src/common/portio.c

#ifndef lint
static const char       RCSid[] = "$Id: portio.c,v 2.21 2019/07/05 03:04:22 greg Exp $";
#endif
/*
 * Portable i/o for binary files
 *
 * External symbols declared in rtio.h
 */

#include "copyright.h"

#include "rtio.h"

#include <math.h>


void
putstr(                         /* write null-terminated string to fp */
        char  *s,
        FILE  *fp
)
{
        do
                putc(*s, fp);
        while (*s++);
}


void
putint(                         /* write a siz-byte integer to fp */
        long  i,
        int  siz,
        FILE  *fp
)
{
        siz <<= 3;
        while ((siz -= 8) > 0)
                putc((int)(i>>siz & 0xff), fp);
        putc((int)(i & 0xff), fp);
}


void
putflt(                         /* put out floating point number */
        double  f,
        FILE  *fp
)
{
        long  m;
        int  e;

        m = frexp(f, &e) * 0x7fffffff;
        if (e > 127) {                  /* overflow */
                m = m > 0 ? (long)0x7fffffff : -(long)0x7fffffff;
                e = 127;
        } else if (e < -128) {          /* underflow */
                m = 0;
                e = 0;
        }
        putint(m, 4, fp);
        putint(e, 1, fp);
}


int
putbinary(                      /* fwrite() replacement for small objects */
        const void *p,
        int elsiz,
        int nel,
        FILE *fp)
{
        const char      *s = (const char *)p;
        int             nbytes = elsiz*nel;

        if (nbytes > 128)
                return(fwrite(p, elsiz, nel, fp));
        
        while (nbytes-- > 0)
                if (putc(*s++, fp) == EOF)
                        return((elsiz*nel - nbytes)/elsiz);

        return(nel);
}


char *
getstr(                         /* get null-terminated string */
        char  *s,
        FILE  *fp
)
{
        char  *cp;
        int  c;

        cp = s;
        while ((c = getc(fp)) != EOF)
                if ((*cp++ = c) == '\0')
                        return(s);
                
        return(NULL);
}


long
getint(                         /* get a siz-byte integer */
        int  siz,
        FILE  *fp
)
{
        int  c;
        long  r;

        if ((c = getc(fp)) == EOF)
                return(EOF);
        r = 0x80&c ? -1<<8|c : c;               /* sign extend */
        while (--siz > 0) {
                if ((c = getc(fp)) == EOF)
                        return(EOF);
                r <<= 8;
                r |= c;
        }
        return(r);
}


double
getflt(                         /* get a floating point number */
        FILE  *fp
)
{
        long    l;
        double  d;

        l = getint(4, fp);
        if (l == EOF && feof(fp))       /* EOF? */
                return((double)EOF);
        if (l == 0) {
                getc(fp);               /* exactly zero -- ignore exponent */
                return(0.0);
        }
        d = (l + (l > 0 ? .5 : -.5)) * (1./0x7fffffff);
        return(ldexp(d, (int)getint(1, fp)));
}


int
getbinary(                      /* fread() replacement for small objects */
        void *p,
        int elsiz,
        int nel,
        FILE *fp)
{
        char    *s = (char *)p;
        int     nbytes = elsiz*nel;
        int     c;

        if (nbytes > 128)
                return(fread(p, elsiz, nel, fp));
        
        while (nbytes-- > 0) {
                if ((c = getc(fp)) == EOF)
                        return((elsiz*nel - nbytes)/elsiz);
                *s++ = c;
        }
        return(nel);
}
Revision:	2.22
Committed:	Mon Jul 15 21:27:25 2019 UTC (4 years, 9 months ago) by greg
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rad5R3
Changes since 2.21:	+6 -5 lines
Log Message:	Reduced size limit for fread() & fwrite() again and other minor changes
#	User	Rev	Content
1	greg	2.1	#ifndef lint
2	greg	2.22	static const char RCSid[] = "$Id: portio.c,v 2.21 2019/07/05 03:04:22 greg Exp $";
3	greg	2.1	#endif
4			/*
5			* Portable i/o for binary files
6	greg	2.6	*
7	greg	2.14	* External symbols declared in rtio.h
8	greg	2.6	*/
9
10	greg	2.7	#include "copyright.h"
11	greg	2.1
12	schorsch	2.8	#include "rtio.h"
13	greg	2.1
14	greg	2.9	#include <math.h>
15	greg	2.10
16	greg	2.3
17	greg	2.6	void
18	greg	2.15	putstr( /* write null-terminated string to fp */
19			char *s,
20			FILE *fp
21			)
22	greg	2.1	{
23			do
24			putc(*s, fp);
25			while (*s++);
26			}
27
28
29	greg	2.6	void
30	greg	2.15	putint( /* write a siz-byte integer to fp */
31			long i,
32			int siz,
33			FILE *fp
34			)
35	greg	2.1	{
36	greg	2.18	siz <<= 3;
37	greg	2.22	while ((siz -= 8) > 0)
38	greg	2.18	putc((int)(i>>siz & 0xff), fp);
39	greg	2.22	putc((int)(i & 0xff), fp);
40	greg	2.1	}
41
42
43	greg	2.6	void
44	greg	2.15	putflt( /* put out floating point number */
45			double f,
46			FILE *fp
47			)
48	greg	2.1	{
49	greg	2.13	long m;
50	greg	2.1	int e;
51
52	greg	2.13	m = frexp(f, &e) * 0x7fffffff;
53			if (e > 127) { /* overflow */
54			m = m > 0 ? (long)0x7fffffff : -(long)0x7fffffff;
55			e = 127;
56			} else if (e < -128) { /* underflow */
57			m = 0;
58			e = 0;
59			}
60			putint(m, 4, fp);
61	greg	2.22	putint(e, 1, fp);
62	greg	2.1	}
63
64
65	greg	2.16	int
66			putbinary( /* fwrite() replacement for small objects */
67	greg	2.19	const void *p,
68	greg	2.16	int elsiz,
69			int nel,
70			FILE *fp)
71			{
72	greg	2.19	const char s = (const char )p;
73			int nbytes = elsiz*nel;
74	greg	2.16
75	greg	2.22	if (nbytes > 128)
76	greg	2.19	return(fwrite(p, elsiz, nel, fp));
77	greg	2.16
78			while (nbytes-- > 0)
79	greg	2.21	if (putc(*s++, fp) == EOF)
80			return((elsiz*nel - nbytes)/elsiz);
81	greg	2.16
82			return(nel);
83			}
84
85
86	greg	2.1	char *
87	greg	2.15	getstr( /* get null-terminated string */
88			char *s,
89			FILE *fp
90			)
91	greg	2.1	{
92	greg	2.15	char *cp;
93			int c;
94	greg	2.1
95			cp = s;
96			while ((c = getc(fp)) != EOF)
97			if ((*cp++ = c) == '\0')
98			return(s);
99
100			return(NULL);
101			}
102
103
104			long
105	greg	2.15	getint( /* get a siz-byte integer */
106			int siz,
107			FILE *fp
108			)
109	greg	2.1	{
110	greg	2.15	int c;
111			long r;
112	greg	2.1
113			if ((c = getc(fp)) == EOF)
114			return(EOF);
115			r = 0x80&c ? -1<<8\|c : c; /* sign extend */
116			while (--siz > 0) {
117			if ((c = getc(fp)) == EOF)
118			return(EOF);
119			r <<= 8;
120			r \|= c;
121			}
122			return(r);
123			}
124
125
126			double
127	greg	2.15	getflt( /* get a floating point number */
128			FILE *fp
129			)
130	greg	2.1	{
131	greg	2.5	long l;
132	greg	2.2	double d;
133	greg	2.1
134	greg	2.5	l = getint(4, fp);
135	greg	2.15	if (l == EOF && feof(fp)) /* EOF? */
136			return((double)EOF);
137	greg	2.12	if (l == 0) {
138			getc(fp); /* exactly zero -- ignore exponent */
139			return(0.0);
140			}
141	greg	2.5	d = (l + (l > 0 ? .5 : -.5)) * (1./0x7fffffff);
142	greg	2.1	return(ldexp(d, (int)getint(1, fp)));
143			}
144	greg	2.16
145
146			int
147			getbinary( /* fread() replacement for small objects */
148	greg	2.19	void *p,
149	greg	2.16	int elsiz,
150			int nel,
151			FILE *fp)
152			{
153	greg	2.19	char s = (char )p;
154	greg	2.16	int nbytes = elsiz*nel;
155			int c;
156
157	greg	2.22	if (nbytes > 128)
158	greg	2.19	return(fread(p, elsiz, nel, fp));
159	greg	2.16
160			while (nbytes-- > 0) {
161			if ((c = getc(fp)) == EOF)
162			return((elsiz*nel - nbytes)/elsiz);
163			*s++ = c;
164			}
165			return(nel);
166			}