SQLite

int sqlite3Fts5IndexReinit(Fts5Index *p);
int sqlite3Fts5IndexOptimize(Fts5Index *p);

int sqlite3Fts5IndexLoadConfig(Fts5Index *p);

int sqlite3Fts5GetVarint32(const unsigned char *p, u32 *v);
#define fts5GetVarint32(a,b) sqlite3Fts5GetVarint32(a,(u32*)&b)

int sqlite3Fts5GetVarintLen(u32 iVal);

/*
** End of interface to code in fts5_index.c.
**************************************************************************/

/**************************************************************************
** Interface to code in fts5_hash.c. 

  }

  sqlite3_free(apOld);
  pHash->nSlot = nNew;
  pHash->aSlot = apNew;
  return SQLITE_OK;
}

static void fts5HashAddPoslistSize(Fts5HashEntry *p){
  if( p->iSzPoslist ){
    u8 *pPtr = (u8*)p;
    int nSz = p->nData - p->iSzPoslist - 1;

    if( nSz<=127 ){
      pPtr[p->iSzPoslist] = nSz;
    }else{
      int nByte = sqlite3Fts5GetVarintLen((u32)nSz);
      memmove(&pPtr[p->iSzPoslist + nByte], &pPtr[p->iSzPoslist + 1], nSz);
      sqlite3PutVarint(&pPtr[p->iSzPoslist], nSz);
      p->nData += (nByte-1);
    }
    p->iSzPoslist = 0;
  }
}

int sqlite3Fts5HashWrite(
  Fts5Hash *pHash,
  i64 iRowid,                     /* Rowid for this entry */
  int iCol,                       /* Column token appears in (-ve -> delete) */
  int iPos,                       /* Position of token within column */
  const char *pToken, int nToken  /* Token to add or remove to or from index */

    memset(p, 0, sizeof(Fts5HashEntry));
    p->nAlloc = nByte;
    memcpy(p->zKey, pToken, nToken);
    p->zKey[nToken] = '\0';
    p->nData = nToken + 1 + sizeof(Fts5HashEntry);
    p->nData += sqlite3PutVarint(&((u8*)p)[p->nData], iRowid);
    p->iSzPoslist = p->nData;
    p->nData += 1;
    p->iRowid = iRowid;
    p->pHashNext = pHash->aSlot[iHash];
    pHash->aSlot[iHash] = p;
    pHash->nEntry++;
    nIncr += p->nData;
  }

  /* Check there is enough space to append a new entry. Worst case scenario
  ** is:
  **
  **     + 9 bytes for a new rowid,
  **     + 4 byte reserved for the "poslist size" varint.
  **     + 1 byte for a "new column" byte,
  **     + 3 bytes for a new column number (16-bit max) as a varint,
  **     + 5 bytes for the new position offset (32-bit max).
  */
  if( (p->nAlloc - p->nData) < (9 + 4 + 1 + 3 + 5) ){
    int nNew = p->nAlloc * 2;
    Fts5HashEntry *pNew;

  }
  pPtr = (u8*)p;
  nIncr -= p->nData;

  /* If this is a new rowid, append the 4-byte size field for the previous
  ** entry, and the new rowid for this entry.  */
  if( iRowid!=p->iRowid ){
    fts5HashAddPoslistSize(p);

    p->nData += sqlite3PutVarint(&pPtr[p->nData], iRowid - p->iRowid);
    p->iSzPoslist = p->nData;
    p->nData += 1;
    p->iCol = 0;
    p->iPos = 0;
    p->iRowid = iRowid;
  }

  if( iCol>=0 ){
    /* Append a new column value, if necessary */

  rc = fts5HashEntrySort(pHash, 0, 0, &pList);
  if( rc==SQLITE_OK ){
    memset(pHash->aSlot, 0, sizeof(Fts5HashEntry*) * pHash->nSlot);
    while( pList ){
      Fts5HashEntry *pNext = pList->pScanNext;
      if( rc==SQLITE_OK ){

        const int nKey = strlen(pList->zKey);
        i64 iRowid = 0;
        u8 *pPtr = (u8*)pList;
        int iOff = sizeof(Fts5HashEntry) + nKey + 1;

        /* Fill in the final poslist size field */
        fts5HashAddPoslistSize(pList);
        
        /* Issue the new-term callback */
        rc = xTerm(pCtx, pList->zKey, nKey);

        /* Issue the xEntry callbacks */
        while( rc==SQLITE_OK && iOff<pList->nData ){
          i64 iDelta;             /* Rowid delta value */
          int nPoslist;           /* Size of position list in bytes */
          int nVarint;
          iOff += getVarint(&pPtr[iOff], (u64*)&iDelta);
          iRowid += iDelta;
          nVarint = fts5GetVarint32(&pPtr[iOff], nPoslist);

          rc = xEntry(pCtx, iRowid, &pPtr[iOff], nPoslist+nVarint);
          iOff += nVarint+nPoslist;
        }

        /* Issue the term-done callback */
        if( rc==SQLITE_OK ) rc = xTermDone(pCtx);
      }
      sqlite3_free(pList);
      pList = pNext;

  Fts5HashEntry *p;

  for(p=pHash->aSlot[iHash]; p; p=p->pHashNext){
    if( memcmp(p->zKey, pTerm, nTerm)==0 && p->zKey[nTerm]==0 ) break;
  }

  if( p ){

    fts5HashAddPoslistSize(p);
    *ppDoclist = &p->zKey[nTerm+1];
    *pnDoclist = p->nData - (sizeof(*p) + nTerm + 1);
  }else{
    *ppDoclist = 0;
    *pnDoclist = 0;
  }

  Fts5Hash *pHash,
  const char **pzTerm,            /* OUT: term (nul-terminated) */
  const char **ppDoclist,         /* OUT: pointer to doclist */
  int *pnDoclist                  /* OUT: size of doclist in bytes */
){
  Fts5HashEntry *p;
  if( (p = pHash->pScan) ){

    int nTerm = strlen(p->zKey);
    fts5HashAddPoslistSize(p);
    *pzTerm = p->zKey;
    *ppDoclist = &p->zKey[nTerm+1];
    *pnDoclist = p->nData - (sizeof(*p) + nTerm + 1);
  }else{
    *pzTerm = 0;
    *ppDoclist = 0;
    *pnDoclist = 0;
  }
}

/*
** An object of type Fts5SegWriter is used to write to segments.
*/
struct Fts5PageWriter {
  int pgno;                       /* Page number for this page */
  Fts5Buffer buf;                 /* Buffer containing page data */
  Fts5Buffer term;                /* Buffer containing previous term on page */
};
struct Fts5SegWriter {
  int iIdx;                       /* Index to write to */
  int iSegid;                     /* Segid to write to */
  int nWriter;                    /* Number of entries in aWriter */
  Fts5PageWriter *aWriter;        /* Array of PageWriter objects */
  i64 iPrevRowid;                 /* Previous docid written to current leaf */

    p -= 2;
    n = sqlite3GetVarint(p, &v64);
    *v = (u32)v64;
    assert( n>3 && n<=9 );
    return n;
  }
}

int sqlite3Fts5GetVarintLen(u32 iVal){
  if( iVal<(1 << 7 ) ) return 1;
  if( iVal<(1 << 14) ) return 2;
  if( iVal<(1 << 21) ) return 3;
  if( iVal<(1 << 28) ) return 4;
  return 5;
}

/*
** Allocate and return a buffer at least nByte bytes in size.
**
** If an OOM error is encountered, return NULL and set the error code in
** the Fts5Index handle passed as the first argument.
*/

proc usage {} {
  puts stderr "Usage: $::argv0 ?SWITCHES? DATABASE PATH"
  puts stderr ""
  puts stderr "Switches are:"
  puts stderr "  -fts4        (use fts4 instead of fts5)"
  puts stderr "  -fts5        (use fts5)"
  puts stderr "  -porter      (use porter tokenizer)"
  puts stderr "  -delete      (delete the database file before starting)"
  puts stderr "  -limit N     (load no more than N documents)"
  puts stderr "  -automerge N (set the automerge parameter to N)"
  puts stderr "  -crisismerge N (set the crisismerge parameter to N)"
  exit 1
}

set O(vtab)       fts5
set O(tok)        ""
set O(limit)      0
set O(delete)     0
set O(automerge)  -1
set O(crisismerge)  -1

if {[llength $argv]<2} usage
set nOpt [expr {[llength $argv]-2}]
for {set i 0} {$i < $nOpt} {incr i} {
  set arg [lindex $argv $i]
  switch -- [lindex $argv $i] {
    -fts4 {
      set O(vtab) fts4
    }

    -fts5 {
      set O(vtab) fts5
    }

    -porter {
      set O(tok) ", tokenize=porter"
    }

    -delete {
      set O(delete) 1
    }

    -limit {
      if { [incr i]>=$nOpt } usage
      set O(limit) [lindex $argv $i]
    }
    
    -automerge {

    default {
      usage
    }
  }
}

set dbfile [lindex $argv end-1]
if {$O(delete)} { file delete -force $dbfile }
sqlite3 db $dbfile
db func loadfile loadfile

db transaction {
  catch {
    db eval "CREATE VIRTUAL TABLE t1 USING $O(vtab) (path, content$O(tok))"
  }
  if {$O(automerge)>=0} {