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 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	free(rs->history[0]);
251	memcpy(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 = 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++] = qemu_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 = qemu_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    qemu_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}
341
342/* return true if command handled */
343void readline_handle_byte(ReadLineState *rs, int ch)
344{
345    switch(rs->esc_state) {
346    case IS_NORM:
347        switch(ch) {
348        case 1:
349            readline_bol(rs);
350            break;
351        case 4:
352            readline_delete_char(rs);
353            break;
354        case 5:
355            readline_eol(rs);
356            break;
357        case 9:
358            readline_completion(rs);
359            break;
360        case 10:
361        case 13:
362            rs->cmd_buf[rs->cmd_buf_size] = '\0';
363            if (!rs->read_password)
364                readline_hist_add(rs, rs->cmd_buf);
365            monitor_printf(rs->mon, "\n");
366            rs->cmd_buf_index = 0;
367            rs->cmd_buf_size = 0;
368            rs->last_cmd_buf_index = 0;
369            rs->last_cmd_buf_size = 0;
370            rs->readline_func(rs->mon, rs->cmd_buf, rs->readline_opaque);
371            break;
372        case 23:
373            /* ^W */
374            readline_backword(rs);
375            break;
376        case 27:
377            rs->esc_state = IS_ESC;
378            break;
379        case 127:
380        case 8:
381            readline_backspace(rs);
382            break;
383	case 155:
384            rs->esc_state = IS_CSI;
385	    break;
386        default:
387            if (ch >= 32) {
388                readline_insert_char(rs, ch);
389            }
390            break;
391        }
392        break;
393    case IS_ESC:
394        if (ch == '[') {
395            rs->esc_state = IS_CSI;
396            rs->esc_param = 0;
397        } else {
398            rs->esc_state = IS_NORM;
399        }
400        break;
401    case IS_CSI:
402        switch(ch) {
403	case 'A':
404	case 'F':
405	    readline_up_char(rs);
406	    break;
407	case 'B':
408	case 'E':
409	    readline_down_char(rs);
410	    break;
411        case 'D':
412            readline_backward_char(rs);
413            break;
414        case 'C':
415            readline_forward_char(rs);
416            break;
417        case '0' ... '9':
418            rs->esc_param = rs->esc_param * 10 + (ch - '0');
419            goto the_end;
420        case '~':
421            switch(rs->esc_param) {
422            case 1:
423                readline_bol(rs);
424                break;
425            case 3:
426                readline_delete_char(rs);
427                break;
428            case 4:
429                readline_eol(rs);
430                break;
431            }
432            break;
433        default:
434            break;
435        }
436        rs->esc_state = IS_NORM;
437    the_end:
438        break;
439    }
440    readline_update(rs);
441}
442
443void readline_start(ReadLineState *rs, const char *prompt, int read_password,
444                    ReadLineFunc *readline_func, void *opaque)
445{
446    pstrcpy(rs->prompt, sizeof(rs->prompt), prompt);
447    rs->readline_func = readline_func;
448    rs->readline_opaque = opaque;
449    rs->read_password = read_password;
450    readline_restart(rs);
451}
452
453void readline_restart(ReadLineState *rs)
454{
455    rs->cmd_buf_index = 0;
456    rs->cmd_buf_size = 0;
457}
458
459const char *readline_get_history(ReadLineState *rs, unsigned int index)
460{
461    if (index >= READLINE_MAX_CMDS)
462        return NULL;
463    return rs->history[index];
464}
465
466ReadLineState *readline_init(Monitor *mon,
467                             ReadLineCompletionFunc *completion_finder)
468{
469    ReadLineState *rs = qemu_mallocz(sizeof(*rs));
470
471    rs->hist_entry = -1;
472    rs->mon = mon;
473    rs->completion_finder = completion_finder;
474
475    return rs;
476}
477
478void readline_free(ReadLineState *rs)
479{
480    if (rs) {
481        rs->mon = NULL;
482        rs->completion_finder = NULL;
483        qemu_free(rs);
484    }
485}
486