readline.c

   1 /*
   2  * QEMU readline utility
   3  *
   4  * Copyright (c) 2003-2004 Fabrice Bellard
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24 #include "readline.h"
  25 #include "monitor.h"
  26
  27 #define TERM_CMD_BUF_SIZE 4095
  28 #define TERM_MAX_CMDS 64
  29 #define NB_COMPLETIONS_MAX 256
  30
  31 #define IS_NORM 0
  32 #define IS_ESC  1
  33 #define IS_CSI  2
  34
  35 #define printf do_not_use_printf
  36
  37 static char term_cmd_buf[TERM_CMD_BUF_SIZE + 1];
  38 static int term_cmd_buf_index;
  39 static int term_cmd_buf_size;
  40
  41 static char term_last_cmd_buf[TERM_CMD_BUF_SIZE + 1];
  42 static int term_last_cmd_buf_index;
  43 static int term_last_cmd_buf_size;
  44
  45 static int term_esc_state;
  46 static int term_esc_param;
  47
  48 static char *term_history[TERM_MAX_CMDS];
  49 static int term_hist_entry = -1;
  50
  51 static int nb_completions;
  52 static int completion_index;
  53 static char *completions[NB_COMPLETIONS_MAX];
  54
  55 static ReadLineFunc *term_readline_func;
  56 static int term_is_password;
  57 static char term_prompt[256];
  58 static void *term_readline_opaque;
  59
  60 void readline_show_prompt(void)
  61 {
  62     Monitor *mon = cur_mon;
  63
  64     monitor_printf(mon, "%s", term_prompt);
  65     monitor_flush(mon);
  66     term_last_cmd_buf_index = 0;
  67     term_last_cmd_buf_size = 0;
  68     term_esc_state = IS_NORM;
  69 }
  70
  71 /* update the displayed command line */
  72 static void term_update(void)
  73 {
  74     Monitor *mon = cur_mon;
  75     int i, delta, len;
  76
  77     if (term_cmd_buf_size != term_last_cmd_buf_size ||
  78         memcmp(term_cmd_buf, term_last_cmd_buf, term_cmd_buf_size) != 0) {
  79         for(i = 0; i < term_last_cmd_buf_index; i++) {
  80             monitor_printf(mon, "\033[D");
  81         }
  82         term_cmd_buf[term_cmd_buf_size] = '\0';
  83         if (term_is_password) {
  84             len = strlen(term_cmd_buf);
  85             for(i = 0; i < len; i++)
  86                 monitor_printf(mon, "*");
  87         } else {
  88             monitor_printf(mon, "%s", term_cmd_buf);
  89         }
  90         monitor_printf(mon, "\033[K");
  91         memcpy(term_last_cmd_buf, term_cmd_buf, term_cmd_buf_size);
  92         term_last_cmd_buf_size = term_cmd_buf_size;
  93         term_last_cmd_buf_index = term_cmd_buf_size;
  94     }
  95     if (term_cmd_buf_index != term_last_cmd_buf_index) {
  96         delta = term_cmd_buf_index - term_last_cmd_buf_index;
  97         if (delta > 0) {
  98             for(i = 0;i < delta; i++) {
  99                 monitor_printf(mon, "\033[C");
 100             }
 101         } else {
 102             delta = -delta;
 103             for(i = 0;i < delta; i++) {
 104                 monitor_printf(mon, "\033[D");
 105             }
 106         }
 107         term_last_cmd_buf_index = term_cmd_buf_index;
 108     }
 109     monitor_flush(mon);
 110 }
 111
 112 static void term_insert_char(int ch)
 113 {
 114     if (term_cmd_buf_index < TERM_CMD_BUF_SIZE) {
 115         memmove(term_cmd_buf + term_cmd_buf_index + 1,
 116                 term_cmd_buf + term_cmd_buf_index,
 117                 term_cmd_buf_size - term_cmd_buf_index);
 118         term_cmd_buf[term_cmd_buf_index] = ch;
 119         term_cmd_buf_size++;
 120         term_cmd_buf_index++;
 121     }
 122 }
 123
 124 static void term_backward_char(void)
 125 {
 126     if (term_cmd_buf_index > 0) {
 127         term_cmd_buf_index--;
 128     }
 129 }
 130
 131 static void term_forward_char(void)
 132 {
 133     if (term_cmd_buf_index < term_cmd_buf_size) {
 134         term_cmd_buf_index++;
 135     }
 136 }
 137
 138 static void term_delete_char(void)
 139 {
 140     if (term_cmd_buf_index < term_cmd_buf_size) {
 141         memmove(term_cmd_buf + term_cmd_buf_index,
 142                 term_cmd_buf + term_cmd_buf_index + 1,
 143                 term_cmd_buf_size - term_cmd_buf_index - 1);
 144         term_cmd_buf_size--;
 145     }
 146 }
 147
 148 static void term_backspace(void)
 149 {
 150     if (term_cmd_buf_index > 0) {
 151         term_backward_char();
 152         term_delete_char();
 153     }
 154 }
 155
 156 static void term_backword(void)
 157 {
 158     int start;
 159
 160     if (term_cmd_buf_index == 0 || term_cmd_buf_index > term_cmd_buf_size) {
 161         return;
 162     }
 163
 164     start = term_cmd_buf_index - 1;
 165
 166     /* find first word (backwards) */
 167     while (start > 0) {
 168         if (!qemu_isspace(term_cmd_buf[start])) {
 169             break;
 170         }
 171
 172         --start;
 173     }
 174
 175     /* find first space (backwards) */
 176     while (start > 0) {
 177         if (qemu_isspace(term_cmd_buf[start])) {
 178             ++start;
 179             break;
 180         }
 181
 182         --start;
 183     }
 184
 185     /* remove word */
 186     if (start < term_cmd_buf_index) {
 187         memmove(term_cmd_buf + start,
 188                 term_cmd_buf + term_cmd_buf_index,
 189                 term_cmd_buf_size - term_cmd_buf_index);
 190         term_cmd_buf_size -= term_cmd_buf_index - start;
 191         term_cmd_buf_index = start;
 192     }
 193 }
 194
 195 static void term_bol(void)
 196 {
 197     term_cmd_buf_index = 0;
 198 }
 199
 200 static void term_eol(void)
 201 {
 202     term_cmd_buf_index = term_cmd_buf_size;
 203 }
 204
 205 static void term_up_char(void)
 206 {
 207     int idx;
 208
 209     if (term_hist_entry == 0)
 210         return;
 211     if (term_hist_entry == -1) {
 212         /* Find latest entry */
 213         for (idx = 0; idx < TERM_MAX_CMDS; idx++) {
 214             if (term_history[idx] == NULL)
 215                 break;
 216         }
 217         term_hist_entry = idx;
 218     }
 219     term_hist_entry--;
 220     if (term_hist_entry >= 0) {
 221         pstrcpy(term_cmd_buf, sizeof(term_cmd_buf),
 222                 term_history[term_hist_entry]);
 223         term_cmd_buf_index = term_cmd_buf_size = strlen(term_cmd_buf);
 224     }
 225 }
 226
 227 static void term_down_char(void)
 228 {
 229     if (term_hist_entry == TERM_MAX_CMDS - 1 || term_hist_entry == -1)
 230         return;
 231     if (term_history[++term_hist_entry] != NULL) {
 232         pstrcpy(term_cmd_buf, sizeof(term_cmd_buf),
 233                 term_history[term_hist_entry]);
 234     } else {
 235         term_hist_entry = -1;
 236     }
 237     term_cmd_buf_index = term_cmd_buf_size = strlen(term_cmd_buf);
 238 }
 239
 240 static void term_hist_add(const char *cmdline)
 241 {
 242     char *hist_entry, *new_entry;
 243     int idx;
 244
 245     if (cmdline[0] == '\0')
 246         return;
 247     new_entry = NULL;
 248     if (term_hist_entry != -1) {
 249         /* We were editing an existing history entry: replace it */
 250         hist_entry = term_history[term_hist_entry];
 251         idx = term_hist_entry;
 252         if (strcmp(hist_entry, cmdline) == 0) {
 253             goto same_entry;
 254         }
 255     }
 256     /* Search cmdline in history buffers */
 257     for (idx = 0; idx < TERM_MAX_CMDS; idx++) {
 258         hist_entry = term_history[idx];
 259         if (hist_entry == NULL)
 260             break;
 261         if (strcmp(hist_entry, cmdline) == 0) {
 262         same_entry:
 263             new_entry = hist_entry;
 264             /* Put this entry at the end of history */
 265             memmove(&term_history[idx], &term_history[idx + 1],
 266                     (TERM_MAX_CMDS - idx + 1) * sizeof(char *));
 267             term_history[TERM_MAX_CMDS - 1] = NULL;
 268             for (; idx < TERM_MAX_CMDS; idx++) {
 269                 if (term_history[idx] == NULL)
 270                     break;
 271             }
 272             break;
 273         }
 274     }
 275     if (idx == TERM_MAX_CMDS) {
 276         /* Need to get one free slot */
 277         free(term_history[0]);
 278         memcpy(term_history, &term_history[1],
 279                (TERM_MAX_CMDS - 1) * sizeof(char *));
 280         term_history[TERM_MAX_CMDS - 1] = NULL;
 281         idx = TERM_MAX_CMDS - 1;
 282     }
 283     if (new_entry == NULL)
 284         new_entry = strdup(cmdline);
 285     term_history[idx] = new_entry;
 286     term_hist_entry = -1;
 287 }
 288
 289 /* completion support */
 290
 291 void readline_add_completion(const char *str)
 292 {
 293     if (nb_completions < NB_COMPLETIONS_MAX) {
 294         completions[nb_completions++] = qemu_strdup(str);
 295     }
 296 }
 297
 298 void readline_set_completion_index(int index)
 299 {
 300     completion_index = index;
 301 }
 302
 303 static void term_completion(void)
 304 {
 305     Monitor *mon = cur_mon;
 306     int len, i, j, max_width, nb_cols, max_prefix;
 307     char *cmdline;
 308
 309     nb_completions = 0;
 310
 311     cmdline = qemu_malloc(term_cmd_buf_index + 1);
 312     memcpy(cmdline, term_cmd_buf, term_cmd_buf_index);
 313     cmdline[term_cmd_buf_index] = '\0';
 314     readline_find_completion(cmdline);
 315     qemu_free(cmdline);
 316
 317     /* no completion found */
 318     if (nb_completions <= 0)
 319         return;
 320     if (nb_completions == 1) {
 321         len = strlen(completions[0]);
 322         for(i = completion_index; i < len; i++) {
 323             term_insert_char(completions[0][i]);
 324         }
 325         /* extra space for next argument. XXX: make it more generic */
 326         if (len > 0 && completions[0][len - 1] != '/')
 327             term_insert_char(' ');
 328     } else {
 329         monitor_printf(mon, "\n");
 330         max_width = 0;
 331         max_prefix = 0;
 332         for(i = 0; i < nb_completions; i++) {
 333             len = strlen(completions[i]);
 334             if (i==0) {
 335                 max_prefix = len;
 336             } else {
 337                 if (len < max_prefix)
 338                     max_prefix = len;
 339                 for(j=0; j<max_prefix; j++) {
 340                     if (completions[i][j] != completions[0][j])
 341                         max_prefix = j;
 342                 }
 343             }
 344             if (len > max_width)
 345                 max_width = len;
 346         }
 347         if (max_prefix > 0)
 348             for(i = completion_index; i < max_prefix; i++) {
 349                 term_insert_char(completions[0][i]);
 350             }
 351         max_width += 2;
 352         if (max_width < 10)
 353             max_width = 10;
 354         else if (max_width > 80)
 355             max_width = 80;
 356         nb_cols = 80 / max_width;
 357         j = 0;
 358         for(i = 0; i < nb_completions; i++) {
 359             monitor_printf(mon, "%-*s", max_width, completions[i]);
 360             if (++j == nb_cols || i == (nb_completions - 1)) {
 361                 monitor_printf(mon, "\n");
 362                 j = 0;
 363             }
 364         }
 365         readline_show_prompt();
 366     }
 367 }
 368
 369 /* return true if command handled */
 370 void readline_handle_byte(int ch)
 371 {
 372     Monitor *mon = cur_mon;
 373
 374     switch(term_esc_state) {
 375     case IS_NORM:
 376         switch(ch) {
 377         case 1:
 378             term_bol();
 379             break;
 380         case 4:
 381             term_delete_char();
 382             break;
 383         case 5:
 384             term_eol();
 385             break;
 386         case 9:
 387             term_completion();
 388             break;
 389         case 10:
 390         case 13:
 391             term_cmd_buf[term_cmd_buf_size] = '\0';
 392             if (!term_is_password)
 393                 term_hist_add(term_cmd_buf);
 394             monitor_printf(mon, "\n");
 395             term_cmd_buf_index = 0;
 396             term_cmd_buf_size = 0;
 397             term_last_cmd_buf_index = 0;
 398             term_last_cmd_buf_size = 0;
 399             /* NOTE: readline_start can be called here */
 400             term_readline_func(mon, term_cmd_buf, term_readline_opaque);
 401             break;
 402         case 23:
 403             /* ^W */
 404             term_backword();
 405             break;
 406         case 27:
 407             term_esc_state = IS_ESC;
 408             break;
 409         case 127:
 410         case 8:
 411             term_backspace();
 412             break;
 413         case 155:
 414             term_esc_state = IS_CSI;
 415             break;
 416         default:
 417             if (ch >= 32) {
 418                 term_insert_char(ch);
 419             }
 420             break;
 421         }
 422         break;
 423     case IS_ESC:
 424         if (ch == '[') {
 425             term_esc_state = IS_CSI;
 426             term_esc_param = 0;
 427         } else {
 428             term_esc_state = IS_NORM;
 429         }
 430         break;
 431     case IS_CSI:
 432         switch(ch) {
 433         case 'A':
 434         case 'F':
 435             term_up_char();
 436             break;
 437         case 'B':
 438         case 'E':
 439             term_down_char();
 440             break;
 441         case 'D':
 442             term_backward_char();
 443             break;
 444         case 'C':
 445             term_forward_char();
 446             break;
 447         case '0' ... '9':
 448             term_esc_param = term_esc_param * 10 + (ch - '0');
 449             goto the_end;
 450         case '~':
 451             switch(term_esc_param) {
 452             case 1:
 453                 term_bol();
 454                 break;
 455             case 3:
 456                 term_delete_char();
 457                 break;
 458             case 4:
 459                 term_eol();
 460                 break;
 461             }
 462             break;
 463         default:
 464             break;
 465         }
 466         term_esc_state = IS_NORM;
 467     the_end:
 468         break;
 469     }
 470     term_update();
 471 }
 472
 473 void readline_start(const char *prompt, int is_password,
 474                     ReadLineFunc *readline_func, void *opaque)
 475 {
 476     pstrcpy(term_prompt, sizeof(term_prompt), prompt);
 477     term_readline_func = readline_func;
 478     term_readline_opaque = opaque;
 479     term_is_password = is_password;
 480     term_cmd_buf_index = 0;
 481     term_cmd_buf_size = 0;
 482 }
 483
 484 const char *readline_get_history(unsigned int index)
 485 {
 486     if (index >= TERM_MAX_CMDS)
 487         return NULL;
 488     return term_history[index];
 489 }