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fa68815fa326af4b9bcdc61df39185170985f078
sqlite/tool/showdb.c
drh 970ea372c4 Fix a problem in the "showdb" utility that prevents it from correctly 
decoding cells with no content beyond the record header.

FossilOrigin-Name: eb7680a1c047b2a33d6a0c9733fafaee11272377c627af10bbd541b6b7ed952b
2017-03-16 13:14:03 +00:00

1180 lines
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/*
** A utility for printing all or part of an SQLite database file.
*/
#include <stdio.h>
#include <ctype.h>
#define ISDIGIT(X) isdigit((unsigned char)(X))
#define ISPRINT(X) isprint((unsigned char)(X))
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#if !defined(_MSC_VER)
#include <unistd.h>
#else
#include <io.h>
#endif
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include "sqlite3.h"
static struct GlobalData {
int pagesize; /* Size of a database page */
int dbfd; /* File descriptor for reading the DB */
int mxPage; /* Last page number */
int perLine; /* HEX elements to print per line */
int bRaw; /* True to access db file via OS APIs */
sqlite3_file *pFd; /* File descriptor for non-raw mode */
sqlite3 *pDb; /* Database handle that owns pFd */
} g = {1024, -1, 0, 16, 0, 0, 0};
typedef long long int i64; /* Datatype for 64-bit integers */
/*
** Convert the var-int format into i64. Return the number of bytes
** in the var-int. Write the var-int value into *pVal.
*/
static int decodeVarint(const unsigned char *z, i64 *pVal){
i64 v = 0;
int i;
for(i=0; i<8; i++){
v = (v<<7) + (z[i]&0x7f);
if( (z[i]&0x80)==0 ){ *pVal = v; return i+1; }
}
v = (v<<8) + (z[i]&0xff);
*pVal = v;
return 9;
}
/*
** Extract a big-endian 32-bit integer
*/
static unsigned int decodeInt32(const unsigned char *z){
return (z[0]<<24) + (z[1]<<16) + (z[2]<<8) + z[3];
}
/* Report an out-of-memory error and die.
*/
static void out_of_memory(void){
fprintf(stderr,"Out of memory...\n");
exit(1);
}
/*
** Open a database connection.
*/
static sqlite3 *openDatabase(const char *zPrg, const char *zName){
sqlite3 *db = 0;
int flags = SQLITE_OPEN_READWRITE | SQLITE_OPEN_URI;
int rc = sqlite3_open_v2(zName, &db, flags, 0);
if( rc!=SQLITE_OK ){
const char *zErr = sqlite3_errmsg(db);
fprintf(stderr, "%s: can't open %s (%s)\n", zPrg, zName, zErr);
sqlite3_close(db);
exit(1);
}
return db;
}
/**************************************************************************
** Beginning of low-level file access functions.
**
** All low-level access to the database file read by this program is
** performed using the following four functions:
**
** fileOpen() - open the db file
** fileClose() - close the db file
** fileRead() - read raw data from the db file
** fileGetsize() - return the size of the db file in bytes
*/
/*
** Open the database file.
*/
static void fileOpen(const char *zPrg, const char *zName){
assert( g.dbfd<0 );
if( g.bRaw==0 ){
int rc;
void *pArg = (void *)(&g.pFd);
g.pDb = openDatabase(zPrg, zName);
rc = sqlite3_file_control(g.pDb, "main", SQLITE_FCNTL_FILE_POINTER, pArg);
if( rc!=SQLITE_OK ){
fprintf(stderr,
"%s: failed to obtain fd for %s (SQLite too old?)\n", zPrg, zName
);
exit(1);
}
}else{
g.dbfd = open(zName, O_RDONLY);
if( g.dbfd<0 ){
fprintf(stderr,"%s: can't open %s\n", zPrg, zName);
exit(1);
}
}
}
/*
** Close the database file opened by fileOpen()
*/
static void fileClose(){
if( g.bRaw==0 ){
sqlite3_close(g.pDb);
g.pDb = 0;
g.pFd = 0;
}else{
close(g.dbfd);
g.dbfd = -1;
}
}
/*
** Read content from the file.
**
** Space to hold the content is obtained from sqlite3_malloc() and needs
** to be freed by the caller.
*/
static unsigned char *fileRead(sqlite3_int64 ofst, int nByte){
unsigned char *aData;
int got;
aData = sqlite3_malloc(nByte+32);
if( aData==0 ) out_of_memory();
memset(aData, 0, nByte+32);
if( g.bRaw==0 ){
int rc = g.pFd->pMethods->xRead(g.pFd, (void*)aData, nByte, ofst);
if( rc!=SQLITE_OK && rc!=SQLITE_IOERR_SHORT_READ ){
fprintf(stderr, "error in xRead() - %d\n", rc);
exit(1);
}
}else{
lseek(g.dbfd, (long)ofst, SEEK_SET);
got = read(g.dbfd, aData, nByte);
if( got>0 && got<nByte ) memset(aData+got, 0, nByte-got);
}
return aData;
}
/*
** Return the size of the file in byte.
*/
static sqlite3_int64 fileGetsize(void){
sqlite3_int64 res = 0;
if( g.bRaw==0 ){
int rc = g.pFd->pMethods->xFileSize(g.pFd, &res);
if( rc!=SQLITE_OK ){
fprintf(stderr, "error in xFileSize() - %d\n", rc);
exit(1);
}
}else{
struct stat sbuf;
fstat(g.dbfd, &sbuf);
res = (sqlite3_int64)(sbuf.st_size);
}
return res;
}
/*
** End of low-level file access functions.
**************************************************************************/
/*
** Print a range of bytes as hex and as ascii.
*/
static unsigned char *print_byte_range(
int ofst, /* First byte in the range of bytes to print */
int nByte, /* Number of bytes to print */
int printOfst /* Add this amount to the index on the left column */
){
unsigned char *aData;
int i, j;
const char *zOfstFmt;
if( ((printOfst+nByte)&~0xfff)==0 ){
zOfstFmt = " %03x: ";
}else if( ((printOfst+nByte)&~0xffff)==0 ){
zOfstFmt = " %04x: ";
}else if( ((printOfst+nByte)&~0xfffff)==0 ){
zOfstFmt = " %05x: ";
}else if( ((printOfst+nByte)&~0xffffff)==0 ){
zOfstFmt = " %06x: ";
}else{
zOfstFmt = " %08x: ";
}
aData = fileRead(ofst, nByte);
for(i=0; i<nByte; i += g.perLine){
fprintf(stdout, zOfstFmt, i+printOfst);
for(j=0; j<g.perLine; j++){
if( i+j>nByte ){
fprintf(stdout, " ");
}else{
fprintf(stdout,"%02x ", aData[i+j]);
}
}
for(j=0; j<g.perLine; j++){
if( i+j>nByte ){
fprintf(stdout, " ");
}else{
fprintf(stdout,"%c", ISPRINT(aData[i+j]) ? aData[i+j] : '.');
}
}
fprintf(stdout,"\n");
}
return aData;
}
/*
** Print an entire page of content as hex
*/
static void print_page(int iPg){
int iStart;
unsigned char *aData;
iStart = (iPg-1)*g.pagesize;
fprintf(stdout, "Page %d: (offsets 0x%x..0x%x)\n",
iPg, iStart, iStart+g.pagesize-1);
aData = print_byte_range(iStart, g.pagesize, 0);
sqlite3_free(aData);
}
/* Print a line of decode output showing a 4-byte integer.
*/
static void print_decode_line(
unsigned char *aData, /* Content being decoded */
int ofst, int nByte, /* Start and size of decode */
const char *zMsg /* Message to append */
){
int i, j;
int val = aData[ofst];
char zBuf[100];
sprintf(zBuf, " %03x: %02x", ofst, aData[ofst]);
i = (int)strlen(zBuf);
for(j=1; j<4; j++){
if( j>=nByte ){
sprintf(&zBuf[i], " ");
}else{
sprintf(&zBuf[i], " %02x", aData[ofst+j]);
val = val*256 + aData[ofst+j];
}
i += (int)strlen(&zBuf[i]);
}
sprintf(&zBuf[i], " %9d", val);
printf("%s %s\n", zBuf, zMsg);
}
/*
** Decode the database header.
*/
static void print_db_header(void){
unsigned char *aData;
aData = print_byte_range(0, 100, 0);
printf("Decoded:\n");
print_decode_line(aData, 16, 2, "Database page size");
print_decode_line(aData, 18, 1, "File format write version");
print_decode_line(aData, 19, 1, "File format read version");
print_decode_line(aData, 20, 1, "Reserved space at end of page");
print_decode_line(aData, 24, 4, "File change counter");
print_decode_line(aData, 28, 4, "Size of database in pages");
print_decode_line(aData, 32, 4, "Page number of first freelist page");
print_decode_line(aData, 36, 4, "Number of freelist pages");
print_decode_line(aData, 40, 4, "Schema cookie");
print_decode_line(aData, 44, 4, "Schema format version");
print_decode_line(aData, 48, 4, "Default page cache size");
print_decode_line(aData, 52, 4, "Largest auto-vac root page");
print_decode_line(aData, 56, 4, "Text encoding");
print_decode_line(aData, 60, 4, "User version");
print_decode_line(aData, 64, 4, "Incremental-vacuum mode");
print_decode_line(aData, 68, 4, "Application ID");
print_decode_line(aData, 72, 4, "meta[8]");
print_decode_line(aData, 76, 4, "meta[9]");
print_decode_line(aData, 80, 4, "meta[10]");
print_decode_line(aData, 84, 4, "meta[11]");
print_decode_line(aData, 88, 4, "meta[12]");
print_decode_line(aData, 92, 4, "Change counter for version number");
print_decode_line(aData, 96, 4, "SQLite version number");
}
/*
** Describe cell content.
*/
static i64 describeContent(
unsigned char *a, /* Cell content */
i64 nLocal, /* Bytes in a[] */
char *zDesc /* Write description here */
){
i64 nDesc = 0;
int n, j;
i64 i, x, v;
const unsigned char *pData;
const unsigned char *pLimit;
char sep = ' ';
pLimit = &a[nLocal];
n = decodeVarint(a, &x);
pData = &a[x];
a += n;
i = x - n;
while( i>0 && pData<=pLimit ){
n = decodeVarint(a, &x);
a += n;
i -= n;
nLocal -= n;
zDesc[0] = sep;
sep = ',';
nDesc++;
zDesc++;
if( x==0 ){
sprintf(zDesc, "*"); /* NULL is a "*" */
}else if( x>=1 && x<=6 ){
v = (signed char)pData[0];
pData++;
switch( x ){
case 6: v = (v<<16) + (pData[0]<<8) + pData[1]; pData += 2;
case 5: v = (v<<16) + (pData[0]<<8) + pData[1]; pData += 2;
case 4: v = (v<<8) + pData[0]; pData++;
case 3: v = (v<<8) + pData[0]; pData++;
case 2: v = (v<<8) + pData[0]; pData++;
}
sprintf(zDesc, "%lld", v);
}else if( x==7 ){
sprintf(zDesc, "real");
pData += 8;
}else if( x==8 ){
sprintf(zDesc, "0");
}else if( x==9 ){
sprintf(zDesc, "1");
}else if( x>=12 ){
i64 size = (x-12)/2;
if( (x&1)==0 ){
sprintf(zDesc, "blob(%lld)", size);
}else{
sprintf(zDesc, "txt(%lld)", size);
}
pData += size;
}
j = (int)strlen(zDesc);
zDesc += j;
nDesc += j;
}
return nDesc;
}
/*
** Compute the local payload size given the total payload size and
** the page size.
*/
static i64 localPayload(i64 nPayload, char cType){
i64 maxLocal;
i64 minLocal;
i64 surplus;
i64 nLocal;
if( cType==13 ){
/* Table leaf */
maxLocal = g.pagesize-35;
minLocal = (g.pagesize-12)*32/255-23;
}else{
maxLocal = (g.pagesize-12)*64/255-23;
minLocal = (g.pagesize-12)*32/255-23;
}
if( nPayload>maxLocal ){
surplus = minLocal + (nPayload-minLocal)%(g.pagesize-4);
if( surplus<=maxLocal ){
nLocal = surplus;
}else{
nLocal = minLocal;
}
}else{
nLocal = nPayload;
}
return nLocal;
}
/*
** Create a description for a single cell.
**
** The return value is the local cell size.
*/
static i64 describeCell(
unsigned char cType, /* Page type */
unsigned char *a, /* Cell content */
int showCellContent, /* Show cell content if true */
char **pzDesc /* Store description here */
){
int i;
i64 nDesc = 0;
int n = 0;
int leftChild;
i64 nPayload;
i64 rowid;
i64 nLocal;
static char zDesc[1000];
i = 0;
if( cType<=5 ){
leftChild = ((a[0]*256 + a[1])*256 + a[2])*256 + a[3];
a += 4;
n += 4;
sprintf(zDesc, "lx: %d ", leftChild);
nDesc = strlen(zDesc);
}
if( cType!=5 ){
i = decodeVarint(a, &nPayload);
a += i;
n += i;
sprintf(&zDesc[nDesc], "n: %lld ", nPayload);
nDesc += strlen(&zDesc[nDesc]);
nLocal = localPayload(nPayload, cType);
}else{
nPayload = nLocal = 0;
}
if( cType==5 || cType==13 ){
i = decodeVarint(a, &rowid);
a += i;
n += i;
sprintf(&zDesc[nDesc], "r: %lld ", rowid);
nDesc += strlen(&zDesc[nDesc]);
}
if( nLocal<nPayload ){
int ovfl;
unsigned char *b = &a[nLocal];
ovfl = ((b[0]*256 + b[1])*256 + b[2])*256 + b[3];
sprintf(&zDesc[nDesc], "ov: %d ", ovfl);
nDesc += strlen(&zDesc[nDesc]);
n += 4;
}
if( showCellContent && cType!=5 ){
nDesc += describeContent(a, nLocal, &zDesc[nDesc-1]);
}
*pzDesc = zDesc;
return nLocal+n;
}
/* Print an offset followed by nByte bytes. Add extra white-space
** at the end so that subsequent text is aligned.
*/
static void printBytes(
unsigned char *aData, /* Content being decoded */
unsigned char *aStart, /* Start of content to be printed */
int nByte /* Number of bytes to print */
){
int j;
printf(" %03x: ", (int)(aStart-aData));
for(j=0; j<9; j++){
if( j>=nByte ){
printf(" ");
}else{
printf("%02x ", aStart[j]);
}
}
}
/*
** Write a full decode on stdout for the cell at a[ofst].
** Assume the page contains a header of size szPgHdr bytes.
*/
static void decodeCell(
unsigned char *a, /* Page content (without the page-1 header) */
unsigned pgno, /* Page number */
int iCell, /* Cell index */
int szPgHdr, /* Size of the page header. 0 or 100 */
int ofst /* Cell begins at a[ofst] */
){
int i, j = 0;
int leftChild;
i64 k;
i64 nPayload;
i64 rowid;
i64 nHdr;
i64 iType;
i64 nLocal;
unsigned char *x = a + ofst;
unsigned char *end;
unsigned char cType = a[0];
int nCol = 0;
int szCol[2000];
int ofstCol[2000];
int typeCol[2000];
printf("Cell[%d]:\n", iCell);
if( cType<=5 ){
leftChild = ((x[0]*256 + x[1])*256 + x[2])*256 + x[3];
printBytes(a, x, 4);
printf("left child page:: %d\n", leftChild);
x += 4;
}
if( cType!=5 ){
i = decodeVarint(x, &nPayload);
printBytes(a, x, i);
nLocal = localPayload(nPayload, cType);
if( nLocal==nPayload ){
printf("payload-size: %lld\n", nPayload);
}else{
printf("payload-size: %lld (%lld local, %lld overflow)\n",
nPayload, nLocal, nPayload-nLocal);
}
x += i;
}else{
nPayload = nLocal = 0;
}
end = x + nLocal;
if( cType==5 || cType==13 ){
i = decodeVarint(x, &rowid);
printBytes(a, x, i);
printf("rowid: %lld\n", rowid);
x += i;
}
if( nLocal>0 ){
i = decodeVarint(x, &nHdr);
printBytes(a, x, i);
printf("record-header-size: %d\n", (int)nHdr);
j = i;
nCol = 0;
k = nHdr;
while( x+j<=end && j<nHdr ){
const char *zTypeName;
int sz = 0;
char zNm[30];
i = decodeVarint(x+j, &iType);
printBytes(a, x+j, i);
printf("typecode[%d]: %d - ", nCol, (int)iType);
switch( iType ){
case 0: zTypeName = "NULL"; sz = 0; break;
case 1: zTypeName = "int8"; sz = 1; break;
case 2: zTypeName = "int16"; sz = 2; break;
case 3: zTypeName = "int24"; sz = 3; break;
case 4: zTypeName = "int32"; sz = 4; break;
case 5: zTypeName = "int48"; sz = 6; break;
case 6: zTypeName = "int64"; sz = 8; break;
case 7: zTypeName = "double"; sz = 8; break;
case 8: zTypeName = "zero"; sz = 0; break;
case 9: zTypeName = "one"; sz = 0; break;
case 10:
case 11: zTypeName = "error"; sz = 0; break;
default: {
sz = (int)(iType-12)/2;
sprintf(zNm, (iType&1)==0 ? "blob(%d)" : "text(%d)", sz);
zTypeName = zNm;
break;
}
}
printf("%s\n", zTypeName);
szCol[nCol] = sz;
ofstCol[nCol] = (int)k;
typeCol[nCol] = (int)iType;
k += sz;
nCol++;
j += i;
}
for(i=0; i<nCol && ofstCol[i]+szCol[i]<=nLocal; i++){
int s = ofstCol[i];
i64 v;
const unsigned char *pData;
if( szCol[i]==0 ) continue;
printBytes(a, x+s, szCol[i]);
printf("data[%d]: ", i);
pData = x+s;
if( typeCol[i]<=7 ){
v = (signed char)pData[0];
for(k=1; k<szCol[i]; k++){
v = (v<<8) + pData[k];
}
if( typeCol[i]==7 ){
double r;
memcpy(&r, &v, sizeof(r));
printf("%#g\n", r);
}else{
printf("%lld\n", v);
}
}else{
int ii, jj;
char zConst[32];
if( (typeCol[i]&1)==0 ){
zConst[0] = 'x';
zConst[1] = '\'';
for(ii=2, jj=0; jj<szCol[i] && ii<24; jj++, ii+=2){
sprintf(zConst+ii, "%02x", pData[jj]);
}
}else{
zConst[0] = '\'';
for(ii=1, jj=0; jj<szCol[i] && ii<24; jj++, ii++){
zConst[ii] = ISPRINT(pData[jj]) ? pData[jj] : '.';
}
zConst[ii] = 0;
}
if( jj<szCol[i] ){
memcpy(zConst+ii, "...'", 5);
}else{
memcpy(zConst+ii, "'", 2);
}
printf("%s\n", zConst);
}
j = ofstCol[i] + szCol[i];
}
}
if( j<nLocal ){
printBytes(a, x+j, 0);
printf("... %lld bytes of content ...\n", nLocal-j);
}
if( nLocal<nPayload ){
printBytes(a, x+nLocal, 4);
printf("overflow-page: %d\n", decodeInt32(x+nLocal));
}
}
/*
** Decode a btree page
*/
static void decode_btree_page(
unsigned char *a, /* Page content */
int pgno, /* Page number */
int hdrSize, /* Size of the page header. 0 or 100 */
char *zArgs /* Flags to control formatting */
){
const char *zType = "unknown";
int nCell;
int i, j;
int iCellPtr;
int showCellContent = 0;
int showMap = 0;
int cellToDecode = -2;
char *zMap = 0;
switch( a[0] ){
case 2: zType = "index interior node"; break;
case 5: zType = "table interior node"; break;
case 10: zType = "index leaf"; break;
case 13: zType = "table leaf"; break;
}
while( zArgs[0] ){
switch( zArgs[0] ){
case 'c': showCellContent = 1; break;
case 'm': showMap = 1; break;
case 'd': {
if( !ISDIGIT(zArgs[1]) ){
cellToDecode = -1;
}else{
cellToDecode = 0;
while( ISDIGIT(zArgs[1]) ){
zArgs++;
cellToDecode = cellToDecode*10 + zArgs[0] - '0';
}
}
break;
}
}
zArgs++;
}
nCell = a[3]*256 + a[4];
iCellPtr = (a[0]==2 || a[0]==5) ? 12 : 8;
if( cellToDecode>=nCell ){
printf("Page %d has only %d cells\n", pgno, nCell);
return;
}
printf("Header on btree page %d:\n", pgno);
print_decode_line(a, 0, 1, zType);
print_decode_line(a, 1, 2, "Offset to first freeblock");
print_decode_line(a, 3, 2, "Number of cells on this page");
print_decode_line(a, 5, 2, "Offset to cell content area");
print_decode_line(a, 7, 1, "Fragmented byte count");
if( a[0]==2 || a[0]==5 ){
print_decode_line(a, 8, 4, "Right child");
}
if( cellToDecode==(-2) && nCell>0 ){
printf(" key: lx=left-child n=payload-size r=rowid\n");
}
if( showMap ){
zMap = sqlite3_malloc(g.pagesize);
memset(zMap, '.', g.pagesize);
memset(zMap, '1', hdrSize);
memset(&zMap[hdrSize], 'H', iCellPtr);
memset(&zMap[hdrSize+iCellPtr], 'P', 2*nCell);
}
for(i=0; i<nCell; i++){
int cofst = iCellPtr + i*2;
char *zDesc;
i64 n;
cofst = a[cofst]*256 + a[cofst+1];
n = describeCell(a[0], &a[cofst-hdrSize], showCellContent, &zDesc);
if( showMap ){
char zBuf[30];
memset(&zMap[cofst], '*', (size_t)n);
zMap[cofst] = '[';
zMap[cofst+n-1] = ']';
sprintf(zBuf, "%d", i);
j = (int)strlen(zBuf);
if( j<=n-2 ) memcpy(&zMap[cofst+1], zBuf, j);
}
if( cellToDecode==(-2) ){
printf(" %03x: cell[%d] %s\n", cofst, i, zDesc);
}else if( cellToDecode==(-1) || cellToDecode==i ){
decodeCell(a, pgno, i, hdrSize, cofst-hdrSize);
}
}
if( showMap ){
printf("Page map: (H=header P=cell-index 1=page-1-header .=free-space)\n");
for(i=0; i<g.pagesize; i+=64){
printf(" %03x: %.64s\n", i, &zMap[i]);
}
sqlite3_free(zMap);
}
}
/*
** Decode a freelist trunk page.
*/
static void decode_trunk_page(
int pgno, /* The page number */
int detail, /* Show leaf pages if true */
int recursive /* Follow the trunk change if true */
){
int n, i;
unsigned char *a;
while( pgno>0 ){
a = fileRead((pgno-1)*g.pagesize, g.pagesize);
printf("Decode of freelist trunk page %d:\n", pgno);
print_decode_line(a, 0, 4, "Next freelist trunk page");
print_decode_line(a, 4, 4, "Number of entries on this page");
if( detail ){
n = (int)decodeInt32(&a[4]);
for(i=0; i<n; i++){
unsigned int x = decodeInt32(&a[8+4*i]);
char zIdx[10];
sprintf(zIdx, "[%d]", i);
printf(" %5s %7u", zIdx, x);
if( i%5==4 ) printf("\n");
}
if( i%5!=0 ) printf("\n");
}
if( !recursive ){
pgno = 0;
}else{
pgno = (int)decodeInt32(&a[0]);
}
sqlite3_free(a);
}
}
/*
** A short text comment on the use of each page.
*/
static char **zPageUse;
/*
** Add a comment on the use of a page.
*/
static void page_usage_msg(int pgno, const char *zFormat, ...){
va_list ap;
char *zMsg;
va_start(ap, zFormat);
zMsg = sqlite3_vmprintf(zFormat, ap);
va_end(ap);
if( pgno<=0 || pgno>g.mxPage ){
printf("ERROR: page %d out of range 1..%d: %s\n",
pgno, g.mxPage, zMsg);
sqlite3_free(zMsg);
return;
}
if( zPageUse[pgno]!=0 ){
printf("ERROR: page %d used multiple times:\n", pgno);
printf("ERROR: previous: %s\n", zPageUse[pgno]);
printf("ERROR: current: %s\n", zMsg);
sqlite3_free(zPageUse[pgno]);
}
zPageUse[pgno] = zMsg;
}
/*
** Find overflow pages of a cell and describe their usage.
*/
static void page_usage_cell(
unsigned char cType, /* Page type */
unsigned char *a, /* Cell content */
int pgno, /* page containing the cell */
int cellno /* Index of the cell on the page */
){
int i;
int n = 0;
i64 nPayload;
i64 rowid;
i64 nLocal;
i = 0;
if( cType<=5 ){
a += 4;
n += 4;
}
if( cType!=5 ){
i = decodeVarint(a, &nPayload);
a += i;
n += i;
nLocal = localPayload(nPayload, cType);
}else{
nPayload = nLocal = 0;
}
if( cType==5 || cType==13 ){
i = decodeVarint(a, &rowid);
a += i;
n += i;
}
if( nLocal<nPayload ){
int ovfl = decodeInt32(a+nLocal);
int cnt = 0;
while( ovfl && (cnt++)<g.mxPage ){
page_usage_msg(ovfl, "overflow %d from cell %d of page %d",
cnt, cellno, pgno);
a = fileRead((ovfl-1)*g.pagesize, 4);
ovfl = decodeInt32(a);
sqlite3_free(a);
}
}
}
/*
** Describe the usages of a b-tree page
*/
static void page_usage_btree(
int pgno, /* Page to describe */
int parent, /* Parent of this page. 0 for root pages */
int idx, /* Which child of the parent */
const char *zName /* Name of the table */
){
unsigned char *a;
const char *zType = "corrupt node";
int nCell;
int i;
int hdr = pgno==1 ? 100 : 0;
if( pgno<=0 || pgno>g.mxPage ) return;
a = fileRead((pgno-1)*g.pagesize, g.pagesize);
switch( a[hdr] ){
case 2: zType = "interior node of index"; break;
case 5: zType = "interior node of table"; break;
case 10: zType = "leaf of index"; break;
case 13: zType = "leaf of table"; break;
}
if( parent ){
page_usage_msg(pgno, "%s [%s], child %d of page %d",
zType, zName, idx, parent);
}else{
page_usage_msg(pgno, "root %s [%s]", zType, zName);
}
nCell = a[hdr+3]*256 + a[hdr+4];
if( a[hdr]==2 || a[hdr]==5 ){
int cellstart = hdr+12;
unsigned int child;
for(i=0; i<nCell; i++){
int ofst;
ofst = cellstart + i*2;
ofst = a[ofst]*256 + a[ofst+1];
child = decodeInt32(a+ofst);
page_usage_btree(child, pgno, i, zName);
}
child = decodeInt32(a+cellstart-4);
page_usage_btree(child, pgno, i, zName);
}
if( a[hdr]==2 || a[hdr]==10 || a[hdr]==13 ){
int cellstart = hdr + 8 + 4*(a[hdr]<=5);
for(i=0; i<nCell; i++){
int ofst;
ofst = cellstart + i*2;
ofst = a[ofst]*256 + a[ofst+1];
page_usage_cell(a[hdr], a+ofst, pgno, i);
}
}
sqlite3_free(a);
}
/*
** Determine page usage by the freelist
*/
static void page_usage_freelist(int pgno){
unsigned char *a;
int cnt = 0;
int i;
int n;
int iNext;
int parent = 1;
while( pgno>0 && pgno<=g.mxPage && (cnt++)<g.mxPage ){
page_usage_msg(pgno, "freelist trunk #%d child of %d", cnt, parent);
a = fileRead((pgno-1)*g.pagesize, g.pagesize);
iNext = decodeInt32(a);
n = decodeInt32(a+4);
for(i=0; i<n; i++){
int child = decodeInt32(a + (i*4+8));
page_usage_msg(child, "freelist leaf, child %d of trunk page %d",
i, pgno);
}
sqlite3_free(a);
parent = pgno;
pgno = iNext;
}
}
/*
** Determine pages used as PTRMAP pages
*/
static void page_usage_ptrmap(unsigned char *a){
if( a[55] ){
int usable = g.pagesize - a[20];
int pgno = 2;
int perPage = usable/5;
while( pgno<=g.mxPage ){
page_usage_msg(pgno, "PTRMAP page covering %d..%d",
pgno+1, pgno+perPage);
pgno += perPage + 1;
}
}
}
/*
** Try to figure out how every page in the database file is being used.
*/
static void page_usage_report(const char *zPrg, const char *zDbName){
int i, j;
int rc;
sqlite3 *db;
sqlite3_stmt *pStmt;
unsigned char *a;
char zQuery[200];
/* Avoid the pathological case */
if( g.mxPage<1 ){
printf("empty database\n");
return;
}
/* Open the database file */
db = openDatabase(zPrg, zDbName);
/* Set up global variables zPageUse[] and g.mxPage to record page
** usages */
zPageUse = sqlite3_malloc( sizeof(zPageUse[0])*(g.mxPage+1) );
if( zPageUse==0 ) out_of_memory();
memset(zPageUse, 0, sizeof(zPageUse[0])*(g.mxPage+1));
/* Discover the usage of each page */
a = fileRead(0, 100);
page_usage_freelist(decodeInt32(a+32));
page_usage_ptrmap(a);
sqlite3_free(a);
page_usage_btree(1, 0, 0, "sqlite_master");
sqlite3_exec(db, "PRAGMA writable_schema=ON", 0, 0, 0);
for(j=0; j<2; j++){
sqlite3_snprintf(sizeof(zQuery), zQuery,
"SELECT type, name, rootpage FROM SQLITE_MASTER WHERE rootpage"
" ORDER BY rowid %s", j?"DESC":"");
rc = sqlite3_prepare_v2(db, zQuery, -1, &pStmt, 0);
if( rc==SQLITE_OK ){
while( sqlite3_step(pStmt)==SQLITE_ROW ){
int pgno = sqlite3_column_int(pStmt, 2);
page_usage_btree(pgno, 0, 0, (const char*)sqlite3_column_text(pStmt,1));
}
}else{
printf("ERROR: cannot query database: %s\n", sqlite3_errmsg(db));
}
rc = sqlite3_finalize(pStmt);
if( rc==SQLITE_OK ) break;
}
sqlite3_close(db);
/* Print the report and free memory used */
for(i=1; i<=g.mxPage; i++){
printf("%5d: %s\n", i, zPageUse[i] ? zPageUse[i] : "???");
sqlite3_free(zPageUse[i]);
}
sqlite3_free(zPageUse);
zPageUse = 0;
}
/*
** Try to figure out how every page in the database file is being used.
*/
static void ptrmap_coverage_report(const char *zDbName){
int pgno;
unsigned char *aHdr;
unsigned char *a;
int usable;
int perPage;
int i;
/* Avoid the pathological case */
if( g.mxPage<1 ){
printf("empty database\n");
return;
}
/* Make sure PTRMAPs are used in this database */
aHdr = fileRead(0, 100);
if( aHdr[55]==0 ){
printf("database does not use PTRMAP pages\n");
return;
}
usable = g.pagesize - aHdr[20];
perPage = usable/5;
sqlite3_free(aHdr);
printf("%5d: root of sqlite_master\n", 1);
for(pgno=2; pgno<=g.mxPage; pgno += perPage+1){
printf("%5d: PTRMAP page covering %d..%d\n", pgno,
pgno+1, pgno+perPage);
a = fileRead((pgno-1)*g.pagesize, usable);
for(i=0; i+5<=usable && pgno+1+i/5<=g.mxPage; i+=5){
const char *zType = "???";
unsigned int iFrom = decodeInt32(&a[i+1]);
switch( a[i] ){
case 1: zType = "b-tree root page"; break;
case 2: zType = "freelist page"; break;
case 3: zType = "first page of overflow"; break;
case 4: zType = "later page of overflow"; break;
case 5: zType = "b-tree non-root page"; break;
}
printf("%5d: %s, parent=%u\n", pgno+1+i/5, zType, iFrom);
}
sqlite3_free(a);
}
}
/*
** Print a usage comment
*/
static void usage(const char *argv0){
fprintf(stderr, "Usage %s ?--uri? FILENAME ?args...?\n\n", argv0);
fprintf(stderr,
"switches:\n"
" --raw Read db file directly, bypassing SQLite VFS\n"
"args:\n"
" dbheader Show database header\n"
" pgidx Index of how each page is used\n"
" ptrmap Show all PTRMAP page content\n"
" NNN..MMM Show hex of pages NNN through MMM\n"
" NNN..end Show hex of pages NNN through end of file\n"
" NNNb Decode btree page NNN\n"
" NNNbc Decode btree page NNN and show content\n"
" NNNbm Decode btree page NNN and show a layout map\n"
" NNNbdCCC Decode cell CCC on btree page NNN\n"
" NNNt Decode freelist trunk page NNN\n"
" NNNtd Show leaf freelist pages on the decode\n"
" NNNtr Recursively decode freelist starting at NNN\n"
);
}
int main(int argc, char **argv){
sqlite3_int64 szFile;
unsigned char *zPgSz;
const char *zPrg = argv[0]; /* Name of this executable */
char **azArg = argv;
int nArg = argc;
/* Check for the "--uri" or "-uri" switch. */
if( nArg>1 ){
if( sqlite3_stricmp("-raw", azArg[1])==0
|| sqlite3_stricmp("--raw", azArg[1])==0
){
g.bRaw = 1;
azArg++;
nArg--;
}
}
if( nArg<2 ){
usage(zPrg);
exit(1);
}
fileOpen(zPrg, azArg[1]);
szFile = fileGetsize();
zPgSz = fileRead(16, 2);
g.pagesize = zPgSz[0]*256 + zPgSz[1]*65536;
if( g.pagesize==0 ) g.pagesize = 1024;
sqlite3_free(zPgSz);
printf("Pagesize: %d\n", g.pagesize);
g.mxPage = (int)((szFile+g.pagesize-1)/g.pagesize);
printf("Available pages: 1..%d\n", g.mxPage);
if( nArg==2 ){
int i;
for(i=1; i<=g.mxPage; i++) print_page(i);
}else{
int i;
for(i=2; i<nArg; i++){
int iStart, iEnd;
char *zLeft;
if( strcmp(azArg[i], "dbheader")==0 ){
print_db_header();
continue;
}
if( strcmp(azArg[i], "pgidx")==0 ){
page_usage_report(zPrg, azArg[1]);
continue;
}
if( strcmp(azArg[i], "ptrmap")==0 ){
ptrmap_coverage_report(azArg[1]);
continue;
}
if( strcmp(azArg[i], "help")==0 ){
usage(zPrg);
continue;
}
if( !ISDIGIT(azArg[i][0]) ){
fprintf(stderr, "%s: unknown option: [%s]\n", zPrg, azArg[i]);
continue;
}
iStart = strtol(azArg[i], &zLeft, 0);
if( zLeft && strcmp(zLeft,"..end")==0 ){
iEnd = g.mxPage;
}else if( zLeft && zLeft[0]=='.' && zLeft[1]=='.' ){
iEnd = strtol(&zLeft[2], 0, 0);
}else if( zLeft && zLeft[0]=='b' ){
int ofst, nByte, hdrSize;
unsigned char *a;
if( iStart==1 ){
ofst = hdrSize = 100;
nByte = g.pagesize-100;
}else{
hdrSize = 0;
ofst = (iStart-1)*g.pagesize;
nByte = g.pagesize;
}
a = fileRead(ofst, nByte);
decode_btree_page(a, iStart, hdrSize, &zLeft[1]);
sqlite3_free(a);
continue;
}else if( zLeft && zLeft[0]=='t' ){
int detail = 0;
int recursive = 0;
int j;
for(j=1; zLeft[j]; j++){
if( zLeft[j]=='r' ) recursive = 1;
if( zLeft[j]=='d' ) detail = 1;
}
decode_trunk_page(iStart, detail, recursive);
continue;
}else{
iEnd = iStart;
}
if( iStart<1 || iEnd<iStart || iEnd>g.mxPage ){
fprintf(stderr,
"Page argument should be LOWER?..UPPER?. Range 1 to %d\n",
g.mxPage);
exit(1);
}
while( iStart<=iEnd ){
print_page(iStart);
iStart++;
}
}
}
fileClose();
return 0;
}
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