pass.c

这是一个同样来自贝尔实验室的和UNIX有着渊源的操作系统, 其简洁的设计和实现易于我们学习和理解

/* $Source: /u/mark/src/pax/RCS/pass.c,v $
 *
 * $Revision: 1.3 $
 *
 * pass.c - handle the pass option of cpio
 *
 * DESCRIPTION
 *
 *	These functions implement the pass options in PAX.  The pass option
 *	copies files from one directory hierarchy to another.
 * 
 * AUTHOR
 *
 *	Mark H. Colburn, NAPS International ([e-mail])
 *
 * Sponsored by The USENIX Association for public distribution. 
 *
 * Copyright (c) 1989 Mark H. Colburn.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice is duplicated in all such 
 * forms and that any documentation, advertising materials, and other 
 * materials related to such distribution and use acknowledge that the 
 * software was developed * by Mark H. Colburn and sponsored by The 
 * USENIX Association. 
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * $Log:	pass.c,v $
 * Revision 1.3  89/02/12  10:29:51  mark
 * Fixed misspelling of Replstr
 * 
 * Revision 1.2  89/02/12  10:05:09  mark
 * 1.2 release fixes
 * 
 * Revision 1.1  88/12/23  18:02:20  mark
 * Initial revision
 * 
 */

#ifndef lint
static char *ident = "$Id: pass.c,v 1.3 89/02/12 10:29:51 mark Exp $";
static char *copyright = "Copyright (c) 1989 Mark H. Colburn.\nAll rights reserved.\n";
#endif /* ! lint */


/* Headers */

#include "pax.h"


/* pass - copy within the filesystem
 *
 * DESCRIPTION
 *
 *	Pass copies the named files from the current directory hierarchy to
 *	the directory pointed to by dirname.
 *
 * PARAMETERS
 *
 *	char	*dirname	- name of directory to copy named files to.
 *
 */

#ifdef __STDC__
    
int pass(char *dirname)

#else
    
int pass(dirname)
char	*dirname;

#endif
{
    char            name[PATH_MAX + 1];
    int             fd;
    Stat            sb;

    while (name_next(name, &sb) >= 0 && (fd = openin(name, &sb)) >= 0) {

	if (rplhead != (Replstr *)NULL) {
	    rpl_name(name);
	}
	if (get_disposition("pass", name) || get_newname(name, sizeof(name))) {
	    /* skip file... */
	    if (fd) {
		close(fd);
	    }
	    continue;
	} 

	if (passitem(name, &sb, fd, dirname)) {
	    close(fd);
	}
	if (f_verbose) {
	    fprintf(stderr, "%s/%s\n", dirname, name);
	}
    }
}


/* passitem - copy one file
 *
 * DESCRIPTION
 *
 *	Passitem copies a specific file to the named directory
 *
 * PARAMETERS
 *
 *	char   *from	- the name of the file to open
 *	Stat   *asb	- the stat block associated with the file to copy
 *	int	ifd	- the input file descriptor for the file to copy
 *	char   *dir	- the directory to copy it to
 *
 * RETURNS
 *
 * 	Returns given input file descriptor or -1 if an error occurs.
 *
 * ERRORS
 */

#ifdef __STDC__

int passitem(char *from, Stat *asb, int ifd, char *dir)

#else
    
int passitem(from, asb, ifd, dir)
char           *from;
Stat           *asb;
int             ifd;
char           *dir;

#endif
{
    int             ofd;
    time_t          tstamp[2];
    char            to[PATH_MAX + 1];

    if (nameopt(strcat(strcat(strcpy(to, dir), "/"), from)) < 0) {
	return (-1);
    }
    if (asb->sb_nlink > 1) {
	linkto(to, asb);
    }
    if (f_link && islink(from, asb) == (Link *)NULL) {
	linkto(from, asb);
    }
    if ((ofd = openout(to, asb, islink(to, asb), 1)) < 0) {
	return (-1);
    }
    if (ofd > 0) {
	passdata(from, ifd, to, ofd);
    }
    tstamp[0] = asb->sb_atime;
    tstamp[1] = f_mtime ? asb->sb_mtime : time((time_t *) 0);
    utime(to, tstamp);
    return (ifd);
}