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// Debugging support -*- C++ -*-
// Copyright (C) 2013-2022 Free Software Foundation, Inc.
//
// This file is part of GCC.
//
// GCC 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 3, or (at your option)
// any later version.
//
// GCC 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.
//
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
#include <stdarg.h>
#include <stddef.h>
#include <bits/functexcept.h>
namespace __gnu_cxx {
// Private helper to throw logic error if snprintf_lite runs out
// of space (which is not expected to ever happen).
// NUL-terminates __buf.
void
__throw_insufficient_space(const char *__buf, const char *__bufend)
__attribute__((__noreturn__));
void
__throw_insufficient_space(const char *__buf, const char *__bufend)
{
// Include space for trailing NUL.
const size_t __len = __bufend - __buf + 1;
const char __err[] = "not enough space for format expansion "
"(Please submit full bug report at https://gcc.gnu.org/bugs/):\n ";
const size_t __errlen = sizeof(__err) - 1;
char *const __e
= static_cast<char*>(__builtin_alloca(__errlen + __len));
__builtin_memcpy(__e, __err, __errlen);
__builtin_memcpy(__e + __errlen, __buf, __len - 1);
__e[__errlen + __len - 1] = '\0';
std::__throw_logic_error(__e);
}
// Private routine to append decimal representation of VAL to the given
// BUFFER, but not more than BUFSIZE characters.
// Does not NUL-terminate the output buffer.
// Returns number of characters appended, or -1 if BUFSIZE is too small.
int __concat_size_t(char *__buf, size_t __bufsize, size_t __val)
{
// Long enough for decimal representation.
int __ilen = 3 * sizeof(__val);
char *__cs = static_cast<char*>(__builtin_alloca(__ilen));
char* __out = __cs + __ilen;
do
{
*--__out = "0123456789"[__val % 10];
__val /= 10;
}
while (__val != 0);
size_t __len = __cs + __ilen - __out;
if (__bufsize < __len)
return -1;
__builtin_memcpy(__buf, __cs + __ilen - __len, __len);
return __len;
}
// Private routine to print into __buf arguments according to format,
// not to exceed __bufsize.
// Only '%%', '%s' and '%zu' format specifiers are understood.
// Returns number of characters printed (excluding terminating NUL).
// Always NUL-terminates __buf.
// Throws logic_error on insufficient space.
int __snprintf_lite(char *__buf, size_t __bufsize, const char *__fmt,
va_list __ap)
{
char *__d = __buf;
const char *__s = __fmt;
const char *const __limit = __d + __bufsize - 1; // Leave space for NUL.
while (__s[0] != '\0' && __d < __limit)
{
if (__s[0] == '%')
switch (__s[1])
{
default: // Stray '%'. Just print it.
break;
case '%': // '%%'
__s += 1;
break;
case 's': // '%s'.
{
const char *__v = va_arg(__ap, const char *);
while (__v[0] != '\0' && __d < __limit)
*__d++ = *__v++;
if (__v[0] != '\0')
// Not enough space for __fmt expansion.
__throw_insufficient_space(__buf, __d);
__s += 2; // Step over %s.
continue;
}
break;
case 'z':
if (__s[2] == 'u') // '%zu' -- expand next size_t arg.
{
const int __len = __concat_size_t(__d, __limit - __d,
va_arg(__ap, size_t));
if (__len > 0)
__d += __len;
else
// Not enough space for __fmt expansion.
__throw_insufficient_space(__buf, __d);
__s += 3; // Step over %zu
continue;
}
// Stray '%zX'. Just print it.
break;
}
*__d++ = *__s++;
}
if (__s[0] != '\0')
// Not enough space for __fmt expansion.
__throw_insufficient_space(__buf, __d);
*__d = '\0';
return __d - __buf;
}
} // __gnu_cxx