LXR qemu/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 "monitor/readline.h"
  25#include "monitor/monitor.h"
  26
  27#define IS_NORM 0
  28#define IS_ESC  1
  29#define IS_CSI  2
  30
  31#undef printf
  32#define printf do_not_use_printf
  33
  34void readline_show_prompt(ReadLineState *rs)
  35{
  36    monitor_printf(rs->mon, "%s", rs->prompt);
  37    monitor_flush(rs->mon);
  38    rs->last_cmd_buf_index = 0;
  39    rs->last_cmd_buf_size = 0;
  40    rs->esc_state = IS_NORM;
  41}
  42
  43/* update the displayed command line */
  44static void readline_update(ReadLineState *rs)
  45{
  46    int i, delta, len;
  47
  48    if (rs->cmd_buf_size != rs->last_cmd_buf_size ||
  49        memcmp(rs->cmd_buf, rs->last_cmd_buf, rs->cmd_buf_size) != 0) {
  50        for(i = 0; i < rs->last_cmd_buf_index; i++) {
  51            monitor_printf(rs->mon, "\033[D");
  52        }
  53        rs->cmd_buf[rs->cmd_buf_size] = '\0';
  54        if (rs->read_password) {
  55            len = strlen(rs->cmd_buf);
  56            for(i = 0; i < len; i++)
  57                monitor_printf(rs->mon, "*");
  58        } else {
  59            monitor_printf(rs->mon, "%s", rs->cmd_buf);
  60        }
  61        monitor_printf(rs->mon, "\033[K");
  62        memcpy(rs->last_cmd_buf, rs->cmd_buf, rs->cmd_buf_size);
  63        rs->last_cmd_buf_size = rs->cmd_buf_size;
  64        rs->last_cmd_buf_index = rs->cmd_buf_size;
  65    }
  66    if (rs->cmd_buf_index != rs->last_cmd_buf_index) {
  67        delta = rs->cmd_buf_index - rs->last_cmd_buf_index;
  68        if (delta > 0) {
  69            for(i = 0;i < delta; i++) {
  70                monitor_printf(rs->mon, "\033[C");
  71            }
  72        } else {
  73            delta = -delta;
  74            for(i = 0;i < delta; i++) {
  75                monitor_printf(rs->mon, "\033[D");
  76            }
  77        }
  78        rs->last_cmd_buf_index = rs->cmd_buf_index;
  79    }
  80    monitor_flush(rs->mon);
  81}
  82
  83static void readline_insert_char(ReadLineState *rs, int ch)
  84{
  85    if (rs->cmd_buf_index < READLINE_CMD_BUF_SIZE) {
  86        memmove(rs->cmd_buf + rs->cmd_buf_index + 1,
  87                rs->cmd_buf + rs->cmd_buf_index,
  88                rs->cmd_buf_size - rs->cmd_buf_index);
  89        rs->cmd_buf[rs->cmd_buf_index] = ch;
  90        rs->cmd_buf_size++;
  91        rs->cmd_buf_index++;
  92    }
  93}
  94
  95static void readline_backward_char(ReadLineState *rs)
  96{
  97    if (rs->cmd_buf_index > 0) {
  98        rs->cmd_buf_index--;
  99    }
 100}
 101
 102static void readline_forward_char(ReadLineState *rs)
 103{
 104    if (rs->cmd_buf_index < rs->cmd_buf_size) {
 105        rs->cmd_buf_index++;
 106    }
 107}
 108
 109static void readline_delete_char(ReadLineState *rs)
 110{
 111    if (rs->cmd_buf_index < rs->cmd_buf_size) {
 112        memmove(rs->cmd_buf + rs->cmd_buf_index,
 113                rs->cmd_buf + rs->cmd_buf_index + 1,
 114                rs->cmd_buf_size - rs->cmd_buf_index - 1);
 115        rs->cmd_buf_size--;
 116    }
 117}
 118
 119static void readline_backspace(ReadLineState *rs)
 120{
 121    if (rs->cmd_buf_index > 0) {
 122        readline_backward_char(rs);
 123        readline_delete_char(rs);
 124    }
 125}
 126
 127static void readline_backword(ReadLineState *rs)
 128{
 129    int start;
 130
 131    if (rs->cmd_buf_index == 0 || rs->cmd_buf_index > rs->cmd_buf_size) {
 132        return;
 133    }
 134
 135    start = rs->cmd_buf_index - 1;
 136
 137    /* find first word (backwards) */
 138    while (start > 0) {
 139        if (!qemu_isspace(rs->cmd_buf[start])) {
 140            break;
 141        }
 142
 143        --start;
 144    }
 145
 146    /* find first space (backwards) */
 147    while (start > 0) {
 148        if (qemu_isspace(rs->cmd_buf[start])) {
 149            ++start;
 150            break;
 151        }
 152
 153        --start;
 154    }
 155
 156    /* remove word */
 157    if (start < rs->cmd_buf_index) {
 158        memmove(rs->cmd_buf + start,
 159                rs->cmd_buf + rs->cmd_buf_index,
 160                rs->cmd_buf_size - rs->cmd_buf_index);
 161        rs->cmd_buf_size -= rs->cmd_buf_index - start;
 162        rs->cmd_buf_index = start;
 163    }
 164}
 165
 166static void readline_bol(ReadLineState *rs)
 167{
 168    rs->cmd_buf_index = 0;
 169}
 170
 171static void readline_eol(ReadLineState *rs)
 172{
 173    rs->cmd_buf_index = rs->cmd_buf_size;
 174}
 175
 176static void readline_up_char(ReadLineState *rs)
 177{
 178    int idx;
 179
 180    if (rs->hist_entry == 0)
 181        return;
 182    if (rs->hist_entry == -1) {
 183        /* Find latest entry */
 184        for (idx = 0; idx < READLINE_MAX_CMDS; idx++) {
 185            if (rs->history[idx] == NULL)
 186                break;
 187        }
 188        rs->hist_entry = idx;
 189    }
 190    rs->hist_entry--;
 191    if (rs->hist_entry >= 0) {
 192        pstrcpy(rs->cmd_buf, sizeof(rs->cmd_buf),
 193                rs->history[rs->hist_entry]);
 194        rs->cmd_buf_index = rs->cmd_buf_size = strlen(rs->cmd_buf);
 195    }
 196}
 197
 198static void readline_down_char(ReadLineState *rs)
 199{
 200    if (rs->hist_entry == -1)
 201        return;
 202    if (rs->hist_entry < READLINE_MAX_CMDS - 1 &&
 203        rs->history[++rs->hist_entry] != NULL) {
 204        pstrcpy(rs->cmd_buf, sizeof(rs->cmd_buf),
 205                rs->history[rs->hist_entry]);
 206    } else {
 207        rs->cmd_buf[0] = 0;
 208        rs->hist_entry = -1;
 209    }
 210    rs->cmd_buf_index = rs->cmd_buf_size = strlen(rs->cmd_buf);
 211}
 212
 213static void readline_hist_add(ReadLineState *rs, const char *cmdline)
 214{
 215    char *hist_entry, *new_entry;
 216    int idx;
 217
 218    if (cmdline[0] == '\0')
 219        return;
 220    new_entry = NULL;
 221    if (rs->hist_entry != -1) {
 222        /* We were editing an existing history entry: replace it */
 223        hist_entry = rs->history[rs->hist_entry];
 224        idx = rs->hist_entry;
 225        if (strcmp(hist_entry, cmdline) == 0) {
 226            goto same_entry;
 227        }
 228    }
 229    /* Search cmdline in history buffers */
 230    for (idx = 0; idx < READLINE_MAX_CMDS; idx++) {
 231        hist_entry = rs->history[idx];
 232        if (hist_entry == NULL)
 233            break;
 234        if (strcmp(hist_entry, cmdline) == 0) {
 235        same_entry:
 236            new_entry = hist_entry;
 237            /* Put this entry at the end of history */
 238            memmove(&rs->history[idx], &rs->history[idx + 1],
 239                    (READLINE_MAX_CMDS - (idx + 1)) * sizeof(char *));
 240            rs->history[READLINE_MAX_CMDS - 1] = NULL;
 241            for (; idx < READLINE_MAX_CMDS; idx++) {
 242                if (rs->history[idx] == NULL)
 243                    break;
 244            }
 245            break;
 246        }
 247    }
 248    if (idx == READLINE_MAX_CMDS) {
 249        /* Need to get one free slot */
 250        g_free(rs->history[0]);
 251        memmove(rs->history, &rs->history[1],
 252                (READLINE_MAX_CMDS - 1) * sizeof(char *));
 253        rs->history[READLINE_MAX_CMDS - 1] = NULL;
 254        idx = READLINE_MAX_CMDS - 1;
 255    }
 256    if (new_entry == NULL)
 257        new_entry = g_strdup(cmdline);
 258    rs->history[idx] = new_entry;
 259    rs->hist_entry = -1;
 260}
 261
 262/* completion support */
 263
 264void readline_add_completion(ReadLineState *rs, const char *str)
 265{
 266    if (rs->nb_completions < READLINE_MAX_COMPLETIONS) {
 267        rs->completions[rs->nb_completions++] = g_strdup(str);
 268    }
 269}
 270
 271void readline_set_completion_index(ReadLineState *rs, int index)
 272{
 273    rs->completion_index = index;
 274}
 275
 276static void readline_completion(ReadLineState *rs)
 277{
 278    Monitor *mon = cur_mon;
 279    int len, i, j, max_width, nb_cols, max_prefix;
 280    char *cmdline;
 281
 282    rs->nb_completions = 0;
 283
 284    cmdline = g_malloc(rs->cmd_buf_index + 1);
 285    memcpy(cmdline, rs->cmd_buf, rs->cmd_buf_index);
 286    cmdline[rs->cmd_buf_index] = '\0';
 287    rs->completion_finder(cmdline);
 288    g_free(cmdline);
 289
 290    /* no completion found */
 291    if (rs->nb_completions <= 0)
 292        return;
 293    if (rs->nb_completions == 1) {
 294        len = strlen(rs->completions[0]);
 295        for(i = rs->completion_index; i < len; i++) {
 296            readline_insert_char(rs, rs->completions[0][i]);
 297        }
 298        /* extra space for next argument. XXX: make it more generic */
 299        if (len > 0 && rs->completions[0][len - 1] != '/')
 300            readline_insert_char(rs, ' ');
 301    } else {
 302        monitor_printf(mon, "\n");
 303        max_width = 0;
 304        max_prefix = 0; 
 305        for(i = 0; i < rs->nb_completions; i++) {
 306            len = strlen(rs->completions[i]);
 307            if (i==0) {
 308                max_prefix = len;
 309            } else {
 310                if (len < max_prefix)
 311                    max_prefix = len;
 312                for(j=0; j<max_prefix; j++) {
 313                    if (rs->completions[i][j] != rs->completions[0][j])
 314                        max_prefix = j;
 315                }
 316            }
 317            if (len > max_width)
 318                max_width = len;
 319        }
 320        if (max_prefix > 0) 
 321            for(i = rs->completion_index; i < max_prefix; i++) {
 322                readline_insert_char(rs, rs->completions[0][i]);
 323            }
 324        max_width += 2;
 325        if (max_width < 10)
 326            max_width = 10;
 327        else if (max_width > 80)
 328            max_width = 80;
 329        nb_cols = 80 / max_width;
 330        j = 0;
 331        for(i = 0; i < rs->nb_completions; i++) {
 332            monitor_printf(rs->mon, "%-*s", max_width, rs->completions[i]);
 333            if (++j == nb_cols || i == (rs->nb_completions - 1)) {
 334                monitor_printf(rs->mon, "\n");
 335                j = 0;
 336            }
 337        }
 338        readline_show_prompt(rs);
 339    }
 340    for (i = 0; i < rs->nb_completions; i++) {
 341        g_free(rs->completions[i]);
 342    }
 343}
 344
 345/* return true if command handled */
 346void readline_handle_byte(ReadLineState *rs, int ch)
 347{
 348    switch(rs->esc_state) {
 349    case IS_NORM:
 350        switch(ch) {
 351        case 1:
 352            readline_bol(rs);
 353            break;
 354        case 4:
 355            readline_delete_char(rs);
 356            break;
 357        case 5:
 358            readline_eol(rs);
 359            break;
 360        case 9:
 361            readline_completion(rs);
 362            break;
 363        case 10:
 364        case 13:
 365            rs->cmd_buf[rs->cmd_buf_size] = '\0';
 366            if (!rs->read_password)
 367                readline_hist_add(rs, rs->cmd_buf);
 368            monitor_printf(rs->mon, "\n");
 369            rs->cmd_buf_index = 0;
 370            rs->cmd_buf_size = 0;
 371            rs->last_cmd_buf_index = 0;
 372            rs->last_cmd_buf_size = 0;
 373            rs->readline_func(rs->mon, rs->cmd_buf, rs->readline_opaque);
 374            break;
 375        case 23:
 376            /* ^W */
 377            readline_backword(rs);
 378            break;
 379        case 27:
 380            rs->esc_state = IS_ESC;
 381            break;
 382        case 127:
 383        case 8:
 384            readline_backspace(rs);
 385            break;
 386        case 155:
 387            rs->esc_state = IS_CSI;
 388            break;
 389        default:
 390            if (ch >= 32) {
 391                readline_insert_char(rs, ch);
 392            }
 393            break;
 394        }
 395        break;
 396    case IS_ESC:
 397        if (ch == '[') {
 398            rs->esc_state = IS_CSI;
 399            rs->esc_param = 0;
 400        } else {
 401            rs->esc_state = IS_NORM;
 402        }
 403        break;
 404    case IS_CSI:
 405        switch(ch) {
 406        case 'A':
 407        case 'F':
 408            readline_up_char(rs);
 409            break;
 410        case 'B':
 411        case 'E':
 412            readline_down_char(rs);
 413            break;
 414        case 'D':
 415            readline_backward_char(rs);
 416            break;
 417        case 'C':
 418            readline_forward_char(rs);
 419            break;
 420        case '0' ... '9':
 421            rs->esc_param = rs->esc_param * 10 + (ch - '0');
 422            goto the_end;
 423        case '~':
 424            switch(rs->esc_param) {
 425            case 1:
 426                readline_bol(rs);
 427                break;
 428            case 3:
 429                readline_delete_char(rs);
 430                break;
 431            case 4:
 432                readline_eol(rs);
 433                break;
 434            }
 435            break;
 436        default:
 437            break;
 438        }
 439        rs->esc_state = IS_NORM;
 440    the_end:
 441        break;
 442    }
 443    readline_update(rs);
 444}
 445
 446void readline_start(ReadLineState *rs, const char *prompt, int read_password,
 447                    ReadLineFunc *readline_func, void *opaque)
 448{
 449    pstrcpy(rs->prompt, sizeof(rs->prompt), prompt);
 450    rs->readline_func = readline_func;
 451    rs->readline_opaque = opaque;
 452    rs->read_password = read_password;
 453    readline_restart(rs);
 454}
 455
 456void readline_restart(ReadLineState *rs)
 457{
 458    rs->cmd_buf_index = 0;
 459    rs->cmd_buf_size = 0;
 460}
 461
 462const char *readline_get_history(ReadLineState *rs, unsigned int index)
 463{
 464    if (index >= READLINE_MAX_CMDS)
 465        return NULL;
 466    return rs->history[index];
 467}
 468
 469ReadLineState *readline_init(Monitor *mon,
 470                             ReadLineCompletionFunc *completion_finder)
 471{
 472    ReadLineState *rs = g_malloc0(sizeof(*rs));
 473
 474    rs->hist_entry = -1;
 475    rs->mon = mon;
 476    rs->completion_finder = completion_finder;
 477
 478    return rs;
 479}
 480