tool/dbtotxt.c

   1 /*
   2 ** Copyright 2008 D. Richard Hipp and Hipp, Wyrick & Company, Inc.
   3 ** All Rights Reserved
   4 **
   5 ******************************************************************************
   6 **
   7 ** This file implements a stand-alone utility program that converts
   8 ** a binary file (usually an SQLite database) into a text format that
   9 ** is compact and friendly to human-readers.
  10 **
  11 ** Usage:
  12 **
  13 **         dbtotxt [--pagesize N] FILENAME
  14 **
  15 ** The translation of the database appears on standard output.  If the
  16 ** --pagesize command-line option is omitted, then the page size is taken
  17 ** from the database header.
  18 **
  19 ** Compactness is achieved by suppressing lines of all zero bytes.  This
  20 ** works well at compressing test databases that are mostly empty.  But
  21 ** the output will probably be lengthy for a real database containing lots
  22 ** of real content.  For maximum compactness, it is suggested that test
  23 ** databases be constructed with "zeroblob()" rather than "randomblob()"
  24 ** used for filler content and with "PRAGMA secure_delete=ON" selected to
  25 ** zero-out deleted content.
  26 */
  27 #include <stdio.h>
  28 #include <string.h>
  29 #include <stdlib.h>
  30 #include <ctype.h>
  31
  32 /* Return true if the line is all zeros */
  33 static int allZero(unsigned char *aLine){
  34   int i;
  35   for(i=0; i<16 && aLine[i]==0; i++){}
  36   return i==16;
  37 }
  38
  39 int main(int argc, char **argv){
  40   int pgsz = 0;               /* page size */
  41   long szFile;                /* Size of the input file in bytes */
  42   FILE *in;                   /* Input file */
  43   int i, j;                   /* Loop counters */
  44   int nErr = 0;               /* Number of errors */
  45   const char *zInputFile = 0; /* Name of the input file */
  46   const char *zBaseName = 0;  /* Base name of the file */
  47   int lastPage = 0;           /* Last page number shown */
  48   int iPage;                  /* Current page number */
  49   unsigned char aLine[16];    /* A single line of the file */
  50   unsigned char aHdr[100];    /* File header */
  51   unsigned char bShow[256];      /* Characters ok to display */
  52   memset(bShow, '.', sizeof(bShow));
  53   for(i=' '; i<='~'; i++){
  54     if( i!='{' && i!='}' && i!='"' && i!='\\' ) bShow[i] = (unsigned char)i;
  55   }
  56   for(i=1; i<argc; i++){
  57     if( argv[i][0]=='-' ){
  58       const char *z = argv[i];
  59       z++;
  60       if( z[0]=='-' ) z++;
  61       if( strcmp(z,"pagesize")==0 ){
  62         i++;
  63         pgsz = atoi(argv[i]);
  64         if( pgsz<512 || pgsz>65536 || (pgsz&(pgsz-1))!=0 ){
  65           fprintf(stderr, "Page size must be a power of two between"
  66                           " 512 and 65536.\n");
  67           nErr++;
  68         }
  69         continue;
  70       }
  71       fprintf(stderr, "Unknown option: %s\n", argv[i]);
  72       nErr++;
  73     }else if( zInputFile ){
  74       fprintf(stderr, "Already using a different input file: [%s]\n", argv[i]);
  75       nErr++;
  76     }else{
  77       zInputFile = argv[i];
  78     }
  79   }
  80   if( zInputFile==0 ){
  81     fprintf(stderr, "No input file specified.\n");
  82     nErr++;
  83   }
  84   if( nErr ){
  85     fprintf(stderr, "Usage: %s [--pagesize N] FILENAME\n", argv[0]);
  86     exit(1);
  87   }
  88   in = fopen(zInputFile, "rb");
  89   if( in==0 ){
  90     fprintf(stderr, "Cannot open input file [%s]\n", zInputFile);
  91     exit(1);
  92   }
  93   fseek(in, 0, SEEK_END);
  94   szFile = ftell(in);
  95   rewind(in);
  96   if( szFile<100 ){
  97     fprintf(stderr, "File too short. Minimum size is 100 bytes.\n");
  98     exit(1);
  99   }
 100   if( fread(aHdr, 100, 1, in)!=1 ){
 101     fprintf(stderr, "Cannot read file header\n");
 102     exit(1);
 103   }
 104   rewind(in);
 105   if( pgsz==0 ){
 106     pgsz = (aHdr[16]<<8) | aHdr[17];
 107     if( pgsz==1 ) pgsz = 65536;
 108     if( pgsz<512 || (pgsz&(pgsz-1))!=0 ){
 109       fprintf(stderr, "Invalid page size in header: %d\n", pgsz);
 110       exit(1);
 111     }
 112   }
 113   zBaseName = zInputFile;
 114   for(i=0; zInputFile[i]; i++){
 115     if( zInputFile[i]=='/' && zInputFile[i+1]!=0 ) zBaseName = zInputFile+i+1;
 116   }
 117   printf("| size %d pagesize %d filename %s\n",(int)szFile,pgsz,zBaseName);
 118   for(i=0; i<szFile; i+=16){
 119     int got = (int)fread(aLine, 1, 16, in);
 120     if( got!=16 ){
 121       static int once = 1;
 122       if( once ){
 123         fprintf(stderr, "Could not read input file starting at byte %d\n",
 124                          i+got);
 125       }
 126       memset(aLine+got, 0, 16-got);
 127     }
 128     if( allZero(aLine) ) continue;
 129     iPage = i/pgsz + 1;
 130     if( lastPage!=iPage ){
 131       printf("| page %d offset %d\n", iPage, (iPage-1)*pgsz);
 132       lastPage = iPage;
 133     }
 134     printf("|  %5d:", i-(iPage-1)*pgsz);
 135     for(j=0; j<16; j++) printf(" %02x", aLine[j]);
 136     printf("   ");
 137     for(j=0; j<16; j++){
 138       unsigned char c = (unsigned char)aLine[j];
 139       fputc( bShow[c], stdout);
 140     }
 141     fputc('\n', stdout);
 142   }
 143   fclose(in);
 144   printf("| end %s\n", zBaseName);
 145   return 0;
 146 }