724 lines
15 KiB
C
724 lines
15 KiB
C
/* $NetBSD: units.c,v 1.9 2000/04/14 06:11:11 simonb Exp $ */
|
|
|
|
/*
|
|
* units.c Copyright (c) 1993 by Adrian Mariano (adrian@cam.cornell.edu)
|
|
*
|
|
* 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. The name of the author may not be used to endorse or promote products
|
|
* derived from this software without specific prior written permission.
|
|
* Disclaimer: This software is provided by the author "as is". The author
|
|
* shall not be liable for any damages caused in any way by this software.
|
|
*
|
|
* I would appreciate (though I do not require) receiving a copy of any
|
|
* improvements you might make to this program.
|
|
*/
|
|
|
|
#include <ctype.h>
|
|
#include <err.h>
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
#include <stdlib.h>
|
|
#include <unistd.h>
|
|
|
|
#include "pathnames.h"
|
|
|
|
#define VERSION "1.0"
|
|
|
|
#ifndef UNITSFILE
|
|
#define UNITSFILE _PATH_UNITSLIB
|
|
#endif
|
|
|
|
#define MAXUNITS 1000
|
|
#define MAXPREFIXES 50
|
|
|
|
#define MAXSUBUNITS 500
|
|
|
|
#define PRIMITIVECHAR '!'
|
|
|
|
char *powerstring = "^";
|
|
|
|
struct {
|
|
char *uname;
|
|
char *uval;
|
|
} unittable[MAXUNITS];
|
|
|
|
struct unittype {
|
|
char *numerator[MAXSUBUNITS];
|
|
char *denominator[MAXSUBUNITS];
|
|
double factor;
|
|
};
|
|
|
|
struct {
|
|
char *prefixname;
|
|
char *prefixval;
|
|
} prefixtable[MAXPREFIXES];
|
|
|
|
|
|
char *NULLUNIT = "";
|
|
|
|
int unitcount;
|
|
int prefixcount;
|
|
|
|
|
|
int addsubunit __P((char *[], char *));
|
|
int addunit __P((struct unittype *, char *, int));
|
|
void cancelunit __P((struct unittype *));
|
|
int compare __P((const void *, const void *));
|
|
int compareproducts __P((char **, char **));
|
|
int compareunits __P((struct unittype *, struct unittype *));
|
|
int completereduce __P((struct unittype *));
|
|
void initializeunit __P((struct unittype *));
|
|
int main __P((int, char **));
|
|
void readerror __P((int));
|
|
void readunits __P((char *));
|
|
int reduceproduct __P((struct unittype *, int));
|
|
int reduceunit __P((struct unittype *));
|
|
void showanswer __P((struct unittype *, struct unittype *));
|
|
void showunit __P((struct unittype *));
|
|
void sortunit __P((struct unittype *));
|
|
void usage __P((void));
|
|
void zeroerror __P((void));
|
|
char *dupstr __P((char *));
|
|
char *lookupunit __P((char *));
|
|
|
|
|
|
char *
|
|
dupstr(char *str)
|
|
{
|
|
char *ret;
|
|
|
|
ret = malloc(strlen(str) + 1);
|
|
if (!ret)
|
|
err(3, "Memory allocation error");
|
|
strcpy(ret, str);
|
|
return (ret);
|
|
}
|
|
|
|
|
|
void
|
|
readerror(int linenum)
|
|
{
|
|
warnx("Error in units file '%s' line %d", UNITSFILE, linenum);
|
|
}
|
|
|
|
|
|
void
|
|
readunits(char *userfile)
|
|
{
|
|
FILE *unitfile;
|
|
char line[80], *lineptr;
|
|
int len, linenum, i;
|
|
|
|
unitcount = 0;
|
|
linenum = 0;
|
|
|
|
if (userfile) {
|
|
unitfile = fopen(userfile, "rt");
|
|
if (!unitfile)
|
|
err(1, "Unable to open units file '%s'", userfile);
|
|
}
|
|
else {
|
|
unitfile = fopen(UNITSFILE, "rt");
|
|
if (!unitfile) {
|
|
char *direc, *env;
|
|
char filename[1000];
|
|
char separator[2];
|
|
|
|
env = getenv("PATH");
|
|
if (env) {
|
|
if (strchr(env, ';'))
|
|
strcpy(separator, ";");
|
|
else
|
|
strcpy(separator, ":");
|
|
direc = strtok(env, separator);
|
|
while (direc) {
|
|
strcpy(filename, "");
|
|
strncat(filename, direc, 999);
|
|
strncat(filename, "/",
|
|
999 - strlen(filename));
|
|
strncat(filename, UNITSFILE,
|
|
999 - strlen(filename));
|
|
unitfile = fopen(filename, "rt");
|
|
if (unitfile)
|
|
break;
|
|
direc = strtok(NULL, separator);
|
|
}
|
|
}
|
|
if (!unitfile)
|
|
errx(1, "Can't find units file '%s'",
|
|
UNITSFILE);
|
|
}
|
|
}
|
|
while (!feof(unitfile)) {
|
|
if (!fgets(line, 79, unitfile))
|
|
break;
|
|
linenum++;
|
|
lineptr = line;
|
|
if (*lineptr == '/')
|
|
continue;
|
|
lineptr += strspn(lineptr, " \n\t");
|
|
len = strcspn(lineptr, " \n\t");
|
|
lineptr[len] = 0;
|
|
if (!strlen(lineptr))
|
|
continue;
|
|
if (lineptr[strlen(lineptr) - 1] == '-') { /* it's a prefix */
|
|
if (prefixcount == MAXPREFIXES) {
|
|
warnx("Memory for prefixes exceeded in line %d",
|
|
linenum);
|
|
continue;
|
|
}
|
|
lineptr[strlen(lineptr) - 1] = 0;
|
|
prefixtable[prefixcount].prefixname = dupstr(lineptr);
|
|
for (i = 0; i < prefixcount; i++)
|
|
if (!strcmp(prefixtable[i].prefixname, lineptr)) {
|
|
warnx(
|
|
"Redefinition of prefix '%s' on line %d ignored",
|
|
lineptr, linenum);
|
|
continue;
|
|
}
|
|
lineptr += len + 1;
|
|
if (!strlen(lineptr)) {
|
|
readerror(linenum);
|
|
continue;
|
|
}
|
|
lineptr += strspn(lineptr, " \n\t");
|
|
len = strcspn(lineptr, "\n\t");
|
|
lineptr[len] = 0;
|
|
prefixtable[prefixcount++].prefixval = dupstr(lineptr);
|
|
}
|
|
else { /* it's not a prefix */
|
|
if (unitcount == MAXUNITS) {
|
|
warnx("Memory for units exceeded in line %d",
|
|
linenum);
|
|
continue;
|
|
}
|
|
unittable[unitcount].uname = dupstr(lineptr);
|
|
for (i = 0; i < unitcount; i++)
|
|
if (!strcmp(unittable[i].uname, lineptr)) {
|
|
warnx(
|
|
"Redefinition of unit '%s' on line %d ignored",
|
|
lineptr, linenum);
|
|
continue;
|
|
}
|
|
lineptr += len + 1;
|
|
lineptr += strspn(lineptr, " \n\t");
|
|
if (!strlen(lineptr)) {
|
|
readerror(linenum);
|
|
continue;
|
|
}
|
|
len = strcspn(lineptr, "\n\t");
|
|
lineptr[len] = 0;
|
|
unittable[unitcount++].uval = dupstr(lineptr);
|
|
}
|
|
}
|
|
fclose(unitfile);
|
|
}
|
|
|
|
void
|
|
initializeunit(struct unittype * theunit)
|
|
{
|
|
theunit->factor = 1.0;
|
|
theunit->numerator[0] = theunit->denominator[0] = NULL;
|
|
}
|
|
|
|
|
|
int
|
|
addsubunit(char *product[], char *toadd)
|
|
{
|
|
char **ptr;
|
|
|
|
for (ptr = product; *ptr && *ptr != NULLUNIT; ptr++);
|
|
if (ptr >= product + MAXSUBUNITS) {
|
|
warnx("Memory overflow in unit reduction");
|
|
return 1;
|
|
}
|
|
if (!*ptr)
|
|
*(ptr + 1) = 0;
|
|
*ptr = dupstr(toadd);
|
|
return 0;
|
|
}
|
|
|
|
|
|
void
|
|
showunit(struct unittype * theunit)
|
|
{
|
|
char **ptr;
|
|
int printedslash;
|
|
int counter = 1;
|
|
|
|
printf("\t%.8g", theunit->factor);
|
|
for (ptr = theunit->numerator; *ptr; ptr++) {
|
|
if (ptr > theunit->numerator && **ptr &&
|
|
!strcmp(*ptr, *(ptr - 1)))
|
|
counter++;
|
|
else {
|
|
if (counter > 1)
|
|
printf("%s%d", powerstring, counter);
|
|
if (**ptr)
|
|
printf(" %s", *ptr);
|
|
counter = 1;
|
|
}
|
|
}
|
|
if (counter > 1)
|
|
printf("%s%d", powerstring, counter);
|
|
counter = 1;
|
|
printedslash = 0;
|
|
for (ptr = theunit->denominator; *ptr; ptr++) {
|
|
if (ptr > theunit->denominator && **ptr &&
|
|
!strcmp(*ptr, *(ptr - 1)))
|
|
counter++;
|
|
else {
|
|
if (counter > 1)
|
|
printf("%s%d", powerstring, counter);
|
|
if (**ptr) {
|
|
if (!printedslash)
|
|
printf(" /");
|
|
printedslash = 1;
|
|
printf(" %s", *ptr);
|
|
}
|
|
counter = 1;
|
|
}
|
|
}
|
|
if (counter > 1)
|
|
printf("%s%d", powerstring, counter);
|
|
printf("\n");
|
|
}
|
|
|
|
|
|
void
|
|
zeroerror()
|
|
{
|
|
warnx("Unit reduces to zero");
|
|
}
|
|
|
|
/*
|
|
Adds the specified string to the unit.
|
|
Flip is 0 for adding normally, 1 for adding reciprocal.
|
|
|
|
Returns 0 for successful addition, nonzero on error.
|
|
*/
|
|
|
|
int
|
|
addunit(struct unittype * theunit, char *toadd, int flip)
|
|
{
|
|
char *scratch, *savescr;
|
|
char *item;
|
|
char *divider, *slash;
|
|
int doingtop;
|
|
|
|
savescr = scratch = dupstr(toadd);
|
|
for (slash = scratch + 1; *slash; slash++)
|
|
if (*slash == '-' &&
|
|
(tolower(*(slash - 1)) != 'e' ||
|
|
!strchr(".0123456789", *(slash + 1))))
|
|
*slash = ' ';
|
|
slash = strchr(scratch, '/');
|
|
if (slash)
|
|
*slash = 0;
|
|
doingtop = 1;
|
|
do {
|
|
item = strtok(scratch, " *\t\n/");
|
|
while (item) {
|
|
if (strchr("0123456789.", *item)) { /* item is a number */
|
|
double num;
|
|
|
|
divider = strchr(item, '|');
|
|
if (divider) {
|
|
*divider = 0;
|
|
num = atof(item);
|
|
if (!num) {
|
|
zeroerror();
|
|
return 1;
|
|
}
|
|
if (doingtop ^ flip)
|
|
theunit->factor *= num;
|
|
else
|
|
theunit->factor /= num;
|
|
num = atof(divider + 1);
|
|
if (!num) {
|
|
zeroerror();
|
|
return 1;
|
|
}
|
|
if (doingtop ^ flip)
|
|
theunit->factor /= num;
|
|
else
|
|
theunit->factor *= num;
|
|
}
|
|
else {
|
|
num = atof(item);
|
|
if (!num) {
|
|
zeroerror();
|
|
return 1;
|
|
}
|
|
if (doingtop ^ flip)
|
|
theunit->factor *= num;
|
|
else
|
|
theunit->factor /= num;
|
|
|
|
}
|
|
}
|
|
else { /* item is not a number */
|
|
int repeat = 1;
|
|
|
|
if (strchr("23456789",
|
|
item[strlen(item) - 1])) {
|
|
repeat = item[strlen(item) - 1] - '0';
|
|
item[strlen(item) - 1] = 0;
|
|
}
|
|
for (; repeat; repeat--)
|
|
if (addsubunit(doingtop ^ flip ? theunit->numerator : theunit->denominator, item))
|
|
return 1;
|
|
}
|
|
item = strtok(NULL, " *\t/\n");
|
|
}
|
|
doingtop--;
|
|
if (slash) {
|
|
scratch = slash + 1;
|
|
}
|
|
else
|
|
doingtop--;
|
|
} while (doingtop >= 0);
|
|
free(savescr);
|
|
return 0;
|
|
}
|
|
|
|
|
|
int
|
|
compare(const void *item1, const void *item2)
|
|
{
|
|
return strcmp(*(char **) item1, *(char **) item2);
|
|
}
|
|
|
|
|
|
void
|
|
sortunit(struct unittype * theunit)
|
|
{
|
|
char **ptr;
|
|
int count;
|
|
|
|
for (count = 0, ptr = theunit->numerator; *ptr; ptr++, count++);
|
|
qsort(theunit->numerator, count, sizeof(char *), compare);
|
|
for (count = 0, ptr = theunit->denominator; *ptr; ptr++, count++);
|
|
qsort(theunit->denominator, count, sizeof(char *), compare);
|
|
}
|
|
|
|
|
|
void
|
|
cancelunit(struct unittype * theunit)
|
|
{
|
|
char **den, **num;
|
|
int comp;
|
|
|
|
den = theunit->denominator;
|
|
num = theunit->numerator;
|
|
|
|
while (*num && *den) {
|
|
comp = strcmp(*den, *num);
|
|
if (!comp) {
|
|
/* if (*den!=NULLUNIT) free(*den);
|
|
if (*num!=NULLUNIT) free(*num);*/
|
|
*den++ = NULLUNIT;
|
|
*num++ = NULLUNIT;
|
|
}
|
|
else if (comp < 0)
|
|
den++;
|
|
else
|
|
num++;
|
|
}
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
Looks up the definition for the specified unit.
|
|
Returns a pointer to the definition or a null pointer
|
|
if the specified unit does not appear in the units table.
|
|
*/
|
|
|
|
static char buffer[100]; /* buffer for lookupunit answers with
|
|
prefixes */
|
|
|
|
char *
|
|
lookupunit(char *unit)
|
|
{
|
|
int i;
|
|
char *copy;
|
|
|
|
for (i = 0; i < unitcount; i++) {
|
|
if (!strcmp(unittable[i].uname, unit))
|
|
return unittable[i].uval;
|
|
}
|
|
|
|
if (unit[strlen(unit) - 1] == '^') {
|
|
copy = dupstr(unit);
|
|
copy[strlen(copy) - 1] = 0;
|
|
for (i = 0; i < unitcount; i++) {
|
|
if (!strcmp(unittable[i].uname, copy)) {
|
|
strcpy(buffer, copy);
|
|
free(copy);
|
|
return buffer;
|
|
}
|
|
}
|
|
free(copy);
|
|
}
|
|
if (unit[strlen(unit) - 1] == 's') {
|
|
copy = dupstr(unit);
|
|
copy[strlen(copy) - 1] = 0;
|
|
for (i = 0; i < unitcount; i++) {
|
|
if (!strcmp(unittable[i].uname, copy)) {
|
|
strcpy(buffer, copy);
|
|
free(copy);
|
|
return buffer;
|
|
}
|
|
}
|
|
if (copy[strlen(copy) - 1] == 'e') {
|
|
copy[strlen(copy) - 1] = 0;
|
|
for (i = 0; i < unitcount; i++) {
|
|
if (!strcmp(unittable[i].uname, copy)) {
|
|
strcpy(buffer, copy);
|
|
free(copy);
|
|
return buffer;
|
|
}
|
|
}
|
|
}
|
|
free(copy);
|
|
}
|
|
for (i = 0; i < prefixcount; i++) {
|
|
if (!strncmp(prefixtable[i].prefixname, unit,
|
|
strlen(prefixtable[i].prefixname))) {
|
|
unit += strlen(prefixtable[i].prefixname);
|
|
if (!strlen(unit) || lookupunit(unit)) {
|
|
strcpy(buffer, prefixtable[i].prefixval);
|
|
strcat(buffer, " ");
|
|
strcat(buffer, unit);
|
|
return buffer;
|
|
}
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
reduces a product of symbolic units to primitive units.
|
|
The three low bits are used to return flags:
|
|
|
|
bit 0 (1) set on if reductions were performed without error.
|
|
bit 1 (2) set on if no reductions are performed.
|
|
bit 2 (4) set on if an unknown unit is discovered.
|
|
*/
|
|
|
|
|
|
#define ERROR 4
|
|
|
|
int
|
|
reduceproduct(struct unittype * theunit, int flip)
|
|
{
|
|
|
|
char *toadd;
|
|
char **product;
|
|
int didsomething = 2;
|
|
|
|
if (flip)
|
|
product = theunit->denominator;
|
|
else
|
|
product = theunit->numerator;
|
|
|
|
for (; *product; product++) {
|
|
|
|
for (;;) {
|
|
if (!strlen(*product))
|
|
break;
|
|
toadd = lookupunit(*product);
|
|
if (!toadd) {
|
|
printf("unknown unit '%s'\n", *product);
|
|
return ERROR;
|
|
}
|
|
if (strchr(toadd, PRIMITIVECHAR))
|
|
break;
|
|
didsomething = 1;
|
|
if (*product != NULLUNIT) {
|
|
free(*product);
|
|
*product = NULLUNIT;
|
|
}
|
|
if (addunit(theunit, toadd, flip))
|
|
return ERROR;
|
|
}
|
|
}
|
|
return didsomething;
|
|
}
|
|
|
|
|
|
/*
|
|
Reduces numerator and denominator of the specified unit.
|
|
Returns 0 on success, or 1 on unknown unit error.
|
|
*/
|
|
|
|
int
|
|
reduceunit(struct unittype * theunit)
|
|
{
|
|
int ret;
|
|
|
|
ret = 1;
|
|
while (ret & 1) {
|
|
ret = reduceproduct(theunit, 0) | reduceproduct(theunit, 1);
|
|
if (ret & 4)
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
|
|
int
|
|
compareproducts(char **one, char **two)
|
|
{
|
|
while (*one || *two) {
|
|
if (!*one && *two != NULLUNIT)
|
|
return 1;
|
|
if (!*two && *one != NULLUNIT)
|
|
return 1;
|
|
if (*one == NULLUNIT)
|
|
one++;
|
|
else if (*two == NULLUNIT)
|
|
two++;
|
|
else if (strcmp(*one, *two))
|
|
return 1;
|
|
else
|
|
one++, two++;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* Return zero if units are compatible, nonzero otherwise */
|
|
|
|
int
|
|
compareunits(struct unittype * first, struct unittype * second)
|
|
{
|
|
return
|
|
compareproducts(first->numerator, second->numerator) ||
|
|
compareproducts(first->denominator, second->denominator);
|
|
}
|
|
|
|
|
|
int
|
|
completereduce(struct unittype * unit)
|
|
{
|
|
if (reduceunit(unit))
|
|
return 1;
|
|
sortunit(unit);
|
|
cancelunit(unit);
|
|
return 0;
|
|
}
|
|
|
|
|
|
void
|
|
showanswer(struct unittype * have, struct unittype * want)
|
|
{
|
|
if (compareunits(have, want)) {
|
|
printf("conformability error\n");
|
|
showunit(have);
|
|
showunit(want);
|
|
}
|
|
else
|
|
printf("\t* %.8g\n\t/ %.8g\n", have->factor / want->factor,
|
|
want->factor / have->factor);
|
|
}
|
|
|
|
|
|
void
|
|
usage()
|
|
{
|
|
fprintf(stderr,
|
|
"\nunits [-f unitsfile] [-q] [-v] [from-unit to-unit]\n");
|
|
fprintf(stderr, "\n -f specify units file\n");
|
|
fprintf(stderr, " -q supress prompting (quiet)\n");
|
|
fprintf(stderr, " -v print version number\n");
|
|
exit(3);
|
|
}
|
|
|
|
|
|
int
|
|
main(int argc, char **argv)
|
|
{
|
|
|
|
struct unittype have, want;
|
|
char havestr[81], wantstr[81];
|
|
int optchar;
|
|
char *userfile = 0;
|
|
int quiet = 0;
|
|
|
|
while ((optchar = getopt(argc, argv, "vqf:")) != -1) {
|
|
switch (optchar) {
|
|
case 'f':
|
|
userfile = optarg;
|
|
break;
|
|
case 'q':
|
|
quiet = 1;
|
|
break;
|
|
case 'v':
|
|
fprintf(stderr, "\n units version %s Copyright (c) 1993 by Adrian Mariano\n",
|
|
VERSION);
|
|
fprintf(stderr, " This program may be freely distributed\n");
|
|
usage();
|
|
default:
|
|
usage();
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (optind != argc - 2 && optind != argc)
|
|
usage();
|
|
|
|
readunits(userfile);
|
|
|
|
if (optind == argc - 2) {
|
|
strcpy(havestr, argv[optind]);
|
|
strcpy(wantstr, argv[optind + 1]);
|
|
initializeunit(&have);
|
|
addunit(&have, havestr, 0);
|
|
completereduce(&have);
|
|
initializeunit(&want);
|
|
addunit(&want, wantstr, 0);
|
|
completereduce(&want);
|
|
showanswer(&have, &want);
|
|
}
|
|
else {
|
|
if (!quiet)
|
|
printf("%d units, %d prefixes\n\n", unitcount,
|
|
prefixcount);
|
|
for (;;) {
|
|
do {
|
|
initializeunit(&have);
|
|
if (!quiet)
|
|
printf("You have: ");
|
|
if (!fgets(havestr, 80, stdin)) {
|
|
if (!quiet);
|
|
putchar('\n');
|
|
exit(0);
|
|
}
|
|
} while (addunit(&have, havestr, 0) ||
|
|
completereduce(&have));
|
|
do {
|
|
initializeunit(&want);
|
|
if (!quiet)
|
|
printf("You want: ");
|
|
if (!fgets(wantstr, 80, stdin)) {
|
|
if (!quiet)
|
|
putchar('\n');
|
|
exit(0);
|
|
}
|
|
} while (addunit(&want, wantstr, 0) ||
|
|
completereduce(&want));
|
|
showanswer(&have, &want);
|
|
}
|
|
}
|
|
return (0);
|
|
}
|