root/kernel/syscalls/fcntl.c

/* */

DEFINITIONS

1. sys_fcntl

   1 /*
   2  * fiwix/kernel/syscalls/fcntl.c
   3  *
   4  * Copyright 2018, Jordi Sanfeliu. All rights reserved.
   5  * Distributed under the terms of the Fiwix License.
   6  */
   7 
   8 #include <fiwix/syscalls.h>
   9 #include <fiwix/fcntl.h>
  10 #include <fiwix/locks.h>
  11 #include <fiwix/errno.h>
  12 
  13 #ifdef __DEBUG__
  14 #include <fiwix/stdio.h>
  15 #include <fiwix/process.h>
  16 #endif /*__DEBUG__ */
  17 
  18 int sys_fcntl(int ufd, int cmd, unsigned long int arg)
  19 {
  20         int new_ufd, errno;
  21 
  22 #ifdef __DEBUG__
  23         printk("(pid %d) sys_fcntl(%d, %d, 0x%08x)\n", current->pid, ufd, cmd, arg);
  24 #endif /*__DEBUG__ */
  25 
  26         CHECK_UFD(ufd);
  27         switch(cmd) {
  28                 case F_DUPFD:
  29                         CHECK_UFD(ufd);
  30                         if(arg >= OPEN_MAX) {
  31                                 return -EINVAL;
  32                         }
  33                         if((new_ufd = get_new_user_fd(arg)) < 0) {
  34                                 return new_ufd;
  35                         }
  36                         current->fd[new_ufd] = current->fd[ufd];
  37                         fd_table[current->fd[new_ufd]].count++;
  38 #ifdef __DEBUG__
  39                         printk("\t--> returning %d\n", new_ufd);
  40 #endif /*__DEBUG__ */
  41                         return new_ufd;
  42                 case F_GETFD:
  43                         return (current->fd_flags[ufd] & FD_CLOEXEC);
  44                 case F_SETFD:
  45                         current->fd_flags[ufd] = (arg & FD_CLOEXEC);
  46                         break;
  47                 case F_GETFL:
  48                         return fd_table[current->fd[ufd]].flags;
  49                 case F_SETFL:
  50                         fd_table[current->fd[ufd]].flags &= ~(O_APPEND | O_NONBLOCK);
  51                         fd_table[current->fd[ufd]].flags |= arg & (O_APPEND | O_NONBLOCK);
  52                         break;
  53                 case F_GETLK:
  54                 case F_SETLK:
  55                 case F_SETLKW:
  56                         if((errno = check_user_area(VERIFY_READ, (void *)arg, sizeof(struct flock)))) {
  57                                 return errno;
  58                         }
  59                         return posix_lock(ufd, cmd, (struct flock *)arg);
  60                 default:
  61                         return -EINVAL;
  62         }
  63         return 0;
  64 }

/* */