69 строки
1.8 KiB
C
69 строки
1.8 KiB
C
|
/*
|
||
|
|
** Try to enlarge an SQLite database by appending many unused pages.
|
||
|
|
** The resulting database will fail PRAGMA integrity_check due to the
|
||
|
|
** appended unused pages, but it should work otherwise.
|
||
|
|
**
|
||
|
|
** Usage:
|
||
|
|
**
|
||
|
|
** enlargedb DATABASE N
|
||
|
|
**
|
||
|
|
** Adds N blank pages onto the end of DATABASE. N can be decimal
|
||
|
|
** or hex. The total number of pages after adding must be no greater
|
||
|
|
** than 4294967297
|
||
|
|
*/
|
||
|
|
#include <stdio.h>
|
||
|
|
#include <string.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
|
||
|
|
int main(int argc, char **argv){
|
||
|
|
char *zEnd;
|
||
|
|
long long int toAppend;
|
||
|
|
long long int currentSz;
|
||
|
|
long long int newSz;
|
||
|
|
FILE *f;
|
||
|
|
size_t got;
|
||
|
|
int pgsz;
|
||
|
|
char zero = 0;
|
||
|
|
unsigned char buf[100];
|
||
|
|
|
||
|
|
if( argc!=3 ) goto usage_error;
|
||
|
|
toAppend = strtoll(argv[2], &zEnd, 0);
|
||
|
|
if( zEnd==argv[2] || zEnd[0] ) goto usage_error;
|
||
|
|
if( toAppend<1 ){
|
||
|
|
fprintf(stderr, "N must be at least 1\n");
|
||
|
|
exit(1);
|
||
|
|
}
|
||
|
|
f = fopen(argv[1], "r+b");
|
||
|
|
if( f==0 ){
|
||
|
|
fprintf(stderr, "cannot open \"%s\" for reading and writing\n", argv[1]);
|
||
|
|
exit(1);
|
||
|
|
}
|
||
|
|
got = fread(buf, 1, sizeof(buf), f);
|
||
|
|
if( got!=sizeof(buf) ) goto not_valid_db;
|
||
|
|
if( strcmp((char*)buf,"SQLite format 3")!=0 ) goto not_valid_db;
|
||
|
|
pgsz = (buf[16]<<8) + buf[17];
|
||
|
|
if( pgsz==1 ) pgsz = 65536;
|
||
|
|
if( pgsz<512 || pgsz>65536 || (pgsz&(pgsz-1))!=0 ) goto not_valid_db;
|
||
|
|
currentSz = (buf[28]<<24) + (buf[29]<<16) + (buf[30]<<8) + buf[31];
|
||
|
|
newSz = currentSz + toAppend;
|
||
|
|
if( newSz > 0xffffffff ) newSz = 0xffffffff;
|
||
|
|
buf[28] = (newSz>>24) & 0xff;
|
||
|
|
buf[29] = (newSz>>16) & 0xff;
|
||
|
|
buf[30] = (newSz>>8) & 0xff;
|
||
|
|
buf[31] = newSz & 0xff;
|
||
|
|
fseek(f, 28, SEEK_SET);
|
||
|
|
fwrite(&buf[28],4,1,f);
|
||
|
|
fseek(f, (long)(newSz*pgsz - 1), SEEK_SET);
|
||
|
|
fwrite(&zero,1,1,f);
|
||
|
|
fclose(f);
|
||
|
|
return 0;
|
||
|
|
|
||
|
|
not_valid_db:
|
||
|
|
fprintf(stderr,"not a valid database: %s\n", argv[1]);
|
||
|
|
exit(1);
|
||
|
|
|
||
|
|
usage_error:
|
||
|
|
fprintf(stderr,"Usage: %s DATABASE N\n", argv[0]);
|
||
|
|
exit(1);
|
||
|
|
}
|