third_party/sqlite/src/src/test

/* [<][>][^][v][top][bottom][index][help] */
This source file includes following definitions.
fsDlSym
tmpClose
tmpRead
tmpWrite
tmpTruncate
tmpSync
tmpFileSize
tmpLock
tmpUnlock
tmpCheckReservedLock
tmpFileControl
tmpSectorSize
tmpDeviceCharacteristics
fsClose
fsRead
fsWrite
fsTruncate
fsSync
fsFileSize
fsLock
fsUnlock
fsCheckReservedLock
fsFileControl
fsSectorSize
fsDeviceCharacteristics
fsOpen
fsDelete
fsAccess
fsFullPathname
fsDlOpen
fsDlError
fsDlSym
fsDlClose
fsRandomness
fsSleep
fsCurrentTime
fs_register
SqlitetestOnefile_Init
/*
** 2007 September 14
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** OVERVIEW:
**
**   This file contains some example code demonstrating how the SQLite 
**   vfs feature can be used to have SQLite operate directly on an 
**   embedded media, without using an intermediate file system.
**
**   Because this is only a demo designed to run on a workstation, the
**   underlying media is simulated using a regular file-system file. The
**   size of the file is fixed when it is first created (default size 10 MB).
**   From SQLite's point of view, this space is used to store a single
**   database file and the journal file. 
**
**   Any statement journal created is stored in volatile memory obtained 
**   from sqlite3_malloc(). Any attempt to create a temporary database file 
**   will fail (SQLITE_IOERR). To prevent SQLite from attempting this,
**   it should be configured to store all temporary database files in 
**   main memory (see pragma "temp_store" or the SQLITE_TEMP_STORE compile 
**   time option).
**
** ASSUMPTIONS:
**
**   After it has been created, the blob file is accessed using the
**   following three functions only:
**
**       mediaRead();            - Read a 512 byte block from the file.
**       mediaWrite();           - Write a 512 byte block to the file.
**       mediaSync();            - Tell the media hardware to sync.
**
**   It is assumed that these can be easily implemented by any "real"
**   media vfs driver adapting this code.
**
** FILE FORMAT:
**
**   The basic principle is that the "database file" is stored at the
**   beginning of the 10 MB blob and grows in a forward direction. The 
**   "journal file" is stored at the end of the 10MB blob and grows
**   in the reverse direction. If, during a transaction, insufficient
**   space is available to expand either the journal or database file,
**   an SQLITE_FULL error is returned. The database file is never allowed
**   to consume more than 90% of the blob space. If SQLite tries to
**   create a file larger than this, SQLITE_FULL is returned.
**
**   No allowance is made for "wear-leveling", as is required by.
**   embedded devices in the absence of equivalent hardware features.
**
**   The first 512 block byte of the file is reserved for storing the
**   size of the "database file". It is updated as part of the sync()
**   operation. On startup, it can only be trusted if no journal file
**   exists. If a journal-file does exist, then it stores the real size
**   of the database region. The second and subsequent blocks store the 
**   actual database content.
**
**   The size of the "journal file" is not stored persistently in the 
**   file. When the system is running, the size of the journal file is
**   stored in volatile memory. When recovering from a crash, this vfs
**   reports a very large size for the journal file. The normal journal
**   header and checksum mechanisms serve to prevent SQLite from 
**   processing any data that lies past the logical end of the journal.
**
**   When SQLite calls OsDelete() to delete the journal file, the final
**   512 bytes of the blob (the area containing the first journal header)
**   are zeroed.
**
** LOCKING:
**
**   File locking is a no-op. Only one connection may be open at any one
**   time using this demo vfs.
*/

#include "sqlite3.h"
#include <assert.h>
#include <string.h>

/*
** Maximum pathname length supported by the fs backend.
*/
#define BLOCKSIZE 512
#define BLOBSIZE 10485760

/*
** Name used to identify this VFS.
*/
#define FS_VFS_NAME "fs"

typedef struct fs_real_file fs_real_file;
struct fs_real_file {
  sqlite3_file *pFile;
  const char *zName;
  int nDatabase;              /* Current size of database region */
  int nJournal;               /* Current size of journal region */
  int nBlob;                  /* Total size of allocated blob */
  int nRef;                   /* Number of pointers to this structure */
  fs_real_file *pNext;
  fs_real_file **ppThis;
};

typedef struct fs_file fs_file;
struct fs_file {
  sqlite3_file base;
  int eType;
  fs_real_file *pReal;
};

typedef struct tmp_file tmp_file;
struct tmp_file {
  sqlite3_file base;
  int nSize;
  int nAlloc;
  char *zAlloc;
};

/* Values for fs_file.eType. */
#define DATABASE_FILE   1
#define JOURNAL_FILE    2

/*
** Method declarations for fs_file.
*/
static int fsClose(sqlite3_file*);
static int fsRead(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
static int fsWrite(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
static int fsTruncate(sqlite3_file*, sqlite3_int64 size);
static int fsSync(sqlite3_file*, int flags);
static int fsFileSize(sqlite3_file*, sqlite3_int64 *pSize);
static int fsLock(sqlite3_file*, int);
static int fsUnlock(sqlite3_file*, int);
static int fsCheckReservedLock(sqlite3_file*, int *pResOut);
static int fsFileControl(sqlite3_file*, int op, void *pArg);
static int fsSectorSize(sqlite3_file*);
static int fsDeviceCharacteristics(sqlite3_file*);

/*
** Method declarations for tmp_file.
*/
static int tmpClose(sqlite3_file*);
static int tmpRead(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
static int tmpWrite(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
static int tmpTruncate(sqlite3_file*, sqlite3_int64 size);
static int tmpSync(sqlite3_file*, int flags);
static int tmpFileSize(sqlite3_file*, sqlite3_int64 *pSize);
static int tmpLock(sqlite3_file*, int);
static int tmpUnlock(sqlite3_file*, int);
static int tmpCheckReservedLock(sqlite3_file*, int *pResOut);
static int tmpFileControl(sqlite3_file*, int op, void *pArg);
static int tmpSectorSize(sqlite3_file*);
static int tmpDeviceCharacteristics(sqlite3_file*);

/*
** Method declarations for fs_vfs.
*/
static int fsOpen(sqlite3_vfs*, const char *, sqlite3_file*, int , int *);
static int fsDelete(sqlite3_vfs*, const char *zName, int syncDir);
static int fsAccess(sqlite3_vfs*, const char *zName, int flags, int *);
static int fsFullPathname(sqlite3_vfs*, const char *zName, int nOut,char *zOut);
static void *fsDlOpen(sqlite3_vfs*, const char *zFilename);
static void fsDlError(sqlite3_vfs*, int nByte, char *zErrMsg);
static void (*fsDlSym(sqlite3_vfs*,void*, const char *zSymbol))(void);
static void fsDlClose(sqlite3_vfs*, void*);
static int fsRandomness(sqlite3_vfs*, int nByte, char *zOut);
static int fsSleep(sqlite3_vfs*, int microseconds);
static int fsCurrentTime(sqlite3_vfs*, double*);


typedef struct fs_vfs_t fs_vfs_t;
struct fs_vfs_t {
  sqlite3_vfs base;
  fs_real_file *pFileList;
  sqlite3_vfs *pParent;
};

static fs_vfs_t fs_vfs = {
  {
    1,                                          /* iVersion */
    0,                                          /* szOsFile */
    0,                                          /* mxPathname */
    0,                                          /* pNext */
    FS_VFS_NAME,                                /* zName */
    0,                                          /* pAppData */
    fsOpen,                                     /* xOpen */
    fsDelete,                                   /* xDelete */
    fsAccess,                                   /* xAccess */
    fsFullPathname,                             /* xFullPathname */
    fsDlOpen,                                   /* xDlOpen */
    fsDlError,                                  /* xDlError */
    fsDlSym,                                    /* xDlSym */
    fsDlClose,                                  /* xDlClose */
    fsRandomness,                               /* xRandomness */
    fsSleep,                                    /* xSleep */
    fsCurrentTime,                              /* xCurrentTime */
    0                                           /* xCurrentTimeInt64 */
  }, 
  0,                                            /* pFileList */
  0                                             /* pParent */
};

static sqlite3_io_methods fs_io_methods = {
  1,                            /* iVersion */
  fsClose,                      /* xClose */
  fsRead,                       /* xRead */
  fsWrite,                      /* xWrite */
  fsTruncate,                   /* xTruncate */
  fsSync,                       /* xSync */
  fsFileSize,                   /* xFileSize */
  fsLock,                       /* xLock */
  fsUnlock,                     /* xUnlock */
  fsCheckReservedLock,          /* xCheckReservedLock */
  fsFileControl,                /* xFileControl */
  fsSectorSize,                 /* xSectorSize */
  fsDeviceCharacteristics,      /* xDeviceCharacteristics */
  0,                            /* xShmMap */
  0,                            /* xShmLock */
  0,                            /* xShmBarrier */
  0                             /* xShmUnmap */
};


static sqlite3_io_methods tmp_io_methods = {
  1,                            /* iVersion */
  tmpClose,                     /* xClose */
  tmpRead,                      /* xRead */
  tmpWrite,                     /* xWrite */
  tmpTruncate,                  /* xTruncate */
  tmpSync,                      /* xSync */
  tmpFileSize,                  /* xFileSize */
  tmpLock,                      /* xLock */
  tmpUnlock,                    /* xUnlock */
  tmpCheckReservedLock,         /* xCheckReservedLock */
  tmpFileControl,               /* xFileControl */
  tmpSectorSize,                /* xSectorSize */
  tmpDeviceCharacteristics,     /* xDeviceCharacteristics */
  0,                            /* xShmMap */
  0,                            /* xShmLock */
  0,                            /* xShmBarrier */
  0                             /* xShmUnmap */
};

/* Useful macros used in several places */
#define MIN(x,y) ((x)<(y)?(x):(y))
#define MAX(x,y) ((x)>(y)?(x):(y))


/*
** Close a tmp-file.
*/
static int tmpClose(sqlite3_file *pFile){
  tmp_file *pTmp = (tmp_file *)pFile;
  sqlite3_free(pTmp->zAlloc);
  return SQLITE_OK;
}

/*
** Read data from a tmp-file.
*/
static int tmpRead(
  sqlite3_file *pFile, 
  void *zBuf, 
  int iAmt, 
  sqlite_int64 iOfst
){
  tmp_file *pTmp = (tmp_file *)pFile;
  if( (iAmt+iOfst)>pTmp->nSize ){
    return SQLITE_IOERR_SHORT_READ;
  }
  memcpy(zBuf, &pTmp->zAlloc[iOfst], iAmt);
  return SQLITE_OK;
}

/*
** Write data to a tmp-file.
*/
static int tmpWrite(
  sqlite3_file *pFile, 
  const void *zBuf, 
  int iAmt, 
  sqlite_int64 iOfst
){
  tmp_file *pTmp = (tmp_file *)pFile;
  if( (iAmt+iOfst)>pTmp->nAlloc ){
    int nNew = 2*(iAmt+iOfst+pTmp->nAlloc);
    char *zNew = sqlite3_realloc(pTmp->zAlloc, nNew);
    if( !zNew ){
      return SQLITE_NOMEM;
    }
    pTmp->zAlloc = zNew;
    pTmp->nAlloc = nNew;
  }
  memcpy(&pTmp->zAlloc[iOfst], zBuf, iAmt);
  pTmp->nSize = MAX(pTmp->nSize, iOfst+iAmt);
  return SQLITE_OK;
}

/*
** Truncate a tmp-file.
*/
static int tmpTruncate(sqlite3_file *pFile, sqlite_int64 size){
  tmp_file *pTmp = (tmp_file *)pFile;
  pTmp->nSize = MIN(pTmp->nSize, size);
  return SQLITE_OK;
}

/*
** Sync a tmp-file.
*/
static int tmpSync(sqlite3_file *pFile, int flags){
  return SQLITE_OK;
}

/*
** Return the current file-size of a tmp-file.
*/
static int tmpFileSize(sqlite3_file *pFile, sqlite_int64 *pSize){
  tmp_file *pTmp = (tmp_file *)pFile;
  *pSize = pTmp->nSize;
  return SQLITE_OK;
}

/*
** Lock a tmp-file.
*/
static int tmpLock(sqlite3_file *pFile, int eLock){
  return SQLITE_OK;
}

/*
** Unlock a tmp-file.
*/
static int tmpUnlock(sqlite3_file *pFile, int eLock){
  return SQLITE_OK;
}

/*
** Check if another file-handle holds a RESERVED lock on a tmp-file.
*/
static int tmpCheckReservedLock(sqlite3_file *pFile, int *pResOut){
  *pResOut = 0;
  return SQLITE_OK;
}

/*
** File control method. For custom operations on a tmp-file.
*/
static int tmpFileControl(sqlite3_file *pFile, int op, void *pArg){
  return SQLITE_OK;
}

/*
** Return the sector-size in bytes for a tmp-file.
*/
static int tmpSectorSize(sqlite3_file *pFile){
  return 0;
}

/*
** Return the device characteristic flags supported by a tmp-file.
*/
static int tmpDeviceCharacteristics(sqlite3_file *pFile){
  return 0;
}

/*
** Close an fs-file.
*/
static int fsClose(sqlite3_file *pFile){
  int rc = SQLITE_OK;
  fs_file *p = (fs_file *)pFile;
  fs_real_file *pReal = p->pReal;

  /* Decrement the real_file ref-count. */
  pReal->nRef--;
  assert(pReal->nRef>=0);

  /* When the ref-count reaches 0, destroy the structure */
  if( pReal->nRef==0 ){
    *pReal->ppThis = pReal->pNext;
    if( pReal->pNext ){
      pReal->pNext->ppThis = pReal->ppThis;
    }
    rc = pReal->pFile->pMethods->xClose(pReal->pFile);
    sqlite3_free(pReal);
  }

  return rc;
}

/*
** Read data from an fs-file.
*/
static int fsRead(
  sqlite3_file *pFile, 
  void *zBuf, 
  int iAmt, 
  sqlite_int64 iOfst
){
  int rc = SQLITE_OK;
  fs_file *p = (fs_file *)pFile;
  fs_real_file *pReal = p->pReal;
  sqlite3_file *pF = pReal->pFile;

  if( (p->eType==DATABASE_FILE && (iAmt+iOfst)>pReal->nDatabase)
   || (p->eType==JOURNAL_FILE && (iAmt+iOfst)>pReal->nJournal)
  ){
    rc = SQLITE_IOERR_SHORT_READ;
  }else if( p->eType==DATABASE_FILE ){
    rc = pF->pMethods->xRead(pF, zBuf, iAmt, iOfst+BLOCKSIZE);
  }else{
    /* Journal file. */
    int iRem = iAmt;
    int iBuf = 0;
    int ii = iOfst;
    while( iRem>0 && rc==SQLITE_OK ){
      int iRealOff = pReal->nBlob - BLOCKSIZE*((ii/BLOCKSIZE)+1) + ii%BLOCKSIZE;
      int iRealAmt = MIN(iRem, BLOCKSIZE - (iRealOff%BLOCKSIZE));

      rc = pF->pMethods->xRead(pF, &((char *)zBuf)[iBuf], iRealAmt, iRealOff);
      ii += iRealAmt;
      iBuf += iRealAmt;
      iRem -= iRealAmt;
    }
  }

  return rc;
}

/*
** Write data to an fs-file.
*/
static int fsWrite(
  sqlite3_file *pFile, 
  const void *zBuf, 
  int iAmt, 
  sqlite_int64 iOfst
){
  int rc = SQLITE_OK;
  fs_file *p = (fs_file *)pFile;
  fs_real_file *pReal = p->pReal;
  sqlite3_file *pF = pReal->pFile;

  if( p->eType==DATABASE_FILE ){
    if( (iAmt+iOfst+BLOCKSIZE)>(pReal->nBlob-pReal->nJournal) ){
      rc = SQLITE_FULL;
    }else{
      rc = pF->pMethods->xWrite(pF, zBuf, iAmt, iOfst+BLOCKSIZE);
      if( rc==SQLITE_OK ){
        pReal->nDatabase = MAX(pReal->nDatabase, iAmt+iOfst);
      }
    }
  }else{
    /* Journal file. */
    int iRem = iAmt;
    int iBuf = 0;
    int ii = iOfst;
    while( iRem>0 && rc==SQLITE_OK ){
      int iRealOff = pReal->nBlob - BLOCKSIZE*((ii/BLOCKSIZE)+1) + ii%BLOCKSIZE;
      int iRealAmt = MIN(iRem, BLOCKSIZE - (iRealOff%BLOCKSIZE));

      if( iRealOff<(pReal->nDatabase+BLOCKSIZE) ){
        rc = SQLITE_FULL;
      }else{
        rc = pF->pMethods->xWrite(pF, &((char *)zBuf)[iBuf], iRealAmt,iRealOff);
        ii += iRealAmt;
        iBuf += iRealAmt;
        iRem -= iRealAmt;
      }
    }
    if( rc==SQLITE_OK ){
      pReal->nJournal = MAX(pReal->nJournal, iAmt+iOfst);
    }
  }

  return rc;
}

/*
** Truncate an fs-file.
*/
static int fsTruncate(sqlite3_file *pFile, sqlite_int64 size){
  fs_file *p = (fs_file *)pFile;
  fs_real_file *pReal = p->pReal;
  if( p->eType==DATABASE_FILE ){
    pReal->nDatabase = MIN(pReal->nDatabase, size);
  }else{
    pReal->nJournal = MIN(pReal->nJournal, size);
  }
  return SQLITE_OK;
}

/*
** Sync an fs-file.
*/
static int fsSync(sqlite3_file *pFile, int flags){
  fs_file *p = (fs_file *)pFile;
  fs_real_file *pReal = p->pReal;
  sqlite3_file *pRealFile = pReal->pFile;
  int rc = SQLITE_OK;

  if( p->eType==DATABASE_FILE ){
    unsigned char zSize[4];
    zSize[0] = (pReal->nDatabase&0xFF000000)>>24;
    zSize[1] = (pReal->nDatabase&0x00FF0000)>>16;
    zSize[2] = (pReal->nDatabase&0x0000FF00)>>8;
    zSize[3] = (pReal->nDatabase&0x000000FF);
    rc = pRealFile->pMethods->xWrite(pRealFile, zSize, 4, 0);
  }
  if( rc==SQLITE_OK ){
    rc = pRealFile->pMethods->xSync(pRealFile, flags&(~SQLITE_SYNC_DATAONLY));
  }

  return rc;
}

/*
** Return the current file-size of an fs-file.
*/
static int fsFileSize(sqlite3_file *pFile, sqlite_int64 *pSize){
  fs_file *p = (fs_file *)pFile;
  fs_real_file *pReal = p->pReal;
  if( p->eType==DATABASE_FILE ){
    *pSize = pReal->nDatabase;
  }else{
    *pSize = pReal->nJournal;
  }
  return SQLITE_OK;
}

/*
** Lock an fs-file.
*/
static int fsLock(sqlite3_file *pFile, int eLock){
  return SQLITE_OK;
}

/*
** Unlock an fs-file.
*/
static int fsUnlock(sqlite3_file *pFile, int eLock){
  return SQLITE_OK;
}

/*
** Check if another file-handle holds a RESERVED lock on an fs-file.
*/
static int fsCheckReservedLock(sqlite3_file *pFile, int *pResOut){
  *pResOut = 0;
  return SQLITE_OK;
}

/*
** File control method. For custom operations on an fs-file.
*/
static int fsFileControl(sqlite3_file *pFile, int op, void *pArg){
  return SQLITE_OK;
}

/*
** Return the sector-size in bytes for an fs-file.
*/
static int fsSectorSize(sqlite3_file *pFile){
  return BLOCKSIZE;
}

/*
** Return the device characteristic flags supported by an fs-file.
*/
static int fsDeviceCharacteristics(sqlite3_file *pFile){
  return 0;
}

/*
** Open an fs file handle.
*/
static int fsOpen(
  sqlite3_vfs *pVfs,
  const char *zName,
  sqlite3_file *pFile,
  int flags,
  int *pOutFlags
){
  fs_vfs_t *pFsVfs = (fs_vfs_t *)pVfs;
  fs_file *p = (fs_file *)pFile;
  fs_real_file *pReal = 0;
  int eType;
  int nName;
  int rc = SQLITE_OK;

  if( 0==(flags&(SQLITE_OPEN_MAIN_DB|SQLITE_OPEN_MAIN_JOURNAL)) ){
    tmp_file *p = (tmp_file *)pFile;
    memset(p, 0, sizeof(*p));
    p->base.pMethods = &tmp_io_methods;
    return SQLITE_OK;
  }

  eType = ((flags&(SQLITE_OPEN_MAIN_DB))?DATABASE_FILE:JOURNAL_FILE);
  p->base.pMethods = &fs_io_methods;
  p->eType = eType;

  assert(strlen("-journal")==8);
  nName = strlen(zName)-((eType==JOURNAL_FILE)?8:0);
  pReal=pFsVfs->pFileList; 
  for(; pReal && strncmp(pReal->zName, zName, nName); pReal=pReal->pNext);

  if( !pReal ){
    int real_flags = (flags&~(SQLITE_OPEN_MAIN_DB))|SQLITE_OPEN_TEMP_DB;
    sqlite3_int64 size;
    sqlite3_file *pRealFile;
    sqlite3_vfs *pParent = pFsVfs->pParent;
    assert(eType==DATABASE_FILE);

    pReal = (fs_real_file *)sqlite3_malloc(sizeof(*pReal)+pParent->szOsFile);
    if( !pReal ){
      rc = SQLITE_NOMEM;
      goto open_out;
    }
    memset(pReal, 0, sizeof(*pReal)+pParent->szOsFile);
    pReal->zName = zName;
    pReal->pFile = (sqlite3_file *)(&pReal[1]);

    rc = pParent->xOpen(pParent, zName, pReal->pFile, real_flags, pOutFlags);
    if( rc!=SQLITE_OK ){
      goto open_out;
    }
    pRealFile = pReal->pFile;

    rc = pRealFile->pMethods->xFileSize(pRealFile, &size);
    if( rc!=SQLITE_OK ){
      goto open_out;
    }
    if( size==0 ){
      rc = pRealFile->pMethods->xWrite(pRealFile, "\0", 1, BLOBSIZE-1);
      pReal->nBlob = BLOBSIZE;
    }else{
      unsigned char zS[4];
      pReal->nBlob = size;
      rc = pRealFile->pMethods->xRead(pRealFile, zS, 4, 0);
      pReal->nDatabase = (zS[0]<<24)+(zS[1]<<16)+(zS[2]<<8)+zS[3];
      if( rc==SQLITE_OK ){
        rc = pRealFile->pMethods->xRead(pRealFile, zS, 4, pReal->nBlob-4);
        if( zS[0] || zS[1] || zS[2] || zS[3] ){
          pReal->nJournal = pReal->nBlob;
        }
      }
    }

    if( rc==SQLITE_OK ){
      pReal->pNext = pFsVfs->pFileList;
      if( pReal->pNext ){
        pReal->pNext->ppThis = &pReal->pNext;
      }
      pReal->ppThis = &pFsVfs->pFileList;
      pFsVfs->pFileList = pReal;
    }
  }

open_out:
  if( pReal ){
    if( rc==SQLITE_OK ){
      p->pReal = pReal;
      pReal->nRef++;
    }else{
      if( pReal->pFile->pMethods ){
        pReal->pFile->pMethods->xClose(pReal->pFile);
      }
      sqlite3_free(pReal);
    }
  }
  return rc;
}

/*
** Delete the file located at zPath. If the dirSync argument is true,
** ensure the file-system modifications are synced to disk before
** returning.
*/
static int fsDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){
  int rc = SQLITE_OK;
  fs_vfs_t *pFsVfs = (fs_vfs_t *)pVfs;
  fs_real_file *pReal;
  sqlite3_file *pF;
  int nName = strlen(zPath) - 8;

  assert(strlen("-journal")==8);
  assert(strcmp("-journal", &zPath[nName])==0);

  pReal = pFsVfs->pFileList; 
  for(; pReal && strncmp(pReal->zName, zPath, nName); pReal=pReal->pNext);
  if( pReal ){
    pF = pReal->pFile;
    rc = pF->pMethods->xWrite(pF, "\0\0\0\0", 4, pReal->nBlob-BLOCKSIZE);
    if( rc==SQLITE_OK ){
      pReal->nJournal = 0;
    }
  }
  return rc;
}

/*
** Test for access permissions. Return true if the requested permission
** is available, or false otherwise.
*/
static int fsAccess(
  sqlite3_vfs *pVfs, 
  const char *zPath, 
  int flags, 
  int *pResOut
){
  fs_vfs_t *pFsVfs = (fs_vfs_t *)pVfs;
  fs_real_file *pReal;
  int isJournal = 0;
  int nName = strlen(zPath);

  if( flags!=SQLITE_ACCESS_EXISTS ){
    sqlite3_vfs *pParent = ((fs_vfs_t *)pVfs)->pParent;
    return pParent->xAccess(pParent, zPath, flags, pResOut);
  }

  assert(strlen("-journal")==8);
  if( nName>8 && strcmp("-journal", &zPath[nName-8])==0 ){
    nName -= 8;
    isJournal = 1;
  }

  pReal = pFsVfs->pFileList; 
  for(; pReal && strncmp(pReal->zName, zPath, nName); pReal=pReal->pNext);

  *pResOut = (pReal && (!isJournal || pReal->nJournal>0));
  return SQLITE_OK;
}

/*
** Populate buffer zOut with the full canonical pathname corresponding
** to the pathname in zPath. zOut is guaranteed to point to a buffer
** of at least (FS_MAX_PATHNAME+1) bytes.
*/
static int fsFullPathname(
  sqlite3_vfs *pVfs,            /* Pointer to vfs object */
  const char *zPath,            /* Possibly relative input path */
  int nOut,                     /* Size of output buffer in bytes */
  char *zOut                    /* Output buffer */
){
  sqlite3_vfs *pParent = ((fs_vfs_t *)pVfs)->pParent;
  return pParent->xFullPathname(pParent, zPath, nOut, zOut);
}

/*
** Open the dynamic library located at zPath and return a handle.
*/
static void *fsDlOpen(sqlite3_vfs *pVfs, const char *zPath){
  sqlite3_vfs *pParent = ((fs_vfs_t *)pVfs)->pParent;
  return pParent->xDlOpen(pParent, zPath);
}

/*
** Populate the buffer zErrMsg (size nByte bytes) with a human readable
** utf-8 string describing the most recent error encountered associated 
** with dynamic libraries.
*/
static void fsDlError(sqlite3_vfs *pVfs, int nByte, char *zErrMsg){
  sqlite3_vfs *pParent = ((fs_vfs_t *)pVfs)->pParent;
  pParent->xDlError(pParent, nByte, zErrMsg);
}

/*
** Return a pointer to the symbol zSymbol in the dynamic library pHandle.
*/
static void (*fsDlSym(sqlite3_vfs *pVfs, void *pH, const char *zSym))(void){
  sqlite3_vfs *pParent = ((fs_vfs_t *)pVfs)->pParent;
  return pParent->xDlSym(pParent, pH, zSym);
}

/*
** Close the dynamic library handle pHandle.
*/
static void fsDlClose(sqlite3_vfs *pVfs, void *pHandle){
  sqlite3_vfs *pParent = ((fs_vfs_t *)pVfs)->pParent;
  pParent->xDlClose(pParent, pHandle);
}

/*
** Populate the buffer pointed to by zBufOut with nByte bytes of 
** random data.
*/
static int fsRandomness(sqlite3_vfs *pVfs, int nByte, char *zBufOut){
  sqlite3_vfs *pParent = ((fs_vfs_t *)pVfs)->pParent;
  return pParent->xRandomness(pParent, nByte, zBufOut);
}

/*
** Sleep for nMicro microseconds. Return the number of microseconds 
** actually slept.
*/
static int fsSleep(sqlite3_vfs *pVfs, int nMicro){
  sqlite3_vfs *pParent = ((fs_vfs_t *)pVfs)->pParent;
  return pParent->xSleep(pParent, nMicro);
}

/*
** Return the current time as a Julian Day number in *pTimeOut.
*/
static int fsCurrentTime(sqlite3_vfs *pVfs, double *pTimeOut){
  sqlite3_vfs *pParent = ((fs_vfs_t *)pVfs)->pParent;
  return pParent->xCurrentTime(pParent, pTimeOut);
}

/*
** This procedure registers the fs vfs with SQLite. If the argument is
** true, the fs vfs becomes the new default vfs. It is the only publicly
** available function in this file.
*/
int fs_register(void){
  if( fs_vfs.pParent ) return SQLITE_OK;
  fs_vfs.pParent = sqlite3_vfs_find(0);
  fs_vfs.base.mxPathname = fs_vfs.pParent->mxPathname;
  fs_vfs.base.szOsFile = MAX(sizeof(tmp_file), sizeof(fs_file));
  return sqlite3_vfs_register(&fs_vfs.base, 0);
}

#ifdef SQLITE_TEST
  int SqlitetestOnefile_Init() {return fs_register();}
#endif
/* [<][>][^][v][top][bottom][index][help] */
root/third_party/sqlite/src/src/test_onefile.c

DEFINITIONS
