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firebird-mirror/src/jrd/sort.cpp

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/*
* PROGRAM: JRD Sort
* MODULE: sort.cpp
* DESCRIPTION: Top level sort module
*
* The contents of this file are subject to the Interbase Public
* License Version 1.0 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy
* of the License at http://www.Inprise.com/IPL.html
*
* Software distributed under the License is distributed on an
* "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express
* or implied. See the License for the specific language governing
* rights and limitations under the License.
*
* The Original Code was created by Inprise Corporation
* and its predecessors. Portions created by Inprise Corporation are
* Copyright (C) Inprise Corporation.
*
* All Rights Reserved.
* Contributor(s): ______________________________________.
* $Id: sort.cpp,v 1.68 2004-05-17 22:27:56 brodsom Exp $
*
* 2001-09-24 SJL - Temporary fix for large sort file bug
*
* 2002.10.29 Sean Leyne - Removed obsolete "Netware" port
*
* 2002.10.30 Sean Leyne - Removed support for obsolete "PC_PLATFORM" define
*
*/
#include "firebird.h"
#include <errno.h>
#include <string.h>
#include "../jrd/common.h"
#include "../jrd/jrd.h"
#include "../jrd/sort.h"
#include "../jrd/sort_mem.h"
#include "gen/iberror.h"
#include "../jrd/intl.h"
#include "../jrd/gdsassert.h"
#include "../jrd/rse.h"
#include "../jrd/val.h"
#include "../jrd/err_proto.h"
#include "../jrd/dls_proto.h"
#include "../jrd/gds_proto.h"
#include "../jrd/sort_proto.h"
#include "../jrd/all_proto.h"
#include "../jrd/sch_proto.h"
#include "../jrd/thread_proto.h"
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_UIO_H
#include <sys/uio.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_STDIO_H
#include <stdio.h>
#endif
#ifdef WIN_NT
/* for SEEK_SET */
#include <io.h> // lseek, read, write, close
#endif
const ULONG IO_RETRY = 20;
const USHORT RUN_GROUP = 8;
const USHORT MAX_MERGE_LEVEL = 2;
#ifdef VMS
double MTH$CVT_D_G(), MTH$CVT_G_D();
#endif
using namespace Jrd;
// The sort buffer size should be just under a multiple of the
// hardware memory page size to account for memory allocator
// overhead. On most platorms, this saves 4KB to 8KB per sort
// buffer from being allocated but not used.
const ULONG SORT_BUFFER_CHUNK_SIZE = 4096;
const ULONG MIN_SORT_BUFFER_SIZE = SORT_BUFFER_CHUNK_SIZE * 4;
const ULONG MAX_SORT_BUFFER_SIZE = SORT_BUFFER_CHUNK_SIZE * 32;
const ULONG MAX_TEMPFILE_SIZE = 1073741824; // 1GB
#define DIFF_LONGS(a,b) ((a) - (b))
#define SWAP_LONGS(a,b,t) {t=a; a=b; b=t;}
// Compare p and q both SORTP pointers for l 32-bit longwords
// l != 0 if p and q are not equal for l bytes
#define DO_32_COMPARE(p, q, l) do if (*p++ != *q++) break; while (--l);
#define MOVE_32(len,from,to) memcpy(to, from, len*4)
// These values are not defined as const as they are passed to
// the diddle_key routines which mangles them.
// As the diddle_key routines differ on VAX (little endian) and non VAX
// (big endian) patforms, making the following const caused a core on the
// Intel Platforms, while Solaris was working fine.
static ULONG low_key[] = { 0, 0, 0, 0, 0, 0 };
static ULONG high_key[] = {
ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX,
ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX,
ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX,
ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX,
ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX,
ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX,
ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX,
ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX, ULONG_MAX};
#ifdef SCROLLABLE_CURSORS
static sort_record* get_merge(merge_control*, sort_context*, RSE_GET_MODE);
#else
static void diddle_key(UCHAR *, sort_context*, bool);
static sort_record* get_merge(merge_control*, sort_context*);
#endif
static UCHAR* sort_alloc(sort_context*, ULONG);
static void error_memory(sort_context*);
static ULONG find_file_space(sort_context*, ULONG, sort_work_file**);
static void free_file_space(sort_context*, sort_work_file*, ULONG, ULONG);
static void init(sort_context*);
static bool local_fini(sort_context*, Attachment*);
static void merge_runs(sort_context*, USHORT);
static void quick(SLONG, SORTP **, ULONG);
static ULONG order(sort_context*);
static void put_run(sort_context*);
static void sort(sort_context*);
#ifdef NOT_USED_OR_REPLACED
#ifdef DEBUG
static void validate(sort_context*);
#endif
#endif
#ifdef DEBUG_SORT_TRACE
static void write_trace(UCHAR*, sort_work_file*, ULONG, BLOB_PTR*, ULONG);
#include <stdio.h>
FILE *trace_file = NULL;
#endif
#ifdef SMALL_FILE_NAMES
static const char* SCRATCH = "fb_s";
#else
static const char* SCRATCH = "fb_sort_";
#endif
#ifdef SCROLLABLE_CURSORS
#ifdef WORDS_BIGENDIAN
void SORT_diddle_key(UCHAR* record, sort_context* scb, bool direction)
{
/**************************************
*
* S O R T _ d i d d l e _ k e y ( n o n - V A X )
*
**************************************
*
* Functional description
* Perform transformation between the natural form of a record
* and a form that can be sorted in unsigned comparison order.
*
* direction - true for SORT_put() and false for SORT_get()
*
**************************************/
const sort_key_def* key = scb->scb_description;
for (const sort_key_def* const end = key + scb->scb_keys; key < end; key++)
{
UCHAR* p = record + key->skd_offset;
USHORT n = key->skd_length;
bool complement = key->skd_flags & SKD_descending;
switch (key->skd_dtype) {
case SKD_ulong:
case SKD_ushort:
case SKD_bytes:
break;
// Stash embedded control info for non-fixed data types in the sort
// record and zap it so that it doesn't interfere with collation
case SKD_varying:
if (direction) {
if (!(scb->scb_flags & scb_sorted)) {
*((USHORT *) (record + key->skd_vary_offset)) =
((vary*) p)->vary_length;
const UCHAR fill_char =
(key->skd_flags & SKD_binary) ? 0 : ASCII_SPACE;
UCHAR* fill_pos = p + sizeof(USHORT) + ((vary*) p)->vary_length;
const USHORT fill = n - sizeof(USHORT) - ((vary*) p)->vary_length;
if (fill)
memset(fill_pos, fill_char, fill);
}
((vary*) p)->vary_length = 0;
}
break;
case SKD_cstring:
if (direction) {
const UCHAR fill_char = (key->skd_flags & SKD_binary) ? 0 : ASCII_SPACE;
if (!(scb->scb_flags & scb_sorted)) {
const USHORT l = strlen(p);
*((USHORT *) (record + key->skd_vary_offset)) = l;
UCHAR* fill_pos = p + l;
const USHORT fill = n - l;
if (fill)
memset(fill_pos, fill_char, fill);
}
else {
const USHORT l = *((USHORT *) (record + key->skd_vary_offset));
*(p + l) = fill_char;
}
}
break;
case SKD_text:
break;
case SKD_float:
case SKD_double:
{
const USHORT flag = (direction || !complement) ? (direction ? TRUE : FALSE) : TRUE;
if (flag ^ (*p >> 7))
*p ^= 1 << 7;
else
complement = !complement;
break;
}
case SKD_long:
case SKD_short:
case SKD_quad:
case SKD_timestamp1:
case SKD_timestamp2:
case SKD_sql_time:
case SKD_sql_date:
case SKD_int64:
*p ^= 1 << 7;
break;
default:
fb_assert(false);
break;
}
if (complement && n)
do {
*p++ ^= -1;
} while (--n);
// Flatter but don't complement control info for non-fixed
// data types when restoring the data
if (key->skd_dtype == SKD_varying && !direction) {
p = record + key->skd_offset;
((vary*) p)->vary_length = *((USHORT *) (record + key->skd_vary_offset));
}
if (key->skd_dtype == SKD_cstring && !direction) {
p = record + key->skd_offset;
const USHORT l = *((USHORT *) (record + key->skd_vary_offset));
*(p + l) = 0;
}
}
}
#else
void SORT_diddle_key(UCHAR* record, sort_context* scb, bool direction)
{
/**************************************
*
* S O R T _ d i d d l e _ k e y ( V A X )
*
**************************************
*
* Functional description
* Perform transformation between the natural form of a record
* and a form that can be sorted in unsigned comparison order.
*
* direction - true for SORT_put() and false for SORT_get()
*
**************************************/
UCHAR c1, c2, fill_char, *fill_pos;
USHORT w, l, fill;
SSHORT longs, flag;
ULONG lw;
#ifdef VMS
double *dp;
#endif
const sort_key_def* key = scb->scb_description;
for (const sort_key_def* const end = key + scb->scb_keys; key < end; key++)
{
BLOB_PTR* p = (BLOB_PTR *) record + key->skd_offset;
USHORT* wp = (USHORT *) p;
SORTP* lwp = (SORTP *) p;
bool complement = key->skd_flags & SKD_descending;
USHORT n = ROUNDUP(key->skd_length, sizeof(SLONG));
switch (key->skd_dtype) {
case SKD_timestamp1:
case SKD_timestamp2:
case SKD_sql_date:
case SKD_sql_time:
p[3] ^= 1 << 7;
break;
case SKD_ulong:
case SKD_ushort:
break;
case SKD_text:
case SKD_bytes:
case SKD_cstring:
case SKD_varying:
// Stash embedded control info for non-fixed data types in the sort
// record and zap it so that it doesn't interfere with collation
if (key->skd_dtype == SKD_varying && direction) {
if (!(scb->scb_flags & scb_sorted)) {
*((USHORT *) (record + key->skd_vary_offset)) = l =
((vary*) p)->vary_length;
fill_char =
(key->skd_flags & SKD_binary) ? 0 : ASCII_SPACE;
fill_pos = p + sizeof(USHORT) + l;
fill = n - sizeof(USHORT) - l;
if (fill)
memset(fill_pos, fill_char, fill);
}
((vary*) p)->vary_length = 0;
}
if (key->skd_dtype == SKD_cstring && direction) {
fill_char = (key->skd_flags & SKD_binary) ? 0 : ASCII_SPACE;
if (!(scb->scb_flags & scb_sorted)) {
*((USHORT *) (record + key->skd_vary_offset)) = l =
strlen(p);
fill_pos = p + l;
fill = n - l;
if (fill)
memset(fill_pos, fill_char, fill);
}
else {
l = *((USHORT *) (record + key->skd_vary_offset));
*(p + l) = fill_char;
}
}
longs = n >> SHIFTLONG;
while (--longs >= 0) {
c1 = p[3];
p[3] = *p;
*p++ = c1;
c1 = p[1];
p[1] = *p;
*p = c1;
p += 3;
}
p = (BLOB_PTR*) wp;
break;
case SKD_short:
p[1] ^= 1 << 7;
break;
case SKD_long:
p[3] ^= 1 << 7;
break;
case SKD_quad:
p[7] ^= 1 << 7;
break;
case SKD_int64:
// INT64's fit in TWO LONGS, and hence the SWAP has to happen
// here for the right order comparison using DO_32_COMPARE
if (!direction)
SWAP_LONGS(lwp[0], lwp[1], lw);
p[7] ^= 1 << 7;
if (direction)
SWAP_LONGS(lwp[0], lwp[1], lw);
break;
#ifdef IEEE
case SKD_double:
if (!direction) {
lw = lwp[0];
lwp[0] = lwp[1];
lwp[1] = lw;
}
flag = (direction || !complement) ? direction : TRUE;
if (flag ^ (p[7] >> 7))
p[7] ^= 1 << 7;
else
complement = !complement;
if (direction) {
lw = lwp[0];
lwp[0] = lwp[1];
lwp[1] = lw;
}
break;
case SKD_float:
flag = (direction || !complement) ? direction : TRUE;
if (flag ^ (p[3] >> 7))
p[3] ^= 1 << 7;
else
complement = !complement;
break;
#else // IEEE
#ifdef VMS
case SKD_d_float:
dp = (double *) p;
if (direction)
*dp = MTH$CVT_D_G(dp);
#endif
case SKD_double:
w = wp[2];
wp[2] = wp[3];
wp[3] = w;
#ifndef VMS
case SKD_d_float:
#endif
case SKD_float:
if (!direction)
if (complement) {
if (p[3] & 1 << 7)
complement = !complement;
else
p[3] ^= 1 << 7;
}
else {
if (p[3] & 1 << 7)
p[3] ^= 1 << 7;
else
complement = !complement;
}
w = wp[0];
wp[0] = wp[1];
wp[1] = w;
if (direction)
if (p[3] & 1 << 7)
complement = !complement;
else
p[3] ^= 1 << 7;
#ifdef VMS
else if (key->skd_dtype == SKD_d_float)
*dp = MTH$CVT_G_D(dp);
#endif
break;
#endif // IEEE
default:
fb_assert(false);
break;
}
if (complement && n)
do
*p++ ^= -1;
while (--n);
// Flatter but don't complement control info for non-fixed
// data types when restoring the data
if (key->skd_dtype == SKD_varying && !direction) {
p = (BLOB_PTR *) record + key->skd_offset;
((vary*) p)->vary_length = *((USHORT *) (record + key->skd_vary_offset));
}
if (key->skd_dtype == SKD_cstring && !direction) {
p = (BLOB_PTR *) record + key->skd_offset;
l = *((USHORT *) (record + key->skd_vary_offset));
*(p + l) = 0;
}
}
}
#endif
#endif
void SORT_error(ISC_STATUS* status_vector,
sort_work_file* sfb, TEXT* string, ISC_STATUS operation, int errcode)
{
/**************************************
*
* S O R T _ e r r o r
*
**************************************
*
* Functional description
* Report fatal error.
*
**************************************/
fb_assert(status_vector != NULL);
*status_vector++ = isc_arg_gds;
*status_vector++ = isc_io_error;
*status_vector++ = isc_arg_string;
// CVC: Warning, converting pointer to ISC_STATUS => SLONG in 32 bits.
*status_vector++ = (ISC_STATUS) string;
*status_vector++ = isc_arg_string;
*status_vector++ = (ISC_STATUS) (U_IPTR) ERR_cstring(sfb->sfb_file_name);
*status_vector++ = isc_arg_gds;
*status_vector++ = operation;
if (errcode) {
*status_vector++ = SYS_ERR;
*status_vector++ = errcode;
}
*status_vector++ = isc_arg_gds;
*status_vector++ = isc_sort_err; // Msg355: sort error
*status_vector = isc_arg_end;
ERR_punt();
}
void SORT_fini(sort_context* scb, Attachment* att)
{
/**************************************
*
* S O R T _ f i n i
*
**************************************
*
* Functional description
* Finish sort, and release all resources.
*
**************************************/
if (scb && local_fini(scb, att))
gds__free(scb);
}
#ifdef SCROLLABLE_CURSORS
void SORT_get(ISC_STATUS * status_vector,
sort_context* scb, ULONG ** record_address, RSE_GET_MODE mode)
{
/**************************************
*
* S O R T _ g e t ( I B _ V 4 _ 1 )
*
**************************************
*
* Functional description
* Get a record from sort (in order, of course).
* The address of the record is returned in <record_address>
* If the stream is exhausted, SORT_get puts NULL in <record_address>.
*
**************************************/
sort_record* record;
scb->scb_status_vector = status_vector;
// If there were runs, get the records from the merge
// tree. Otherwise everything fit in memory.
if (scb->scb_merge)
record = get_merge(scb->scb_merge, scb, mode);
else
switch (mode) {
case RSE_get_forward:
if (scb->scb_flags & scb_initialized)
scb->scb_flags &= ~scb_initialized;
while (true) {
if (scb->scb_next_pointer > scb->scb_last_pointer) {
record = NULL;
break;
}
if (record = *scb->scb_next_pointer++)
break;
}
break;
case RSE_get_backward:
if (scb->scb_flags & scb_initialized) {
scb->scb_flags &= ~scb_initialized;
scb->scb_next_pointer = scb->scb_last_pointer + 1;
}
else {
// By definition, the next pointer is on the next record,
// so we have to go back one to get to the last fetched record.
// This is easier than changing the sense of the next pointer.
scb->scb_next_pointer--;
if (scb->scb_next_pointer <= scb->scb_first_pointer + 1) {
record = NULL;
scb->scb_next_pointer++;
break;
}
}
while (true) {
scb->scb_next_pointer--;
if (scb->scb_next_pointer <= scb->scb_first_pointer) {
record = NULL;
scb->scb_next_pointer++;
break;
}
if (record = *scb->scb_next_pointer)
break;
}
// Reset next pointer to one greater than the last fetched
scb->scb_next_pointer++;
break;
#ifdef PC_ENGINE
case RSE_get_current:
if (scb->scb_next_pointer <= scb->scb_first_pointer ||
scb->scb_next_pointer > scb->scb_last_pointer)
{
record = NULL;
}
record = *scb->scb_next_pointer;
break;
#endif
default:
fb_assert(FALSE);
break;
}
if (record)
SORT_diddle_key((UCHAR *) record->sort_record_key, scb, false);
*record_address = (ULONG *) record;
}
#else
void SORT_get(ISC_STATUS* status_vector, sort_context* scb, ULONG** record_address)
{
/**************************************
*
* S O R T _ g e t
*
**************************************
*
* Functional description
* Get a record from sort (in order, of course).
* The address of the record is returned in <record_address>
* If the stream is exhausted, SORT_get puts NULL in <record_address>.
*
**************************************/
sort_record* record;
scb->scb_status_vector = status_vector;
// If there weren't any runs, everything fit in memory. Just return stuff.
if (!scb->scb_merge)
while (true) {
if (scb->scb_records == 0) {
record = NULL;
break;
}
scb->scb_records--;
if ( (record = *scb->scb_next_pointer++) )
break;
}
else
record = get_merge(scb->scb_merge, scb);
*record_address = (ULONG *) record;
if (record) {
diddle_key((UCHAR *) record->sort_record_key, scb, false);
}
}
#endif
sort_context* SORT_init(ISC_STATUS* status_vector,
USHORT record_length,
USHORT keys,
const sort_key_def* key_description,
FPTR_REJECT_DUP_CALLBACK call_back,
void* user_arg,
Attachment* att,
UINT64 max_records)
{
/**************************************
*
* S O R T _ i n i t
*
**************************************
*
* Functional description
* Initialize for a sort. All we really need is a description
* of the sort keys. Return the address of a sort context block.
* If duplicate control is required, the user may specify a call
* back routine. If supplied, the call back routine is called
* with three argument: the two records and the user supplied
* argument. If the call back routine returns TRUE, the second
* duplicate record is eliminated.
*
**************************************/
// Allocate and setup a sort context block, including copying the
// key description vector. Round the record length up to the next
// longword, and add a longword to a pointer back to the pointer slot.
sort_context* scb = (sort_context*) gds__alloc((SLONG) SCB_LEN(keys));
if (!scb) {
// FREE: scb is freed by SORT_fini(), called by higher level cleanup
// FREE: or later in this module in error cases
*status_vector++ = isc_arg_gds;
*status_vector++ = isc_sort_mem_err;
*status_vector = isc_arg_end;
return NULL;
}
memset((UCHAR*) scb, 0, SCB_LEN(keys));
scb->scb_status_vector = status_vector;
scb->scb_length = record_length;
scb->scb_longs =
ROUNDUP(record_length + sizeof(SLONG*), sizeof(SLONG*)) >> SHIFTLONG;
scb->scb_dup_callback = call_back;
scb->scb_dup_callback_arg = user_arg;
scb->scb_keys = keys;
scb->scb_max_records = max_records;
sort_key_def* p = scb->scb_description;
const sort_key_def* q = key_description;
do {
*p++ = *q++;
} while (--keys);
--p;
scb->scb_key_length =
ROUNDUP(p->skd_offset + p->skd_length, sizeof(SLONG)) >> SHIFTLONG;
// Next, try to allocate a "big block". How big? Big enough!
#ifdef DEBUG_MERGE
// To debug the merge algorithm, force the in-memory pool to be VERY small
scb->scb_size_memory = 2000;
scb->scb_memory =
(SORTP *) gds__alloc((SLONG) scb->scb_size_memory);
// FREE: scb_memory is freed by local_fini()
#else
// Try to get a big chunk of memory, if we can't try smaller and
// smaller chunks until we can get the memory. If we get down to
// too small a chunk - punt and report not enough memory.
for (scb->scb_size_memory = MAX_SORT_BUFFER_SIZE;;
scb->scb_size_memory -= SORT_BUFFER_CHUNK_SIZE)
{
if (scb->scb_size_memory < MIN_SORT_BUFFER_SIZE)
break;
else if ( (scb->scb_memory =
(SORTP *) gds__alloc((SLONG) scb->scb_size_memory)) )
{
// FREE: scb_memory is freed by local_fini()
break;
}
}
#endif // DEBUG_MERGE
if (!scb->scb_memory) {
*status_vector++ = isc_arg_gds;
*status_vector++ = isc_sort_mem_err; // Msg356: sort error: not enough memory
*status_vector = isc_arg_end;
gds__free(scb);
return NULL;
}
scb->scb_end_memory =
(SORTP *) ((BLOB_PTR *) scb->scb_memory + scb->scb_size_memory);
scb->scb_first_pointer = (sort_record**) scb->scb_memory;
// Set up to receive the first record
init(scb);
// If a linked list pointer was given, link in new sort block
if (att) {
scb->scb_next = att->att_active_sorts;
att->att_active_sorts = scb;
scb->scb_attachment = att;
}
return scb;
}
void SORT_put(ISC_STATUS * status_vector, sort_context* scb, ULONG ** record_address)
{
/**************************************
*
* S O R T _ p u t
*
**************************************
*
* Functional description
* Allocate space for a record for sort. The caller is responsible
* for moving in the record.
*
* Records are added from the top (higher addresses) of sort memory going down. Record
* pointers are added at the bottom (lower addresses) of sort memory going up. When
* they overlap, the records in memory are sorted and written to a "run"
* in the scratch files. The runs are eventually merged.
*
**************************************/
scb->scb_status_vector = status_vector;
// Find the last record passed in, and zap the keys something comparable
// by unsigned longword compares
SR* record = scb->scb_last_record;
if (record != (SR *) scb->scb_end_memory)
#ifdef SCROLLABLE_CURSORS
SORT_diddle_key((UCHAR *) (record->sr_sort_record.sort_record_key),
scb, true);
#else
diddle_key((UCHAR *) (record->sr_sort_record.sort_record_key), scb,
true);
#endif
// If there isn't room for the record, sort and write the run_control.
// Check that we are not at the beginning of the buffer in addition
// to checking for space for the record. This avoids the pointer
// record from underflowing in the second condition.
if ((BLOB_PTR *) record < (BLOB_PTR *) (scb->scb_memory + scb->scb_longs)
|| (BLOB_PTR *) NEXT_RECORD(record) <= (BLOB_PTR *) (scb->scb_next_pointer + 1))
{
put_run(scb);
while (true) {
run_control* run = scb->scb_runs;
const USHORT depth = run->run_depth;
if (depth == MAX_MERGE_LEVEL)
break;
USHORT count = 1;
while ((run = run->run_next) && run->run_depth == depth)
count++;
if (count < RUN_GROUP)
break;
merge_runs(scb, count);
}
init(scb);
record = scb->scb_last_record;
}
record = NEXT_RECORD(record);
// Make sure the first longword of the record points to the pointer
scb->scb_last_record = record;
record->sr_bckptr = scb->scb_next_pointer;
// Move key_id into *scb->scb_next_pointer and then
// increment scb->scb_next_pointer
*scb->scb_next_pointer++ =
reinterpret_cast<sort_record*>(record->sr_sort_record.sort_record_key);
#ifndef SCROLLABLE_CURSORS
scb->scb_records++;
#endif
*record_address = (ULONG *) record->sr_sort_record.sort_record_key;
}
#ifdef SCROLLABLE_CURSORS
void SORT_read_block(
#else
ULONG SORT_read_block(
#endif
ISC_STATUS* status_vector,
sort_work_file* sfb,
ULONG seek, BLOB_PTR * address, ULONG length)
{
/**************************************
*
* S O R T _ r e a d _ b l o c k
*
**************************************
*
* Functional description
* Read a block of stuff from a scratch file.
*
**************************************/
ULONG read_len, i;
#ifdef DEBUG_SORT_TRACE
UCHAR *org_address;
ULONG org_length, org_seek;
org_address = address;
org_length = length;
org_seek = seek;
#endif
// Checkout of engine on sort I/O
THREAD_EXIT();
// The following is a crock induced by a VMS C bug
while (length) {
const ULONG len = length;
for (i = 0; i < IO_RETRY; i++) {
if (lseek(sfb->sfb_file, LSEEK_OFFSET_CAST seek, SEEK_SET) == -1) {
THREAD_ENTER();
SORT_error(status_vector, sfb, "lseek", isc_io_read_err, errno);
}
if ((read_len = read(sfb->sfb_file, address, len)) == len)
break;
else if ((SSHORT) read_len == -1 && !SYSCALL_INTERRUPTED(errno)) {
THREAD_ENTER();
SORT_error(status_vector, sfb, "read", isc_io_read_err, errno);
}
}
if (i == IO_RETRY) {
THREAD_ENTER();
SORT_error(status_vector, sfb, "read", isc_io_read_err, errno);
}
length -= read_len;
address += read_len;
seek += read_len;
}
THREAD_ENTER();
#ifdef DEBUG_SORT_TRACE
write_trace("Read", sfb, org_seek, org_address, org_length);
#endif
#ifndef SCROLLABLE_CURSORS
return seek;
#endif
}
void SORT_shutdown(Attachment* att)
{
/**************************************
*
* S O R T _ s h u t d o w n
*
**************************************
*
* Functional description
* Clean up any pending sorts.
*
**************************************/
// We ignore the result from local_fini,
// since the expectation is that from the
// way we are passing in the structures
// that every sort_context *IS* part of the ptr
// chain. Also, we're not freeing the
// structure here, so if something goes
// wrong, it's not *CRITICAL*. -- mrs
while (att->att_active_sorts)
local_fini(att->att_active_sorts, att);
}
bool SORT_sort(ISC_STATUS * status_vector, sort_context* scb)
{
/**************************************
*
* S O R T _ s o r t
*
**************************************
*
* Functional description
* Perform any intermediate computing before giving records
* back. If there weren't any runs, run sort the buffer.
* If there were runs, sort and write out the last run_control and
* build a merge tree.
*
**************************************/
run_control* run;
merge_control* merge;
merge_control* merge_pool;
scb->scb_status_vector = status_vector;
if (scb->scb_last_record != (SR *) scb->scb_end_memory)
#ifdef SCROLLABLE_CURSORS
SORT_diddle_key((UCHAR *) KEYOF(scb->scb_last_record), scb, true);
#else
diddle_key((UCHAR *) KEYOF(scb->scb_last_record), scb, true);
#endif
// If there aren't any runs, things fit nicely in memory. Just sort the mess
// and we're ready for output.
if (!scb->scb_runs) {
sort(scb);
#ifdef SCROLLABLE_CURSORS
scb->scb_last_pointer = scb->scb_next_pointer - 1;
#endif
scb->scb_next_pointer = scb->scb_first_pointer + 1;
#ifdef SCROLLABLE_CURSORS
scb->scb_flags |= scb_initialized;
#endif
scb->scb_flags |= scb_sorted;
return true;
}
// Write the last records as a run_control
put_run(scb);
// Build a merge tree for the run_control blocks. Start by laying them all out
// in a vector. This is done to allow us to build a merge tree from the
// bottom up, ensuring that a balanced tree is built.
ULONG run_count;
for (run_count = 0, run = scb->scb_runs; run; run = run->run_next) {
if (run->run_buff_alloc) {
gds__free(run->run_buffer);
run->run_buff_alloc = 0;
}
++run_count;
}
run_merge_hdr* streams_local[200];
run_merge_hdr** streams;
if ((run_count * sizeof(run_merge_hdr*)) > sizeof(streams_local))
streams =
(run_merge_hdr**) gds__alloc((SLONG) run_count * sizeof(run_merge_hdr*));
// FREE: streams is freed later in this routine
else
streams = streams_local;
if (!streams) {
*status_vector++ = isc_arg_gds;
*status_vector++ = isc_sort_mem_err;
*status_vector = isc_arg_end;
return false;
}
run_merge_hdr** m1 = streams;
for (run = scb->scb_runs; run; run = run->run_next)
*m1++ = (run_merge_hdr*) run;
ULONG count = run_count;
// We're building a b-tree of the sort merge blocks, we have (count)
// leaves already, so we *know* we need (count-1) merge blocks.
if (count > 1) {
fb_assert(!scb->scb_merge_pool); // shouldn't have a pool
scb->scb_merge_pool =
(merge_control*) gds__alloc((SLONG) (count - 1) * sizeof(merge_control));
// FREE: smb_merge_pool freed in local_fini() when the scb is released
merge_pool = scb->scb_merge_pool;
if(!merge_pool) {
gds__free(streams);
*status_vector++ = isc_arg_gds;
*status_vector++ = isc_sort_mem_err;
*status_vector = isc_arg_end;
return false;
}
memset(merge_pool, 0, (count - 1) * sizeof(merge_control));
}
else {
// Merge of 1 or 0 runs doesn't make sense
fb_assert(false); // We really shouldn't get here
merge = (merge_control*) * streams; // But if we do...
}
// Each pass through the vector builds a level of the merge tree
// by condensing two runs into one.
// We will continue to make passes until there is a single item.
//
// See also kissing cousin of this loop in merge_runs()
while (count > 1) {
run_merge_hdr** m2 = m1 = streams;
// "m1" is used to sequence through the runs being merged,
// while "m2" points at the new merged run
while (count >= 2) {
merge = merge_pool++;
merge->mrg_header.rmh_type = TYPE_MRG;
fb_assert(((*m1)->rmh_type == TYPE_MRG) || // garbage watch
((*m1)->rmh_type == TYPE_RUN));
(*m1)->rmh_parent = merge;
merge->mrg_stream_a = *m1++;
fb_assert(((*m1)->rmh_type == TYPE_MRG) || // garbage watch
((*m1)->rmh_type == TYPE_RUN));
(*m1)->rmh_parent = merge;
merge->mrg_stream_b = *m1++;
merge->mrg_record_a = NULL;
merge->mrg_record_b = NULL;
*m2++ = (run_merge_hdr*) merge;
count -= 2;
}
if (count)
*m2++ = *m1++;
count = m2 - streams;
}
if (streams != streams_local)
gds__free(streams);
SORTP* buffer = (SORTP *) scb->scb_first_pointer;
merge->mrg_header.rmh_parent = NULL;
scb->scb_merge = merge;
scb->scb_longs -= SIZEOF_SR_BCKPTR_IN_LONGS;
// Divvy up the sort space among buffers for runs. Although something slightly
// better could be arranged, for now give them all the same size hunk.
ULONG size;
const ULONG temp = DIFF_LONGS(scb->scb_end_memory, buffer);
count = temp / (scb->scb_longs * run_count);
if (count) {
size = count * (SSHORT) scb->scb_longs;
count = run_count;
}
else {
size = (SSHORT) scb->scb_longs;
count = temp / scb->scb_longs;
}
// Allocate buffer space for either all the runs, if they fit, or for
// as many as allow
for (run = scb->scb_runs; run && count; count--, run = run->run_next) {
run->run_buffer = buffer;
buffer += size;
run->run_record =
reinterpret_cast<sort_record*>(run->run_end_buffer = buffer);
}
// If there was not enough buffer space, get some more for the remaining runs
// allocating enough for the merge space plus a link
for (; run; run = run->run_next) {
run->run_buffer =
(ULONG *) gds__alloc((SLONG) (size * sizeof(ULONG)));
// FREE: smb_merge_space freed in local_fini() when the scb is released
if (!run->run_buffer) {
*status_vector++ = isc_arg_gds;
*status_vector++ = isc_sort_mem_err;
*status_vector = isc_arg_end;
return false;
}
// Link the new buffer into the chain of buffers
run->run_buff_alloc = 1;
run->run_record =
reinterpret_cast<sort_record*>(run->run_end_buffer =
run->run_buffer + size);
}
scb->scb_flags |= scb_sorted;
return true;
}
ULONG SORT_write_block(ISC_STATUS* status_vector,
sort_work_file* sfb, ULONG seek, BLOB_PTR* address, ULONG length)
{
/**************************************
*
* S O R T _ w r i t e _ b l o c k
*
**************************************
*
* Functional description
* Write a block of stuff to the scratch file.
*
**************************************/
ULONG write_len, i;
#ifdef DEBUG_SORT_TRACE
write_trace("Write", sfb, seek, address, length);
#endif
// Check out of engine on sort I/O
THREAD_EXIT();
// The following is a crock induced by a VMS C bug
while (length) {
ULONG len = length;
for (i = 0; i < IO_RETRY; i++) {
if (lseek(sfb->sfb_file, LSEEK_OFFSET_CAST seek, SEEK_SET) == -1) {
THREAD_ENTER();
SORT_error(status_vector, sfb, "lseek", isc_io_write_err,
errno);
}
if ((write_len = write(sfb->sfb_file, address, len)) == len)
break;
else {
if (write_len >= 0)
// If write returns value that is not equal len, then
// most likely there is not enough space, try to write
// one more time to get meaningful errno
write_len = write(sfb->sfb_file, address + write_len,
len - write_len);
if ((SSHORT) write_len == -1 && !SYSCALL_INTERRUPTED(errno)) {
THREAD_ENTER();
SORT_error(status_vector, sfb, "write", isc_io_write_err,
errno);
}
}
}
if (i == IO_RETRY) {
THREAD_ENTER();
SORT_error(status_vector, sfb, "write", isc_io_write_err, errno);
}
length -= write_len;
address += write_len;
seek += write_len;
}
THREAD_ENTER();
return seek;
}
static UCHAR *sort_alloc(sort_context* scb, ULONG size)
{
/**************************************
*
* a l l o c
*
**************************************
*
* Functional description
* Allocate and zero a block of memory.
*
* Notes about memory management in this module.
* - Apparently this historical reason (from Deej) that this
* module uses ALL_malloc directly, instead of the JRD allocator
* is so a large sort will not push up the high-water mark of
* memory allocated to a request or attachment (recall this memory
* isn't released until the request/attachment finished)
* - As a result, the memory blocks allocated here don't have
* the blk_header structure (we'ld have to add it if we ever
* change this)
* - Most things allocated have pointers placed in the sort_context.
* (sort control block)
* - There is an error handler set up by our caller, which will
* call back to SORT_fini(), which frees all the memory
* chains that hang off the sort_context.
* - There are some short-term allocations done (for instance,
* when sorting a run_control before writing it to disk). There appears
* to be no need to have an error handler to free them as
* no errors can be posted during the process.
*
* 1994-October-11 David Schnepper
*
**************************************/
UCHAR* const block =
reinterpret_cast<UCHAR*>(gds__alloc(size));
// FREE: caller responsible for freeing
if (!block)
{
error_memory(scb);
return NULL;
}
memset(block, 0, size);
return block;
}
#ifndef SCROLLABLE_CURSORS
#ifdef WORDS_BIGENDIAN
static void diddle_key(UCHAR * record, sort_context* scb, bool direction)
{
/**************************************
*
* d i d d l e _ k e y ( n o n - V A X )
*
**************************************
*
* Functional description
* Perform transformation between the natural form of a record
* and a form that can be sorted in unsigned comparison order.
*
* direction - TRUE for SORT_put() and FALSE for SORT_get()
*
**************************************/
UCHAR *fill_pos, fill_char;
USHORT l, fill, flag;
for (sort_key_def* key = scb->scb_description, *end = key + scb->scb_keys;
key < end; key++)
{
UCHAR* p = record + key->skd_offset;
USHORT n = key->skd_length;
USHORT complement = key->skd_flags & SKD_descending;
switch (key->skd_dtype) {
case SKD_ulong:
case SKD_ushort:
case SKD_bytes:
case SKD_sql_time:
break;
// Stash embedded control info for non-fixed data types in the sort
// record and zap it so that it doesn't interfere with collation
case SKD_varying:
if (direction) {
if (!(scb->scb_flags & scb_sorted)) {
*((USHORT *) (record + key->skd_vary_offset)) =
((vary*) p)->vary_length;
fill_char =
(key->skd_flags & SKD_binary) ? 0 : ASCII_SPACE;
fill_pos = p + sizeof(USHORT) + ((vary*) p)->vary_length;
fill = n - sizeof(USHORT) - ((vary*) p)->vary_length;
if (fill)
memset(fill_pos, fill_char, fill);
}
((vary*) p)->vary_length = 0;
}
break;
case SKD_cstring:
if (direction) {
fill_char = (key->skd_flags & SKD_binary) ? 0 : ASCII_SPACE;
if (!(scb->scb_flags & scb_sorted)) {
*((USHORT *) (record + key->skd_vary_offset)) = l =
strlen((char*)p);
fill_pos = p + l;
fill = n - l;
if (fill)
memset(fill_pos, fill_char, fill);
}
else {
l = *((USHORT *) (record + key->skd_vary_offset));
*(p + l) = fill_char;
}
}
break;
case SKD_text:
break;
#ifndef VMS
case SKD_d_float:
#else
Deliberate_compile_error++;
Fix for any VMS port.
#endif
case SKD_float:
case SKD_double:
flag = (direction || !complement)
? direction : TRUE;
if (flag ^ (*p >> 7))
*p ^= 1 << 7;
else
complement = !complement;
break;
case SKD_long:
case SKD_short:
case SKD_quad:
case SKD_timestamp1:
case SKD_timestamp2:
case SKD_sql_date:
case SKD_int64:
*p ^= 1 << 7;
break;
default:
fb_assert(false);
break;
}
if (complement && n)
do
*p++ ^= -1;
while (--n);
// Flatter but don't complement control info for non-fixed
// data types when restoring the data
if (key->skd_dtype == SKD_varying && !direction) {
p = record + key->skd_offset;
((vary*) p)->vary_length = *((USHORT *) (record + key->skd_vary_offset));
}
if (key->skd_dtype == SKD_cstring && !direction) {
p = record + key->skd_offset;
l = *((USHORT *) (record + key->skd_vary_offset));
*(p + l) = 0;
}
}
}
#else
static void diddle_key(UCHAR * record, sort_context* scb, bool direction)
{
/**************************************
*
* d i d d l e _ k e y ( V A X )
*
**************************************
*
* Functional description
* Perform transformation between the natural form of a record
* and a form that can be sorted in unsigned comparison order.
*
* direction - TRUE for SORT_put() and FALSE for SORT_get()
*
**************************************/
UCHAR c1, fill_char, *fill_pos;
USHORT l, fill;
SSHORT longs, flag;
ULONG lw;
#ifdef VMS
double *dp;
#endif
#ifndef IEEE
USHORT w;
#endif
for (sort_key_def* key = scb->scb_description, *end = key + scb->scb_keys;
key < end; key++)
{
BLOB_PTR* p = (BLOB_PTR *) record + key->skd_offset;
USHORT* wp = (USHORT *) p;
SORTP* lwp = (SORTP *) p;
USHORT complement = key->skd_flags & SKD_descending;
USHORT n = ROUNDUP(key->skd_length, sizeof(SLONG));
switch (key->skd_dtype) {
case SKD_timestamp1:
case SKD_timestamp2:
case SKD_sql_time:
case SKD_sql_date:
p[3] ^= 1 << 7;
break;
case SKD_ulong:
case SKD_ushort:
break;
case SKD_text:
case SKD_bytes:
case SKD_cstring:
case SKD_varying:
// Stash embedded control info for non-fixed data types in the sort
// record and zap it so that it doesn't interfere with collation
if (key->skd_dtype == SKD_varying && direction) {
if (!(scb->scb_flags & scb_sorted)) {
*((USHORT *) (record + key->skd_vary_offset)) = l =
((vary*) p)->vary_length;
fill_char =
(key->skd_flags & SKD_binary) ? 0 : ASCII_SPACE;
fill_pos = p + sizeof(USHORT) + l;
fill = n - sizeof(USHORT) - l;
if (fill)
memset(fill_pos, fill_char, fill);
}
((vary*) p)->vary_length = 0;
}
if (key->skd_dtype == SKD_cstring && direction) {
fill_char = (key->skd_flags & SKD_binary) ? 0 : ASCII_SPACE;
if (!(scb->scb_flags & scb_sorted)) {
*((USHORT *) (record + key->skd_vary_offset)) = l =
strlen(reinterpret_cast<const char*>(p));
fill_pos = p + l;
fill = n - l;
if (fill)
memset(fill_pos, fill_char, fill);
}
else {
l = *((USHORT *) (record + key->skd_vary_offset));
*(p + l) = fill_char;
}
}
longs = n >> SHIFTLONG;
while (--longs >= 0) {
c1 = p[3];
p[3] = *p;
*p++ = c1;
c1 = p[1];
p[1] = *p;
*p = c1;
p += 3;
}
p = (BLOB_PTR *) wp;
break;
case SKD_short:
p[1] ^= 1 << 7;
break;
case SKD_long:
p[3] ^= 1 << 7;
break;
case SKD_quad:
p[7] ^= 1 << 7;
break;
case SKD_int64:
// INT64's fit in TWO LONGS, and hence the SWAP has to happen
// here for the right order comparison using DO_32_COMPARE
if (!direction)
SWAP_LONGS(lwp[0], lwp[1], lw);
p[7] ^= 1 << 7;
if (direction)
SWAP_LONGS(lwp[0], lwp[1], lw);
break;
#ifdef IEEE
case SKD_double:
if (!direction) {
lw = lwp[0];
lwp[0] = lwp[1];
lwp[1] = lw;
}
flag = (direction || !complement) ? direction : TRUE;
if (flag ^ (p[7] >> 7))
p[7] ^= 1 << 7;
else
complement = !complement;
if (direction) {
lw = lwp[0];
lwp[0] = lwp[1];
lwp[1] = lw;
}
break;
case SKD_float:
flag = (direction || !complement) ? direction : TRUE;
if (flag ^ (p[3] >> 7))
p[3] ^= 1 << 7;
else
complement = !complement;
break;
#else // IEEE
#ifdef VMS
case SKD_d_float:
dp = (double *) p;
if (direction)
*dp = MTH$CVT_D_G(dp);
#endif
case SKD_double:
w = wp[2];
wp[2] = wp[3];
wp[3] = w;
#ifndef VMS
case SKD_d_float:
#endif
case SKD_float:
if (!direction)
if (complement) {
if (p[3] & 1 << 7)
complement = !complement;
else
p[3] ^= 1 << 7;
}
else {
if (p[3] & 1 << 7)
p[3] ^= 1 << 7;
else
complement = !complement;
}
w = wp[0];
wp[0] = wp[1];
wp[1] = w;
if (direction)
if (p[3] & 1 << 7)
complement = !complement;
else
p[3] ^= 1 << 7;
#ifdef VMS
else if (key->skd_dtype == SKD_d_float)
*dp = MTH$CVT_G_D(dp);
#endif
break;
#endif // IEEE
default:
// Don't want the debug version to
// stop because of skd_type = 0
// FSG 22.Dez.2000
//
// fb_assert(false);
break;
}
if (complement && n)
do {
*p++ ^= -1;
} while (--n);
// Flatter but don't complement control info for non-fixed
// data types when restoring the data
if (key->skd_dtype == SKD_varying && !direction) {
p = (BLOB_PTR *) record + key->skd_offset;
((vary*) p)->vary_length = *((USHORT *) (record + key->skd_vary_offset));
}
if (key->skd_dtype == SKD_cstring && !direction) {
p = (BLOB_PTR *) record + key->skd_offset;
l = *((USHORT *) (record + key->skd_vary_offset));
*(p + l) = 0;
}
}
}
#endif
#endif
static void error_memory(sort_context* scb)
{
/**************************************
*
* e r r o r _ m e m o r y
*
**************************************
*
* Functional description
* Report fatal out of memory error.
*
**************************************/
ISC_STATUS* status_vector = scb->scb_status_vector;
fb_assert(status_vector != NULL);
*status_vector++ = isc_arg_gds;
*status_vector++ = isc_sort_mem_err;
*status_vector = isc_arg_end;
ERR_punt();
}
static ULONG find_file_space(sort_context* scb, ULONG size, sort_work_file** ret_sfb)
{
/**************************************
*
* f i n d _ f i l e _ s p a c e
*
**************************************
*
* Functional description
* Find space of input size in one of the
* open sort files. If a free block is not
* available, allocate space at the end.
*
**************************************/
TEXT file_name[128];
// Find the best available space. This is defined as the smallest free space
// that is big enough. This preserves large blocks.
work_file_space** best = NULL;
sort_work_file* last_sfb = NULL;
file_name[0] = '\0';
// Search through the available space in the work file list
sort_work_file* best_sfb = 0;
sort_work_file* sfb;
sort_work_file** sfb_ptr;
for (sfb_ptr = &scb->scb_sfb; (sfb = *sfb_ptr); sfb_ptr = &sfb->sfb_next) {
work_file_space* space;
for (work_file_space** ptr = &sfb->sfb_file_space; (space = *ptr);
ptr = &(*ptr)->wfs_next)
{
// If this is smaller than our previous best, use it
if (space->wfs_size >= size &&
(!best || (space->wfs_size < (*best)->wfs_size)))
{
best = ptr;
best_sfb = sfb;
}
}
// Save the previous sfb pointer because when we get out of this
// for loop, sfb would be a NULL pointer
last_sfb = sfb;
}
sfb = last_sfb;
// If we didn't find any space, allocate it at the end of the file
if (!best) {
// If there is no file allocated yet or the size requested is bigger
// than available space in the current directory, create a new file
// and return
if (!sfb || !DLS_get_temp_space(size, sfb) ||
(sfb->sfb_file_size + size >= MAX_TEMPFILE_SIZE))
{
sfb = (sort_work_file*) sort_alloc(scb, (ULONG) sizeof(sort_work_file));
// FREE: scb_sfb chain is freed in local_fini()
// Is the last dir_list at it's size limit? If so, add a new dir_list
// M.E.G
if (last_sfb && (last_sfb->sfb_dls->dls_inuse + size >= MAX_TEMPFILE_SIZE))
if (!DLS_add_dir(MAX_TEMPFILE_SIZE, last_sfb->sfb_dls->dls_directory))
error_memory(scb);
if (last_sfb)
last_sfb->sfb_next = sfb;
else
scb->scb_sfb = sfb;
// Find a free space
sfb->sfb_dls = NULL;
if (!DLS_get_temp_space(size, sfb))
// There is not enough space
error_memory(scb);
// Create a scratch file
sfb->sfb_file =
(int) (IPTR) gds__temp_file(FALSE, SCRATCH, file_name,
sfb->sfb_dls->dls_directory, TRUE);
// allocate the file name even if the file is not open,
// because the error routine depends on it.
// This is released during local_fini()
sfb->sfb_file_name =
FB_NEW(*getDefaultMemoryPool()) char[strlen(file_name) + 1];
// FREE: sfb_file_name is freed in local_fini()
strcpy(sfb->sfb_file_name, file_name);
if (sfb->sfb_file == -1)
SORT_error(scb->scb_status_vector, sfb, "open",
isc_io_open_err, errno);
sfb->sfb_mem = FB_NEW (*getDefaultMemoryPool()) SortMem(sfb, size);
}
*ret_sfb = sfb;
sfb->sfb_file_size += size;
return sfb->sfb_file_size - size;
}
// Set up the return parameters
*ret_sfb = best_sfb;
work_file_space* space = *best;
// If the hunk was an exact fit, remove the work file space block from the
// list and splice it into the free list
if (space->wfs_size == size) {
*best = space->wfs_next;
space->wfs_next = best_sfb->sfb_free_wfs;
best_sfb->sfb_free_wfs = space;
return space->wfs_position;
}
// The best block is too big - chop the needed space off the end
space->wfs_size -= size;
return space->wfs_position + space->wfs_size;
}
static void free_file_space(sort_context* scb, sort_work_file* sfb,
ULONG position, ULONG size)
{
/**************************************
*
* f r e e _ f i l e _ s p a c e
*
**************************************
*
* Functional description
* Release a segment of work file.
*
**************************************/
work_file_space* space;
work_file_space** ptr;
fb_assert(size > 0);
fb_assert(position < sfb->sfb_file_size); // Block starts in file
const ULONG end = position + size;
fb_assert(end <= sfb->sfb_file_size); // Block ends in file
// Search through work file space blocks looking for an adjacent block
for (ptr = &sfb->sfb_file_space; (space = *ptr); ptr = &space->wfs_next) {
if (end >= space->wfs_position)
break;
}
if (space) {
// may have found an adjacent block - try to join them together
if (end == space->wfs_position) {
// newly freed block starts just before previously freed
space->wfs_position -= size;
space->wfs_size += size;
return;
}
if (position == space->wfs_position + space->wfs_size) {
// newly freed block starts just after previously freed
space->wfs_size += size;
work_file_space* next = space->wfs_next;
if (next && end == next->wfs_position) {
// The NEXT freed block is adjacent, join it too
space->wfs_size += next->wfs_size;
space->wfs_next = next->wfs_next;
next->wfs_next = sfb->sfb_free_wfs;
sfb->sfb_free_wfs = next;
}
return;
}
// Blocks weren't adjacent - just nearby
// Check that block to free doesn't overlap existing free block
fb_assert(position >= space->wfs_position + space->wfs_size);
}
/* Block didn't seem to append nicely to an existing block */
if ( (space = sfb->sfb_free_wfs) )
sfb->sfb_free_wfs = space->wfs_next;
else
space = (work_file_space*) sort_alloc(scb, (ULONG) sizeof(work_file_space));
// FREE: wfs_next chain is freed in local_fini()
space->wfs_next = *ptr;
*ptr = space;
space->wfs_size = size;
space->wfs_position = position;
}
static sort_record* get_merge(merge_control* merge, sort_context* scb
#ifdef SCROLLABLE_CURSORS
, RSE_GET_MODE mode
#endif
)
{
/**************************************
*
* g e t _ m e r g e
*
**************************************
*
* Functional description
* Get next record from a merge tree and/or run_control.
*
**************************************/
SORTP *p; // no more than 1 SORTP* to a line
SORTP *q; // no more than 1 SORTP* to a line
ULONG l;
#ifdef SCROLLABLE_CURSORS
ULONG space_available, data_remaining;
#else
ULONG n;
#endif
sort_record* record = NULL;
bool eof = false;
while (merge) {
// If node is a run_control, get the next record (or not) and back to parent
if (merge->mrg_header.rmh_type == TYPE_RUN) {
run_control* run = (run_control*) merge;
merge = run->run_header.rmh_parent;
// check for end-of-file condition in either direction
#ifdef SCROLLABLE_CURSORS
if (
(mode == RSE_get_backward
&& run->run_records >= run->run_max_records - 1)
|| (mode == RSE_get_forward && run->run_records == 0))
#else
if (run->run_records == 0)
#endif
{
record = (sort_record*) - 1;
eof = true;
continue;
}
eof = false;
// Find the appropriate record in the buffer to return
#ifdef SCROLLABLE_CURSORS
if (mode == RSE_get_forward) {
run->run_record = NEXT_RUN_RECORD(run->run_record);
#endif
if ((record = (sort_record*) run->run_record) <
(sort_record*) run->run_end_buffer)
{
#ifndef SCROLLABLE_CURSORS
run->run_record =
reinterpret_cast<sort_record*>(NEXT_RUN_RECORD(run->run_record));
#endif
--run->run_records;
continue;
}
#ifndef SCROLLABLE_CURSORS
// There are records remaining, but the buffer is full.
// Read a buffer full.
l =
(ULONG) ((BLOB_PTR *) run->run_end_buffer -
(BLOB_PTR *) run->run_buffer);
n = run->run_records * scb->scb_longs * sizeof(ULONG);
l = MIN(l, n);
run->run_seek =
run->run_sfb->sfb_mem->read(scb->scb_status_vector,
run->run_seek,
reinterpret_cast<char*>(run->run_buffer),
l);
#else
}
else {
run->run_record = PREV_RUN_RECORD(run->run_record);
if ((record = (sort_record*) run->run_record) >=
run->run_buffer)
{
++run->run_records;
continue;
}
}
// There are records remaining, but we have stepped over the
// edge of the cache. Read the next buffer full of records.
fb_assert((BLOB_PTR *) run->run_end_buffer >
(BLOB_PTR *) run->run_buffer);
space_available =
(ULONG) ((BLOB_PTR *) run->run_end_buffer -
(BLOB_PTR *) run->run_buffer);
if (mode == RSE_get_forward)
data_remaining =
run->run_records * scb->scb_longs * sizeof(ULONG);
else
data_remaining =
(run->run_max_records -
run->run_records) * scb->scb_longs * sizeof(ULONG);
l = MIN(space_available, data_remaining);
if (mode == RSE_get_forward)
run->run_seek += run->run_cached;
else
run->run_seek -= l;
run->run_sfb->sfb_mem->read(run->run_seek, run->run_buffer, l);
run->run_cached = l;
if (mode == RSE_get_forward) {
#endif
record = reinterpret_cast<sort_record*>(run->run_buffer);
#ifndef SCROLLABLE_CURSORS
run->run_record =
reinterpret_cast<sort_record*>(NEXT_RUN_RECORD(record));
#endif
--run->run_records;
#ifdef SCROLLABLE_CURSORS
}
else {
record = PREV_RUN_RECORD(run->run_end_buffer);
++run->run_records;
}
run->run_record = (sort_record*) record;
#endif
continue;
}
// If've we got a record, somebody asked for it. Find out who.
if (record)
if (merge->mrg_stream_a && !merge->mrg_record_a)
if (eof)
merge->mrg_stream_a = NULL;
else
merge->mrg_record_a = record;
else if (eof)
merge->mrg_stream_b = NULL;
else
merge->mrg_record_b = record;
// If either streams need a record and is still active, loop back to pick
// up the record. If either stream is dry, return the record of the other.
// If both are dry, indicate eof for this stream.
record = NULL;
eof = false;
if (!merge->mrg_record_a && merge->mrg_stream_a) {
merge = (merge_control*) merge->mrg_stream_a;
continue;
}
if (!merge->mrg_record_b)
if (merge->mrg_stream_b) {
merge = (merge_control*) merge->mrg_stream_b;
continue;
}
else if ( (record = merge->mrg_record_a) ) {
merge->mrg_record_a = NULL;
merge = merge->mrg_header.rmh_parent;
continue;
}
else {
eof = true;
record = (sort_record*) - 1;
merge = merge->mrg_header.rmh_parent;
continue;
}
if (!merge->mrg_record_a) {
record = merge->mrg_record_b;
merge->mrg_record_b = NULL;
merge = merge->mrg_header.rmh_parent;
continue;
}
// We have prospective records from each of the sub-streams. Compare them.
// If equal, offer each to user routine for possible sacrifice.
p = merge->mrg_record_a->sort_record_key;
q = merge->mrg_record_b->sort_record_key;
l = scb->scb_key_length;
DO_32_COMPARE(p, q, l);
if (l == 0 && scb->scb_dup_callback) {
#ifdef SCROLLABLE_CURSORS
SORT_diddle_key((UCHAR *) merge->mrg_record_a, scb, false);
SORT_diddle_key((UCHAR *) merge->mrg_record_b, scb, false);
#else
diddle_key((UCHAR *) merge->mrg_record_a, scb, false);
diddle_key((UCHAR *) merge->mrg_record_b, scb, false);
#endif
if ((*scb->scb_dup_callback) ((const UCHAR*) merge->mrg_record_a,
(const UCHAR*) merge->mrg_record_b,
scb->scb_dup_callback_arg))
{
merge->mrg_record_a = NULL;
#ifdef SCROLLABLE_CURSORS
SORT_diddle_key((UCHAR *) merge->mrg_record_b, scb, true);
#else
diddle_key((UCHAR *) merge->mrg_record_b, scb, true);
#endif
continue;
}
#ifdef SCROLLABLE_CURSORS
SORT_diddle_key((UCHAR *) merge->mrg_record_a, scb, true);
SORT_diddle_key((UCHAR *) merge->mrg_record_b, scb, true);
#else
diddle_key((UCHAR *) merge->mrg_record_a, scb, true);
diddle_key((UCHAR *) merge->mrg_record_b, scb, true);
#endif
}
#ifdef SCROLLABLE_CURSORS
if (mode == RSE_get_forward && p[-1] < q[-1])
#else
if (p[-1] < q[-1])
#endif
{
record = merge->mrg_record_a;
merge->mrg_record_a = NULL;
}
else {
record = merge->mrg_record_b;
merge->mrg_record_b = NULL;
}
merge = merge->mrg_header.rmh_parent;
}
// Merge pointer is null; we're done. Return either the most
// recent record, or end of file, as appropriate.
return (eof) ? NULL : record;
}
static void init(sort_context* scb)
{
/**************************************
*
* i n i t
*
**************************************
*
* Functional description
* Initialize the sort control block for a quick sort.
*
**************************************/
scb->scb_next_pointer = scb->scb_first_pointer;
scb->scb_last_record = (SR *) scb->scb_end_memory;
*scb->scb_next_pointer++ = reinterpret_cast<sort_record*>(low_key);
}
static bool local_fini(sort_context* scb, Attachment* att)
{
/**************************************
*
* l o c a l _ f i n i
*
**************************************
*
* Functional description
* Finish sort, and release all resources.
*
**************************************/
work_file_space* space;
ULONG** merge_buf;
sort_context** ptr;
bool found_it = true;
if (att) {
// Cover case where a posted error caused reuse by another thread
if (scb->scb_attachment != att)
att = scb->scb_attachment;
found_it = false;
}
// Start by unlinking from que, if present
if (att)
for (ptr = &att->att_active_sorts; *ptr; ptr = &(*ptr)->scb_next)
if (*ptr == scb) {
*ptr = scb->scb_next;
found_it = true;
break;
}
// *NO*. I won't free it if it's not in
// the pointer list that has been passed
// to me. THIS MEANS MEMORY LEAK. -- mrs
if (!found_it)
return false;
// Loop through the sfb list and close work files
sort_work_file* sfb;
while ( (sfb = scb->scb_sfb) ) {
scb->scb_sfb = sfb->sfb_next;
DLS_put_temp_space(sfb);
delete sfb->sfb_mem;
close(sfb->sfb_file);
if (sfb->sfb_file_name) {
delete[] sfb->sfb_file_name;
sfb->sfb_file_name = NULL;
}
while ( (space = sfb->sfb_free_wfs) ) {
sfb->sfb_free_wfs = space->wfs_next;
gds__free(space);
}
while ( (space = sfb->sfb_file_space) ) {
sfb->sfb_file_space = space->wfs_next;
gds__free(space);
}
gds__free(sfb);
}
// Get rid of extra merge space
while ( (merge_buf = (ULONG **) scb->scb_merge_space) ) {
scb->scb_merge_space = *merge_buf;
gds__free(merge_buf);
}
// If runs are allocated and not in the big block, release them.
// Then release the big block.
if (scb->scb_memory) {
gds__free(scb->scb_memory);
scb->scb_memory = NULL;
}
// Clean up the runs that were used
run_control* run;
while ( (run = scb->scb_runs) ) {
scb->scb_runs = run->run_next;
if (run->run_buff_alloc)
gds__free(run->run_buffer);
gds__free(run);
}
// Clean up the free runs also
while ( (run = scb->scb_free_runs) ) {
scb->scb_free_runs = run->run_next;
if (run->run_buff_alloc)
gds__free(run->run_buffer);
gds__free(run);
}
if (scb->scb_merge_pool) {
gds__free(scb->scb_merge_pool);
scb->scb_merge_pool = NULL;
}
scb->scb_merge = NULL;
scb->scb_attachment = NULL;
scb->scb_impure = NULL;
scb->scb_next = NULL;
return true;
}
static void merge_runs(sort_context* scb, USHORT n)
{
/**************************************
*
* m e r g e _ r u n s
*
**************************************
*
* Functional description
* Merge the first n runs hanging off the sort control block, pushing
* the resulting run back onto the sort control block.
*
**************************************/
USHORT count;
merge_control blks[32];
fb_assert((n - 1) <= FB_NELEM(blks)); // stack var big enough?
scb->scb_longs -= SIZEOF_SR_BCKPTR_IN_LONGS;
// Make a pass thru the runs allocating buffer space, computing work file
// space requirements, and filling in a vector of streams with run pointers
const USHORT rec_size = scb->scb_longs << SHIFTLONG;
const USHORT buffers = scb->scb_size_memory / rec_size;
ULONG size = rec_size * (buffers / (USHORT) (2 * n));
BLOB_PTR* buffer = (BLOB_PTR *) scb->scb_first_pointer;
run_control temp_run;
temp_run.run_end_buffer =
(SORTP *) (buffer + (scb->scb_size_memory / rec_size) * rec_size);
temp_run.run_size = 0;
temp_run.run_buff_alloc = 0;
run_merge_hdr* streams[32];
run_merge_hdr** m1 = streams;
run_control* run;
for (run = scb->scb_runs, count = 0; count < n;
run = run->run_next, count++)
{
*m1++ = (run_merge_hdr*) run;
// size = 0 indicates the record is too big to divvy up the
// big sort buffer, so separate buffers must be allocated
if (!size) {
if (!run->run_buff_alloc) {
run->run_buffer =
(ULONG *) gds__alloc((SLONG) rec_size * 2);
// FREE: smb_merge_space freed in local_fini() when sort_context released
if (!run->run_buffer)
error_memory(scb);
run->run_buff_alloc = 1;
}
run->run_end_buffer =
reinterpret_cast<ULONG*>((BLOB_PTR *) run->run_buffer + (rec_size * 2));
run->run_record =
reinterpret_cast<sort_record*>(run->run_end_buffer);
}
else {
run->run_buffer = (ULONG *) buffer;
buffer += size;
run->run_record =
reinterpret_cast<sort_record*>(run->run_end_buffer =
(ULONG *) buffer);
}
temp_run.run_size += run->run_size;
}
temp_run.run_record = reinterpret_cast<sort_record*>(buffer);
temp_run.run_buffer = reinterpret_cast<ULONG*>(temp_run.run_record);
// Build merge tree bottom up.
//
// See also kissing cousin of this loop in SORT_sort()
merge_control* merge;
for (count = n, merge = blks; count > 1;) {
run_merge_hdr** m2 = m1 = streams;
while (count >= 2) {
merge->mrg_header.rmh_type = TYPE_MRG;
fb_assert(((*m1)->rmh_type == TYPE_MRG) || // garbage watch
((*m1)->rmh_type == TYPE_RUN));
(*m1)->rmh_parent = merge;
merge->mrg_stream_a = *m1++;
fb_assert(((*m1)->rmh_type == TYPE_MRG) || // garbage watch
((*m1)->rmh_type == TYPE_RUN));
(*m1)->rmh_parent = merge;
merge->mrg_stream_b = *m1++;
merge->mrg_record_a = NULL;
merge->mrg_record_b = NULL;
*m2++ = (run_merge_hdr*) merge;
merge++;
count -= 2;
}
if (count)
*m2++ = *m1++;
count = m2 - streams;
}
--merge;
merge->mrg_header.rmh_parent = NULL;
// Merge records into run
sort_record* q = reinterpret_cast<sort_record*>(temp_run.run_buffer);
ULONG seek = temp_run.run_seek =
find_file_space(scb, temp_run.run_size, &temp_run.run_sfb);
temp_run.run_records = 0;
const sort_record* p;
#ifdef SCROLLABLE_CURSORS
while (p = get_merge(merge, scb, RSE_get_forward))
#else
while ( (p = get_merge(merge, scb)) )
#endif
{
if (q >= (sort_record*) temp_run.run_end_buffer) {
size = (BLOB_PTR *) q - (BLOB_PTR *) temp_run.run_buffer;
seek = temp_run.run_sfb->sfb_mem->write(scb->scb_status_vector, seek,
reinterpret_cast<char*>(temp_run.run_buffer),
size);
q = reinterpret_cast<sort_record*>(temp_run.run_buffer);
}
count = scb->scb_longs;
do {
*q++ = *p++;
} while (--count);
++temp_run.run_records;
}
#ifdef SCROLLABLE_CURSORS
temp_run.run_max_records = temp_run.run_records;
#endif
// Write the tail of the new run and return any unused space
if ( (size = (BLOB_PTR *) q - (BLOB_PTR *) temp_run.run_buffer) )
seek = temp_run.run_sfb->sfb_mem->write(scb->scb_status_vector, seek,
reinterpret_cast<char*>(temp_run.run_buffer),
size);
// If the records did not fill the allocated run (such as when duplicates are
// rejected), then free the remainder and diminish the size of the run accordingly
if (seek - temp_run.run_seek < temp_run.run_size) {
free_file_space(scb, temp_run.run_sfb, seek,
temp_run.run_seek + temp_run.run_size - seek);
temp_run.run_size = seek - temp_run.run_seek;
}
// Make a final pass thru the runs releasing space, blocks, etc.
for (count = 0; count < n; count++) {
// Remove run from list of in-use run blocks
run = scb->scb_runs;
scb->scb_runs = run->run_next;
#ifdef SCROLLABLE_CURSORS
seek = run->run_seek + run->run_cached - run->run_size;
#else
seek = run->run_seek - run->run_size;
#endif
// Free the sort file space associated with the run
free_file_space(scb, run->run_sfb, seek, run->run_size);
// Add run descriptor to list of unused run descriptor blocks
run->run_next = scb->scb_free_runs;
scb->scb_free_runs = run;
}
scb->scb_free_runs = run->run_next;
if (run->run_buff_alloc) {
gds__free(run->run_buffer);
run->run_buff_alloc = 0;
}
temp_run.run_header.rmh_type = TYPE_RUN;
temp_run.run_depth = run->run_depth;
*run = temp_run;
run->run_next = scb->scb_runs;
++run->run_depth;
scb->scb_runs = run;
scb->scb_longs += SIZEOF_SR_BCKPTR_IN_LONGS;
}
static void quick(SLONG size, SORTP** pointers, ULONG length)
{
/**************************************
*
* q u i c k
*
**************************************
*
* Functional description
* Sort an array of record pointers. The routine assumes the
* following:
*
* a. Each element in the array points to the key of a record.
*
* b. Keys can be compared by auto-incrementing unsigned longword
* compares.
*
* c. Relative array positions "-1" and "size" point to guard records
* containing the least and the greatest possible sort keys.
*
* ***************************************************************
* * Boy, did the assumption below turn out to be pretty stupid! *
* ***************************************************************
*
* Note: For the time being, the key length field is ignored on the
* assumption that something will eventually stop the comparison.
*
* WARNING: THIS ROUTINE DOES NOT MAKE A FINAL PASS TO UNSCRAMBLE
* PARITIONS OF SIZE TWO. THE POINTER ARRAY REQUIRES ADDITIONAL
* PROCESSING BEFORE IT MAY BE USED!
*
**************************************/
SORTP* temp;
#define exchange(x, y) {temp = x; x = y; y = temp;}
SORTP** stack_lower[50];
SORTP*** sl = stack_lower;
SORTP** stack_upper[50];
SORTP*** su = stack_upper;
*sl++ = pointers;
*su++ = pointers + size - 1;
while (sl > stack_lower) {
// Pick up the next interval off the respective stacks
SORTP** r = *--sl;
SORTP** j = *--su;
// Compute the interval. If two or less, defer the sort to a final pass.
const SLONG interval = j - r;
if (interval < 2)
continue;
// Go guard against pre-ordered data, swap the first record with the
// middle record. This isn't perfect, but it is cheap.
SORTP** i = r + interval / 2;
((SORTP ***) (*r))[-1] = i;
((SORTP ***) (*i))[-1] = r;
exchange(*r, *i);
// Prepare to do the partition. Pick up the first longword of the
// key to speed up comparisons.
i = r + 1;
const ULONG key = **r;
// From each end of the interval converge to the middle swapping out of
// parition records as we go. Stop when we converge.
while (true) {
while (**i < key)
i++;
if (**i == key)
while (true) {
const SORTP* p = *i;
const SORTP* q = *r;
ULONG tl = length - 1;
while (tl && *p == *q) {
p++;
q++;
tl--;
}
if (tl && *p > *q)
break;
i++;
}
while (**j > key)
j--;
if (**j == key)
while (j != r) {
const SORTP* p = *j;
const SORTP* q = *r;
ULONG tl = length - 1;
while (tl && *p == *q) {
p++;
q++;
tl--;
}
if (tl && *p < *q)
break;
j--;
}
if (i >= j)
break;
((SORTP ***) (*i))[-1] = j;
((SORTP ***) (*j))[-1] = i;
exchange(*i, *j);
i++;
j--;
}
// We have formed two partitions, separated by a slot for the
// initial record "r". Exchange the record currently in the
// slot with "r".
((SORTP ***) (*r))[-1] = j;
((SORTP ***) (*j))[-1] = r;
exchange(*r, *j);
// Finally, stack the two intervals, longest first
i = *su;
if ((j - r) > (i - j + 1)) {
*sl++ = r;
*su++ = j - 1;
*sl++ = j + 1;
*su++ = i;
}
else {
*sl++ = j + 1;
*su++ = i;
*sl++ = r;
*su++ = j - 1;
}
}
}
static ULONG order(sort_context* scb)
{
/**************************************
*
* o r d e r
*
**************************************
*
* Functional description
* The memoryfull of record pointers have been sorted, but more
* records remain, so the run will have to be written to disk. To
* speed this up, re-arrange the records in physical order so they
* can be written with a single disk write.
*
**************************************/
sort_record** ptr = scb->scb_first_pointer + 1; // 1st ptr is low key
// Last inserted record, also the top of the memory where SORT_RECORDS can
// be written
sort_record* output = reinterpret_cast<sort_record*>(scb->scb_last_record);
sort_ptr_t* lower_limit = reinterpret_cast<sort_ptr_t*>(output);
ULONG temp[1024];
SORTP* buffer = 0;
if ((scb->scb_longs * sizeof(ULONG)) > sizeof(temp))
buffer =
(ULONG *) gds__alloc((SLONG) (scb->scb_longs * sizeof(ULONG)));
// FREE: buffer is freed later in this routine
else
buffer = temp;
if (!buffer)
error_memory(scb);
// Check out the engine
THREAD_EXIT();
// Length of the key part of the record
const SSHORT length = scb->scb_longs - SIZEOF_SR_BCKPTR_IN_LONGS;
// scb_next_pointer points to the end of pointer memory or the beginning of
// records
while (ptr < scb->scb_next_pointer) {
// If the next pointer is null, it's record has been eliminated as a
// duplicate. This is the only easy case.
SR* record = reinterpret_cast<SR*>(*ptr++);
if (!record)
continue;
// Make record point back to the starting of SR struct,
// as all scb* pointer point to the key_id locations!
record =
reinterpret_cast<SR*>(((SORTP *) record) - SIZEOF_SR_BCKPTR_IN_LONGS);
// If the lower limit of live records points to a deleted or used record,
// advance the lower limit
while (!*(lower_limit)
&& (lower_limit < (sort_ptr_t*) scb->scb_end_memory))
{
lower_limit =
reinterpret_cast<sort_ptr_t*>(((SORTP *) lower_limit) + scb->scb_longs);
}
// If the record we want to move won't interfere with lower active
// record, just move the record into position
if (record->sr_sort_record.sort_record_key == (ULONG *) lower_limit) {
MOVE_32(length, record->sr_sort_record.sort_record_key, output);
output =
reinterpret_cast<sort_record*>((SORTP *) output + length);
continue;
}
if (((SORTP *) output) + scb->scb_longs - 1 <= (SORTP *) lower_limit) {
// null the bckptr for this record
record->sr_bckptr = NULL;
MOVE_32(length, record->sr_sort_record.sort_record_key, output);
output =
reinterpret_cast<sort_record*>((SORTP *) output + length);
continue;
}
// There's another record sitting where we want to put our record. Move
// the next logical record to a temp, move the lower limit record to the
// next record's old position (adjusting pointers as we go), then move
// the current record to output.
MOVE_32(length, (SORTP *) record->sr_sort_record.sort_record_key,
buffer);
**((sort_ptr_t***) lower_limit) =
reinterpret_cast<sort_ptr_t*>(record->sr_sort_record.sort_record_key);
MOVE_32(scb->scb_longs, lower_limit, record);
lower_limit = (sort_ptr_t*) ((SORTP *) lower_limit + scb->scb_longs);
MOVE_32(length, buffer, output);
output =
reinterpret_cast<sort_record*>((sort_ptr_t*) ((SORTP *) output + length));
}
// Check back into the engine
THREAD_ENTER();
// It's OK to free this after checking back into the engine, there's
// only fatal failures possible there
if (buffer != temp)
if (buffer != NULL)
gds__free(buffer);
return (((SORTP *) output) -
((SORTP *) scb->scb_last_record)) / (scb->scb_longs -
SIZEOF_SR_BCKPTR_IN_LONGS);
}
static void put_run(sort_context* scb)
{
/**************************************
*
* p u t _ r u n
*
**************************************
*
* Functional description
* Memory has been exhausted. Do a sort on what we have and write
* it to the scratch file. Keep in mind that since duplicate records
* may disappear, the number of records in the run may be less than
* were sorted.
*
**************************************/
run_control* run = scb->scb_free_runs;
if (run)
scb->scb_free_runs = run->run_next;
else {
run = (run_control*) sort_alloc(scb, (ULONG) sizeof(run_control));
// FREE: run will be either on the scb_runs or scb_free_runs list,
// which are freed in local_fini()
}
run->run_next = scb->scb_runs;
scb->scb_runs = run;
run->run_header.rmh_type = TYPE_RUN;
run->run_depth = 0;
// Do the in-core sort. The first phase a duplicate handling we be performed
// in "sort".
sort(scb);
// Re-arrange records in physical order so they can be dumped in a single write
// operation
#ifdef SCROLLABLE_CURSORS
run->run_records = run->run_max_records = order(scb);
run->run_cached = 0;
#else
run->run_records = order(scb);
#endif
// Write records to scratch file. Keep track of the number of bytes
// written, etc.
run->run_size =
run->run_records * (scb->scb_longs -
SIZEOF_SR_BCKPTR_IN_LONGS) * sizeof(ULONG);
run->run_seek = find_file_space(scb, run->run_size, &run->run_sfb);
run->run_sfb->sfb_mem->write(scb->scb_status_vector, run->run_seek,
reinterpret_cast<char*>(scb->scb_last_record),
run->run_size);
}
static void sort(sort_context* scb)
{
/**************************************
*
* s o r t
*
**************************************
*
* Functional description
* Set up for and call quick sort. Quicksort, by design, doesn't
* order partitions of length 2, so make a pass thru the data to
* straighten out pairs. While we at it, if duplicate handling has
* been requested, detect and handle them.
*
**************************************/
SORTP* temp;
// Check out the engine
THREAD_EXIT();
// First, insert a pointer to the high key
*scb->scb_next_pointer = reinterpret_cast<sort_record*>(high_key);
// Next, call QuickSort. Keep in mind that the first pointer is the
// low key and not a record.
SORTP** j = (SORTP **) (scb->scb_first_pointer) + 1;
const ULONG n = (SORTP **) (scb->scb_next_pointer) - j; // calculate # of records
quick(n, j, scb->scb_longs);
// Scream through and correct any out of order pairs
while (j < (SORTP **) scb->scb_next_pointer) {
SORTP** i = j;
j++;
if (**i >= **j) {
const SORTP* p = *i;
const SORTP* q = *j;
ULONG tl = scb->scb_longs - 1;
while (tl && *p == *q) {
p++;
q++;
tl--;
}
if (tl && *p > *q) {
((SORTP ***) (*i))[-1] = j;
((SORTP ***) (*j))[-1] = i;
temp = *i;
*i = *j;
*j = temp;
}
}
}
// If duplicate handling hasn't been requested, we're done
if (!scb->scb_dup_callback) {
// Check back into the engine
THREAD_ENTER();
return;
}
// Make another pass and eliminate duplicates. It's possible to do this
// is the same pass the final ordering, but the logic is complicated enough
// to screw up register optimizations. Better two fast passes than one
// slow pass, I suppose. Prove me wrong and win a trip for two to
// Cleveland, Ohio.
j = reinterpret_cast<SORTP**>(scb->scb_first_pointer + 1);
while (j < (SORTP **) scb->scb_next_pointer) {
SORTP** i = j;
j++;
if (**i != **j)
continue;
const SORTP* p = *i;
const SORTP* q = *j;
ULONG tl = scb->scb_longs - 1;
while (tl && *p == *q) {
p++;
q++;
tl--;
}
if ( (p > *i) && (ULONG) (p - *i) >= scb->scb_key_length ) {
#ifdef SCROLLABLE_CURSORS
SORT_diddle_key((UCHAR *) * i, scb, false);
SORT_diddle_key((UCHAR *) * j, scb, false);
#else
diddle_key((UCHAR *) * i, scb, false);
diddle_key((UCHAR *) * j, scb, false);
#endif
if ((*scb->scb_dup_callback) ((const UCHAR*) *i, (const UCHAR*) *j, scb->scb_dup_callback_arg))
{
((SORTP ***) (*i))[-1] = NULL;
*i = NULL;
}
else
#ifdef SCROLLABLE_CURSORS
SORT_diddle_key((UCHAR *) * i, scb, true);
SORT_diddle_key((UCHAR *) * j, scb, true);
#else
diddle_key((UCHAR *) * i, scb, true);
diddle_key((UCHAR *) * j, scb, true);
#endif
}
}
// Check back into the engine
THREAD_ENTER();
}
#ifdef NOT_USED_OR_REPLACED
#ifdef DEBUG
static void validate(sort_context* scb)
{
/**************************************
*
* v a l i d a t e
*
**************************************
*
* Functional description
* Validate data structures.
*
**************************************/
for (SORTP** ptr = (SORTP **) (scb->scb_first_pointer + 1);
ptr < (SORTP **) scb->scb_next_pointer; ptr++)
{
SORTP* record = *ptr;
if (record[-1] != (SORTP) ptr) {
ISC_STATUS* status_vector = scb->scb_status_vector;
*status_vector++ = isc_arg_gds;
*status_vector++ = isc_crrp_data_err; // Msg360: corruption in data structure
*status_vector = isc_arg_end;
ERR_punt();
}
}
}
#endif
#endif
#ifdef DEBUG_SORT_TRACE
static void write_trace(
UCHAR* operation,
sort_work_file* sfb, ULONG seek, BLOB_PTR* address,
ULONG length)
{
/**************************************
*
* w r i t e _ t r a c e
*
**************************************
*
* Functional description
* Write a trace record.
*
**************************************/
UCHAR file_name[40];
if (!trace_file) {
#if (defined WIN_NT)
strcpy(file_name, "/interbas/stXXXXXX");
#else
strcpy(file_name, "/interbase/DEBUG_SORT_TRACE_XXXXXX");
#endif
#ifdef HAVE_MKSTEMP
const int fd = mkstemp(file_name);
trace_file = fdopen(fd, "w");
#else
mktemp(file_name);
trace_file = fopen(file_name, "w");
#endif
}
if (!trace_file)
return;
UCHAR data[41];
UCHAR* p;
for (p = data; p < data + sizeof(data) - 1; address++)
*p++ = (*address) ? *address : '.';
*p = 0;
fprintf(trace_file, "Fid: %d, %.5s %.7ld - %.7ld\t/%s/\n",
sfb->sfb_file, operation, seek, seek + length, data);
}
#endif
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