Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / tty / vt / selection.c
diff --git a/kernel/drivers/tty/vt/selection.c b/kernel/drivers/tty/vt/selection.c
new file mode 100644 (file)
index 0000000..ea27804
--- /dev/null
@@ -0,0 +1,370 @@
+/*
+ * This module exports the functions:
+ *
+ *     'int set_selection(struct tiocl_selection __user *, struct tty_struct *)'
+ *     'void clear_selection(void)'
+ *     'int paste_selection(struct tty_struct *)'
+ *     'int sel_loadlut(char __user *)'
+ *
+ * Now that /dev/vcs exists, most of this can disappear again.
+ */
+
+#include <linux/module.h>
+#include <linux/tty.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#include <asm/uaccess.h>
+
+#include <linux/kbd_kern.h>
+#include <linux/vt_kern.h>
+#include <linux/consolemap.h>
+#include <linux/selection.h>
+#include <linux/tiocl.h>
+#include <linux/console.h>
+#include <linux/tty_flip.h>
+
+/* Don't take this from <ctype.h>: 011-015 on the screen aren't spaces */
+#define isspace(c)     ((c) == ' ')
+
+extern void poke_blanked_console(void);
+
+/* FIXME: all this needs locking */
+/* Variables for selection control. */
+/* Use a dynamic buffer, instead of static (Dec 1994) */
+struct vc_data *sel_cons;              /* must not be deallocated */
+static int use_unicode;
+static volatile int sel_start = -1;    /* cleared by clear_selection */
+static int sel_end;
+static int sel_buffer_lth;
+static char *sel_buffer;
+
+/* clear_selection, highlight and highlight_pointer can be called
+   from interrupt (via scrollback/front) */
+
+/* set reverse video on characters s-e of console with selection. */
+static inline void highlight(const int s, const int e)
+{
+       invert_screen(sel_cons, s, e-s+2, 1);
+}
+
+/* use complementary color to show the pointer */
+static inline void highlight_pointer(const int where)
+{
+       complement_pos(sel_cons, where);
+}
+
+static u16
+sel_pos(int n)
+{
+       return inverse_translate(sel_cons, screen_glyph(sel_cons, n),
+                               use_unicode);
+}
+
+/**
+ *     clear_selection         -       remove current selection
+ *
+ *     Remove the current selection highlight, if any from the console
+ *     holding the selection. The caller must hold the console lock.
+ */
+void clear_selection(void)
+{
+       highlight_pointer(-1); /* hide the pointer */
+       if (sel_start != -1) {
+               highlight(sel_start, sel_end);
+               sel_start = -1;
+       }
+}
+
+/*
+ * User settable table: what characters are to be considered alphabetic?
+ * 256 bits. Locked by the console lock.
+ */
+static u32 inwordLut[8]={
+  0x00000000, /* control chars     */
+  0x03FF0000, /* digits            */
+  0x87FFFFFE, /* uppercase and '_' */
+  0x07FFFFFE, /* lowercase         */
+  0x00000000,
+  0x00000000,
+  0xFF7FFFFF, /* latin-1 accented letters, not multiplication sign */
+  0xFF7FFFFF  /* latin-1 accented letters, not division sign */
+};
+
+static inline int inword(const u16 c) {
+       return c > 0xff || (( inwordLut[c>>5] >> (c & 0x1F) ) & 1);
+}
+
+/**
+ *     set loadlut             -       load the LUT table
+ *     @p: user table
+ *
+ *     Load the LUT table from user space. The caller must hold the console
+ *     lock. Make a temporary copy so a partial update doesn't make a mess.
+ */
+int sel_loadlut(char __user *p)
+{
+       u32 tmplut[8];
+       if (copy_from_user(tmplut, (u32 __user *)(p+4), 32))
+               return -EFAULT;
+       memcpy(inwordLut, tmplut, 32);
+       return 0;
+}
+
+/* does screen address p correspond to character at LH/RH edge of screen? */
+static inline int atedge(const int p, int size_row)
+{
+       return (!(p % size_row) || !((p + 2) % size_row));
+}
+
+/* constrain v such that v <= u */
+static inline unsigned short limit(const unsigned short v, const unsigned short u)
+{
+       return (v > u) ? u : v;
+}
+
+/* stores the char in UTF8 and returns the number of bytes used (1-3) */
+static int store_utf8(u16 c, char *p)
+{
+       if (c < 0x80) {
+               /*  0******* */
+               p[0] = c;
+               return 1;
+       } else if (c < 0x800) {
+               /* 110***** 10****** */
+               p[0] = 0xc0 | (c >> 6);
+               p[1] = 0x80 | (c & 0x3f);
+               return 2;
+       } else {
+               /* 1110**** 10****** 10****** */
+               p[0] = 0xe0 | (c >> 12);
+               p[1] = 0x80 | ((c >> 6) & 0x3f);
+               p[2] = 0x80 | (c & 0x3f);
+               return 3;
+       }
+}
+
+/**
+ *     set_selection           -       set the current selection.
+ *     @sel: user selection info
+ *     @tty: the console tty
+ *
+ *     Invoked by the ioctl handle for the vt layer.
+ *
+ *     The entire selection process is managed under the console_lock. It's
+ *      a lot under the lock but its hardly a performance path
+ */
+int set_selection(const struct tiocl_selection __user *sel, struct tty_struct *tty)
+{
+       struct vc_data *vc = vc_cons[fg_console].d;
+       int sel_mode, new_sel_start, new_sel_end, spc;
+       char *bp, *obp;
+       int i, ps, pe, multiplier;
+       u16 c;
+       int mode;
+
+       poke_blanked_console();
+
+       { unsigned short xs, ys, xe, ye;
+
+         if (!access_ok(VERIFY_READ, sel, sizeof(*sel)))
+               return -EFAULT;
+         __get_user(xs, &sel->xs);
+         __get_user(ys, &sel->ys);
+         __get_user(xe, &sel->xe);
+         __get_user(ye, &sel->ye);
+         __get_user(sel_mode, &sel->sel_mode);
+         xs--; ys--; xe--; ye--;
+         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 (sel_mode == TIOCL_SELCLEAR) {
+             /* useful for screendump without selection highlights */
+             clear_selection();
+             return 0;
+         }
+
+         if (mouse_reporting() && (sel_mode & TIOCL_SELMOUSEREPORT)) {
+             mouse_report(tty, sel_mode & TIOCL_SELBUTTONMASK, xs, ys);
+             return 0;
+         }
+        }
+
+       if (ps > pe)    /* make sel_start <= sel_end */
+       {
+               int tmp = ps;
+               ps = pe;
+               pe = tmp;
+       }
+
+       if (sel_cons != vc_cons[fg_console].d) {
+               clear_selection();
+               sel_cons = vc_cons[fg_console].d;
+       }
+       mode = vt_do_kdgkbmode(fg_console);
+       if (mode == K_UNICODE)
+               use_unicode = 1;
+       else
+               use_unicode = 0;
+
+       switch (sel_mode)
+       {
+               case TIOCL_SELCHAR:     /* character-by-character selection */
+                       new_sel_start = ps;
+                       new_sel_end = pe;
+                       break;
+               case TIOCL_SELWORD:     /* word-by-word selection */
+                       spc = isspace(sel_pos(ps));
+                       for (new_sel_start = ps; ; ps -= 2)
+                       {
+                               if ((spc && !isspace(sel_pos(ps))) ||
+                                   (!spc && !inword(sel_pos(ps))))
+                                       break;
+                               new_sel_start = ps;
+                               if (!(ps % vc->vc_size_row))
+                                       break;
+                       }
+                       spc = isspace(sel_pos(pe));
+                       for (new_sel_end = pe; ; pe += 2)
+                       {
+                               if ((spc && !isspace(sel_pos(pe))) ||
+                                   (!spc && !inword(sel_pos(pe))))
+                                       break;
+                               new_sel_end = pe;
+                               if (!((pe + 2) % vc->vc_size_row))
+                                       break;
+                       }
+                       break;
+               case TIOCL_SELLINE:     /* line-by-line selection */
+                       new_sel_start = ps - ps % vc->vc_size_row;
+                       new_sel_end = pe + vc->vc_size_row
+                                   - pe % vc->vc_size_row - 2;
+                       break;
+               case TIOCL_SELPOINTER:
+                       highlight_pointer(pe);
+                       return 0;
+               default:
+                       return -EINVAL;
+       }
+
+       /* remove the pointer */
+       highlight_pointer(-1);
+
+       /* select to end of line if on trailing space */
+       if (new_sel_end > new_sel_start &&
+               !atedge(new_sel_end, vc->vc_size_row) &&
+               isspace(sel_pos(new_sel_end))) {
+               for (pe = new_sel_end + 2; ; pe += 2)
+                       if (!isspace(sel_pos(pe)) ||
+                           atedge(pe, vc->vc_size_row))
+                               break;
+               if (isspace(sel_pos(pe)))
+                       new_sel_end = pe;
+       }
+       if (sel_start == -1)    /* no current selection */
+               highlight(new_sel_start, new_sel_end);
+       else if (new_sel_start == sel_start)
+       {
+               if (new_sel_end == sel_end)     /* no action required */
+                       return 0;
+               else if (new_sel_end > sel_end) /* extend to right */
+                       highlight(sel_end + 2, new_sel_end);
+               else                            /* contract from right */
+                       highlight(new_sel_end + 2, sel_end);
+       }
+       else if (new_sel_end == sel_end)
+       {
+               if (new_sel_start < sel_start)  /* extend to left */
+                       highlight(new_sel_start, sel_start - 2);
+               else                            /* contract from left */
+                       highlight(sel_start, new_sel_start - 2);
+       }
+       else    /* some other case; start selection from scratch */
+       {
+               clear_selection();
+               highlight(new_sel_start, new_sel_end);
+       }
+       sel_start = new_sel_start;
+       sel_end = new_sel_end;
+
+       /* Allocate a new buffer before freeing the old one ... */
+       multiplier = use_unicode ? 3 : 1;  /* chars can take up to 3 bytes */
+       bp = kmalloc(((sel_end-sel_start)/2+1)*multiplier, GFP_KERNEL);
+       if (!bp) {
+               printk(KERN_WARNING "selection: kmalloc() failed\n");
+               clear_selection();
+               return -ENOMEM;
+       }
+       kfree(sel_buffer);
+       sel_buffer = bp;
+
+       obp = bp;
+       for (i = sel_start; i <= sel_end; i += 2) {
+               c = sel_pos(i);
+               if (use_unicode)
+                       bp += store_utf8(c, bp);
+               else
+                       *bp++ = c;
+               if (!isspace(c))
+                       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;
+}
+
+/* Insert the contents of the selection buffer into the
+ * queue of the tty associated with the current console.
+ * Invoked by ioctl().
+ *
+ * Locking: called without locks. Calls the ldisc wrongly with
+ * unsafe methods,
+ */
+int paste_selection(struct tty_struct *tty)
+{
+       struct vc_data *vc = tty->driver_data;
+       int     pasted = 0;
+       unsigned int count;
+       struct  tty_ldisc *ld;
+       DECLARE_WAITQUEUE(wait, current);
+
+       console_lock();
+       poke_blanked_console();
+       console_unlock();
+
+       ld = tty_ldisc_ref_wait(tty);
+       tty_buffer_lock_exclusive(&vc->port);
+
+       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)) {
+                       schedule();
+                       continue;
+               }
+               count = sel_buffer_lth - pasted;
+               count = tty_ldisc_receive_buf(ld, sel_buffer + pasted, NULL,
+                                             count);
+               pasted += count;
+       }
+       remove_wait_queue(&vc->paste_wait, &wait);
+       __set_current_state(TASK_RUNNING);
+
+       tty_buffer_unlock_exclusive(&vc->port);
+       tty_ldisc_deref(ld);
+       return 0;
+}