src/common/fgetword.c

#ifndef lint
static const char       RCSid[] = "$Id: fgetword.c,v 2.8 2017/08/10 19:10:44 greg Exp $";
#endif
/*
 * Read white space separated words from stream
 *
 *  External symbols declared in rtio.h
 */

#include "copyright.h"

#include  "rtio.h"

#include  <ctype.h>


#define isquote(c)      (((c) == '"') | ((c) == '\''))


char *
fgetword(                       /* get (quoted) word up to n-1 characters */
        char  *s,
        int  n,
        FILE  *fp
)
{
        int  quote = '\0';
        char  *cp;
        int  c;
                                        /* sanity checks */
        if ((s == NULL) | (n < 2))
                return(NULL);
                                        /* skip initial white space */
        do
                c = getc(fp);
        while (isspace(c));
                                        /* check for quote */
        if (isquote(c)) {
                quote = c;
                c = getc(fp);
        }
        cp = s;                         /* get actual word */
        while (c != EOF) {
                if (c == quote)         /* end quote? */
                        quote = '\0';
                else if (!quote && isquote(c))
                        quote = c;      /* started new quote */
                else {
                        if (!quote && isspace(c))
                                break;  /* end of word */
                        if (--n <= 0)
                                break;  /* hit length limit */
                        *cp++ = c;
                }
                c = getc(fp);           /* get next character */
        }
        *cp = '\0';
        if ((c == EOF) & (cp == s))     /* hit end-of-file? */
                return(NULL);
        return(s);
}
Revision:	2.9
Committed:	Fri Feb 10 04:32:19 2023 UTC (2 years, 8 months ago) by greg
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rad5R4, rad6R0, HEAD
Changes since 2.8:	+21 -14 lines
Log Message:	perf: Eliminated call to ungetc() for better performance
#	User	Rev	Content
1	greg	1.1	#ifndef lint
2	greg	2.9	static const char RCSid[] = "$Id: fgetword.c,v 2.8 2017/08/10 19:10:44 greg Exp $";
3	greg	1.1	#endif
4			/*
5			* Read white space separated words from stream
6	greg	2.2	*
7	greg	2.4	* External symbols declared in rtio.h
8	greg	2.2	*/
9
10	greg	2.3	#include "copyright.h"
11	greg	1.1
12	greg	2.4	#include "rtio.h"
13	greg	1.1
14			#include <ctype.h>
15
16
17	greg	2.9	#define isquote(c) (((c) == '"') \| ((c) == '\''))
18
19
20	greg	1.1	char *
21	greg	2.6	fgetword( /* get (quoted) word up to n-1 characters */
22			char *s,
23			int n,
24	greg	2.7	FILE *fp
25	greg	2.6	)
26	greg	1.1	{
27	greg	2.2	int quote = '\0';
28	greg	2.7	char *cp;
29			int c;
30	greg	2.6	/* sanity checks */
31	greg	2.7	if ((s == NULL) \| (n < 2))
32	greg	2.6	return(NULL);
33	greg	1.1	/* skip initial white space */
34			do
35			c = getc(fp);
36			while (isspace(c));
37	greg	2.2	/* check for quote */
38	greg	2.9	if (isquote(c)) {
39	greg	2.2	quote = c;
40			c = getc(fp);
41			}
42	greg	2.9	cp = s; /* get actual word */
43			while (c != EOF) {
44			if (c == quote) /* end quote? */
45			quote = '\0';
46			else if (!quote && isquote(c))
47			quote = c; /* started new quote */
48			else {
49			if (!quote && isspace(c))
50			break; /* end of word */
51			if (--n <= 0)
52			break; /* hit length limit */
53			*cp++ = c;
54			}
55			c = getc(fp); /* get next character */
56	greg	2.7	}
57	greg	1.1	*cp = '\0';
58	greg	2.9	if ((c == EOF) & (cp == s)) /* hit end-of-file? */
59			return(NULL);
60	greg	1.1	return(s);
61			}