4.4BSD/usr/src/usr.bin/m4/eval.c
/*
* Copyright (c) 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Ozan Yigit at York University.
*
* 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.
*/
#ifndef lint
static char sccsid[] = "@(#)eval.c 8.1 (Berkeley) 6/6/93";
#endif /* not lint */
/*
* eval.c
* Facility: m4 macro processor
* by: oz
*/
#include <sys/types.h>
#include <errno.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "mdef.h"
#include "stdd.h"
#include "extern.h"
#include "pathnames.h"
/*
* eval - evaluate built-in macros.
* argc - number of elements in argv.
* argv - element vector :
* argv[0] = definition of a user
* macro or nil if built-in.
* argv[1] = name of the macro or
* built-in.
* argv[2] = parameters to user-defined
* . macro or built-in.
* .
*
* Note that the minimum value for argc is 3. A call in the form
* of macro-or-builtin() will result in:
* argv[0] = nullstr
* argv[1] = macro-or-builtin
* argv[2] = nullstr
*/
void
eval(argv, argc, td)
register char *argv[];
register int argc;
register int td;
{
register int c, n;
static int sysval = 0;
#ifdef DEBUG
printf("argc = %d\n", argc);
for (n = 0; n < argc; n++)
printf("argv[%d] = %s\n", n, argv[n]);
#endif
/*
* if argc == 3 and argv[2] is null, then we
* have macro-or-builtin() type call. We adjust
* argc to avoid further checking..
*/
if (argc == 3 && !*(argv[2]))
argc--;
switch (td & ~STATIC) {
case DEFITYPE:
if (argc > 2)
dodefine(argv[2], (argc > 3) ? argv[3] : null);
break;
case PUSDTYPE:
if (argc > 2)
dopushdef(argv[2], (argc > 3) ? argv[3] : null);
break;
case DUMPTYPE:
dodump(argv, argc);
break;
case EXPRTYPE:
/*
* doexpr - evaluate arithmetic
* expression
*/
if (argc > 2)
pbnum(expr(argv[2]));
break;
case IFELTYPE:
if (argc > 4)
doifelse(argv, argc);
break;
case IFDFTYPE:
/*
* doifdef - select one of two
* alternatives based on the existence of
* another definition
*/
if (argc > 3) {
if (lookup(argv[2]) != nil)
pbstr(argv[3]);
else if (argc > 4)
pbstr(argv[4]);
}
break;
case LENGTYPE:
/*
* dolen - find the length of the
* argument
*/
if (argc > 2)
pbnum((argc > 2) ? strlen(argv[2]) : 0);
break;
case INCRTYPE:
/*
* doincr - increment the value of the
* argument
*/
if (argc > 2)
pbnum(atoi(argv[2]) + 1);
break;
case DECRTYPE:
/*
* dodecr - decrement the value of the
* argument
*/
if (argc > 2)
pbnum(atoi(argv[2]) - 1);
break;
case SYSCTYPE:
/*
* dosys - execute system command
*/
if (argc > 2)
sysval = system(argv[2]);
break;
case SYSVTYPE:
/*
* dosysval - return value of the last
* system call.
*
*/
pbnum(sysval);
break;
case INCLTYPE:
if (argc > 2)
if (!doincl(argv[2]))
oops("%s: %s", argv[2], strerror(errno));
break;
case SINCTYPE:
if (argc > 2)
(void) doincl(argv[2]);
break;
#ifdef EXTENDED
case PASTTYPE:
if (argc > 2)
if (!dopaste(argv[2]))
oops("%s: %s", argv[2], strerror(errno));
break;
case SPASTYPE:
if (argc > 2)
(void) dopaste(argv[2]);
break;
#endif
case CHNQTYPE:
dochq(argv, argc);
break;
case CHNCTYPE:
dochc(argv, argc);
break;
case SUBSTYPE:
/*
* dosub - select substring
*
*/
if (argc > 3)
dosub(argv, argc);
break;
case SHIFTYPE:
/*
* doshift - push back all arguments
* except the first one (i.e. skip
* argv[2])
*/
if (argc > 3) {
for (n = argc - 1; n > 3; n--) {
putback(rquote);
pbstr(argv[n]);
putback(lquote);
putback(',');
}
putback(rquote);
pbstr(argv[3]);
putback(lquote);
}
break;
case DIVRTYPE:
if (argc > 2 && (n = atoi(argv[2])) != 0)
dodiv(n);
else {
active = stdout;
oindex = 0;
}
break;
case UNDVTYPE:
doundiv(argv, argc);
break;
case DIVNTYPE:
/*
* dodivnum - return the number of
* current output diversion
*/
pbnum(oindex);
break;
case UNDFTYPE:
/*
* doundefine - undefine a previously
* defined macro(s) or m4 keyword(s).
*/
if (argc > 2)
for (n = 2; n < argc; n++)
remhash(argv[n], ALL);
break;
case POPDTYPE:
/*
* dopopdef - remove the topmost
* definitions of macro(s) or m4
* keyword(s).
*/
if (argc > 2)
for (n = 2; n < argc; n++)
remhash(argv[n], TOP);
break;
case MKTMTYPE:
/*
* dotemp - create a temporary file
*/
if (argc > 2)
pbstr(mktemp(argv[2]));
break;
case TRNLTYPE:
/*
* dotranslit - replace all characters in
* the source string that appears in the
* "from" string with the corresponding
* characters in the "to" string.
*/
if (argc > 3) {
char temp[MAXTOK];
if (argc > 4)
map(temp, argv[2], argv[3], argv[4]);
else
map(temp, argv[2], argv[3], null);
pbstr(temp);
}
else if (argc > 2)
pbstr(argv[2]);
break;
case INDXTYPE:
/*
* doindex - find the index of the second
* argument string in the first argument
* string. -1 if not present.
*/
pbnum((argc > 3) ? indx(argv[2], argv[3]) : -1);
break;
case ERRPTYPE:
/*
* doerrp - print the arguments to stderr
* file
*/
if (argc > 2) {
for (n = 2; n < argc; n++)
fprintf(stderr, "%s ", argv[n]);
fprintf(stderr, "\n");
}
break;
case DNLNTYPE:
/*
* dodnl - eat-up-to and including
* newline
*/
while ((c = gpbc()) != '\n' && c != EOF)
;
break;
case M4WRTYPE:
/*
* dom4wrap - set up for
* wrap-up/wind-down activity
*/
m4wraps = (argc > 2) ? xstrdup(argv[2]) : null;
break;
case EXITTYPE:
/*
* doexit - immediate exit from m4.
*/
exit((argc > 2) ? atoi(argv[2]) : 0);
break;
case DEFNTYPE:
if (argc > 2)
for (n = 2; n < argc; n++)
dodefn(argv[n]);
break;
default:
oops("%s: major botch.", "eval");
break;
}
}
char *dumpfmt = "`%s'\t`%s'\n"; /* format string for dumpdef */
/*
* expand - user-defined macro expansion
*/
void
expand(argv, argc)
register char *argv[];
register int argc;
{
register char *t;
register char *p;
register int n;
register int argno;
t = argv[0]; /* defn string as a whole */
p = t;
while (*p)
p++;
p--; /* last character of defn */
while (p > t) {
if (*(p - 1) != ARGFLAG)
putback(*p);
else {
switch (*p) {
case '#':
pbnum(argc - 2);
break;
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
if ((argno = *p - '0') < argc - 1)
pbstr(argv[argno + 1]);
break;
case '*':
for (n = argc - 1; n > 2; n--) {
pbstr(argv[n]);
putback(',');
}
pbstr(argv[2]);
break;
default:
putback(*p);
putback('$');
break;
}
p--;
}
p--;
}
if (p == t) /* do last character */
putback(*p);
}
/*
* dodefine - install definition in the table
*/
void
dodefine(name, defn)
register char *name;
register char *defn;
{
register ndptr p;
if (!*name)
oops("null definition.");
if (STREQ(name, defn))
oops("%s: recursive definition.", name);
if ((p = lookup(name)) == nil)
p = addent(name);
else if (p->defn != null)
free((char *) p->defn);
if (!*defn)
p->defn = null;
else
p->defn = xstrdup(defn);
p->type = MACRTYPE;
}
/*
* dodefn - push back a quoted definition of
* the given name.
*/
void
dodefn(name)
char *name;
{
register ndptr p;
if ((p = lookup(name)) != nil && p->defn != null) {
putback(rquote);
pbstr(p->defn);
putback(lquote);
}
}
/*
* dopushdef - install a definition in the hash table
* without removing a previous definition. Since
* each new entry is entered in *front* of the
* hash bucket, it hides a previous definition from
* lookup.
*/
void
dopushdef(name, defn)
register char *name;
register char *defn;
{
register ndptr p;
if (!*name)
oops("null definition");
if (STREQ(name, defn))
oops("%s: recursive definition.", name);
p = addent(name);
if (!*defn)
p->defn = null;
else
p->defn = xstrdup(defn);
p->type = MACRTYPE;
}
/*
* dodumpdef - dump the specified definitions in the hash
* table to stderr. If nothing is specified, the entire
* hash table is dumped.
*/
void
dodump(argv, argc)
register char *argv[];
register int argc;
{
register int n;
ndptr p;
if (argc > 2) {
for (n = 2; n < argc; n++)
if ((p = lookup(argv[n])) != nil)
fprintf(stderr, dumpfmt, p->name,
p->defn);
}
else {
for (n = 0; n < HASHSIZE; n++)
for (p = hashtab[n]; p != nil; p = p->nxtptr)
fprintf(stderr, dumpfmt, p->name,
p->defn);
}
}
/*
* doifelse - select one of two alternatives - loop.
*/
void
doifelse(argv, argc)
register char *argv[];
register int argc;
{
cycle {
if (STREQ(argv[2], argv[3]))
pbstr(argv[4]);
else if (argc == 6)
pbstr(argv[5]);
else if (argc > 6) {
argv += 3;
argc -= 3;
continue;
}
break;
}
}
/*
* doinclude - include a given file.
*/
int
doincl(ifile)
char *ifile;
{
if (ilevel + 1 == MAXINP)
oops("too many include files.");
if ((infile[ilevel + 1] = fopen(ifile, "r")) != NULL) {
ilevel++;
bbase[ilevel] = bufbase = bp;
return (1);
}
else
return (0);
}
#ifdef EXTENDED
/*
* dopaste - include a given file without any
* macro processing.
*/
int
dopaste(pfile)
char *pfile;
{
FILE *pf;
register int c;
if ((pf = fopen(pfile, "r")) != NULL) {
while ((c = getc(pf)) != EOF)
putc(c, active);
(void) fclose(pf);
return (1);
}
else
return (0);
}
#endif
/*
* dochq - change quote characters
*/
void
dochq(argv, argc)
register char *argv[];
register int argc;
{
if (argc > 2) {
if (*argv[2])
lquote = *argv[2];
if (argc > 3) {
if (*argv[3])
rquote = *argv[3];
}
else
rquote = lquote;
}
else {
lquote = LQUOTE;
rquote = RQUOTE;
}
}
/*
* dochc - change comment characters
*/
void
dochc(argv, argc)
register char *argv[];
register int argc;
{
if (argc > 2) {
if (*argv[2])
scommt = *argv[2];
if (argc > 3) {
if (*argv[3])
ecommt = *argv[3];
}
else
ecommt = ECOMMT;
}
else {
scommt = SCOMMT;
ecommt = ECOMMT;
}
}
/*
* dodivert - divert the output to a temporary file
*/
void
dodiv(n)
register int n;
{
if (n < 0 || n >= MAXOUT)
n = 0; /* bitbucket */
if (outfile[n] == NULL) {
m4temp[UNIQUE] = n + '0';
if ((outfile[n] = fopen(m4temp, "w")) == NULL)
oops("%s: cannot divert.", m4temp);
}
oindex = n;
active = outfile[n];
}
/*
* doundivert - undivert a specified output, or all
* other outputs, in numerical order.
*/
void
doundiv(argv, argc)
register char *argv[];
register int argc;
{
register int ind;
register int n;
if (argc > 2) {
for (ind = 2; ind < argc; ind++) {
n = atoi(argv[ind]);
if (n > 0 && n < MAXOUT && outfile[n] != NULL)
getdiv(n);
}
}
else
for (n = 1; n < MAXOUT; n++)
if (outfile[n] != NULL)
getdiv(n);
}
/*
* dosub - select substring
*/
void
dosub(argv, argc)
register char *argv[];
register int argc;
{
register char *ap, *fc, *k;
register int nc;
if (argc < 5)
nc = MAXTOK;
else
#ifdef EXPR
nc = expr(argv[4]);
#else
nc = atoi(argv[4]);
#endif
ap = argv[2]; /* target string */
#ifdef EXPR
fc = ap + expr(argv[3]); /* first char */
#else
fc = ap + atoi(argv[3]); /* first char */
#endif
if (fc >= ap && fc < ap + strlen(ap))
for (k = fc + min(nc, strlen(fc)) - 1; k >= fc; k--)
putback(*k);
}
/*
* map:
* map every character of s1 that is specified in from
* into s3 and replace in s. (source s1 remains untouched)
*
* This is a standard implementation of map(s,from,to) function of ICON
* language. Within mapvec, we replace every character of "from" with
* the corresponding character in "to". If "to" is shorter than "from",
* than the corresponding entries are null, which means that those
* characters dissapear altogether. Furthermore, imagine
* map(dest, "sourcestring", "srtin", "rn..*") type call. In this case,
* `s' maps to `r', `r' maps to `n' and `n' maps to `*'. Thus, `s'
* ultimately maps to `*'. In order to achieve this effect in an efficient
* manner (i.e. without multiple passes over the destination string), we
* loop over mapvec, starting with the initial source character. if the
* character value (dch) in this location is different than the source
* character (sch), sch becomes dch, once again to index into mapvec, until
* the character value stabilizes (i.e. sch = dch, in other words
* mapvec[n] == n). Even if the entry in the mapvec is null for an ordinary
* character, it will stabilize, since mapvec[0] == 0 at all times. At the
* end, we restore mapvec* back to normal where mapvec[n] == n for
* 0 <= n <= 127. This strategy, along with the restoration of mapvec, is
* about 5 times faster than any algorithm that makes multiple passes over
* destination string.
*/
void
map(dest, src, from, to)
register char *dest;
register char *src;
register char *from;
register char *to;
{
register char *tmp;
register char sch, dch;
static char mapvec[128] = {
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,
60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71,
72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83,
84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,
96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107,
108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119,
120, 121, 122, 123, 124, 125, 126, 127
};
if (*src) {
tmp = from;
/*
* create a mapping between "from" and
* "to"
*/
while (*from)
mapvec[*from++] = (*to) ? *to++ : (char) 0;
while (*src) {
sch = *src++;
dch = mapvec[sch];
while (dch != sch) {
sch = dch;
dch = mapvec[sch];
}
if (*dest = dch)
dest++;
}
/*
* restore all the changed characters
*/
while (*tmp) {
mapvec[*tmp] = *tmp;
tmp++;
}
}
*dest = (char) 0;
}