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)) { /* $3 */
int n = 0;
while (isdigit(*srcp->sp))
n = 10 * n + *srcp->sp++ - '0';
if (n > 0 && n <= MAXARGS)
pushsrc(String, argfp->argstk[n-1]);
goto loop;
}
break;
case File:
c = getc(curfile->fin);
if (c == EOF) {
if (curfile == infile)
ERROR "end of file inside .G1/.G2" FATAL;
if (curfile->fin != stdin) {
fclose(curfile->fin);
free(curfile->fname); /* assumes allocated */
}
curfile--;
printf(".lf %d %s\n", curfile->lineno, curfile->fname);
popsrc();
thru = 0; /* chicken out */
thrudef = 0;
if (untilstr) {
free(untilstr);
untilstr = 0;
}
goto loop;
}
if (c == '\n')
curfile->lineno++;
break;
}
return c;
}
int
input(void)
{
register int c = 0;
loop:
switch (srcp->type) {
case File:
c = getc(curfile->fin);
if (c == EOF) {
if (curfile == infile)
break;
if (curfile->fin != stdin) {
fclose(curfile->fin);
free(curfile->fname); /* assumes allocated */
}
curfile--;
printf(".lf %d %s\n", curfile->lineno, curfile->fname);
popsrc();
goto loop;
}
if (c == '\n')
curfile->lineno++;
break;
case Char:
if (pb >= pbuf) {
c = *pb--;
popsrc();
break;
} else { /* can't happen? */
popsrc();
goto loop;
}
case String:
c = *srcp->sp++;
if (c == '\0') {
popsrc();
goto loop;
} else {
if (*srcp->sp == '\0') /* empty, so pop */
popsrc();
break;
}
case Macro:
c = *srcp->sp++;
if (c == '\0') {
if (--argfp < args)
ERROR "argfp underflow" FATAL;
popsrc();
goto loop;
} else if (c == '$' && isdigit((unsigned char)*srcp->sp)) {
int n = 0;
while (isdigit((unsigned char)*srcp->sp))
n = 10 * n + *srcp->sp++ - '0';
if (n > 0 && n <= MAXARGS)
pushsrc(String, argfp->argstk[n-1]);
goto loop;
}
break;
case Free: /* free string */
free(srcp->sp);
popsrc();
goto loop;
}
if (ep >= ebuf + sizeof ebuf)
ep = ebuf;
*ep++ = c;
return c;
}
