redis-check-aof.c

   1 #include <stdlib.h>
   2 #include <stdio.h>
   3 #include <string.h>
   4 #include <sys/stat.h>
   5 #include "config.h"
   6
   7 #define ERROR(...) { \
   8     char __buf[1024]; \
   9     sprintf(__buf, __VA_ARGS__); \
  10     sprintf(error, "0x%08lx: %s", epos, __buf); \
  11 }
  12
  13 static char error[1024];
  14 static long epos;
  15
  16 int consumeNewline(char *buf) {
  17     if (strncmp(buf,"\r\n",2) != 0) {
  18         ERROR("Expected \\r\\n, got: %02x%02x",buf[0],buf[1]);
  19         return 0;
  20     }
  21     return 1;
  22 }
  23
  24 int readLong(FILE *fp, char prefix, long *target) {
  25     char buf[128], *eptr;
  26     epos = ftell(fp);
  27     if (fgets(buf,sizeof(buf),fp) == NULL) {
  28         return 0;
  29     }
  30     if (buf[0] != prefix) {
  31         ERROR("Expected prefix '%c', got: '%c'",buf[0],prefix);
  32         return 0;
  33     }
  34     *target = strtol(buf+1,&eptr,10);
  35     return consumeNewline(eptr);
  36 }
  37
  38 int readBytes(FILE *fp, char *target, long length) {
  39     long real;
  40     epos = ftell(fp);
  41     real = fread(target,1,length,fp);
  42     if (real != length) {
  43         ERROR("Expected to read %ld bytes, got %ld bytes",length,real);
  44         return 0;
  45     }
  46     return 1;
  47 }
  48
  49 int readString(FILE *fp, char** target) {
  50     long len;
  51     *target = NULL;
  52     if (!readLong(fp,'$',&len)) {
  53         return 0;
  54     }
  55
  56     /* Increase length to also consume \r\n */
  57     len += 2;
  58     *target = (char*)malloc(len);
  59     if (!readBytes(fp,*target,len)) {
  60         free(*target);
  61         *target = NULL;
  62         return 0;
  63     }
  64     if (!consumeNewline(*target+len-2)) {
  65         free(*target);
  66         *target = NULL;
  67         return 0;
  68     }
  69     (*target)[len-2] = '\0';
  70     return 1;
  71 }
  72
  73 int readArgc(FILE *fp, long *target) {
  74     return readLong(fp,'*',target);
  75 }
  76
  77 long process(FILE *fp) {
  78     long argc, pos = 0;
  79     int i, multi = 0;
  80     char *str;
  81
  82     while(1) {
  83         if (!multi) pos = ftell(fp);
  84         if (!readArgc(fp, &argc)) {
  85             break;
  86         }
  87
  88         for (i = 0; i < argc; i++) {
  89             if (!readString(fp,&str)) {
  90                 break;
  91             }
  92             if (i == 0) {
  93                 if (strcasecmp(str, "multi") == 0) {
  94                     if (multi++) {
  95                         ERROR("Unexpected MULTI");
  96                         break;
  97                     }
  98                 } else if (strcasecmp(str, "exec") == 0) {
  99                     if (--multi) {
 100                         ERROR("Unexpected EXEC");
 101                         break;
 102                     }
 103                 }
 104             }
 105             free(str);
 106         }
 107
 108         /* Check if loop was finished */
 109         if (i < argc) {
 110             if (str) free(str);
 111             break;
 112         }
 113     }
 114
 115     if (feof(fp) && multi && strlen(error) == 0) {
 116         ERROR("Reached EOF before reading EXEC for MULTI");
 117     }
 118
 119     if (strlen(error) > 0) {
 120         printf("%s\n", error);
 121     }
 122
 123     return pos;
 124 }
 125
 126 int main(int argc, char **argv) {
 127     /* expect the first argument to be the dump file */
 128     if (argc <= 1) {
 129         printf("Usage: %s <file.aof>\n", argv[0]);
 130         exit(0);
 131     }
 132
 133     FILE *fp = fopen(argv[1],"r");
 134     if (fp == NULL) {
 135         printf("Cannot open file: %s\n", argv[1]);
 136         exit(1);
 137     }
 138
 139     struct redis_stat sb;
 140     if (redis_fstat(fileno(fp),&sb) == -1) {
 141         printf("Cannot stat file: %s\n", argv[1]);
 142         exit(1);
 143     }
 144
 145     long size = sb.st_size;
 146     if (size == 0) {
 147         printf("Empty file: %s\n", argv[1]);
 148         exit(1);
 149     }
 150
 151     long pos = process(fp);
 152     if (pos < size) {
 153         printf("First invalid operation at offset %ld.\n", pos);
 154         exit(1);
 155     } else {
 156         printf("AOF is valid.\n");
 157     }
 158
 159     fclose(fp);
 160     return 0;
 161 }