5.2 KiB
libkernaux
Auxiliary library for kernel development.
Table of contents
API
- Measurement units utils (work in progress)
- Simple command line parser
- Multiboot 2 (GRUB 2) information parser
- Serial console
- Page Frame Allocator (work in progress)
- ELF utils (work in progress)
- Architecture-specific helpers
- printf replacement (work in progress)
- stdlib replacement:
memsetstrlenstrncpyitoa(work in progress)
Tips
Compilation
./autogen.sh
./configure
make
sudo make install
You can test with make check.
This is just a usual library. You can use most of it's APIs in hosted environment.
Cross-compilation
Create configuration script with ./autogen.sh.
Configure with cross-compiler in
$PATH to make without it in $PATH:
./configure \
--host='i386-elftailix' \
AR="$(which i386-elftailix-ar)" \
CC="$(which i386-elftailix-gcc)" \
RANLIB="$(which i386-elftailix-ranlib)" \
CFLAGS='-ffreestanding -nostdlib -fno-builtin -fno-stack-protector'
You can see the following messages. It's a bug 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.
When configured with cross-compiler, library can't be build and installed with
just make && sudo make install. Instead use the following commands:
make libkernaux.asudo make install-execsudo make install-data
Check if compilation targets i386: objdump -d src/arch/i386.o. It should
output something like this:
src/arch/i386.o: file format elf32-i386
Disassembly of section .text:
00000000 <kernaux_arch_i386_hang>:
0: fa cli
1: f4 hlt
2: eb fc jmp 0 <kernaux_arch_i386_hang>
00000004 <kernaux_arch_i386_read_cr0>:
4: 0f 20 c0 mov %cr0,%eax
7: c3 ret
00000008 <kernaux_arch_i386_read_cr4>:
8: 0f 20 e0 mov %cr4,%eax
b: c3 ret
0000000c <kernaux_arch_i386_write_cr0>:
c: 8b 44 24 04 mov 0x4(%esp),%eax
10: 0f 22 c0 mov %eax,%cr0
13: c3 ret
00000014 <kernaux_arch_i386_write_cr3>:
14: 8b 44 24 04 mov 0x4(%esp),%eax
18: 0f 22 d8 mov %eax,%cr3
1b: c3 ret
0000001c <kernaux_arch_i386_write_cr4>:
1c: 8b 44 24 04 mov 0x4(%esp),%eax
20: 0f 22 e0 mov %eax,%cr4
23: c3 ret
Portability
Except GNU/Linux, the library is periodically successfully built (starting with
./autogen.sh) and tested with autoconf, automake, binutils and
gcc/clang (depending on what is present) on the following operating
systems:
- FreeBSD 13.0
- Minix 3.3.0
- NetBSD 9.2
- OpenBSD 7.0