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/*-------------------------------------------------------------------------
*
* psort.c--
* Polyphase merge sort.
*
* Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/utils/sort/Attic/psort.c,v 1.12 1997/08/12 20:16:14 momjian Exp $
*
* NOTES
* Sorts the first relation into the second relation.
*
* The old psort.c's routines formed a temporary relation from the merged
* sort files. This version keeps the files around instead of generating the
* relation from them, and provides interface functions to the file so that
* you can grab tuples, mark a position in the file, restore a position in the
* file. You must now explicitly call an interface function to end the sort,
* psort_end, when you are done.
* Now most of the global variables are stuck in the Sort nodes, and
* accessed from there (they are passed to all the psort routines) so that
* each sort running has its own separate state. This is facilitated by having
* the Sort nodes passed in to all the interface functions.
* The one global variable that all the sorts still share is SortMemory.
* You should now be allowed to run two or more psorts concurrently,
* so long as the memory they eat up is not greater than SORTMEM, the initial
* value of SortMemory. -Rex 2.15.1995
*
* Use the tape-splitting method (Knuth, Vol. III, pp281-86) in the future.
*
* Arguments? Variables?
* MAXMERGE, MAXTAPES
*-------------------------------------------------------------------------
*/
#include <stdio.h>
#include <math.h>
#include "postgres.h"
#include "executor/execdebug.h"
#include "access/heapam.h"
#include "access/htup.h"
#include "access/relscan.h"
#include "access/skey.h"
#include "utils/tqual.h" /* for NowTimeQual */
#include "storage/buf.h"
#include "storage/bufmgr.h" /* for BLCKSZ */
#include "utils/portal.h" /* for {Start,End}PortalAllocMode */
#include "utils/elog.h"
#include "utils/rel.h"
#include "nodes/execnodes.h"
#include "nodes/plannodes.h"
#include "executor/executor.h"
#include "utils/lselect.h"
#include "utils/psort.h"
#include "storage/fd.h"
#define TEMPDIR "./"
extern int SortMem; /* defined as postgres option */
static long shortzero = 0; /* used to delimit runs */
/*
* old psort global variables
*
* (These are the global variables from the old psort. They are still used,
* but are now accessed from Sort nodes using the PS macro. Note that while
* these variables will be accessed by PS(node)->whatever, they will still
* be called by their original names within the comments! -Rex 2.10.1995)
*
* LeftistContextData treeContext;
*
* static int TapeRange; // number of tapes - 1 (T) //
* static int Level; // (l) //
* static int TotalDummy; // summation of tp_dummy //
* static struct tape *Tape;
*
* static int BytesRead; // to keep track of # of IO //
* static int BytesWritten;
*
* struct leftist *Tuples; // current tuples in memory //
*
* FILE *psort_grab_file; // this holds tuples grabbed
* from merged sort runs //
* long psort_current; // current file position //
* long psort_saved; // file position saved for
* mark and restore //
*/
/*
* PS - Macro to access and cast psortstate from a Sort node
*/
#define PS(N) ((Psortstate *)N->psortstate)
/*
* psort_begin - polyphase merge sort entry point. Sorts the subplan
* into a temporary file psort_grab_file. After
* this is called, calling the interface function
* psort_grabtuple iteratively will get you the sorted
* tuples. psort_end then finishes the sort off, after
* all the tuples have been grabbed.
*
* Allocates and initializes sort node's psort state.
*/
bool
psort_begin(Sort *node, int nkeys, ScanKey key)
{
bool empty; /* to answer: is child node empty? */
node->psortstate = (struct Psortstate *)palloc(sizeof(struct Psortstate));
if (node->psortstate == NULL)
return false;
AssertArg(nkeys >= 1);
AssertArg(key[0].sk_attno != 0);
AssertArg(key[0].sk_procedure != 0);
PS(node)->BytesRead = 0;
PS(node)->BytesWritten = 0;
PS(node)->treeContext.tupDesc =
ExecGetTupType(outerPlan((Plan *)node));
PS(node)->treeContext.nKeys = nkeys;
PS(node)->treeContext.scanKeys = key;
PS(node)->treeContext.sortMem = SortMem * 1024;
PS(node)->Tuples = NULL;
PS(node)->tupcount = 0;
PS(node)->using_tape_files = false;
PS(node)->memtuples = NULL;
initialrun(node, &empty);
if (empty)
return false;
if (PS(node)->using_tape_files)
PS(node)->psort_grab_file = mergeruns(node);
PS(node)->psort_current = 0;
PS(node)->psort_saved = 0;
return true;
}
/*
* inittapes - initializes the tapes
* - (polyphase merge Alg.D(D1)--Knuth, Vol.3, p.270)
* Returns:
* number of allocated tapes
*/
void
inittapes(Sort *node)
{
register int i;
register struct tape *tp;
Assert(node != (Sort *) NULL);
Assert(PS(node) != (Psortstate *) NULL);
/*
ASSERT(ntapes >= 3 && ntapes <= MAXTAPES,
"inittapes: Invalid number of tapes to initialize.\n");
*/
tp = PS(node)->Tape;
for (i = 0; i < MAXTAPES && (tp->tp_file = gettape()) != NULL; i++) {
tp->tp_dummy = 1;
tp->tp_fib = 1;
tp->tp_prev = tp - 1;
tp++;
}
PS(node)->TapeRange = --tp - PS(node)->Tape;
tp->tp_dummy = 0;
tp->tp_fib = 0;
PS(node)->Tape[0].tp_prev = tp;
if (PS(node)->TapeRange <= 1)
elog(WARN, "inittapes: Could only allocate %d < 3 tapes\n",
PS(node)->TapeRange + 1);
PS(node)->Level = 1;
PS(node)->TotalDummy = PS(node)->TapeRange;
PS(node)->using_tape_files = true;
}
/*
* resetpsort - resets (pfrees) palloc'd memory for an aborted Xaction
*
* Not implemented yet.
*/
void
resetpsort()
{
;
}
/*
* PUTTUP - writes the next tuple
* ENDRUN - mark end of run
* GETLEN - reads the length of the next tuple
* ALLOCTUP - returns space for the new tuple
* SETTUPLEN - stores the length into the tuple
* GETTUP - reads the tuple
*
* Note:
* LEN field must be a short; FP is a stream
*/
#define PUTTUP(NODE, TUP, FP) do {\
((Psortstate *)NODE->psortstate)->BytesWritten += (TUP)->t_len; \
fwrite((char *)TUP, (TUP)->t_len, 1, FP);} while (0)
#define ENDRUN(FP) fwrite((char *)&shortzero, sizeof (shortzero), 1, FP)
#define GETLEN(LEN, FP) fread((char *)&(LEN), sizeof (shortzero), 1, FP)
#define ALLOCTUP(LEN) ((HeapTuple)palloc((unsigned)LEN))
#define GETTUP(NODE, TUP, LEN, FP) do {\
IncrProcessed(); \
((Psortstate *)NODE->psortstate)->BytesRead += (LEN) - sizeof (shortzero); \
fread((char *)(TUP) + sizeof (shortzero), (LEN) - sizeof (shortzero), 1, FP);} \
while (0)
#define SETTUPLEN(TUP, LEN) (TUP)->t_len = LEN
/*
* USEMEM - record use of memory
* FREEMEM - record freeing of memory
* FULLMEM - 1 iff a tuple will fit
*/
#define USEMEM(NODE,AMT) PS(node)->treeContext.sortMem -= (AMT)
#define FREEMEM(NODE,AMT) PS(node)->treeContext.sortMem += (AMT)
#define LACKMEM(NODE) (PS(node)->treeContext.sortMem <= MAXBLCKSZ) /* not accurate */
#define TRACEMEM(FUNC)
#define TRACEOUT(FUNC, TUP)
/*
* initialrun - distributes tuples from the relation
* - (replacement selection(R2-R3)--Knuth, Vol.3, p.257)
* - (polyphase merge Alg.D(D2-D4)--Knuth, Vol.3, p.271)
*
* Explaination:
* Tuples are distributed to the tapes as in Algorithm D.
* A "tuple" with t_size == 0 is used to mark the end of a run.
*
* Note:
* The replacement selection algorithm has been modified
* to go from R1 directly to R3 skipping R2 the first time.
*
* Maybe should use closer(rdesc) before return
* Perhaps should adjust the number of tapes if less than n.
* used--v. likely to have problems in mergeruns().
* Must know if should open/close files before each
* call to psort()? If should--messy??
*
* Possible optimization:
* put the first xxx runs in quickly--problem here since
* I (perhaps prematurely) combined the 2 algorithms.
* Also, perhaps allocate tapes when needed. Split into 2 funcs.
*/
void
initialrun(Sort *node, bool *empty)
{
/* register struct tuple *tup; */
register struct tape *tp;
int baseruns; /* D:(a) */
int extrapasses; /* EOF */
Assert(node != (Sort *) NULL);
Assert(PS(node) != (Psortstate *) NULL);
tp = PS(node)->Tape;
if ((bool)createrun(node, NULL, empty) != false) {
if (! PS(node)->using_tape_files)
inittapes(node);
extrapasses = 0;
}
else {
/* if empty or rows fit in memory, we never access tape stuff */
if (*empty || ! PS(node)->using_tape_files)
return;
if (! PS(node)->using_tape_files)
inittapes(node);
extrapasses = 1 + (PS(node)->Tuples != NULL); /* (T != N) ? 2 : 1 */
}
for ( ; ; ) {
tp->tp_dummy--;
PS(node)->TotalDummy--;
if (tp->tp_dummy < (tp + 1)->tp_dummy)
tp++;
else if (tp->tp_dummy != 0)
tp = PS(node)->Tape;
else {
PS(node)->Level++;
baseruns = PS(node)->Tape[0].tp_fib;
for (tp = PS(node)->Tape;
tp - PS(node)->Tape < PS(node)->TapeRange; tp++) {
PS(node)->TotalDummy +=
(tp->tp_dummy = baseruns
+ (tp + 1)->tp_fib
- tp->tp_fib);
tp->tp_fib = baseruns
+ (tp + 1)->tp_fib;
}
tp = PS(node)->Tape; /* D4 */
} /* D3 */
if (extrapasses)
if (--extrapasses) {
dumptuples(tp->tp_file, node);
ENDRUN(tp->tp_file);
continue;
} else
break;
if ((bool)createrun(node, tp->tp_file, empty) == false)
extrapasses = 1 + (PS(node)->Tuples != NULL);
/* D2 */
}
for (tp = PS(node)->Tape + PS(node)->TapeRange; tp >= PS(node)->Tape; tp--)
rewind(tp->tp_file); /* D. */
}
/*
* createrun - places the next run on file, grabbing the tuples by
* executing the subplan passed in
*
* Uses:
* Tuples, which should contain any tuples for this run
*
* Returns:
* FALSE iff process through end of relation
* Tuples contains the tuples for the following run upon exit
*/
bool
createrun(Sort *node, FILE *file, bool *empty)
{
register HeapTuple lasttuple;
register HeapTuple btup, tup;
struct leftist *nextrun;
Buffer b;
bool foundeor;
short junk;
int cr_tuples = 0; /* Count tuples grabbed from plannode */
TupleTableSlot *cr_slot;
Assert(node != (Sort *) NULL);
Assert(PS(node) != (Psortstate *) NULL);
lasttuple = NULL;
nextrun = NULL;
foundeor = false;
for ( ; ; ) {
while (LACKMEM(node) && PS(node)->Tuples != NULL) {
if (lasttuple != NULL) {
FREEMEM(node,lasttuple->t_len);
FREE(lasttuple);
TRACEMEM(createrun);
}
lasttuple = tup = gettuple(&PS(node)->Tuples, &junk,
&PS(node)->treeContext);
if (! PS(node)->using_tape_files) {
inittapes(node);
if (! file)
file = PS(node)->Tape->tp_file; /* was NULL */
}
PUTTUP(node, tup, file);
TRACEOUT(createrun, tup);
}
if (LACKMEM(node))
break;
/* About to call ExecProcNode, it can mess up the state if it
* eventually calls another Sort node. So must stow it away here for
* the meantime. -Rex 2.2.1995
*/
cr_slot = ExecProcNode(outerPlan((Plan *)node), (Plan *)node);
if (TupIsNull(cr_slot)) {
foundeor = true;
break;
}
else {
tup = tuplecopy(cr_slot->val);
ExecClearTuple(cr_slot);
PS(node)->tupcount++;
cr_tuples++;
}
IncrProcessed();
USEMEM(node,tup->t_len);
TRACEMEM(createrun);
if (lasttuple != NULL && tuplecmp(tup, lasttuple,
&PS(node)->treeContext))
puttuple(&nextrun, tup, 0, &PS(node)->treeContext);
else
puttuple(&PS(node)->Tuples, tup, 0, &PS(node)->treeContext);
}
if (lasttuple != NULL) {
FREEMEM(node,lasttuple->t_len);
FREE(lasttuple);
TRACEMEM(createrun);
}
dumptuples(file, node);
if (PS(node)->using_tape_files)
ENDRUN(file);
/* delimit the end of the run */
PS(node)->Tuples = nextrun;
/* if we did not see any tuples, mark empty */
*empty = (cr_tuples > 0) ? false : true;
return((bool)! foundeor); /* XXX - works iff bool is {0,1} */
}
/*
* tuplecopy - see also tuple.c:palloctup()
*
* This should eventually go there under that name? And this will
* then use palloc directly (see version -r1.2).
*/
HeapTuple
tuplecopy(HeapTuple tup)
{
HeapTuple rettup;
if (!HeapTupleIsValid(tup)) {
return(NULL); /* just in case */
}
rettup = (HeapTuple)palloc(tup->t_len);
memmove((char *)rettup, (char *)tup, tup->t_len); /* XXX */
return(rettup);
}
/*
* mergeruns - merges all runs from input tapes
* (polyphase merge Alg.D(D6)--Knuth, Vol.3, p271)
*
* Returns:
* file of tuples in order
*/
FILE *
mergeruns(Sort *node)
{
register struct tape *tp;
Assert(node != (Sort *) NULL);
Assert(PS(node) != (Psortstate *) NULL);
Assert(PS(node)->using_tape_files == true);
tp = PS(node)->Tape + PS(node)->TapeRange;
merge(node, tp);
rewind(tp->tp_file);
while (--PS(node)->Level != 0) {
tp = tp->tp_prev;
rewind(tp->tp_file);
/* resettape(tp->tp_file); -not sufficient */
merge(node, tp);
rewind(tp->tp_file);
}
return(tp->tp_file);
}
/*
* merge - handles a single merge of the tape
* (polyphase merge Alg.D(D5)--Knuth, Vol.3, p271)
*/
void
merge(Sort *node, struct tape *dest)
{
register HeapTuple tup;
register struct tape *lasttp; /* (TAPE[P]) */
register struct tape *tp;
struct leftist *tuples;
FILE *destfile;
int times; /* runs left to merge */
int outdummy; /* complete dummy runs */
short fromtape;
long tuplen;
Assert(node != (Sort *) NULL);
Assert(PS(node) != (Psortstate *) NULL);
Assert(PS(node)->using_tape_files == true);
lasttp = dest->tp_prev;
times = lasttp->tp_fib;
for (tp = lasttp ; tp != dest; tp = tp->tp_prev)
tp->tp_fib -= times;
tp->tp_fib += times;
/* Tape[].tp_fib (A[]) is set to proper exit values */
if (PS(node)->TotalDummy < PS(node)->TapeRange)/* no complete dummy runs */
outdummy = 0;
else {
outdummy = PS(node)->TotalDummy; /* a large positive number */
for (tp = lasttp; tp != dest; tp = tp->tp_prev)
if (outdummy > tp->tp_dummy)
outdummy = tp->tp_dummy;
for (tp = lasttp; tp != dest; tp = tp->tp_prev)
tp->tp_dummy -= outdummy;
tp->tp_dummy += outdummy;
PS(node)->TotalDummy -= outdummy * PS(node)->TapeRange;
/* do not add the outdummy runs yet */
times -= outdummy;
}
destfile = dest->tp_file;
while (times-- != 0) { /* merge one run */
tuples = NULL;
if (PS(node)->TotalDummy == 0)
for (tp = dest->tp_prev; tp != dest; tp = tp->tp_prev) {
GETLEN(tuplen, tp->tp_file);
tup = ALLOCTUP(tuplen);
USEMEM(node,tuplen);
TRACEMEM(merge);
SETTUPLEN(tup, tuplen);
GETTUP(node, tup, tuplen, tp->tp_file);
puttuple(&tuples, tup, tp - PS(node)->Tape,
&PS(node)->treeContext);
}
else {
for (tp = dest->tp_prev; tp != dest; tp = tp->tp_prev) {
if (tp->tp_dummy != 0) {
tp->tp_dummy--;
PS(node)->TotalDummy--;
} else {
GETLEN(tuplen, tp->tp_file);
tup = ALLOCTUP(tuplen);
USEMEM(node,tuplen);
TRACEMEM(merge);
SETTUPLEN(tup, tuplen);
GETTUP(node, tup, tuplen, tp->tp_file);
puttuple(&tuples, tup, tp - PS(node)->Tape,
&PS(node)->treeContext);
}
}
}
while (tuples != NULL) {
/* possible optimization by using count in tuples */
tup = gettuple(&tuples, &fromtape, &PS(node)->treeContext);
PUTTUP(node, tup, destfile);
FREEMEM(node,tup->t_len);
FREE(tup);
TRACEMEM(merge);
GETLEN(tuplen, PS(node)->Tape[fromtape].tp_file);
if (tuplen == 0)
;
else {
tup = ALLOCTUP(tuplen);
USEMEM(node,tuplen);
TRACEMEM(merge);
SETTUPLEN(tup, tuplen);
GETTUP(node, tup, tuplen, PS(node)->Tape[fromtape].tp_file);
puttuple(&tuples, tup, fromtape, &PS(node)->treeContext);
}
}
ENDRUN(destfile);
}
PS(node)->TotalDummy += outdummy;
}
/*
* dumptuples - stores all the tuples in tree into file
*/
void
dumptuples(FILE *file, Sort *node)
{
register struct leftist *tp;
register struct leftist *newp;
struct leftist **treep = &PS(node)->Tuples;
LeftistContext context = &PS(node)->treeContext;
HeapTuple tup;
int memtupindex = 0;
if (! PS(node)->using_tape_files && PS(node)->tupcount) {
Assert(PS(node)->memtuples == NULL);
PS(node)->memtuples = palloc(PS(node)->tupcount * sizeof(HeapTuple));
}
tp = *treep;
while (tp != NULL) {
tup = tp->lt_tuple;
if (tp->lt_dist == 1) /* lt_right == NULL */
newp = tp->lt_left;
else
newp = lmerge(tp->lt_left, tp->lt_right, context);
FREEMEM(node,sizeof (struct leftist));
FREE(tp);
if (PS(node)->using_tape_files) {
PUTTUP(node, tup, file);
FREEMEM(node,tup->t_len);
FREE(tup);
}
else
PS(node)->memtuples[memtupindex++] = tup;
tp = newp;
}
*treep = NULL;
}
/*
* psort_grabtuple - gets a tuple from the sorted file and returns it.
* If there are no tuples left, returns NULL.
* Should not call psort_end unless this has returned
* a NULL indicating the last tuple has been processed.
*/
HeapTuple
psort_grabtuple(Sort *node)
{
register HeapTuple tup;
long tuplen;
Assert(node != (Sort *) NULL);
Assert(PS(node) != (Psortstate *) NULL);
if (PS(node)->using_tape_files == true) {
if (!feof(PS(node)->psort_grab_file)) {
if (GETLEN(tuplen, PS(node)->psort_grab_file) && tuplen != 0) {
tup = (HeapTuple)palloc((unsigned)tuplen);
SETTUPLEN(tup, tuplen);
GETTUP(node, tup, tuplen, PS(node)->psort_grab_file);
/* Update current merged sort file position */
PS(node)->psort_current += tuplen;
return tup;
}
else
return NULL;
}
else
return NULL;
}
else {
if (PS(node)->psort_current < PS(node)->tupcount)
return PS(node)->memtuples[PS(node)->psort_current++];
else
return NULL;
}
}
/*
* psort_markpos - saves current position in the merged sort file
*/
void
psort_markpos(Sort *node)
{
Assert(node != (Sort *) NULL);
Assert(PS(node) != (Psortstate *) NULL);
PS(node)->psort_saved = PS(node)->psort_current;
}
/*
* psort_restorepos- restores current position in merged sort file to
* last saved position
*/
void
psort_restorepos(Sort *node)
{
Assert(node != (Sort *) NULL);
Assert(PS(node) != (Psortstate *) NULL);
if (PS(node)->using_tape_files == true)
fseek(PS(node)->psort_grab_file, PS(node)->psort_saved, SEEK_SET);
PS(node)->psort_current = PS(node)->psort_saved;
}
/*
* psort_end - unlinks the tape files, and cleans up. Should not be
* called unless psort_grabtuple has returned a NULL.
*/
void
psort_end(Sort *node)
{
register struct tape *tp;
if (!node->cleaned) {
Assert(node != (Sort *) NULL);
/* Assert(PS(node) != (Psortstate *) NULL); */
/*
* I'm changing this because if we are sorting a relation
* with no tuples, psortstate is NULL.
*/
if (PS(node) != (Psortstate *) NULL) {
if (PS(node)->using_tape_files == true)
for (tp = PS(node)->Tape + PS(node)->TapeRange; tp >= PS(node)->Tape; tp--)
destroytape(tp->tp_file);
else if (PS(node)->memtuples)
pfree(PS(node)->memtuples);
NDirectFileRead +=
(int)ceil((double)PS(node)->BytesRead / BLCKSZ);
NDirectFileWrite +=
(int)ceil((double)PS(node)->BytesWritten / BLCKSZ);
pfree((void *)node->psortstate);
node->cleaned = TRUE;
}
}
}
/*
* gettape - handles access temporary files in polyphase merging
*
* Optimizations:
* If guarenteed that only one sort running/process,
* can simplify the file generation--and need not store the
* name for later unlink.
*/
struct tapelst {
char *tl_name;
int tl_fd;
struct tapelst *tl_next;
};
static struct tapelst *Tapes = NULL;
static char Tempfile[MAXPGPATH] = TEMPDIR;
/*
* gettape - returns an open stream for writing/reading
*
* Returns:
* Open stream for writing/reading.
* NULL if unable to open temporary file.
*/
FILE *
gettape()
{
register struct tapelst *tp;
FILE *file;
static int tapeinit = 0;
char *mktemp();
static unsigned int uniqueFileId = 0;
extern int errno;
char uniqueName[MAXPGPATH];
tp = (struct tapelst *)palloc((unsigned)sizeof (struct tapelst));
sprintf(uniqueName, "%spg_psort.%d.%d", TEMPDIR, getpid(), uniqueFileId);
uniqueFileId++;
tapeinit = 1;
tp->tl_name = palloc((unsigned)sizeof(uniqueName));
/*
* now, copy template with final null into palloc'd space
*/
memmove(tp->tl_name, uniqueName, strlen(uniqueName));
AllocateFile();
file = fopen(tp->tl_name, "w+");
if (file == NULL) {
elog(NOTICE, "psort: gettape: fopen returned error code %i", errno);
/* XXX this should not happen */
FreeFile();
FREE(tp->tl_name);
FREE(tp);
return(NULL);
}
tp->tl_fd = fileno(file);
tp->tl_next = Tapes;
Tapes = tp;
return(file);
}
/*
* resettape - resets the tape to size 0
*/
void
resettape(FILE *file)
{
register struct tapelst *tp;
register int fd;
Assert(PointerIsValid(file));
fd = fileno(file);
for (tp = Tapes; tp != NULL && tp->tl_fd != fd; tp = tp->tl_next)
;
if (tp == NULL)
elog(WARN, "resettape: tape not found");
file = freopen(tp->tl_name, "w+", file);
if (file == NULL) {
elog(FATAL, "could not freopen temporary file");
}
}
/*
* distroytape - unlinks the tape
*
* Efficiency note:
* More efficient to destroy more recently allocated tapes first.
*
* Possible bugs:
* Exits instead of returning status, if given invalid tape.
*/
void
destroytape(FILE *file)
{
register struct tapelst *tp, *tq;
register int fd;
if ((tp = Tapes) == NULL)
elog(FATAL, "destroytape: tape not found");
if ((fd = fileno(file)) == tp->tl_fd) {
Tapes = tp->tl_next;
fclose(file);
FreeFile();
unlink(tp->tl_name);
FREE(tp->tl_name);
FREE(tp);
} else
for ( ; ; ) {
if (tp->tl_next == NULL)
elog(FATAL, "destroytape: tape not found");
if (tp->tl_next->tl_fd == fd) {
fclose(file);
FreeFile();
tq = tp->tl_next;
tp->tl_next = tq->tl_next;
unlink(tq->tl_name);
FREE((tq->tl_name));
FREE(tq);
break;
}
tp = tp->tl_next;
}
}