf_specifier.  It can only
+   handle basic data types because the ARGINFO callback does not return
+   information on the size of the user-defined type.  */
+
 extern int register_printf_function (int __spec, printf_function __func,
-				     printf_arginfo_function __arginfo);
+				     printf_arginfo_function __arginfo)
+  __THROW __attribute_deprecated__;
+
+
+/* Register a new modifier character sequence.  If the call succeeds
+   it returns a positive value representing the bit set in the USER
+   field in 'struct printf_info'.  */
+
+extern int register_printf_modifier (wchar_t *__str) __wur __THROW;
+
+
+/* Register variable argument handler for user type.  The return value
+   is to be used in ARGINFO functions to signal the use of the
+   type.  */
+extern int register_printf_type (printf_va_arg_function __fct) __wur __THROW;
 
 
 /* Parse FMT, and fill in N elements of ARGTYPES with the
@@ -100,7 +140,8 @@ extern size_t parse_printf_format (__const char *__restrict __fmt, size_t __n,
 /* Codes returned by `parse_printf_format' for basic types.
 
    These values cover all the standard format specifications.
-   Users can add new values after PA_LAST for their own types.  */
+   Users can reserve new values after PA_LAST for their own types
+   using 'register_printf_type'.  */
 
 enum
 {				/* C type: */