refactor(libc): move Lua an DOOM stubs into shared libc modules

src/userland/libc/posix_io.c

@@ -0,0 +1,153 @@
+#include <stdarg.h>
+#include <stddef.h>
+
+#include "errno.h"
+#include "fcntl.h"
+#include "sys/stat.h"
+#include "syscall.h"
+#include "unistd.h"
+
+static const char *_b_mode_from_flags(int flags) {
+    int accmode = (flags & O_RDWR) ? O_RDWR : ((flags & O_WRONLY) ? O_WRONLY : O_RDONLY);
+
+    if (accmode == O_RDONLY) {
+        return "rb";
+    }
+
+    if (accmode == O_RDWR) {
+        if (flags & O_TRUNC) {
+            return "w+";
+        }
+        if (flags & O_CREAT) {
+            return "a+";
+        }
+        return "r+";
+    }
+
+    if (flags & O_APPEND) {
+        return "ab";
+    }
+    if (flags & O_TRUNC) {
+        return "wb";
+    }
+    if (flags & O_CREAT) {
+        return "wb";
+    }
+    return "wb";
+}
+
+__attribute__((weak)) int open(const char *pathname, int flags, ...) {
+    int fd;
+
+    if (!pathname || pathname[0] == '\0') {
+        errno = EINVAL;
+        return -1;
+    }
+
+    if (flags & O_CREAT) {
+        va_list ap;
+        (void)ap;
+        va_start(ap, flags);
+        (void)va_arg(ap, int);
+        va_end(ap);
+    }
+
+    fd = sys_open(pathname, _b_mode_from_flags(flags));
+    if (fd < 0) {
+        errno = ENOENT;
+        return -1;
+    }
+
+    if (flags & O_APPEND) {
+        (void)sys_seek(fd, 0, SEEK_END);
+    }
+
+    return fd;
+}
+
+__attribute__((weak)) int close(int fd) {
+    if (fd < 0) {
+        errno = EBADF;
+        return -1;
+    }
+    sys_close(fd);
+    return 0;
+}
+
+__attribute__((weak)) ssize_t read(int fd, void *buf, size_t count) {
+    int n;
+    if (fd < 0 || (!buf && count != 0)) {
+        errno = EINVAL;
+        return -1;
+    }
+    n = sys_read(fd, buf, (uint32_t)count);
+    if (n < 0) {
+        errno = EIO;
+        return -1;
+    }
+    return (ssize_t)n;
+}
+
+__attribute__((weak)) ssize_t write(int fd, const void *buf, size_t count) {
+    int n;
+    if (fd < 0 || (!buf && count != 0)) {
+        errno = EINVAL;
+        return -1;
+    }
+
+    if (fd <= 2) {
+        n = sys_write(fd, (const char *)buf, (int)count);
+    } else {
+        n = sys_write_fs(fd, buf, (uint32_t)count);
+    }
+
+    if (n < 0) {
+        errno = EIO;
+        return -1;
+    }
+    return (ssize_t)n;
+}
+
+__attribute__((weak)) off_t lseek(int fd, off_t offset, int whence) {
+    if (fd < 0) {
+        errno = EBADF;
+        return -1;
+    }
+    if (whence != SEEK_SET && whence != SEEK_CUR && whence != SEEK_END) {
+        errno = EINVAL;
+        return -1;
+    }
+
+    if (sys_seek(fd, (int)offset, whence) < 0) {
+        errno = EIO;
+        return -1;
+    }
+    return (off_t)sys_tell(fd);
+}
+
+__attribute__((weak)) int unlink(const char *pathname) {
+    if (!pathname || pathname[0] == '\0') {
+        errno = EINVAL;
+        return -1;
+    }
+    if (sys_delete(pathname) != 0) {
+        errno = ENOENT;
+        return -1;
+    }
+    return 0;
+}
+
+__attribute__((weak)) int isatty(int fd) {
+    return (fd >= 0 && fd <= 2) ? 1 : 0;
+}
+
+__attribute__((weak)) int fstat(int fd, struct stat *statbuf) {
+    if (fd < 0 || !statbuf) {
+        errno = EINVAL;
+        return -1;
+    }
+
+    statbuf->st_size = (int)sys_size(fd);
+    statbuf->st_mode = 0;
+    return 0;
+}