tmpname

tmpname.h

#ifndef TMP_NAME_H
#define TMP_NAME_H 1

#ifdef __cplusplus
extern "C" {
#endif

#include <stdlib.h>
#include <sys/time.h>
#include <string.h>
#include <time.h>
#include <unistd.h>


#define PATHLEN 20 //XXX: modify this if necessary

char str[PATHLEN];

// http://www.concentric.net/~Ttwang/tech/inthash.htm
static unsigned long mix(unsigned long a, unsigned long b, unsigned long c)
{
	a=a-b;  a=a-c;  a=a^(c >> 13);
	b=b-c;  b=b-a;  b=b^(a << 8);
	c=c-a;  c=c-b;  c=c^(b >> 13);
	a=a-b;  a=a-c;  a=a^(c >> 12);
	b=b-c;  b=b-a;  b=b^(a << 16);
	c=c-a;  c=c-b;  c=c^(b >> 5);
	a=a-b;  a=a-c;  a=a^(c >> 3);
	b=b-c;  b=b-a;  b=b^(a << 10);
	c=c-a;  c=c-b;  c=c^(b >> 15);
	return c;
}

static inline char *tmpname(void)
{
	int i, len;
	const char dir[] = "/mnt/pmem/"; //XXX: modify this if necessary
	const char charset[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
	unsigned long seed = mix((unsigned long)clock(), (unsigned long)time(NULL), (unsigned long)getpid());

	srand(seed);

	len = strlen(dir);
	for (i = 0; i < len; i++)
		str[i] = dir[i];
	for (i = len; i < PATHLEN; i++) {
		str[i] = charset[rand() % (int) (sizeof charset - 1)];
	}
	str[i] = '\0';
	return str;
}

#ifdef __cplusplus
}
#endif
#endif  /* tmpname.h */