OpenBSD-4.6/usr.bin/sort/fsort.c
/* $OpenBSD: fsort.c,v 1.20 2008/11/20 12:14:16 otto 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. 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.
*/
#ifndef lint
#if 0
static char sccsid[] = "@(#)fsort.c 8.1 (Berkeley) 6/6/93";
#else
static char rcsid[] = "$OpenBSD: fsort.c,v 1.20 2008/11/20 12:14:16 otto Exp $";
#endif
#endif /* not lint */
/*
* Read in the next bin. If it fits in one segment sort it;
* otherwise refine it by segment deeper by one character,
* and try again on smaller bins. Sort the final bin at this level
* of recursion to keep the head of fstack at 0.
* After PANIC passes, abort to merge sort.
*/
#include "sort.h"
#include "fsort.h"
#include <stdlib.h>
#include <string.h>
u_char *linebuf;
size_t linebuf_size = MAXLLEN;
struct tempfile fstack[MAXFCT];
#define FSORTMAX 4
int PANIC = FSORTMAX;
void
fsort(int binno, int depth, union f_handle infiles, int nfiles, FILE *outfp,
struct field *ftbl)
{
u_char *weights, **keypos, *bufend, *tmpbuf;
static u_char *buffer, **keylist;
static size_t bufsize;
int ntfiles, mfct = 0, total, i, maxb, lastb, panic = 0;
int c, nelem;
long sizes[NBINS+1];
union f_handle tfiles, mstart = {MAXFCT-16};
int (*get)(int, union f_handle, int, RECHEADER *,
u_char *, struct field *);
RECHEADER *crec;
struct field tfield[2];
FILE *prevfp, *tailfp[FSORTMAX+1];
memset(tailfp, 0, sizeof(tailfp));
prevfp = outfp;
memset(tfield, 0, sizeof(tfield));
if (ftbl[0].flags & R)
tfield[0].weights = Rascii;
else
tfield[0].weights = ascii;
tfield[0].icol.num = 1;
weights = ftbl[0].weights;
if (buffer == NULL) {
bufsize = BUFSIZE;
if ((buffer = malloc(bufsize)) == NULL ||
(keylist = calloc(MAXNUM, sizeof(u_char *))) == NULL)
err(2, NULL);
}
bufend = buffer + bufsize - 1;
if (binno >= 0) {
tfiles.top = infiles.top + nfiles;
get = getnext;
} else {
tfiles.top = 0;
if (SINGL_FLD)
get = makeline;
else
get = makekey;
}
for (;;) {
memset(sizes, 0, sizeof(sizes));
c = ntfiles = 0;
if (binno == weights[REC_D] &&
!(SINGL_FLD && ftbl[0].flags & F)) { /* pop */
rd_append(weights[REC_D],
infiles, nfiles, prevfp, buffer, bufend);
break;
} else if (binno == weights[REC_D]) {
depth = 0; /* start over on flat weights */
ftbl = tfield;
weights = ftbl[0].weights;
}
while (c != EOF) {
keypos = keylist;
nelem = 0;
crec = (RECHEADER *) buffer;
while ((c = get(binno, infiles, nfiles, crec, bufend,
ftbl)) == 0) {
*keypos++ = crec->data + depth;
if (++nelem == MAXNUM) {
c = BUFFEND;
break;
}
crec = (RECHEADER *)((char *)crec +
SALIGN(crec->length) + sizeof(TRECHEADER));
}
/*
* buffer was too small for data, allocate
* a bigger buffer.
*/
if (c == BUFFEND && nelem == 0) {
bufsize *= 2;
tmpbuf = realloc(buffer, bufsize);
if (!tmpbuf)
err(2, "failed to realloc buffer");
crec = (RECHEADER *)
(tmpbuf + ((u_char *)crec - buffer));
buffer = tmpbuf;
bufend = buffer + bufsize - 1;
continue;
}
if (c == BUFFEND || ntfiles || mfct) { /* push */
if (panic >= PANIC) {
fstack[MAXFCT-16+mfct].fp = ftmp();
if (radixsort((const u_char **)keylist,
nelem, weights, REC_D))
err(2, NULL);
append(keylist, nelem, depth, fstack[
MAXFCT-16+mfct].fp, putrec, ftbl);
mfct++;
/* reduce number of open files */
if (mfct == 16 ||(c == EOF && ntfiles)) {
fstack[tfiles.top + ntfiles].fp
= ftmp();
fmerge(0, mstart, mfct, geteasy,
fstack[tfiles.top+ntfiles].fp,
putrec, ftbl);
ntfiles++;
mfct = 0;
}
} else {
fstack[tfiles.top + ntfiles].fp= ftmp();
onepass(keylist, depth, nelem, sizes,
weights, fstack[tfiles.top+ntfiles].fp);
ntfiles++;
}
}
}
get = getnext;
if (!ntfiles && !mfct) { /* everything in memory--pop */
if (nelem > 1) {
if (STABLE) {
i = sradixsort((const u_char **)keylist,
nelem, weights, REC_D);
} else {
i = radixsort((const u_char **)keylist,
nelem, weights, REC_D);
}
if (i)
err(2, NULL);
}
append(keylist, nelem, depth, outfp, putline, ftbl);
break; /* pop */
}
if (panic >= PANIC) {
if (!ntfiles)
fmerge(0, mstart, mfct, geteasy,
outfp, putline, ftbl);
else
fmerge(0, tfiles, ntfiles, geteasy,
outfp, putline, ftbl);
break;
}
total = maxb = lastb = 0; /* find if one bin dominates */
for (i = 0; i < NBINS; i++)
if (sizes[i]) {
if (sizes[i] > sizes[maxb])
maxb = i;
lastb = i;
total += sizes[i];
}
if (sizes[maxb] < max((total / 2) , BUFSIZE))
maxb = lastb; /* otherwise pop after last bin */
fstack[tfiles.top].lastb = lastb;
fstack[tfiles.top].maxb = maxb;
/* start refining next level. */
get(-1, tfiles, ntfiles, crec, bufend, 0); /* rewind */
for (i = 0; i < maxb; i++) {
if (!sizes[i]) /* bin empty; step ahead file offset */
get(i, tfiles, ntfiles, crec, bufend, 0);
else
fsort(i, depth+1, tfiles, ntfiles, outfp, ftbl);
}
if (lastb != maxb) {
if (prevfp != outfp)
tailfp[panic] = prevfp;
prevfp = ftmp();
for (i = maxb+1; i <= lastb; i++)
if (!sizes[i])
get(i, tfiles, ntfiles, crec, bufend,0);
else
fsort(i, depth+1, tfiles, ntfiles,
prevfp, ftbl);
}
/* sort biggest (or last) bin at this level */
depth++;
panic++;
binno = maxb;
infiles.top = tfiles.top; /* getnext will free tfiles, */
nfiles = ntfiles; /* so overwrite them */
}
if (prevfp != outfp) {
concat(outfp, prevfp);
fclose(prevfp);
}
for (i = panic; i >= 0; --i)
if (tailfp[i]) {
concat(outfp, tailfp[i]);
fclose(tailfp[i]);
}
}
/*
* This is one pass of radix exchange, dumping the bins to disk.
*/
#define swap(a, b, t) t = a, a = b, b = t
void
onepass(u_char **a, int depth, long n, long sizes[], u_char *tr, FILE *fp)
{
size_t tsizes[NBINS+1];
u_char **bin[257], **top[256], ***bp, ***bpmax, ***tp;
static int histo[256];
int *hp;
int c;
u_char **an, *t, **aj;
u_char **ak, *r;
memset(tsizes, 0, sizeof(tsizes));
depth += sizeof(TRECHEADER);
an = &a[n];
for (ak = a; ak < an; ak++) {
histo[c = tr[**ak]]++;
tsizes[c] += ((RECHEADER *) (*ak -= depth))->length;
}
bin[0] = a;
bpmax = bin + 256;
tp = top, hp = histo;
for (bp = bin; bp < bpmax; bp++) {
*tp++ = *(bp + 1) = *bp + (c = *hp);
*hp++ = 0;
if (c <= 1)
continue;
}
for (aj = a; aj < an; *aj = r, aj = bin[c + 1])
for (r = *aj; aj < (ak = --top[c = tr[r[depth]]]); )
swap(*ak, r, t);
for (ak = a, c = 0; c < 256; c++) {
an = bin[c + 1];
n = an - ak;
tsizes[c] += n * sizeof(TRECHEADER);
/* tell getnext how many elements in this bin, this segment. */
EWRITE(&tsizes[c], sizeof(size_t), 1, fp);
sizes[c] += tsizes[c];
for (; ak < an; ++ak)
putrec((RECHEADER *) *ak, fp);
}
}