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 static 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 static int pts_open(int input, int output, int primary, void *d,
  38                     char **dev_out)
  39 {
  40         struct pty_chan *data = d;
  41         char *dev;
  42         int fd, err;
  43
  44         fd = get_pty();
  45         if(fd < 0){
  46                 err = -errno;
  47                 printk("open_pts : Failed to open pts\n");
  48                 return err;
  49         }
  50         if(data->raw){
  51                 CATCH_EINTR(err = tcgetattr(fd, &data->tt));
  52                 if(err)
  53                         return(err);
  54
  55                 err = raw(fd);
  56                 if(err)
  57                         return(err);
  58         }
  59
  60         dev = ptsname(fd);
  61         sprintf(data->dev_name, "%s", dev);
  62         *dev_out = data->dev_name;
  63         if (data->announce)
  64                 (*data->announce)(dev, data->dev);
  65         return(fd);
  66 }
  67
  68 static int getmaster(char *line)
  69 {
  70         char *pty, *bank, *cp;
  71         int master, err;
  72
  73         pty = &line[strlen("/dev/ptyp")];
  74         for (bank = "pqrs"; *bank; bank++) {
  75                 line[strlen("/dev/pty")] = *bank;
  76                 *pty = '0';
  77                 if (os_stat_file(line, NULL) < 0)
  78                         break;
  79                 for (cp = "0123456789abcdef"; *cp; cp++) {
  80                         *pty = *cp;
  81                         master = os_open_file(line, of_rdwr(OPENFLAGS()), 0);
  82                         if (master >= 0) {
  83                                 char *tp = &line[strlen("/dev/")];
  84
  85                                 /* verify slave side is usable */
  86                                 *tp = 't';
  87                                 err = os_access(line, OS_ACC_RW_OK);
  88                                 *tp = 'p';
  89                                 if(err == 0) return(master);
  90                                 (void) os_close_file(master);
  91                         }
  92                 }
  93         }
  94         return(-1);
  95 }
  96
  97 static int pty_open(int input, int output, int primary, void *d,
  98                     char **dev_out)
  99 {
 100         struct pty_chan *data = d;
 101         int fd, err;
 102         char dev[sizeof("/dev/ptyxx\0")] = "/dev/ptyxx";
 103
 104         fd = getmaster(dev);
 105         if(fd < 0)
 106                 return(-errno);
 107
 108         if(data->raw){
 109                 err = raw(fd);
 110                 if(err)
 111                         return(err);
 112         }
 113
 114         if(data->announce) (*data->announce)(dev, data->dev);
 115
 116         sprintf(data->dev_name, "%s", dev);
 117         *dev_out = data->dev_name;
 118         return(fd);
 119 }
 120
 121 static int pty_console_write(int fd, const char *buf, int n, void *d)
 122 {
 123         struct pty_chan *data = d;
 124
 125         return(generic_console_write(fd, buf, n, &data->tt));
 126 }
 127
 128 struct chan_ops pty_ops = {
 129         .type           = "pty",
 130         .init           = pty_chan_init,
 131         .open           = pty_open,
 132         .close          = generic_close,
 133         .read           = generic_read,
 134         .write          = generic_write,
 135         .console_write  = pty_console_write,
 136         .window_size    = generic_window_size,
 137         .free           = generic_free,
 138         .winch          = 0,
 139 };
 140
 141 struct chan_ops pts_ops = {
 142         .type           = "pts",
 143         .init           = pty_chan_init,
 144         .open           = pts_open,
 145         .close          = generic_close,
 146         .read           = generic_read,
 147         .write          = generic_write,
 148         .console_write  = pty_console_write,
 149         .window_size    = generic_window_size,
 150         .free           = generic_free,
 151         .winch          = 0,
 152 };
 153
 154 /*
 155  * Overrides for Emacs so that we follow Linus's tabbing style.
 156  * Emacs will notice this stuff at the end of the file and automatically
 157  * adjust the settings for this buffer only.  This must remain at the end
 158  * of the file.
 159  * ---------------------------------------------------------------------------
 160  * Local variables:
 161  * c-file-style: "linux"
 162  * End:
 163  */