I've been using other tables but they were always incomplete and often x86_64 only. This one contains everything: number, symbol, links to kernel implementation, signature, user space ABI registers. And I can select kernel version, kernel binary interface and processor architecture!
I'm very interested in how you are collecting or generating all this information. Please post details on the process. I need similar information in order to compile system call tables into lone, my own programming language which features direct Linux system call support.
I use scripts that parse the information out of Linux user space API headers: the compiler prints all the preprocessor definitions from linux/unistd.h, the "SYS_" definitions are selected and then turned into a C array initializer for a number/name structure.
# makefile
$(call source_to_object,source/lone/lisp/modules/intrinsic/linux.c): $(targets.NR.c)
$(targets.NR.c): $(targets.NR.list) scripts/NR.generate
scripts/NR.generate < $< > $@
$(targets.NR.list): scripts/NR.filter
$(CC) -E -dM -include linux/unistd.h - < /dev/null | scripts/NR.filter > $@
# scripts/NR.filter
grep __NR_ | sed 's/#define //g' | cut -d ' ' -f 1
# scripts/NR.generate
# generates C array initializers like:
# { "read", __NR_read },
while read -r NR; do
printf '{ "%s", %s },\n' "${NR#__NR_}" "${NR}"
done
// source/lone/lisp/modules/intrinsic/linux.c
static struct linux_system_call {
char *symbol;
lone_lisp_integer number;
} linux_system_calls[] = {
/* huge generated array initializer
* with all the system calls found
* on the host platform
*/
#include <lone/lisp/modules/intrinsic/linux/NR.c>
};
Thank you very much :). I am using static analysis of kernel images (vmlinux ELF) that are built with debug information. Each table you see was extracted from a kernel built by my tool, Systrack, that can configure and build kernels that have all the syscalls available. The code is heavily commented and available on GitHub if you are interested: https://github.com/mebeim/systrack
I realized soon in the process that simply looking at kernel sources was not enough to extract everything accurately, specially definition locations. I also wanted this to be a tool to extract syscalls actually implemented from a given kernel image, so that's what it does.
Your approach should be fine, that is what any other language does basically: rely on uapi headers provided by the kernel (just beware that some may be generated at build time inside e.g. include/asm/generated/xxx). You should rely on the headers that are exported when you do `make headers_install`. Also, make sure to have a generic syscall() function that takes an arbitrary syscall number and an arbitrary amount of args to make raw syscalls for the weird ones you don't easily find in uapi headers and you should be good. After all, even in the C library headers some of the "weird" syscalls aren't present sometimes.
I've been using other tables but they were always incomplete and often x86_64 only. This one contains everything: number, symbol, links to kernel implementation, signature, user space ABI registers. And I can select kernel version, kernel binary interface and processor architecture!
I'm very interested in how you are collecting or generating all this information. Please post details on the process. I need similar information in order to compile system call tables into lone, my own programming language which features direct Linux system call support.
I use scripts that parse the information out of Linux user space API headers: the compiler prints all the preprocessor definitions from linux/unistd.h, the "SYS_" definitions are selected and then turned into a C array initializer for a number/name structure.