src/w32select.c

   1 /* Selection processing for Emacs on the Microsoft W32 API.
   2    Copyright (C) 1993, 1994 Free Software Foundation.
   3
   4 This file is part of GNU Emacs.
   5
   6 GNU Emacs is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Emacs is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Emacs; see the file COPYING.  If not, write to
  18 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21 /* Written by Kevin Gallo */
  22
  23 #include <config.h>
  24 #include "lisp.h"
  25 #include "w32term.h"    /* for all of the w32 includes */
  26 #include "dispextern.h" /* frame.h seems to want this */
  27 #include "keyboard.h"
  28 #include "frame.h"      /* Need this to get the X window of selected_frame */
  29 #include "blockinput.h"
  30 #include "buffer.h"
  31 #include "charset.h"
  32 #include "coding.h"
  33 #include "composite.h"
  34
  35 Lisp_Object QCLIPBOARD;
  36
  37 /* Coding system for communicating with other Windows programs via the
  38    clipboard.  */
  39 static Lisp_Object Vselection_coding_system;
  40
  41 /* Coding system for the next communicating with other Windows programs.  */
  42 static Lisp_Object Vnext_selection_coding_system;
  43
  44 /* The last text we put into the clipboard.  This is used to prevent
  45    passing back our own text from the clipboard, instead of using the
  46    kill ring.  The former is undesirable because the clipboard data
  47    could be MULEtilated by inappropriately chosen
  48    (next-)selection-coding-system.  For this reason, we must store the
  49    text *after* it was encoded/Unix-to-DOS-converted.  */
  50 static unsigned char *last_clipboard_text = NULL;
  51 static size_t clipboard_storage_size = 0;
  52
  53 #if 0
  54 DEFUN ("w32-open-clipboard", Fw32_open_clipboard, Sw32_open_clipboard, 0, 1, 0,
  55        doc: /* This opens the clipboard with the given frame pointer.  */)
  56      (frame)
  57      Lisp_Object frame;
  58 {
  59   BOOL ok = FALSE;
  60
  61   if (!NILP (frame))
  62     CHECK_LIVE_FRAME (frame);
  63
  64   BLOCK_INPUT;
  65
  66   ok = OpenClipboard ((!NILP (frame) && FRAME_W32_P (XFRAME (frame))) ? FRAME_W32_WINDOW (XFRAME (frame)) : NULL);
  67
  68   UNBLOCK_INPUT;
  69
  70   return (ok ? frame : Qnil);
  71 }
  72
  73 DEFUN ("w32-empty-clipboard", Fw32_empty_clipboard,
  74        Sw32_empty_clipboard, 0, 0, 0,
  75        doc: /* Empty the clipboard.
  76 Assigns ownership of the clipboard to the window which opened it.  */)
  77      ()
  78 {
  79   BOOL ok = FALSE;
  80
  81   BLOCK_INPUT;
  82
  83   ok = EmptyClipboard ();
  84
  85   UNBLOCK_INPUT;
  86
  87   return (ok ? Qt : Qnil);
  88 }
  89
  90 DEFUN ("w32-close-clipboard", Fw32_close_clipboard,
  91        Sw32_close_clipboard, 0, 0, 0,
  92        doc: /* Close the clipboard.  */)
  93      ()
  94 {
  95   BOOL ok = FALSE;
  96
  97   BLOCK_INPUT;
  98
  99   ok = CloseClipboard ();
 100
 101   UNBLOCK_INPUT;
 102
 103   return (ok ? Qt : Qnil);
 104 }
 105
 106 #endif
 107
 108 DEFUN ("w32-set-clipboard-data", Fw32_set_clipboard_data,
 109        Sw32_set_clipboard_data, 1, 2, 0,
 110        doc: /* This sets the clipboard data to the given text.  */)
 111     (string, frame)
 112     Lisp_Object string, frame;
 113 {
 114   BOOL ok = TRUE;
 115   HANDLE htext;
 116   int nbytes;
 117   int truelen, nlines = 0;
 118   unsigned char *src;
 119   unsigned char *dst;
 120
 121   CHECK_STRING (string);
 122
 123   if (!NILP (frame))
 124     CHECK_LIVE_FRAME (frame);
 125
 126   BLOCK_INPUT;
 127
 128   nbytes = SBYTES (string) + 1;
 129   src = SDATA (string);
 130   dst = src;
 131
 132   /* We need to know how many lines there are, since we need CRLF line
 133      termination for compatibility with other Windows Programs.
 134      avoid using strchr because it recomputes the length every time */
 135   while ((dst = memchr (dst, '\n', nbytes - (dst - src))) != NULL)
 136     {
 137       nlines++;
 138       dst++;
 139     }
 140
 141   {
 142     /* Since we are now handling multilingual text, we must consider
 143        encoding text for the clipboard.  */
 144     int charset_info = find_charset_in_text (src, SCHARS (string),
 145                                              nbytes, NULL, Qnil);
 146
 147     if (charset_info == 0)
 148       {
 149         /* No multibyte character in OBJ.  We need not encode it.  */
 150
 151         /* Need to know final size after CR chars are inserted (the
 152            standard CF_TEXT clipboard format uses CRLF line endings,
 153            while Emacs uses just LF internally).  */
 154
 155         truelen = nbytes + nlines;
 156
 157         if ((htext = GlobalAlloc (GMEM_MOVEABLE | GMEM_DDESHARE, truelen)) == NULL)
 158           goto error;
 159
 160         if ((dst = (unsigned char *) GlobalLock (htext)) == NULL)
 161           goto error;
 162
 163         /* convert to CRLF line endings expected by clipboard */
 164         while (1)
 165           {
 166             unsigned char *next;
 167             /* copy next line or remaining bytes including '\0' */
 168             next = _memccpy (dst, src, '\n', nbytes);
 169             if (next)
 170               {
 171                 /* copied one line ending with '\n' */
 172                 int copied = next - dst;
 173                 nbytes -= copied;
 174                 src += copied;
 175                 /* insert '\r' before '\n' */
 176                 next[-1] = '\r';
 177                 next[0] = '\n';
 178                 dst = next + 1;
 179               }
 180             else
 181               /* copied remaining partial line -> now finished */
 182               break;
 183           }
 184
 185         GlobalUnlock (htext);
 186
 187         Vlast_coding_system_used = Qraw_text;
 188       }
 189     else
 190       {
 191         /* We must encode contents of OBJ to the selection coding
 192            system. */
 193         int bufsize;
 194         struct coding_system coding;
 195         HANDLE htext2;
 196
 197         if (NILP (Vnext_selection_coding_system))
 198           Vnext_selection_coding_system = Vselection_coding_system;
 199         setup_coding_system
 200           (Fcheck_coding_system (Vnext_selection_coding_system), &coding);
 201         if (SYMBOLP (coding.pre_write_conversion)
 202             && !NILP (Ffboundp (coding.pre_write_conversion)))
 203           {
 204             string = run_pre_post_conversion_on_str (string, &coding, 1);
 205             src = SDATA (string);
 206             nbytes = SBYTES (string);
 207           }
 208         coding.src_multibyte = 1;
 209         coding.dst_multibyte = 0;
 210         Vnext_selection_coding_system = Qnil;
 211         coding.mode |= CODING_MODE_LAST_BLOCK;
 212         bufsize = encoding_buffer_size (&coding, nbytes);
 213         if ((htext = GlobalAlloc (GMEM_MOVEABLE | GMEM_DDESHARE, bufsize)) == NULL)
 214           goto error;
 215         if ((dst = (unsigned char *) GlobalLock (htext)) == NULL)
 216           goto error;
 217         encode_coding (&coding, src, dst, nbytes, bufsize);
 218         Vlast_coding_system_used = coding.symbol;
 219
 220         /* Stash away the data we are about to put into the clipboard, so we
 221            could later check inside Fw32_get_clipboard_data whether
 222            the clipboard still holds our data.  */
 223         if (clipboard_storage_size < coding.produced)
 224           {
 225             clipboard_storage_size = coding.produced + 100;
 226             last_clipboard_text = (char *) xrealloc (last_clipboard_text,
 227                                                      clipboard_storage_size);
 228           }
 229         if (last_clipboard_text)
 230           memcpy (last_clipboard_text, dst, coding.produced);
 231
 232         GlobalUnlock (htext);
 233
 234         /* Shrink data block to actual size.  */
 235         htext2 = GlobalReAlloc (htext, coding.produced,
 236                                 GMEM_MOVEABLE | GMEM_DDESHARE);
 237         if (htext2 != NULL) htext = htext2;
 238       }
 239   }
 240
 241   if (!OpenClipboard ((!NILP (frame) && FRAME_W32_P (XFRAME (frame))) ? FRAME_W32_WINDOW (XFRAME (frame)) : NULL))
 242     goto error;
 243
 244   ok = EmptyClipboard () && SetClipboardData (CF_TEXT, htext);
 245
 246   CloseClipboard ();
 247
 248   if (ok) goto done;
 249
 250  error:
 251
 252   ok = FALSE;
 253   if (htext) GlobalFree (htext);
 254   if (last_clipboard_text)
 255     *last_clipboard_text = '\0';
 256
 257  done:
 258   UNBLOCK_INPUT;
 259
 260   return (ok ? string : Qnil);
 261 }
 262
 263 DEFUN ("w32-get-clipboard-data", Fw32_get_clipboard_data,
 264        Sw32_get_clipboard_data, 0, 1, 0,
 265        doc: /* This gets the clipboard data in text format.  */)
 266      (frame)
 267      Lisp_Object frame;
 268 {
 269   HANDLE htext;
 270   Lisp_Object ret = Qnil;
 271
 272   if (!NILP (frame))
 273     CHECK_LIVE_FRAME (frame);
 274
 275   BLOCK_INPUT;
 276
 277   if (!OpenClipboard ((!NILP (frame) && FRAME_W32_P (XFRAME (frame))) ? FRAME_W32_WINDOW (XFRAME (frame)) : NULL))
 278     goto done;
 279
 280   if ((htext = GetClipboardData (CF_TEXT)) == NULL)
 281     goto closeclip;
 282
 283   {
 284     unsigned char *src;
 285     unsigned char *dst;
 286     int nbytes;
 287     int truelen;
 288     int require_decoding = 0;
 289
 290     if ((src = (unsigned char *) GlobalLock (htext)) == NULL)
 291       goto closeclip;
 292
 293     nbytes = strlen (src);
 294
 295     /* If the text in clipboard is identical to what we put there
 296        last time w32_set_clipboard_data was called, pretend there's no
 297        data in the clipboard.  This is so we don't pass our own text
 298        from the clipboard (which might be troublesome if the killed
 299        text includes null characters).  */
 300     if (last_clipboard_text
 301         && clipboard_storage_size >= nbytes
 302         && memcmp(last_clipboard_text, src, nbytes) == 0)
 303       goto closeclip;
 304
 305     {
 306       /* If the clipboard data contains any non-ascii code, we
 307          need to decode it.  */
 308       int i;
 309
 310       for (i = 0; i < nbytes; i++)
 311         {
 312           if (src[i] >= 0x80)
 313             {
 314               require_decoding = 1;
 315               break;
 316             }
 317         }
 318     }
 319
 320     if (require_decoding)
 321       {
 322         int bufsize;
 323         unsigned char *buf;
 324         struct coding_system coding;
 325
 326         if (NILP (Vnext_selection_coding_system))
 327           Vnext_selection_coding_system = Vselection_coding_system;
 328         setup_coding_system
 329           (Fcheck_coding_system (Vnext_selection_coding_system), &coding);
 330         coding.src_multibyte = 0;
 331         coding.dst_multibyte = 1;
 332         Vnext_selection_coding_system = Qnil;
 333         coding.mode |= CODING_MODE_LAST_BLOCK;
 334         /* We explicitely disable composition handling because
 335            selection data should not contain any composition
 336            sequence.  */
 337         coding.composing = COMPOSITION_DISABLED;
 338         bufsize = decoding_buffer_size (&coding, nbytes);
 339         buf = (unsigned char *) xmalloc (bufsize);
 340         decode_coding (&coding, src, buf, nbytes, bufsize);
 341         Vlast_coding_system_used = coding.symbol;
 342         ret = make_string_from_bytes ((char *) buf,
 343                                       coding.produced_char, coding.produced);
 344         xfree (buf);
 345         if (SYMBOLP (coding.post_read_conversion)
 346             && !NILP (Ffboundp (coding.post_read_conversion)))
 347           ret = run_pre_post_conversion_on_str (ret, &coding, 0);
 348       }
 349     else
 350       {
 351         /* Need to know final size after CR chars are removed because we
 352            can't change the string size manually, and doing an extra
 353            copy is silly.  Note that we only remove CR when it appears
 354            as part of CRLF.  */
 355
 356         truelen = nbytes;
 357         dst = src;
 358         /* avoid using strchr because it recomputes the length everytime */
 359         while ((dst = memchr (dst, '\r', nbytes - (dst - src))) != NULL)
 360           {
 361             if (dst[1] == '\n') /* safe because of trailing '\0' */
 362               truelen--;
 363             dst++;
 364           }
 365
 366         ret = make_uninit_string (truelen);
 367
 368         /* Convert CRLF line endings (the standard CF_TEXT clipboard
 369            format) to LF endings as used internally by Emacs.  */
 370
 371         dst = SDATA (ret);
 372         while (1)
 373           {
 374             unsigned char *next;
 375             /* copy next line or remaining bytes excluding '\0' */
 376             next = _memccpy (dst, src, '\r', nbytes);
 377             if (next)
 378               {
 379                 /* copied one line ending with '\r' */
 380                 int copied = next - dst;
 381                 nbytes -= copied;
 382                 dst += copied;
 383                 src += copied;
 384                 if (*src == '\n')
 385                   dst--;        /* overwrite '\r' with '\n' */
 386               }
 387             else
 388               /* copied remaining partial line -> now finished */
 389               break;
 390           }
 391
 392         Vlast_coding_system_used = Qraw_text;
 393       }
 394
 395     GlobalUnlock (htext);
 396   }
 397
 398  closeclip:
 399   CloseClipboard ();
 400
 401  done:
 402   UNBLOCK_INPUT;
 403
 404   return (ret);
 405 }
 406
 407 /* Support checking for a clipboard selection. */
 408
 409 DEFUN ("x-selection-exists-p", Fx_selection_exists_p, Sx_selection_exists_p,
 410        0, 1, 0,
 411        doc: /* Whether there is an owner for the given X Selection.
 412 The arg should be the name of the selection in question, typically one of
 413 the symbols `PRIMARY', `SECONDARY', or `CLIPBOARD'.
 414 \(Those are literal upper-case symbol names, since that's what X expects.)
 415 For convenience, the symbol nil is the same as `PRIMARY',
 416 and t is the same as `SECONDARY'.  */)
 417   (selection)
 418      Lisp_Object selection;
 419 {
 420   CHECK_SYMBOL (selection);
 421
 422   /* Return nil for PRIMARY and SECONDARY selections; for CLIPBOARD, check
 423      if the clipboard currently has valid text format contents. */
 424
 425   if (EQ (selection, QCLIPBOARD))
 426     {
 427       Lisp_Object val = Qnil;
 428
 429       if (OpenClipboard (NULL))
 430         {
 431           int format = 0;
 432           while (format = EnumClipboardFormats (format))
 433             if (format == CF_TEXT)
 434               {
 435                 val = Qt;
 436                 break;
 437               }
 438           CloseClipboard ();
 439         }
 440       return val;
 441     }
 442   return Qnil;
 443 }
 444
 445 void
 446 syms_of_w32select ()
 447 {
 448 #if 0
 449   defsubr (&Sw32_open_clipboard);
 450   defsubr (&Sw32_empty_clipboard);
 451   defsubr (&Sw32_close_clipboard);
 452 #endif
 453   defsubr (&Sw32_set_clipboard_data);
 454   defsubr (&Sw32_get_clipboard_data);
 455   defsubr (&Sx_selection_exists_p);
 456
 457   DEFVAR_LISP ("selection-coding-system", &Vselection_coding_system,
 458                doc: /* Coding system for communicating with other programs.
 459 When sending or receiving text via cut_buffer, selection, and clipboard,
 460 the text is encoded or decoded by this coding system.  */);
 461   Vselection_coding_system=intern ("iso-latin-1-dos");
 462
 463   DEFVAR_LISP ("next-selection-coding-system", &Vnext_selection_coding_system,
 464                doc: /* Coding system for the next communication with other programs.
 465 Usually, `selection-coding-system' is used for communicating with
 466 other programs.   But, if this variable is set, it is used for the
 467 next communication only.   After the communication, this variable is
 468 set to nil.  */);
 469   Vnext_selection_coding_system = Qnil;
 470
 471   QCLIPBOARD = intern ("CLIPBOARD");    staticpro (&QCLIPBOARD);
 472 }