glibc/stdlib/strfrom-skeleton.c
Zack Weinberg 698fb75b9f Add __v*printf_internal with flags arguments
There are a lot more printf variants than there are scanf variants,
and the code for setting up and tearing down their custom FILE
variants around the call to __vf(w)printf is more complicated and
variable.  Therefore, I have added _internal versions of all the
v*printf variants, rather than introducing helper routines so that
they can all directly call __vf(w)printf_internal, as was done with
scanf.

As with the scanf changes, in this patch the _internal functions still
look at the environmental mode bits and all callers pass 0 for the
flags parameter.

Several of the affected public functions had _IO_ name aliases that
were not exported (but, in one case, appeared in libio.h anyway);
I was originally planning to leave them as aliases to avoid having
to touch internal callers, but it turns out ldbl_*_alias only work
for exported symbols, so they've all been removed instead.  It also
turns out there were hardly any internal callers.  _IO_vsprintf and
_IO_vfprintf *are* exported, so those two stick around.

Summary for the changes to each of the affected symbols:

  _IO_vfprintf, _IO_vsprintf:
    All internal calls removed, thus the internal declarations, as well
    as uses of libc_hidden_proto and libc_hidden_def, were also removed.
    The external symbol is now exposed via uses of ldbl_strong_alias
    to __vfprintf_internal and __vsprintf_internal, respectively.

  _IO_vasprintf, _IO_vdprintf, _IO_vsnprintf,
  _IO_vfwprintf, _IO_vswprintf,
  _IO_obstack_vprintf, _IO_obstack_printf:
    All internal calls removed, thus declaration in internal headers
    were also removed.  They were never exported, so there are no
    aliases tying them to the internal functions.  I.e.: entirely gone.

  __vsnprintf:
    Internal calls were always preceded by macros such as
      #define __vsnprintf _IO_vsnprintf, and
      #define __vsnprintf vsnprintf
    The macros were removed and their uses replaced with calls to the
    new internal function __vsnprintf_internal.  Since there were no
    internal calls, the internal declaration was also removed.  The
    external symbol is preserved with ldbl_weak_alias to ___vsnprintf.

  __vfwprintf:
    All internal calls converted into calls to __vfwprintf_internal,
    thus the internal declaration was removed.  The function is now a
    wrapper that calls __vfwprintf_internal.  The external symbol is
    preserved.

  __vswprintf:
    Similarly, but no external symbol.

  __vasprintf, __vdprintf, __vfprintf, __vsprintf:
    New internal wrappers.  Not exported.

  vasprintf, vdprintf, vfprintf, vsprintf, vsnprintf,
  vfwprintf, vswprintf,
  obstack_vprintf, obstack_printf:
    These functions used to be aliases to the respective _IO_* function,
    they are now aliases to their respective __* functions.

Tested for powerpc and powerpc64le.
2018-12-05 18:15:42 -02:00

156 lines
4.9 KiB
C

/* Convert a floating-point number to string.
Copyright (C) 2016-2018 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
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
/* Generic implementation for strfrom functions. The implementation is generic
for several floating-point types (e.g.: float, double), so that each
function, such as strfromf and strfroml, share the same code, thus avoiding
code duplication. */
#include <ctype.h>
#include "../libio/libioP.h"
#include "../libio/strfile.h"
#include <printf.h>
#include <string.h>
#include <locale/localeinfo.h>
#define UCHAR_T char
#define L_(Str) Str
#define ISDIGIT(Ch) isdigit (Ch)
#include "stdio-common/printf-parse.h"
int
STRFROM (char *dest, size_t size, const char *format, FLOAT f)
{
_IO_strnfile sfile;
#ifdef _IO_MTSAFE_IO
sfile.f._sbf._f._lock = NULL;
#endif
int done;
/* Single-precision values need to be stored in a double type, because
__printf_fp_l and __printf_fphex do not accept the float type. */
union {
double flt;
FLOAT value;
} fpnum;
const void *fpptr;
fpptr = &fpnum;
/* Variables to control the output format. */
int precision = -1; /* printf_fp and printf_fphex treat this internally. */
int specifier;
struct printf_info info;
/* Single-precision values need to be converted into double-precision,
because __printf_fp and __printf_fphex only accept double and long double
as the floating-point argument. */
if (__builtin_types_compatible_p (FLOAT, float))
fpnum.flt = f;
else
fpnum.value = f;
/* Check if the first character in the format string is indeed the '%'
character. Otherwise, abort. */
if (*format == '%')
format++;
else
abort ();
/* The optional precision specification always starts with a '.'. If such
character is present, read the precision. */
if (*format == '.')
{
format++;
/* Parse the precision. */
if (ISDIGIT (*format))
precision = read_int (&format);
/* If only the period is specified, the precision is taken as zero, as
described in ISO/IEC 9899:2011, section 7.21.6.1, 4th paragraph, 3rd
item. */
else
precision = 0;
}
/* Now there is only the conversion specifier to be read. */
switch (*format)
{
case 'a':
case 'A':
case 'e':
case 'E':
case 'f':
case 'F':
case 'g':
case 'G':
specifier = *format;
break;
default:
abort ();
}
/* The following code to prepare the virtual file has been adapted from the
function __vsnprintf_internal from libio. */
if (size == 0)
{
/* When size is zero, nothing is written and dest may be a null pointer.
This is specified for snprintf in ISO/IEC 9899:2011, Section 7.21.6.5,
in the second paragraph. Thus, if size is zero, prepare to use the
overflow buffer right from the start. */
dest = sfile.overflow_buf;
size = sizeof (sfile.overflow_buf);
}
/* Prepare the virtual string file. */
_IO_no_init (&sfile.f._sbf._f, _IO_USER_LOCK, -1, NULL, NULL);
_IO_JUMPS (&sfile.f._sbf) = &_IO_strn_jumps;
_IO_str_init_static_internal (&sfile.f, dest, size - 1, dest);
/* Prepare the format specification for printf_fp. */
memset (&info, '\0', sizeof (info));
/* The functions strfromd and strfromf pass a floating-point number with
double precision to printf_fp, whereas strfroml passes a floating-point
number with long double precision. The following line informs printf_fp
which type of floating-point number is being passed. */
info.is_long_double = __builtin_types_compatible_p (FLOAT, long double);
/* Similarly, the function strfromf128 passes a floating-point number in
_Float128 format to printf_fp. */
#if __HAVE_DISTINCT_FLOAT128
info.is_binary128 = __builtin_types_compatible_p (FLOAT, _Float128);
#endif
/* Set info according to the format string. */
info.prec = precision;
info.spec = specifier;
if (info.spec != 'a' && info.spec != 'A')
done = __printf_fp_l (&sfile.f._sbf._f, _NL_CURRENT_LOCALE, &info, &fpptr);
else
done = __printf_fphex (&sfile.f._sbf._f, &info, &fpptr);
/* Terminate the string. */
if (sfile.f._sbf._f._IO_buf_base != sfile.overflow_buf)
*sfile.f._sbf._f._IO_write_ptr = '\0';
return done;
}