Staging: add speakup to the staging directory

Speakup is a kernel based screen review package for the linux operating
system.  It allows blind users to interact with applications on the
linux console by means of synthetic speech.

The authors and maintainers of this code include the following:

Kirk Reiser, Andy Berdan, John Covici, Brian and
David Borowski, Christopher Brannon, Samuel Thibault and William Hubbs.

Signed-off-by: William Hubbs <w.d.hubbs@gmail.com>
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 155 insertions, 0 deletions

diff --git a/drivers/staging/speakup/selection.c b/drivers/staging/speakup/selection.c
new file mode 100644
index 00000000000..1b865ff00bc
--- /dev/null
+++ b/drivers/staging/speakup/selection.c
@@ -0,0 +1,155 @@
+#include <linux/slab.h> /* for kmalloc */
+#include <linux/consolemap.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/selection.h>
+
+#include "speakup.h"
+
+/* ------ cut and paste ----- */
+/* Don't take this from <ctype.h>: 011-015 on the screen aren't spaces */
+#define ishardspace(c)      ((c) == ' ')
+
+unsigned short xs, ys, xe, ye; /* our region points */
+
+/* Variables for selection control. */
+/* must not be disallocated */
+struct vc_data *spk_sel_cons;
+/* cleared by clear_selection */
+static int sel_start = -1;
+static int sel_end;
+static int sel_buffer_lth;
+static char *sel_buffer;
+
+static unsigned char sel_pos(int n)
+{
+	return inverse_translate(spk_sel_cons, screen_glyph(spk_sel_cons, n), 0);
+}
+
+void speakup_clear_selection(void)
+{
+	sel_start = -1;
+}
+
+/* does screen address p correspond to character at LH/RH edge of screen? */
+static int atedge(const int p, int size_row)
+{
+	return (!(p % size_row) || !((p + 2) % size_row));
+}
+
+/* constrain v such that v <= u */
+static unsigned short limit(const unsigned short v, const unsigned short u)
+{
+	return (v > u) ? u : v;
+}
+
+int speakup_set_selection(struct tty_struct *tty)
+{
+	int new_sel_start, new_sel_end;
+	char *bp, *obp;
+	int i, ps, pe;
+	struct vc_data *vc = vc_cons[fg_console].d;
+
+	xs = limit(xs, vc->vc_cols - 1);
+	ys = limit(ys, vc->vc_rows - 1);
+	xe = limit(xe, vc->vc_cols - 1);
+	ye = limit(ye, vc->vc_rows - 1);
+	ps = ys * vc->vc_size_row + (xs << 1);
+	pe = ye * vc->vc_size_row + (xe << 1);
+
+	if (ps > pe) {
+		/* make sel_start <= sel_end */
+		int tmp = ps;
+		ps = pe;
+		pe = tmp;
+	}
+
+	if (spk_sel_cons != vc_cons[fg_console].d) {
+		speakup_clear_selection();
+		spk_sel_cons = vc_cons[fg_console].d;
+		printk(KERN_WARNING
+			"Selection: mark console not the same as cut\n");
+		return -EINVAL;
+	}
+
+	new_sel_start = ps;
+	new_sel_end = pe;
+
+	/* select to end of line if on trailing space */
+	if (new_sel_end > new_sel_start &&
+	    !atedge(new_sel_end, vc->vc_size_row) &&
+	    ishardspace(sel_pos(new_sel_end))) {
+		for (pe = new_sel_end + 2; ; pe += 2)
+			if (!ishardspace(sel_pos(pe)) ||
+			    atedge(pe, vc->vc_size_row))
+				break;
+		if (ishardspace(sel_pos(pe)))
+			new_sel_end = pe;
+	}
+	if ((new_sel_start == sel_start) && (new_sel_end == sel_end))
+		return 0; /* no action required */
+
+	sel_start = new_sel_start;
+	sel_end = new_sel_end;
+	/* Allocate a new buffer before freeing the old one ... */
+	bp = kmalloc((sel_end-sel_start)/2+1, GFP_ATOMIC);
+	if (!bp) {
+		printk(KERN_WARNING "selection: kmalloc() failed\n");
+		speakup_clear_selection();
+		return -ENOMEM;
+	}
+	kfree(sel_buffer);
+	sel_buffer = bp;
+
+	obp = bp;
+	for (i = sel_start; i <= sel_end; i += 2) {
+		*bp = sel_pos(i);
+		if (!ishardspace(*bp++))
+			obp = bp;
+		if (!((i + 2) % vc->vc_size_row)) {
+			/* strip trailing blanks from line and add newline,
+			   unless non-space at end of line. */
+			if (obp != bp) {
+				bp = obp;
+				*bp++ = '\r';
+			}
+			obp = bp;
+		}
+	}
+	sel_buffer_lth = bp - sel_buffer;
+	return 0;
+}
+
+/* TODO: move to some helper thread, probably.  That'd fix having to check for
+ * in_atomic().  */
+int speakup_paste_selection(struct tty_struct *tty)
+{
+	struct vc_data *vc = (struct vc_data *) tty->driver_data;
+	int pasted = 0, count;
+	DECLARE_WAITQUEUE(wait, current);
+	add_wait_queue(&vc->paste_wait, &wait);
+	while (sel_buffer && sel_buffer_lth > pasted) {
+		set_current_state(TASK_INTERRUPTIBLE);
+		if (test_bit(TTY_THROTTLED, &tty->flags)) {
+			if (in_atomic())
+				/* can't be performed in an interrupt handler, abort */
+				break;
+			schedule();
+			continue;
+		}
+		count = sel_buffer_lth - pasted;
+		count = min_t(int, count, tty->receive_room);
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,31)
+		tty->ldisc->ops->receive_buf(tty, sel_buffer + pasted, 0, count);
+#elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,27)
+		tty->ldisc.ops->receive_buf(tty, sel_buffer + pasted, 0, count);
+#else
+		tty->ldisc.receive_buf(tty, sel_buffer + pasted, 0, count);
+#endif
+		pasted += count;
+	}
+	remove_wait_queue(&vc->paste_wait, &wait);
+	current->state = TASK_RUNNING;
+	return 0;
+}
+