Re: [PATCH] Hide internal printf functions [BZ #18822/21986]

["H.J. Lu" <hjl dot tools at gmail dot com>]

On Mon, Aug 21, 2017 at 11:33 PM, Andreas Schwab <schwab@suse.de> wrote:
> On Aug 21 2017, "H.J. Lu" <hongjiu.lu@intel.com> wrote:
>
>> diff --git a/stdio-common/printf.h b/stdio-common/printf.h
>> index 940256445e..155dfdc7d3 100644
>> --- a/stdio-common/printf.h
>> +++ b/stdio-common/printf.h
>> @@ -182,6 +182,9 @@ extern int printf_size_info (const struct printf_info *__restrict
>>                            __info, size_t __n, int *__restrict __argtypes)
>>       __THROW;
>>
>> +extern unsigned int __guess_grouping (unsigned int intdig_max,
>> +                                   const char *grouping);
>> +
>
> This is not a public function.
>

Here is the updated patch to move __guess_grouping prototype to
include/printf.h.  OK for master?

-- 
H.J.

From 9756b67d83c5436fec5d8fa17125529d4ad02ac9 Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Mon, 21 Aug 2017 14:37:11 -0700
Subject: [PATCH] Hide internal printf functions [BZ #18822/21986]

Hide internal printf functions to allow direct access within libc.so and
libc.a without using GOT nor PLT.

Since __guess_grouping has been changed to take 2 arguments by

commit a1d84548c8aa7023cd039c85f81b831eef6d4a4c
Author: Ulrich Drepper <drepper@redhat.com>
Date:   Fri Feb 11 18:50:36 2000 +0000

the third argument passed to __guess_grouping is removed.

	[BZ #18822]
	[BZ #21986]
	* include/printf.h (__printf_fphex): Add attribute_hidden.
	(__guess_grouping): New prototype.
	* stdio-common/printf_fp.c (__guess_grouping): Removed.
	* stdio-common/reg-printf.c (__register_printf_specifier): Add
	libc_hidden_proto and libc_hidden_def.
	* stdlib/strfmon_l.c (__guess_grouping): Removed.
	(__vstrfmon_l): Remove the third argument passed to
	__guess_grouping.
---
 include/printf.h          | 6 +++++-
 stdio-common/printf_fp.c  | 2 --
 stdio-common/reg-printf.c | 2 ++
 stdlib/strfmon_l.c        | 9 +--------
 4 files changed, 8 insertions(+), 11 deletions(-)

diff --git a/include/printf.h b/include/printf.h
index 7b4d209c47..d051514119 100644
--- a/include/printf.h
+++ b/include/printf.h
@@ -8,7 +8,7 @@
 
 /* Now define the internal interfaces.  */
 extern int __printf_fphex (FILE *, const struct printf_info *,
-			   const void *const *);
+			   const void *const *) attribute_hidden;
 extern int __printf_fp (FILE *, const struct printf_info *,
 			const void *const *);
 libc_hidden_proto (__printf_fp)
@@ -16,5 +16,9 @@ extern int __printf_fp_l (FILE *, locale_t, const struct printf_info *,
 			  const void *const *);
 libc_hidden_proto (__printf_fp_l)
 
+extern unsigned int __guess_grouping (unsigned int intdig_max,
+				      const char *grouping)
+     attribute_hidden;
+
 # endif /* !_ISOMAC */
 #endif
diff --git a/stdio-common/printf_fp.c b/stdio-common/printf_fp.c
index 3ed4037ba5..2633a02cc5 100644
--- a/stdio-common/printf_fp.c
+++ b/stdio-common/printf_fp.c
@@ -139,8 +139,6 @@ extern mp_size_t __mpn_extract_double (mp_ptr res_ptr, mp_size_t size,
 extern mp_size_t __mpn_extract_long_double (mp_ptr res_ptr, mp_size_t size,
 					    int *expt, int *is_neg,
 					    long double value);
-extern unsigned int __guess_grouping (unsigned int intdig_max,
-				      const char *grouping);
 
 
 static wchar_t *group_number (wchar_t *buf, wchar_t *bufend,
diff --git a/stdio-common/reg-printf.c b/stdio-common/reg-printf.c
index cbb9307795..fed5a16a7b 100644
--- a/stdio-common/reg-printf.c
+++ b/stdio-common/reg-printf.c
@@ -32,6 +32,7 @@ __libc_lock_define_initialized (static, lock)
 
 int __register_printf_specifier (int, printf_function,
 				 printf_arginfo_size_function);
+libc_hidden_proto (__register_printf_specifier)
 int __register_printf_function (int, printf_function,
 				printf_arginfo_function);
 
@@ -72,6 +73,7 @@ __register_printf_specifier (int spec, printf_function converter,
 
   return result;
 }
+libc_hidden_def (__register_printf_specifier)
 weak_alias (__register_printf_specifier, register_printf_specifier)
 
 
diff --git a/stdlib/strfmon_l.c b/stdlib/strfmon_l.c
index 98554dfe80..1df184e8b2 100644
--- a/stdlib/strfmon_l.c
+++ b/stdlib/strfmon_l.c
@@ -68,11 +68,6 @@
 #define _NL_CURRENT(category, item) \
   (current->values[_NL_ITEM_INDEX (item)].string)
 
-/* This function determines the number of digit groups in the output.
-   The definition is in printf_fp.c.  */
-extern unsigned int __guess_grouping (unsigned int intdig_max,
-				      const char *grouping, wchar_t sepchar);
-
 
 /* We have to overcome some problems with this implementation.  On the
    one hand the strfmon() function is specified in XPG4 and of course
@@ -324,9 +319,7 @@ __vstrfmon_l (char *s, size_t maxsize, locale_t loc, const char *format,
 	 extra characters this means.  */
       if (group && left_prec != -1)
 	left_prec += __guess_grouping (left_prec,
-				       _NL_CURRENT (LC_MONETARY, MON_GROUPING),
-				       *_NL_CURRENT (LC_MONETARY,
-						     MON_THOUSANDS_SEP));
+				       _NL_CURRENT (LC_MONETARY, MON_GROUPING));
 
       /* Now it's time to get the value.  */
       if (is_long_double == 1)
-- 
2.13.5