src/gui.h

   1 /* vi:set ts=8 sts=4 sw=4:
   2  *
   3  * VIM - Vi IMproved            by Bram Moolenaar
   4  *                              Motif support by Robert Webb
   5  *
   6  * Do ":help uganda"  in Vim to read copying and usage conditions.
   7  * Do ":help credits" in Vim to see a list of people who contributed.
   8  */
   9
  10 #ifdef FEAT_GUI_MOTIF
  11 # include <Xm/Xm.h>
  12 #endif
  13
  14 #ifdef FEAT_GUI_ATHENA
  15 # include <X11/Intrinsic.h>
  16 # include <X11/StringDefs.h>
  17 #endif
  18
  19 #ifdef FEAT_BEVAL
  20 # include "gui_beval.h"
  21 #endif
  22
  23 #ifdef FEAT_GUI_GTK
  24 # ifdef VMS /* undef MIN and MAX because Intrinsic.h redefines them anyway */
  25 #  ifdef MAX
  26 #   undef MAX
  27 #  endif
  28 #  ifdef MIN
  29 #   undef MIN
  30 #  endif
  31 # endif
  32 # include <X11/Intrinsic.h>
  33 # include <gtk/gtk.h>
  34 #endif
  35
  36 #ifdef FEAT_GUI_MAC
  37 # include <Types.h>
  38 /*# include <Memory.h>*/
  39 # include <Quickdraw.h>
  40 # include <Fonts.h>
  41 # include <Events.h>
  42 # include <Menus.h>
  43 # if !(defined (TARGET_API_MAC_CARBON) && (TARGET_API_MAC_CARBON))
  44 #   include <Windows.h>
  45 # endif
  46 # include <Controls.h>
  47 /*# include <TextEdit.h>*/
  48 # include <Dialogs.h>
  49 # include <OSUtils.h>
  50 /*
  51 # include <ToolUtils.h>
  52 # include <SegLoad.h>*/
  53 #endif
  54
  55 #ifdef RISCOS
  56 # include "gui_riscos.h"
  57 #endif
  58
  59 #ifdef FEAT_GUI_PHOTON
  60 # include <Ph.h>
  61 # include <Pt.h>
  62 # include "photon/PxProto.h"
  63 #endif
  64
  65 /*
  66  * On some systems, when we compile with the GUI, we always use it.  On Mac
  67  * there is no terminal version, and on Windows we can't figure out how to
  68  * fork one off with :gui.
  69  */
  70 #if defined(FEAT_GUI_MSWIN) || (defined(FEAT_GUI_MAC) && !defined(MACOS_X_UNIX))
  71 # define ALWAYS_USE_GUI
  72 #endif
  73
  74 #if defined(FEAT_GUI_MSWIN) || defined(FEAT_GUI_MAC) || defined(HAVE_GTK2)
  75 # define USE_ON_FLY_SCROLL
  76 #endif
  77
  78 /*
  79  * GUIs that support dropping files on a running Vim.
  80  */
  81 #if defined(FEAT_GUI_MSWIN) || defined(FEAT_GUI_MAC) \
  82         || defined(FEAT_GUI_GTK)
  83 # define HAVE_DROP_FILE
  84 #endif
  85
  86 /*
  87  * This define makes menus always use a fontset.
  88  * We're not sure if this code always works, thus it can be disabled.
  89  */
  90 #ifdef FEAT_XFONTSET
  91 # define FONTSET_ALWAYS
  92 #endif
  93
  94 /*
  95  * These macros convert between character row/column and pixel coordinates.
  96  * TEXT_X   - Convert character column into X pixel coord for drawing strings.
  97  * TEXT_Y   - Convert character row into Y pixel coord for drawing strings.
  98  * FILL_X   - Convert character column into X pixel coord for filling the area
  99  *              under the character.
 100  * FILL_Y   - Convert character row into Y pixel coord for filling the area
 101  *              under the character.
 102  * X_2_COL  - Convert X pixel coord into character column.
 103  * Y_2_ROW  - Convert Y pixel coord into character row.
 104  */
 105 #ifdef FEAT_GUI_W32
 106 # define TEXT_X(col)    ((col) * gui.char_width)
 107 # define TEXT_Y(row)    ((row) * gui.char_height + gui.char_ascent)
 108 # define FILL_X(col)    ((col) * gui.char_width)
 109 # define FILL_Y(row)    ((row) * gui.char_height)
 110 # define X_2_COL(x)     ((x) / gui.char_width)
 111 # define Y_2_ROW(y)     ((y) / gui.char_height)
 112 #else
 113 # define TEXT_X(col)    ((col) * gui.char_width  + gui.border_offset)
 114 # define FILL_X(col)    ((col) * gui.char_width  + gui.border_offset)
 115 # define X_2_COL(x)     (((x) - gui.border_offset) / gui.char_width)
 116 # define TEXT_Y(row)    ((row) * gui.char_height + gui.char_ascent \
 117                                                         + gui.border_offset)
 118 # define FILL_Y(row)    ((row) * gui.char_height + gui.border_offset)
 119 # define Y_2_ROW(y)     (((y) - gui.border_offset) / gui.char_height)
 120 #endif
 121
 122 /* Indices for arrays of scrollbars */
 123 #define SBAR_NONE           -1
 124 #define SBAR_LEFT           0
 125 #define SBAR_RIGHT          1
 126 #define SBAR_BOTTOM         2
 127
 128 /* Orientations for scrollbars */
 129 #define SBAR_VERT           0
 130 #define SBAR_HORIZ          1
 131
 132 /* Default size of scrollbar */
 133 #define SB_DEFAULT_WIDTH    16
 134
 135 /* Default height of the menu bar */
 136 #define MENU_DEFAULT_HEIGHT 1           /* figure it out at runtime */
 137
 138 /* Flags for gui_mch_outstr_nowrap() */
 139 #define GUI_MON_WRAP_CURSOR     0x01    /* wrap cursor at end of line */
 140 #define GUI_MON_INVERT          0x02    /* invert the characters */
 141 #define GUI_MON_IS_CURSOR       0x04    /* drawing cursor */
 142 #define GUI_MON_TRS_CURSOR      0x08    /* drawing transparent cursor */
 143 #define GUI_MON_NOCLEAR         0x10    /* don't clear selection */
 144
 145 /* Flags for gui_mch_draw_string() */
 146 #define DRAW_TRANSP             0x01    /* draw with transparant bg */
 147 #define DRAW_BOLD               0x02    /* draw bold text */
 148 #define DRAW_UNDERL             0x04    /* draw underline text */
 149 #define DRAW_UNDERC             0x08    /* draw undercurl text */
 150 #if defined(RISCOS) || defined(HAVE_GTK2)
 151 # define DRAW_ITALIC            0x10    /* draw italic text */
 152 #endif
 153 #define DRAW_CURSOR             0x20    /* drawing block cursor (win32) */
 154
 155 /* For our own tearoff menu item */
 156 #define TEAR_STRING             "-->Detach"
 157 #define TEAR_LEN                (9)     /* length of above string */
 158
 159 /* for the toolbar */
 160 #ifdef FEAT_GUI_W16
 161 # define TOOLBAR_BUTTON_HEIGHT  15
 162 # define TOOLBAR_BUTTON_WIDTH   16
 163 #else
 164 # define TOOLBAR_BUTTON_HEIGHT  18
 165 # define TOOLBAR_BUTTON_WIDTH   18
 166 #endif
 167 #define TOOLBAR_BORDER_HEIGHT   12  /* room above+below buttons for MSWindows */
 168
 169 #ifdef FEAT_GUI_MSWIN
 170 # define TABLINE_HEIGHT 22
 171 #endif
 172 #ifdef FEAT_GUI_MOTIF
 173 # define TABLINE_HEIGHT 30
 174 #endif
 175
 176 #if defined(NO_CONSOLE) || defined(FEAT_GUI_GTK) || defined(FEAT_GUI_X11)
 177 # define NO_CONSOLE_INPUT       /* use no_console_input() to check if there
 178                                    is no console input possible */
 179 #endif
 180
 181 typedef struct GuiScrollbar
 182 {
 183     long        ident;          /* Unique identifier for each scrollbar */
 184     win_T       *wp;            /* Scrollbar's window, NULL for bottom */
 185     int         type;           /* one of SBAR_{LEFT,RIGHT,BOTTOM} */
 186     long        value;          /* Represents top line number visible */
 187 #ifdef FEAT_GUI_ATHENA
 188     int         pixval;         /* pixel count of value */
 189 #endif
 190     long        size;           /* Size of scrollbar thumb */
 191     long        max;            /* Number of lines in buffer */
 192
 193     /* Values measured in characters: */
 194     int         top;            /* Top of scroll bar (chars from row 0) */
 195     int         height;         /* Current height of scroll bar in rows */
 196 #ifdef FEAT_VERTSPLIT
 197     int         width;          /* Current width of scroll bar in cols */
 198 #endif
 199     int         status_height;  /* Height of status line */
 200 #ifdef FEAT_GUI_X11
 201     Widget      id;             /* Id of real scroll bar */
 202 #endif
 203 #ifdef FEAT_GUI_GTK
 204     GtkWidget *id;              /* Id of real scroll bar */
 205     unsigned long handler_id;   /* Id of "value_changed" signal handler */
 206 #endif
 207
 208 #ifdef FEAT_GUI_MSWIN
 209     HWND        id;             /* Id of real scroll bar */
 210     int         scroll_shift;   /* The scrollbar stuff can handle only up to
 211                                    32767 lines.  When the file is longer,
 212                                    scroll_shift is set to the number of shifts
 213                                    to reduce the count.  */
 214 #endif
 215 #ifdef FEAT_GUI_MAC
 216     ControlHandle id;           /* A handle to the scrollbar */
 217 #endif
 218 #ifdef RISCOS
 219     int         id;             /* Window handle of scrollbar window */
 220 #endif
 221 #ifdef FEAT_GUI_PHOTON
 222     PtWidget_t  *id;
 223 #endif
 224 } scrollbar_T;
 225
 226 typedef long        guicolor_T; /* handle for a GUI color; for X11 this should
 227                                    be "Pixel", but that's an unsigned and we
 228                                    need a signed value */
 229 #define INVALCOLOR (guicolor_T)-11111   /* number for invalid color; on 32 bit
 230                                    displays there is a tiny chance this is an
 231                                    actual color */
 232
 233 #ifdef FEAT_GUI_GTK
 234 # ifdef HAVE_GTK2
 235   typedef PangoFontDescription  *GuiFont;       /* handle for a GUI font */
 236   typedef PangoFontDescription  *GuiFontset;    /* handle for a GUI fontset */
 237 # else
 238   typedef GdkFont       *GuiFont;       /* handle for a GUI font */
 239   typedef GdkFont       *GuiFontset;    /* handle for a GUI fontset */
 240 # endif
 241 # define NOFONT         (GuiFont)NULL
 242 # define NOFONTSET      (GuiFontset)NULL
 243 #else
 244 # ifdef FEAT_GUI_PHOTON
 245   typedef char          *GuiFont;
 246   typedef char          *GuiFontset;
 247 #  define NOFONT        (GuiFont)NULL
 248 #  define NOFONTSET     (GuiFontset)NULL
 249 # else
 250 #  ifdef FEAT_GUI_X11
 251   typedef XFontStruct   *GuiFont;       /* handle for a GUI font */
 252   typedef XFontSet      GuiFontset;     /* handle for a GUI fontset */
 253 #   define NOFONT       (GuiFont)0
 254 #   define NOFONTSET    (GuiFontset)0
 255 #  else
 256   typedef long_u        GuiFont;        /* handle for a GUI font */
 257   typedef long_u        GuiFontset;     /* handle for a GUI fontset */
 258 #   define NOFONT       (GuiFont)0
 259 #   define NOFONTSET    (GuiFontset)0
 260 #  endif
 261 # endif
 262 #endif
 263
 264 typedef struct Gui
 265 {
 266     int         in_focus;           /* Vim has input focus */
 267     int         in_use;             /* Is the GUI being used? */
 268     int         starting;           /* GUI will start in a little while */
 269     int         shell_created;      /* Has the shell been created yet? */
 270     int         dying;              /* Is vim dying? Then output to terminal */
 271     int         dofork;             /* Use fork() when GUI is starting */
 272     int         dragged_sb;         /* Which scrollbar being dragged, if any? */
 273     win_T       *dragged_wp;        /* Which WIN's sb being dragged, if any? */
 274     int         pointer_hidden;     /* Is the mouse pointer hidden? */
 275     int         col;                /* Current cursor column in GUI display */
 276     int         row;                /* Current cursor row in GUI display */
 277     int         cursor_col;         /* Physical cursor column in GUI display */
 278     int         cursor_row;         /* Physical cursor row in GUI display */
 279     char        cursor_is_valid;    /* There is a cursor at cursor_row/col */
 280     int         num_cols;           /* Number of columns */
 281     int         num_rows;           /* Number of rows */
 282     int         scroll_region_top;  /* Top (first) line of scroll region */
 283     int         scroll_region_bot;  /* Bottom (last) line of scroll region */
 284     int         scroll_region_left;  /* Left (first) column of scroll region */
 285     int         scroll_region_right;  /* Right (last) col. of scroll region */
 286     int         highlight_mask;     /* Highlight attribute mask */
 287     int         scrollbar_width;    /* Width of vertical scrollbars */
 288     int         scrollbar_height;   /* Height of horizontal scrollbar */
 289     int         left_sbar_x;        /* Calculated x coord for left scrollbar */
 290     int         right_sbar_x;       /* Calculated x coord for right scrollbar */
 291
 292 #ifdef FEAT_MENU
 293 # ifndef FEAT_GUI_GTK
 294     int         menu_height;        /* Height of the menu bar */
 295     int         menu_width;         /* Width of the menu bar */
 296 # endif
 297     char        menu_is_active;     /* TRUE if menu is present */
 298 # ifdef FEAT_GUI_ATHENA
 299     char        menu_height_fixed;  /* TRUE if menu height fixed */
 300 # endif
 301 #endif
 302
 303     scrollbar_T bottom_sbar;        /* Bottom scrollbar */
 304     int         which_scrollbars[3];/* Which scrollbar boxes are active? */
 305     int         prev_wrap;          /* For updating the horizontal scrollbar */
 306     int         char_width;         /* Width of char cell in pixels */
 307     int         char_height;        /* Height of char cell in pixels, includes
 308                                        'linespace' */
 309     int         char_ascent;        /* Ascent of char in pixels */
 310     int         border_width;       /* Width of our border around text area */
 311     int         border_offset;      /* Total pixel offset for all borders */
 312
 313     GuiFont     norm_font;          /* Normal font */
 314 #ifndef HAVE_GTK2
 315     GuiFont     bold_font;          /* Bold font */
 316     GuiFont     ital_font;          /* Italic font */
 317     GuiFont     boldital_font;      /* Bold-Italic font */
 318 #else
 319     int         font_can_bold;      /* Whether norm_font supports bold weight.
 320                                      * The styled font variants are not used. */
 321 #endif
 322
 323 #if defined(FEAT_MENU) && !defined(HAVE_GTK2)
 324 # ifdef FONTSET_ALWAYS
 325     GuiFontset  menu_fontset;       /* set of fonts for multi-byte chars */
 326 # else
 327     GuiFont     menu_font;          /* menu item font */
 328 # endif
 329 #endif
 330 #ifdef FEAT_MBYTE
 331     GuiFont     wide_font;          /* 'guifontwide' font */
 332 #endif
 333 #ifdef FEAT_XFONTSET
 334     GuiFontset  fontset;            /* set of fonts for multi-byte chars */
 335 #endif
 336     guicolor_T  back_pixel;         /* Color of background */
 337     guicolor_T  norm_pixel;         /* Color of normal text */
 338     guicolor_T  def_back_pixel;     /* default Color of background */
 339     guicolor_T  def_norm_pixel;     /* default Color of normal text */
 340
 341 #ifdef FEAT_GUI_X11
 342     char        *rsrc_menu_fg_name;     /* Color of menu and dialog foregound */
 343     guicolor_T  menu_fg_pixel;          /* Same in Pixel format */
 344     char        *rsrc_menu_bg_name;     /* Color of menu and dialog backgound */
 345     guicolor_T  menu_bg_pixel;          /* Same in Pixel format */
 346     char        *rsrc_scroll_fg_name;   /* Color of scrollbar foreground */
 347     guicolor_T  scroll_fg_pixel;        /* Same in Pixel format */
 348     char        *rsrc_scroll_bg_name;   /* Color of scrollbar background */
 349     guicolor_T  scroll_bg_pixel;        /* Same in Pixel format */
 350
 351 # ifdef FEAT_GUI_MOTIF
 352     guicolor_T  menu_def_fg_pixel;  /* Default menu foreground */
 353     guicolor_T  menu_def_bg_pixel;  /* Default menu background */
 354     guicolor_T  scroll_def_fg_pixel;  /* Default scrollbar foreground */
 355     guicolor_T  scroll_def_bg_pixel;  /* Default scrollbar background */
 356 # endif
 357     Display     *dpy;               /* X display */
 358     Window      wid;                /* Window id of text area */
 359     int         visibility;         /* Is shell partially/fully obscured? */
 360     GC          text_gc;
 361     GC          back_gc;
 362     GC          invert_gc;
 363     Cursor      blank_pointer;      /* Blank pointer */
 364
 365     /* X Resources */
 366     char_u      *rsrc_font_name;    /* Resource font name, used if 'guifont'
 367                                        not set */
 368     char_u      *rsrc_bold_font_name; /* Resource bold font name */
 369     char_u      *rsrc_ital_font_name; /* Resource italic font name */
 370     char_u      *rsrc_boldital_font_name;  /* Resource bold-italic font name */
 371     char_u      *rsrc_menu_font_name;    /* Resource menu Font name */
 372     Bool        rsrc_rev_video;     /* Use reverse video? */
 373
 374     char_u      *geom;              /* Geometry, eg "80x24" */
 375     Bool        color_approx;       /* Some color was approximated */
 376 #endif
 377
 378 #ifdef FEAT_GUI_GTK
 379     int         visibility;         /* Is shell partially/fully obscured? */
 380     GdkCursor   *blank_pointer;     /* Blank pointer */
 381
 382     /* X Resources */
 383     char_u      *geom;              /* Geometry, eg "80x24" */
 384
 385     GtkWidget   *mainwin;           /* top level GTK window */
 386     GtkWidget   *formwin;           /* manages all the windows below */
 387     GtkWidget   *drawarea;          /* the "text" area */
 388 # ifdef FEAT_MENU
 389     GtkWidget   *menubar;           /* menubar */
 390 # endif
 391 # ifdef FEAT_TOOLBAR
 392     GtkWidget   *toolbar;           /* toolbar */
 393 # endif
 394 # ifdef FEAT_GUI_GNOME
 395     GtkWidget   *menubar_h;         /* menubar handle */
 396     GtkWidget   *toolbar_h;         /* toolbar handle */
 397 # endif
 398     GdkColor    *fgcolor;           /* GDK-styled foreground color */
 399     GdkColor    *bgcolor;           /* GDK-styled background color */
 400     GdkColor    *spcolor;           /* GDK-styled special color */
 401 # ifndef HAVE_GTK2
 402     GuiFont     current_font;
 403 # endif
 404     GdkGC       *text_gc;           /* cached GC for normal text */
 405 # ifdef HAVE_GTK2
 406     PangoContext     *text_context; /* the context used for all text */
 407     PangoFont        *ascii_font;   /* cached font for ASCII strings */
 408     PangoGlyphString *ascii_glyphs; /* cached code point -> glyph map */
 409 # endif
 410 # ifdef FEAT_GUI_TABLINE
 411     GtkWidget   *tabline;           /* tab pages line handle */
 412 # endif
 413
 414     GtkAccelGroup *accel_group;
 415 # ifndef HAVE_GTK2
 416     GtkWidget   *fontdlg;           /* font selection dialog window */
 417     char_u      *fontname;          /* font name from font selection dialog */
 418 # endif
 419     GtkWidget   *filedlg;           /* file selection dialog */
 420     char_u      *browse_fname;      /* file name from filedlg */
 421 #endif  /* FEAT_GUI_GTK */
 422
 423 #if defined(FEAT_GUI_TABLINE) \
 424         && (defined(FEAT_GUI_W32) || defined(FEAT_GUI_MOTIF) \
 425                  || defined(FEAT_GUI_MAC))
 426     int         tabline_height;
 427 #endif
 428
 429 #ifdef FEAT_FOOTER
 430     int         footer_height;      /* height of the message footer */
 431 #endif
 432
 433 #if defined(FEAT_TOOLBAR) \
 434         && (defined(FEAT_GUI_ATHENA) || defined(FEAT_GUI_MOTIF))
 435     int         toolbar_height;     /* height of the toolbar */
 436 #endif
 437
 438 #ifdef FEAT_BEVAL_TIP
 439     /* Tooltip properties; also used for balloon evaluation */
 440     char_u      *rsrc_tooltip_font_name; /* tooltip font name */
 441     char        *rsrc_tooltip_fg_name;  /* tooltip foreground color name */
 442     char        *rsrc_tooltip_bg_name;  /* tooltip background color name */
 443     guicolor_T  tooltip_fg_pixel;       /* tooltip foreground color */
 444     guicolor_T  tooltip_bg_pixel;       /* tooltip background color */
 445     XFontSet    tooltip_fontset;        /* tooltip fontset */
 446 #endif
 447
 448 #ifdef FEAT_GUI_MSWIN
 449     GuiFont     currFont;           /* Current font */
 450     guicolor_T  currFgColor;        /* Current foreground text color */
 451     guicolor_T  currBgColor;        /* Current background text color */
 452     guicolor_T  currSpColor;        /* Current special text color */
 453 #endif
 454
 455 #ifdef FEAT_GUI_MAC
 456     WindowPtr   VimWindow;
 457     MenuHandle  MacOSHelpMenu;      /* Help menu provided by the MacOS */
 458     int         MacOSHelpItems;     /* Nr of help-items supplied by MacOS */
 459     int         MacOSHaveCntxMenu;  /* Contextual menu available */
 460     WindowPtr   wid;                /* Window id of text area */
 461     int         visibility;         /* Is window partially/fully obscured? */
 462 #endif
 463
 464 #ifdef RISCOS
 465     int         window_handle;
 466     char_u      *window_title;
 467     int         window_title_size;
 468     int         fg_colour;              /* in 0xBBGGRR format */
 469     int         bg_colour;
 470 #endif
 471
 472 #ifdef FEAT_GUI_PHOTON
 473     PtWidget_t  *vimWindow;             /* PtWindow */
 474     PtWidget_t  *vimTextArea;           /* PtRaw */
 475     PtWidget_t  *vimContainer;          /* PtPanel */
 476 # if defined(FEAT_MENU) || defined(FEAT_TOOLBAR)
 477     PtWidget_t  *vimToolBarGroup;
 478 # endif
 479 # ifdef FEAT_MENU
 480     PtWidget_t  *vimMenuBar;
 481 # endif
 482 # ifdef FEAT_TOOLBAR
 483     PtWidget_t  *vimToolBar;
 484     int         toolbar_height;
 485 # endif
 486     PhEvent_t   *event_buffer;
 487 #endif
 488
 489 #ifdef FEAT_XIM
 490     char        *rsrc_input_method;
 491     char        *rsrc_preedit_type_name;
 492 #endif
 493 } gui_T;
 494
 495 extern gui_T gui;                       /* this is defined in gui.c */
 496
 497 /* definitions of available window positionings for gui_*_position_in_parent()
 498  */
 499 typedef enum
 500 {
 501     VW_POS_MOUSE,
 502     VW_POS_CENTER,
 503     VW_POS_TOP_CENTER
 504 } gui_win_pos_T;
 505
 506 #ifdef FIND_REPLACE_DIALOG
 507 /*
 508  * Flags used to distinguish the different contexts in which the
 509  * find/replace callback may be called.
 510  */
 511 # define FRD_FINDNEXT   1       /* Find next in find dialog */
 512 # define FRD_R_FINDNEXT 2       /* Find next in repl dialog */
 513 # define FRD_REPLACE    3       /* Replace once */
 514 # define FRD_REPLACEALL 4       /* Replace remaining matches */
 515 # define FRD_UNDO       5       /* Undo replaced text */
 516 # define FRD_TYPE_MASK   7      /* Mask for the callback type */
 517 /* Flags which change the way searching is done. */
 518 # define FRD_WHOLE_WORD 0x08    /* match whole word only */
 519 # define FRD_MATCH_CASE 0x10    /* match case */
 520 #endif
 521
 522 #ifdef HAVE_GTK2
 523 /*
 524  * Convenience macros to convert from 'encoding' to 'termencoding' and
 525  * vice versa.  If no conversion is necessary the passed-in pointer is
 526  * returned as is, without allocating any memory.  Thus additional _FREE()
 527  * macros are provided.  The _FREE() macros also set the pointer to NULL,
 528  * in order to avoid bugs due to illegal memory access only happening if
 529  * 'encoding' != utf-8...
 530  *
 531  * Defining these macros as pure expressions looks a bit tricky but
 532  * avoids depending on the context of the macro expansion.  One of the
 533  * rare occasions where the comma operator comes in handy :)
 534  *
 535  * Note: Do NOT keep the result around when handling control back to
 536  * the main Vim!  The user could change 'encoding' at any time.
 537  */
 538 # define CONVERT_TO_UTF8(String)                                \
 539     ((output_conv.vc_type == CONV_NONE || (String) == NULL)     \
 540             ? (String)                                          \
 541             : string_convert(&output_conv, (String), NULL))
 542
 543 # define CONVERT_TO_UTF8_FREE(String)                           \
 544     ((String) = ((output_conv.vc_type == CONV_NONE)             \
 545                         ? (char_u *)NULL                        \
 546                         : (vim_free(String), (char_u *)NULL)))
 547
 548 # define CONVERT_FROM_UTF8(String)                              \
 549     ((input_conv.vc_type == CONV_NONE || (String) == NULL)      \
 550             ? (String)                                          \
 551             : string_convert(&input_conv, (String), NULL))
 552
 553 # define CONVERT_FROM_UTF8_FREE(String)                         \
 554     ((String) = ((input_conv.vc_type == CONV_NONE)              \
 555                         ? (char_u *)NULL                        \
 556                         : (vim_free(String), (char_u *)NULL)))
 557
 558 #else
 559 # define CONVERT_TO_UTF8(String) (String)
 560 # define CONVERT_TO_UTF8_FREE(String) ((String) = (char_u *)NULL)
 561 # define CONVERT_FROM_UTF8(String) (String)
 562 # define CONVERT_FROM_UTF8_FREE(String) ((String) = (char_u *)NULL)
 563 #endif /* HAVE_GTK2 */