banan-os/libc/unistd.cpp

203 lines
4.0 KiB
C++

#include <BAN/Assert.h>
#include <kernel/Syscall.h>
#include <errno.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/syscall.h>
#include <unistd.h>
extern "C" void _init_stdio();
extern "C" void _init_libc()
{
_init_stdio();
}
void _exit(int status)
{
syscall(SYS_EXIT, status);
ASSERT_NOT_REACHED();
}
long syscall(long syscall, ...)
{
va_list args;
va_start(args, syscall);
long ret = -1;
switch (syscall)
{
case SYS_EXIT:
{
int exit_code = va_arg(args, int);
ret = Kernel::syscall(SYS_EXIT, exit_code);
break;
}
case SYS_READ:
{
int fd = va_arg(args, int);
void* buffer = va_arg(args, void*);
size_t offset = va_arg(args, size_t);
size_t bytes = va_arg(args, size_t);
ret = Kernel::syscall(SYS_READ, fd, (uintptr_t)buffer, offset, bytes);
break;
}
case SYS_WRITE:
{
int fd = va_arg(args, int);
const char* string = va_arg(args, const char*);
size_t offset = va_arg(args, size_t);
size_t bytes = va_arg(args, size_t);
ret = Kernel::syscall(SYS_WRITE, fd, (uintptr_t)string, offset, bytes);
break;
}
case SYS_TERMID:
{
char* buffer = va_arg(args, char*);
ret = Kernel::syscall(SYS_TERMID, (uintptr_t)buffer);
break;
}
case SYS_CLOSE:
{
int fd = va_arg(args, int);
ret = Kernel::syscall(SYS_CLOSE, fd);
break;
}
case SYS_OPEN:
{
const char* path = va_arg(args, const char*);
int oflags = va_arg(args, int);
ret = Kernel::syscall(SYS_OPEN, (uintptr_t)path, oflags);
break;
}
case SYS_ALLOC:
{
size_t bytes = va_arg(args, size_t);
ret = Kernel::syscall(SYS_ALLOC, bytes);
break;
}
case SYS_FREE:
{
void* ptr = va_arg(args, void*);
ret = Kernel::syscall(SYS_FREE, (uintptr_t)ptr);
break;
}
case SYS_SEEK:
{
int fd = va_arg(args, int);
off_t offset = va_arg(args, off_t);
int whence = va_arg(args, int);
ret = Kernel::syscall(SYS_SEEK, fd, offset, whence);
break;
}
case SYS_TELL:
{
int fd = va_arg(args, int);
ret = Kernel::syscall(SYS_TELL, fd);
break;
}
case SYS_GET_TERMIOS:
{
struct termios* termios = va_arg(args, struct termios*);
ret = Kernel::syscall(SYS_GET_TERMIOS, (uintptr_t)termios);
break;
}
case SYS_SET_TERMIOS:
{
const struct termios* termios = va_arg(args, const struct termios*);
ret = Kernel::syscall(SYS_SET_TERMIOS, (uintptr_t)termios);
break;
}
case SYS_FORK:
{
ret = Kernel::syscall(SYS_FORK);
break;
}
case SYS_SLEEP:
{
unsigned int seconds = va_arg(args, unsigned int);
ret = Kernel::syscall(SYS_SLEEP, seconds);
break;
}
case SYS_EXEC:
{
const char* pathname = va_arg(args, const char*);
const char* const* argv = va_arg(args, const char* const*);
const char* const* envp = va_arg(args, const char* const*);
ret = Kernel::syscall(SYS_EXEC, (uintptr_t)pathname, (uintptr_t)argv, (uintptr_t)envp);
break;
}
case SYS_REALLOC:
{
void* ptr = va_arg(args, void*);
size_t size = va_arg(args, size_t);
ret = Kernel::syscall(SYS_REALLOC, (uintptr_t)ptr, size);
break;
}
default:
puts("LibC: Unhandeled syscall");
ret = -ENOSYS;
break;
}
va_end(args);
if (ret < 0)
{
errno = -ret;
return -1;
}
return ret;
}
int execl(const char* pathname, const char* arg0, ...)
{
if (arg0 == nullptr)
{
char* temp = nullptr;
return execv(pathname, &temp);
}
va_list ap;
va_start(ap, arg0);
int argc = 1;
while (va_arg(ap, const char*))
argc++;
va_end(ap);
char** argv = (char**)malloc(sizeof(char*) * (argc + 1));
if (argv == nullptr)
{
errno = ENOMEM;
return -1;
}
va_start(ap, arg0);
argv[0] = (char*)arg0;
for (int i = 1; i < argc; i++)
argv[i] = va_arg(ap, char*);
argv[argc] = nullptr;
va_end(ap);
return execv(pathname, argv);
}
int execv(const char* pathname, char* const argv[])
{
return syscall(SYS_EXEC, pathname, argv, nullptr);
}
pid_t fork(void)
{
return syscall(SYS_FORK);
}
unsigned int sleep(unsigned int seconds)
{
return syscall(SYS_SLEEP, seconds);
}