Magisk/native/src/crt0/bionic/strerror.cpp

101 lines
3.5 KiB
C++

/*
* Copyright (C) 2012 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
// -std=gnu++XX automatically defines _GNU_SOURCE, which then means that <string.h>
// gives us the GNU variant, which is not what we're defining here.
#undef _GNU_SOURCE
#include <string.h>
#include <errno.h>
#include <limits.h>
#include "private/ErrnoRestorer.h"
#include <string.h>
#include <stdio.h>
// The arraysize(arr) macro returns the # of elements in an array arr.
// The expression is a compile-time constant, and therefore can be
// used in defining new arrays, for example. If you use arraysize on
// a pointer by mistake, you will get a compile-time error.
//
// One caveat is that arraysize() doesn't accept any array of an
// anonymous type or a type defined inside a function.
//
// This template function declaration is used in defining arraysize.
// Note that the function doesn't need an implementation, as we only
// use its type.
template <typename T, size_t N>
char (&ArraySizeHelper(T (&array)[N]))[N]; // NOLINT(readability/casting)
#define arraysize(array) (sizeof(ArraySizeHelper(array)))
static const char* __sys_error_descriptions[] = {
#define __BIONIC_ERRDEF(error_number, error_description) [error_number] = error_description,
#include "private/bionic_errdefs.h"
};
static inline const char* __strerror_lookup(int error_number) {
if (error_number < 0 || error_number >= static_cast<int>(arraysize(__sys_error_descriptions))) {
return nullptr;
}
return __sys_error_descriptions[error_number];
}
int strerror_r(int error_number, char* buf, size_t buf_len) {
ErrnoRestorer errno_restorer;
size_t length;
const char* error_name = __strerror_lookup(error_number);
if (error_name != nullptr) {
length = strlcpy(buf, error_name, buf_len);
} else {
length = snprintf(buf, buf_len, "Unknown error %d", error_number);
}
if (length >= buf_len) {
return ERANGE;
}
return 0;
}
char* strerror(int error_number) {
static char strerror_buf[NL_TEXTMAX];
// Just return the original constant in the easy cases.
char* result = const_cast<char*>(__strerror_lookup(error_number));
if (result != nullptr) {
return result;
}
result = strerror_buf;
strerror_r(error_number, result, sizeof(strerror_buf));
return result;
}