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mirror of git://git.gnupg.org/gnupg.git synced 2024-12-23 10:29:58 +01:00
gnupg/gl/vasnprintf.c
2005-06-01 15:48:03 +00:00

902 lines
22 KiB
C

/* 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 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 General Public License for more details.
You should have received a copy of the GNU 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;
case 's':
# ifdef HAVE_WCHAR_T
if (type == TYPE_WIDE_STRING)
{
tmp_length =
local_wcslen (a.arg[dp->arg_index].a.a_wide_string);
# if !WIDE_CHAR_VERSION
tmp_length = xtimes (tmp_length, MB_CUR_MAX);
# endif
}
else
# endif
tmp_length = strlen (a.arg[dp->arg_index].a.a_string);
break;
case 'p':
tmp_length =
(unsigned int) (sizeof (void *) * CHAR_BIT
* 0.25 /* binary -> hexadecimal */
)
+ 1 /* turn floor into ceil */
+ 2; /* account for leading 0x */
break;
default:
abort ();
}
if (tmp_length < width)
tmp_length = width;
tmp_length = xsum (tmp_length, 1); /* account for trailing NUL */
}
if (tmp_length <= sizeof (tmpbuf) / sizeof (CHAR_T))
tmp = tmpbuf;
else
{
size_t tmp_memsize = xtimes (tmp_length, sizeof (CHAR_T));
if (size_overflow_p (tmp_memsize))
/* Overflow, would lead to out of memory. */
goto out_of_memory;
tmp = (CHAR_T *) malloc (tmp_memsize);
if (tmp == NULL)
/* Out of memory. */
goto out_of_memory;
}
#endif
/* Construct the format string for calling snprintf or
sprintf. */
p = buf;
*p++ = '%';
if (dp->flags & FLAG_GROUP)
*p++ = '\'';
if (dp->flags & FLAG_LEFT)
*p++ = '-';
if (dp->flags & FLAG_SHOWSIGN)
*p++ = '+';
if (dp->flags & FLAG_SPACE)
*p++ = ' ';
if (dp->flags & FLAG_ALT)
*p++ = '#';
if (dp->flags & FLAG_ZERO)
*p++ = '0';
if (dp->width_start != dp->width_end)
{
size_t n = dp->width_end - dp->width_start;
memcpy (p, dp->width_start, n * sizeof (CHAR_T));
p += n;
}
if (dp->precision_start != dp->precision_end)
{
size_t n = dp->precision_end - dp->precision_start;
memcpy (p, dp->precision_start, n * sizeof (CHAR_T));
p += n;
}
switch (type)
{
#ifdef HAVE_LONG_LONG
case TYPE_LONGLONGINT:
case TYPE_ULONGLONGINT:
*p++ = 'l';
/*FALLTHROUGH*/
#endif
case TYPE_LONGINT:
case TYPE_ULONGINT:
#ifdef HAVE_WINT_T
case TYPE_WIDE_CHAR:
#endif
#ifdef HAVE_WCHAR_T
case TYPE_WIDE_STRING:
#endif
*p++ = 'l';
break;
#ifdef HAVE_LONG_DOUBLE
case TYPE_LONGDOUBLE:
*p++ = 'L';
break;
#endif
default:
break;
}
*p = dp->conversion;
#if USE_SNPRINTF
p[1] = '%';
p[2] = 'n';
p[3] = '\0';
#else
p[1] = '\0';
#endif
/* Construct the arguments for calling snprintf or sprintf. */
prefix_count = 0;
if (dp->width_arg_index != ARG_NONE)
{
if (!(a.arg[dp->width_arg_index].type == TYPE_INT))
abort ();
prefixes[prefix_count++] = a.arg[dp->width_arg_index].a.a_int;
}
if (dp->precision_arg_index != ARG_NONE)
{
if (!(a.arg[dp->precision_arg_index].type == TYPE_INT))
abort ();
prefixes[prefix_count++] = a.arg[dp->precision_arg_index].a.a_int;
}
#if USE_SNPRINTF
/* Prepare checking whether snprintf returns the count
via %n. */
ENSURE_ALLOCATION (xsum (length, 1));
result[length] = '\0';
#endif
for (;;)
{
size_t maxlen;
int count;
int retcount;
maxlen = allocated - length;
count = -1;
retcount = 0;
#if USE_SNPRINTF
# define SNPRINTF_BUF(arg) \
switch (prefix_count) \
{ \
case 0: \
retcount = SNPRINTF (result + length, maxlen, buf, \
arg, &count); \
break; \
case 1: \
retcount = SNPRINTF (result + length, maxlen, buf, \
prefixes[0], arg, &count); \
break; \
case 2: \
retcount = SNPRINTF (result + length, maxlen, buf, \
prefixes[0], prefixes[1], arg, \
&count); \
break; \
default: \
abort (); \
}
#else
# define SNPRINTF_BUF(arg) \
switch (prefix_count) \
{ \
case 0: \
count = sprintf (tmp, buf, arg); \
break; \
case 1: \
count = sprintf (tmp, buf, prefixes[0], arg); \
break; \
case 2: \
count = sprintf (tmp, buf, prefixes[0], prefixes[1],\
arg); \
break; \
default: \
abort (); \
}
#endif
switch (type)
{
case TYPE_SCHAR:
{
int arg = a.arg[dp->arg_index].a.a_schar;
SNPRINTF_BUF (arg);
}
break;
case TYPE_UCHAR:
{
unsigned int arg = a.arg[dp->arg_index].a.a_uchar;
SNPRINTF_BUF (arg);
}
break;
case TYPE_SHORT:
{
int arg = a.arg[dp->arg_index].a.a_short;
SNPRINTF_BUF (arg);
}
break;
case TYPE_USHORT:
{
unsigned int arg = a.arg[dp->arg_index].a.a_ushort;
SNPRINTF_BUF (arg);
}
break;
case TYPE_INT:
{
int arg = a.arg[dp->arg_index].a.a_int;
SNPRINTF_BUF (arg);
}
break;
case TYPE_UINT:
{
unsigned int arg = a.arg[dp->arg_index].a.a_uint;
SNPRINTF_BUF (arg);
}
break;
case TYPE_LONGINT:
{
long int arg = a.arg[dp->arg_index].a.a_longint;
SNPRINTF_BUF (arg);
}
break;
case TYPE_ULONGINT:
{
unsigned long int arg = a.arg[dp->arg_index].a.a_ulongint;
SNPRINTF_BUF (arg);
}
break;
#ifdef HAVE_LONG_LONG
case TYPE_LONGLONGINT:
{
long long int arg = a.arg[dp->arg_index].a.a_longlongint;
SNPRINTF_BUF (arg);
}
break;
case TYPE_ULONGLONGINT:
{
unsigned long long int arg = a.arg[dp->arg_index].a.a_ulonglongint;
SNPRINTF_BUF (arg);
}
break;
#endif
case TYPE_DOUBLE:
{
double arg = a.arg[dp->arg_index].a.a_double;
SNPRINTF_BUF (arg);
}
break;
#ifdef HAVE_LONG_DOUBLE
case TYPE_LONGDOUBLE:
{
long double arg = a.arg[dp->arg_index].a.a_longdouble;
SNPRINTF_BUF (arg);
}
break;
#endif
case TYPE_CHAR:
{
int arg = a.arg[dp->arg_index].a.a_char;
SNPRINTF_BUF (arg);
}
break;
#ifdef HAVE_WINT_T
case TYPE_WIDE_CHAR:
{
wint_t arg = a.arg[dp->arg_index].a.a_wide_char;
SNPRINTF_BUF (arg);
}
break;
#endif
case TYPE_STRING:
{
const char *arg = a.arg[dp->arg_index].a.a_string;
SNPRINTF_BUF (arg);
}
break;
#ifdef HAVE_WCHAR_T
case TYPE_WIDE_STRING:
{
const wchar_t *arg = a.arg[dp->arg_index].a.a_wide_string;
SNPRINTF_BUF (arg);
}
break;
#endif
case TYPE_POINTER:
{
void *arg = a.arg[dp->arg_index].a.a_pointer;
SNPRINTF_BUF (arg);
}
break;
default:
abort ();
}
#if USE_SNPRINTF
/* Portability: Not all implementations of snprintf()
are ISO C 99 compliant. Determine the number of
bytes that snprintf() has produced or would have
produced. */
if (count >= 0)
{
/* Verify that snprintf() has NUL-terminated its
result. */
if (count < maxlen && result[length + count] != '\0')
abort ();
/* Portability hack. */
if (retcount > count)
count = retcount;
}
else
{
/* snprintf() doesn't understand the '%n'
directive. */
if (p[1] != '\0')
{
/* Don't use the '%n' directive; instead, look
at the snprintf() return value. */
p[1] = '\0';
continue;
}
else
{
/* Look at the snprintf() return value. */
if (retcount < 0)
{
/* HP-UX 10.20 snprintf() is doubly deficient:
It doesn't understand the '%n' directive,
*and* it returns -1 (rather than the length
that would have been required) when the
buffer is too small. */
size_t bigger_need =
xsum (xtimes (allocated, 2), 12);
ENSURE_ALLOCATION (bigger_need);
continue;
}
else
count = retcount;
}
}
#endif
/* Attempt to handle failure. */
if (count < 0)
{
if (!(result == resultbuf || result == NULL))
free (result);
if (buf_malloced != NULL)
free (buf_malloced);
CLEANUP ();
errno = EINVAL;
return NULL;
}
#if !USE_SNPRINTF
if (count >= tmp_length)
/* tmp_length was incorrectly calculated - fix the
code above! */
abort ();
#endif
/* Make room for the result. */
if (count >= maxlen)
{
/* Need at least count bytes. But allocate
proportionally, to avoid looping eternally if
snprintf() reports a too small count. */
size_t n =
xmax (xsum (length, count), xtimes (allocated, 2));
ENSURE_ALLOCATION (n);
#if USE_SNPRINTF
continue;
#endif
}
#if USE_SNPRINTF
/* The snprintf() result did fit. */
#else
/* Append the sprintf() result. */
memcpy (result + length, tmp, count * sizeof (CHAR_T));
if (tmp != tmpbuf)
free (tmp);
#endif
length += count;
break;
}
}
}
}
/* Add the final NUL. */
ENSURE_ALLOCATION (xsum (length, 1));
result[length] = '\0';
if (result != resultbuf && length + 1 < allocated)
{
/* Shrink the allocated memory if possible. */
CHAR_T *memory;
memory = (CHAR_T *) realloc (result, (length + 1) * sizeof (CHAR_T));
if (memory != NULL)
result = memory;
}
if (buf_malloced != NULL)
free (buf_malloced);
CLEANUP ();
*lengthp = length;
if (length > INT_MAX)
goto length_overflow;
return result;
length_overflow:
/* We could produce such a big string, but its length doesn't fit into
an 'int'. POSIX says that snprintf() fails with errno = EOVERFLOW in
this case. */
if (result != resultbuf)
free (result);
errno = EOVERFLOW;
return NULL;
out_of_memory:
if (!(result == resultbuf || result == NULL))
free (result);
if (buf_malloced != NULL)
free (buf_malloced);
out_of_memory_1:
CLEANUP ();
errno = ENOMEM;
return NULL;
}
}
#undef SNPRINTF
#undef USE_SNPRINTF
#undef PRINTF_PARSE
#undef DIRECTIVES
#undef DIRECTIVE
#undef CHAR_T
#undef VASNPRINTF