src/redis-check-aof.c

   1 /*
   2  * Copyright (c) 2009-2012, Pieter Noordhuis <pcnoordhuis at gmail dot com>
   3  * Copyright (c) 2009-2012, Salvatore Sanfilippo <antirez at gmail dot com>
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions are met:
   8  *
   9  *   * Redistributions of source code must retain the above copyright notice,
  10  *     this list of conditions and the following disclaimer.
  11  *   * Redistributions in binary form must reproduce the above copyright
  12  *     notice, this list of conditions and the following disclaimer in the
  13  *     documentation and/or other materials provided with the distribution.
  14  *   * Neither the name of Redis nor the names of its contributors may be used
  15  *     to endorse or promote products derived from this software without
  16  *     specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  21  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  22  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  28  * POSSIBILITY OF SUCH DAMAGE.
  29  */
  30
  31 #include "fmacros.h"
  32 #include <stdlib.h>
  33 #include <stdio.h>
  34 #include <string.h>
  35 #include <unistd.h>
  36 #include <sys/stat.h>
  37 #include "config.h"
  38
  39 #define ERROR(...) { \
  40     char __buf[1024]; \
  41     sprintf(__buf, __VA_ARGS__); \
  42     sprintf(error, "0x%16llx: %s", (long long)epos, __buf); \
  43 }
  44
  45 static char error[1024];
  46 static off_t epos;
  47
  48 int consumeNewline(char *buf) {
  49     if (strncmp(buf,"\r\n",2) != 0) {
  50         ERROR("Expected \\r\\n, got: %02x%02x",buf[0],buf[1]);
  51         return 0;
  52     }
  53     return 1;
  54 }
  55
  56 int readLong(FILE *fp, char prefix, long *target) {
  57     char buf[128], *eptr;
  58     epos = ftello(fp);
  59     if (fgets(buf,sizeof(buf),fp) == NULL) {
  60         return 0;
  61     }
  62     if (buf[0] != prefix) {
  63         ERROR("Expected prefix '%c', got: '%c'",buf[0],prefix);
  64         return 0;
  65     }
  66     *target = strtol(buf+1,&eptr,10);
  67     return consumeNewline(eptr);
  68 }
  69
  70 int readBytes(FILE *fp, char *target, long length) {
  71     long real;
  72     epos = ftello(fp);
  73     real = fread(target,1,length,fp);
  74     if (real != length) {
  75         ERROR("Expected to read %ld bytes, got %ld bytes",length,real);
  76         return 0;
  77     }
  78     return 1;
  79 }
  80
  81 int readString(FILE *fp, char** target) {
  82     long len;
  83     *target = NULL;
  84     if (!readLong(fp,'$',&len)) {
  85         return 0;
  86     }
  87
  88     /* Increase length to also consume \r\n */
  89     len += 2;
  90     *target = (char*)malloc(len);
  91     if (!readBytes(fp,*target,len)) {
  92         return 0;
  93     }
  94     if (!consumeNewline(*target+len-2)) {
  95         return 0;
  96     }
  97     (*target)[len-2] = '\0';
  98     return 1;
  99 }
 100
 101 int readArgc(FILE *fp, long *target) {
 102     return readLong(fp,'*',target);
 103 }
 104
 105 off_t process(FILE *fp) {
 106     long argc;
 107     off_t pos = 0;
 108     int i, multi = 0;
 109     char *str;
 110
 111     while(1) {
 112         if (!multi) pos = ftello(fp);
 113         if (!readArgc(fp, &argc)) break;
 114
 115         for (i = 0; i < argc; i++) {
 116             if (!readString(fp,&str)) break;
 117             if (i == 0) {
 118                 if (strcasecmp(str, "multi") == 0) {
 119                     if (multi++) {
 120                         ERROR("Unexpected MULTI");
 121                         break;
 122                     }
 123                 } else if (strcasecmp(str, "exec") == 0) {
 124                     if (--multi) {
 125                         ERROR("Unexpected EXEC");
 126                         break;
 127                     }
 128                 }
 129             }
 130             free(str);
 131         }
 132
 133         /* Stop if the loop did not finish */
 134         if (i < argc) {
 135             if (str) free(str);
 136             break;
 137         }
 138     }
 139
 140     if (feof(fp) && multi && strlen(error) == 0) {
 141         ERROR("Reached EOF before reading EXEC for MULTI");
 142     }
 143     if (strlen(error) > 0) {
 144         printf("%s\n", error);
 145     }
 146     return pos;
 147 }
 148
 149 int main(int argc, char **argv) {
 150     char *filename;
 151     int fix = 0;
 152
 153     if (argc < 2) {
 154         printf("Usage: %s [--fix] <file.aof>\n", argv[0]);
 155         exit(1);
 156     } else if (argc == 2) {
 157         filename = argv[1];
 158     } else if (argc == 3) {
 159         if (strcmp(argv[1],"--fix") != 0) {
 160             printf("Invalid argument: %s\n", argv[1]);
 161             exit(1);
 162         }
 163         filename = argv[2];
 164         fix = 1;
 165     } else {
 166         printf("Invalid arguments\n");
 167         exit(1);
 168     }
 169
 170     FILE *fp = fopen(filename,"r+");
 171     if (fp == NULL) {
 172         printf("Cannot open file: %s\n", filename);
 173         exit(1);
 174     }
 175
 176     struct redis_stat sb;
 177     if (redis_fstat(fileno(fp),&sb) == -1) {
 178         printf("Cannot stat file: %s\n", filename);
 179         exit(1);
 180     }
 181
 182     off_t size = sb.st_size;
 183     if (size == 0) {
 184         printf("Empty file: %s\n", filename);
 185         exit(1);
 186     }
 187
 188     off_t pos = process(fp);
 189     off_t diff = size-pos;
 190     printf("AOF analyzed: size=%lld, ok_up_to=%lld, diff=%lld\n",
 191         (long long) size, (long long) pos, (long long) diff);
 192     if (diff > 0) {
 193         if (fix) {
 194             char buf[2];
 195             printf("This will shrink the AOF from %lld bytes, with %lld bytes, to %lld bytes\n",(long long)size,(long long)diff,(long long)pos);
 196             printf("Continue? [y/N]: ");
 197             if (fgets(buf,sizeof(buf),stdin) == NULL ||
 198                 strncasecmp(buf,"y",1) != 0) {
 199                     printf("Aborting...\n");
 200                     exit(1);
 201             }
 202             if (ftruncate(fileno(fp), pos) == -1) {
 203                 printf("Failed to truncate AOF\n");
 204                 exit(1);
 205             } else {
 206                 printf("Successfully truncated AOF\n");
 207             }
 208         } else {
 209             printf("AOF is not valid\n");
 210             exit(1);
 211         }
 212     } else {
 213         printf("AOF is valid\n");
 214     }
 215
 216     fclose(fp);
 217     return 0;
 218 }