summaryrefslogtreecommitdiff
path: root/src/redis-check-aof.c
blob: a3da79dd4382bb844a60ed8c0091e964ef69f45e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
/*
 * Copyright (c) 2009-2012, Pieter Noordhuis <pcnoordhuis at gmail dot com>
 * Copyright (c) 2009-2012, Salvatore Sanfilippo <antirez at gmail dot com>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   * Redistributions of source code must retain the above copyright notice,
 *     this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *   * Neither the name of Redis nor the names of its contributors may be used
 *     to endorse or promote products derived from this software without
 *     specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "server.h"
#include <sys/stat.h>
#include <sys/types.h>
#include <regex.h>
#include <libgen.h>

#define AOF_CHECK_OK 0
#define AOF_CHECK_EMPTY 1
#define AOF_CHECK_TRUNCATED 2
#define AOF_CHECK_TIMESTAMP_TRUNCATED 3

typedef enum {
    AOF_RESP,
    AOF_RDB_PREAMBLE,
    AOF_MULTI_PART,
} input_file_type;

aofManifest *aofManifestCreate(void);
void aofManifestFree(aofManifest *am);
aofManifest *aofLoadManifestFromFile(sds am_filepath);

#define ERROR(...) { \
    char __buf[1024]; \
    snprintf(__buf, sizeof(__buf), __VA_ARGS__); \
    snprintf(error, sizeof(error), "0x%16llx: %s", (long long)epos, __buf); \
}

static char error[1044];
static off_t epos;
static long long line = 1;
static time_t to_timestamp = 0;

int consumeNewline(char *buf) {
    if (strncmp(buf,"\r\n",2) != 0) {
        ERROR("Expected \\r\\n, got: %02x%02x",buf[0],buf[1]);
        return 0;
    }
    line += 1;
    return 1;
}

int readLong(FILE *fp, char prefix, long *target) {
    char buf[128], *eptr;
    epos = ftello(fp);
    if (fgets(buf,sizeof(buf),fp) == NULL) {
        return 0;
    }
    if (buf[0] != prefix) {
        ERROR("Expected prefix '%c', got: '%c'",prefix,buf[0]);
        return 0;
    }
    *target = strtol(buf+1,&eptr,10);
    return consumeNewline(eptr);
}

int readBytes(FILE *fp, char *target, long length) {
    long real;
    epos = ftello(fp);
    real = fread(target,1,length,fp);
    if (real != length) {
        ERROR("Expected to read %ld bytes, got %ld bytes",length,real);
        return 0;
    }
    return 1;
}

int readString(FILE *fp, char** target) {
    long len;
    *target = NULL;
    if (!readLong(fp,'$',&len)) {
        return 0;
    }

    if (len < 0 || len > LONG_MAX - 2) {
        ERROR("Expected to read string of %ld bytes, which is not in the suitable range",len);
        return 0;
    }

    /* Increase length to also consume \r\n */
    len += 2;
    *target = (char*)zmalloc(len);
    if (!readBytes(fp,*target,len)) {
        zfree(*target);
        *target = NULL;
        return 0;
    }
    if (!consumeNewline(*target+len-2)) {
        zfree(*target);
        *target = NULL;
        return 0;
    }
    (*target)[len-2] = '\0';
    return 1;
}

int readArgc(FILE *fp, long *target) {
    return readLong(fp,'*',target);
}

/* Used to decode a RESP record in the AOF file to obtain the original 
 * redis command, and also check whether the command is MULTI/EXEC. If the 
 * command is MULTI, the parameter out_multi will be incremented by one, and 
 * if the command is EXEC, the parameter out_multi will be decremented 
 * by one. The parameter out_multi will be used by the upper caller to determine 
 * whether the AOF file contains unclosed transactions.
 **/
int processRESP(FILE *fp, char *filename, int *out_multi) {
    long argc;
    char *str;

    if (!readArgc(fp, &argc)) return 0;

    for (int i = 0; i < argc; i++) {
        if (!readString(fp, &str)) return 0;
        if (i == 0) {
            if (strcasecmp(str, "multi") == 0) {
                if ((*out_multi)++) {
                    ERROR("Unexpected MULTI in AOF %s", filename);
                    zfree(str);
                    return 0;
                }
            } else if (strcasecmp(str, "exec") == 0) {
                if (--(*out_multi)) {
                    ERROR("Unexpected EXEC in AOF %s", filename);
                    zfree(str);
                    return 0;
                }
            }
        }
        zfree(str);
    }

    return 1;
}

/* Used to parse an annotation in the AOF file, the annotation starts with '#' 
 * in AOF. Currently AOF only contains timestamp annotations, but this function 
 * can easily be extended to handle other annotations. 
 * 
 * The processing rule of time annotation is that once the timestamp is found to
 * be greater than 'to_timestamp', the AOF after the annotation is truncated. 
 * Note that in Multi Part AOF, this truncation is only allowed when the last_file 
 * parameter is 1.
 **/
int processAnnotations(FILE *fp, char *filename, int last_file) {
    char buf[AOF_ANNOTATION_LINE_MAX_LEN];

    epos = ftello(fp);
    if (fgets(buf, sizeof(buf), fp) == NULL) {
        printf("Failed to read annotations from AOF %s, aborting...\n", filename);
        exit(1);
    }

    if (to_timestamp && strncmp(buf, "#TS:", 4) == 0) {
        char *endptr;
        errno = 0;
        time_t ts = strtol(buf+4, &endptr, 10);
        if (errno != 0 || *endptr != '\r') {
            printf("Invalid timestamp annotation\n");
            exit(1);
        }
        if (ts <= to_timestamp) return 1;
        if (epos == 0) {
            printf("AOF %s has nothing before timestamp %ld, "
                    "aborting...\n", filename, to_timestamp);
            exit(1);
        }
        if (!last_file) {
            printf("Failed to truncate AOF %s to timestamp %ld to offset %ld because it is not the last file.\n",
                filename, to_timestamp, (long int)epos);
            printf("If you insist, please delete all files after this file according to the manifest "
                "file and delete the corresponding records in manifest file manually. Then re-run redis-check-aof.\n");
            exit(1);
        }
        /* Truncate remaining AOF if exceeding 'to_timestamp' */
        if (ftruncate(fileno(fp), epos) == -1) {
            printf("Failed to truncate AOF %s to timestamp %ld\n",
                    filename, to_timestamp);
            exit(1);
        } else {
            return 0;
        }
    }
    return 1;
}

/* Used to check the validity of a single AOF file. The AOF file can be:
 * 1. Old-style AOF
 * 2. Old-style RDB-preamble AOF
 * 3. BASE or INCR in Multi Part AOF 
 * */
int checkSingleAof(char *aof_filename, char *aof_filepath, int last_file, int fix, int preamble) {
    off_t pos = 0, diff;
    int multi = 0;
    char buf[2];

    FILE *fp = fopen(aof_filepath, "r+");
    if (fp == NULL) {
        printf("Cannot open file %s: %s, aborting...\n", aof_filepath, strerror(errno));
        exit(1);
    }

    struct redis_stat sb;
    if (redis_fstat(fileno(fp),&sb) == -1) {
        printf("Cannot stat file: %s, aborting...\n", aof_filename);
        exit(1);
    }

    off_t size = sb.st_size;
    if (size == 0) {
        return AOF_CHECK_EMPTY;
    }

    if (preamble) {
        char *argv[2] = {NULL, aof_filename};
        if (redis_check_rdb_main(2, argv, fp) == C_ERR) {
            printf("RDB preamble of AOF file is not sane, aborting.\n");
            exit(1);
        } else {
            printf("RDB preamble is OK, proceeding with AOF tail...\n");
        }
    }

    while(1) {
        if (!multi) pos = ftello(fp);
        if (fgets(buf, sizeof(buf), fp) == NULL) {
            if (feof(fp)) {
                break;
            }
            printf("Failed to read from AOF %s, aborting...\n", aof_filename);
            exit(1);
        }

        if (fseek(fp, -1, SEEK_CUR) == -1) {
            printf("Failed to fseek in AOF %s: %s", aof_filename, strerror(errno));
            exit(1);
        }
    
        if (buf[0] == '#') {
            if (!processAnnotations(fp, aof_filepath, last_file)) {
                fclose(fp);
                return AOF_CHECK_TIMESTAMP_TRUNCATED;
            }
        } else if (buf[0] == '*'){
            if (!processRESP(fp, aof_filepath, &multi)) break;
        } else {
            printf("AOF %s format error\n", aof_filename);
            break;
        }
    }

    if (feof(fp) && multi && strlen(error) == 0) {
        ERROR("Reached EOF before reading EXEC for MULTI");
    }

    if (strlen(error) > 0) {
        printf("%s\n", error);
    }

    diff = size-pos;

    /* In truncate-to-timestamp mode, just exit if there is nothing to truncate. */
    if (diff == 0 && to_timestamp) {
        printf("Truncate nothing in AOF %s to timestamp %ld\n", aof_filename, to_timestamp);
        fclose(fp);
        return AOF_CHECK_OK;
    }

    printf("AOF analyzed: filename=%s, size=%lld, ok_up_to=%lld, ok_up_to_line=%lld, diff=%lld\n",
        aof_filename, (long long) size, (long long) pos, line, (long long) diff);
    if (diff > 0) {
        if (fix) {
            if (!last_file) {
                printf("Failed to truncate AOF %s because it is not the last file\n", aof_filename);
                exit(1);
            }

            char buf[2];
            printf("This will shrink the AOF %s from %lld bytes, with %lld bytes, to %lld bytes\n",
                aof_filename, (long long)size, (long long)diff, (long long)pos);
            printf("Continue? [y/N]: ");
            if (fgets(buf, sizeof(buf), stdin) == NULL || strncasecmp(buf, "y", 1) != 0) {
                printf("Aborting...\n");
                exit(1);
            }
            if (ftruncate(fileno(fp), pos) == -1) {
                printf("Failed to truncate AOF %s\n", aof_filename);
                exit(1);
            } else {
                fclose(fp);
                return AOF_CHECK_TRUNCATED;
            }
        } else {
            printf("AOF %s is not valid. Use the --fix option to try fixing it.\n", aof_filename);
            exit(1);
        }
    }
    fclose(fp);
    return AOF_CHECK_OK;
}

/* Used to determine whether the file is a RDB file. These two possibilities:
 * 1. The file is an old style RDB-preamble AOF
 * 2. The file is a BASE AOF in Multi Part AOF
 * */
int fileIsRDB(char *filepath) {
    FILE *fp = fopen(filepath, "r");
    if (fp == NULL) {
        printf("Cannot open file %s: %s\n", filepath, strerror(errno));
        exit(1);
    }

    struct redis_stat sb;
    if (redis_fstat(fileno(fp), &sb) == -1) {
        printf("Cannot stat file: %s\n", filepath);
        exit(1);
    }

    off_t size = sb.st_size;
    if (size == 0) {
        fclose(fp);
        return 0;
    }

    if (size >= 8) {    /* There must be at least room for the RDB header. */
        char sig[5];
        int rdb_file = fread(sig, sizeof(sig), 1, fp) == 1 &&
                            memcmp(sig, "REDIS", sizeof(sig)) == 0;
        if (rdb_file) {
            fclose(fp);
            return 1;
        } 
    }

    fclose(fp);
    return 0;
}

/* Used to determine whether the file is a manifest file. */
#define MANIFEST_MAX_LINE 1024
int fileIsManifest(char *filepath) {
    int is_manifest = 0;
    FILE *fp = fopen(filepath, "r");
    if (fp == NULL) {
        printf("Cannot open file %s: %s\n", filepath, strerror(errno));
        exit(1);
    }

    struct redis_stat sb;
    if (redis_fstat(fileno(fp), &sb) == -1) {
        printf("Cannot stat file: %s\n", filepath);
        exit(1);
    }

    off_t size = sb.st_size;
    if (size == 0) {
        fclose(fp);
        return 0;
    }

    char buf[MANIFEST_MAX_LINE+1];
    while (1) {
        if (fgets(buf, MANIFEST_MAX_LINE+1, fp) == NULL) {
            if (feof(fp)) {
                break;
            } else {
                printf("Cannot read file: %s\n", filepath);
                exit(1);
            }
        }

        /* Skip comments lines */
        if (buf[0] == '#') {
            continue;
        } else if (!memcmp(buf, "file", strlen("file"))) {
            is_manifest = 1;
        }
    }

    fclose(fp);
    return is_manifest;
}

/* Get the format of the file to be checked. It can be:
 * AOF_RESP: Old-style AOF
 * AOF_RDB_PREAMBLE: Old-style RDB-preamble AOF
 * AOF_MULTI_PART: manifest in Multi Part AOF 
 * 
 * redis-check-aof tool will automatically perform different 
 * verification logic according to different file formats.
 * */
input_file_type getInputFileType(char *filepath) {
    if (fileIsManifest(filepath)) {
        return AOF_MULTI_PART;
    } else if (fileIsRDB(filepath)) {
        return AOF_RDB_PREAMBLE;
    } else {
        return AOF_RESP;
    }
}

/* Check if Multi Part AOF is valid. It will check the BASE file and INCR files 
 * at once according to the manifest instructions (this is somewhat similar to 
 * redis' AOF loading).
 * 
 * When the verification is successful, we can guarantee:
 * 1. The manifest file format is valid
 * 2. Both BASE AOF and INCR AOFs format are valid
 * 3. No BASE or INCR AOFs files are missing
 * 
 * Note that in Multi Part AOF, we only allow truncation for the last AOF file.
 * */
void checkMultiPartAof(char *dirpath, char *manifest_filepath, int fix) {
    int total_num = 0, aof_num = 0, last_file;
    int ret;

    printf("Start checking Multi Part AOF\n");
    aofManifest *am = aofLoadManifestFromFile(manifest_filepath);

    if (am->base_aof_info) total_num++;
    if (am->incr_aof_list) total_num += listLength(am->incr_aof_list);

    if (am->base_aof_info) {
        sds aof_filename = am->base_aof_info->file_name;
        sds aof_filepath = makePath(dirpath, aof_filename);
        last_file = ++aof_num == total_num;
        int aof_preable = fileIsRDB(aof_filepath);

        printf("Start to check BASE AOF (%s format).\n", aof_preable ? "RDB":"RESP");
        ret = checkSingleAof(aof_filename, aof_filepath, last_file, fix, aof_preable);
        if (ret == AOF_CHECK_OK) {
            printf("BASE AOF %s is valid\n", aof_filename);
        } else if (ret == AOF_CHECK_EMPTY) {
            printf("BASE AOF %s is empty\n", aof_filename);
        } else if (ret == AOF_CHECK_TIMESTAMP_TRUNCATED) {
            printf("Successfully truncated AOF %s to timestamp %ld\n",
                aof_filename, to_timestamp);
        } else if (ret == AOF_CHECK_TRUNCATED) {
            printf("Successfully truncated AOF %s\n", aof_filename);
        }
        sdsfree(aof_filepath);
    }

    if (listLength(am->incr_aof_list)) {
        listNode *ln;
        listIter li;

        printf("Start to check INCR files.\n");
        listRewind(am->incr_aof_list, &li);
        while ((ln = listNext(&li)) != NULL) {
            aofInfo *ai = (aofInfo*)ln->value;
            sds aof_filename = (char*)ai->file_name;
            sds aof_filepath = makePath(dirpath, aof_filename);
            last_file = ++aof_num == total_num;
            ret = checkSingleAof(aof_filename, aof_filepath, last_file, fix, 0);
            if (ret == AOF_CHECK_OK) {
                printf("INCR AOF %s is valid\n", aof_filename);
            } else if (ret == AOF_CHECK_EMPTY) {
                printf("INCR AOF %s is empty\n", aof_filename);
            } else if (ret == AOF_CHECK_TIMESTAMP_TRUNCATED) {
                printf("Successfully truncated AOF %s to timestamp %ld\n",
                    aof_filename, to_timestamp);
            } else if (ret == AOF_CHECK_TRUNCATED) {
                printf("Successfully truncated AOF %s\n", aof_filename);
            }
            sdsfree(aof_filepath);
        }
    }

    aofManifestFree(am);
    printf("All AOF files and manifest are valid\n");
}

/* Check if old style AOF is valid. Internally, it will identify whether 
 * the AOF is in RDB-preamble format, and will eventually call `checkSingleAof`
 * to do the check. */
void checkOldStyleAof(char *filepath, int fix, int preamble) {
    printf("Start checking Old-Style AOF\n");
    int ret = checkSingleAof(filepath, filepath, 1, fix, preamble);
    if (ret == AOF_CHECK_OK) {
        printf("AOF %s is valid\n", filepath);
    } else if (ret == AOF_CHECK_EMPTY) {
        printf("AOF %s is empty\n", filepath);
    } else if (ret == AOF_CHECK_TIMESTAMP_TRUNCATED) {
        printf("Successfully truncated AOF %s to timestamp %ld\n",
            filepath, to_timestamp);
    } else if (ret == AOF_CHECK_TRUNCATED) {
        printf("Successfully truncated AOF %s\n", filepath);
    }
}

int redis_check_aof_main(int argc, char **argv) {
    char *filepath;
    char temp_filepath[PATH_MAX + 1];
    char *dirpath;
    int fix = 0;

    if (argc < 2) {
        goto invalid_args;
    } else if (argc == 2) {
        filepath = argv[1];
    } else if (argc == 3) {
        if (!strcmp(argv[1], "--fix")) {
            filepath = argv[2];
            fix = 1;
        } else {
            goto invalid_args;
        }
    } else if (argc == 4) {
        if (!strcmp(argv[1], "--truncate-to-timestamp")) {
            char *endptr;
            errno = 0;
            to_timestamp = strtol(argv[2], &endptr, 10);
            if (errno != 0 || *endptr != '\0') {
                printf("Invalid timestamp, aborting...\n");
                exit(1);
            }
            filepath = argv[3];
        } else {
            goto invalid_args;
        }
    } else {
        goto invalid_args;
    }

    /* In the glibc implementation dirname may modify their argument. */
    memcpy(temp_filepath, filepath, strlen(filepath) + 1);
    dirpath = dirname(temp_filepath);

    /* Select the corresponding verification method according to the input file type. */
    input_file_type type = getInputFileType(filepath);
    switch (type) {
    case AOF_MULTI_PART:
        checkMultiPartAof(dirpath, filepath, fix);
        break;
    case AOF_RESP:
        checkOldStyleAof(filepath, fix, 0);
        break;
    case AOF_RDB_PREAMBLE:
        checkOldStyleAof(filepath, fix, 1);
        break;
    }

    exit(0);

invalid_args:
    printf("Usage: %s [--fix|--truncate-to-timestamp $timestamp] <file.manifest|file.aof>\n",
        argv[0]);
    exit(1);
}