minix/commands/m4/serv.c
2005-04-21 14:53:53 +00:00

423 lines
11 KiB
C
Executable file

/*
* serv.c
* Facility: m4 macro processor
* by: oz
*/
#include "mdef.h"
#include "extr.h"
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);
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)
error("m4: null definition.");
if (strcmp(name, defn) == 0)
error("m4: recursive definition.");
if ((p = lookup(name)) == nil)
p = addent(name);
else if (p->defn != null)
free(p->defn);
if (!*defn)
p->defn = null;
else
p->defn = strsave(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)
error("m4: null definition");
if (strcmp(name, defn) == 0)
error("m4: recursive definition.");
p = addent(name);
if (!*defn)
p->defn = null;
else
p->defn = strsave(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 (strcmp(argv[2], argv[3]) == 0)
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)
error("m4: too many include files.");
if ((infile[ilevel+1] = fopen(ifile, "r")) != NULL) {
ilevel++;
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)
error("m4: cannot divert.");
}
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;
}