arch/um/drivers/pty.c

   1 /*
   2  * Copyright (C) 2001, 2002 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include <stdio.h>
   7 #include <unistd.h>
   8 #include <string.h>
   9 #include <errno.h>
  10 #include <termios.h>
  11 #include "chan_user.h"
  12 #include "user.h"
  13 #include "user_util.h"
  14 #include "kern_util.h"
  15 #include "os.h"
  16
  17 struct pty_chan {
  18         void (*announce)(char *dev_name, int dev);
  19         int dev;
  20         int raw;
  21         struct termios tt;
  22         char dev_name[sizeof("/dev/pts/0123456\0")];
  23 };
  24
  25 void *pty_chan_init(char *str, int device, struct chan_opts *opts)
  26 {
  27         struct pty_chan *data;
  28
  29         data = um_kmalloc(sizeof(*data));
  30         if(data == NULL) return(NULL);
  31         *data = ((struct pty_chan) { .announce          = opts->announce,
  32                                      .dev               = device,
  33                                      .raw               = opts->raw });
  34         return(data);
  35 }
  36
  37 int pts_open(int input, int output, int primary, void *d, char **dev_out)
  38 {
  39         struct pty_chan *data = d;
  40         char *dev;
  41         int fd, err;
  42
  43         fd = get_pty();
  44         if(fd < 0){
  45                 printk("open_pts : Failed to open pts\n");
  46                 return(-errno);
  47         }
  48         if(data->raw){
  49                 CATCH_EINTR(err = tcgetattr(fd, &data->tt));
  50                 if(err)
  51                         return(err);
  52
  53                 err = raw(fd);
  54                 if(err)
  55                         return(err);
  56         }
  57
  58         dev = ptsname(fd);
  59         sprintf(data->dev_name, "%s", dev);
  60         *dev_out = data->dev_name;
  61         if (data->announce)
  62                 (*data->announce)(dev, data->dev);
  63         return(fd);
  64 }
  65
  66 int getmaster(char *line)
  67 {
  68         char *pty, *bank, *cp;
  69         int master, err;
  70
  71         pty = &line[strlen("/dev/ptyp")];
  72         for (bank = "pqrs"; *bank; bank++) {
  73                 line[strlen("/dev/pty")] = *bank;
  74                 *pty = '0';
  75                 if (os_stat_file(line, NULL) < 0)
  76                         break;
  77                 for (cp = "0123456789abcdef"; *cp; cp++) {
  78                         *pty = *cp;
  79                         master = os_open_file(line, of_rdwr(OPENFLAGS()), 0);
  80                         if (master >= 0) {
  81                                 char *tp = &line[strlen("/dev/")];
  82
  83                                 /* verify slave side is usable */
  84                                 *tp = 't';
  85                                 err = os_access(line, OS_ACC_RW_OK);
  86                                 *tp = 'p';
  87                                 if(err == 0) return(master);
  88                                 (void) os_close_file(master);
  89                         }
  90                 }
  91         }
  92         return(-1);
  93 }
  94
  95 int pty_open(int input, int output, int primary, void *d, char **dev_out)
  96 {
  97         struct pty_chan *data = d;
  98         int fd, err;
  99         char dev[sizeof("/dev/ptyxx\0")] = "/dev/ptyxx";
 100
 101         fd = getmaster(dev);
 102         if(fd < 0)
 103                 return(-errno);
 104
 105         if(data->raw){
 106                 err = raw(fd);
 107                 if(err)
 108                         return(err);
 109         }
 110
 111         if(data->announce) (*data->announce)(dev, data->dev);
 112
 113         sprintf(data->dev_name, "%s", dev);
 114         *dev_out = data->dev_name;
 115         return(fd);
 116 }
 117
 118 int pty_console_write(int fd, const char *buf, int n, void *d)
 119 {
 120         struct pty_chan *data = d;
 121
 122         return(generic_console_write(fd, buf, n, &data->tt));
 123 }
 124
 125 struct chan_ops pty_ops = {
 126         .type           = "pty",
 127         .init           = pty_chan_init,
 128         .open           = pty_open,
 129         .close          = generic_close,
 130         .read           = generic_read,
 131         .write          = generic_write,
 132         .console_write  = pty_console_write,
 133         .window_size    = generic_window_size,
 134         .free           = generic_free,
 135         .winch          = 0,
 136 };
 137
 138 struct chan_ops pts_ops = {
 139         .type           = "pts",
 140         .init           = pty_chan_init,
 141         .open           = pts_open,
 142         .close          = generic_close,
 143         .read           = generic_read,
 144         .write          = generic_write,
 145         .console_write  = pty_console_write,
 146         .window_size    = generic_window_size,
 147         .free           = generic_free,
 148         .winch          = 0,
 149 };
 150
 151 /*
 152  * Overrides for Emacs so that we follow Linus's tabbing style.
 153  * Emacs will notice this stuff at the end of the file and automatically
 154  * adjust the settings for this buffer only.  This must remain at the end
 155  * of the file.
 156  * ---------------------------------------------------------------------------
 157  * Local variables:
 158  * c-file-style: "linux"
 159  * End:
 160  */