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         unsigned x, y;
  49
  50         /** the screen width of the input field */
  51         unsigned 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         size_t cursor;
  58
  59         /** the byte position displayed at the origin (for horizontal
  60             scrolling) */
  61         size_t 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->line[wr->cursor] == 0)
  78                 return;
  79
  80         ++wr->cursor;
  81         if (wr->cursor >= (size_t)wr->width &&
  82             wr->start < wr->cursor - wr->width + 1)
  83                 ++wr->start;
  84 }
  85
  86 /* move the cursor one step to the left */
  87 static inline void cursor_move_left(struct wreadln *wr)
  88 {
  89         if (wr->cursor == 0)
  90                 return;
  91
  92         if (wr->cursor == wr->start && wr->start > 0)
  93                 --wr->start;
  94         --wr->cursor;
  95 }
  96
  97 /* move the cursor to the end of the line */
  98 static inline void cursor_move_to_eol(struct wreadln *wr)
  99 {
 100         wr->cursor = strlen(wr->line);
 101         if (wr->cursor >= wr->width)
 102                 wr->start = wr->cursor - wr->width + 1;
 103 }
 104
 105 /* draw line buffer and update cursor position */
 106 static inline void drawline(const struct wreadln *wr)
 107 {
 108         wmove(wr->w, wr->y, wr->x);
 109         /* clear input area */
 110         whline(wr->w, ' ', wr->width);
 111         /* print visible part of the line buffer */
 112         if (wr->masked)
 113                 whline(wr->w, '*', utf8_width(wr->line) - wr->start);
 114         else
 115                 waddnstr(wr->w, wr->line + wr->start, wr->width);
 116         /* move the cursor to the correct position */
 117         wmove(wr->w, wr->y, wr->x + wr->cursor - wr->start);
 118         /* tell ncurses to redraw the screen */
 119         doupdate();
 120 }
 121
 122 static void
 123 wreadln_insert_byte(struct wreadln *wr, gint key)
 124 {
 125         size_t rest = strlen(wr->line + wr->cursor) + 1;
 126         const size_t length = 1;
 127
 128         memmove(wr->line + wr->cursor + length,
 129                 wr->line + wr->cursor, rest);
 130         wr->line[wr->cursor] = key;
 131
 132         cursor_move_right(wr);
 133 }
 134
 135 /* libcurses version */
 136
 137 static gchar *
 138 _wreadln(WINDOW *w,
 139          const gchar *prompt,
 140          const gchar *initial_value,
 141          unsigned x1,
 142          GList **history,
 143          GCompletion *gcmp,
 144          gboolean masked)
 145 {
 146         struct wreadln wr = {
 147                 .w = w,
 148                 .masked = masked,
 149                 .cursor = 0,
 150                 .start = 0,
 151         };
 152         GList *hlist = NULL, *hcurrent = NULL;
 153         gint key = 0;
 154         size_t i;
 155
 156         /* turn off echo */
 157         noecho();
 158         /* make shure the cursor is visible */
 159         curs_set(1);
 160         /* print prompt string */
 161         if (prompt)
 162                 waddstr(w, prompt);
 163         /* retrive y and x0 position */
 164         getyx(w, wr.y, wr.x);
 165         /* check the x1 value */
 166         if (x1 <= wr.x || x1 > (unsigned)COLS)
 167                 x1 = COLS;
 168         wr.width = x1 - wr.x;
 169         /* clear input area */
 170         mvwhline(w, wr.y, wr.x, ' ', wr.width);
 171
 172         if (history) {
 173                 /* append the a new line to our history list */
 174                 *history = g_list_append(*history, g_malloc0(sizeof(wr.line)));
 175                 /* hlist points to the current item in the history list */
 176                 hlist = g_list_last(*history);
 177                 hcurrent = hlist;
 178         }
 179
 180         if (initial_value == (char *)-1) {
 181                 /* get previous history entry */
 182                 if (history && hlist->prev) {
 183                         if (hlist == hcurrent)
 184                                 /* save the current line */
 185                                 g_strlcpy(hlist->data, wr.line, sizeof(wr.line));
 186
 187                         /* get previous line */
 188                         hlist = hlist->prev;
 189                         g_strlcpy(wr.line, hlist->data, sizeof(wr.line));
 190                 }
 191                 cursor_move_to_eol(&wr);
 192                 drawline(&wr);
 193         } else if (initial_value) {
 194                 /* copy the initial value to the line buffer */
 195                 g_strlcpy(wr.line, initial_value, sizeof(wr.line));
 196                 cursor_move_to_eol(&wr);
 197                 drawline(&wr);
 198         }
 199
 200         while (key != 13 && key != '\n') {
 201                 key = wgetch(w);
 202
 203                 /* check if key is a function key */
 204                 for (i = 0; i < 63; i++)
 205                         if (key == (int)KEY_F(i)) {
 206                                 key = KEY_F(1);
 207                                 i = 64;
 208                         }
 209
 210                 switch (key) {
 211 #ifdef HAVE_GETMOUSE
 212                 case KEY_MOUSE: /* ignore mouse events */
 213 #endif
 214                 case ERR: /* ingnore errors */
 215                         break;
 216
 217                 case TAB:
 218                         if (gcmp) {
 219                                 char *prefix = NULL;
 220                                 GList *list;
 221
 222                                 if (wrln_pre_completion_callback)
 223                                         wrln_pre_completion_callback(gcmp, wr.line,
 224                                                                      wrln_completion_callback_data);
 225                                 list = g_completion_complete(gcmp, wr.line, &prefix);
 226                                 if (prefix) {
 227                                         g_strlcpy(wr.line, prefix, sizeof(wr.line));
 228                                         cursor_move_to_eol(&wr);
 229                                         g_free(prefix);
 230                                 } else
 231                                         screen_bell();
 232
 233                                 if (wrln_post_completion_callback)
 234                                         wrln_post_completion_callback(gcmp, wr.line, list,
 235                                                                       wrln_completion_callback_data);
 236                         }
 237                         break;
 238
 239                 case KEY_CTRL_G:
 240                         screen_bell();
 241                         if (history) {
 242                                 g_free(hcurrent->data);
 243                                 hcurrent->data = NULL;
 244                                 *history = g_list_delete_link(*history, hcurrent);
 245                         }
 246                         return NULL;
 247
 248                 case KEY_LEFT:
 249                 case KEY_CTRL_B:
 250                         cursor_move_left(&wr);
 251                         break;
 252                 case KEY_RIGHT:
 253                 case KEY_CTRL_F:
 254                         cursor_move_right(&wr);
 255                         break;
 256                 case KEY_HOME:
 257                 case KEY_CTRL_A:
 258                         wr.cursor = 0;
 259                         wr.start = 0;
 260                         break;
 261                 case KEY_END:
 262                 case KEY_CTRL_E:
 263                         cursor_move_to_eol(&wr);
 264                         break;
 265                 case KEY_CTRL_K:
 266                         wr.line[wr.cursor] = 0;
 267                         break;
 268                 case KEY_CTRL_U:
 269                         wr.cursor = utf8_width(wr.line);
 270                         for (i = 0; i < wr.cursor; i++)
 271                                 wr.line[i] = '\0';
 272                         wr.cursor = 0;
 273                         break;
 274                 case 127:
 275                 case KEY_BCKSPC:        /* handle backspace: copy all */
 276                 case KEY_BACKSPACE:     /* chars starting from curpos */
 277                         if (wr.cursor > 0) {/* - 1 from buf[n+1] to buf   */
 278                                 for (i = wr.cursor - 1; wr.line[i] != 0; i++)
 279                                         wr.line[i] = wr.line[i + 1];
 280                                 cursor_move_left(&wr);
 281                         }
 282                         break;
 283                 case KEY_DC:            /* handle delete key. As above */
 284                 case KEY_CTRL_D:
 285                         if (wr.cursor <= utf8_width(wr.line) - 1) {
 286                                 for (i = wr.cursor; wr.line[i] != 0; i++)
 287                                         wr.line[i] = wr.line[i + 1];
 288                         }
 289                         break;
 290                 case KEY_UP:
 291                 case KEY_CTRL_P:
 292                         /* get previous history entry */
 293                         if (history && hlist->prev) {
 294                                 if (hlist == hcurrent)
 295                                         /* save the current line */
 296                                         g_strlcpy(hlist->data, wr.line,
 297                                                   sizeof(wr.line));
 298
 299                                 /* get previous line */
 300                                 hlist = hlist->prev;
 301                                 g_strlcpy(wr.line, hlist->data,
 302                                           sizeof(wr.line));
 303                         }
 304                         cursor_move_to_eol(&wr);
 305                         break;
 306                 case KEY_DOWN:
 307                 case KEY_CTRL_N:
 308                         /* get next history entry */
 309                         if (history && hlist->next) {
 310                                 /* get next line */
 311                                 hlist = hlist->next;
 312                                 g_strlcpy(wr.line, hlist->data,
 313                                           sizeof(wr.line));
 314                         }
 315                         cursor_move_to_eol(&wr);
 316                         break;
 317
 318                 case '\n':
 319                 case 13:
 320                 case KEY_IC:
 321                 case KEY_PPAGE:
 322                 case KEY_NPAGE:
 323                 case KEY_F(1):
 324                         /* ignore char */
 325                         break;
 326                 default:
 327                         if (key >= 32)
 328                                 wreadln_insert_byte(&wr, key);
 329                 }
 330
 331                 drawline(&wr);
 332         }
 333
 334         /* update history */
 335         if (history) {
 336                 if (strlen(wr.line)) {
 337                         /* update the current history entry */
 338                         size_t size = strlen(wr.line) + 1;
 339                         hcurrent->data = g_realloc(hcurrent->data, size);
 340                         g_strlcpy(hcurrent->data, wr.line, size);
 341                 } else {
 342                         /* the line was empty - remove the current history entry */
 343                         g_free(hcurrent->data);
 344                         hcurrent->data = NULL;
 345                         *history = g_list_delete_link(*history, hcurrent);
 346                 }
 347
 348                 while (g_list_length(*history) > wrln_max_history_length) {
 349                         GList *first = g_list_first(*history);
 350
 351                         /* remove the oldest history entry  */
 352                         g_free(first->data);
 353                         first->data = NULL;
 354                         *history = g_list_delete_link(*history, first);
 355                 }
 356         }
 357
 358         return g_strdup(wr.line);
 359 }
 360
 361 gchar *
 362 wreadln(WINDOW *w,
 363         const gchar *prompt,
 364         const gchar *initial_value,
 365         unsigned x1,
 366         GList **history,
 367         GCompletion *gcmp)
 368 {
 369         return  _wreadln(w, prompt, initial_value, x1, history, gcmp, FALSE);
 370 }
 371
 372 gchar *
 373 wreadln_masked(WINDOW *w,
 374                const gchar *prompt,
 375                const gchar *initial_value,
 376                unsigned x1,
 377                GList **history,
 378                GCompletion *gcmp)
 379 {
 380         return  _wreadln(w, prompt, initial_value, x1, history, gcmp, TRUE);
 381 }