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    /*	$OpenBSD: mktemp.c,v 1.38 2015/09/13 08:31:47 guenther Exp $ */  | 
    
    
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    /*  | 
    
    
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     * Copyright (c) 1996-1998, 2008 Theo de Raadt  | 
    
    
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     * Copyright (c) 1997, 2008-2009 Todd C. Miller  | 
    
    
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     *  | 
    
    
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     * Permission to use, copy, modify, and distribute this software for any  | 
    
    
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     * purpose with or without fee is hereby granted, provided that the above  | 
    
    
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     * copyright notice and this permission notice appear in all copies.  | 
    
    
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     *  | 
    
    
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     * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES  | 
    
    
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     * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF  | 
    
    
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     * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR  | 
    
    
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     * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES  | 
    
    
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     * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN  | 
    
    
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     * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF  | 
    
    
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     * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.  | 
    
    
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     */  | 
    
    
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    #include <sys/types.h>  | 
    
    
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    #include <sys/stat.h>  | 
    
    
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    #include <errno.h>  | 
    
    
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    #include <fcntl.h>  | 
    
    
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    #include <limits.h>  | 
    
    
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    #include <stdio.h>  | 
    
    
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    #include <stdlib.h>  | 
    
    
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    #include <string.h>  | 
    
    
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    #include <ctype.h>  | 
    
    
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    #include <unistd.h>  | 
    
    
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    #define MKTEMP_NAME	0  | 
    
    
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    #define MKTEMP_FILE	1  | 
    
    
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    #define MKTEMP_DIR	2  | 
    
    
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    #define TEMPCHARS	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"  | 
    
    
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    #define NUM_CHARS	(sizeof(TEMPCHARS) - 1)  | 
    
    
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    #define MIN_X		6  | 
    
    
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    #define MKOTEMP_FLAGS	(O_APPEND | O_CLOEXEC | O_DSYNC | O_RSYNC | O_SYNC)  | 
    
    
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    #ifndef nitems  | 
    
    
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    #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))  | 
    
    
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    #endif  | 
    
    
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    static int  | 
    
    
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    mktemp_internal(char *path, int slen, int mode, int flags)  | 
    
    
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    { | 
    
    
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    	char *start, *cp, *ep;  | 
    
    
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    	const char tempchars[] = TEMPCHARS;  | 
    
    
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    	unsigned int tries;  | 
    
    
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    	struct stat sb;  | 
    
    
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    	size_t len;  | 
    
    
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    	int fd;  | 
    
    
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    	len = strlen(path);  | 
    
    
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    	if (len < MIN_X || slen < 0 || (size_t)slen > len - MIN_X) { | 
    
    
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    		errno = EINVAL;  | 
    
    
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    		return(-1);  | 
    
    
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    	}  | 
    
    
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    	ep = path + len - slen;  | 
    
    
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    	for (start = ep; start > path && start[-1] == 'X'; start--)  | 
    
    
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    		;  | 
    
    
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    	if (ep - start < MIN_X) { | 
    
    
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    		errno = EINVAL;  | 
    
    
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    		return(-1);  | 
    
    
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    	}  | 
    
    
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    	if (flags & ~MKOTEMP_FLAGS) { | 
    
    
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    		errno = EINVAL;  | 
    
    
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    		return(-1);  | 
    
    
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    	}  | 
    
    
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    	flags |= O_CREAT | O_EXCL | O_RDWR;  | 
    
    
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    	tries = INT_MAX;  | 
    
    
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    	do { | 
    
    
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    		cp = start;  | 
    
    
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    		do { | 
    
    
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    			unsigned short rbuf[16];  | 
    
    
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    			unsigned int i;  | 
    
    
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    			/*  | 
    
    
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    			 * Avoid lots of arc4random() calls by using  | 
    
    
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    			 * a buffer sized for up to 16 Xs at a time.  | 
    
    
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    			 */  | 
    
    
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    			arc4random_buf(rbuf, sizeof(rbuf));  | 
    
    
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    			for (i = 0; i < nitems(rbuf) && cp != ep; i++)  | 
    
    
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    				*cp++ = tempchars[rbuf[i] % NUM_CHARS];  | 
    
    
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    		} while (cp != ep);  | 
    
    
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    		switch (mode) { | 
    
    
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    		case MKTEMP_NAME:  | 
    
    
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    			if (lstat(path, &sb) != 0)  | 
    
    
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    				return(errno == ENOENT ? 0 : -1);  | 
    
    
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    			break;  | 
    
    
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    		case MKTEMP_FILE:  | 
    
    
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    			fd = open(path, flags, S_IRUSR|S_IWUSR);  | 
    
    
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    			if (fd != -1 || errno != EEXIST)  | 
    
    
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    				return(fd);  | 
    
    
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    			break;  | 
    
    
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    		case MKTEMP_DIR:  | 
    
    
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    			if (mkdir(path, S_IRUSR|S_IWUSR|S_IXUSR) == 0)  | 
    
    
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    				return(0);  | 
    
    
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    			if (errno != EEXIST)  | 
    
    
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    				return(-1);  | 
    
    
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    			break;  | 
    
    
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    		}  | 
    
    
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    	} while (--tries);  | 
    
    
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    	errno = EEXIST;  | 
    
    
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    	return(-1);  | 
    
    
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    }  | 
    
    
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    char *  | 
    
    
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    _mktemp(char *path)  | 
    
    
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    { | 
    
    
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    	if (mktemp_internal(path, 0, MKTEMP_NAME, 0) == -1)  | 
    
    
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    		return(NULL);  | 
    
    
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    	return(path);  | 
    
    
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    }  | 
    
    
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    __warn_references(mktemp,  | 
    
    
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        "warning: mktemp() possibly used unsafely; consider using mkstemp()");  | 
    
    
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    char *  | 
    
    
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    mktemp(char *path)  | 
    
    
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    { | 
    
    
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    	return(_mktemp(path));  | 
    
    
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    }  | 
    
    
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    int  | 
    
    
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    mkostemps(char *path, int slen, int flags)  | 
    
    
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    { | 
    
    
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    	return(mktemp_internal(path, slen, MKTEMP_FILE, flags));  | 
    
    
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    }  | 
    
    
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    int  | 
    
    
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    mkstemp(char *path)  | 
    
    
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    { | 
    
    
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    	return(mktemp_internal(path, 0, MKTEMP_FILE, 0));  | 
    
    
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    }  | 
    
    
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    DEF_WEAK(mkstemp);  | 
    
    
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    int  | 
    
    
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    mkostemp(char *path, int flags)  | 
    
    
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    { | 
    
    
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    	return(mktemp_internal(path, 0, MKTEMP_FILE, flags));  | 
    
    
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    }  | 
    
    
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    DEF_WEAK(mkostemp);  | 
    
    
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    int  | 
    
    
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    mkstemps(char *path, int slen)  | 
    
    
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    { | 
    
    
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    	return(mktemp_internal(path, slen, MKTEMP_FILE, 0));  | 
    
    
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    }  | 
    
    
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    char *  | 
    
    
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    mkdtemp(char *path)  | 
    
    
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    { | 
    
    
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    	int error;  | 
    
    
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    	error = mktemp_internal(path, 0, MKTEMP_DIR, 0);  | 
    
    
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    	return(error ? NULL : path);  | 
    
    
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    }  |