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