libkernaux ========== [![Build status](https://github.com/tailix/libkernaux/actions/workflows/main.yml/badge.svg)](https://github.com/tailix/libkernaux/actions/workflows/main.yml) [![Build status (FreeBSD)](https://api.cirrus-ci.com/github/tailix/libkernaux.svg?task=Main%20(FreeBSD))](https://cirrus-ci.com/github/tailix/libkernaux) Auxiliary library for kernel development. [Topic on OSDev.org forum](https://forum.osdev.org/viewtopic.php?f=1&t=37958). Table of contents ----------------- * [Overview](#libkernaux) * [Table of contents](#table-of-contents) * [API](#api) * [Headers](#headers) * [Definitions](#definitions) * [Global variables](#global-variables) * [Configuration](#configuration) * [Non-default options](#non-default-options) * [Default options](#default-options) * [Tips](#tips) * [Installation](#installation) * [Development](#development) * [Cross](#cross) API --- ### Headers We use [semantic versioning](https://semver.org) for stable APIs. Stable APIs can only change when major version number is increased (or minor while major is zero). Work-in-progress APIs can change at any time. * Runtime environment * [Feature macros](/include/kernaux/version.h.in) (*work in progress*) * [Assertions](/include/kernaux/assert.h) (*non-breaking since* **?.?.?**) * [Assert](/examples/assert.c) * [Panic](/examples/panic.c) * Stack trace *(planned)* * [Input/output](/include/kernaux/io.h) (*work in progress*) * Architecture-specific code (*work in progress*) * [Declarations](/include/kernaux/arch/) * [Functions](/include/kernaux/asm/) * Device drivers (for debugging only) * [Serial console](/include/kernaux/console.h) (*work in progress*) * [Framebuffer](/include/kernaux/framebuffer.h) (*planned*) * USB (*planned*) * Algorithms * [Simple command line parser](/include/kernaux/cmdline.h) (*non-breaking since* **0.2.0**) * [Example](/examples/cmdline.c) * [Page Frame Allocator](/include/kernaux/pfa.h) (*work in progress*) * [Example](/examples/pfa.c) * Data formats * [ELF](/include/kernaux/elf.h) (*work in progress*) * [Master Boot Record](/include/kernaux/mbr.h) (*work in progress*) * [Multiboot 2 (GRUB 2)](/include/kernaux/multiboot2.h) (*work in progress*) * Stivale 2 (Limine) (*planned*) * Utilities * [Measurement units utils](/include/kernaux/units.h) (*work in progress*) * [To human](/examples/units_human.c) * [Memory map](/include/kernaux/memmap.h.in) (*non-breaking since* **?.?.?**) * [Example](/examples/memmap.c) * [printf format parser](/include/kernaux/printf_fmt.h) (*work in progress*) * Code from [https://github.com/mpaland/printf](https://github.com/mpaland/printf). Thank you! * [Example](/examples/printf_fmt.c) * Usual functions * [itoa/ftoa replacement](/include/kernaux/ntoa.h) (*non-breaking since* **?.?.?**) * [Example](/examples/ntoa.c) * [printf replacement](/include/kernaux/printf.h.in) (*non-breaking since* **?.?.?**) * Code from [https://github.com/mpaland/printf](https://github.com/mpaland/printf). Thank you! * [fprintf](/examples/fprintf.c) * [vfprintf](/examples/fprintf_va.c) * [snprintf](/examples/snprintf.c) * [vsnprintf](/examples/snprintf_va.c) * libc replacement (*work in progress*) * [ctype.h](/libc/include/ctype.h) * [inttypes.h](/libc/include/inttypes.h) * [setjmo.h](/libc/include/setjmo.h) * [stdlib.h](/libc/include/stdlib.h) * [string.h](/libc/include/string.h) * [sys/types.h](/libc/include/sys/types.h) ### Definitions Define the following C preprocessor macros before including `` and `` files. They have effect on your code, not the library code. * `KERNAUX_DEBUG` - enable assertions ### Global variables ```c // in void (*kernaux_assert_cb)(const char *file, int line, const char *msg) ``` Assertion callback. It's better to always set it to some function which always interrupts the execution, even when debugging is disabled. It may for example call `abort()` in hosted environment, raise an exception in Ruby, panic in Rust or power off the machine in freestanding environment. It may also log the error location and message. Configuration ------------- Because this library has no external dependencies, we use **autoconf** features to control behavior of the library, and packages to choose it's components. Configuration options also follow the [semantic versioning](https://semver.org) scheme and are split into stable and work-in-progress ones. Here we cover only stable options. ### Non-default options #### Features * `--enable-freestanding` - build for freestanding environment * `--enable-split-libc` - split off libc * `--enable-tests` - enable usual tests and examples * `--enable-tests-all` - enable all tests * `--enable-tests-python` - enable tests that require Python 3 with YAML and Jinja2 #### Packages * `--with-libc` - provides the replacement for some standard C functions. Useful in freestanding environment, where no libc is present. ### Default options #### Features * `--(enable|disable)-debug` - debugging * `--(enable|disable)-float` - floating-point arithmetic * `--(enable|disable)-werror` - fail on warning (`CFLAGS+='-Werror'`) #### Packages All packages are included by default. To exclude all packages except those explicitly included, use `--without-all`. * `--with[out]-cmdline` - command line parser * `--with[out]-file` - file simulator * `--with[out]-memmap` - memory map * `--with[out]-ntoa` - itoa/ftoa * `--with[out]-printf` - printf Tips ---- ### Installation ``` ./autogen.sh # if present ./configure make sudo make install ``` This is just a usual library. You can use most of it's APIs in hosted environment. ### Development ``` ./autogen.sh # if present ./configure --enable-tests # or --enable-tests-all, but see prerequisites make ``` You can test with `make check`. ### Cross Create configuration script with `./autogen.sh` (if present). Let's assume that your target triplet is `i386-elf`. Configure with [cross-compiler](https://wiki.osdev.org/GCC_Cross-Compiler) in `$PATH` to make without it in `$PATH`: ``` ./configure \ --host='i386-elf' \ --enable-freestanding \ --with-libc \ AR="$(which i386-elf-ar)" \ CC="$(which i386-elf-gcc)" \ RANLIB="$(which i386-elf-ranlib)" ``` You can see the following messages. It's [a bug](https://savannah.gnu.org/support/index.php?110393) in **autoconf**, just ignore it. ``` checking for _Bool... no checking stdarg.h usability... no checking stdarg.h presence... yes configure: WARNING: stdarg.h: present but cannot be compiled configure: WARNING: stdarg.h: check for missing prerequisite headers? configure: WARNING: stdarg.h: see the Autoconf documentation configure: WARNING: stdarg.h: section "Present But Cannot Be Compiled" configure: WARNING: stdarg.h: proceeding with the compiler's result configure: WARNING: ## ---------------------------------------------------------- ## configure: WARNING: ## Report this to https://github.com/tailix/libkernaux/issues ## configure: WARNING: ## ---------------------------------------------------------- ## checking for stdarg.h... no checking stddef.h usability... no checking stddef.h presence... yes configure: WARNING: stddef.h: present but cannot be compiled configure: WARNING: stddef.h: check for missing prerequisite headers? configure: WARNING: stddef.h: see the Autoconf documentation configure: WARNING: stddef.h: section "Present But Cannot Be Compiled" configure: WARNING: stddef.h: proceeding with the compiler's result configure: WARNING: ## ---------------------------------------------------------- ## configure: WARNING: ## Report this to https://github.com/tailix/libkernaux/issues ## configure: WARNING: ## ---------------------------------------------------------- ## checking for stddef.h... no ``` To install into specific directory use full path: `DESTDIR="$(pwd)/dest" make install` instead of `DESTDIR=dest make install`. Check if compilation targets i386: `objdump -d src/asm/i386.o`. It should output something like this: ``` src/asm/i386.o: file format elf32-i386 Disassembly of section .text: 00000000 : 0: 0f 20 c0 mov %cr0,%eax 3: c3 ret 00000004 : 4: 0f 20 e0 mov %cr4,%eax 7: c3 ret 00000008 : 8: 8b 44 24 04 mov 0x4(%esp),%eax c: 0f 22 c0 mov %eax,%cr0 f: c3 ret 00000010 : 10: 8b 44 24 04 mov 0x4(%esp),%eax 14: 0f 22 d8 mov %eax,%cr3 17: c3 ret 00000018 : 18: 8b 44 24 04 mov 0x4(%esp),%eax 1c: 0f 22 e0 mov %eax,%cr4 1f: c3 ret ```