Files
privacore-open-source-searc…/BigFile.h
2016-08-31 11:13:31 +02:00

326 lines
10 KiB
C++

// Copyright Sep 2000 Matt Wells
// . this class makes the 2gb file limit transparent
// . you can actually set you own file size limit to whatever you want as
// int32_t as it's greater than zero
// . this is usually 2gb
// . TODO: fix the O_SYNC option
// . TODO: provide ability to pass flags
#ifndef GB_BIGFILE_H
#define GB_BIGFILE_H
#include "File.h"
#include "JobScheduler.h" //for job_exit_t
#include "SafeBuf.h"
#ifndef PRIVACORE_TEST_VERSION
// . use 512 disk megs per part file
// . at a GB_PAGE_SIZE of 16k this is 32k RdbMap pages (512k) per part file
// . let's use 2GB now to conserve file descriptors
#define MAX_PART_SIZE (1920LL*1024LL*1024LL)
#else
#define MAX_PART_SIZE (20LL*1024LL*1024LL)
#endif
#define LITTLEBUFSIZE sizeof(File)
class FileState {
public:
// callback must be top 4 bytes of the state class we give to g_loop
// callback must be first X bytes
class BigFile *m_bigfile;
char *m_buf;
int64_t m_bytesToGo;
int64_t m_offset;
// . the original offset, because we set m_offset to m_currentOffset
// if the original offset specified is -1
// . we also advance BigFile::m_currentOffset when done w/ read/write
//int64_t m_origOffset;
bool m_doWrite;
int64_t m_bytesDone;
void *m_state ;
void (*m_callback) ( void *state ) ;
// goes from 0 to 1, the lower the niceness, the higher the priority
int32_t m_niceness;
// was it found in the disk page cache?
char m_inPageCache;
// . we get our fds before starting the read thread to avoid
// problems with accessing m_files since RdbMerge may call unlinkPart
// from the main thread while we're trying to get these things
// . no read should span more than 2 file descriptors
int32_t m_filenum1;
int32_t m_filenum2;
int m_fd1 ;
int m_fd2 ;
char m_filename1[1024];
char m_filename2[1024];
// hold the errno from the threaded read/write here
int32_t m_errno;
// when we started for graphing purposes (in milliseconds)
int64_t m_startTime;
int64_t m_doneTime;
// it is
// a "virtual fd" for this whole file
int64_t m_vfd;
// for avoiding unlink/reopens while doing a threaded read
int32_t m_closeCount1 ;
int32_t m_closeCount2 ;
int32_t m_flags;
// when we are given a NULL buffer to read into we must allocate
// in Threads.cpp right before the
// thread is launched. this will stop us from having 19000 unlaunched
// threads each hogging up 32KB of memory waiting to read tfndb.
// m_allocBuf points to what we allocated.
char *m_allocBuf;
int64_t m_allocSize;
// m_allocOff is offset into m_allocBuf where we start reading into
// from the file
int64_t m_allocOff;
};
class BigFile {
public:
~BigFile();
BigFile();
// . set a big file's name
// . we split little files that make up this BigFile between
// "dir" and "stripeDir"
bool set ( const char *dir, const char *baseFilename, const char *stripeDir = NULL );
// self explanatory
bool doesExist ( ) ;
// does file part #n exist?
bool doesPartExist ( int32_t n ) ;
// . does not actually open any part file we have
// . waits for a read/write operation before doing that
// . if you set maxFileSize to -1 we set it to BigFile::getFileSize()
// . if you are opening a new file for writing, you need to provide it
bool open(int flags);
void logAllData(int32_t log_type);
int getFlags() { return m_flags; }
void setBlocking ( ) { m_flags &= ~((int32_t)O_NONBLOCK); }
void setNonBlocking ( ) { m_flags |= O_NONBLOCK ; }
// . return -2 on error
// . return -1 if does not exist
// . otherwise return the big file's complete file size (can b >2gb)
int64_t getFileSize ( );
int64_t getSize ( ) { return getFileSize(); }
// use the base filename as our filename
char *getFilename() { return m_baseFilename.getBufStart(); }
const char *getFilename() const { return m_baseFilename.getBufStart(); }
char *getDir() { return m_dir.getBufStart(); }
// . returns false if blocked, true otherwise
// . sets g_errno on error
// . otherwise, returns 1 if the read was completed
// . decides what 2gb part file(s) we should read from
bool read ( void *buf ,
int64_t size ,
int64_t offset ,
FileState *fs = NULL ,
void *state = NULL ,
void (* callback)(void *state) = NULL ,
int32_t niceness = 1 ,
bool allowPageCache = true ,
bool hitDisk = true ,
int32_t allocOff = 0 );
// . returns false if blocked, true otherwise
// . sets g_errno on error
// . IMPORTANT: if returns -1 it MAY have written some bytes
// successfully to OTHER parts that's why caller should be
// responsible for maintaining current write offset
bool write ( void *buf ,
int64_t size ,
int64_t offset ,
FileState *fs = NULL ,
void *state = NULL ,
void (* callback)(void *state) = NULL ,
int32_t niceness = 1 ,
bool allowPageCache = true );
// unlinks all part files
bool unlink ( );
// . renames ALL parts too
// . doesn't change directory, just the base filename
// . use m_dir if newBaseFilenameDir is NULL
// . force = rename even if newFile exist
bool rename ( const char *newBaseFilename, const char *newBaseFilenameDir=NULL, bool force=false ) ;
bool move ( const char *newDir );
// . returns false and sets g_errno on failure
// . chop only parts LESS THAN "part"
bool unlinkPart ( int32_t part );
// . these here all use threads and call your callback when done
// . they return false if blocked, true otherwise
// . they set g_errno on error
bool unlink ( void (* callback) ( void *state ) ,
void *state ) ;
bool rename ( const char *newBaseFilename, void (* callback) ( void *state ) , void *state, bool force=false ) ;
bool unlinkPart ( int32_t part , void (* callback) ( void *state ) , void *state ) ;
// closes all part files
bool close ();
// just close all the fds of the part files, used by RdbMap.cpp.
bool closeFds ( ) ;
// what part (little File) of this BigFile has offset "offset"?
int getPartNum ( int64_t offset ) { return offset / MAX_PART_SIZE; }
// . opens the nth file if necessary to get it's fd
// . returns -1 if none, >=0 on success
int getfd ( int32_t n , bool forReading );//, int32_t *vfd = NULL );
int32_t getVfd ( ) { return m_vfd; }
// WARNING: some may have been unlinked from call to unlinkPart()
int32_t getNumParts ( ) { return m_numParts; }
private:
// makes the filename of part file #n
void makeFilename_r ( char *baseFilename ,
char *baseFilenameDir ,
int32_t n ,
char *buf ,
int32_t maxBufSize );
void removePart ( int32_t i ) ;
// don't launch a threaded rename/unlink if one already in progress
// since we only have one callback, m_callback
int32_t m_numThreads;
void (*m_callback)(void *state);
void *m_state;
// is the threaded op an unlink? (or rename?)
bool m_isUnlink;
int32_t m_part; // part # to unlink (-1 for all)
// number of parts remaining to be unlinked/renamed
int32_t m_partsRemaining;
char m_tinyBuf[8];
// to hold the array of Files
SafeBuf m_filePtrsBuf;
// enough mem for our first File so we can avoid a malloc
char m_littleBuf[LITTLEBUFSIZE];
// . wrapper for all reads and writes
// . if doWrite is true then we'll do a write, otherwise we do a read
// . returns false and sets errno on error, true on success
bool readwrite ( void *buf,
int64_t size,
int64_t offset,
bool doWrite,
FileState *fstate ,
void *state ,
void (* callback) ( void *state ) ,
int32_t niceness ,
bool allowPageCache ,
bool hitDisk ,
int32_t allocOff );
// . returns false if blocked, true otherwise
// . sets g_errno on error
bool unlinkRename ( const char *newBaseFilename,
int32_t part ,
bool useThread ,
void (* callback) ( void *state ) ,
void *state ,
const char *newBaseFilenameDir = NULL,
bool force = false );
//job/thread worker functions helping unlinkrename()
static void renameWrapper(void *state);
static void doneRenameWrapper(void *state, job_exit_t exit_type);
void doneRenameWrapper(File *f);
void renameWrapper(File *f, int32_t i);
static void unlinkWrapper(void *state);
void unlinkWrapper(File *f);
static void doneUnlinkWrapper(void *state, job_exit_t exit_type);
void doneUnlinkWrapper(File *f, int32_t i);
// . add all parts from this directory
// . called by set() above for normal dir as well as stripe dir
bool addParts ( const char *dirname ) ;
bool addPart ( int32_t n ) ;
// for basefilename to avoid an alloc
char m_tmpBaseBuf[32];
//int32_t m_permissions;
int32_t m_flags;
int32_t m_vfd;
// our most important the directory and filename
SafeBuf m_dir ;
SafeBuf m_baseFilename ;
// rename stores the new name here so we can rename the m_files[i]
// after the rename has completed and the rename thread returns
SafeBuf m_newBaseFilename ;
// if first char in this dir is 0 then use m_dir
SafeBuf m_newBaseFilenameDir ;
public:
File *getFile2 ( int32_t n ) {
if ( n >= m_maxParts ) return NULL;
File **filePtrs = (File **)m_filePtrsBuf.getBufStart();
File *f = filePtrs[n];
//if ( ! f ->calledSet() ) return NULL;
// this will be NULL if addPart(n) never called
return f;
}
bool reset ( );
// determined in open() override
int m_numParts;
// maximum part #
int32_t m_maxParts;
// prevent circular calls to BigFile::close() with this
bool m_isClosing;
int64_t m_fileSize;
// oldest of the last modified dates of all the part files
time_t m_lastModified;
time_t getLastModifiedTime();
};
extern int32_t g_unlinkRenameThreads;
#endif // GB_BIGFILE_H