Implement mknodat

mehfooz09 · Feb 3, 2020 · 6b5a148 · 6b5a148
1 parent c87e93d
commit 6b5a148
Show file tree

Hide file tree

Showing 5 changed files with 15 additions and 6 deletions.
diff --git a/fs/generic.c b/fs/generic.c
@@ -195,14 +195,14 @@ int generic_symlinkat(const char *target, struct fd *at, const char *link_raw) {
     return err;
 }
 
-int generic_mknod(const char *path_raw, mode_t_ mode, dev_t_ dev) {
+int generic_mknodat(struct fd *at, const char *path_raw, mode_t_ mode, dev_t_ dev) {
     if (S_ISDIR(mode) || S_ISLNK(mode))
         return _EINVAL;
     if (!superuser() && (S_ISBLK(mode) || S_ISCHR(mode)))
         return _EPERM;
 
     char path[MAX_PATH];
-    int err = path_normalize(AT_PWD, path_raw, path, N_SYMLINK_NOFOLLOW | N_PARENT_DIR_WRITE);
+    int err = path_normalize(at, path_raw, path, N_SYMLINK_NOFOLLOW | N_PARENT_DIR_WRITE);
     if (err < 0)
         return err;
     struct mount *mount = find_mount_and_trim_path(path);

diff --git a/kernel/calls.c b/kernel/calls.c
@@ -173,6 +173,7 @@ syscall_t syscall_table[] = {
     [291] = (syscall_t) syscall_stub, // inotify_init
     [295] = (syscall_t) sys_openat,
     [296] = (syscall_t) sys_mkdirat,
+    [297] = (syscall_t) sys_mknodat,
     [298] = (syscall_t) sys_fchownat,
     [300] = (syscall_t) sys_fstatat64,
     [301] = (syscall_t) sys_unlinkat,

diff --git a/kernel/calls.h b/kernel/calls.h
@@ -117,6 +117,7 @@ dword_t sys_renameat2(fd_t src_at_f, addr_t src_addr, fd_t dst_at_f, addr_t dst_
 dword_t sys_symlink(addr_t target_addr, addr_t link_addr);
 dword_t sys_symlinkat(addr_t target_addr, fd_t at_f, addr_t link_addr);
 dword_t sys_mknod(addr_t path_addr, mode_t_ mode, dev_t_ dev);
+dword_t sys_mknodat(fd_t at_f, addr_t path_addr, mode_t_ mode, dev_t_ dev);
 dword_t sys_access(addr_t path_addr, dword_t mode);
 dword_t sys_faccessat(fd_t at_f, addr_t path, mode_t_ mode, dword_t flags);
 dword_t sys_readlink(addr_t path, addr_t buf, dword_t bufsize);

diff --git a/kernel/fs.c b/kernel/fs.c
@@ -193,13 +193,20 @@ dword_t sys_symlink(addr_t target_addr, addr_t link_addr) {
     return sys_symlinkat(target_addr, AT_FDCWD_, link_addr);
 }
 
-dword_t sys_mknod(addr_t path_addr, mode_t_ mode, dev_t_ dev) {
+dword_t sys_mknodat(fd_t at_f, addr_t path_addr, mode_t_ mode, dev_t_ dev) {
     char path[MAX_PATH];
     if (user_read_string(path_addr, path, sizeof(path)))
         return _EFAULT;
-    STRACE("mknod(\"%s\", %#x, %#x)", path, mode, dev);
+    STRACE("mknodat(%d, \"%s\", %#x, %#x)", at_f, path, mode, dev);
     apply_umask(&mode);
-    return generic_mknod(path, mode, dev);
+    struct fd *at = at_fd(at_f);
+    if (at == NULL)
+        return _EBADF;
+    return generic_mknodat(at, path, mode, dev);
+}
+
+dword_t sys_mknod(addr_t path_addr, mode_t_ mode, dev_t_ dev) {
+    return sys_mknodat(AT_FDCWD_, path_addr, mode, dev);
 }
 
 dword_t sys_read(fd_t fd_no, addr_t buf_addr, dword_t size) {

diff --git a/kernel/fs.h b/kernel/fs.h
@@ -52,7 +52,7 @@ int generic_unlinkat(struct fd *at, const char *path);
 int generic_rmdirat(struct fd *at, const char *path);
 int generic_renameat(struct fd *src_at, const char *src, struct fd *dst_at, const char *dst);
 int generic_symlinkat(const char *target, struct fd *at, const char *link);
-int generic_mknod(const char *path, mode_t_ mode, dev_t_ dev);
+int generic_mknodat(struct fd *at, const char *path, mode_t_ mode, dev_t_ dev);
 #define AC_R 4
 #define AC_W 2
 #define AC_X 1