___      _    _ _
                            / __|__ _| |__(_) |_ ___
                           | (__/ _` | / _| |  _/ -_)
                            \___\__,_|_\__|_|\__\___|

Calcite is a hobby operating system. I am maintaining a weblog with occasional
status updates at <https://www.benjidial.net/weblog/calcite>.

Calcite is very much alpha software. Do not expect it to do anything useful.

                                === Building ===

Calcite requires some software to be installed before it can be built:
* a C compiler supporting C99 (e.g. GCC)
* a C++ compiler supporting C++17 (e.g. GCC)
* curl
* GNU ld
* GNU tar
* GNU xorriso
* NASM
* Ninja build system

On Debian, it is sufficient to run this command:
  apt install binutils curl g++ gcc nasm ninja-build tar xorriso

The Calcite disk includes some software that is not in this repository.
To download that software into the repository tree, use the get-dependencies.sh
script. To remove those files, use the clean-dependencies.sh script.

Next, use the make-build.sh script to make the ninja.build file. Running this
script with no arguments will display information about the arguments that this
script accepts.

Finally, just run ninja to build the disk. A disk image will be placed at
build/disk.iso. This disk must be booted with UEFI. All build files, including
ninja.build, but not including the files downloaded by get-dependencies.sh,
can be removed with the clean-build.sh script.

                                === Debugging ===

More software must be installed to debug Calcite:
* GNU's GDB
* QEMU, including the x86_64 system

On Debian, it is sufficient to run this command:
  apt install gdb qemu-system-x86

Run "gdb -x qemu.gdb" to boot Calcite in QEMU and attach GDB to it.
The debugging experience will be nicer if debugging symbols were
enabled during the make-build.sh step.

                                 === License ===

Calcite is Copyright 2026 Benji Dial.

Calcite 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 (version 3 only).

Calcite 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
Calcite (in license.txt). If not, see <https://www.gnu.org/licenses/>.

The Calcite disk image includes the Limine bootloader, version 12.5.2. Limine is
Copyright 2019-2026 Mintsuki and contributors, and is used under the terms of
the BSD 2-Clause License, reproduced below:

  Copyright (C) 2019-2026 Mintsuki and contributors.

  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions are met:

  1. Redistributions of source code must n the above copyright notice, this
     list of conditions and the following disclaimer.

  2. 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 HOLDER 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.

Limine has some transitive dependencies. Information about these can be found at
<https://github.com/Limine-Bootloader/Limine/blob/v12.5.2/3RDPARTY.md>.