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

340 lines
9.3 KiB
C

/* $NetBSD: fields.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.
*/
/* Subroutines to generate sort keys. */
#include "sort.h"
#ifndef lint
__RCSID("$NetBSD: fields.c,v 1.10 2001/02/19 20:50:17 jdolecek Exp $");
__SCCSID("@(#)fields.c 8.1 (Berkeley) 6/6/93");
#endif /* not lint */
#define blancmange(ptr) { \
if (BLANK & d_mask[*(ptr)]) \
while (BLANK & d_mask[*(++(ptr))]); \
}
#define NEXTCOL(pos) { \
if (!SEP_FLAG) \
while (BLANK & l_d_mask[*(++pos)]); \
while (!((FLD_D | REC_D_F) & l_d_mask[*++pos])); \
}
static u_char *enterfield __P((u_char *, u_char *, struct field *, int));
static u_char *number __P((u_char *, u_char *, u_char *, u_char *, int));
extern struct coldesc clist[(ND+1)*2];
extern int ncols;
#define DECIMAL '.'
#define OFFSET 128
u_char TENS[10]; /* TENS[0] = REC_D <= 128 ? 130 - '0' : 2 -'0'... */
u_char NEGTENS[10]; /* NEGTENS[0] = REC_D <= 128 ? 126 + '0' : 252 +'0' */
u_char *OFF_TENS, *OFF_NTENS; /* TENS - '0', NEGTENS - '0' */
u_char fnum[NBINS], rnum[NBINS];
/*
* constructs sort key with leading recheader, followed by the key,
* followed by the original line.
*/
length_t
enterkey(keybuf, line, size, fieldtable)
RECHEADER *keybuf; /* pointer to start of key */
DBT *line;
int size;
struct field fieldtable[];
{
int i;
u_char *l_d_mask;
u_char *lineend, *pos;
u_char *endkey, *keypos;
struct coldesc *clpos;
int col = 1;
struct field *ftpos;
l_d_mask = d_mask;
pos = (u_char *) line->data - 1;
lineend = (u_char *) line->data + line->size-1;
/* don't include rec_delimiter */
for (i = 0; i < ncols; i++) {
clpos = clist + i;
for (; (col < clpos->num) && (pos < lineend); col++) {
NEXTCOL(pos);
}
if (pos >= lineend)
break;
clpos->start = SEP_FLAG ? pos + 1 : pos;
NEXTCOL(pos);
clpos->end = pos;
col++;
if (pos >= lineend) {
clpos->end = lineend;
i++;
break;
}
}
for (; i <= ncols; i++)
clist[i].start = clist[i].end = lineend;
if (clist[0].start < (u_char *) line->data)
clist[0].start++;
keypos = keybuf->data;
endkey = (u_char *) keybuf + size - line->size;
for (ftpos = fieldtable + 1; ftpos->icol.num; ftpos++)
if ((keypos = enterfield(keypos, endkey, ftpos,
fieldtable->flags)) == NULL)
return (1);
keybuf->offset = keypos - keybuf->data;
keybuf->length = keybuf->offset + line->size;
if (keybuf->length + sizeof(TRECHEADER) > size) {
/* line too long for buffer */
return (1);
}
/*
* Make [s]radixsort() only sort by relevant part of key if:
* 1. we want to choose unique items by relevant field[s]
* 2. we want stable sort and so the items should be sorted only by
* the relevant field[s]
*/
if (UNIQUE || (stable_sort && keybuf->offset < line->size))
keypos[-1] = REC_D;
memcpy(keybuf->data + keybuf->offset, line->data, line->size);
return (0);
}
/*
* constructs a field (as defined by -k) within a key
*/
static u_char *
enterfield(tablepos, endkey, cur_fld, gflags)
struct field *cur_fld;
u_char *tablepos, *endkey;
int gflags;
{
u_char *start, *end, *lineend, *mask, *lweight;
struct column icol, tcol;
u_int flags;
u_int Rflag;
icol = cur_fld->icol;
tcol = cur_fld->tcol;
flags = cur_fld->flags;
start = icol.p->start;
lineend = clist[ncols].end;
if (flags & BI)
blancmange(start);
start += icol.indent;
start = min(start, lineend);
if (!tcol.num)
end = lineend;
else {
if (tcol.indent) {
end = tcol.p->start;
if (flags & BT)
blancmange(end);
end += tcol.indent;
end = min(end, lineend);
} else
end = tcol.p->end;
}
if (flags & N) {
Rflag = (gflags & R ) ^ (flags & R) ? 1 : 0;
return number(tablepos, endkey, start, end, Rflag);
}
mask = cur_fld->mask;
lweight = cur_fld->weights;
for (; start < end; start++)
if (mask[*start]) {
if (*start <= 1) {
if (tablepos+2 >= endkey)
return (NULL);
*tablepos++ = lweight[1];
*tablepos++ = lweight[*start ? 2 : 1];
} else {
if (tablepos+1 >= endkey)
return (NULL);
*tablepos++ = lweight[*start];
}
}
*tablepos++ = lweight[0];
return (tablepos == endkey ? NULL : tablepos);
}
/* Uses the first bin to assign sign, expsign, 0, and the first
* 61 out of the exponent ( (254 - 3 origins - 4 over/underflows)/4 = 61 ).
* When sorting in forward order:
* use (0-99) -> (130->240) for sorting the mantissa if REC_D <=128;
* else use (0-99)->(2-102).
* If the exponent is >=61, use another byte for each additional 253
* in the exponent. Cutoff is at 567.
* To avoid confusing the exponent and the mantissa, use a field delimiter
* if the exponent is exactly 61, 61+252, etc--this is ok, since it's the
* only time a field delimiter can come in that position.
* Reverse order is done analagously.
*/
static u_char *
number(pos, bufend, line, lineend, Rflag)
u_char *line, *pos, *bufend, *lineend;
int Rflag;
{
int or_sign, parity = 0;
int expincr = 1, exponent = -1;
int bite, expsign = 1, sign = 1;
u_char lastvalue, *nonzero, *tline, *C_TENS;
u_char *nweights;
if (Rflag)
nweights = rnum;
else
nweights = fnum;
if (pos > bufend - 8)
return (NULL);
/*
* or_sign sets the sort direction:
* (-r: +/-)(sign: +/-)(expsign: +/-)
*/
or_sign = sign ^ expsign ^ Rflag;
blancmange(line);
if (*line == '-') { /* set the sign */
or_sign ^= 1;
sign = 0;
line++;
}
/* eat initial zeroes */
for (; *line == '0' && line < lineend; line++)
;
/* calculate exponents < 0 */
if (*line == DECIMAL) {
exponent = 1;
while (*++line == '0' && line < lineend)
exponent++;
expincr = 0;
expsign = 0;
}
/* next character better be a digit */
if (*line < '1' || *line > '9' || line >= lineend) {
*pos++ = nweights[127];
return (pos);
}
if (expincr) {
for (tline = line-1; *++tline >= '0' &&
*tline <= '9' && tline < lineend;)
exponent++;
}
if (exponent > 567) {
*pos++ = nweights[sign ? (expsign ? 254 : 128)
: (expsign ? 0 : 126)];
warnx("exponent out of bounds");
return (pos);
}
bite = min(exponent, 61);
*pos++ = nweights[(sign) ? (expsign ? 189+bite : 189-bite)
: (expsign ? 64-bite : 64+bite)];
if (bite >= 61) {
do {
exponent -= bite;
bite = min(exponent, 254);
*pos++ = nweights[or_sign ? 254-bite : bite];
} while (bite == 254);
}
C_TENS = or_sign ? OFF_NTENS : OFF_TENS;
for (; line < lineend; line++) {
if (*line >= '0' && *line <= '9') {
if (parity) {
*pos++ = C_TENS[lastvalue] + (or_sign ? - *line
: *line);
if (pos == bufend)
return (NULL);
if (*line != '0' || lastvalue != '0')
nonzero = pos;
} else
lastvalue = *line;
parity ^= 1;
} else if(*line == DECIMAL) {
if(!expincr) /* a decimal already occurred once */
break;
expincr = 0;
} else
break;
}
if (parity && lastvalue != '0') {
*pos++ = or_sign ? OFF_NTENS[lastvalue] - '0' :
OFF_TENS[lastvalue] + '0';
} else
pos = nonzero;
if (pos > bufend-1)
return (NULL);
*pos++ = or_sign ? nweights[254] : nweights[0];
return (pos);
}
/* This forces a gap around the record delimiter
* Thus fnum has vaues over (0,254) -> ((0,REC_D-1),(REC_D+1,255));
* rnum over (0,254) -> (255,REC_D+1),(REC_D-1,0))
*/
void
num_init()
{
int i;
TENS[0] = REC_D <=128 ? 130 - '0' : 2 - '0';
NEGTENS[0] = REC_D <=128 ? 126 + '0' : 254 + '0';
OFF_TENS = TENS - '0';
OFF_NTENS = NEGTENS - '0';
for (i = 1; i < 10; i++) {
TENS[i] = TENS[i - 1] + 10;
NEGTENS[i] = NEGTENS[i - 1] - 10;
}
for (i = 0; i < REC_D; i++) {
fnum[i] = i;
rnum[255 - i] = i;
}
for (i = REC_D; i <255; i++) {
fnum[i] = i + 1;
rnum[255 - i] = i - 1;
}
}