reactos/sdk/lib/ucrt/misc/perror.cpp
2025-01-16 14:18:53 +02:00

72 lines
2.1 KiB
C++

/***
*perror.c - print system error message
*
* Copyright (c) Microsoft Corporation. All rights reserved.
*
*Purpose:
* defines perror() - print system error message
* System error message are indexed by errno; conforms to XENIX
* standard, with much compatability with 1983 uniforum draft standard.
*
*******************************************************************************/
#include <corecrt_internal.h>
#include <corecrt_internal_lowio.h>
#include <corecrt_internal_ptd_propagation.h>
#include <io.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#pragma warning(disable:__WARNING_RETVAL_IGNORED_FUNC_COULD_FAIL) // 6031 return value ignored
/***
*void perror(message) - print system error message
*
*Purpose:
* prints user's error message, then follows it with ": ", then the system
* error message, then a newline. All output goes to stderr. If user's
* message is nullptr or a null string, only the system error message is
* printer. If errno is weird, prints "Unknown error".
*
*Entry:
* const char *message - users message to prefix system error message
*
*Exit:
* Prints message; no return value.
*
*Exceptions:
*
*******************************************************************************/
static void __cdecl _perror_internal(char const* const user_prefix, __crt_cached_ptd_host& ptd)
{
int const fh = 2;
__acrt_lowio_lock_fh(fh);
__try
{
if (user_prefix != nullptr && user_prefix[0] != '\0')
{
_write_nolock(fh, user_prefix, static_cast<unsigned>(strlen(user_prefix)), ptd);
_write_nolock(fh, ": ", 2, ptd);
}
// Use PTD directly to access previously set errno value.
char const* const system_message = _get_sys_err_msg(ptd.get_raw_ptd()->_terrno);
_write_nolock(fh, system_message, static_cast<unsigned>(strlen(system_message)), ptd);
_write_nolock(fh, "\n", 1, ptd);
}
__finally
{
__acrt_lowio_unlock_fh( fh );
}
__endtry
}
extern "C" void __cdecl perror(char const* const user_prefix)
{
__crt_cached_ptd_host ptd;
return _perror_internal(user_prefix, ptd);
}