freebsd-nq/contrib/sort/msort.c
2002-04-06 13:49:43 +00:00

391 lines
9.4 KiB
C

/* $NetBSD: msort.c,v 1.10 2001/02/19 20:50:17 jdolecek Exp $ */
/*-
* Copyright (c) 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Peter McIlroy.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "sort.h"
#include "fsort.h"
#ifndef lint
__RCSID("$NetBSD: msort.c,v 1.10 2001/02/19 20:50:17 jdolecek Exp $");
__SCCSID("@(#)msort.c 8.1 (Berkeley) 6/6/93");
#endif /* not lint */
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
/* Subroutines using comparisons: merge sort and check order */
#define DELETE (1)
typedef struct mfile {
u_char *end;
short flno;
struct recheader rec[1];
} MFILE;
static u_char *wts, *wts1 = NULL;
static int cmp __P((RECHEADER *, RECHEADER *));
static int insert __P((struct mfile **, struct mfile **, int, int));
void
fmerge(binno, top, filelist, nfiles, get, outfp, fput, ftbl)
int binno, top;
struct filelist *filelist;
int nfiles;
get_func_t get;
FILE *outfp;
put_func_t fput;
struct field *ftbl;
{
FILE *tout;
int i, j, last;
put_func_t put;
struct tempfile *l_fstack;
wts = ftbl->weights;
if (!UNIQUE && SINGL_FLD && ftbl->flags & F)
wts1 = (ftbl->flags & R) ? Rascii : ascii;
if (!buffer) {
buffer = malloc(bufsize);
if (!buffer)
err(2, "fmerge(): realloc");
if (!linebuf && !SINGL_FLD) {
linebuf_size = DEFLLEN;
linebuf = malloc(linebuf_size);
}
}
if (binno >= 0)
l_fstack = fstack + top;
else
l_fstack = fstack;
while (nfiles) {
put = putrec;
for (j = 0; j < nfiles; j += MERGE_FNUM) {
if (nfiles <= MERGE_FNUM) {
tout = outfp;
put = fput;
}
else
tout = ftmp();
last = min(MERGE_FNUM, nfiles - j);
if (binno < 0) {
for (i = 0; i < last; i++)
if (!(l_fstack[i+MAXFCT-1-MERGE_FNUM].fp =
fopen(filelist->names[j+i], "r")))
err(2, "%s",
filelist->names[j+i]);
merge(MAXFCT-1-MERGE_FNUM, last, get, tout, put, ftbl);
} else {
for (i = 0; i< last; i++)
rewind(l_fstack[i+j].fp);
merge(top+j, last, get, tout, put, ftbl);
}
if (nfiles > MERGE_FNUM)
l_fstack[j/MERGE_FNUM].fp = tout;
}
nfiles = (nfiles + (MERGE_FNUM - 1)) / MERGE_FNUM;
if (nfiles == 1)
nfiles = 0;
if (binno < 0) {
binno = 0;
get = geteasy;
top = 0;
}
}
}
void
merge(infl0, nfiles, get, outfp, put, ftbl)
int infl0, nfiles;
get_func_t get;
put_func_t put;
FILE *outfp;
struct field *ftbl;
{
int c, i, j, nf = nfiles;
struct mfile *flist[MERGE_FNUM], *cfile;
size_t availsz = bufsize;
static void *bufs[MERGE_FNUM+1];
static size_t bufs_sz[MERGE_FNUM+1];
/*
* We need nfiles + 1 buffers. One is 'buffer', the
* rest needs to be allocated.
*/
bufs[0] = buffer;
bufs_sz[0] = bufsize;
for(i=1; i < nfiles+1; i++) {
if (bufs[i])
continue;
bufs[i] = malloc(DEFLLEN);
if (!bufs[i])
err(2, "merge(): realloc");
bufs_sz[i] = DEFLLEN;
}
for (i = j = 0; i < nfiles; i++) {
cfile = (struct mfile *) bufs[j];
cfile->flno = infl0 + j;
cfile->end = (u_char *) bufs[j] + bufs_sz[j];
for (c = 1; c == 1;) {
if (EOF == (c = get(cfile->flno, 0, NULL, nfiles,
cfile->rec, cfile->end, ftbl))) {
--i;
--nfiles;
break;
}
if (c == BUFFEND) {
cfile = realloc(bufs[j], bufs_sz[j] *= 2);
bufs[j] = (void *) cfile;
if (!cfile)
err(2, "merge(): realloc");
cfile->end = (u_char *)cfile + bufs_sz[j];
c = 1;
continue;
}
if (i)
c = insert(flist, &cfile, i, !DELETE);
else
flist[0] = cfile;
}
j++;
}
cfile = (struct mfile *) bufs[nf];
cfile->flno = flist[0]->flno;
cfile->end = (u_char *) cfile + bufs_sz[nf];
while (nfiles) {
for (c = 1; c == 1;) {
if (EOF == (c = get(cfile->flno, 0, NULL, nfiles,
cfile->rec, cfile->end, ftbl))) {
put(flist[0]->rec, outfp);
memmove(flist, flist + 1,
sizeof(MFILE *) * (--nfiles));
cfile->flno = flist[0]->flno;
break;
}
if (c == BUFFEND) {
char *oldbuf = (char *) cfile;
availsz = (char *) cfile->end - oldbuf;
availsz *= 2;
cfile = realloc(oldbuf, availsz);
for(i=0; i < nf+1; i++) {
if (bufs[i] == oldbuf) {
bufs[i] = (char *)cfile;
bufs_sz[i] = availsz;
break;
}
}
if (!cfile)
err(2, "merge: realloc");
cfile->end = (u_char *)cfile + availsz;
c = 1;
continue;
}
if (!(c = insert(flist, &cfile, nfiles, DELETE)))
put(cfile->rec, outfp);
}
}
if (bufs_sz[0] > bufsize) {
buffer = bufs[0];
bufsize = bufs_sz[0];
}
}
/*
* if delete: inserts *rec in flist, deletes flist[0], and leaves it in *rec;
* otherwise just inserts *rec in flist.
*/
static int
insert(flist, rec, ttop, delete)
struct mfile **flist, **rec;
int delete, ttop; /* delete = 0 or 1 */
{
struct mfile *tmprec = *rec;
int mid, top = ttop, bot = 0, cmpv = 1;
for (mid = top/2; bot +1 != top; mid = (bot+top)/2) {
cmpv = cmp(tmprec->rec, flist[mid]->rec);
if (cmpv < 0)
top = mid;
else if (cmpv > 0)
bot = mid;
else {
if (UNIQUE)
break;
if (stable_sort) {
/*
* Apply sort by fileno, to give priority
* to earlier specified files, hence providing
* more stable sort.
* If fileno is same, the new record should
* be put _after_ the previous entry.
*/
cmpv = tmprec->flno - flist[mid]->flno;
if (cmpv >= 0)
bot = mid;
else /* cmpv == 0 */
bot = mid - 1;
} else {
/* non-stable sort */
bot = mid - 1;
}
break;
}
}
if (delete) {
if (UNIQUE) {
if (!bot && cmpv)
cmpv = cmp(tmprec->rec, flist[0]->rec);
if (!cmpv)
return (1);
}
tmprec = flist[0];
if (bot)
memmove(flist, flist+1, bot * sizeof(MFILE **));
flist[bot] = *rec;
*rec = tmprec;
(*rec)->flno = flist[0]->flno;
return (0);
} else {
if (!bot && !(UNIQUE && !cmpv)) {
cmpv = cmp(tmprec->rec, flist[0]->rec);
if (cmpv < 0)
bot = -1;
}
if (UNIQUE && !cmpv)
return (1);
bot++;
memmove(flist + bot+1, flist + bot,
(ttop - bot) * sizeof(MFILE **));
flist[bot] = *rec;
return (0);
}
}
/*
* check order on one file
*/
void
order(filelist, get, ftbl)
struct filelist *filelist;
get_func_t get;
struct field *ftbl;
{
u_char *crec_end, *prec_end, *trec_end;
int c;
RECHEADER *crec, *prec, *trec;
if (!SINGL_FLD)
linebuf = malloc(DEFLLEN);
buffer = malloc(2 * (DEFLLEN + sizeof(TRECHEADER)));
crec = (RECHEADER *) buffer;
crec_end = buffer + DEFLLEN + sizeof(TRECHEADER);
prec = (RECHEADER *) (buffer + DEFLLEN + sizeof(TRECHEADER));
prec_end = buffer + 2*(DEFLLEN + sizeof(TRECHEADER));
wts = ftbl->weights;
if (SINGL_FLD && (ftbl->flags & F))
wts1 = (ftbl->flags & R) ? Rascii : ascii;
else
wts1 = NULL;
if (0 == get(-1, 0, filelist, 1, prec, prec_end, ftbl))
while (0 == get(-1, 0, filelist, 1, crec, crec_end, ftbl)) {
if (0 < (c = cmp(prec, crec))) {
crec->data[crec->length-1] = 0;
errx(1, "found disorder: %s", crec->data+crec->offset);
}
if (UNIQUE && !c) {
crec->data[crec->length-1] = 0;
errx(1, "found non-uniqueness: %s",
crec->data+crec->offset);
}
/*
* Swap pointers so that this record is on place pointed
* to by prec and new record is read to place pointed to by
* crec.
*/
trec = prec;
prec = crec;
crec = trec;
trec_end = prec_end;
prec_end = crec_end;
crec_end = trec_end;
}
exit(0);
}
static int
cmp(rec1, rec2)
RECHEADER *rec1, *rec2;
{
int r;
u_char *pos1, *pos2, *end;
u_char *cwts;
for (cwts = wts; cwts; cwts = (cwts == wts1 ? NULL : wts1)) {
pos1 = rec1->data;
pos2 = rec2->data;
if (!SINGL_FLD && (UNIQUE || stable_sort))
end = pos1 + min(rec1->offset, rec2->offset);
else
end = pos1 + min(rec1->length, rec2->length);
for (; pos1 < end; ) {
if ((r = cwts[*pos1++] - cwts[*pos2++]))
return (r);
}
}
return (0);
}