freebsd-skq/usr.bin/units/units.c
Edward Tomasz Napierala 840a09d240 Fix interaction between libedit initialization and Capsicum
in units(1). The most visible is the removal of libedit warnings
about being unable to open termcap database.

Reviewed by:	eadler@
MFC after:	1 month
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D3322
2015-08-08 10:38:37 +00:00

870 lines
19 KiB
C

/*
* 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.
*/
#ifndef lint
static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <histedit.h>
#include <getopt.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/capsicum.h>
#include "pathnames.h"
#ifndef UNITSFILE
#define UNITSFILE _PATH_UNITSLIB
#endif
#define MAXUNITS 1000
#define MAXPREFIXES 100
#define MAXSUBUNITS 500
#define PRIMITIVECHAR '!'
static const char *powerstring = "^";
static struct {
char *uname;
char *uval;
} unittable[MAXUNITS];
struct unittype {
char *numerator[MAXSUBUNITS];
char *denominator[MAXSUBUNITS];
double factor;
double offset;
int quantity;
};
static struct {
char *prefixname;
char *prefixval;
} prefixtable[MAXPREFIXES];
static char NULLUNIT[] = "";
#define SEPARATOR ":"
static int unitcount;
static int prefixcount;
static bool verbose = false;
static bool terse = false;
static const char * outputformat;
static const char * havestr;
static const char * wantstr;
static int addsubunit(char *product[], char *toadd);
static int addunit(struct unittype *theunit, const char *toadd, int flip, int quantity);
static void cancelunit(struct unittype * theunit);
static int compare(const void *item1, const void *item2);
static int compareproducts(char **one, char **two);
static int compareunits(struct unittype * first, struct unittype * second);
static int completereduce(struct unittype * unit);
static char *dupstr(const char *str);
static void initializeunit(struct unittype * theunit);
static char *lookupunit(const char *unit);
static void readunits(const char *userfile);
static int reduceproduct(struct unittype * theunit, int flip);
static int reduceunit(struct unittype * theunit);
static void showanswer(struct unittype * have, struct unittype * want);
static void showunit(struct unittype * theunit);
static void sortunit(struct unittype * theunit);
static void usage(void);
static void zeroerror(void);
static const char* promptstr = "";
static const char * prompt(EditLine *e __unused) {
return promptstr;
}
static char *
dupstr(const char *str)
{
char *ret;
ret = strdup(str);
if (!ret)
err(3, "dupstr");
return (ret);
}
static void
readunits(const char *userfile)
{
FILE *unitfile;
char line[512], *lineptr;
int len, linenum, i;
cap_rights_t unitfilerights;
unitcount = 0;
linenum = 0;
if (userfile) {
unitfile = fopen(userfile, "rt");
if (!unitfile)
errx(1, "unable to open units file '%s'", userfile);
}
else {
unitfile = fopen(UNITSFILE, "rt");
if (!unitfile) {
char *direc, *env;
char filename[1000];
env = getenv("PATH");
if (env) {
direc = strtok(env, SEPARATOR);
while (direc) {
snprintf(filename, sizeof(filename),
"%s/%s", direc, UNITSFILE);
unitfile = fopen(filename, "rt");
if (unitfile)
break;
direc = strtok(NULL, SEPARATOR);
}
}
if (!unitfile)
errx(1, "can't find units file '%s'", UNITSFILE);
}
}
cap_rights_init(&unitfilerights, CAP_READ, CAP_FSTAT);
if (cap_rights_limit(fileno(unitfile), &unitfilerights) < 0
&& errno != ENOSYS)
err(1, "cap_rights_limit() failed");
while (!feof(unitfile)) {
if (!fgets(line, sizeof(line), unitfile))
break;
linenum++;
lineptr = line;
if (*lineptr == '/' || *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;
lineptr += strspn(lineptr, " \n\t");
len = strcspn(lineptr, "\n\t");
if (len == 0) {
warnx("unexpected end of prefix on line %d",
linenum);
continue;
}
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)) {
warnx("unexpected end of unit on line %d",
linenum);
continue;
}
len = strcspn(lineptr, "\n\t");
lineptr[len] = 0;
unittable[unitcount++].uval = dupstr(lineptr);
}
}
fclose(unitfile);
}
static void
initializeunit(struct unittype * theunit)
{
theunit->numerator[0] = theunit->denominator[0] = NULL;
theunit->factor = 1.0;
theunit->offset = 0.0;
theunit->quantity = 0;
}
static 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) = NULL;
*ptr = dupstr(toadd);
return 0;
}
static void
showunit(struct unittype * theunit)
{
char **ptr;
int printedslash;
int counter = 1;
printf("%.8g", theunit->factor);
if (theunit->offset)
printf("&%.8g", theunit->offset);
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(void)
{
warnx("unit reduces to zero");
}
/*
Adds the specified string to the unit.
Flip is 0 for adding normally, 1 for adding reciprocal.
Quantity is 1 if this is a quantity to be converted rather than a pure unit.
Returns 0 for successful addition, nonzero on error.
*/
static int
addunit(struct unittype * theunit, const char *toadd, int flip, int quantity)
{
char *scratch, *savescr;
char *item;
char *divider, *slash, *offset;
int doingtop;
if (!strlen(toadd))
return 1;
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, offsetnum;
if (quantity)
theunit->quantity = 1;
offset = strchr(item, '&');
if (offset) {
*offset = 0;
offsetnum = atof(offset+1);
} else
offsetnum = 0.0;
divider = strchr(item, '|');
if (divider) {
*divider = 0;
num = atof(item);
if (!num) {
zeroerror();
return 1;
}
if (doingtop ^ flip) {
theunit->factor *= num;
theunit->offset *= num;
} else {
theunit->factor /= num;
theunit->offset /= num;
}
num = atof(divider + 1);
if (!num) {
zeroerror();
return 1;
}
if (doingtop ^ flip) {
theunit->factor /= num;
theunit->offset /= num;
} else {
theunit->factor *= num;
theunit->offset *= num;
}
}
else {
num = atof(item);
if (!num) {
zeroerror();
return 1;
}
if (doingtop ^ flip) {
theunit->factor *= num;
theunit->offset *= num;
} else {
theunit->factor /= num;
theunit->offset /= num;
}
}
if (doingtop ^ flip)
theunit->offset += offsetnum;
}
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;
}
static int
compare(const void *item1, const void *item2)
{
return strcmp(*(const char * const *)item1, *(const char * const *)item2);
}
static void
sortunit(struct unittype * theunit)
{
char **ptr;
unsigned 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(const 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)) {
strlcpy(buffer, copy, sizeof(buffer));
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)) {
strlcpy(buffer, copy, sizeof(buffer));
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)) {
strlcpy(buffer, copy, sizeof(buffer));
free(copy);
return buffer;
}
}
}
free(copy);
}
for (i = 0; i < prefixcount; i++) {
size_t len = strlen(prefixtable[i].prefixname);
if (!strncmp(prefixtable[i].prefixname, unit, len)) {
if (!strlen(unit + len) || lookupunit(unit + len)) {
snprintf(buffer, sizeof(buffer), "%s %s",
prefixtable[i].prefixval, unit + len);
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
static 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, 0))
return ERROR;
}
}
return didsomething;
}
/*
Reduces numerator and denominator of the specified unit.
Returns 0 on success, or 1 on unknown unit error.
*/
static 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;
}
static 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 */
static int
compareunits(struct unittype * first, struct unittype * second)
{
return
compareproducts(first->numerator, second->numerator) ||
compareproducts(first->denominator, second->denominator);
}
static int
completereduce(struct unittype * unit)
{
if (reduceunit(unit))
return 1;
sortunit(unit);
cancelunit(unit);
return 0;
}
static void
showanswer(struct unittype * have, struct unittype * want)
{
double ans;
char* oformat;
if (compareunits(have, want)) {
printf("conformability error\n");
if (verbose)
printf("\t%s = ", havestr);
else if (!terse)
printf("\t");
showunit(have);
if (!terse) {
if (verbose)
printf("\t%s = ", wantstr);
else
printf("\t");
showunit(want);
}
}
else if (have->offset != want->offset) {
if (want->quantity)
printf("WARNING: conversion of non-proportional quantities.\n");
if (have->quantity) {
asprintf(&oformat, "\t%s\n", outputformat);
printf(oformat,
(have->factor + have->offset-want->offset)/want->factor);
free(oformat);
}
else {
asprintf(&oformat, "\t (-> x*%sg %sg)\n\t (<- y*%sg %sg)\n",
outputformat, outputformat, outputformat, outputformat);
printf(oformat,
have->factor / want->factor,
(have->offset-want->offset)/want->factor,
want->factor / have->factor,
(want->offset - have->offset)/have->factor);
}
}
else {
ans = have->factor / want->factor;
if (verbose) {
printf("\t%s = ", havestr);
printf(outputformat, ans);
printf(" * %s", wantstr);
printf("\n");
}
else if (terse) {
printf(outputformat, ans);
printf("\n");
}
else {
printf("\t* ");
printf(outputformat, ans);
printf("\n");
}
if (verbose) {
printf("\t%s = (1 / ", havestr);
printf(outputformat, 1/ans);
printf(") * %s\n", wantstr);
}
else if (!terse) {
printf("\t/ ");
printf(outputformat, 1/ans);
printf("\n");
}
}
}
static void
usage(void)
{
fprintf(stderr,
"usage: units [-f unitsfile] [-UVq] [from-unit to-unit]\n");
exit(3);
}
static struct option longopts[] = {
{"help", no_argument, NULL, 'h'},
{"exponential", no_argument, NULL, 'e'},
{"file", required_argument, NULL, 'f'},
{"output-format", required_argument, NULL, 'o'},
{"quiet", no_argument, NULL, 'q'},
{"terse", no_argument, NULL, 't'},
{"unitsfile", no_argument, NULL, 'U'},
{"verbose", no_argument, NULL, 'v'},
{"version", no_argument, NULL, 'V'},
{ 0, 0, 0, 0 }
};
int
main(int argc, char **argv)
{
struct unittype have, want;
int optchar;
bool quiet;
bool readfile;
History *inhistory;
EditLine *el;
HistEvent ev;
int inputsz;
quiet = false;
readfile = false;
outputformat = "%.8g";
while ((optchar = getopt_long(argc, argv, "+ehf:oqtvUV", longopts, NULL)) != -1) {
switch (optchar) {
case 'e':
outputformat = "%6e";
break;
case 'f':
readfile = true;
if (strlen(optarg) == 0)
readunits(NULL);
else
readunits(optarg);
break;
case 'q':
quiet = true;
break;
case 't':
terse = true;
break;
case 'o':
outputformat = optarg;
break;
case 'v':
verbose = true;
break;
case 'V':
fprintf(stderr, "FreeBSD units\n");
/* FALLTHROUGH */
case 'U':
if (access(UNITSFILE, F_OK) == 0)
printf("%s\n", UNITSFILE);
else
printf("Units data file not found");
exit(0);
break;
case 'h':
/* FALLTHROUGH */
default:
usage();
}
}
if (!readfile)
readunits(NULL);
if (optind == argc - 2) {
if (cap_enter() < 0 && errno != ENOSYS)
err(1, "unable to enter capability mode");
havestr = argv[optind];
wantstr = argv[optind + 1];
initializeunit(&have);
addunit(&have, havestr, 0, 1);
completereduce(&have);
initializeunit(&want);
addunit(&want, wantstr, 0, 1);
completereduce(&want);
showanswer(&have, &want);
} else {
inhistory = history_init();
el = el_init(argv[0], stdin, stdout, stderr);
el_set(el, EL_PROMPT, &prompt);
el_set(el, EL_EDITOR, "emacs");
el_set(el, EL_SIGNAL, 1);
el_set(el, EL_HIST, history, inhistory);
el_source(el, NULL);
history(inhistory, &ev, H_SETSIZE, 800);
if (inhistory == 0)
err(1, "Could not initialize history");
if (cap_enter() < 0 && errno != ENOSYS)
err(1, "unable to enter capability mode");
if (!quiet)
printf("%d units, %d prefixes\n", unitcount,
prefixcount);
for (;;) {
do {
initializeunit(&have);
if (!quiet)
promptstr = "You have: ";
havestr = el_gets(el, &inputsz);
if (havestr == NULL)
exit(0);
if (inputsz > 0)
history(inhistory, &ev, H_ENTER,
havestr);
} while (addunit(&have, havestr, 0, 1) ||
completereduce(&have));
do {
initializeunit(&want);
if (!quiet)
promptstr = "You want: ";
wantstr = el_gets(el, &inputsz);
if (wantstr == NULL)
exit(0);
if (inputsz > 0)
history(inhistory, &ev, H_ENTER,
wantstr);
} while (addunit(&want, wantstr, 0, 1) ||
completereduce(&want));
showanswer(&have, &want);
}
history_end(inhistory);
el_end(el);
}
return (0);
}