ref: cbe4b116989c0bfec49b9ae7a1d9a85ead6648ae
dir: /sys/src/cmd/pic/input.c/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
#include "pic.h"
#include "y.tab.h"
Infile infile[10];
Infile *curfile = infile;
#define MAXSRC 50
Src src[MAXSRC]; /* input source stack */
Src *srcp = src;
void do_thru(void);
int nextchar(void);
int getarg(char *);
void freedef(char *);
int baldelim(int, char *);
void pushsrc(int type, char *ptr) /* new input source */
{
if (++srcp >= src + MAXSRC)
ERROR "inputs nested too deep" FATAL;
srcp->type = type;
srcp->sp = ptr;
if (dbg > 1) {
printf("\n%3d ", srcp - src);
switch (srcp->type) {
case File:
printf("push file %s\n", ((Infile *)ptr)->fname);
break;
case Macro:
printf("push macro <%s>\n", ptr);
break;
case Char:
printf("push char <%c>\n", *ptr);
break;
case Thru:
printf("push thru\n");
break;
case String:
printf("push string <%s>\n", ptr);
break;
case Free:
printf("push free <%s>\n", ptr);
break;
default:
ERROR "pushed bad type %d", srcp->type FATAL;
}
}
}
void popsrc(void) /* restore an old one */
{
if (srcp <= src)
ERROR "too many inputs popped" FATAL;
if (dbg > 1) {
printf("%3d ", srcp - src);
switch (srcp->type) {
case File:
printf("pop file\n");
break;
case Macro:
printf("pop macro\n");
break;
case Char:
printf("pop char <%c>\n", *srcp->sp);
break;
case Thru:
printf("pop thru\n");
break;
case String:
printf("pop string\n");
break;
case Free:
printf("pop free\n");
break;
default:
ERROR "pop weird input %d", srcp->type FATAL;
}
}
srcp--;
}
void definition(char *s) /* collect definition for s and install */
/* definitions picked up lexically */
{
char *p;
struct symtab *stp;
p = delimstr("definition");
stp = lookup(s);
if (stp != NULL) { /* it's there before */
if (stp->s_type != DEFNAME) {
ERROR "%s used as variable and definition", s WARNING;
return;
}
free(stp->s_val.p);
stp->s_val.p = p;
} else {
YYSTYPE u;
u.p = p;
makevar(tostring(s), DEFNAME, u);
}
dprintf("installing %s as `%s'\n", s, p);
}
char *delimstr(char *s) /* get body of X ... X */
/* message if too big */
{
int c, delim, rdelim, n, deep;
static char *buf = NULL;
static int nbuf = 0;
char *p;
if (buf == NULL)
buf = grow(buf, "buf", nbuf += 1000, sizeof(buf[0]));
while ((delim = input()) == ' ' || delim == '\t' || delim == '\n')
;
rdelim = baldelim(delim, "{}"); /* could be "(){}[]`'" */
deep = 1;
for (p = buf; ; ) {
c = input();
if (c == rdelim)
if (--deep == 0)
break;
if (c == delim)
deep++;
if (p >= buf + nbuf) {
n = p - buf;
buf = grow(buf, "buf", nbuf += 1000, sizeof(buf[0]));
p = buf + n;
}
if (c == EOF)
ERROR "end of file in %s %c %.20s... %c", s, delim, buf, delim FATAL;
*p++ = c;
}
*p = '\0';
dprintf("delimstr %s %c <%s> %c\n", s, delim, buf, delim);
return tostring(buf);
}
baldelim(int c, char *s) /* replace c by balancing entry in s */
{
for ( ; *s; s += 2)
if (*s == c)
return s[1];
return c;
}
void undefine(char *s) /* undefine macro */
{
while (*s != ' ' && *s != '\t') /* skip "undef..." */
s++;
while (*s == ' ' || *s == '\t')
s++;
freedef(s);
}
Arg args[10]; /* argument frames */
Arg *argfp = args; /* frame pointer */
int argcnt; /* number of arguments seen so far */
void dodef(struct symtab *stp) /* collect args and switch input to defn */
{
int i, len;
char *p;
Arg *ap;
ap = argfp+1;
if (ap >= args+10)
ERROR "arguments too deep" FATAL;
argcnt = 0;
if (input() != '(')
ERROR "disaster in dodef" FATAL;
if (ap->argval == 0)
ap->argval = malloc(1000);
for (p = ap->argval; (len = getarg(p)) != -1; p += len) {
ap->argstk[argcnt++] = p;
if (input() == ')')
break;
}
for (i = argcnt; i < MAXARGS; i++)
ap->argstk[i] = "";
if (dbg)
for (i = 0; i < argcnt; i++)
printf("arg %d.%d = <%s>\n", ap-args, i+1, ap->argstk[i]);
argfp = ap;
pushsrc(Macro, stp->s_val.p);
}
getarg(char *p) /* pick up single argument, store in p, return length */
{
int n, c, npar;
n = npar = 0;
for ( ;; ) {
c = input();
if (c == EOF)
ERROR "end of file in getarg" FATAL;
if (npar == 0 && (c == ',' || c == ')'))
break;
if (c == '"') /* copy quoted stuff intact */
do {
*p++ = c;
n++;
} while ((c = input()) != '"' && c != EOF);
else if (c == '(')
npar++;
else if (c == ')')
npar--;
n++;
*p++ = c;
}
*p = 0;
unput(c);
return(n + 1);
}
#define PBSIZE 2000
char pbuf[PBSIZE]; /* pushback buffer */
char *pb = pbuf-1; /* next pushed back character */
char ebuf[200]; /* collect input here for error reporting */
char *ep = ebuf;
int begin = 0;
extern int thru;
extern struct symtab *thrudef;
extern char *untilstr;
input(void)
{
register int c;
if (thru && begin) {
do_thru();
begin = 0;
}
c = nextchar();
if (dbg > 1)
printf(" <%c>", c);
if (ep >= ebuf + sizeof ebuf)
ep = ebuf;
return *(unsigned char *)ep++ = c;
}
nextchar(void)
{
register int c;
loop:
switch (srcp->type) {
case Free: /* free string */
free(srcp->sp);
popsrc();
goto loop;
case Thru: /* end of pushed back line */
begin = 1;
popsrc();
c = '\n';
break;
case Char:
if (pb >= pbuf) {
c = *pb--;
popsrc();
break;
} else { /* can't happen? */
popsrc();
goto loop;
}
case String:
c = *srcp->sp++;
if (c == '\0') {
popsrc();
goto loop;
} else {
if (*srcp->sp == '\0') /* empty, so pop */
popsrc();
break;
}
case Macro:
c = *srcp->sp++;
if (c == '\0') {
if (--argfp < args)
ERROR "argfp underflow" FATAL;
popsrc();
goto loop;
} else if (c == '$' && isdigit(*srcp->sp)) {
int n = 0;
while (isdigit(*srcp->sp))
n = 10 * n + *srcp->sp++ - '0';
if (n > 0 && n <= MAXARGS)
pushsrc(String, argfp->argstk[n-1]);
goto loop;
}
break;
case File:
c = getc(curfile->fin);
if (c == EOF) {
if (curfile == infile)
ERROR "end of file inside .PS/.PE" FATAL;
if (curfile->fin != stdin) {
fclose(curfile->fin);
free(curfile->fname); /* assumes allocated */
}
curfile--;
printlf(curfile->lineno, curfile->fname);
popsrc();
thru = 0; /* chicken out */
thrudef = 0;
if (untilstr) {
free(untilstr);
untilstr = 0;
}
goto loop;
}
if (c == '\n')
curfile->lineno++;
break;
}
return c;
}
void do_thru(void) /* read one line, make into a macro expansion */
{
int c, i;
char *p;
Arg *ap;
ap = argfp+1;
if (ap >= args+10)
ERROR "arguments too deep" FATAL;
if (ap->argval == NULL)
ap->argval = malloc(1000);
p = ap->argval;
argcnt = 0;
c = nextchar();
if (thru == 0) { /* end of file was seen, so thru is done */
unput(c);
return;
}
for ( ; c != '\n' && c != EOF; ) {
if (c == ' ' || c == '\t') {
c = nextchar();
continue;
}
ap->argstk[argcnt++] = p;
if (c == '"') {
do {
*p++ = c;
if ((c = nextchar()) == '\\') {
*p++ = c;
*p++ = nextchar();
c = nextchar();
}
} while (c != '"' && c != '\n' && c != EOF);
*p++ = '"';
if (c == '"')
c = nextchar();
} else {
do {
*p++ = c;
} while ((c = nextchar())!=' ' && c!='\t' && c!='\n' && c!=',' && c!=EOF);
if (c == ',')
c = nextchar();
}
*p++ = '\0';
}
if (c == EOF)
ERROR "unexpected end of file in do_thru" FATAL;
if (argcnt == 0) { /* ignore blank line */
pushsrc(Thru, (char *) 0);
return;
}
for (i = argcnt; i < MAXARGS; i++)
ap->argstk[i] = "";
if (dbg)
for (i = 0; i < argcnt; i++)
printf("arg %d.%d = <%s>\n", ap-args, i+1, ap->argstk[i]);
if (strcmp(ap->argstk[0], ".PE") == 0) {
thru = 0;
thrudef = 0;
pushsrc(String, "\n.PE\n");
return;
}
if (untilstr && strcmp(ap->argstk[0], untilstr) == 0) {
thru = 0;
thrudef = 0;
free(untilstr);
untilstr = 0;
return;
}
pushsrc(Thru, (char *) 0);
dprintf("do_thru pushing back <%s>\n", thrudef->s_val.p);
argfp = ap;
pushsrc(Macro, thrudef->s_val.p);
}
unput(int c)
{
if (++pb >= pbuf + sizeof pbuf)
ERROR "pushback overflow" FATAL;
if (--ep < ebuf)
ep = ebuf + sizeof(ebuf) - 1;
*pb = c;
pushsrc(Char, pb);
return c;
}
void pbstr(char *s)
{
pushsrc(String, s);
}
double errcheck(double x, char *s)
{
extern int errno;
if (errno == EDOM) {
errno = 0;
ERROR "%s argument out of domain", s WARNING;
} else if (errno == ERANGE) {
errno = 0;
ERROR "%s result out of range", s WARNING;
}
return x;
}
char errbuf[200];
void eprint(void);
void yyerror(char *s)
{
extern char *cmdname;
int ern = errno; /* cause some libraries clobber it */
if (synerr)
return;
fflush(stdout);
fprintf(stderr, "%s: %s", cmdname, s);
if (ern > 0) {
errno = ern;
perror("???");
}
fprintf(stderr, " near %s:%d\n",
curfile->fname, curfile->lineno+1);
eprint();
synerr = 1;
errno = 0;
}
void eprint(void) /* try to print context around error */
{
char *p, *q;
p = ep - 1;
if (p > ebuf && *p == '\n')
p--;
for ( ; p >= ebuf && *p != '\n'; p--)
;
while (*p == '\n')
p++;
fprintf(stderr, " context is\n\t");
for (q=ep-1; q>=p && *q!=' ' && *q!='\t' && *q!='\n'; q--)
;
while (p < q)
putc(*p++, stderr);
fprintf(stderr, " >>> ");
while (p < ep)
putc(*p++, stderr);
fprintf(stderr, " <<< ");
while (pb >= pbuf)
putc(*pb--, stderr);
fgets(ebuf, sizeof ebuf, curfile->fin);
fprintf(stderr, "%s", ebuf);
pbstr("\n.PE\n"); /* safety first */
ep = ebuf;
}
void yywrap(void) {}
char *newfile = 0; /* filename for file copy */
char *untilstr = 0; /* string that terminates a thru */
int thru = 0; /* 1 if copying thru macro */
struct symtab *thrudef = 0; /* macro being used */
void copyfile(char *s) /* remember file to start reading from */
{
newfile = s;
}
void copydef(struct symtab *p) /* remember macro symtab ptr */
{
thrudef = p;
}
struct symtab *copythru(char *s) /* collect the macro name or body for thru */
{
struct symtab *p;
char *q, *addnewline(char *);
p = lookup(s);
if (p != NULL) {
if (p->s_type == DEFNAME) {
p->s_val.p = addnewline(p->s_val.p);
return p;
} else
ERROR "%s used as define and name", s FATAL;
}
/* have to collect the definition */
pbstr(s); /* first char is the delimiter */
q = delimstr("thru body");
s = "nameless";
p = lookup(s);
if (p != NULL) {
if (p->s_val.p)
free(p->s_val.p);
p->s_val.p = q;
} else {
YYSTYPE u;
u.p = q;
p = makevar(tostring(s), DEFNAME, u);
}
p->s_val.p = addnewline(p->s_val.p);
dprintf("installing %s as `%s'\n", s, p->s_val.p);
return p;
}
char *addnewline(char *p) /* add newline to end of p */
{
int n;
n = strlen(p);
if (p[n-1] != '\n') {
p = realloc(p, n+2);
p[n] = '\n';
p[n+1] = '\0';
}
return p;
}
void copyuntil(char *s) /* string that terminates a thru */
{
untilstr = s;
}
void copy(void) /* begin input from file, etc. */
{
FILE *fin;
if (newfile) {
if ((fin = fopen(newfile, "r")) == NULL)
ERROR "can't open file %s", newfile FATAL;
curfile++;
curfile->fin = fin;
curfile->fname = newfile;
curfile->lineno = 0;
printlf(1, curfile->fname);
pushsrc(File, curfile->fname);
newfile = 0;
}
if (thrudef) {
thru = 1;
begin = 1; /* wrong place */
}
}
char shellbuf[1000], *shellp;
void shell_init(void) /* set up to interpret a shell command */
{
sprintf(shellbuf, "rc -c '");
shellp = shellbuf + strlen(shellbuf);
}
void shell_text(char *s) /* add string to command being collected */
{
while (*shellp++ = *s++)
;
shellp--;
}
void shell_exec(void) /* do it */
{
*shellp++ = '\'';
*shellp = '\0';
system(shellbuf);
}