root/kernel/syscalls/fchown.c

/* */

---

DEFINITIONS

This source file includes following definitions.

1. sys_fchown

---

   1 /*
   2  * fiwix/kernel/syscalls/fchown.c
   3  *
   4  * Copyright 2018-2022, Jordi Sanfeliu. All rights reserved.
   5  * Distributed under the terms of the Fiwix License.
   6  */
   7 
   8 #include <fiwix/kernel.h>
   9 #include <fiwix/types.h>
  10 #include <fiwix/fs.h>
  11 #include <fiwix/stat.h>
  12 #include <fiwix/process.h>
  13 #include <fiwix/errno.h>
  14 
  15 #ifdef __DEBUG__
  16 #include <fiwix/stdio.h>
  17 #endif /*__DEBUG__ */
  18 
  19 int sys_fchown(unsigned int ufd, __uid_t owner, __gid_t group)
  20 {
  21         struct inode *i;
  22 
  23 #ifdef __DEBUG__
  24         printk("(pid %d) sys_fchown(%d, %d, %d)\n", current->pid, ufd, owner, group);
  25 #endif /*__DEBUG__ */
  26 
  27         CHECK_UFD(ufd);
  28         i = fd_table[current->fd[ufd]].inode;
  29 
  30         if(IS_RDONLY_FS(i)) {
  31                 return -EROFS;
  32         }
  33         if(check_user_permission(i)) {
  34                 return -EPERM;
  35         }
  36 
  37         if(owner == (__uid_t)-1) {
  38                 owner = i->i_uid;
  39         } else {
  40                 i->i_mode &= ~(S_ISUID);
  41         }
  42         if(group == (__gid_t)-1) {
  43                 group = i->i_gid;
  44         } else {
  45                 i->i_mode &= ~(S_ISGID);
  46         }
  47 
  48         i->i_uid = owner;
  49         i->i_gid = group;
  50         i->i_ctime = CURRENT_TIME;
  51         i->dirty = 1;
  52         return 0;
  53 }

---

/* */