mirror of
https://gitlab.isc.org/isc-projects/bind9
synced 2025-08-24 02:58:38 +00:00
This commit converts the license handling to adhere to the REUSE specification. It specifically: 1. Adds used licnses to LICENSES/ directory 2. Add "isc" template for adding the copyright boilerplate 3. Changes all source files to include copyright and SPDX license header, this includes all the C sources, documentation, zone files, configuration files. There are notes in the doc/dev/copyrights file on how to add correct headers to the new files. 4. Handle the rest that can't be modified via .reuse/dep5 file. The binary (or otherwise unmodifiable) files could have license places next to them in <foo>.license file, but this would lead to cluttered repository and most of the files handled in the .reuse/dep5 file are system test files.
57 lines
2.2 KiB
Plaintext
57 lines
2.2 KiB
Plaintext
<!--
|
|
Copyright (C) Internet Systems Consortium, Inc. ("ISC")
|
|
|
|
SPDX-License-Identifier: MPL-2.0
|
|
|
|
This Source Code Form is subject to the terms of the Mozilla Public
|
|
License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
file, you can obtain one at https://mozilla.org/MPL/2.0/.
|
|
|
|
See the COPYRIGHT file distributed with this work for additional
|
|
information regarding copyright ownership.
|
|
-->
|
|
|
|
Unexpected Errors
|
|
|
|
For portability, the ISC and DNS libraries define their own result codes
|
|
instead of using the operating system's. E.g. the ISC library uses
|
|
ISC_R_NOMEMORY instead of the UNIX-specific ENOMEM.
|
|
|
|
The ISC and DNS libraries have a common way of looking at errors and
|
|
other non-success results. An "expected" result is something that can
|
|
happen in the ordinary course of using a function, that is not very
|
|
improbable, and that the caller might care to know. For example, a
|
|
function which opens a file must have a way to say "file not found"
|
|
and "permission denied".
|
|
|
|
Other kinds of errors are "unexpected". For example, an I/O error
|
|
might occur. When an unexpected error occurs, we want to be able to
|
|
log the information, but we don't want to translate every
|
|
operating-system-specific error code into and ISC_R_ or DNS_R_ code
|
|
because the are too many of them, and they aren't meaningful to
|
|
clients anyway (they're unexpected errors). If we were using a
|
|
language where we could throw an exception, we'd do that. Since we're
|
|
not, we call UNEXPECTED_ERROR(). E.g.
|
|
|
|
#include <isc/error.h>
|
|
|
|
void foo() {
|
|
if (some_unix_thang() < 0) {
|
|
UNEXPECTED_ERROR(__FILE__, __LINE__,
|
|
"some_unix_thang() failed: %s",
|
|
strerror(errno));
|
|
return (ISC_R_UNEXPECTED);
|
|
}
|
|
}
|
|
|
|
The UNEXPECTED error routine may be specified by the calling application. It
|
|
will log the error somehow (e.g. via. syslog, or printing to stderr).
|
|
|
|
This method is a compromise. It makes useful error information available,
|
|
but avoids the complexity of a more sophisticated multi-library "error table"
|
|
scheme.
|
|
|
|
In the (rare) situation where a library routine encounters a fatal error and
|
|
has no way of reporting the error to the application, the library may call
|
|
FATAL_ERROR(). This will log the problem and then terminate the application.
|