patch-2.1.28 linux/fs/proc/proc_tty.c

• Lines: 184
• Date: Fri Feb 28 15:00:55 1997
• Orig file: v2.1.27/linux/fs/proc/proc_tty.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.1.27/linux/fs/proc/proc_tty.c linux/fs/proc/proc_tty.c
@@ -0,0 +1,183 @@
+/*
+ * proc_tty.c -- handles /proc/tty
+ *
+ * Copyright 1997, Theodore Ts'o
+ */
+
+#include <asm/uaccess.h>
+
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/proc_fs.h>
+#include <linux/stat.h>
+#include <linux/tty.h>
+#include <linux/config.h>
+#include <asm/bitops.h>
+
+extern struct tty_driver *tty_drivers;	/* linked list of tty drivers */
+extern struct tty_ldisc ldiscs[];
+
+
+static int tty_drivers_read_proc(char *page, char **start, off_t off,
+				 int count, void *data);
+static int tty_ldiscs_read_proc(char *page, char **start, off_t off,
+				int count, void *data);
+
+/*
+ * The /proc/tty directory inodes...
+ */
+static struct proc_dir_entry *proc_tty, *proc_tty_ldisc, *proc_tty_driver;
+
+/*
+ * This is the handler for /proc/tty/drivers
+ */
+static int tty_drivers_read_proc(char *page, char **start, off_t off,
+				 int count, void *data)
+{
+	int	len = 0;
+	off_t	begin = 0;
+	struct tty_driver *p;
+	char	range[20], deftype[20];
+	char	*type;
+
+	for (p = tty_drivers; p; p = p->next) {
+		if (p->num > 1)
+			sprintf(range, "%d-%d", p->minor_start,
+				p->minor_start + p->num - 1);
+		else
+			sprintf(range, "%d", p->minor_start);
+		switch (p->type) {
+		case TTY_DRIVER_TYPE_SYSTEM:
+			if (p->subtype == SYSTEM_TYPE_TTY)
+				type = "system:/dev/tty";
+			else if (p->subtype == SYSTEM_TYPE_CONSOLE)
+				type = "system:console";
+			else
+				type = "system";
+			break;
+		case TTY_DRIVER_TYPE_CONSOLE:
+			type = "console";
+			break;
+		case TTY_DRIVER_TYPE_SERIAL:
+			if (p->subtype == 2)
+				type = "serial:callout";
+			else
+				type = "serial";
+			break;
+		case TTY_DRIVER_TYPE_PTY:
+			if (p->subtype == PTY_TYPE_MASTER)
+				type = "pty:master";
+			else if (p->subtype == PTY_TYPE_SLAVE)
+				type = "pty:slave";
+			else
+				type = "pty";
+			break;
+		default:
+			sprintf(deftype, "type:%d.%d", p->type, p->subtype);
+			type = deftype;
+			break;
+		}
+		len += sprintf(page+len, "%-20s /dev/%-8s %3d %7s %s\n",
+			       p->driver_name ? p->driver_name : "",
+			       p->name, p->major, range, type);
+		if (len+begin > off+count)
+			break;
+		if (len+begin < off) {
+			begin += len;
+			len = 0;
+		}
+	}
+	if (off >= len+begin)
+		return 0;
+	*start = page + (begin-off);
+	return ((count < begin+len-off) ? count : begin+len-off);
+}
+
+/*
+ * This is the handler for /proc/tty/ldiscs
+ */
+static int tty_ldiscs_read_proc(char *page, char **start, off_t off,
+				int count, void *data)
+{
+	int	i;
+	int	len = 0;
+	off_t	begin = 0;
+
+	for (i=0; i < NR_LDISCS; i++) {
+		if (!(ldiscs[i].flags & LDISC_FLAG_DEFINED))
+			continue;
+		len += sprintf(page+len, "%-10s %2d\n",
+			       ldiscs[i].name ? ldiscs[i].name : "???", i);
+		if (len+begin > off+count)
+			break;
+		if (len+begin < off) {
+			begin += len;
+			len = 0;
+		}
+	}
+	if (off >= len+begin)
+		return 0;
+	*start = page + (begin-off);
+	return ((count < begin+len-off) ? count : begin+len-off);
+}
+
+/*
+ * Thsi function is called by register_tty_driver() to handle
+ * registering the driver's /proc handler into /proc/tty/driver/<foo>
+ */
+void proc_tty_register_driver(struct tty_driver *driver)
+{
+	struct proc_dir_entry *ent;
+		
+	if ((!driver->read_proc && !driver->write_proc) ||
+	    !driver->driver_name ||
+	    driver->proc_entry)
+		return;
+
+	ent = create_proc_entry(driver->driver_name, 0, proc_tty_driver);
+	if (!ent)
+		return;
+	ent->read_proc = driver->read_proc;
+	ent->write_proc = driver->write_proc;
+	ent->data = driver;
+
+	driver->proc_entry = ent;
+}
+
+/*
+ * This function is called by unregister_tty_driver()
+ */
+void proc_tty_unregister_driver(struct tty_driver *driver)
+{
+	struct proc_dir_entry *ent;
+
+	ent = driver->proc_entry;
+	if (!ent)
+		return;
+		
+	proc_unregister(proc_tty_driver, ent->low_ino);
+	
+	driver->proc_entry = 0;
+	kfree(ent);
+}
+
+/*
+ * Called by proc_root_init() to initialize the /proc/tty subtree
+ */
+void proc_tty_init(void)
+{
+	struct proc_dir_entry *ent;
+	
+	proc_tty = create_proc_entry("tty", S_IFDIR, &proc_root);
+	if (!proc_tty)
+		return;
+	proc_tty_ldisc = create_proc_entry("ldisc", S_IFDIR, proc_tty);
+	proc_tty_driver = create_proc_entry("driver", S_IFDIR, proc_tty);
+
+	ent = create_proc_entry("ldiscs", 0, proc_tty);
+	ent->read_proc = tty_ldiscs_read_proc;
+
+	ent = create_proc_entry("drivers", 0, proc_tty);
+	ent->read_proc = tty_drivers_read_proc;
+}
+