rumpk/vendor/mksh/stubs_mksh.c

285 lines
8.8 KiB
C

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/times.h>
#include <sys/wait.h>
#include <fcntl.h>
#include <unistd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <dirent.h>
#include <errno.h>
#include <string.h>
#include <setjmp.h>
#include <termios.h>
#include <stdarg.h>
extern long syscall(long nr, long a0, long a1, long a2);
long k_handle_syscall(long nr, long a0, long a1, long a2) {
return syscall(nr, a0, a1, a2);
}
// Globals
char **environ = NULL;
// Safe Userland Allocator (Bump Pointer with Headers)
#define HEAP_SIZE (32 * 1024 * 1024)
static char heap_memory[HEAP_SIZE];
static size_t heap_ptr = 0;
typedef struct {
size_t size;
size_t magic;
} BlockHeader;
#define ALLOC_MAGIC 0xCAFEBABE
void *malloc(size_t size) {
if (size == 0) return NULL;
// Align total size (header + data) to 16 bytes
size_t required = size + sizeof(BlockHeader);
size_t aligned_total = (required + 15) & ~15;
if (heap_ptr + aligned_total > HEAP_SIZE) return NULL;
BlockHeader *hdr = (BlockHeader *)&heap_memory[heap_ptr];
hdr->size = size;
hdr->magic = ALLOC_MAGIC;
void *ptr = (void *)((char *)hdr + sizeof(BlockHeader));
heap_ptr += aligned_total;
return ptr;
}
void free(void *ptr) {
// No-op bump allocator
}
void *realloc(void *ptr, size_t size) {
if (!ptr) return malloc(size);
if (size == 0) return NULL; // Standard says free.. or return NULL? mksh expects NULL or ptr.
// Get header
BlockHeader *hdr = (BlockHeader *)((char *)ptr - sizeof(BlockHeader));
if (hdr->magic != ALLOC_MAGIC) {
// Corrupted ptr? return NULL or fail.
return NULL;
}
// Optimization: If it's the LAST block, simple extend? (Not implemented for simplicity)
void *new_ptr = malloc(size);
if (!new_ptr) return NULL;
size_t copy_size = (hdr->size < size) ? hdr->size : size;
memcpy(new_ptr, ptr, copy_size);
return new_ptr;
}
void *calloc(size_t nmemb, size_t size) {
size_t total = nmemb * size;
void *ptr = malloc(total);
if (ptr) memset(ptr, 0, total);
return ptr;
}
// Stubs
int fstat(int fd, struct stat *buf) { return 0; }
int lstat(const char *path, struct stat *buf) { return 0; }
int stat(const char *path, struct stat *buf) { return 0; }
int sigemptyset(sigset_t *set) { return 0; }
int sigaddset(sigset_t *set, int signum) { return 0; }
int sigprocmask(int how, const sigset_t *set, sigset_t *oldset) { return 0; }
int sigaction(int signum, const struct sigaction *act, struct sigaction *oldact) {
if (oldact) {
// Initialize to safe defaults - no handler installed
memset(oldact, 0, sizeof(struct sigaction));
oldact->sa_handler = SIG_DFL; // Default handler
}
return 0;
}
int sigsuspend(const sigset_t *mask) { return -1; }
int kill(pid_t pid, int sig) { return 0; }
unsigned int alarm(unsigned int seconds) { return 0; }
off_t lseek(int fd, off_t offset, int whence) { return 0; }
// ssize_t read(int fd, void *buf, size_t count) { return 0; } // In libc.nim
// ssize_t write(int fd, const void *buf, size_t count) { return 0; } // In clib.c
// int open(const char *pathname, int flags, ...) { return -1; } // In libc.nim
// int close(int fd) { return 0; } // In libc.nim
int pipe(int pipefd[2]) { return -1; }
int dup2(int oldfd, int newfd) { return newfd; }
extern void console_write(const void* p, unsigned long len);
static void ksh_debug(const char* s) {
console_write(s, (unsigned long)strlen(s));
}
int fcntl(int fd, int cmd, ...) {
ksh_debug("[mksh] fcntl called\n");
va_list args;
va_start(args, cmd);
long arg = va_arg(args, long);
va_end(args);
int res = (int)syscall(0x206, (long)fd, (long)cmd, arg);
ksh_debug("[mksh] fcntl returning\n");
return res;
}
int ioctl(int fd, unsigned long request, ...) { return 0; }
// int execve(const char *pathname, char *const argv[], char *const envp[]) { return -1; } // In clib.c
// pid_t fork(void) { return -1; } // In clib.c
pid_t waitpid(pid_t pid, int *status, int options) { return -1; }
pid_t getpid(void) { return 1; }
pid_t getppid(void) { return 0; }
uid_t getuid(void) { return 0; }
uid_t geteuid(void) { return 0; }
gid_t getgid(void) { return 0; }
gid_t getegid(void) { return 0; }
pid_t getpgrp(void) { return 1; }
int setuid(uid_t uid) { return 0; }
int setgid(gid_t gid) { return 0; }
int seteuid(uid_t uid) { return 0; }
int setegid(gid_t gid) { return 0; }
int setpgid(pid_t pid, pid_t pgid) { return 0; }
int tcgetattr(int fd, struct termios *termios_p) {
if (termios_p) {
// Initialize with safe defaults (using numeric values to avoid missing constants)
memset(termios_p, 0, sizeof(struct termios));
// Set basic flags for canonical mode
termios_p->c_iflag = 0x0100; // ICRNL
termios_p->c_oflag = 0x0001 | 0x0004; // OPOST | ONLCR
termios_p->c_cflag = 0x0030 | 0x0080; // CS8 | CREAD
termios_p->c_lflag = ISIG | ICANON | ECHO; // These should be defined
// Set control characters
termios_p->c_cc[VINTR] = 3; // Ctrl-C
termios_p->c_cc[VQUIT] = 28; // Ctrl-backslash
termios_p->c_cc[VERASE] = 127; // DEL
termios_p->c_cc[VKILL] = 21; // Ctrl-U
termios_p->c_cc[VEOF] = 4; // Ctrl-D
termios_p->c_cc[VMIN] = 1;
termios_p->c_cc[VTIME] = 0;
}
return 0;
}
int tcsetattr(int fd, int optional_actions, const struct termios *termios_p) { return 0; }
pid_t tcgetpgrp(int fd) { return 1; }
int tcsetpgrp(int fd, pid_t pgrp) { return 0; }
int isatty(int fd) { return 1; }
int access(const char *pathname, int mode) { return -1; }
int unlink(const char *pathname) { return -1; }
int rename(const char *oldpath, const char *newpath) { return -1; }
int rmdir(const char *pathname) { return -1; }
int chdir(const char *path) { return 0; }
char *getcwd(char *buf, size_t size) {
if (size > 1) { buf[0]='/'; buf[1]='\0'; return buf; }
return NULL;
}
int mkdir(const char *pathname, mode_t mode) { return -1; }
time_t time(time_t *tloc) { return 0; }
clock_t times(struct tms *buf) { return 0; }
unsigned int sleep(unsigned int seconds) { return 0; }
DIR *opendir(const char *name) { return NULL; }
struct dirent *readdir(DIR *dirp) { return NULL; }
int closedir(DIR *dirp) { return 0; }
ssize_t readlink(const char *pathname, char *buf, size_t objsiz) { return -1; }
struct passwd *getpwnam(const char *name) { return NULL; }
// qsort
void qsort(void *base, size_t nmemb, size_t size, int (*compar)(const void *, const void *)) {
if (nmemb < 2 || size == 0) return;
char *b = (char *)base;
char *tmp = malloc(size);
for (size_t i = 0; i < nmemb - 1; i++) {
for (size_t j = 0; j < nmemb - i - 1; j++) {
if (compar(b + j * size, b + (j + 1) * size) > 0) {
// swap
memcpy(tmp, b + j * size, size);
memcpy(b + j * size, b + (j + 1) * size, size);
memcpy(b + (j + 1) * size, tmp, size);
}
}
}
free(tmp);
}
// strstr
char *strstr(const char *haystack, const char *needle) {
if (!*needle) return (char *)haystack;
for (char *p = (char *)haystack; *p; p++) {
if (*p == *needle) {
char *h = p, *n = (char *)needle;
while (*h && *n && *h == *n) { h++; n++; }
if (!*n) return p;
}
}
return NULL;
}
mode_t umask(mode_t mask) { return 0; }
int c_ulimit(const char **wp) { return 0; }
int setjmp(jmp_buf env) {
__asm__ volatile (
"sd ra, 0(%0)\n"
"sd sp, 8(%0)\n"
"sd s0, 16(%0)\n"
"sd s1, 24(%0)\n"
"sd s2, 32(%0)\n"
"sd s3, 40(%0)\n"
"sd s4, 48(%0)\n"
"sd s5, 56(%0)\n"
"sd s6, 64(%0)\n"
"sd s7, 72(%0)\n"
"sd s8, 80(%0)\n"
"sd s9, 88(%0)\n"
"sd s10, 96(%0)\n"
"sd s11, 104(%0)\n"
"li a0, 0\n"
: : "r"(env) : "memory", "a0"
);
return 0;
}
void longjmp(jmp_buf env, int val) {
__asm__ volatile (
"ld ra, 0(%0)\n"
"ld sp, 8(%0)\n"
"ld s0, 16(%0)\n"
"ld s1, 24(%0)\n"
"ld s2, 32(%0)\n"
"ld s3, 40(%0)\n"
"ld s4, 48(%0)\n"
"ld s5, 56(%0)\n"
"ld s6, 64(%0)\n"
"ld s7, 72(%0)\n"
"ld s8, 80(%0)\n"
"ld s9, 88(%0)\n"
"ld s10, 96(%0)\n"
"ld s11, 104(%0)\n"
"mv a0, %1\n"
"seqz t0, a0\n"
"add a0, a0, t0\n"
: : "r"(env), "r"(val) : "memory", "a0", "t0"
);
// Note: longjmp should not return. In this freestanding env,
// the asm above ends with registers restored and we jump back.
// However, to be extra safe we could add a ret at the end of asm.
__asm__ volatile("ret");
}
void exit(int status) {
syscall(0x01, (long)status, 0, 0);
while(1);
}