#ifndef lint
static char *RCSid = "$Id: scanner.c,v 3.26 92/03/24 22:34:36 woo Exp Locker: woo $";
#endif
/* GNUPLOT - scanner.c */
/*
* Copyright (C) 1986, 1987, 1990, 1991, 1992 Thomas Williams, Colin Kelley
*
* Permission to use, copy, and distribute this software and its
* documentation for any purpose with or without fee is hereby granted,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation.
*
* Permission to modify the software is granted, but not the right to
* distribute the modified code. Modifications are to be distributed
* as patches to released version.
*
* This software is provided "as is" without express or implied warranty.
*
*
* AUTHORS
*
* Original Software:
* Thomas Williams, Colin Kelley.
*
* Gnuplot 2.0 additions:
* Russell Lang, Dave Kotz, John Campbell.
*
* Gnuplot 3.0 additions:
* Gershon Elber and many others.
*
* Send your comments or suggestions to
* info-gnuplot@ames.arc.nasa.gov.
* This is a mailing list; to join it send a note to
* info-gnuplot-request@ames.arc.nasa.gov.
* Send bug reports to
* bug-gnuplot@ames.arc.nasa.gov.
*/
#include <stdio.h>
#include <ctype.h>
#include "plot.h"
#ifdef AMIGA_AC_5
#define O_RDONLY 0
int open(const char * _name, int _mode, ...);
int close(int);
#endif
#ifdef vms
#include stdio
#include descrip
#include errno
#define MAILBOX "PLOT$MAILBOX"
#define pclose(f) fclose(f)
#endif /* vms */
#define isident(c) (isalnum(c) || (c) == '_')
#ifndef STDOUT
#define STDOUT 1
#endif
#define LBRACE '{'
#define RBRACE '}'
#define APPEND_TOKEN {token[t_num].length++; current++;}
#define SCAN_IDENTIFIER while (isident(expression[current + 1]))\
APPEND_TOKEN
extern struct lexical_unit token[MAX_TOKENS];
static int t_num; /* number of token I'm working on */
char *strcat(), *strcpy(), *strncpy();
/*
* scanner() breaks expression[] into lexical units, storing them in token[].
* The total number of tokens found is returned as the function value.
* Scanning will stop when '\0' is found in expression[], or when token[]
* is full.
*
* Scanning is performed by following rules:
*
* Current char token should contain
* ------------- -----------------------
* 1. alpha,_ all following alpha-numerics
* 2. digit 0 or more following digits, 0 or 1 decimal point,
* 0 or more digits, 0 or 1 'e' or 'E',
* 0 or more digits.
* 3. ^,+,-,/ only current char
* %,~,(,)
* [,],;,:,
* ?,comma
* 4. &,|,=,* current char; also next if next is same
* 5. !,<,> current char; also next if next is =
* 6. ", ' all chars up until matching quote
* 7. # this token cuts off scanning of the line (DFK).
*
* white space between tokens is ignored
*/
scanner(expression)
char expression[];
{
register int current; /* index of current char in expression[] */
register int quote;
char brace;
for (current = t_num = 0;
t_num < MAX_TOKENS && expression[current] != '\0';
current++) {
again:
if (isspace(expression[current]))
continue; /* skip the whitespace */
token[t_num].start_index = current;
token[t_num].length = 1;
token[t_num].is_token = TRUE; /* to start with...*/
if (expression[current] == '`') {
substitute(&expression[current],MAX_LINE_LEN - current);
goto again;
}
/* allow _ to be the first character of an identifier */
if (isalpha(expression[current]) || expression[current] == '_') {
SCAN_IDENTIFIER;
} else if (isdigit(expression[current]) || expression[current] == '.'){
token[t_num].is_token = FALSE;
token[t_num].length = get_num(&expression[current]);
current += (token[t_num].length - 1);
} else if (expression[current] == LBRACE) {
token[t_num].is_token = FALSE;
token[t_num].l_val.type = CMPLX;
if ((sscanf(&expression[++current],"%lf , %lf %c",
&token[t_num].l_val.v.cmplx_val.real,
&token[t_num].l_val.v.cmplx_val.imag,
&brace) != 3) || (brace != RBRACE))
int_error("invalid complex constant",t_num);
token[t_num].length += 2;
while (expression[++current] != RBRACE) {
token[t_num].length++;
if (expression[current] == '\0') /* { for vi % */
int_error("no matching '}'", t_num);
}
} else if (expression[current] == '\'' || expression[current] == '\"'){
token[t_num].length++;
quote = expression[current];
while (expression[++current] != quote) {
if (!expression[current]) {
expression[current] = quote;
expression[current+1] = '\0';
break;
} else
token[t_num].length++;
}
} else switch (expression[current]) {
case '#': /* DFK: add comments to gnuplot */
goto endline; /* ignore the rest of the line */
case '^':
case '+':
case '-':
case '/':
case '%':
case '~':
case '(':
case ')':
case '[':
case ']':
case ';':
case ':':
case '?':
case ',':
break;
case '&':
case '|':
case '=':
case '*':
if (expression[current] == expression[current + 1])
APPEND_TOKEN;
break;
case '!':
case '<':
case '>':
if (expression[current + 1] == '=')
APPEND_TOKEN;
break;
default:
int_error("invalid character",t_num);
}
++t_num; /* next token if not white space */
}
endline: /* comments jump here to ignore line */
/* Now kludge an extra token which points to '\0' at end of expression[].
This is useful so printerror() looks nice even if we've fallen off the
line. */
token[t_num].start_index = current;
token[t_num].length = 0;
return(t_num);
}
get_num(str)
char str[];
{
double atof();
register int count = 0;
long atol();
register long lval;
token[t_num].is_token = FALSE;
token[t_num].l_val.type = INT; /* assume unless . or E found */
while (isdigit(str[count]))
count++;
if (str[count] == '.') {
token[t_num].l_val.type = CMPLX;
while (isdigit(str[++count])) /* swallow up digits until non-digit */
;
/* now str[count] is other than a digit */
}
if (str[count] == 'e' || str[count] == 'E') {
token[t_num].l_val.type = CMPLX;
/* modified if statement to allow + sign in exponent
rjl 26 July 1988 */
count++;
if (str[count] == '-' || str[count] == '+')
count++;
if (!isdigit(str[count])) {
token[t_num].start_index += count;
int_error("expecting exponent",t_num);
}
while (isdigit(str[++count]))
;
}
if (token[t_num].l_val.type == INT) {
lval = atol(str);
if ((token[t_num].l_val.v.int_val = lval) != lval)
int_error("integer overflow; change to floating point",t_num);
} else {
token[t_num].l_val.v.cmplx_val.imag = 0.0;
token[t_num].l_val.v.cmplx_val.real = atof(str);
}
return(count);
}
#ifdef MSDOS
#ifdef __ZTC__
substitute(char *str,int max)
#else
substitute()
#endif
{
int_error("substitution not supported by MS-DOS!",t_num);
}
#else /* MSDOS */
#ifdef AMIGA_LC_5_1
substitute()
{
int_error("substitution not supported by AmigaDOS!",t_num);
}
#else /* AMIGA_LC_5_1 */
substitute(str,max) /* substitute output from ` ` */
char *str;
int max;
{
register char *last;
register int i,c;
register FILE *f;
#ifdef AMIGA_AC_5
int fd;
#else
FILE *popen();
#endif
static char pgm[MAX_LINE_LEN+1],output[MAX_LINE_LEN+1];
#ifdef vms
int chan;
static $DESCRIPTOR(pgmdsc,pgm);
static $DESCRIPTOR(lognamedsc,MAILBOX);
#endif /* vms */
i = 0;
last = str;
while (*(++last) != '`') {
if (*last == '\0')
int_error("unmatched `",t_num);
pgm[i++] = *last;
}
pgm[i] = '\0'; /* end with null */
max -= strlen(last); /* max is now the max length of output sub. */
#ifdef vms
pgmdsc.dsc$w_length = i;
if (!((vaxc$errno = sys$crembx(0,&chan,0,0,0,0,&lognamedsc)) & 1))
os_error("sys$crembx failed",NO_CARET);
if (!((vaxc$errno = lib$spawn(&pgmdsc,0,&lognamedsc,&1)) & 1))
os_error("lib$spawn failed",NO_CARET);
if ((f = fopen(MAILBOX,"r")) == NULL)
os_error("mailbox open failed",NO_CARET);
#else /* vms */
#ifdef AMIGA_AC_5
if ((fd = open(pgm,"O_RDONLY")) == -1)
#else
if ((f = popen(pgm,"r")) == NULL)
#endif
os_error("popen failed",NO_CARET);
#endif /* vms */
i = 0;
while ((c = getc(f)) != EOF) {
output[i++] = ((c == '\n') ? ' ' : c); /* newlines become blanks*/
if (i == max) {
#ifdef AMIGA_AC_5
(void) close(fd);
#else
(void) pclose(f);
#endif
int_error("substitution overflow", t_num);
}
}
#ifdef AMIGA_AC_5
(void) close(fd);
#else
(void) pclose(f);
#endif
if (i + strlen(last) > max)
int_error("substitution overflowed rest of line", t_num);
(void) strncpy(output+i,last+1,MAX_LINE_LEN-i);
/* tack on rest of line to output */
(void) strcpy(str,output); /* now replace ` ` with output */
screen_ok = FALSE;
}
#endif /* AMIGA_LC_5_1 */
#endif /* MS-DOS */