[sql] Import reference version of SQLite 3.17..

third_party/sqlite/sqlite-src-3170000/tool/showwal.c

+/*
+** A utility for printing content from a write-ahead log file.
+*/
+#include <stdio.h>
+#include <ctype.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#define ISDIGIT(X)  isdigit((unsigned char)(X))
+#define ISPRINT(X)  isprint((unsigned char)(X))
+
+#if !defined(_MSC_VER)
+#include <unistd.h>
+#else
+#include <io.h>
+#endif
+
+#include <stdlib.h>
+#include <string.h>
+
+
+static int pagesize = 1024;     /* Size of a database page */
+static int fd = -1;             /* File descriptor for reading the WAL file */
+static int mxFrame = 0;         /* Last frame */
+static int perLine = 16;        /* HEX elements to print per line */
+
+typedef long long int i64;      /* Datatype for 64-bit integers */
+
+/* Information for computing the checksum */
+typedef struct Cksum Cksum;
+struct Cksum {
+  int bSwap;           /* True to do byte swapping on 32-bit words */
+  unsigned s0, s1;     /* Current checksum value */
+};
+
+/*
+** extract a 32-bit big-endian integer
+*/
+static unsigned int getInt32(const unsigned char *a){
+  unsigned int x = (a[0]<<24) + (a[1]<<16) + (a[2]<<8) + a[3];
+  return x;
+}
+
+/*
+** Swap bytes on a 32-bit unsigned integer
+*/
+static unsigned int swab32(unsigned int x){
+  return (((x)&0x000000FF)<<24) + (((x)&0x0000FF00)<<8)
+         + (((x)&0x00FF0000)>>8)  + (((x)&0xFF000000)>>24);
+}
+
+/* Extend the checksum.  Reinitialize the checksum if bInit is true.
+*/
+static void extendCksum(
+  Cksum *pCksum,
+  unsigned char *aData,
+  unsigned int nByte,
+  int bInit
+){
+  unsigned int *a32;
+  if( bInit ){
+    int a = 0;
+    *((char*)&a) = 1;
+    if( a==1 ){
+      /* Host is little-endian */
+      pCksum->bSwap = getInt32(aData)!=0x377f0682;
+    }else{
+      /* Host is big-endian */
+      pCksum->bSwap = getInt32(aData)!=0x377f0683;
+    }
+    pCksum->s0 = 0;
+    pCksum->s1 = 0;
+  }
+  a32 = (unsigned int*)aData;
+  while( nByte>0 ){
+    unsigned int x0 = a32[0];
+    unsigned int x1 = a32[1];
+    if( pCksum->bSwap ){
+      x0 = swab32(x0);
+      x1 = swab32(x1);
+    }
+    pCksum->s0 += x0 + pCksum->s1;
+    pCksum->s1 += x1 + pCksum->s0;
+    nByte -= 8;
+    a32 += 2;
+  }
+}
+
+/*
+** 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;
+}
+
+/* Report an out-of-memory error and die.
+*/
+static void out_of_memory(void){
+  fprintf(stderr,"Out of memory...\n");
+  exit(1);
+}
+
+/*
+** Read content from the file.
+**
+** Space to hold the content is obtained from malloc() and needs to be
+** freed by the caller.
+*/
+static unsigned char *getContent(int ofst, int nByte){
+  unsigned char *aData;
+  aData = malloc(nByte);
+  if( aData==0 ) out_of_memory();
+  lseek(fd, ofst, SEEK_SET);
+  read(fd, aData, nByte);
+  return aData;
+}
+
+/*
+** Print a range of bytes as hex and as ascii.
+*/
+static void print_byte_range(
+  int ofst,              /* First byte in the range of bytes to print */
+  int nByte,             /* Number of bytes to print */
+  unsigned char *aData,  /* Content to print */
+  int printOfst          /* Add this amount to the index on the left column */
+){
+  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: ";
+  }
+
+  for(i=0; i<nByte; i += perLine){
+    fprintf(stdout, zOfstFmt, i+printOfst);
+    for(j=0; j<perLine; j++){
+      if( i+j>nByte ){
+        fprintf(stdout, "   ");
+      }else{
+        fprintf(stdout,"%02x ", aData[i+j]);
+      }
+    }
+    for(j=0; j<perLine; j++){
+      if( i+j>nByte ){
+        fprintf(stdout, " ");
+      }else{
+        fprintf(stdout,"%c", ISPRINT(aData[i+j]) ? aData[i+j] : '.');
+      }
+    }
+    fprintf(stdout,"\n");
+  }
+}
+
+/* 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 */
+  int asHex,                 /* If true, output value as hex */
+  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]);
+  }
+  if( asHex ){
+    sprintf(&zBuf[i], "  0x%08x", val);
+  }else{
+    sprintf(&zBuf[i], "   %9d", val);
+  }
+  printf("%s  %s\n", zBuf, zMsg);
+}
+
+/*
+** Print an entire page of content as hex
+*/
+static void print_frame(int iFrame){
+  int iStart;
+  unsigned char *aData;
+  iStart = 32 + (iFrame-1)*(pagesize+24);
+  fprintf(stdout, "Frame %d:   (offsets 0x%x..0x%x)\n",
+          iFrame, iStart, iStart+pagesize+24);
+  aData = getContent(iStart, pagesize+24);
+  print_decode_line(aData, 0, 4, 0, "Page number");
+  print_decode_line(aData, 4, 4, 0, "DB size, or 0 for non-commit");
+  print_decode_line(aData, 8, 4, 1, "Salt-1");
+  print_decode_line(aData,12, 4, 1, "Salt-2");
+  print_decode_line(aData,16, 4, 1, "Checksum-1");
+  print_decode_line(aData,20, 4, 1, "Checksum-2");
+  print_byte_range(iStart+24, pagesize, aData+24, 0);
+  free(aData);
+}
+
+/*
+** Summarize a single frame on a single line.
+*/
+static void print_oneline_frame(int iFrame, Cksum *pCksum){
+  int iStart;
+  unsigned char *aData;
+  unsigned int s0, s1;
+  iStart = 32 + (iFrame-1)*(pagesize+24);
+  aData = getContent(iStart, 24);
+  extendCksum(pCksum, aData, 8, 0);
+  extendCksum(pCksum, getContent(iStart+24, pagesize), pagesize, 0);
+  s0 = getInt32(aData+16);
+  s1 = getInt32(aData+20);
+  fprintf(stdout, "Frame %4d: %6d %6d 0x%08x,%08x 0x%08x,%08x %s\n",
+          iFrame, 
+          getInt32(aData),
+          getInt32(aData+4),
+          getInt32(aData+8),
+          getInt32(aData+12),
+          s0,
+          s1,
+          (s0==pCksum->s0 && s1==pCksum->s1) ? "" : "cksum-fail"
+  );
+
+  /* Reset the checksum so that a single frame checksum failure will not
+  ** cause all subsequent frames to also show a failure. */
+  pCksum->s0 = s0;
+  pCksum->s1 = s1;
+  free(aData);
+}
+
+/*
+** Decode the WAL header.
+*/
+static void print_wal_header(Cksum *pCksum){
+  unsigned char *aData;
+  aData = getContent(0, 32);
+  if( pCksum ){
+    extendCksum(pCksum, aData, 24, 1);
+    printf("Checksum byte order: %s\n", pCksum->bSwap ? "swapped" : "native");
+  }
+  printf("WAL Header:\n");
+  print_decode_line(aData, 0, 4,1,"Magic.  0x377f0682 (le) or 0x377f0683 (be)");
+  print_decode_line(aData, 4, 4, 0, "File format");
+  print_decode_line(aData, 8, 4, 0, "Database page size");
+  print_decode_line(aData, 12,4, 0, "Checkpoint sequence number");
+  print_decode_line(aData, 16,4, 1, "Salt-1");
+  print_decode_line(aData, 20,4, 1, "Salt-2");
+  print_decode_line(aData, 24,4, 1, "Checksum-1");
+  print_decode_line(aData, 28,4, 1, "Checksum-2");
+  if( pCksum ){
+    if( pCksum->s0!=getInt32(aData+24) ){
+      printf("**** cksum-1 mismatch: 0x%08x\n", pCksum->s0);
+    }
+    if( pCksum->s1!=getInt32(aData+28) ){
+      printf("**** cksum-2 mismatch: 0x%08x\n", pCksum->s1);
+    }
+  }
+  free(aData);
+}
+/*
+** Describe cell content.
+*/
+static i64 describeContent(
+  unsigned char *a,       /* Cell content */
+  i64 nLocal,             /* Bytes in a[] */
+  char *zDesc             /* Write description here */
+){
+  int 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 = pagesize-35;
+    minLocal = (pagesize-12)*32/255-23;
+  }else{
+    maxLocal = (pagesize-12)*64/255-23;
+    minLocal = (pagesize-12)*32/255-23;
+  }
+  if( nPayload>maxLocal ){
+    surplus = minLocal + (nPayload-minLocal)%(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;
+}
+
+/*
+** Decode a btree page
+*/
+static void decode_btree_page(
+  unsigned char *a,   /* Content of the btree page to be decoded */
+  int pgno,           /* Page number */
+  int hdrSize,        /* Size of the page1-header in bytes */
+  const char *zArgs   /* Flags to control formatting */
+){
+  const char *zType = "unknown";
+  int nCell;
+  int i, j;
+  int iCellPtr;
+  int showCellContent = 0;
+  int showMap = 0;
+  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;
+    }
+    zArgs++;
+  }
+  printf("Decode of btree page %d:\n", pgno);
+  print_decode_line(a, 0, 1, 0, zType);
+  print_decode_line(a, 1, 2, 0, "Offset to first freeblock");
+  print_decode_line(a, 3, 2, 0, "Number of cells on this page");
+  nCell = a[3]*256 + a[4];
+  print_decode_line(a, 5, 2, 0, "Offset to cell content area");
+  print_decode_line(a, 7, 1, 0, "Fragmented byte count");
+  if( a[0]==2 || a[0]==5 ){
+    print_decode_line(a, 8, 4, 0, "Right child");
+    iCellPtr = 12;
+  }else{
+    iCellPtr = 8;
+  }
+  if( nCell>0 ){
+    printf(" key: lx=left-child n=payload-size r=rowid\n");
+  }
+  if( showMap ){
+    zMap = malloc(pagesize);
+    memset(zMap, '.', 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);
+    }
+    printf(" %03x: cell[%d] %s\n", cofst, i, zDesc);
+  }
+  if( showMap ){
+    for(i=0; i<pagesize; i+=64){
+      printf(" %03x: %.64s\n", i, &zMap[i]);
+    }
+    free(zMap);
+  }  
+}
+
+int main(int argc, char **argv){
+  struct stat sbuf;
+  unsigned char zPgSz[4];
+  if( argc<2 ){
+    fprintf(stderr,"Usage: %s FILENAME ?PAGE? ...\n", argv[0]);
+    exit(1);
+  }
+  fd = open(argv[1], O_RDONLY);
+  if( fd<0 ){
+    fprintf(stderr,"%s: can't open %s\n", argv[0], argv[1]);
+    exit(1);
+  }
+  zPgSz[0] = 0;
+  zPgSz[1] = 0;
+  lseek(fd, 8, SEEK_SET);
+  read(fd, zPgSz, 4);
+  pagesize = zPgSz[1]*65536 + zPgSz[2]*256 + zPgSz[3];
+  if( pagesize==0 ) pagesize = 1024;
+  printf("Pagesize: %d\n", pagesize);
+  fstat(fd, &sbuf);
+  if( sbuf.st_size<32 ){
+    printf("file too small to be a WAL\n");
+    return 0;
+  }
+  mxFrame = (sbuf.st_size - 32)/(pagesize + 24);
+  printf("Available pages: 1..%d\n", mxFrame);
+  if( argc==2 ){
+    int i;
+    Cksum x;
+    print_wal_header(&x);
+    for(i=1; i<=mxFrame; i++){
+      print_oneline_frame(i, &x);
+    }
+  }else{
+    int i;
+    for(i=2; i<argc; i++){
+      int iStart, iEnd;
+      char *zLeft;
+      if( strcmp(argv[i], "header")==0 ){
+        print_wal_header(0);
+        continue;
+      }
+      if( !ISDIGIT(argv[i][0]) ){
+        fprintf(stderr, "%s: unknown option: [%s]\n", argv[0], argv[i]);
+        continue;
+      }
+      iStart = strtol(argv[i], &zLeft, 0);
+      if( zLeft && strcmp(zLeft,"..end")==0 ){
+        iEnd = mxFrame;
+      }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 ){
+          hdrSize = 100;
+          ofst = hdrSize = 100;
+          nByte = pagesize-100;
+        }else{
+          hdrSize = 0;
+          ofst = (iStart-1)*pagesize;
+          nByte = pagesize;
+        }
+        ofst = 32 + hdrSize + (iStart-1)*(pagesize+24) + 24;
+        a = getContent(ofst, nByte);
+        decode_btree_page(a, iStart, hdrSize, zLeft+1);
+        free(a);
+        continue;
+      }else{
+        iEnd = iStart;
+      }
+      if( iStart<1 || iEnd<iStart || iEnd>mxFrame ){
+        fprintf(stderr,
+          "Page argument should be LOWER?..UPPER?.  Range 1 to %d\n",
+          mxFrame);
+        exit(1);
+      }
+      while( iStart<=iEnd ){
+        print_frame(iStart);
+        iStart++;
+      }
+    }
+  }
+  close(fd);
+  return 0;
+}