src/wreadln.c

   1 /*
   2  * (c) 2004 by Kalle Wallin <kaw@linux.se>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program; if not, write to the Free Software
  15  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  16  *
  17  */
  18
  19 #include "wreadln.h"
  20 #include "charset.h"
  21 #include "screen_utils.h"
  22 #include "config.h"
  23
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <glib.h>
  27
  28 #define KEY_CTRL_A   1
  29 #define KEY_CTRL_B   2
  30 #define KEY_CTRL_C   3
  31 #define KEY_CTRL_D   4
  32 #define KEY_CTRL_E   5
  33 #define KEY_CTRL_F   6
  34 #define KEY_CTRL_G   7
  35 #define KEY_CTRL_K   11
  36 #define KEY_CTRL_N   14
  37 #define KEY_CTRL_P   16
  38 #define KEY_CTRL_U   21
  39 #define KEY_CTRL_Z   26
  40 #define KEY_BCKSPC   8
  41 #define TAB          9
  42
  43 struct wreadln {
  44         /** the ncurses window where this field is displayed */
  45         WINDOW *const w;
  46
  47         /** the origin coordinates in the window */
  48         gint x, y;
  49
  50         /** the screen width of the input field */
  51         gint width;
  52
  53         /** is the input masked, i.e. characters displayed as '*'? */
  54         const gboolean masked;
  55
  56         /** the byte position of the cursor */
  57         gint cursor;
  58
  59         /** the byte position displayed at the origin (for horizontal
  60             scrolling) */
  61         gint start;
  62
  63         /** the current value */
  64         gchar *line;
  65 };
  66
  67 /** max size allocated for a line */
  68 static const size_t wrln_max_line_size = 1024;
  69
  70 /** max items stored in the history list */
  71 static const guint wrln_max_history_length = 32;
  72
  73 void *wrln_completion_callback_data = NULL;
  74 wrln_gcmp_pre_cb_t wrln_pre_completion_callback = NULL;
  75 wrln_gcmp_post_cb_t wrln_post_completion_callback = NULL;
  76
  77 /* move the cursor one step to the right */
  78 static inline void cursor_move_right(struct wreadln *wr)
  79 {
  80         if (wr->cursor < (int)strlen(wr->line) &&
  81             wr->cursor < (int)wrln_max_line_size - 1) {
  82                 ++wr->cursor;
  83                 if (wr->cursor >= wr->width &&
  84                     wr->start < wr->cursor - wr->width + 1)
  85                         ++wr->start;
  86         }
  87 }
  88
  89 /* move the cursor one step to the left */
  90 static inline void cursor_move_left(struct wreadln *wr)
  91 {
  92         if (wr->cursor > 0) {
  93                 if (wr->cursor == wr->start && wr->start > 0)
  94                         --wr->start;
  95                 --wr->cursor;
  96         }
  97 }
  98
  99 /* move the cursor to the end of the line */
 100 static inline void cursor_move_to_eol(struct wreadln *wr)
 101 {
 102         wr->cursor = strlen(wr->line);
 103         if (wr->cursor >= wr->width)
 104                 wr->start = wr->cursor - wr->width + 1;
 105 }
 106
 107 /* draw line buffer and update cursor position */
 108 static inline void drawline(const struct wreadln *wr)
 109 {
 110         wmove(wr->w, wr->y, wr->x);
 111         /* clear input area */
 112         whline(wr->w, ' ', wr->width);
 113         /* print visible part of the line buffer */
 114         if (wr->masked)
 115                 whline(wr->w, '*', utf8_width(wr->line) - wr->start);
 116         else
 117                 waddnstr(wr->w, wr->line + wr->start, wr->width);
 118         /* move the cursor to the correct position */
 119         wmove(wr->w, wr->y, wr->x + wr->cursor - wr->start);
 120         /* tell ncurses to redraw the screen */
 121         doupdate();
 122 }
 123
 124 /* libcurses version */
 125
 126 static gchar *
 127 _wreadln(WINDOW *w,
 128          const gchar *prompt,
 129          const gchar *initial_value,
 130          gint x1,
 131          GList **history,
 132          GCompletion *gcmp,
 133          gboolean masked)
 134 {
 135         struct wreadln wr = {
 136                 .w = w,
 137                 .masked = masked,
 138                 .cursor = 0,
 139                 .start = 0,
 140         };
 141         GList *hlist = NULL, *hcurrent = NULL;
 142         gint key = 0, i;
 143
 144         /* allocate a line buffer */
 145         wr.line = g_malloc0(wrln_max_line_size);
 146         /* turn off echo */
 147         noecho();
 148         /* make shure the cursor is visible */
 149         curs_set(1);
 150         /* print prompt string */
 151         if (prompt)
 152                 waddstr(w, prompt);
 153         /* retrive y and x0 position */
 154         getyx(w, wr.y, wr.x);
 155         /* check the x1 value */
 156         if (x1 <= wr.x || x1 > COLS)
 157                 x1 = COLS;
 158         wr.width = x1 - wr.x;
 159         /* clear input area */
 160         mvwhline(w, wr.y, wr.x, ' ', wr.width);
 161
 162         if (history) {
 163                 /* append the a new line to our history list */
 164                 *history = g_list_append(*history, g_malloc0(wrln_max_line_size));
 165                 /* hlist points to the current item in the history list */
 166                 hlist = g_list_last(*history);
 167                 hcurrent = hlist;
 168         }
 169
 170         if (initial_value == (char *)-1) {
 171                 /* get previous history entry */
 172                 if (history && hlist->prev) {
 173                         if (hlist == hcurrent)
 174                                 /* save the current line */
 175                                 g_strlcpy(hlist->data, wr.line, wrln_max_line_size);
 176
 177                         /* get previous line */
 178                         hlist = hlist->prev;
 179                         g_strlcpy(wr.line, hlist->data, wrln_max_line_size);
 180                 }
 181                 cursor_move_to_eol(&wr);
 182                 drawline(&wr);
 183         } else if (initial_value) {
 184                 /* copy the initial value to the line buffer */
 185                 g_strlcpy(wr.line, initial_value, wrln_max_line_size);
 186                 cursor_move_to_eol(&wr);
 187                 drawline(&wr);
 188         }
 189
 190         while (key != 13 && key != '\n') {
 191                 key = wgetch(w);
 192
 193                 /* check if key is a function key */
 194                 for (i = 0; i < 63; i++)
 195                         if (key == KEY_F(i)) {
 196                                 key = KEY_F(1);
 197                                 i = 64;
 198                         }
 199
 200                 switch (key) {
 201 #ifdef HAVE_GETMOUSE
 202                 case KEY_MOUSE: /* ignore mouse events */
 203 #endif
 204                 case ERR: /* ingnore errors */
 205                         break;
 206
 207                 case TAB:
 208                         if (gcmp) {
 209                                 char *prefix = NULL;
 210                                 GList *list;
 211
 212                                 if (wrln_pre_completion_callback)
 213                                         wrln_pre_completion_callback(gcmp, wr.line,
 214                                                                      wrln_completion_callback_data);
 215                                 list = g_completion_complete(gcmp, wr.line, &prefix);
 216                                 if (prefix) {
 217                                         g_strlcpy(wr.line, prefix, wrln_max_line_size);
 218                                         cursor_move_to_eol(&wr);
 219                                         g_free(prefix);
 220                                 } else
 221                                         screen_bell();
 222
 223                                 if (wrln_post_completion_callback)
 224                                         wrln_post_completion_callback(gcmp, wr.line, list,
 225                                                                       wrln_completion_callback_data);
 226                         }
 227                         break;
 228
 229                 case KEY_CTRL_G:
 230                         screen_bell();
 231                         g_free(wr.line);
 232                         if (history) {
 233                                 g_free(hcurrent->data);
 234                                 hcurrent->data = NULL;
 235                                 *history = g_list_delete_link(*history, hcurrent);
 236                         }
 237                         return NULL;
 238
 239                 case KEY_LEFT:
 240                 case KEY_CTRL_B:
 241                         cursor_move_left(&wr);
 242                         break;
 243                 case KEY_RIGHT:
 244                 case KEY_CTRL_F:
 245                         cursor_move_right(&wr);
 246                         break;
 247                 case KEY_HOME:
 248                 case KEY_CTRL_A:
 249                         wr.cursor = 0;
 250                         wr.start = 0;
 251                         break;
 252                 case KEY_END:
 253                 case KEY_CTRL_E:
 254                         cursor_move_to_eol(&wr);
 255                         break;
 256                 case KEY_CTRL_K:
 257                         wr.line[wr.cursor] = 0;
 258                         break;
 259                 case KEY_CTRL_U:
 260                         wr.cursor = utf8_width(wr.line);
 261                         for (i = 0; i < wr.cursor; i++)
 262                                 wr.line[i] = '\0';
 263                         wr.cursor = 0;
 264                         break;
 265                 case 127:
 266                 case KEY_BCKSPC:        /* handle backspace: copy all */
 267                 case KEY_BACKSPACE:     /* chars starting from curpos */
 268                         if (wr.cursor > 0) {/* - 1 from buf[n+1] to buf   */
 269                                 for (i = wr.cursor - 1; wr.line[i] != 0; i++)
 270                                         wr.line[i] = wr.line[i + 1];
 271                                 cursor_move_left(&wr);
 272                         }
 273                         break;
 274                 case KEY_DC:            /* handle delete key. As above */
 275                 case KEY_CTRL_D:
 276                         if (wr.cursor <= (gint)utf8_width(wr.line) - 1) {
 277                                 for (i = wr.cursor; wr.line[i] != 0; i++)
 278                                         wr.line[i] = wr.line[i + 1];
 279                         }
 280                         break;
 281                 case KEY_UP:
 282                 case KEY_CTRL_P:
 283                         /* get previous history entry */
 284                         if (history && hlist->prev) {
 285                                 if (hlist == hcurrent)
 286                                         /* save the current line */
 287                                         g_strlcpy(hlist->data, wr.line,
 288                                                   wrln_max_line_size);
 289
 290                                 /* get previous line */
 291                                 hlist = hlist->prev;
 292                                 g_strlcpy(wr.line, hlist->data,
 293                                           wrln_max_line_size);
 294                         }
 295                         cursor_move_to_eol(&wr);
 296                         break;
 297                 case KEY_DOWN:
 298                 case KEY_CTRL_N:
 299                         /* get next history entry */
 300                         if (history && hlist->next) {
 301                                 /* get next line */
 302                                 hlist = hlist->next;
 303                                 g_strlcpy(wr.line, hlist->data,
 304                                           wrln_max_line_size);
 305                         }
 306                         cursor_move_to_eol(&wr);
 307                         break;
 308
 309                 case '\n':
 310                 case 13:
 311                 case KEY_IC:
 312                 case KEY_PPAGE:
 313                 case KEY_NPAGE:
 314                 case KEY_F(1):
 315                         /* ignore char */
 316                         break;
 317                 default:
 318                         if (key >= 32) {
 319                                 if (strlen(wr.line + wr.cursor)) { /* if the cursor is */
 320                                         /* not at the last pos */
 321                                         gchar *tmp = NULL;
 322                                         gsize size = strlen(wr.line + wr.cursor) + 1;
 323
 324                                         tmp = g_malloc0(size);
 325                                         g_strlcpy (tmp, wr.line + wr.cursor, size);
 326                                         wr.line[wr.cursor] = key;
 327                                         wr.line[wr.cursor + 1] = 0;
 328                                         g_strlcat(&wr.line[wr.cursor + 1], tmp, size);
 329                                         g_free(tmp);
 330                                         cursor_move_right(&wr);
 331                                 } else {
 332                                         wr.line[wr.cursor + 1] = 0;
 333                                         wr.line[wr.cursor] = key;
 334                                         cursor_move_right(&wr);
 335                                 }
 336                         }
 337                 }
 338
 339                 drawline(&wr);
 340         }
 341
 342         /* update history */
 343         if (history) {
 344                 if (strlen(wr.line)) {
 345                         /* update the current history entry */
 346                         size_t size = strlen(wr.line) + 1;
 347                         hcurrent->data = g_realloc(hcurrent->data, size);
 348                         g_strlcpy(hcurrent->data, wr.line, size);
 349                 } else {
 350                         /* the line was empty - remove the current history entry */
 351                         g_free(hcurrent->data);
 352                         hcurrent->data = NULL;
 353                         *history = g_list_delete_link(*history, hcurrent);
 354                 }
 355
 356                 while (g_list_length(*history) > wrln_max_history_length) {
 357                         GList *first = g_list_first(*history);
 358
 359                         /* remove the oldest history entry  */
 360                         g_free(first->data);
 361                         first->data = NULL;
 362                         *history = g_list_delete_link(*history, first);
 363                 }
 364         }
 365
 366         return g_realloc(wr.line, strlen(wr.line) + 1);
 367 }
 368
 369 gchar *
 370 wreadln(WINDOW *w,
 371         const gchar *prompt,
 372         const gchar *initial_value,
 373         gint x1,
 374         GList **history,
 375         GCompletion *gcmp)
 376 {
 377         return  _wreadln(w, prompt, initial_value, x1, history, gcmp, FALSE);
 378 }
 379
 380 gchar *
 381 wreadln_masked(WINDOW *w,
 382                const gchar *prompt,
 383                const gchar *initial_value,
 384                gint x1,
 385                GList **history,
 386                GCompletion *gcmp)
 387 {
 388         return  _wreadln(w, prompt, initial_value, x1, history, gcmp, TRUE);
 389 }