banan-os/libc/unistd.cpp

491 lines
8.0 KiB
C++

#include <BAN/Assert.h>
#include <kernel/Syscall.h>
#include <errno.h>
#include <pwd.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <unistd.h>
char** environ;
extern void init_malloc();
extern "C" void _init_libc(char** _environ)
{
init_malloc();
if (!_environ)
return;
size_t env_count = 0;
while (_environ[env_count])
env_count++;
environ = (char**)malloc(sizeof(char*) * env_count + 1);
for (size_t i = 0; i < env_count; i++)
{
size_t bytes = strlen(_environ[i]) + 1;
environ[i] = (char*)malloc(bytes);
memcpy(environ[i], _environ[i], bytes);
}
environ[env_count] = nullptr;
}
void _exit(int status)
{
syscall(SYS_EXIT, status);
ASSERT_NOT_REACHED();
}
long syscall(long syscall, ...)
{
va_list args;
va_start(args, syscall);
uintptr_t arg1 = va_arg(args, uintptr_t);
uintptr_t arg2 = va_arg(args, uintptr_t);
uintptr_t arg3 = va_arg(args, uintptr_t);
uintptr_t arg4 = va_arg(args, uintptr_t);
uintptr_t arg5 = va_arg(args, uintptr_t);
va_end(args);
long ret = Kernel::syscall(syscall, arg1, arg2, arg3, arg4, arg5);
if (ret < 0)
{
errno = -ret;
return -1;
}
return ret;
}
int close(int fd)
{
return syscall(SYS_CLOSE, fd);
}
ssize_t read(int fildes, void* buf, size_t nbyte)
{
return syscall(SYS_READ, fildes, buf, nbyte);
}
ssize_t write(int fildes, const void* buf, size_t nbyte)
{
return syscall(SYS_WRITE, fildes, buf, nbyte);
}
ssize_t readlink(const char* __restrict path, char* __restrict buf, size_t bufsize)
{
return syscall(SYS_READLINK, path, buf, bufsize);
}
ssize_t readlinkat(int fd, const char* __restrict path, char* __restrict buf, size_t bufsize)
{
return syscall(SYS_READLINKAT, fd, path, buf, bufsize);
}
ssize_t pread(int fildes, void* buf, size_t nbyte, off_t offset)
{
return syscall(SYS_PREAD, fildes, buf, nbyte, offset);
}
off_t lseek(int fildes, off_t offset, int whence)
{
return syscall(SYS_SEEK, fildes, offset, whence);
}
int ftruncate(int fildes, off_t length)
{
return syscall(SYS_TRUNCATE, fildes, length);
}
int dup(int fildes)
{
return syscall(SYS_DUP, fildes);
}
int dup2(int fildes, int fildes2)
{
return syscall(SYS_DUP2, fildes, fildes2);
}
int isatty(int fildes)
{
return syscall(SYS_ISATTY, fildes) >= 0;
}
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 execle(const char* pathname, const char* arg0, ...)
{
va_list ap;
int argc = 0;
if (arg0)
{
va_start(ap, arg0);
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;
}
char** envp = nullptr;
va_start(ap, arg0);
argv[0] = (char*)arg0;
for (int i = 1; i < argc; i++)
argv[i] = va_arg(ap, char*);
argv[argc] = nullptr;
envp = va_arg(ap, char**);
va_end(ap);
return execve(pathname, argv, envp);
}
int execv(const char* pathname, char* const argv[])
{
return execve(pathname, argv, environ);
}
int execve(const char* pathname, char* const argv[], char* const envp[])
{
return syscall(SYS_EXEC, pathname, argv, envp);
}
int execvp(const char* file, char* const argv[])
{
char buffer[1024];
const char* pathname = NULL;
// do path resolution if file doesn't contain /
if (strchr(file, '/') == nullptr)
{
const char* cur = getenv("PATH");
if (!cur)
{
errno = ENOENT;
return -1;
}
while (*cur)
{
const char* end = strchrnul(cur, ':');
size_t len = end - cur;
ASSERT(strlen(file) + 1 + len < sizeof(buffer));
strncpy(buffer, cur, len);
strcat(buffer, "/");
strcat(buffer, file);
struct stat st;
if (stat(buffer, &st) == 0)
{
pathname = buffer;
break;
}
cur = end;
if (*cur)
cur++;
}
}
else
{
pathname = file;
}
if (!pathname)
{
errno = ENOENT;
return -1;
}
return execve(pathname, argv, environ);
}
pid_t fork(void)
{
return syscall(SYS_FORK);
}
int pipe(int fildes[2])
{
return syscall(SYS_PIPE, fildes);
}
unsigned int sleep(unsigned int seconds)
{
unsigned int ret = syscall(SYS_SLEEP, seconds);
if (ret > 0)
errno = EINTR;
return ret;
}
char* getcwd(char* buf, size_t size)
{
if (size == 0)
{
errno = EINVAL;
return nullptr;
}
if ((char*)syscall(SYS_GET_PWD, buf, size) == nullptr)
return nullptr;
setenv("PWD", buf, 1);
return buf;
}
int chdir(const char* path)
{
return syscall(SYS_SET_PWD, path);
}
int chown(const char* path, uid_t owner, gid_t group)
{
return syscall(SYS_CHOWN, path, owner, group);
}
void sync(void)
{
syscall(SYS_SYNC, false);
}
void syncsync(int should_block)
{
syscall(SYS_SYNC, should_block);
}
int unlink(const char* path)
{
return syscall(SYS_UNLINK, path);
}
int rmdir(const char* path)
{
return syscall(SYS_UNLINK, path);
}
char* optarg = nullptr;
int opterr = 1;
int optind = 1;
int optopt = 0;
int getopt(int argc, char* const argv[], const char* optstring)
{
if (optind >= argc)
return -1;
static int idx = 1;
const char* current = argv[optind];
// if "--" is encountered, no more options are parsed
if (idx == -1)
return -1;
// if current is nullptr, does not start with '-' or is string "-", return -1
if (current == nullptr || current[0] != '-' || current[1] == '\0')
return -1;
// if current points to string "--" increment optind and return -1
if (current[1] == '-' && current[2] == '\0')
{
idx = -1;
optind++;
return -1;
}
for (size_t i = 0; optstring[i]; i++)
{
if (optstring[i] == ':')
continue;
if (current[idx] != optstring[i])
continue;
if (optstring[i + 1] == ':')
{
if (current[idx + 1])
{
optarg = const_cast<char*>(current + idx + 1);
optind += 1;
}
else
{
optarg = const_cast<char*>(argv[optind + 1]);
optind += 2;
}
idx = 1;
if (optind > argc)
{
if (opterr && optstring[0] != ':')
fprintf(stderr, "%s: option requires an argument -- %c\n", argv[0], optstring[i]);
optopt = optstring[i];
return optstring[0] == ':' ? ':' : '?';
}
return optstring[i];
}
else
{
if (current[++idx] == '\0')
{
idx = 1;
optind++;
}
return optstring[i];
}
}
if (opterr && optstring[0] != ':')
fprintf(stderr, "%s: illegal option -- %c\n", argv[0], current[idx]);
if (current[++idx] == '\0')
{
idx = 1;
optind++;
}
return '?';
}
pid_t getpid(void)
{
return syscall(SYS_GET_PID);
}
uid_t getuid(void)
{
return syscall(SYS_GET_UID);
}
gid_t getgid(void)
{
return syscall(SYS_GET_GID);
}
uid_t geteuid(void)
{
return syscall(SYS_GET_EUID);
}
gid_t getegid(void)
{
return syscall(SYS_GET_EGID);
}
pid_t getpgrp(void)
{
return getpgid(0);
}
pid_t getpgid(pid_t pid)
{
return syscall(SYS_GET_PGID, pid);
}
int seteuid(uid_t uid)
{
return syscall(SYS_SET_EUID, uid);
}
int setegid(gid_t gid)
{
return syscall(SYS_SET_EGID, gid);
}
int setuid(uid_t uid)
{
return syscall(SYS_SET_UID, uid);
}
int setgid(gid_t gid)
{
return syscall(SYS_SET_GID, gid);
}
int setreuid(uid_t ruid, uid_t euid)
{
return syscall(SYS_SET_REUID, ruid, euid);
}
int setregid(gid_t rgid, gid_t egid)
{
return syscall(SYS_SET_REGID, rgid, egid);
}
pid_t setpgrp(void)
{
setpgid(0, 0);
return getpgrp();
}
int setpgid(pid_t pid, pid_t pgid)
{
return syscall(SYS_SET_PGID, pid, pgid);
}
int tcsetpgrp(int fildes, pid_t pgid_id)
{
return syscall(SYS_TCSETPGRP, fildes, pgid_id);
}
char* getlogin(void)
{
static char buffer[LOGIN_NAME_MAX];
auto* pw = getpwuid(geteuid());
if (pw == nullptr)
return nullptr;
strncpy(buffer, pw->pw_name, LOGIN_NAME_MAX - 1);
buffer[LOGIN_NAME_MAX - 1] = '\0';
endpwent();
return buffer;
}