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Comment:Updated inode generation to be FNV-1a
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SHA1: fac74d236fff99c5de7240e21ce821f4076da1cc
User & Date: rkeene on 2014-11-15 19:34:02
Other Links: manifest | tags
Context
2014-11-17
16:51
Added timeout (30s) for DB operations to avoid locking failures being immediately returned check-in: dd0cc55f82 user: rkeene tags: trunk
2014-11-15
19:34
Updated inode generation to be FNV-1a check-in: fac74d236f user: rkeene tags: trunk
19:17
Added missing Tcl_Preserve() call check-in: 71bdb44ec6 user: rkeene tags: trunk
Changes
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Modified appfsd.c from [430dbcdf6b] to [cbe8db4a9d].

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	return(retval);
}

/*
 * Generate an inode for a given path.  The inode should be computed in such
 * a way that it is unlikely to be duplicated and remains the same for a given
 * file
 *
 * Current implementation is an FNV-1a 32-bit
 */
#if UINT_MAX < 4294967295
#error Integer size is too small 
#endif
static unsigned long long appfs_get_path_inode(const char *path) {
	int retval;
	const char *p;
	unsigned int retval;
	const unsigned char *p;

	retval = 10;
	retval = 2166136261; /* FNV-1a 32-bit offset_basis */

	for (p = path; *p; p++) {
	for (p = (unsigned char *) path; *p; p++) {
		retval %= 4290960290ULL;
		retval += *p;
		retval <<= 6;
		retval ^= (int) *p;
#if 0
		retval *= 16777619; /* FNV-1a 32-bit prime */
#else
		/* GCC Optimized replacement */
		retval += (retval << 1) + (retval << 4) + (retval << 7) + (retval << 8) + (retval << 24);
#endif
	}

	retval += 10;
	retval %= 4294967286ULL;
	retval += 10;

	return(retval);
}

/*
 * Cache Get Path Info lookups for speed
 */
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