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    Length: 4197 (0x1065)
    Types: TextFile
    Names: »fileio.c«

└─⟦a0efdde77⟧ Bits:30001252 EUUGD11 Tape, 1987 Spring Conference Helsinki
    └─ ⟦this⟧ »EUUGD11/euug-87hel/sec1/micrognu/sys/vms/fileio.c« 

TextFile

/*
 * Name:	MicroEMACS
 * Version:	30
 *		VAX/VMS file I/O.
 * Last edit:	05-Feb-86
 * By:		rex::conroy
 *		decvax!decwrl!dec-rhea!dec-rex!conroy
 *
 * Read and write ASCII files. All
 * of the low level file I/O knowledge is here.
 * VAX/VMS.
 * Pretty much vanilla standard I/O, using
 * the (traditional) funny open.
 */
#include	"def.h"

static	FILE	*ffp;

/*
 * Open a file for reading.
 */
ffropen(fn)
char	*fn;
{
	if ((ffp=fopen(fn, "r")) == NULL)
		return (FIOFNF);
	return (FIOSUC);
}

/*
 * Open a file for writing.
 * Return TRUE if all is well, and
 * FALSE on error (cannot create).
 */
ffwopen(fn)
char	*fn;
{
	register int	fd;

	if ((fd=creat(fn, 0, "rfm=var", "rat=cr")) < 0
	|| (ffp=fdopen(fd, "w")) == NULL) {
		ewprintf("Cannot open file for writing");
		return (FIOERR);
	}
	return (FIOSUC);
}

/*
 * Close a file.
 * Should look at the status.
 */
ffclose()
{
	fclose(ffp);
	return (FIOSUC);
}

/*
 * Write a line to the already
 * opened file. The "buf" points to the
 * buffer, and the "nbuf" is its length, less
 * the free newline. Return the status.
 * Check only at the newline.
 */
ffputline(buf, nbuf)
register char	buf[];
{
	register int	i;

	for (i=0; i<nbuf; ++i)
		putc(buf[i]&0xFF, ffp);
	putc('\n', ffp);
	if (ferror(ffp) != FALSE) {
		ewprintf("Write I/O error");
		return (FIOERR);
	}
	return (FIOSUC);
}

/*
 * Read a line from a file, and store the bytes
 * in the supplied buffer. Stop on end of file or end of
 * line. Don't get upset by files that don't have an end of
 * line on the last line; this seem to be common on CP/M-86 and
 * MS-DOS (the suspected culprit is VAX/VMS kermit, but this
 * has not been confirmed. If this is sufficiently researched
 * it may be possible to pull this kludge). Delete any CR
 * followed by an LF. This is mainly for runoff documents,
 * both on VMS and on Ultrix (they get copied over from
 * VMS systems with DECnet).
 * (17-Jul-1986 MPK) strip NULs too.
 */
ffgetline(buf, nbuf)
register char	buf[];
{
	register int	c;
	register int	i;

	i = 0;
	for (;;) {
		c = getc(ffp);
		if (c == '\r') {		/* Delete any non-stray	*/
			c = getc(ffp);		/* carriage returns.	*/
			if (c != '\n') {
				if (i >= nbuf-1) {
					ewprintf("File has long line");
					return (FIOERR);
				}
				buf[i++] = '\r';
			}
		}
		if (c==EOF || c=='\n')		/* End of line.		*/
			break;
		if (c == '\0')			/* strip NULs		*/
			continue;
		if (i >= nbuf-1) {
			ewprintf("File has long line");
			return (FIOERR);
		}
		buf[i++] = c;
	}
	if (c == EOF) {				/* End of file.		*/
		if (ferror(ffp) != FALSE) {
			ewprintf("File read error");
			return (FIOERR);
		}
		if (i == 0)			/* Don't get upset if	*/
			return (FIOEOF);	/* no newline at EOF.	*/
	}
	buf[i] = 0;
	return (FIOSUC);
}

/*
 * VMS has version numbers, so there is
 * no need for MicroEMACS to bother making its own
 * flavour of backup copy. Return TRUE so the
 * caller doesn't quit.
 */
fbackupfile(fname)
char	*fname;
{
	return (TRUE);
}

/*
 * The string "fn" is a file name.
 * Perform any required case adjustments. All sustems
 * we deal with so far have case insensitive file systems.
 * We zap everything to lower case. The problem we are trying
 * to solve is getting 2 buffers holding the same file if
 * you visit one of them with the "caps lock" key down.
 * On UNIX file names are dual case, so we leave
 * everything alone.
 */
adjustcase(fn)
register char	*fn;
{
	register int	c;

	while ((c = *fn) != 0) {
		if (c>='A' && c<='Z')
			*fn = c + 'a' - 'A';
		++fn;
	}
}

#ifndef	MICRO
#include <file.h>
/*
 * Find the user's startup file, and return its name.
 * Use the VAX C getenv() function, which returns the VMS
 * directory spec for the user's home directory.
 * Check for ${HOME}.emacs, then for ${HOME}.mg, then give up.
 */
char *
startupfile() {
	register char	*file;
	static char	home[NFILEN];
	char		*getenv();

	if ((file = getenv("HOME")) == NULL) return NULL;
	if (strlen(file)+7 >= NFILEN - 1) return NULL;
	(VOID) strcpy(home, file);
	file = &(home[strlen(home)]);

	(VOID) strcpy(file, ".mg");
	if (access(home, O_RDONLY ) == 0) return home;

	(VOID) strcpy(file, ".emacs");
	if (access(home, O_RDONLY) == 0) return home;

	return NULL;
}
#endif