qemu

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:
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 *
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

25
#include "qemu/osdep.h"
26
#include "qemu/readline.h"
27
#include "qemu/ctype.h"
28
#include "qemu/cutils.h"
29

30
#define IS_NORM 0
31
#define IS_ESC  1
32
#define IS_CSI  2
33
#define IS_SS3  3
34

35
void readline_show_prompt(ReadLineState *rs)
36
{
37
    rs->printf_func(rs->opaque, "%s", rs->prompt);
38
    rs->flush_func(rs->opaque);
39
    rs->last_cmd_buf_index = 0;
40
    rs->last_cmd_buf_size = 0;
41
    rs->esc_state = IS_NORM;
42
}
43

44
/* update the displayed command line */
45
static void readline_update(ReadLineState *rs)
46
{
47
    int i, delta, len;
48

49
    if (rs->cmd_buf_size != rs->last_cmd_buf_size ||
50
        memcmp(rs->cmd_buf, rs->last_cmd_buf, rs->cmd_buf_size) != 0) {
51
        for (i = 0; i < rs->last_cmd_buf_index; i++) {
52
            rs->printf_func(rs->opaque, "\033[D");
53
        }
54
        rs->cmd_buf[rs->cmd_buf_size] = '\0';
55
        if (rs->read_password) {
56
            len = strlen(rs->cmd_buf);
57
            for (i = 0; i < len; i++) {
58
                rs->printf_func(rs->opaque, "*");
59
            }
60
        } else {
61
            rs->printf_func(rs->opaque, "%s", rs->cmd_buf);
62
        }
63
        rs->printf_func(rs->opaque, "\033[K");
64
        memcpy(rs->last_cmd_buf, rs->cmd_buf, rs->cmd_buf_size);
65
        rs->last_cmd_buf_size = rs->cmd_buf_size;
66
        rs->last_cmd_buf_index = rs->cmd_buf_size;
67
    }
68
    if (rs->cmd_buf_index != rs->last_cmd_buf_index) {
69
        delta = rs->cmd_buf_index - rs->last_cmd_buf_index;
70
        if (delta > 0) {
71
            for (i = 0; i < delta; i++) {
72
                rs->printf_func(rs->opaque, "\033[C");
73
            }
74
        } else {
75
            delta = -delta;
76
            for (i = 0; i < delta; i++) {
77
                rs->printf_func(rs->opaque, "\033[D");
78
            }
79
        }
80
        rs->last_cmd_buf_index = rs->cmd_buf_index;
81
    }
82
    rs->flush_func(rs->opaque);
83
}
84

85
static void readline_insert_char(ReadLineState *rs, int ch)
86
{
87
    if (rs->cmd_buf_index < READLINE_CMD_BUF_SIZE) {
88
        memmove(rs->cmd_buf + rs->cmd_buf_index + 1,
89
                rs->cmd_buf + rs->cmd_buf_index,
90
                rs->cmd_buf_size - rs->cmd_buf_index);
91
        rs->cmd_buf[rs->cmd_buf_index] = ch;
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        rs->cmd_buf_size++;
93
        rs->cmd_buf_index++;
94
    }
95
}
96

97
static void readline_backward_char(ReadLineState *rs)
98
{
99
    if (rs->cmd_buf_index > 0) {
100
        rs->cmd_buf_index--;
101
    }
102
}
103

104
static void readline_forward_char(ReadLineState *rs)
105
{
106
    if (rs->cmd_buf_index < rs->cmd_buf_size) {
107
        rs->cmd_buf_index++;
108
    }
109
}
110

111
static void readline_delete_char(ReadLineState *rs)
112
{
113
    if (rs->cmd_buf_index < rs->cmd_buf_size) {
114
        memmove(rs->cmd_buf + rs->cmd_buf_index,
115
                rs->cmd_buf + rs->cmd_buf_index + 1,
116
                rs->cmd_buf_size - rs->cmd_buf_index - 1);
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        rs->cmd_buf_size--;
118
    }
119
}
120

121
static void readline_backspace(ReadLineState *rs)
122
{
123
    if (rs->cmd_buf_index > 0) {
124
        readline_backward_char(rs);
125
        readline_delete_char(rs);
126
    }
127
}
128

129
static void readline_backword(ReadLineState *rs)
130
{
131
    int start;
132

133
    if (rs->cmd_buf_index == 0 || rs->cmd_buf_index > rs->cmd_buf_size) {
134
        return;
135
    }
136

137
    start = rs->cmd_buf_index - 1;
138

139
    /* find first word (backwards) */
140
    while (start > 0) {
141
        if (!qemu_isspace(rs->cmd_buf[start])) {
142
            break;
143
        }
144

145
        --start;
146
    }
147

148
    /* find first space (backwards) */
149
    while (start > 0) {
150
        if (qemu_isspace(rs->cmd_buf[start])) {
151
            ++start;
152
            break;
153
        }
154

155
        --start;
156
    }
157

158
    /* remove word */
159
    if (start < rs->cmd_buf_index) {
160
        memmove(rs->cmd_buf + start,
161
                rs->cmd_buf + rs->cmd_buf_index,
162
                rs->cmd_buf_size - rs->cmd_buf_index);
163
        rs->cmd_buf_size -= rs->cmd_buf_index - start;
164
        rs->cmd_buf_index = start;
165
    }
166
}
167

168
static void readline_bol(ReadLineState *rs)
169
{
170
    rs->cmd_buf_index = 0;
171
}
172

173
static void readline_eol(ReadLineState *rs)
174
{
175
    rs->cmd_buf_index = rs->cmd_buf_size;
176
}
177

178
static void readline_up_char(ReadLineState *rs)
179
{
180
    int idx;
181

182
    if (rs->hist_entry == 0) {
183
        return;
184
    }
185
    if (rs->hist_entry == -1) {
186
        /* Find latest entry */
187
        for (idx = 0; idx < READLINE_MAX_CMDS; idx++) {
188
            if (rs->history[idx] == NULL) {
189
                break;
190
            }
191
        }
192
        rs->hist_entry = idx;
193
    }
194
    rs->hist_entry--;
195
    if (rs->hist_entry >= 0) {
196
        pstrcpy(rs->cmd_buf, sizeof(rs->cmd_buf),
197
                rs->history[rs->hist_entry]);
198
        rs->cmd_buf_index = rs->cmd_buf_size = strlen(rs->cmd_buf);
199
    }
200
}
201

202
static void readline_down_char(ReadLineState *rs)
203
{
204
    if (rs->hist_entry == -1) {
205
        return;
206
    }
207
    if (rs->hist_entry < READLINE_MAX_CMDS - 1 &&
208
        rs->history[++rs->hist_entry] != NULL) {
209
        pstrcpy(rs->cmd_buf, sizeof(rs->cmd_buf),
210
                rs->history[rs->hist_entry]);
211
    } else {
212
        rs->cmd_buf[0] = 0;
213
        rs->hist_entry = -1;
214
    }
215
    rs->cmd_buf_index = rs->cmd_buf_size = strlen(rs->cmd_buf);
216
}
217

218
static void readline_hist_add(ReadLineState *rs, const char *cmdline)
219
{
220
    char *hist_entry, *new_entry;
221
    int idx;
222

223
    if (cmdline[0] == '\0') {
224
        return;
225
    }
226
    new_entry = NULL;
227
    if (rs->hist_entry != -1) {
228
        /* We were editing an existing history entry: replace it */
229
        hist_entry = rs->history[rs->hist_entry];
230
        idx = rs->hist_entry;
231
        if (strcmp(hist_entry, cmdline) == 0) {
232
            goto same_entry;
233
        }
234
    }
235
    /* Search cmdline in history buffers */
236
    for (idx = 0; idx < READLINE_MAX_CMDS; idx++) {
237
        hist_entry = rs->history[idx];
238
        if (hist_entry == NULL) {
239
            break;
240
        }
241
        if (strcmp(hist_entry, cmdline) == 0) {
242
        same_entry:
243
            if (idx == READLINE_MAX_CMDS - 1) {
244
                return;
245
            }
246
            new_entry = hist_entry;
247
            /* Put this entry at the end of history */
248
            memmove(&rs->history[idx], &rs->history[idx + 1],
249
                    (READLINE_MAX_CMDS - (idx + 1)) * sizeof(char *));
250
            rs->history[READLINE_MAX_CMDS - 1] = NULL;
251
            for (; idx < READLINE_MAX_CMDS; idx++) {
252
                if (rs->history[idx] == NULL) {
253
                    break;
254
                }
255
            }
256
            break;
257
        }
258
    }
259
    if (idx == READLINE_MAX_CMDS) {
260
        /* Need to get one free slot */
261
        g_free(rs->history[0]);
262
        memmove(rs->history, &rs->history[1],
263
                (READLINE_MAX_CMDS - 1) * sizeof(char *));
264
        rs->history[READLINE_MAX_CMDS - 1] = NULL;
265
        idx = READLINE_MAX_CMDS - 1;
266
    }
267
    if (new_entry == NULL) {
268
        new_entry = g_strdup(cmdline);
269
    }
270
    rs->history[idx] = new_entry;
271
    rs->hist_entry = -1;
272
}
273

274
static void readline_kill_line(ReadLineState *rs)
275
{
276
    while (rs->cmd_buf_index > 0) {
277
        readline_backward_char(rs);
278
        readline_delete_char(rs);
279
    }
280
}
281

282
/* completion support */
283

284
void readline_add_completion(ReadLineState *rs, const char *str)
285
{
286
    if (rs->nb_completions < READLINE_MAX_COMPLETIONS) {
287
        int i;
288
        for (i = 0; i < rs->nb_completions; i++) {
289
            if (!strcmp(rs->completions[i], str)) {
290
                return;
291
            }
292
        }
293
        rs->completions[rs->nb_completions++] = g_strdup(str);
294
    }
295
}
296

297
void readline_add_completion_of(ReadLineState *rs,
298
                                const char *pfx, const char *str)
299
{
300
    if (!strncmp(str, pfx, strlen(pfx))) {
301
        readline_add_completion(rs, str);
302
    }
303
}
304

305
void readline_set_completion_index(ReadLineState *rs, int index)
306
{
307
    rs->completion_index = index;
308
}
309

310
static int completion_comp(const void *a, const void *b)
311
{
312
    return strcmp(*(const char **) a, *(const char **) b);
313
}
314

315
static void readline_completion(ReadLineState *rs)
316
{
317
    int len, i, j, max_width, nb_cols, max_prefix;
318
    char *cmdline;
319

320
    rs->nb_completions = 0;
321

322
    cmdline = g_strndup(rs->cmd_buf, rs->cmd_buf_index);
323
    rs->completion_finder(rs->opaque, cmdline);
324
    g_free(cmdline);
325

326
    /* no completion found */
327
    if (rs->nb_completions <= 0) {
328
        return;
329
    }
330
    if (rs->nb_completions == 1) {
331
        len = strlen(rs->completions[0]);
332
        for (i = rs->completion_index; i < len; i++) {
333
            readline_insert_char(rs, rs->completions[0][i]);
334
        }
335
        /* extra space for next argument. XXX: make it more generic */
336
        if (len > 0 && rs->completions[0][len - 1] != '/') {
337
            readline_insert_char(rs, ' ');
338
        }
339
    } else {
340
        qsort(rs->completions, rs->nb_completions, sizeof(char *),
341
              completion_comp);
342
        rs->printf_func(rs->opaque, "\n");
343
        max_width = 0;
344
        max_prefix = 0;
345
        for (i = 0; i < rs->nb_completions; i++) {
346
            len = strlen(rs->completions[i]);
347
            if (i == 0) {
348
                max_prefix = len;
349
            } else {
350
                if (len < max_prefix) {
351
                    max_prefix = len;
352
                }
353
                for (j = 0; j < max_prefix; j++) {
354
                    if (rs->completions[i][j] != rs->completions[0][j]) {
355
                        max_prefix = j;
356
                    }
357
                }
358
            }
359
            if (len > max_width) {
360
                max_width = len;
361
            }
362
        }
363
        if (max_prefix > 0)
364
            for (i = rs->completion_index; i < max_prefix; i++) {
365
                readline_insert_char(rs, rs->completions[0][i]);
366
            }
367
        max_width += 2;
368
        if (max_width < 10) {
369
            max_width = 10;
370
        } else if (max_width > 80) {
371
            max_width = 80;
372
        }
373
        nb_cols = 80 / max_width;
374
        j = 0;
375
        for (i = 0; i < rs->nb_completions; i++) {
376
            rs->printf_func(rs->opaque, "%-*s", max_width, rs->completions[i]);
377
            if (++j == nb_cols || i == (rs->nb_completions - 1)) {
378
                rs->printf_func(rs->opaque, "\n");
379
                j = 0;
380
            }
381
        }
382
        readline_show_prompt(rs);
383
    }
384
    for (i = 0; i < rs->nb_completions; i++) {
385
        g_free(rs->completions[i]);
386
    }
387
}
388

389
static void readline_clear_screen(ReadLineState *rs)
390
{
391
    rs->printf_func(rs->opaque, "\033[2J\033[1;1H");
392
    readline_show_prompt(rs);
393
}
394

395
/* return true if command handled */
396
void readline_handle_byte(ReadLineState *rs, int ch)
397
{
398
    switch (rs->esc_state) {
399
    case IS_NORM:
400
        switch (ch) {
401
        case 1:
402
            readline_bol(rs);
403
            break;
404
        case 4:
405
            readline_delete_char(rs);
406
            break;
407
        case 5:
408
            readline_eol(rs);
409
            break;
410
        case 9:
411
            readline_completion(rs);
412
            break;
413
        case 12:
414
            readline_clear_screen(rs);
415
            break;
416
        case 10: /* fallthrough */
417
        case 13:
418
            rs->cmd_buf[rs->cmd_buf_size] = '\0';
419
            if (!rs->read_password) {
420
                readline_hist_add(rs, rs->cmd_buf);
421
            }
422
            rs->printf_func(rs->opaque, "\n");
423
            rs->cmd_buf_index = 0;
424
            rs->cmd_buf_size = 0;
425
            rs->last_cmd_buf_index = 0;
426
            rs->last_cmd_buf_size = 0;
427
            rs->readline_func(rs->opaque, rs->cmd_buf, rs->readline_opaque);
428
            break;
429
        case 14:
430
            /* ^N Next line in history */
431
            readline_down_char(rs);
432
            break;
433
        case 16:
434
            /* ^P Prev line in history */
435
            readline_up_char(rs);
436
            break;
437
        case 21:
438
            /* ^U Kill backward from point to the beginning of the line. */
439
            readline_kill_line(rs);
440
            break;
441
        case 23:
442
            /* ^W */
443
            readline_backword(rs);
444
            break;
445
        case 27:
446
            rs->esc_state = IS_ESC;
447
            break;
448
        case 127: /* fallthrough */
449
        case 8:
450
            readline_backspace(rs);
451
            break;
452
        case 155:
453
            rs->esc_state = IS_CSI;
454
            break;
455
        default:
456
            if (ch >= 32) {
457
                readline_insert_char(rs, ch);
458
            }
459
            break;
460
        }
461
        break;
462
    case IS_ESC:
463
        if (ch == '[') {
464
            rs->esc_state = IS_CSI;
465
            rs->esc_param = 0;
466
        } else if (ch == 'O') {
467
            rs->esc_state = IS_SS3;
468
            rs->esc_param = 0;
469
        } else {
470
            rs->esc_state = IS_NORM;
471
        }
472
        break;
473
    case IS_CSI:
474
        switch (ch) {
475
        case 'A': /* fallthrough */
476
        case 'F':
477
            readline_up_char(rs);
478
            break;
479
        case 'B': /* fallthrough */
480
        case 'E':
481
            readline_down_char(rs);
482
            break;
483
        case 'D':
484
            readline_backward_char(rs);
485
            break;
486
        case 'C':
487
            readline_forward_char(rs);
488
            break;
489
        case '0' ... '9':
490
            rs->esc_param = rs->esc_param * 10 + (ch - '0');
491
            goto the_end;
492
        case '~':
493
            switch (rs->esc_param) {
494
            case 1:
495
                readline_bol(rs);
496
                break;
497
            case 3:
498
                readline_delete_char(rs);
499
                break;
500
            case 4:
501
                readline_eol(rs);
502
                break;
503
            default:
504
                break;
505
            }
506
            break;
507
        default:
508
            break;
509
        }
510
        rs->esc_state = IS_NORM;
511
        /* fallthrough */
512
    the_end:
513
        break;
514
    case IS_SS3:
515
        switch (ch) {
516
        case 'F':
517
            readline_eol(rs);
518
            break;
519
        case 'H':
520
            readline_bol(rs);
521
            break;
522
        default:
523
            break;
524
        }
525
        rs->esc_state = IS_NORM;
526
        break;
527
    default:
528
        break;
529
    }
530
    readline_update(rs);
531
}
532

533
void readline_start(ReadLineState *rs, const char *prompt, int read_password,
534
                    ReadLineFunc *readline_func, void *opaque)
535
{
536
    pstrcpy(rs->prompt, sizeof(rs->prompt), prompt);
537
    rs->readline_func = readline_func;
538
    rs->readline_opaque = opaque;
539
    rs->read_password = read_password;
540
    readline_restart(rs);
541
}
542

543
void readline_restart(ReadLineState *rs)
544
{
545
    rs->cmd_buf_index = 0;
546
    rs->cmd_buf_size = 0;
547
}
548

549
const char *readline_get_history(ReadLineState *rs, unsigned int index)
550
{
551
    if (index >= READLINE_MAX_CMDS) {
552
        return NULL;
553
    }
554
    return rs->history[index];
555
}
556

557
void readline_free(ReadLineState *rs)
558
{
559
    int i;
560

561
    if (!rs) {
562
        return;
563
    }
564
    for (i = 0; i < READLINE_MAX_CMDS; i++) {
565
        g_free(rs->history[i]);
566
    }
567
    g_free(rs);
568
}
569

570
ReadLineState *readline_init(ReadLinePrintfFunc *printf_func,
571
                             ReadLineFlushFunc *flush_func,
572
                             void *opaque,
573
                             ReadLineCompletionFunc *completion_finder)
574
{
575
    ReadLineState *rs = g_new0(ReadLineState, 1);
576

577
    rs->hist_entry = -1;
578
    rs->opaque = opaque;
579
    rs->printf_func = printf_func;
580
    rs->flush_func = flush_func;
581
    rs->completion_finder = completion_finder;
582

583
    return rs;
584
}
585