+++ /dev/null
-/*
- * Copyright (c) 1995-2006, Index Data
- * All rights reserved.
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- * * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * * Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * * Neither the name of Index Data nor the names of its contributors
- * may be used to endorse or promote products derived from this
- * software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY
- * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE REGENTS AND CONTRIBUTORS BE LIABLE FOR ANY
- * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
- * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
- * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-/* $Id: nfa.h,v 1.12 2006-10-09 21:02:41 adam Exp $ */
-/**
- * \file nfa.h
- * \brief NFA for character set normalizing
- *
- * The NFA is a character mathcing device. It consists of states
- * and transitions between them. Each transition has a condition, which
- * is a range of values.
- *
- * When matching, we always start at the first state, and find the longest
- * possible sequence of input characters that match the ranges in the
- * conditions, and that leads into a terminal state.
- *
- * Separate from this we have converters. Those can often be used
- * together with a NFA (think match-pattern and replace-pattern).
- *
- * A converter is a routine that produces some output. It can translate a
- * range of characters into another range, emit a constant string, or
- * something like that.
- *
- */
-
-#ifndef YAZ_NFA_H
-#define YAZ_NFA_H
-
-#include <yaz/yconfig.h>
-#include <stdio.h>
-
-YAZ_BEGIN_CDECL
-
-/** \name return codes and data types*/
-/* \{ */
-/** \brief Success */
-#define YAZ_NFA_SUCCESS 0
-
-/** \brief no match found */
-#define YAZ_NFA_NOMATCH 1
-
-/** \brief Need more input */
-#define YAZ_NFA_OVERRUN 2
-
-/** \brief The NFA is looping */
-#define YAZ_NFA_LOOP 3
-
-/** \brief no room in output buffer */
-#define YAZ_NFA_NOSPACE 4
-
-/** \brief tryig to set a result when one already exists*/
-#define YAZ_NFA_ALREADY 5
-
-/** \brief Attempting to set an end to a backref that has not been started */
-#define YAZ_NFA_NOSTART 6
-
-/** \brief Asking for a non-existing backref */
-#define YAZ_NFA_NOSUCHBACKREF 7
-
-/** \brief Internal error, should never happen */
-#define YAZ_NFA_INTERNAL 8
-
-
-/** \brief Internal character type. 32-bit unicode! */
-typedef unsigned int yaz_nfa_char;
-
-
-/** \brief The NFA itself
- * The internals are hidden in nfa.c */
-typedef struct yaz_nfa yaz_nfa;
-
-/** \brief A state of the NFA */
-typedef struct yaz_nfa_state yaz_nfa_state;
-
-/** \brief Transition from one state to another */
-typedef struct yaz_nfa_transition yaz_nfa_transition;
-
-/** \brief A converter produces some output to a buffer */
-typedef struct yaz_nfa_converter yaz_nfa_converter;
-
-/* \} */
-
-/** \name Low-level interface to building the NFA */
-/* \{ */
-
-/** \brief Initialize the NFA without any states in it
- *
- * \return a pointer to the newly created NFA
- *
- * */
-yaz_nfa *yaz_nfa_init(void);
-
-/** \brief Destroy the whole thing */
-void yaz_nfa_destroy(
- yaz_nfa *n /** the nfa to destroy */
- );
-
-/** \brief Add a normal state to the NFA.
- *
- * The first state added will become the starting point.
- * Returns a pointer to it, which you can safely ignore, or use in building
- * transitions.
- */
-yaz_nfa_state *yaz_nfa_add_state(
- yaz_nfa *n /** The NFA to add the state to */
- );
-
-
-/** \brief Sets the result pointer to a state
- *
- * \param n the NFA itself
- * \param s the state to which the result will be added
- * \param result the result pointer
- *
- * Sets the result pointer of a state. If already set, returns an error. Call
- * with a NULL pointer to clear the result, before setting a new one.
- *
- * \retval YAZ_NFA_SUCCESS ok
- * \retval YAZ_NFA_ALREADY The state already has a result!
- */
-int yaz_nfa_set_result(
- yaz_nfa *n,
- yaz_nfa_state *s,
- void *result
- );
-
-/** \brief Gets the result pointer from a state
- *
- * \retval NULL if no result set
- */
-void *yaz_nfa_get_result(
- yaz_nfa *n /** The NFA itself */,
- yaz_nfa_state *s /** The state whose result you want */);
-
-/** \brief Set a backref point to a state.
- *
- * Each state can be the beginning and/or ending point of a backref
- * sequence. This call sets one of those flags in the state. After
- * matching, we can get hold of the backrefs that matched, and use
- * them in our translations. The numbering of backrefs start at 1,
- * not zero!
- *
- * \param n the nfa
- * \param s the state to add to
- * \param backref_number is the number of the back reference.
- * \param is_start is 1 for start of the backref, 0 for end
- *
- * \retval YAZ_NFA_SUCCESS for OK
- * \retval YAZ_NFA_ALREADY if the backref is already set
- * \retval YAZ_NFA_NOSTART for ending a backref that has not been started
- *
- */
-
-int yaz_nfa_set_backref_point(yaz_nfa *n, yaz_nfa_state *s,
- int backref_number,
- int is_start );
-
-/** \brief Get the backref point of a state
- *
- * \param n the nfa
- * \param s the state to add to
- * \param is_start is 1 for start of the backref, 0 for end
- * \return the backref number associated with the state, or 0 if none.
- */
-
-int yaz_nfa_get_backref_point(yaz_nfa *n, yaz_nfa_state *s,
- int is_start );
-
-/** \brief Add a transition to the NFA.
- *
- * Add a transition between two existing states. The condition
- * is (as always) a range of yaz_nfa_chars.
- * \param n the nfa
- * \param from_state which state the transition is from. null=initial
- * \param to_state where the transition goes to
- * \param range_start is the beginning of the range of values
- * \param range_end is the end of the range of values
- **/
-void yaz_nfa_add_transition(yaz_nfa *n,
- yaz_nfa_state *from_state,
- yaz_nfa_state *to_state,
- yaz_nfa_char range_start,
- yaz_nfa_char range_end);
-
-/** \brief Add an empty (epsilon) transition.
- *
- * \param n the nfa
- * \param from_state which state the transition is from
- * \param to_state where the transition goes to
- **/
-void yaz_nfa_add_empty_transition( yaz_nfa *n,
- yaz_nfa_state *from_state,
- yaz_nfa_state *to_state);
-
-/** \brief Add a translation from a range to the NFA.
- *
- * \param n the nfa
- * \param st the state to add this to. If null, adds to the initial state
- * \param range_start is the beginning of the range of values
- * \param range_end is the end of the range of values
- *
- * Checks if we already have a transition like this. If so, does not add
- * a new one, but returns the target state. Otherwise creates a new state,
- * and a transition to it.
- */
-yaz_nfa_state *yaz_nfa_add_range( yaz_nfa *n,
- yaz_nfa_state *st,
- yaz_nfa_char range_start,
- yaz_nfa_char range_end );
-
-/** \brief Add a sequence of transitions and states.
- *
- * \param n the nfa
- * \param s the state to add this to. If null, adds to the initial state
- * \param seq is a sequence of yaz_fna_chars.
- * \param seq_len is the length of the sequence
- * \return the final state
- *
- * Starting from state s (or from the initial state, if s is
- * null), finds as much of seq as possible and inserts the rest.
- */
-yaz_nfa_state *yaz_nfa_add_sequence( yaz_nfa *n,
- yaz_nfa_state *s,
- yaz_nfa_char *seq,
- size_t seq_len );
-
-/** \} */
-
-/** \name Low-level interface for mathcing the NFA. */
-/*
- * These do the actual matching. They know nothing of
- * the type of the result pointers
- */
-/** \{ */
-
-/** \brief Find the longest possible match.
- *
- * \param n the nfa itself
- * \param inbuff buffer of input data. Will be incremented when match
- * \param incharsleft max number of inchars to use from inbuff. decrements.
- * \param result the result pointer from the nfa (what ever that is)
- *
- * In case of errors, returns the best match so far,
- * which the caller is free to ignore.
- *
- * \retval YAZ_NFA_SUCCESS success
- * \retval YAZ_NFA_NOMATCH no match found
- * \retval YAZ_NFA_OVERRUN overrun of input buffer
- * \retval YAZ_NFA_LOOP looping too far
- *
- */
-
-int yaz_nfa_match(yaz_nfa *n, yaz_nfa_char **inbuff, size_t *incharsleft,
- void **result );
-
-/** \brief Get a back reference after a successfull match.
- *
- * \param n the nfa
- * \param backref_no the number of the backref to get
- * \param start beginning of the matching substring
- * \param end end of the matching substring
- *
- * Returns pointers to the beginning and end of a backref, or null
- * pointers if one endpoint not met. Those pointers point to the
- * original buffer that was matched, so the caller will not have to
- * worry about freeing anything special.
- *
- * It is technically possible to create NFAs that meet the start but
- * not the end of a backref. It is up to the caller to decide how
- * to handle such a situation.
- *
- * \retval YAZ_NFA_SUCCESS OK
- * \retval YAZ_NFA_NOMATCH The NFA hasn't matched anything, no backref
- * \retval YAZ_NFA_NOSUCHBACKREF no such backref
- */
-
-int yaz_nfa_get_backref( yaz_nfa *n,
- int backref_no,
- yaz_nfa_char **start,
- yaz_nfa_char **end );
-
-/* \} */
-
-/** \name Low-level interface to the converters */
-/* These produce some output text into a buffer. There are a few
- * kinds of converters, each producing different type of output.
- */
-/* \{ */
-
-/** \brief Create a string converter.
- * \param n the nfa
- * \param string the string to output
- * \param length how many chars in the string
- *
- * This converter produces a constant string in the output
- */
-yaz_nfa_converter *yaz_nfa_create_string_converter (
- yaz_nfa *n,
- yaz_nfa_char *string,
- size_t length );
-
-/** \brief Create a backref converter
- * \param n the nfa
- * \param backref_no The backreference to reproduce
- *
- * This converter copies a backref into the output buffer
- */
-yaz_nfa_converter *yaz_nfa_create_backref_converter (
- yaz_nfa *n, int backref_no );
-
-
-/** \brief Create a charcater range converter
- * \param n the nfa
- * \param backref_no The backreference to reproduce
- * \param from_char the first character of the original range
- * \param to_char the first character of the target range
- *
- * This converter takes a backreference, and shifts the characters
- * by a constant value. For example, translating a-z to A-Z.
- * Note that backref 0 is always the last character that matched a
- * range, even if no backrefs were defined in teh nfa. This makes
- * it pretty useful with this converter.
- *
- */
-yaz_nfa_converter *yaz_nfa_create_range_converter (
- yaz_nfa *n, int backref_no,
- yaz_nfa_char from_char,
- yaz_nfa_char to_char);
-
-
-/** \brief Connects converters in a chain.
- * \param n the nfa (mostly for nmem access)
- * \param startpoint the first converter in the chain
- * \param newconverter
- *
- * Places the new converter at the end of the chain that starts from
- * startpoint.
- *
- */
-void yaz_nfa_append_converter (
- yaz_nfa *n,
- yaz_nfa_converter *startpoint,
- yaz_nfa_converter *newconverter);
-
-/** brief Runs the chain of converters.
- * \param n the nfa (mostly for nmem access)
- * \param c the first converter in a chain
- * \param outbuff buffer to write the output in. Increments the ptr.
- * \param outcharsleft how many may we write
- *
- * Runs the converters in the chain, placing output into outbuff
- * (and incrementing the pointer).
- *
- * \retval YAZ_NFA_SUCCESS OK
- * \retval YAZ_NFA_NOMATCH no match to get backrefs from
- * \retval YAZ_NFA_NOSPACE no room in outbuf
- * \retval YAZ_NFA_INTERNAL Should never happen
- *
- */
-int yaz_nfa_run_converters(
- yaz_nfa *n,
- yaz_nfa_converter *c,
- yaz_nfa_char **outbuff,
- size_t *outcharsleft);
-
-/** \} */
-
-/** \name High-level interface to the NFA */
-/* This interface combines the NFA and converters, for ease of
- * access. There are a few calls to build a complete system, and a call
- * to do the actual conversion.
- */
-/* \{ */
-
-/** \brief Add a rule that converts one string to another ('IX' -> '9')
- *
- * \param n The nfa itself
- * \param from_string the string to match
- * \param from_length length of the from_string
- * \param to_string the string to write in the output
- * \param to_length length of the to_string
- *
- * Adds a matching rule and a string converter to the NFA.
- * Can be used for converting strings into nothing, for example,
- * to remove markup.
- *
- * \retval YAZ_NFA_SUCCESS OK
- * \retval YAZ_NFA_ALREADY Conflict with some other rule
- *
- */
-int yaz_nfa_add_string_rule( yaz_nfa *n,
- yaz_nfa_char *from_string,
- size_t from_length,
- yaz_nfa_char *to_string,
- size_t to_length);
-
-/** brief Just like yaz_nfa_add_string_rule, but takes the strings in ascii
- *
- * \param n The nfa itself
- * \param from_string the string to match
- * \param to_string the string to write in the output
- *
- * Like yaz_nfa_add_string_rule, this adds a rule to translate a string
- * into another. The only difference is that this one takes the strings as
- * normal char *, which means that no high-valued unicodes can be handled,
- * and that this one uses null-terminated strings. In short, this is a
- * simplified version mostly intended for tests and other small uses.
- *
- * \retval YAZ_NFA_SUCCESS OK
- * \retval YAZ_NFA_ALREADY Conflict with some other rule
- */
-int yaz_nfa_add_ascii_string_rule( yaz_nfa *n,
- char *from_string,
- char *to_string);
-
-
-/** \brief Add a rule that converts a character range
- *
- * \param n The nfa itself
- * \param range_start Where the matching range starts
- * \param range_end Where the matching range ends
- * \param output_range_start Where the resulting range starts
- *
- *
- * Adds a character range rule to the NFA. The range to be converted
- * is defined by the range_start and range_end parameters. The output
- * range starts at output_range_start, and is automatically as long
- * as the input range.
- *
- * Useful for alphabet normalizing [a-z] -> [A-Z]
- *
- * \retval YAZ_NFA_SUCCESS OK
- * \retval YAZ_NFA_ALREADY Conflict with some other rule
- */
-int yaz_nfa_add_char_range_rule (yaz_nfa *n,
- yaz_nfa_char range_start,
- yaz_nfa_char range_end,
- yaz_nfa_char output_range_start);
-
-/** \brief Add a rule that converts a character range to a string
- *
- * \param n The nfa itself
- * \param range_start Where the matching range starts
- * \param range_end Where the matching range ends
- * \param to_string the string to write in the output
- * \param to_length length of the to_string
- *
- * \retval YAZ_NFA_SUCCESS OK
- * \retval YAZ_NFA_ALREADY Conflict with some other rule
- *
- * Adds a character range match rule, and a string converter.
- *
- * Useful in converting a range of special characters into (short?)
- * strings of whitespace, or even to nothing at all.
- */
-int yaz_nfa_add_char_string_rule (yaz_nfa *n,
- yaz_nfa_char range_start,
- yaz_nfa_char range_end,
- yaz_nfa_char* to_string,
- size_t to_length);
-
-/** \brief Converts one 'slice' that is, the best matching rule.
- *
- * \param n the nfa itself
- * \param inbuff buffer of input data. Will be incremented when match
- * \param incharsleft max number of inchars to use from inbuff. decrements.
- * \param outbuff buffer for output data. Will be incremented when match
- * \param outcharsleft max number of chars to write to outbuff.
- *
- * \retval YAZ_NFA_SUCCESS OK
- * \retval YAZ_NFA_OVERRUN No more input data, some pattern could match
- * \retval YAZ_NFA_NOSPACE No room in the putput buffer
- * \retval YAZ_NFA_NOSUCHBACKREF NFA refers to a non-existing backref
- *
- * Finds the best match at the beginning of inbuf, and fires its converter(s)
- * to produce output in outbuff. Increments both inbuf and outbuf pointers and
- * decrements the *charsleft values, so all is ready for calling again, until
- * the buffer is exhausted. That loop is left to the caller, so he can load
- * more data in the buffer in good time.
- *
- * If no match is found, converts one character into itself. If the matcher
- * returns any sort of error, leaves the pointers where they were.
- */
-int yaz_nfa_convert_slice (yaz_nfa *n,
- yaz_nfa_char **inbuff,
- size_t *incharsleft,
- yaz_nfa_char **outbuff,
- size_t *outcharsleft);
-
-
-/* \} */
-
-/** \name Debug routines */
-/* These provide a method for traversing all the states defined
- * in the NFA, for example to release memory allocated in the results,
- * and a simple debug routine to dump the NFA */
-/* \{ */
-
-
-/** \brief Get the first state of the NFA.
- *
- * \param n the nfa
- *
- * Useful for iterating through all states, probably calling get_result
- * for each, and doing something to the results (freeing memory?)
- *
- * \returns a pointer to the first state, or NULL if none.
- */
-yaz_nfa_state *yaz_nfa_get_first(yaz_nfa *n);
-
-/** \brief Get the next state of the NFA.
- *
- * \param n the nfa
- * \param s the state to add to
- * \return the next state, or NULL if no more.
- */
-yaz_nfa_state *yaz_nfa_get_next(yaz_nfa *n, yaz_nfa_state *s);
-
-/** \brief Dump the NFA into a file .
- *
- * \param F The file handle to dump into (null => stdout)
- * \param n the nfa
- * \param strfunc can be used for converting the resultinfo a string.
- *
- * strfunc is a function like
- * char *f( void *result);
- * it takes the result, and converts into a printable string (which
- * must be allocated somewhere by the caller). If the results are
- * already printable, passing a null pointer here prints them with a %s
- *
- */
-void yaz_nfa_dump(FILE *F,
- yaz_nfa *n,
- char *(*strfunc)(void *) );
-
-/** \brief Helper to dump converters
- *
- */
-char *yaz_nfa_dump_converter(void *conv);
-
-/* \} */
-
-
-
-YAZ_END_CDECL
-
-#endif
+++ /dev/null
-/*
- * Copyright (c) 1995-2006, Index Data
- * All rights reserved.
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- * * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * * Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * * Neither the name of Index Data nor the names of its contributors
- * may be used to endorse or promote products derived from this
- * software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY
- * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE REGENTS AND CONTRIBUTORS BE LIABLE FOR ANY
- * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
- * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
- * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-/* $Id: nfaxml.h,v 1.6 2006-10-09 21:02:41 adam Exp $ */
-
-/**
- * \file nfaxml.h
- * \brief Routines for reading NFA specs from an XML file
- *
- * The xml file is something like this (using round brakcets
- * on tags, not to confuse our documentation tools)
- * (?xml ...)
- * (ruleset)
- * (rule)
- * (fromstring) FOO (/fromstring)
- * (tostring) BAR (/tostring)
- * (/rule)
- * (rule)
- * (fromrange) a-z (/fromrange)
- * (torange) A-Z (/torange)
- * (/rule)
- * ...
- *
- * The rules consist of two parts, 'from' and 'to'.
- * From rules can be
- * fromstring (which can be a single character)
- * fromrange (like a-z)
- * (later, perhaps a fromregexp)
- * To rules can be
- * tostring (which can be a single character)
- * torange (only with a fromrange)
- * (later, perhaps backrefs from regexps)
- */
-
-#ifndef YAZ_NFA_XML_H
-#define YAZ_NFA_XML_H
-
-#if YAZ_HAVE_XML2
-
-#include <libxml/parser.h>
-
-#include <yaz/yconfig.h>
-#include <yaz/log.h>
-#include <yaz/nfa.h>
-
-YAZ_BEGIN_CDECL
-
-/** \brief Parse the NFA from a XML document
- *
- * \param doc the xml tree to parse
- * \param filename used for info in error messages
- *
- * \returns either the NFA, or null in case of errors
- *
- * It is up to the caller to destroy the nfa when done.
- *
- * Does not expand XIncludes.
- *
- * In case of errors, returns a null pointer. You can then
- * call xmlGetLastError() to get the details of the error,
- * if you have a recent enough libxml2. Those are already
- * logged in yazlog.
- *
- */
-yaz_nfa *yaz_nfa_parse_xml_doc(xmlDocPtr doc, const char *filename);
-
-
-/** \brief Parse the NFA from a file
- *
- * \param filepath path to the xml file to parse
- * \param error_info will be filled in case of errors
- *
- * \returns either the NFA, or null in case of errors
- *
- * It is up to the caller to destroy the nfa when done.
- *
- * This routine also expands XIncludes.
- *
- * In case of errors, returns a null pointer. You can then
- * call xmlGetLastError() to get the details of the error,
- * if you have a recent enough libxml2. Those are already
- * logged in yazlog.
- *
- */
-yaz_nfa *yaz_nfa_parse_xml_file(const char *filepath);
-
-
-/** \brief Parse the NFA from a memory buffer
- *
- * \param filepath path to the xml file to parse
- * \param error_info will be filled in case of errors
- *
- * \returns either the NFA, or null in case of errors
- *
- * It is up to the caller to destroy the nfa when done.
- *
- * Does not expand XIncludes.
- *
- * In case of errors, returns a null pointer. You can then
- * call xmlGetLastError() to get the details of the error,
- * if you have a recent enough libxml2. Those are already
- * logged in yazlog.
- *
- */
-yaz_nfa *yaz_nfa_parse_xml_memory(const char *xmlbuff, const char *filename);
-
-
-YAZ_END_CDECL
-
-#endif /* YAZ_HAVE_XML2 */
-#endif /* YAZ_NFA_XML_H */
-
-/*
- * Local variables:
- * c-basic-offset: 4
- * indent-tabs-mode: nil
- * End:
- * vim: shiftwidth=4 tabstop=8 expandtab
- */
-
projects / yaz-moved-to-github.git / commitdiff