?? vasnprintf.c
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/* vsprintf with automatic memory allocation.
Copyright (C) 1999, 2002-2005 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify it
under the terms of the GNU Library General Public License as published
by the Free Software Foundation; either version 2, or (at your option)
any later version.
This program 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
USA. */
/* Tell glibc's <stdio.h> to provide a prototype for snprintf().
This must come before <config.h> because <config.h> may include
<features.h>, and once <features.h> has been included, it's too late. */
#ifndef _GNU_SOURCE
# define _GNU_SOURCE 1
#endif
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#ifndef IN_LIBINTL
# include <alloca.h>
#endif
/* Specification. */
#if WIDE_CHAR_VERSION
# include "vasnwprintf.h"
#else
# include "vasnprintf.h"
#endif
#include <stdio.h> /* snprintf(), sprintf() */
#include <stdlib.h> /* abort(), malloc(), realloc(), free() */
#include <string.h> /* memcpy(), strlen() */
#include <errno.h> /* errno */
#include <limits.h> /* CHAR_BIT, INT_MAX */
#include <float.h> /* DBL_MAX_EXP, LDBL_MAX_EXP */
#if WIDE_CHAR_VERSION
# include "wprintf-parse.h"
#else
# include "printf-parse.h"
#endif
/* Checked size_t computations. */
#include "xsize.h"
/* Some systems, like OSF/1 4.0 and Woe32, don't have EOVERFLOW. */
#ifndef EOVERFLOW
# define EOVERFLOW E2BIG
#endif
#ifdef HAVE_WCHAR_T
# ifdef HAVE_WCSLEN
# define local_wcslen wcslen
# else
/* Solaris 2.5.1 has wcslen() in a separate library libw.so. To avoid
a dependency towards this library, here is a local substitute.
Define this substitute only once, even if this file is included
twice in the same compilation unit. */
# ifndef local_wcslen_defined
# define local_wcslen_defined 1
static size_t
local_wcslen (const wchar_t *s)
{
const wchar_t *ptr;
for (ptr = s; *ptr != (wchar_t) 0; ptr++)
;
return ptr - s;
}
# endif
# endif
#endif
#if WIDE_CHAR_VERSION
# define VASNPRINTF vasnwprintf
# define CHAR_T wchar_t
# define DIRECTIVE wchar_t_directive
# define DIRECTIVES wchar_t_directives
# define PRINTF_PARSE wprintf_parse
# define USE_SNPRINTF 1
# if HAVE_DECL__SNWPRINTF
/* On Windows, the function swprintf() has a different signature than
on Unix; we use the _snwprintf() function instead. */
# define SNPRINTF _snwprintf
# else
/* Unix. */
# define SNPRINTF swprintf
# endif
#else
# define VASNPRINTF vasnprintf
# define CHAR_T char
# define DIRECTIVE char_directive
# define DIRECTIVES char_directives
# define PRINTF_PARSE printf_parse
# define USE_SNPRINTF (HAVE_DECL__SNPRINTF || HAVE_SNPRINTF)
# if HAVE_DECL__SNPRINTF
/* Windows. */
# define SNPRINTF _snprintf
# else
/* Unix. */
# define SNPRINTF snprintf
# endif
#endif
CHAR_T *
VASNPRINTF (CHAR_T *resultbuf, size_t *lengthp, const CHAR_T *format, va_list args)
{
DIRECTIVES d;
arguments a;
if (PRINTF_PARSE (format, &d, &a) < 0)
{
errno = EINVAL;
return NULL;
}
#define CLEANUP() \
free (d.dir); \
if (a.arg) \
free (a.arg);
if (printf_fetchargs (args, &a) < 0)
{
CLEANUP ();
errno = EINVAL;
return NULL;
}
{
size_t buf_neededlength;
CHAR_T *buf;
CHAR_T *buf_malloced;
const CHAR_T *cp;
size_t i;
DIRECTIVE *dp;
/* Output string accumulator. */
CHAR_T *result;
size_t allocated;
size_t length;
/* Allocate a small buffer that will hold a directive passed to
sprintf or snprintf. */
buf_neededlength =
xsum4 (7, d.max_width_length, d.max_precision_length, 6);
#if HAVE_ALLOCA
if (buf_neededlength < 4000 / sizeof (CHAR_T))
{
buf = (CHAR_T *) alloca (buf_neededlength * sizeof (CHAR_T));
buf_malloced = NULL;
}
else
#endif
{
size_t buf_memsize = xtimes (buf_neededlength, sizeof (CHAR_T));
if (size_overflow_p (buf_memsize))
goto out_of_memory_1;
buf = (CHAR_T *) malloc (buf_memsize);
if (buf == NULL)
goto out_of_memory_1;
buf_malloced = buf;
}
if (resultbuf != NULL)
{
result = resultbuf;
allocated = *lengthp;
}
else
{
result = NULL;
allocated = 0;
}
length = 0;
/* Invariants:
result is either == resultbuf or == NULL or malloc-allocated.
If length > 0, then result != NULL. */
/* Ensures that allocated >= needed. Aborts through a jump to
out_of_memory if needed is SIZE_MAX or otherwise too big. */
#define ENSURE_ALLOCATION(needed) \
if ((needed) > allocated) \
{ \
size_t memory_size; \
CHAR_T *memory; \
\
allocated = (allocated > 0 ? xtimes (allocated, 2) : 12); \
if ((needed) > allocated) \
allocated = (needed); \
memory_size = xtimes (allocated, sizeof (CHAR_T)); \
if (size_overflow_p (memory_size)) \
goto out_of_memory; \
if (result == resultbuf || result == NULL) \
memory = (CHAR_T *) malloc (memory_size); \
else \
memory = (CHAR_T *) realloc (result, memory_size); \
if (memory == NULL) \
goto out_of_memory; \
if (result == resultbuf && length > 0) \
memcpy (memory, result, length * sizeof (CHAR_T)); \
result = memory; \
}
for (cp = format, i = 0, dp = &d.dir[0]; ; cp = dp->dir_end, i++, dp++)
{
if (cp != dp->dir_start)
{
size_t n = dp->dir_start - cp;
size_t augmented_length = xsum (length, n);
ENSURE_ALLOCATION (augmented_length);
memcpy (result + length, cp, n * sizeof (CHAR_T));
length = augmented_length;
}
if (i == d.count)
break;
/* Execute a single directive. */
if (dp->conversion == '%')
{
size_t augmented_length;
if (!(dp->arg_index == ARG_NONE))
abort ();
augmented_length = xsum (length, 1);
ENSURE_ALLOCATION (augmented_length);
result[length] = '%';
length = augmented_length;
}
else
{
if (!(dp->arg_index != ARG_NONE))
abort ();
if (dp->conversion == 'n')
{
switch (a.arg[dp->arg_index].type)
{
case TYPE_COUNT_SCHAR_POINTER:
*a.arg[dp->arg_index].a.a_count_schar_pointer = length;
break;
case TYPE_COUNT_SHORT_POINTER:
*a.arg[dp->arg_index].a.a_count_short_pointer = length;
break;
case TYPE_COUNT_INT_POINTER:
*a.arg[dp->arg_index].a.a_count_int_pointer = length;
break;
case TYPE_COUNT_LONGINT_POINTER:
*a.arg[dp->arg_index].a.a_count_longint_pointer = length;
break;
#ifdef HAVE_LONG_LONG
case TYPE_COUNT_LONGLONGINT_POINTER:
*a.arg[dp->arg_index].a.a_count_longlongint_pointer = length;
break;
#endif
default:
abort ();
}
}
else
{
arg_type type = a.arg[dp->arg_index].type;
CHAR_T *p;
unsigned int prefix_count;
int prefixes[2];
#if !USE_SNPRINTF
size_t tmp_length;
CHAR_T tmpbuf[700];
CHAR_T *tmp;
/* Allocate a temporary buffer of sufficient size for calling
sprintf. */
{
size_t width;
size_t precision;
width = 0;
if (dp->width_start != dp->width_end)
{
if (dp->width_arg_index != ARG_NONE)
{
int arg;
if (!(a.arg[dp->width_arg_index].type == TYPE_INT))
abort ();
arg = a.arg[dp->width_arg_index].a.a_int;
width = (arg < 0 ? (unsigned int) (-arg) : arg);
}
else
{
const CHAR_T *digitp = dp->width_start;
do
width = xsum (xtimes (width, 10), *digitp++ - '0');
while (digitp != dp->width_end);
}
}
precision = 6;
if (dp->precision_start != dp->precision_end)
{
if (dp->precision_arg_index != ARG_NONE)
{
int arg;
if (!(a.arg[dp->precision_arg_index].type == TYPE_INT))
abort ();
arg = a.arg[dp->precision_arg_index].a.a_int;
precision = (arg < 0 ? 0 : arg);
}
else
{
const CHAR_T *digitp = dp->precision_start + 1;
precision = 0;
while (digitp != dp->precision_end)
precision = xsum (xtimes (precision, 10), *digitp++ - '0');
}
}
switch (dp->conversion)
{
case 'd': case 'i': case 'u':
# ifdef HAVE_LONG_LONG
if (type == TYPE_LONGLONGINT || type == TYPE_ULONGLONGINT)
tmp_length =
(unsigned int) (sizeof (unsigned long long) * CHAR_BIT
* 0.30103 /* binary -> decimal */
* 2 /* estimate for FLAG_GROUP */
)
+ 1 /* turn floor into ceil */
+ 1; /* account for leading sign */
else
# endif
if (type == TYPE_LONGINT || type == TYPE_ULONGINT)
tmp_length =
(unsigned int) (sizeof (unsigned long) * CHAR_BIT
* 0.30103 /* binary -> decimal */
* 2 /* estimate for FLAG_GROUP */
)
+ 1 /* turn floor into ceil */
+ 1; /* account for leading sign */
else
tmp_length =
(unsigned int) (sizeof (unsigned int) * CHAR_BIT
* 0.30103 /* binary -> decimal */
* 2 /* estimate for FLAG_GROUP */
)
+ 1 /* turn floor into ceil */
+ 1; /* account for leading sign */
break;
case 'o':
# ifdef HAVE_LONG_LONG
if (type == TYPE_LONGLONGINT || type == TYPE_ULONGLONGINT)
tmp_length =
(unsigned int) (sizeof (unsigned long long) * CHAR_BIT
* 0.333334 /* binary -> octal */
)
+ 1 /* turn floor into ceil */
+ 1; /* account for leading sign */
else
# endif
if (type == TYPE_LONGINT || type == TYPE_ULONGINT)
tmp_length =
(unsigned int) (sizeof (unsigned long) * CHAR_BIT
* 0.333334 /* binary -> octal */
)
+ 1 /* turn floor into ceil */
+ 1; /* account for leading sign */
else
tmp_length =
(unsigned int) (sizeof (unsigned int) * CHAR_BIT
* 0.333334 /* binary -> octal */
)
+ 1 /* turn floor into ceil */
+ 1; /* account for leading sign */
break;
case 'x': case 'X':
# ifdef HAVE_LONG_LONG
if (type == TYPE_LONGLONGINT || type == TYPE_ULONGLONGINT)
tmp_length =
(unsigned int) (sizeof (unsigned long long) * CHAR_BIT
* 0.25 /* binary -> hexadecimal */
)
+ 1 /* turn floor into ceil */
+ 2; /* account for leading sign or alternate form */
else
# endif
if (type == TYPE_LONGINT || type == TYPE_ULONGINT)
tmp_length =
(unsigned int) (sizeof (unsigned long) * CHAR_BIT
* 0.25 /* binary -> hexadecimal */
)
+ 1 /* turn floor into ceil */
+ 2; /* account for leading sign or alternate form */
else
tmp_length =
(unsigned int) (sizeof (unsigned int) * CHAR_BIT
* 0.25 /* binary -> hexadecimal */
)
+ 1 /* turn floor into ceil */
+ 2; /* account for leading sign or alternate form */
break;
case 'f': case 'F':
# ifdef HAVE_LONG_DOUBLE
if (type == TYPE_LONGDOUBLE)
tmp_length =
(unsigned int) (LDBL_MAX_EXP
* 0.30103 /* binary -> decimal */
* 2 /* estimate for FLAG_GROUP */
)
+ 1 /* turn floor into ceil */
+ 10; /* sign, decimal point etc. */
else
# endif
tmp_length =
(unsigned int) (DBL_MAX_EXP
* 0.30103 /* binary -> decimal */
* 2 /* estimate for FLAG_GROUP */
)
+ 1 /* turn floor into ceil */
+ 10; /* sign, decimal point etc. */
tmp_length = xsum (tmp_length, precision);
break;
case 'e': case 'E': case 'g': case 'G':
case 'a': case 'A':
tmp_length =
12; /* sign, decimal point, exponent etc. */
tmp_length = xsum (tmp_length, precision);
break;
case 'c':
# if defined HAVE_WINT_T && !WIDE_CHAR_VERSION
if (type == TYPE_WIDE_CHAR)
tmp_length = MB_CUR_MAX;
else
# endif
tmp_length = 1;
break;
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