Subversion Repositories planix.SVN

#include "lib.h"
#include <unistd.h>
#include <string.h>
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include "sys9.h"
#include "dir.h"

int
rename(const char *from, const char *to)
{
        int n;
        char *f, *t;
        Dir *d, nd;

        if(access(to, 0) >= 0){
                if(_REMOVE(to) < 0){
                        _syserrno();
                        return -1;
                }
        }
        if((d = _dirstat(to)) != nil){
                free(d);
                errno = EEXIST;
                return -1;
        }
        if((d = _dirstat(from)) == nil){
                _syserrno();
                return -1;
        }
        f = strrchr(from, '/');
        t = strrchr(to, '/');
        f = f? f+1 : (char *)from;
        t = t? t+1 : (char *)to;
        n = 0;
        if(f-from==t-to && strncmp(from, to, f-from)==0){
                /* from and to are in same directory (we miss some cases) */
                _nulldir(&nd);
                nd.name = t;
                if(_dirwstat(from, &nd) < 0){
                        _syserrno();
                        n = -1;
                }
        }else{
                /* different directories: have to copy */
                int ffd, tfd;
                char buf[8192];

                tfd = -1;
                if((ffd = _OPEN(from, 0)) < 0 ||
                   (tfd = _CREATE(to, 1, d->mode)) < 0){
                        _CLOSE(ffd);
                        _syserrno();
                        n = -1;
                }
                while(n>=0 && (n = _READ(ffd, buf, 8192)) > 0)
                        if(_WRITE(tfd, buf, n) != n){
                                _syserrno();
                                n = -1;
                        }
                _CLOSE(ffd);
                _CLOSE(tfd);
                if(n>0)
                        n = 0;
                if(n == 0) {
                        if(_REMOVE(from) < 0){
                                _syserrno();
                                return -1;
                        }
                }
        }
        free(d);
        return n;
}