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[1024];
  65 };
  66
  67 /** max items stored in the history list */
  68 static const guint wrln_max_history_length = 32;
  69
  70 void *wrln_completion_callback_data = NULL;
  71 wrln_gcmp_pre_cb_t wrln_pre_completion_callback = NULL;
  72 wrln_gcmp_post_cb_t wrln_post_completion_callback = NULL;
  73
  74 /* move the cursor one step to the right */
  75 static inline void cursor_move_right(struct wreadln *wr)
  76 {
  77         if (wr->cursor < (int)strlen(wr->line)) {
  78                 ++wr->cursor;
  79                 if (wr->cursor >= wr->width &&
  80                     wr->start < wr->cursor - wr->width + 1)
  81                         ++wr->start;
  82         }
  83 }
  84
  85 /* move the cursor one step to the left */
  86 static inline void cursor_move_left(struct wreadln *wr)
  87 {
  88         if (wr->cursor > 0) {
  89                 if (wr->cursor == wr->start && wr->start > 0)
  90                         --wr->start;
  91                 --wr->cursor;
  92         }
  93 }
  94
  95 /* move the cursor to the end of the line */
  96 static inline void cursor_move_to_eol(struct wreadln *wr)
  97 {
  98         wr->cursor = strlen(wr->line);
  99         if (wr->cursor >= wr->width)
 100                 wr->start = wr->cursor - wr->width + 1;
 101 }
 102
 103 /* draw line buffer and update cursor position */
 104 static inline void drawline(const struct wreadln *wr)
 105 {
 106         wmove(wr->w, wr->y, wr->x);
 107         /* clear input area */
 108         whline(wr->w, ' ', wr->width);
 109         /* print visible part of the line buffer */
 110         if (wr->masked)
 111                 whline(wr->w, '*', utf8_width(wr->line) - wr->start);
 112         else
 113                 waddnstr(wr->w, wr->line + wr->start, wr->width);
 114         /* move the cursor to the correct position */
 115         wmove(wr->w, wr->y, wr->x + wr->cursor - wr->start);
 116         /* tell ncurses to redraw the screen */
 117         doupdate();
 118 }
 119
 120 /* libcurses version */
 121
 122 static gchar *
 123 _wreadln(WINDOW *w,
 124          const gchar *prompt,
 125          const gchar *initial_value,
 126          gint x1,
 127          GList **history,
 128          GCompletion *gcmp,
 129          gboolean masked)
 130 {
 131         struct wreadln wr = {
 132                 .w = w,
 133                 .masked = masked,
 134                 .cursor = 0,
 135                 .start = 0,
 136         };
 137         GList *hlist = NULL, *hcurrent = NULL;
 138         gint key = 0, i;
 139
 140         /* turn off echo */
 141         noecho();
 142         /* make shure the cursor is visible */
 143         curs_set(1);
 144         /* print prompt string */
 145         if (prompt)
 146                 waddstr(w, prompt);
 147         /* retrive y and x0 position */
 148         getyx(w, wr.y, wr.x);
 149         /* check the x1 value */
 150         if (x1 <= wr.x || x1 > COLS)
 151                 x1 = COLS;
 152         wr.width = x1 - wr.x;
 153         /* clear input area */
 154         mvwhline(w, wr.y, wr.x, ' ', wr.width);
 155
 156         if (history) {
 157                 /* append the a new line to our history list */
 158                 *history = g_list_append(*history, g_malloc0(sizeof(wr.line)));
 159                 /* hlist points to the current item in the history list */
 160                 hlist = g_list_last(*history);
 161                 hcurrent = hlist;
 162         }
 163
 164         if (initial_value == (char *)-1) {
 165                 /* get previous history entry */
 166                 if (history && hlist->prev) {
 167                         if (hlist == hcurrent)
 168                                 /* save the current line */
 169                                 g_strlcpy(hlist->data, wr.line, sizeof(wr.line));
 170
 171                         /* get previous line */
 172                         hlist = hlist->prev;
 173                         g_strlcpy(wr.line, hlist->data, sizeof(wr.line));
 174                 }
 175                 cursor_move_to_eol(&wr);
 176                 drawline(&wr);
 177         } else if (initial_value) {
 178                 /* copy the initial value to the line buffer */
 179                 g_strlcpy(wr.line, initial_value, sizeof(wr.line));
 180                 cursor_move_to_eol(&wr);
 181                 drawline(&wr);
 182         }
 183
 184         while (key != 13 && key != '\n') {
 185                 key = wgetch(w);
 186
 187                 /* check if key is a function key */
 188                 for (i = 0; i < 63; i++)
 189                         if (key == KEY_F(i)) {
 190                                 key = KEY_F(1);
 191                                 i = 64;
 192                         }
 193
 194                 switch (key) {
 195 #ifdef HAVE_GETMOUSE
 196                 case KEY_MOUSE: /* ignore mouse events */
 197 #endif
 198                 case ERR: /* ingnore errors */
 199                         break;
 200
 201                 case TAB:
 202                         if (gcmp) {
 203                                 char *prefix = NULL;
 204                                 GList *list;
 205
 206                                 if (wrln_pre_completion_callback)
 207                                         wrln_pre_completion_callback(gcmp, wr.line,
 208                                                                      wrln_completion_callback_data);
 209                                 list = g_completion_complete(gcmp, wr.line, &prefix);
 210                                 if (prefix) {
 211                                         g_strlcpy(wr.line, prefix, sizeof(wr.line));
 212                                         cursor_move_to_eol(&wr);
 213                                         g_free(prefix);
 214                                 } else
 215                                         screen_bell();
 216
 217                                 if (wrln_post_completion_callback)
 218                                         wrln_post_completion_callback(gcmp, wr.line, list,
 219                                                                       wrln_completion_callback_data);
 220                         }
 221                         break;
 222
 223                 case KEY_CTRL_G:
 224                         screen_bell();
 225                         if (history) {
 226                                 g_free(hcurrent->data);
 227                                 hcurrent->data = NULL;
 228                                 *history = g_list_delete_link(*history, hcurrent);
 229                         }
 230                         return NULL;
 231
 232                 case KEY_LEFT:
 233                 case KEY_CTRL_B:
 234                         cursor_move_left(&wr);
 235                         break;
 236                 case KEY_RIGHT:
 237                 case KEY_CTRL_F:
 238                         cursor_move_right(&wr);
 239                         break;
 240                 case KEY_HOME:
 241                 case KEY_CTRL_A:
 242                         wr.cursor = 0;
 243                         wr.start = 0;
 244                         break;
 245                 case KEY_END:
 246                 case KEY_CTRL_E:
 247                         cursor_move_to_eol(&wr);
 248                         break;
 249                 case KEY_CTRL_K:
 250                         wr.line[wr.cursor] = 0;
 251                         break;
 252                 case KEY_CTRL_U:
 253                         wr.cursor = utf8_width(wr.line);
 254                         for (i = 0; i < wr.cursor; i++)
 255                                 wr.line[i] = '\0';
 256                         wr.cursor = 0;
 257                         break;
 258                 case 127:
 259                 case KEY_BCKSPC:        /* handle backspace: copy all */
 260                 case KEY_BACKSPACE:     /* chars starting from curpos */
 261                         if (wr.cursor > 0) {/* - 1 from buf[n+1] to buf   */
 262                                 for (i = wr.cursor - 1; wr.line[i] != 0; i++)
 263                                         wr.line[i] = wr.line[i + 1];
 264                                 cursor_move_left(&wr);
 265                         }
 266                         break;
 267                 case KEY_DC:            /* handle delete key. As above */
 268                 case KEY_CTRL_D:
 269                         if (wr.cursor <= (gint)utf8_width(wr.line) - 1) {
 270                                 for (i = wr.cursor; wr.line[i] != 0; i++)
 271                                         wr.line[i] = wr.line[i + 1];
 272                         }
 273                         break;
 274                 case KEY_UP:
 275                 case KEY_CTRL_P:
 276                         /* get previous history entry */
 277                         if (history && hlist->prev) {
 278                                 if (hlist == hcurrent)
 279                                         /* save the current line */
 280                                         g_strlcpy(hlist->data, wr.line,
 281                                                   sizeof(wr.line));
 282
 283                                 /* get previous line */
 284                                 hlist = hlist->prev;
 285                                 g_strlcpy(wr.line, hlist->data,
 286                                           sizeof(wr.line));
 287                         }
 288                         cursor_move_to_eol(&wr);
 289                         break;
 290                 case KEY_DOWN:
 291                 case KEY_CTRL_N:
 292                         /* get next history entry */
 293                         if (history && hlist->next) {
 294                                 /* get next line */
 295                                 hlist = hlist->next;
 296                                 g_strlcpy(wr.line, hlist->data,
 297                                           sizeof(wr.line));
 298                         }
 299                         cursor_move_to_eol(&wr);
 300                         break;
 301
 302                 case '\n':
 303                 case 13:
 304                 case KEY_IC:
 305                 case KEY_PPAGE:
 306                 case KEY_NPAGE:
 307                 case KEY_F(1):
 308                         /* ignore char */
 309                         break;
 310                 default:
 311                         if (key >= 32) {
 312                                 if (strlen(wr.line + wr.cursor)) { /* if the cursor is */
 313                                         /* not at the last pos */
 314                                         gchar *tmp = NULL;
 315                                         gsize size = strlen(wr.line + wr.cursor) + 1;
 316
 317                                         tmp = g_malloc0(size);
 318                                         g_strlcpy (tmp, wr.line + wr.cursor, size);
 319                                         wr.line[wr.cursor] = key;
 320                                         wr.line[wr.cursor + 1] = 0;
 321                                         g_strlcat(&wr.line[wr.cursor + 1], tmp, size);
 322                                         g_free(tmp);
 323                                         cursor_move_right(&wr);
 324                                 } else {
 325                                         wr.line[wr.cursor + 1] = 0;
 326                                         wr.line[wr.cursor] = key;
 327                                         cursor_move_right(&wr);
 328                                 }
 329                         }
 330                 }
 331
 332                 drawline(&wr);
 333         }
 334
 335         /* update history */
 336         if (history) {
 337                 if (strlen(wr.line)) {
 338                         /* update the current history entry */
 339                         size_t size = strlen(wr.line) + 1;
 340                         hcurrent->data = g_realloc(hcurrent->data, size);
 341                         g_strlcpy(hcurrent->data, wr.line, size);
 342                 } else {
 343                         /* the line was empty - remove the current history entry */
 344                         g_free(hcurrent->data);
 345                         hcurrent->data = NULL;
 346                         *history = g_list_delete_link(*history, hcurrent);
 347                 }
 348
 349                 while (g_list_length(*history) > wrln_max_history_length) {
 350                         GList *first = g_list_first(*history);
 351
 352                         /* remove the oldest history entry  */
 353                         g_free(first->data);
 354                         first->data = NULL;
 355                         *history = g_list_delete_link(*history, first);
 356                 }
 357         }
 358
 359         return g_strdup(wr.line);
 360 }
 361
 362 gchar *
 363 wreadln(WINDOW *w,
 364         const gchar *prompt,
 365         const gchar *initial_value,
 366         gint x1,
 367         GList **history,
 368         GCompletion *gcmp)
 369 {
 370         return  _wreadln(w, prompt, initial_value, x1, history, gcmp, FALSE);
 371 }
 372
 373 gchar *
 374 wreadln_masked(WINDOW *w,
 375                const gchar *prompt,
 376                const gchar *initial_value,
 377                gint x1,
 378                GList **history,
 379                GCompletion *gcmp)
 380 {
 381         return  _wreadln(w, prompt, initial_value, x1, history, gcmp, TRUE);
 382 }