arch/um/drivers/fd.c

   1 /*
   2  * Copyright (C) 2001 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <unistd.h>
   9 #include <termios.h>
  10 #include <errno.h>
  11 #include "user.h"
  12 #include "user_util.h"
  13 #include "chan_user.h"
  14
  15 struct fd_chan {
  16         int fd;
  17         int raw;
  18         struct termios tt;
  19         char str[sizeof("1234567890\0")];
  20 };
  21
  22 static void *fd_init(char *str, int device, struct chan_opts *opts)
  23 {
  24         struct fd_chan *data;
  25         char *end;
  26         int n;
  27
  28         if(*str != ':'){
  29                 printk("fd_init : channel type 'fd' must specify a file "
  30                        "descriptor\n");
  31                 return(NULL);
  32         }
  33         str++;
  34         n = strtoul(str, &end, 0);
  35         if((*end != '\0') || (end == str)){
  36                 printk("fd_init : couldn't parse file descriptor '%s'\n", str);
  37                 return(NULL);
  38         }
  39         data = um_kmalloc(sizeof(*data));
  40         if(data == NULL) return(NULL);
  41         *data = ((struct fd_chan) { .fd         = n,
  42                                     .raw        = opts->raw });
  43         return(data);
  44 }
  45
  46 static int fd_open(int input, int output, int primary, void *d, char **dev_out)
  47 {
  48         struct fd_chan *data = d;
  49         int err;
  50
  51         if(data->raw && isatty(data->fd)){
  52                 CATCH_EINTR(err = tcgetattr(data->fd, &data->tt));
  53                 if(err)
  54                         return(err);
  55
  56                 err = raw(data->fd);
  57                 if(err)
  58                         return(err);
  59         }
  60         sprintf(data->str, "%d", data->fd);
  61         *dev_out = data->str;
  62         return(data->fd);
  63 }
  64
  65 static void fd_close(int fd, void *d)
  66 {
  67         struct fd_chan *data = d;
  68         int err;
  69
  70         if(data->raw && isatty(fd)){
  71                 CATCH_EINTR(err = tcsetattr(fd, TCSAFLUSH, &data->tt));
  72                 if(err)
  73                         printk("Failed to restore terminal state - "
  74                                "errno = %d\n", -err);
  75                 data->raw = 0;
  76         }
  77 }
  78
  79 static int fd_console_write(int fd, const char *buf, int n, void *d)
  80 {
  81         struct fd_chan *data = d;
  82
  83         return(generic_console_write(fd, buf, n, &data->tt));
  84 }
  85
  86 struct chan_ops fd_ops = {
  87         .type           = "fd",
  88         .init           = fd_init,
  89         .open           = fd_open,
  90         .close          = fd_close,
  91         .read           = generic_read,
  92         .write          = generic_write,
  93         .console_write  = fd_console_write,
  94         .window_size    = generic_window_size,
  95         .free           = generic_free,
  96         .winch          = 1,
  97 };
  98
  99 /*
 100  * Overrides for Emacs so that we follow Linus's tabbing style.
 101  * Emacs will notice this stuff at the end of the file and automatically
 102  * adjust the settings for this buffer only.  This must remain at the end
 103  * of the file.
 104  * ---------------------------------------------------------------------------
 105  * Local variables:
 106  * c-file-style: "linux"
 107  * End:
 108  */