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