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cdesktop/cde/programs/dtinfo/DtMmdb/storage/page_storage.C
2018-04-28 12:30:20 -06:00

1356 lines
32 KiB
C

/*
* CDE - Common Desktop Environment
*
* Copyright (c) 1993-2012, The Open Group. All rights reserved.
*
* These libraries and programs are free software; you can
* redistribute them and/or modify them under the terms of the GNU
* Lesser General Public License as published by the Free Software
* Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* These libraries and programs are distributed in the hope that
* they will be useful, but WITHOUT ANY WARRANTY; without even the
* implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
* PURPOSE. See the GNU Lesser General Public License for more
* details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with these libraries and programs; if not, write
* to the Free Software Foundation, Inc., 51 Franklin Street, Fifth
* Floor, Boston, MA 02110-1301 USA
*/
/*
* $XConsortium: page_storage.C /main/8 1996/10/04 10:49:57 drk $
*
* Copyright (c) 1992 HAL Computer Systems International, Ltd.
* All rights reserved. Unpublished -- rights reserved under
* the Copyright Laws of the United States. USE OF A COPYRIGHT
* NOTICE IS PRECAUTIONARY ONLY AND DOES NOT IMPLY PUBLICATION
* OR DISCLOSURE.
*
* THIS SOFTWARE CONTAINS CONFIDENTIAL INFORMATION AND TRADE
* SECRETS OF HAL COMPUTER SYSTEMS INTERNATIONAL, LTD. USE,
* DISCLOSURE, OR REPRODUCTION IS PROHIBITED WITHOUT THE
* PRIOR EXPRESS WRITTEN PERMISSION OF HAL COMPUTER SYSTEMS
* INTERNATIONAL, LTD.
*
* RESTRICTED RIGHTS LEGEND
* Use, duplication, or disclosure by the Government is subject
* to the restrictions as set forth in subparagraph (c)(l)(ii)
* of the Rights in Technical Data and Computer Software clause
* at DFARS 252.227-7013.
*
* HAL COMPUTER SYSTEMS INTERNATIONAL, LTD.
* 1315 Dell Avenue
* Campbell, CA 95008
*
*/
#include "storage/page.h"
#include "storage/page_storage.h"
#include "storage/version.h"
#include "utility/db_version.h"
#define db_type "MMDB"
#define db_type_sz strlen(db_type)
#define db_order_sz sizeof(char)
int page_storage::dv_sz = 0;
int page_storage::abs_off = 0;
#ifndef C_API
page_cache_global_part page_storage::f_global_pcache;
#else
page_cache_global_part* page_storage::f_global_pcache_ptr = 0;
#endif
static char* db_version = 0;
static char* data_version = 0;
str_index_record_t::str_index_record_t(int offset, mmdb_pos_t lc)
: str_offset(offset), loc(lc)
{
}
void delete_str_index_record(const void* t)
{
delete ((str_index_record_t*)t);
}
extern void_ptr_array g_store_array;
extern Boolean g_transaction_on;
//////////////////////////////
//
//////////////////////////////
store_trans::store_trans(char* p, char* n, int psz) :
path(p), name(n), status(DISABLED),
log_store(0), log_index(0), max_pages(0), page_sz(psz)
{
}
store_trans::~store_trans()
{
/*
MESSAGE(cerr, "dstr store_trans object");
debug(cerr, status);
debug(cerr, DISABLED);
debug(cerr, int(log_store));
*/
if ( status == DISABLED && log_store ) {
delete log_store;
del_file(form("%s.log", name), path);
}
delete log_index;
}
void store_trans::init(rep_policy* policy)
{
if ( log_store == 0 ) {
log_store = new unixf_storage(path, form("%s.log", name), policy);
if ( ! (*log_store) )
throw(streamException(log_store -> rdstate()));
}
if ( log_index == 0 ) {
log_index = new imp_die;
}
}
void store_trans::quit()
{
if ( log_store )
log_store -> truncate(0);
if ( log_index )
log_index -> clean();
}
///////////////////////////////////
// Constructor
///////////////////////////////////
page_storage::page_storage( char* _path, char* _name,
unixf_storage* store, int pg_sz,
int/*no_pages*/, mmdb_byte_order_t create_order) :
abs_storage(_path, _name, PAGE_STORAGE_CODE),
trans_info(page_storage::path, page_storage::name, pg_sz),
page_sz(pg_sz),
f_local_pcache(30),
v_db_order(create_order), v_buf(0),
pagings(0),
total_page_access(0)
{
//debug(cerr, my_name());
//debug(cerr, (void*)this);
//#ifdef C_API
if ( dv_sz == 0 ) {
dv_sz = db_type_sz + mm_version::version_bytes() + db_order_sz;
abs_off = dv_sz;
}
//#endif
storage_ptr = store;
int bts = ((unixf_storage*)storage_ptr) -> bytes();
v_server_order = byte_order();
//debug(cerr, v_server_order);
if ( bts == 0 ) {
//////////////////////
// empty store file
//////////////////////
if ( db_version == 0 ) {
db_version = new char[dv_sz];
memcpy(db_version, db_type, db_type_sz);
mm_version x(MAJOR, MINOR);
x.to_byte_string(db_version+db_type_sz,
(v_db_order != v_server_order) ? true : false
);
char z = v_db_order;
memcpy(db_version+db_type_sz+mm_version::version_bytes(),
&z, db_order_sz);
}
storage_ptr -> updateString( 0, db_version, dv_sz, 0, true);
v_swap_order = (v_db_order != v_server_order) ? true : false;
} else {
///////////////////
// store exists.
///////////////////
bts -= abs_off;
if ( data_version == 0 ) {
data_version = new char[dv_sz];
}
storage_ptr -> readString(0, data_version, dv_sz);
/////////////////////////////////
// "MMDB" magic number testing
/////////////////////////////////
if ( memcmp(data_version, db_type, db_type_sz) != 0 ) {
throw(stringException(
form("bad magic number. corrupted store %s/%s", _path, _name)
)
);
}
///////////////////////////////
// get db byte order
///////////////////////////////
char z;
memcpy(&z,
data_version + db_type_sz + mm_version::version_bytes(),
db_order_sz
);
v_db_order = int(z);
if ( v_db_order != mmdb_big_endian && v_db_order != mmdb_little_endian ) {
debug(cerr, v_db_order);
throw(stringException(
"data is in neither big endian nor little endian format"
));
}
///////////////////////////////
// test version
///////////////////////////////
v_swap_order = (v_db_order != v_server_order) ? true : false;
mm_version dv(data_version+db_type_sz, v_swap_order);
f_version = dv;
mm_version cv(MAJOR, MINOR);
if ( cv < dv ) {
cerr << "code major = " << cv.major_version() << "\n";
cerr << "code minor = " << cv.minor_version() << "\n";
cerr << "data major = " << dv.major_version() << "\n";
cerr << "data minor = " << dv.minor_version() << "\n";
throw(stringException(
form("data and code version mismatch on store %s/%s", _path, _name)
)
);
}
}
//debug(cerr, v_db_order);
total_pages = bts / page_sz;
f_local_pcache.init_heap(this);
set_mode(HEALTH, true);
}
/***********************************************************/
// Destructor
/***********************************************************/
page_storage::~page_storage()
{
//MESSAGE(cerr, "dstr page_storage");
//debug(cerr, my_name());
delete v_buf;
delete storage_ptr;
delete data_version;
data_version = 0;
delete db_version;
db_version = 0;
f_local_pcache.quit_heap(this);
f_global_pcache.remove_pages(this);
/*
MESSAGE(cerr, my_name());
debug(cerr, total_page_access);
debug(cerr, pagings);
debug(cerr, float(pagings)/total_page_access);
*/
}
void page_storage::remove()
{
storage_ptr -> remove();
}
void page_storage::sync()
{
/*
MESSAGE(cerr, "page_storage::sync()");
debug(cerr, my_path());
debug(cerr, my_name());
debug(cerr, pages());
debug(cerr, int(this));
*/
long ind = f_global_pcache.f_replace_policy.first();
while ( ind != 0 ) {
lru_page *p= (lru_page*)(f_global_pcache.f_replace_policy)(ind, ACTIVE);
if ( p -> f_store == this )
sync( p );
f_global_pcache.f_replace_policy.next(ind);
}
//MESSAGE(cerr, "page_storage::sync() done");
}
void page_storage::sync( int page_num )
{
sync((*this)(page_num, READ));
}
void page_storage::sync( page* p )
{
if ( p == 0 || p -> page_id() <= 0 ) {
throw(stringException("null page pointer"));
}
if ( p -> dirty == true ) {
//cerr << "dirty PAGE swapped out " << p -> page_id();
//cerr << " " << my_name() << "\n";
int offset = ( p -> page_id() - 1 ) * page_sz ;
#ifdef PORTABLE_DB
p -> _swap_order(false);
#endif
//debug(cerr, *p);
#ifdef DEBUG
fprintf(stderr, "purging page at %p size=%d into %s/%s @ %s:%d\n",
p -> page_base(), page_sz,
storage_ptr->my_path(), storage_ptr->my_name(),
__FILE__, __LINE__);
#endif
storage_ptr -> updateString( abs_off + mmdb_pos_t(offset),
p -> page_base(),
page_sz, 0, true
);
#ifdef PORTABLE_DB
//////////////////////////////////////////////////////////////
// flip back to original. as the server will not quit after
// the sync.
//////////////////////////////////////////////////////////////
p -> _swap_order(true);
#endif
p -> dirty = false;
}
}
//static Boolean xflag = false;
/***********************************************************/
// readString().
/***********************************************************/
int
page_storage::readString(mmdb_pos_t loc, char* base, int len, int str_offset)
{
/*
int xstring_ofst = str_offset;
int xloc = loc;
int xlen = len;
MESSAGE(cerr, "page_storage: readString");
debug(cerr, my_path());
debug(cerr, my_name());
debug(cerr, loc);
debug(cerr, int(base));
debug(cerr, len);
debug(cerr, str_offset);
*/
buffer in_cache(0);
in_cache.set_chunk(base, len);
spointer_t *slot_info;
while ( len > 0 ) {
if ( loc == 0 ) {
throw(stringException("damaged store."));
}
int page_num = PAGE_ID( loc, page_sz );
int page_slot = PAGE_IDX( loc, page_sz );
//debug(cerr, page_num);
//debug(cerr, page_slot);
page *y = (*this)(page_num, READ);
slot_info = y -> get_spointer(page_slot);
int str_leng = slot_info -> string_leng();
loc = slot_info -> forward_ptr();
/*
MESSAGE(cerr, "slot info:");
debug(cerr, str_leng);
debug(cerr, loc);
debug(cerr, slot_info -> string_ofst());
*/
delete slot_info;
if ( str_offset >= str_leng ) {
str_offset -= str_leng;
} else {
int bytes_read = MIN(len, str_leng - str_offset);
/*
debug(cerr, len);
debug(cerr, bytes_read);
*/
y -> get( page_slot, in_cache, str_offset, bytes_read );
len -= bytes_read;
str_offset = 0;
}
}
//MESSAGE(cerr, "page_storage:: readString done");
return 0;
}
int
page_storage::get_str_ptr(mmdb_pos_t loc, char*& str,
int& len)
{
int page_num = PAGE_ID( loc, page_sz );
int page_slot = PAGE_IDX( loc, page_sz );
//MESSAGE(cerr, "IN get_str_ptr()");
//debug(cerr, my_path());
//debug(cerr, my_name());
//debug(cerr, page_num);
//debug(cerr, page_slot);
page *y = (*this)(page_num, READ);
spointer_t* slot_info = y -> get_spointer(page_slot);
//debug(cerr, int(slot_info -> get_mode(spointer_t::DELETED)));
/*
if ( page_num == 1 && page_slot == 1 ) {
debug(cerr, hex(slot_info -> header.int_view));
debug(cerr, hex(slot_info -> header.bit_view.spointer));
debug(cerr, hex(slot_info -> header.bit_view.length));
debug(cerr, hex(slot_info -> header.bit_view.deleted));
debug(cerr, hex(slot_info -> header.bit_view.first_recd));
debug(cerr, hex(slot_info -> header.bit_view.updated));
debug(cerr, hex(slot_info -> header.bit_view.is_object));
}
*/
if ( slot_info -> get_mode(spointer_t::DELETED) == true ) {
delete slot_info;
throw(stringException("read deleted byte string"));
}
delete slot_info;
y -> get_str_ptr(page_slot, str, len);
return 0;
}
int page_storage::insertString(mmdb_pos_t& loc, const char* base, int len, Boolean flush_opt)
{
/*
cerr << "insert: len=" << len << "\n";
int u3 = len;
*/
#ifdef STORAGE_DEBUG
MESSAGE(cerr, "page_storage insertString");
debug(cerr, len);
#endif
buffer temp_buf(0);
int page_num = 0;
int page_oft = 0;
int str_offset = len;
int sec_len;
Boolean first_recd = true;
Boolean new_page;
while ( str_offset > 0 ) {
loc = (page_num != 0 ) ?
FORM_PAGE_REF(page_num, page_oft, page_sz) :
0;
fbytes_t* v = f_local_pcache.find_host_page(this, new_page) ;
page_num = v -> page_num;
page* y = (*this)(page_num, WRITE);
sec_len = MIN(len, y -> free_bytes());
str_offset -= sec_len;
temp_buf.set_chunk((char*)(base + str_offset), sec_len);
temp_buf.set_content_sz(sec_len);
y -> put( page_oft, temp_buf );
spointer_t *x = y -> get_spointer(page_oft);
x -> set_mode(spointer_t::FIRST_RECD, first_recd);
x -> set_forward_ptr(loc);
delete x;
v -> free_bytes = y -> free_bytes();
f_local_pcache.adjust_heap(v, new_page);
if ( flush_opt == true ) sync(page_num);
first_recd = false;
len -= sec_len;
}
#ifdef STORAGE_DEBUG
MESSAGE(cerr, "FINAL LOC COMPONENT");
debug(cerr, page_oft);
debug(cerr, page_sz);
debug(cerr, page_num);
#endif
loc = FORM_PAGE_REF(page_num, page_oft, page_sz);
/*
int u1 = PAGE_ID( loc, page_sz );
int u2 = PAGE_IDX( loc, page_sz );
cerr << "insert:" << page_num << "." << page_oft << " " << u3 << "\n";
*/
return 0;
}
/***********************************************************/
// updateString().
/***********************************************************/
int
page_storage::updateString(mmdb_pos_t loc, const char* base, int len,
int string_ofst, Boolean flush_opt)
{
/*
int u1 = PAGE_ID( loc, page_sz );
int u2 = PAGE_IDX( loc, page_sz );
cerr << "update:" << u1 << "." << u2 << " " << len << " " << string_ofst << "\n";
*/
/*
MESSAGE(cerr, "update string");
debug(cerr, name);
debug(cerr, loc);
*/
int page_num =0;
int slot_num =0;
int offset = 0;
page* y = 0;
spointer_t *x = 0;
while ( len > 0 && loc != 0 ) {
page_num = PAGE_ID( loc, page_sz );
slot_num = PAGE_IDX( loc, page_sz );
//debug(cerr, page_num);
//debug(cerr, slot_num);
y = (*this)(page_num, WRITE);
x = y -> get_spointer(slot_num);
/*
debug(cerr, x -> forward_ptr());
debug(cerr, x -> string_leng());
debug(cerr, x -> string_ofst());
*/
loc = x -> forward_ptr();
int this_len = x -> string_leng();
delete x;
if ( string_ofst >= this_len ) {
string_ofst -= this_len;
continue;
}
int update_len = MIN(len, this_len - string_ofst);
buffer sbuf(0);
sbuf.set_chunk((char*)(base+offset), update_len);
sbuf.set_content_sz(update_len);
y -> update_slot(slot_num, sbuf, string_ofst);
if ( flush_opt == true ) sync(page_num);
string_ofst = 0;
offset += update_len;
len -= update_len;
}
if ( len > 0 ) {
//debug(cerr, len);
//debug(cerr, offset);
/*****************************/
// the update is an expanding
/*****************************/
mmdb_pos_t new_loc;
insertString(new_loc, base+offset, len, flush_opt) ;
y = (*this)(page_num, WRITE);
x = y -> get_spointer(slot_num);
x -> set_forward_ptr(new_loc);
delete x;
page_num = PAGE_ID( new_loc, page_sz );
slot_num = PAGE_IDX( new_loc, page_sz );
y = (*this)(page_num, WRITE);
x = y -> get_spointer(slot_num);
x -> set_mode(spointer_t::FIRST_RECD, false);
delete x;
y -> dirty = true;
return 0;
}
// if ( loc != 0 ) {
/*****************************/
// the update is a shrinking
/*****************************/
// y = (*this)(page_num);
// x = y -> get_spointer(slot_num);
// x -> set_forward_ptr(0);
// return deleteString(loc);
// }
return 0;
}
/***********************************************************/
// deleteString().
/***********************************************************/
int page_storage::deleteString(mmdb_pos_t loc, Boolean flush_opt)
{
while ( loc != 0 ) {
int page_num = PAGE_ID( loc, page_sz );
int slot_num = PAGE_IDX( loc, page_sz );
//debug(cerr, page_num);
//debug(cerr, slot_num);
page* y = (*this)(page_num, WRITE);
spointer_t *x = y -> get_spointer(slot_num);
if ( x -> get_mode(spointer_t::DELETED) == true ) {
delete x;
return 0;
}
loc = x -> forward_ptr();
//debug(cerr, loc);
delete x;
y -> del_slot(slot_num);
if ( flush_opt == true ) sync(page_num);
}
return 0;
}
/***********************************************************/
// allocate a chunk on a page.
/***********************************************************/
int
page_storage::allocString(mmdb_pos_t& loc, int len, char*& string_ptr, int mode)
{
//MESSAGE(cerr, "AllocString:");
//debug(cerr, my_name());
//debug(cerr, len);
if ( len > page_sz ) {
MESSAGE(cerr, "allocString(): string too long");
throw(boundaryException(0, page_sz, len));
}
Boolean new_page;
fbytes_t* v = f_local_pcache.find_host_page(this, new_page, len) ;
page* x = (*this)(v -> page_num, WRITE);
int slot_num;
x->alloc_slot(slot_num, len, string_ptr);
spointer_t* slot_info = x -> get_spointer(slot_num);
slot_info -> add_mode(mode);
delete slot_info;
v -> free_bytes = x -> free_bytes();
f_local_pcache.adjust_heap(v, new_page);
loc = FORM_PAGE_REF(v -> page_num, slot_num, page_sz);
#ifdef STORAGE_DEBUG
MESSAGE(cerr, "in allocString(): final params");
debug(cerr, int(x -> dirty));
debug(cerr, page_num);
debug(cerr, slot_num);
debug(cerr, my_name());
debug(cerr, loc);
debug(cerr, int(string_ptr));
#endif
// int u1 = PAGE_ID( loc, page_sz );
// int u2 = PAGE_IDX( loc, page_sz );
// cerr << "Allocated ID=" << u1 << "." << u2 << " " << len << "\n";
return 0;
}
int page_storage::appendString(mmdb_pos_t loc, const char* base, int len, Boolean)
{
/*
int u1 = PAGE_ID( loc, page_sz );
int u2 = PAGE_IDX( loc, page_sz );
cerr << "append:" << u1 << "." << u2 << " " << len << "\n";
*/
int page_num = 0;
int slot_num = 0;
page* y;
spointer_t *x;
while ( loc != 0 ) {
page_num = PAGE_ID( loc, page_sz );
slot_num = PAGE_IDX( loc, page_sz );
y = (*this)(page_num, READ);
x = y -> get_spointer(slot_num);
loc = x -> forward_ptr();
delete x;
}
insertString(loc, base, len) ;
y = (*this)(page_num, WRITE);
x = y -> get_spointer(slot_num);
x -> set_forward_ptr(loc);
delete x;
page_num = PAGE_ID( loc, page_sz );
slot_num = PAGE_IDX( loc, page_sz );
y = (*this)(page_num, WRITE);
x = y -> get_spointer(slot_num);
x -> set_mode(spointer_t::FIRST_RECD, false);
delete x;
return 0;
}
/***********************************************************/
// create new page frame.
/***********************************************************/
int page_storage::add_page_frames(int pages)
{
total_pages += pages;
//////////////////////////////////////
// prepare the new page in the cache
//////////////////////////////////////
for (int i=1; i<=pages; i++)
operator()(total_pages+i-pages, WRITE);
return 0;
}
/***********************************************************/
// return the mmdb_pos_t of the first page.
/***********************************************************/
int page_storage::first() const
{
return ( total_pages > 0 ) ? 1 : 0;
}
//////////////////////////////////////////
/* ind should be the page id */
//////////////////////////////////////////
page* page_storage::operator()(int ind, enum access mode)
{
/*
if ( mode == WRITE ) {
MESSAGE(cerr, "opera(): write mode");
debug(cerr, ind);
debug(cerr, name);
}
*/
/*
if ( mode == WRITE ) {
char* s = name + strlen(name) - 11;
debug(cerr, s);
if ( strcmp(s, "index.store") == 0 )
debug(cerr, name);
}
*/
//cerr << "Try to get page " << ind << " from " << my_name() << "\n";
if ( ! INRANGE( ind, 1, pages() ) ) {
debug(cerr, my_path());
debug(cerr, my_name());
MESSAGE(cerr,
form("page_storage:: operator(): mmdb_pos_t %d out of range.", ind)
);
throw(boundaryException(1, pages(), ind));
}
page* p = f_local_pcache.in_cache(this, ind);
if ( p == 0 ) {
//cerr << "swapping in a page " << ind << endl;
p = f_global_pcache.load_new_page( this, ind,
(v_db_order==v_server_order) ? false : true
);
}
/*
debug(cerr, my_name());
debug(cerr, p -> count());
debug(cerr, int(mode));
debug(cerr, int(WRITE));
*/
if ( mode == WRITE ) {
p -> dirty = true;
save_to_log(p);
}
return p;
}
/***********************************************************/
// update ind to the mmdb_pos_t of next page.
/***********************************************************/
void page_storage::next(int& ind) const
{
if ( ind >= pages() )
ind = 0;
else
ind++;
}
io_status page_storage::asciiOut(ostream& out)
{
int ind = first();
while ( ind != 0 ) {
#ifdef DEBUG
page* p = (*this)(ind, READ);
debug(out, *p);
#endif
next(ind);
}
return done;
/*
debug(cerr, pagings);
pagings = 0;
*/
}
Boolean
page_storage::seek_loc(mmdb_pos_t& loc, const direction d, int smd)
{
if ( d == positive ) {
return seek_loc_positive(loc, smd);
} else {
return seek_loc_negative(loc, smd);
}
}
Boolean page_storage::seek_loc_positive(mmdb_pos_t& loc, int smd)
{
int pgs = pages();
int page_num = PAGE_ID( loc, page_sz );
int page_slot = PAGE_IDX( loc, page_sz );
while ( page_num <= pgs ) {
page* x = (*this)(page_num, READ);
if ( page_slot == 0 )
page_slot = x -> first();
else
x -> next( page_slot );
spointer_t *y;
while ( page_slot && (y = x -> get_spointer(page_slot)) != 0 ) {
if ( y -> get_mode(spointer_t::DELETED) == false &&
y -> test_mode(smd) == true ) {
loc = FORM_PAGE_REF(page_num, page_slot, page_sz);
delete y;
return true;
} else {
delete y;
x -> next(page_slot);
}
}
page_num++;
page_slot = 0;
}
return false;
}
Boolean page_storage::seek_loc_negative(mmdb_pos_t& loc, int smd)
{
int page_num = PAGE_ID( loc, page_sz );
int page_slot = PAGE_IDX( loc, page_sz );
while ( page_num > 0 ) {
page* x = (*this)(page_num, READ);
if ( page_slot == 0 )
page_slot = x -> count() - 1;
else
x -> prev(page_slot);
spointer_t *y;
while ( page_slot && (y = x -> get_spointer(page_slot)) != 0 )
{
if ( y -> get_mode(spointer_t::DELETED) == false &&
y -> test_mode(smd) == true ) {
loc = FORM_PAGE_REF(page_num, page_slot, page_sz);
delete y;
return true;
} else {
delete y;
x -> prev(page_slot);
}
}
page_num--;
page_slot = 0;
}
return false;
}
void page_storage::reset_paging_count()
{
/*
if ( storage_ptr -> rdbuf() -> is_open() ) {
cerr << storage_ptr -> my_name() << " has not been closed\n";
storage_ptr -> close();
} else {
cerr << storage_ptr -> my_name() << " is already closed\n";
}
*/
pagings = 0;
}
int page_storage::paging_count() const
{
return pagings;
}
mmdb_pos_t page_storage::first_loc()
{
if ( pages() >= 1 && (*this)(1, READ) -> count() != 0 )
return FORM_PAGE_REF(1, 1, page_sz);
else
return 0;
}
mmdb_pos_t page_storage::last_loc()
{
int pgs = pages();
if ( pgs == 0 )
return 0;
for ( int i=pgs; i>0; i-- ) {
int ct = (*this)(i, READ) -> count();
if ( ct > 0 )
return FORM_PAGE_REF(i, ct, page_sz);
}
return 0;
}
int
page_storage::get_str_locs(mmdb_pos_t str_loc,
str_index_record_tPtr*& vector, int& vector_len
)
{
int vector_sz = 20;
vector = new str_index_record_tPtr[vector_sz];
int num_pieces = 0;
int str_offset = 0;
spointer_t *x = 0;
while ( str_loc > 0 ) {
if ( num_pieces >= vector_sz ) {
vector_sz *= 2;
vector = (str_index_record_tPtr*)realloc(
(char*)vector,
vector_sz*sizeof(str_index_record_tPtr)
);
}
vector[num_pieces++] =
new str_index_record_t(str_offset, str_loc);
int page_num = PAGE_ID( str_loc, page_sz );
int page_slot = PAGE_IDX( str_loc, page_sz );
page *y = (*this)(page_num, READ);
x = y -> get_spointer(page_slot);
str_offset += x -> string_leng();
str_loc = x -> forward_ptr();
delete x;
}
vector_len = num_pieces;
return 0;
}
int page_storage::set_page_dirty(mmdb_pos_t loc)
{
MESSAGE(cerr, "set page dirty: page loc is");
debug(cerr, loc);
page* x = (*this)(PAGE_ID( loc, page_sz ), WRITE);
x -> dirty = true;
return 0;
}
Boolean page_storage::io_mode(int mode)
{
if ( storage_ptr )
return storage_ptr -> io_mode(mode);
else
return false;
}
void page_storage::begin_trans()
{
mtry {
if ( trans_info.status == store_trans::ENABLED )
throw(stringException("trans is still in progress"));
trans_info.init(policy);
trans_info.set_max_pages(total_pages);
trans_info.status = store_trans::ENABLED;
int l_max_pages = trans_info.max_pages;
if ( swap_order() == true )
ORDER_SWAP_UINT(l_max_pages);
trans_info.log_store ->
updateString(0, (char*)&l_max_pages, sizeof(l_max_pages), 0, true);
}
mcatch (mmdbException&, e) {
// workaround for solaris's /SUNWspro/bin/CC compiler.
beginTransException x;
throw(x);
//throw(beginTransException());
}
end_try;
}
void page_storage::commit_trans()
{
//////////////////////////////
// sync the touched pages
//////////////////////////////
mtry {
int ind = trans_info.log_index -> first_bucket();
while ( ind != -1 ) {
imp_bucket* bucket = trans_info.log_index -> get_bucket(ind);
if ( bucket ) {
long b_ind = bucket -> first();
while ( b_ind != 0 ) {
data_t* z = (*bucket)(b_ind);
//debug(cerr, ((page*)(z -> dt)) -> count());
sync((page*)(z -> dt));
bucket -> next(b_ind);
}
}
trans_info.log_index -> next_bucket(ind);
}
trans_info.quit();
trans_info.status = store_trans::DISABLED;
}
mcatch (mmdbException &,e) {
// workaround for solaris's /SUNWspro/bin/CC compiler.
commitTransException x;
throw(x);
} end_try;
}
void page_storage::roll_back()
{
mtry
{
if ( exist_file(form("%s.log", name), path) == false )
return;
MESSAGE(cerr, "roll_back() begins");
trans_info.init(policy); // init the log store
//////////////////////////////////
// verify the log is in good shape
//////////////////////////////////
int m;
unsigned int log_bytes = trans_info.log_store -> bytes();
if ( trans_info.log_store &&
(*trans_info.log_store) &&
log_bytes > sizeof(m) )
{
//////////////////////////////////
// truncate the store to previous
// length
//////////////////////////////////
trans_info.log_store -> readString(0, (char*)&m, sizeof(m));
if ( swap_order() == true )
ORDER_SWAP_UINT(m);
trans_info.set_max_pages(m); // init the log store
((unixf_storage*)storage_ptr) -> truncate(abs_off + m*page_sz);
//debug(cerr, m);
//////////////////////////////////
// restore the store to previous
// state
//////////////////////////////////
int l_pid = 0;
if ( (log_bytes - sizeof(m)) % (page_sz+sizeof(l_pid)) != 0 )
throw(stringException("corrupted transaction log"));
int u = (log_bytes - sizeof(m)) / (page_sz+sizeof(l_pid));
//debug(cerr, u);
buffer log_buf(page_sz);
for ( int i=0; i<u; i++ ) {
int offset = sizeof(m) + i*(page_sz + sizeof(l_pid));
trans_info.log_store ->
readString(offset, // page id
(char*)&l_pid, sizeof(l_pid)
);
if ( swap_order() == true ) // swap byte order if necessary
ORDER_SWAP_UINT(l_pid);
trans_info.log_store ->
readString(offset + sizeof(l_pid), // page content
log_buf.get_base(),
page_sz
);
storage_ptr -> updateString( abs_off + (l_pid-1)*page_sz,
log_buf.get_base(),
page_sz,
0,
true
);
}
}
///////////////////////////////////////////////
// make sure the cached pages are not synced
///////////////////////////////////////////////
long ind = f_global_pcache.f_replace_policy.first();
while ( ind != 0 ) {
lru_page *p = (lru_page*)
(f_global_pcache.f_replace_policy)(ind, ACTIVE);
if ( p -> f_store == this )
p -> dirty = false;
f_global_pcache.f_replace_policy.next(ind);
}
trans_info.quit(); // remove the log store
trans_info.status = store_trans::DISABLED;
}
mcatch (mmdbException &,e)
{
// workaround for solaris's /SUNWspro/bin/CC compiler.
rollbackTransException x;
throw(x);
} end_try;
MESSAGE(cerr, "roll_back() completes");
}
void page_storage::save_to_log(page* p)
{
/*
MESSAGE(cerr, "About to save to log");
debug(cerr, my_name());
debug(cerr, int(trans_info.status));
debug(cerr, int(store_trans::ENABLED));
debug(cerr, trans_info.max_pages);
*/
if ( trans_info.status == store_trans::ENABLED &&
INRANGE(p -> page_id(), 1, trans_info.max_pages)
)
{
//assert ( trans_info.log_store );
//assert ( trans_info.log_index );
if ( trans_info.log_store == 0 || trans_info.log_index == 0 )
throw(stringException("corrupted store"));
int l_pid = p -> page_id();
data_t pkey(l_pid, voidPtr(p));
if ( trans_info.log_index -> member(pkey) == false ) {
//MESSAGE(cerr, form("Save_to_log pid=%d, pcnt = %d, name=%s",
// l_pid, p -> count(), name));
int log_bytes_before = trans_info.log_store -> bytes();
mtry {
if ( swap_order() == true ) // swap to desired order
ORDER_SWAP_UINT(l_pid);
trans_info.log_store ->
appendString( 0, (char*)&l_pid, sizeof(l_pid), false );
if ( swap_order() == true ) // swap back
ORDER_SWAP_UINT(l_pid);
p -> _swap_order(false);
trans_info.log_store ->
appendString( 0, p -> page_base(), page_sz, true );
//debug(cerr, trans_info.log_store -> bytes());
p -> _swap_order(true);
trans_info.log_index -> insert(pkey);
}
mcatch (mmdbException&, e) {
trans_info.log_store -> truncate(log_bytes_before);
rethrow;
}
end_try;
}
// else
//MESSAGE(cerr, form("Not save_to_log pid=%d, name=%s", l_pid, name));
}
}
buffer& page_storage::aux_buf()
{
if ( v_buf == 0 )
v_buf = new buffer(LBUFSIZ);
return *v_buf;
}