third_party/sqlite/src/tool/showstat4.c

   1 /*
   2 ** This utility program decodes and displays the content of the
   3 ** sqlite_stat4 table in the database file named on the command
   4 ** line.
   5 */
   6 #include <stdio.h>
   7 #include <string.h>
   8 #include <stdlib.h>
   9 #include <ctype.h>
  10 #include "sqlite3.h"
  11
  12 typedef sqlite3_int64 i64;   /* 64-bit signed integer type */
  13
  14
  15 /*
  16 ** Convert the var-int format into i64.  Return the number of bytes
  17 ** in the var-int.  Write the var-int value into *pVal.
  18 */
  19 static int decodeVarint(const unsigned char *z, i64 *pVal){
  20   i64 v = 0;
  21   int i;
  22   for(i=0; i<8; i++){
  23     v = (v<<7) + (z[i]&0x7f);
  24     if( (z[i]&0x80)==0 ){ *pVal = v; return i+1; }
  25   }
  26   v = (v<<8) + (z[i]&0xff);
  27   *pVal = v;
  28   return 9;
  29 }
  30
  31
  32
  33 int main(int argc, char **argv){
  34   sqlite3 *db;
  35   sqlite3_stmt *pStmt;
  36   char *zIdx = 0;
  37   int rc, j, x, y, mxHdr;
  38   const unsigned char *aSample;
  39   int nSample;
  40   i64 iVal;
  41   const char *zSep;
  42
  43   if( argc!=2 ){
  44     fprintf(stderr, "Usage: %s DATABASE-FILE\n", argv[0]);
  45     exit(1);
  46   }
  47   rc = sqlite3_open(argv[1], &db);
  48   if( rc!=SQLITE_OK || db==0 ){
  49     fprintf(stderr, "Cannot open database file [%s]\n", argv[1]);
  50     exit(1);
  51   }
  52   rc = sqlite3_prepare_v2(db,
  53         "SELECT tbl||'.'||idx, nEq, nLT, nDLt, sample "
  54         "FROM sqlite_stat4 ORDER BY 1", -1,
  55         &pStmt, 0);
  56   if( rc!=SQLITE_OK || pStmt==0 ){
  57     fprintf(stderr, "%s\n", sqlite3_errmsg(db));
  58     sqlite3_close(db);
  59     exit(1);
  60   }
  61   while( SQLITE_ROW==sqlite3_step(pStmt) ){
  62     if( zIdx==0 || strcmp(zIdx, (const char*)sqlite3_column_text(pStmt,0))!=0 ){
  63       if( zIdx ) printf("\n");
  64       sqlite3_free(zIdx);
  65       zIdx = sqlite3_mprintf("%s", sqlite3_column_text(pStmt,0));
  66       printf("%s:\n", zIdx);
  67     }else{
  68       printf("  -----------------------------------------------------------\n");
  69     }
  70     printf("  nEq    = %s\n", sqlite3_column_text(pStmt,1));
  71     printf("  nLt    = %s\n", sqlite3_column_text(pStmt,2));
  72     printf("  nDLt   = %s\n", sqlite3_column_text(pStmt,3));
  73     printf("  sample = x'");
  74     aSample = sqlite3_column_blob(pStmt,4);
  75     nSample = sqlite3_column_bytes(pStmt,4);
  76     for(j=0; j<nSample; j++) printf("%02x", aSample[j]);
  77     printf("'\n          ");
  78     zSep = " ";
  79     x = decodeVarint(aSample, &iVal);
  80     if( iVal<x || iVal>nSample ){
  81       printf(" <error>\n");
  82       continue;
  83     }
  84     y = mxHdr = (int)iVal;
  85     while( x<mxHdr ){
  86       int sz;
  87       i64 v;
  88       x += decodeVarint(aSample+x, &iVal);
  89       if( x>mxHdr ) break;
  90       if( iVal<0 ) break;
  91       switch( iVal ){
  92         case 0:  sz = 0;  break;
  93         case 1:  sz = 1;  break;
  94         case 2:  sz = 2;  break;
  95         case 3:  sz = 3;  break;
  96         case 4:  sz = 4;  break;
  97         case 5:  sz = 6;  break;
  98         case 6:  sz = 8;  break;
  99         case 7:  sz = 8;  break;
 100         case 8:  sz = 0;  break;
 101         case 9:  sz = 0;  break;
 102         case 10:
 103         case 11: sz = 0;  break;
 104         default: sz = (int)(iVal-12)/2;  break;
 105       }
 106       if( y+sz>nSample ) break;
 107       if( iVal==0 ){
 108         printf("%sNULL", zSep);
 109       }else if( iVal==8 || iVal==9 ){
 110         printf("%s%d", zSep, ((int)iVal)-8);
 111       }else if( iVal<=7 ){
 112         v = (signed char)aSample[y];
 113         for(j=1; j<sz; j++){
 114           v = (v<<8) + aSample[y+j];
 115         }
 116         if( iVal==7 ){
 117           double r;
 118           memcpy(&r, &v, sizeof(r));
 119           printf("%s%#g", zSep, r);
 120         }else{
 121           printf("%s%lld", zSep, v);
 122         }
 123       }else if( (iVal&1)==0 ){
 124         printf("%sx'", zSep);
 125         for(j=0; j<sz; j++){
 126           printf("%02x", aSample[y+j]);
 127         }
 128         printf("'");
 129       }else{
 130         printf("%s\"", zSep);
 131         for(j=0; j<sz; j++){
 132           char c = (char)aSample[y+j];
 133           if( isprint(c) ){
 134             if( c=='"' || c=='\\' ) putchar('\\');
 135             putchar(c);
 136           }else if( c=='\n' ){
 137             printf("\\n");
 138           }else if( c=='\t' ){
 139             printf("\\t");
 140           }else if( c=='\r' ){
 141             printf("\\r");
 142           }else{
 143             printf("\\%03o", c);
 144           }
 145         }
 146         printf("\"");
 147       }
 148       zSep = ",";
 149       y += sz;
 150     }
 151     printf("\n");
 152   }
 153   sqlite3_free(zIdx);
 154   sqlite3_finalize(pStmt);
 155   sqlite3_close(db);
 156   return 0;
 157 }