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