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Overview
Comment:Eliminate some of the "unused parameter" warnings in os_unix.c. (CVS 5923)
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1:2f5aaad90b7e3bbb31866c43db3e24a1be26f03b
User & Date: danielk1977 2008-11-19 11:35:40
Context
2008-11-19
12:43
Version number to 3.6.6. (CVS 5924) check-in: 8cc120fb user: drh tags: trunk
11:35
Eliminate some of the "unused parameter" warnings in os_unix.c. (CVS 5923) check-in: 2f5aaad9 user: danielk1977 tags: trunk
10:22
Simplify the way the pager layer invokes the busy-handler callback. (CVS 5922) check-in: 7bd1ac18 user: danielk1977 tags: trunk
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to src/os_unix.c.

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**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
******************************************************************************
**
** This file contains code that is specific to Unix systems.
**
** $Id: os_unix.c,v 1.212 2008/11/19 09:05:27 danielk1977 Exp $
*/
#include "sqliteInt.h"
#if SQLITE_OS_UNIX              /* This file is used on unix only */

/*
** If SQLITE_ENABLE_LOCKING_STYLE is defined and is non-zero, then several
** alternative locking implementations are provided:
................................................................................
#  if defined(__DARWIN__)
#    define SQLITE_ENABLE_LOCKING_STYLE 1
#  else
#    define SQLITE_ENABLE_LOCKING_STYLE 0
#  endif
#endif











/*
** These #defines should enable >2GB file support on Posix if the
** underlying operating system supports it.  If the OS lacks
** large file support, these should be no-ops.
**
** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
** on the compiler command line.  This is necessary if you are compiling
................................................................................
** for testing when we want to run through the test suite quickly.
** You are strongly advised *not* to deploy with SQLITE_NO_SYNC
** enabled, however, since with SQLITE_NO_SYNC enabled, an OS crash
** or power failure will likely corrupt the database file.
*/
static int full_fsync(int fd, int fullSync, int dataOnly){
  int rc;















  /* Record the number of times that we do a normal fsync() and 
  ** FULLSYNC.  This is used during testing to verify that this procedure
  ** gets called with the correct arguments.
  */
#ifdef SQLITE_TEST
  if( fullSync ) sqlite3_fullsync_count++;
................................................................................
#endif

  /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
  ** no-op
  */
#ifdef SQLITE_NO_SYNC
  rc = SQLITE_OK;
#else

#if HAVE_FULLFSYNC
  if( fullSync ){
    rc = fcntl(fd, F_FULLFSYNC, 0);
  }else{
    rc = 1;
  }
  /* If the FULLFSYNC failed, fall back to attempting an fsync().
   * It shouldn't be possible for fullfsync to fail on the local 
................................................................................
   * the fcntl call every time sync is called.
   */
  if( rc ) rc = fsync(fd);

#else 
  if( dataOnly ){
    rc = fdatasync(fd);
#if defined(__RTP__) || defined(_WRS_KERNEL)
    if( rc==-1 && errno==ENOTSUP ){
      rc = fsync(fd);
    }
#endif
  }else{
    rc = fsync(fd);
  }
#endif /* HAVE_FULLFSYNC */
#endif /* defined(SQLITE_NO_SYNC) */

#if defined(__RTP__) || defined(_WRS_KERNEL)
  if( rc!= -1 ){
    rc = 0;
  }
#endif

  return rc;
}

/*
** Make sure all writes to a particular file are committed to disk.
**
** If dataOnly==0 then both the file itself and its metadata (file
................................................................................
#endif /* SQLITE_ENABLE_LOCKING_STYLE */

/*
** The nolockLockingContext is void
*/
typedef void nolockLockingContext;

static int nolockCheckReservedLock(sqlite3_file *id, int *pResOut) {

  *pResOut = 0;
  return SQLITE_OK;
}

static int nolockLock(sqlite3_file *id, int locktype) {

  return SQLITE_OK;
}

static int nolockUnlock(sqlite3_file *id, int locktype) {

  return SQLITE_OK;
}

/*
** Close a file.
*/
static int nolockClose(sqlite3_file *id) {
#if defined(__RTP__) || defined(_WRS_KERNEL)
  int rc;
  enterMutex();
  rc = closeUnixFile(id);
  leaveMutex();
  return rc;
#else
  return closeUnixFile(id);
#endif
}


/*
** Information and control of an open file handle.
*/
static int unixFileControl(sqlite3_file *id, int op, void *pArg){
................................................................................
** larger for some devices.
**
** SQLite code assumes this function cannot fail. It also assumes that
** if two files are created in the same file-system directory (i.e.
** a database and its journal file) that the sector size will be the
** same for both.
*/
static int unixSectorSize(sqlite3_file *id){

  return SQLITE_DEFAULT_SECTOR_SIZE;
}

/*
** Return the device characteristics for the file. This is always 0.
*/
static int unixDeviceCharacteristics(sqlite3_file *id){

  return 0;
}

/*
** Initialize the contents of the unixFile structure pointed to by pId.
**
** When locking extensions are enabled, the filepath and locking style 
................................................................................
  return fillInUnixFile(pVfs, fd, dirfd, pFile, zPath, noLock, isDelete);
}

/*
** Delete the file at zPath. If the dirSync argument is true, fsync()
** the directory after deleting the file.
*/
static int unixDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){
  int rc = SQLITE_OK;

  SimulateIOError(return SQLITE_IOERR_DELETE);
  unlink(zPath);
#ifndef SQLITE_DISABLE_DIRSYNC
  if( dirSync ){
    int fd;
    rc = openDirectory(zPath, &fd);
    if( rc==SQLITE_OK ){
................................................................................
**     SQLITE_ACCESS_EXISTS: Return 1 if the file exists
**     SQLITE_ACCESS_READWRITE: Return 1 if the file is read and writable.
**     SQLITE_ACCESS_READONLY: Return 1 if the file is readable.
**
** Otherwise return 0.
*/
static int unixAccess(
  sqlite3_vfs *pVfs, 
  const char *zPath, 
  int flags, 
  int *pResOut
){
  int amode = 0;

  SimulateIOError( return SQLITE_IOERR_ACCESS; );
  switch( flags ){
    case SQLITE_ACCESS_EXISTS:
      amode = F_OK;
      break;
    case SQLITE_ACCESS_READWRITE:
      amode = W_OK|R_OK;
................................................................................

#ifndef SQLITE_OMIT_LOAD_EXTENSION
/*
** Interfaces for opening a shared library, finding entry points
** within the shared library, and closing the shared library.
*/
#include <dlfcn.h>
static void *unixDlOpen(sqlite3_vfs *pVfs, const char *zFilename){

  return dlopen(zFilename, RTLD_NOW | RTLD_GLOBAL);
}

/*
** SQLite calls this function immediately after a call to unixDlSym() or
** unixDlOpen() fails (returns a null pointer). If a more detailed error
** message is available, it is written to zBufOut. If no error message
** is available, zBufOut is left unmodified and SQLite uses a default
** error message.
*/
static void unixDlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){
  char *zErr;

  enterMutex();
  zErr = dlerror();
  if( zErr ){
    sqlite3_snprintf(nBuf, zBufOut, "%s", zErr);
  }
  leaveMutex();
}
static void *unixDlSym(sqlite3_vfs *pVfs, void *pHandle, const char *zSymbol){

  return dlsym(pHandle, zSymbol);
}
static void unixDlClose(sqlite3_vfs *pVfs, void *pHandle){

  dlclose(pHandle);
}
#else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
  #define unixDlOpen  0
  #define unixDlError 0
  #define unixDlSym   0
  #define unixDlClose 0
#endif

/*
** Write nBuf bytes of random data to the supplied buffer zBuf.
*/
static int unixRandomness(sqlite3_vfs *pVfs, int nBuf, char *zBuf){

  assert((size_t)nBuf>=(sizeof(time_t)+sizeof(int)));

  /* We have to initialize zBuf to prevent valgrind from reporting
  ** errors.  The reports issued by valgrind are incorrect - we would
  ** prefer that the randomness be increased by making use of the
  ** uninitialized space in zBuf - but valgrind errors tend to worry
  ** some users.  Rather than argue, it seems easier just to initialize
................................................................................
** Sleep for a little while.  Return the amount of time slept.
** The argument is the number of microseconds we want to sleep.
** The return value is the number of microseconds of sleep actually
** requested from the underlying operating system, a number which
** might be greater than or equal to the argument, but not less
** than the argument.
*/
static int unixSleep(sqlite3_vfs *pVfs, int microseconds){
#if defined(__RTP__) || defined(_WRS_KERNEL)
  struct timespec sp;

  sp.tv_sec = microseconds / 1000000;
  sp.tv_nsec = (microseconds % 1000000) * 1000;
  nanosleep(&sp, NULL);
#else
#if defined(HAVE_USLEEP) && HAVE_USLEEP
  usleep(microseconds);
  return microseconds;
#else
  int seconds = (microseconds+999999)/1000000;
  sleep(seconds);
  return seconds*1000000;
#endif
#endif
}

/*
** The following variable, if set to a non-zero value, becomes the result
** returned from sqlite3OsCurrentTime().  This is used for testing.
*/
#ifdef SQLITE_TEST
................................................................................
#endif

/*
** Find the current time (in Universal Coordinated Time).  Write the
** current time and date as a Julian Day number into *prNow and
** return 0.  Return 1 if the time and date cannot be found.
*/
static int unixCurrentTime(sqlite3_vfs *pVfs, double *prNow){
#if defined(__RTP__) || defined(_WRS_KERNEL)
  struct timespec sNow;
  clock_gettime(CLOCK_REALTIME, &sNow);
  *prNow = 2440587.5 + sNow.tv_sec/86400.0 + sNow.tv_nsec/86400000000000.0;
#else
#ifdef NO_GETTOD
  time_t t;
  time(&t);
  *prNow = t/86400.0 + 2440587.5;
#else
  struct timeval sNow;
  gettimeofday(&sNow, 0);
  *prNow = 2440587.5 + sNow.tv_sec/86400.0 + sNow.tv_usec/86400000000.0;
#endif
#endif
#ifdef SQLITE_TEST
  if( sqlite3_current_time ){
    *prNow = sqlite3_current_time/86400.0 + 2440587.5;
  }
#endif

  return 0;
}

static int unixGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){



  return 0;
}

/*
** Initialize the operating system interface.
*/
int sqlite3_os_init(void){ 







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**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
******************************************************************************
**
** This file contains code that is specific to Unix systems.
**
** $Id: os_unix.c,v 1.213 2008/11/19 11:35:40 danielk1977 Exp $
*/
#include "sqliteInt.h"
#if SQLITE_OS_UNIX              /* This file is used on unix only */

/*
** If SQLITE_ENABLE_LOCKING_STYLE is defined and is non-zero, then several
** alternative locking implementations are provided:
................................................................................
#  if defined(__DARWIN__)
#    define SQLITE_ENABLE_LOCKING_STYLE 1
#  else
#    define SQLITE_ENABLE_LOCKING_STYLE 0
#  endif
#endif

/*
** Define the IS_VXWORKS pre-processor macro to 1 if building on 
** vxworks, or 0 otherwise.
*/
#if defined(__RTP__) || defined(_WRS_KERNEL)
#  define IS_VXWORKS 1
#else
#  define IS_VXWORKS 0
#endif

/*
** These #defines should enable >2GB file support on Posix if the
** underlying operating system supports it.  If the OS lacks
** large file support, these should be no-ops.
**
** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
** on the compiler command line.  This is necessary if you are compiling
................................................................................
** for testing when we want to run through the test suite quickly.
** You are strongly advised *not* to deploy with SQLITE_NO_SYNC
** enabled, however, since with SQLITE_NO_SYNC enabled, an OS crash
** or power failure will likely corrupt the database file.
*/
static int full_fsync(int fd, int fullSync, int dataOnly){
  int rc;

  /* The following "ifdef/elif/else/" block has the same structure as
  ** the one below. It is replicated here solely to avoid cluttering 
  ** up the real code with the UNUSED_PARAMETER() macros.
  */
#ifdef SQLITE_NO_SYNC
  UNUSED_PARAMETER(fd);
  UNUSED_PARAMETER(fullSync);
  UNUSED_PARAMETER(dataOnly);
#elif HAVE_FULLFSYNC
  UNUSED_PARAMETER(fullSync);
#else
  UNUSED_PARAMETER(dataOnly);
#endif

  /* Record the number of times that we do a normal fsync() and 
  ** FULLSYNC.  This is used during testing to verify that this procedure
  ** gets called with the correct arguments.
  */
#ifdef SQLITE_TEST
  if( fullSync ) sqlite3_fullsync_count++;
................................................................................
#endif

  /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
  ** no-op
  */
#ifdef SQLITE_NO_SYNC
  rc = SQLITE_OK;


#elif HAVE_FULLFSYNC
  if( fullSync ){
    rc = fcntl(fd, F_FULLFSYNC, 0);
  }else{
    rc = 1;
  }
  /* If the FULLFSYNC failed, fall back to attempting an fsync().
   * It shouldn't be possible for fullfsync to fail on the local 
................................................................................
   * the fcntl call every time sync is called.
   */
  if( rc ) rc = fsync(fd);

#else 
  if( dataOnly ){
    rc = fdatasync(fd);

    if( IS_VXWORKS && rc==-1 && errno==ENOTSUP ){
      rc = fsync(fd);
    }

  }else{
    rc = fsync(fd);
  }
#endif /* ifdef SQLITE_NO_SYNC elif HAVE_FULLFSYNC */



  if( IS_VXWORKS && rc!= -1 ){
    rc = 0;
  }


  return rc;
}

/*
** Make sure all writes to a particular file are committed to disk.
**
** If dataOnly==0 then both the file itself and its metadata (file
................................................................................
#endif /* SQLITE_ENABLE_LOCKING_STYLE */

/*
** The nolockLockingContext is void
*/
typedef void nolockLockingContext;

static int nolockCheckReservedLock(sqlite3_file *NotUsed, int *pResOut){
  UNUSED_PARAMETER(NotUsed);
  *pResOut = 0;
  return SQLITE_OK;
}

static int nolockLock(sqlite3_file *NotUsed, int NotUsed2){
  UNUSED_PARAMETER2(NotUsed, NotUsed2);
  return SQLITE_OK;
}

static int nolockUnlock(sqlite3_file *NotUsed, int NotUsed2){
  UNUSED_PARAMETER2(NotUsed, NotUsed2);
  return SQLITE_OK;
}

/*
** Close a file.
*/
static int nolockClose(sqlite3_file *id) {

  int rc;
  if( IS_VXWORKS ) enterMutex();
  rc = closeUnixFile(id);
  if( IS_VXWORKS ) leaveMutex();
  return rc;



}


/*
** Information and control of an open file handle.
*/
static int unixFileControl(sqlite3_file *id, int op, void *pArg){
................................................................................
** larger for some devices.
**
** SQLite code assumes this function cannot fail. It also assumes that
** if two files are created in the same file-system directory (i.e.
** a database and its journal file) that the sector size will be the
** same for both.
*/
static int unixSectorSize(sqlite3_file *NotUsed){
  UNUSED_PARAMETER(NotUsed);
  return SQLITE_DEFAULT_SECTOR_SIZE;
}

/*
** Return the device characteristics for the file. This is always 0 for unix.
*/
static int unixDeviceCharacteristics(sqlite3_file *NotUsed){
  UNUSED_PARAMETER(NotUsed);
  return 0;
}

/*
** Initialize the contents of the unixFile structure pointed to by pId.
**
** When locking extensions are enabled, the filepath and locking style 
................................................................................
  return fillInUnixFile(pVfs, fd, dirfd, pFile, zPath, noLock, isDelete);
}

/*
** Delete the file at zPath. If the dirSync argument is true, fsync()
** the directory after deleting the file.
*/
static int unixDelete(sqlite3_vfs *NotUsed, const char *zPath, int dirSync){
  int rc = SQLITE_OK;
  UNUSED_PARAMETER(NotUsed);
  SimulateIOError(return SQLITE_IOERR_DELETE);
  unlink(zPath);
#ifndef SQLITE_DISABLE_DIRSYNC
  if( dirSync ){
    int fd;
    rc = openDirectory(zPath, &fd);
    if( rc==SQLITE_OK ){
................................................................................
**     SQLITE_ACCESS_EXISTS: Return 1 if the file exists
**     SQLITE_ACCESS_READWRITE: Return 1 if the file is read and writable.
**     SQLITE_ACCESS_READONLY: Return 1 if the file is readable.
**
** Otherwise return 0.
*/
static int unixAccess(
  sqlite3_vfs *NotUsed, 
  const char *zPath, 
  int flags, 
  int *pResOut
){
  int amode = 0;
  UNUSED_PARAMETER(NotUsed);
  SimulateIOError( return SQLITE_IOERR_ACCESS; );
  switch( flags ){
    case SQLITE_ACCESS_EXISTS:
      amode = F_OK;
      break;
    case SQLITE_ACCESS_READWRITE:
      amode = W_OK|R_OK;
................................................................................

#ifndef SQLITE_OMIT_LOAD_EXTENSION
/*
** Interfaces for opening a shared library, finding entry points
** within the shared library, and closing the shared library.
*/
#include <dlfcn.h>
static void *unixDlOpen(sqlite3_vfs *NotUsed, const char *zFilename){
  UNUSED_PARAMETER(NotUsed);
  return dlopen(zFilename, RTLD_NOW | RTLD_GLOBAL);
}

/*
** SQLite calls this function immediately after a call to unixDlSym() or
** unixDlOpen() fails (returns a null pointer). If a more detailed error
** message is available, it is written to zBufOut. If no error message
** is available, zBufOut is left unmodified and SQLite uses a default
** error message.
*/
static void unixDlError(sqlite3_vfs *NotUsed, int nBuf, char *zBufOut){
  char *zErr;
  UNUSED_PARAMETER(NotUsed);
  enterMutex();
  zErr = dlerror();
  if( zErr ){
    sqlite3_snprintf(nBuf, zBufOut, "%s", zErr);
  }
  leaveMutex();
}
static void *unixDlSym(sqlite3_vfs *NotUsed, void *pHandle, const char*zSymbol){
  UNUSED_PARAMETER(NotUsed);
  return dlsym(pHandle, zSymbol);
}
static void unixDlClose(sqlite3_vfs *NotUsed, void *pHandle){
  UNUSED_PARAMETER(NotUsed);
  dlclose(pHandle);
}
#else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
  #define unixDlOpen  0
  #define unixDlError 0
  #define unixDlSym   0
  #define unixDlClose 0
#endif

/*
** Write nBuf bytes of random data to the supplied buffer zBuf.
*/
static int unixRandomness(sqlite3_vfs *NotUsed, int nBuf, char *zBuf){
  UNUSED_PARAMETER(NotUsed);
  assert((size_t)nBuf>=(sizeof(time_t)+sizeof(int)));

  /* We have to initialize zBuf to prevent valgrind from reporting
  ** errors.  The reports issued by valgrind are incorrect - we would
  ** prefer that the randomness be increased by making use of the
  ** uninitialized space in zBuf - but valgrind errors tend to worry
  ** some users.  Rather than argue, it seems easier just to initialize
................................................................................
** Sleep for a little while.  Return the amount of time slept.
** The argument is the number of microseconds we want to sleep.
** The return value is the number of microseconds of sleep actually
** requested from the underlying operating system, a number which
** might be greater than or equal to the argument, but not less
** than the argument.
*/
static int unixSleep(sqlite3_vfs *NotUsed, int microseconds){
#if defined(__RTP__) || defined(_WRS_KERNEL)
  struct timespec sp;

  sp.tv_sec = microseconds / 1000000;
  sp.tv_nsec = (microseconds % 1000000) * 1000;
  nanosleep(&sp, NULL);
  return microseconds;
#elif defined(HAVE_USLEEP) && HAVE_USLEEP
  usleep(microseconds);
  return microseconds;
#else
  int seconds = (microseconds+999999)/1000000;
  sleep(seconds);
  return seconds*1000000;
#endif
  UNUSED_PARAMETER(NotUsed);
}

/*
** The following variable, if set to a non-zero value, becomes the result
** returned from sqlite3OsCurrentTime().  This is used for testing.
*/
#ifdef SQLITE_TEST
................................................................................
#endif

/*
** Find the current time (in Universal Coordinated Time).  Write the
** current time and date as a Julian Day number into *prNow and
** return 0.  Return 1 if the time and date cannot be found.
*/
static int unixCurrentTime(sqlite3_vfs *NotUsed, double *prNow){
#if defined(__RTP__) || defined(_WRS_KERNEL)
  struct timespec sNow;
  clock_gettime(CLOCK_REALTIME, &sNow);
  *prNow = 2440587.5 + sNow.tv_sec/86400.0 + sNow.tv_nsec/86400000000000.0;

#elif defined(NO_GETTOD)
  time_t t;
  time(&t);
  *prNow = t/86400.0 + 2440587.5;
#else
  struct timeval sNow;
  gettimeofday(&sNow, 0);
  *prNow = 2440587.5 + sNow.tv_sec/86400.0 + sNow.tv_usec/86400000000.0;
#endif

#ifdef SQLITE_TEST
  if( sqlite3_current_time ){
    *prNow = sqlite3_current_time/86400.0 + 2440587.5;
  }
#endif
  UNUSED_PARAMETER(NotUsed);
  return 0;
}

static int unixGetLastError(sqlite3_vfs *NotUsed, int NotUsed2, char *NotUsed3){
  UNUSED_PARAMETER(NotUsed);
  UNUSED_PARAMETER(NotUsed2);
  UNUSED_PARAMETER(NotUsed3);
  return 0;
}

/*
** Initialize the operating system interface.
*/
int sqlite3_os_init(void){