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 may only change when major version number is increased (or minor while major is zero). Work-in-progress APIs can change at any time. * Basic features * [Feature macros](/include/kernaux/version.h.in) (*work in progress*) * [Runtime environment](/include/kernaux/runtime.h) (*non-breaking since* **0.7.0**) * [Macros](/include/kernaux/macro.h) (*non-breaking since* **0.6.0**) * [Example: packing](/examples/macro_packing.c) * [Example: BITS](/examples/macro_bits.c) * [Example: CAST\_\*](/examples/macro_cast.c); * [Example: CONTAINER\_OF](/examples/macro_container_of.c) * [Example: STATIC\_TEST\*](/examples/macro_static_test.c) * Stack trace *(planned)* * Generic types * [Display](/include/kernaux/generic/display.h) (*non-breaking since* **0.7.0**) * [Example](/examples/generic_display.c) * [Memory allocator](/include/kernaux/generic/malloc.h) (*non-breaking since* **0.5.0**) * [Example](/examples/generic_malloc.c) * [Mutex](/include/kernaux/generic/mutex.h) (*non-breaking since* **0.5.0**) * [Example](/examples/generic_mutex.c) * Algorithms * [Free list memory allocator](/include/kernaux/free_list.h) (*non-breaking since* **0.5.0**) * [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*) * [MBR](/include/kernaux/mbr.h) (*work in progress*) * [Multiboot 2 (GRUB 2)](/include/kernaux/multiboot2.h.in) (*non-breaking since* **0.7.0**) * [Example: header macros](/examples/multiboot2_header_macro.c) * Utilities * [Measurement units utils](/include/kernaux/units.h) (*work in progress*) * [Example: To human](/examples/units_human.c) * [Memory map](/include/kernaux/memmap.h) (*non-breaking since* **0.7.0**) * [Example](/examples/memmap.c) * [printf format parser](/include/kernaux/printf_fmt.h) (*non-breaking since* **0.6.0**) * [Example](/examples/printf_fmt.c) * Usual functions * [itoa/ftoa replacement](/include/kernaux/ntoa.h) (*non-breaking since* **0.4.0**) * [Example](/examples/ntoa.c) * [printf replacement](/include/kernaux/printf.h) (*non-breaking since* **0.5.0**) * [Example: fprintf](/examples/printf_file.c) * [Example: vfprintf](/examples/printf_file_va.c) * [Example: snprintf](/examples/printf_str.c) * [Example: vsnprintf](/examples/printf_str_va.c) * Architecture-specific code (*work in progress*) * [Declarations](/include/kernaux/arch/) * [Functions](/include/kernaux/asm/) ### Definitions `#define` the following C preprocessor macros before including `` and `` files. They have effect on your code, not the library code. * `KERNAUX_ACCESS_PRIVATE` - disable access modifier "private". Don't do this! * `KERNAUX_ACCESS_PROTECTED` - disable access modifier "protected". Only do this in a file where you implement an inherited type. * `KERNAUX_BITFIELDS` - enable bitfields in packed structs. It doesn't follow the C standard and may be incompatible with some compilers. ### 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 assertions are 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-checks` - enable usual tests and examples * `--enable-checks-all` - enable all checks * `--enable-checks-cppcheck` - enable cppcheck * `--enable-checks-pthreads` - enable tests that require pthreads * `--enable-checks-python` - enable tests that require Python 3 with YAML and Jinja2 * `--enable-fixtures` - enable fixtures for tests and bindings * `--enable-pkg-config[=PATH]` - install pkg-config files [PATH='${libdir}/pkgconfig'] ### Default options #### Features * `--(enable|disable)-assert` - assertions * `--(enable|disable)-float` - floating-point arithmetic * `--(enable|disable)-werror` - fail on warning (`CFLAGS+='-Werror'`) #### Packages All packages are included by default. To exclude all packages except those explicitly included, use `--without-all`. * `--with[out]-arch-all` - all architectures * `--with[out]-arch-i386` - architecture i386 * `--with[out]-arch-riscv64` - architecture riscv64 * `--with[out]-arch-x86-64` - architecture x86-64 * `--with[out]-asm` - kernel assembler helpers * `--with[out]-cmdline` - command line parser * `--with[out]-free-list` - free list memory allocator * `--with[out]-memmap` - memory map * `--with[out]-multiboot2` - Multiboot 2 utils * `--with[out]-ntoa` - itoa/ftoa * `--with[out]-printf` - printf Tips ---- ### Installation ``` ./autogen.sh # if present ./configure make sudo make install sudo ldconfig # on GNU/Linux ``` This is just a usual library. You can use most of it's APIs in hosted environment. ### Development ``` ./autogen.sh # if present ./configure --enable-fixtures --enable-checks # or --enable-checks-all, but see prerequisites make ``` You can test with `make check`. #### See also * [GitHub Actions](/.github/) for **GNU/Linux** build environment * [Cirrus CI](/.cirrus.yml) for **FreeBSD** build environment * [sourcehut CI](/.openbsd.yml) for **OpenBSD** build environment ### Cross Create configuration script with `./autogen.sh` (if present). The library requires some functions from the standard C library. Use [libclayer](https://github.com/tailix/libclayer). Let's assume that your target triplet is `i386-elf`. Configure with [cross-compiler](https://wiki.osdev.org/GCC_Cross-Compiler) in `$PATH` to make without it in `$PATH`: ``` ./configure \ --host='i386-elf' \ --disable-shared \ --enable-freestanding \ CC="$(which i386-elf-gcc)" \ CFLAGS='-I' ``` The variables include `AR`, `AS`, `CC`, `CCAS`, `LD`, `NM`, `OBJDUMP`, `RANLIB`, `STRIP`. See the generated `config.log` for more information. 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 ```