1/*
2 * QError Module
3 *
4 * Copyright (C) 2009 Red Hat Inc.
5 *
6 * Authors:
7 *  Luiz Capitulino <lcapitulino@redhat.com>
8 *
9 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
10 * See the COPYING.LIB file in the top-level directory.
11 */
12
13#include "monitor.h"
14#include "qjson.h"
15#include "qerror.h"
16#include "qemu-common.h"
17
18static void qerror_destroy_obj(QObject *obj);
19
20static const QType qerror_type = {
21    .code = QTYPE_QERROR,
22    .destroy = qerror_destroy_obj,
23};
24
25/**
26 * The 'desc' parameter is a printf-like string, the format of the format
27 * string is:
28 *
29 * %(KEY)
30 *
31 * Where KEY is a QDict key, which has to be passed to qerror_from_info().
32 *
33 * Example:
34 *
35 * "foo error on device: %(device) slot: %(slot_nr)"
36 *
37 * A single percent sign can be printed if followed by a second one,
38 * for example:
39 *
40 * "running out of foo: %(foo)%%"
41 *
42 * Please keep the entries in alphabetical order.
43 * Use "sed -n '/^static.*qerror_table\[\]/,/^};/s/QERR_/&/gp' qerror.c | sort -c"
44 * to check.
45 */
46static const QErrorStringTable qerror_table[] = {
47    {
48        .error_fmt = QERR_BAD_BUS_FOR_DEVICE,
49        .desc      = "Device '%(device)' can't go on a %(bad_bus_type) bus",
50    },
51    {
52        .error_fmt = QERR_BUS_NOT_FOUND,
53        .desc      = "Bus '%(bus)' not found",
54    },
55    {
56        .error_fmt = QERR_BUS_NO_HOTPLUG,
57        .desc      = "Bus '%(bus)' does not support hotplugging",
58    },
59    {
60        .error_fmt = QERR_COMMAND_NOT_FOUND,
61        .desc      = "The command %(name) has not been found",
62    },
63    {
64        .error_fmt = QERR_DEVICE_ENCRYPTED,
65        .desc      = "Device '%(device)' is encrypted",
66    },
67    {
68        .error_fmt = QERR_DEVICE_INIT_FAILED,
69        .desc      = "Device '%(device)' could not be initialized",
70    },
71    {
72        .error_fmt = QERR_DEVICE_IN_USE,
73        .desc      = "Device '%(device)' is in use",
74    },
75    {
76        .error_fmt = QERR_DEVICE_LOCKED,
77        .desc      = "Device '%(device)' is locked",
78    },
79    {
80        .error_fmt = QERR_DEVICE_MULTIPLE_BUSSES,
81        .desc      = "Device '%(device)' has multiple child busses",
82    },
83    {
84        .error_fmt = QERR_DEVICE_NOT_ACTIVE,
85        .desc      = "Device '%(device)' has not been activated",
86    },
87    {
88        .error_fmt = QERR_DEVICE_NOT_ENCRYPTED,
89        .desc      = "Device '%(device)' is not encrypted",
90    },
91    {
92        .error_fmt = QERR_DEVICE_NOT_FOUND,
93        .desc      = "Device '%(device)' not found",
94    },
95    {
96        .error_fmt = QERR_DEVICE_NOT_REMOVABLE,
97        .desc      = "Device '%(device)' is not removable",
98    },
99    {
100        .error_fmt = QERR_DEVICE_NO_BUS,
101        .desc      = "Device '%(device)' has no child bus",
102    },
103    {
104        .error_fmt = QERR_DEVICE_NO_HOTPLUG,
105        .desc      = "Device '%(device)' does not support hotplugging",
106    },
107    {
108        .error_fmt = QERR_DUPLICATE_ID,
109        .desc      = "Duplicate ID '%(id)' for %(object)",
110    },
111    {
112        .error_fmt = QERR_FD_NOT_FOUND,
113        .desc      = "File descriptor named '%(name)' not found",
114    },
115    {
116        .error_fmt = QERR_FD_NOT_SUPPLIED,
117        .desc      = "No file descriptor supplied via SCM_RIGHTS",
118    },
119    {
120        .error_fmt = QERR_INVALID_BLOCK_FORMAT,
121        .desc      = "Invalid block format '%(name)'",
122    },
123    {
124        .error_fmt = QERR_INVALID_PARAMETER,
125        .desc      = "Invalid parameter '%(name)'",
126    },
127    {
128        .error_fmt = QERR_INVALID_PARAMETER_TYPE,
129        .desc      = "Invalid parameter type, expected: %(expected)",
130    },
131    {
132        .error_fmt = QERR_INVALID_PARAMETER_VALUE,
133        .desc      = "Parameter '%(name)' expects %(expected)",
134    },
135    {
136        .error_fmt = QERR_INVALID_PASSWORD,
137        .desc      = "Password incorrect",
138    },
139    {
140        .error_fmt = QERR_JSON_PARSING,
141        .desc      = "Invalid JSON syntax",
142    },
143    {
144        .error_fmt = QERR_KVM_MISSING_CAP,
145        .desc      = "Using KVM without %(capability), %(feature) unavailable",
146    },
147    {
148        .error_fmt = QERR_MIGRATION_EXPECTED,
149        .desc      = "An incoming migration is expected before this command can be executed",
150    },
151    {
152        .error_fmt = QERR_MISSING_PARAMETER,
153        .desc      = "Parameter '%(name)' is missing",
154    },
155    {
156        .error_fmt = QERR_NO_BUS_FOR_DEVICE,
157        .desc      = "No '%(bus)' bus found for device '%(device)'",
158    },
159    {
160        .error_fmt = QERR_OPEN_FILE_FAILED,
161        .desc      = "Could not open '%(filename)'",
162    },
163    {
164        .error_fmt = QERR_PROPERTY_NOT_FOUND,
165        .desc      = "Property '%(device).%(property)' not found",
166    },
167    {
168        .error_fmt = QERR_PROPERTY_VALUE_BAD,
169        .desc      = "Property '%(device).%(property)' doesn't take value '%(value)'",
170    },
171    {
172        .error_fmt = QERR_PROPERTY_VALUE_IN_USE,
173        .desc      = "Property '%(device).%(property)' can't take value '%(value)', it's in use",
174    },
175    {
176        .error_fmt = QERR_PROPERTY_VALUE_NOT_FOUND,
177        .desc      = "Property '%(device).%(property)' can't find value '%(value)'",
178    },
179    {
180        .error_fmt = QERR_QMP_BAD_INPUT_OBJECT,
181        .desc      = "Expected '%(expected)' in QMP input",
182    },
183    {
184        .error_fmt = QERR_QMP_BAD_INPUT_OBJECT_MEMBER,
185        .desc      = "QMP input object member '%(member)' expects '%(expected)'",
186    },
187    {
188        .error_fmt = QERR_QMP_EXTRA_MEMBER,
189        .desc      = "QMP input object member '%(member)' is unexpected",
190    },
191    {
192        .error_fmt = QERR_SET_PASSWD_FAILED,
193        .desc      = "Could not set password",
194    },
195    {
196        .error_fmt = QERR_TOO_MANY_FILES,
197        .desc      = "Too many open files",
198    },
199    {
200        .error_fmt = QERR_UNDEFINED_ERROR,
201        .desc      = "An undefined error has ocurred",
202    },
203    {
204        .error_fmt = QERR_UNKNOWN_BLOCK_FORMAT_FEATURE,
205        .desc      = "'%(device)' uses a %(format) feature which is not "
206                     "supported by this qemu version: %(feature)",
207    },
208    {
209        .error_fmt = QERR_VNC_SERVER_FAILED,
210        .desc      = "Could not start VNC server on %(target)",
211    },
212    {}
213};
214
215/**
216 * qerror_new(): Create a new QError
217 *
218 * Return strong reference.
219 */
220QError *qerror_new(void)
221{
222    QError *qerr;
223
224    qerr = qemu_mallocz(sizeof(*qerr));
225    QOBJECT_INIT(qerr, &qerror_type);
226
227    return qerr;
228}
229
230static void GCC_FMT_ATTR(2, 3) qerror_abort(const QError *qerr,
231                                            const char *fmt, ...)
232{
233    va_list ap;
234
235    fprintf(stderr, "qerror: bad call in function '%s':\n", qerr->func);
236    fprintf(stderr, "qerror: -> ");
237
238    va_start(ap, fmt);
239    vfprintf(stderr, fmt, ap);
240    va_end(ap);
241
242    fprintf(stderr, "\nqerror: call at %s:%d\n", qerr->file, qerr->linenr);
243    abort();
244}
245
246static void GCC_FMT_ATTR(2, 0) qerror_set_data(QError *qerr,
247                                               const char *fmt, va_list *va)
248{
249    QObject *obj;
250
251    obj = qobject_from_jsonv(fmt, va);
252    if (!obj) {
253        qerror_abort(qerr, "invalid format '%s'", fmt);
254    }
255    if (qobject_type(obj) != QTYPE_QDICT) {
256        qerror_abort(qerr, "error format is not a QDict '%s'", fmt);
257    }
258
259    qerr->error = qobject_to_qdict(obj);
260
261    obj = qdict_get(qerr->error, "class");
262    if (!obj) {
263        qerror_abort(qerr, "missing 'class' key in '%s'", fmt);
264    }
265    if (qobject_type(obj) != QTYPE_QSTRING) {
266        qerror_abort(qerr, "'class' key value should be a QString");
267    }
268
269    obj = qdict_get(qerr->error, "data");
270    if (!obj) {
271        qerror_abort(qerr, "missing 'data' key in '%s'", fmt);
272    }
273    if (qobject_type(obj) != QTYPE_QDICT) {
274        qerror_abort(qerr, "'data' key value should be a QDICT");
275    }
276}
277
278static void qerror_set_desc(QError *qerr, const char *fmt)
279{
280    int i;
281
282    // FIXME: inefficient loop
283
284    for (i = 0; qerror_table[i].error_fmt; i++) {
285        if (strcmp(qerror_table[i].error_fmt, fmt) == 0) {
286            qerr->entry = &qerror_table[i];
287            return;
288        }
289    }
290
291    qerror_abort(qerr, "error format '%s' not found", fmt);
292}
293
294/**
295 * qerror_from_info(): Create a new QError from error information
296 *
297 * The information consists of:
298 *
299 * - file   the file name of where the error occurred
300 * - linenr the line number of where the error occurred
301 * - func   the function name of where the error occurred
302 * - fmt    JSON printf-like dictionary, there must exist keys 'class' and
303 *          'data'
304 * - va     va_list of all arguments specified by fmt
305 *
306 * Return strong reference.
307 */
308QError *qerror_from_info(const char *file, int linenr, const char *func,
309                         const char *fmt, va_list *va)
310{
311    QError *qerr;
312
313    qerr = qerror_new();
314    loc_save(&qerr->loc);
315    qerr->linenr = linenr;
316    qerr->file = file;
317    qerr->func = func;
318
319    if (!fmt) {
320        qerror_abort(qerr, "QDict not specified");
321    }
322
323    qerror_set_data(qerr, fmt, va);
324    qerror_set_desc(qerr, fmt);
325
326    return qerr;
327}
328
329static void parse_error(const QError *qerror, int c)
330{
331    qerror_abort(qerror, "expected '%c' in '%s'", c, qerror->entry->desc);
332}
333
334static const char *append_field(QString *outstr, const QError *qerror,
335                                const char *start)
336{
337    QObject *obj;
338    QDict *qdict;
339    QString *key_qs;
340    const char *end, *key;
341
342    if (*start != '%')
343        parse_error(qerror, '%');
344    start++;
345    if (*start != '(')
346        parse_error(qerror, '(');
347    start++;
348
349    end = strchr(start, ')');
350    if (!end)
351        parse_error(qerror, ')');
352
353    key_qs = qstring_from_substr(start, 0, end - start - 1);
354    key = qstring_get_str(key_qs);
355
356    qdict = qobject_to_qdict(qdict_get(qerror->error, "data"));
357    obj = qdict_get(qdict, key);
358    if (!obj) {
359        qerror_abort(qerror, "key '%s' not found in QDict", key);
360    }
361
362    switch (qobject_type(obj)) {
363        case QTYPE_QSTRING:
364            qstring_append(outstr, qdict_get_str(qdict, key));
365            break;
366        case QTYPE_QINT:
367            qstring_append_int(outstr, qdict_get_int(qdict, key));
368            break;
369        default:
370            qerror_abort(qerror, "invalid type '%c'", qobject_type(obj));
371    }
372
373    QDECREF(key_qs);
374    return ++end;
375}
376
377/**
378 * qerror_human(): Format QError data into human-readable string.
379 *
380 * Formats according to member 'desc' of the specified QError object.
381 */
382QString *qerror_human(const QError *qerror)
383{
384    const char *p;
385    QString *qstring;
386
387    assert(qerror->entry != NULL);
388
389    qstring = qstring_new();
390
391    for (p = qerror->entry->desc; *p != '\0';) {
392        if (*p != '%') {
393            qstring_append_chr(qstring, *p++);
394        } else if (*(p + 1) == '%') {
395            qstring_append_chr(qstring, '%');
396            p += 2;
397        } else {
398            p = append_field(qstring, qerror, p);
399        }
400    }
401
402    return qstring;
403}
404
405/**
406 * qerror_print(): Print QError data
407 *
408 * This function will print the member 'desc' of the specified QError object,
409 * it uses error_report() for this, so that the output is routed to the right
410 * place (ie. stderr or Monitor's device).
411 */
412void qerror_print(QError *qerror)
413{
414    QString *qstring = qerror_human(qerror);
415    loc_push_restore(&qerror->loc);
416    error_report("%s", qstring_get_str(qstring));
417    loc_pop(&qerror->loc);
418    QDECREF(qstring);
419}
420
421void qerror_report_internal(const char *file, int linenr, const char *func,
422                            const char *fmt, ...)
423{
424    va_list va;
425    QError *qerror;
426
427    va_start(va, fmt);
428    qerror = qerror_from_info(file, linenr, func, fmt, &va);
429    va_end(va);
430
431    if (monitor_cur_is_qmp()) {
432        monitor_set_error(cur_mon, qerror);
433    } else {
434        qerror_print(qerror);
435        QDECREF(qerror);
436    }
437}
438
439/**
440 * qobject_to_qerror(): Convert a QObject into a QError
441 */
442QError *qobject_to_qerror(const QObject *obj)
443{
444    if (qobject_type(obj) != QTYPE_QERROR) {
445        return NULL;
446    }
447
448    return container_of(obj, QError, base);
449}
450
451/**
452 * qerror_destroy_obj(): Free all memory allocated by a QError
453 */
454static void qerror_destroy_obj(QObject *obj)
455{
456    QError *qerr;
457
458    assert(obj != NULL);
459    qerr = qobject_to_qerror(obj);
460
461    QDECREF(qerr->error);
462    qemu_free(qerr);
463}
464