AI-MegaHAL

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libmegahal.c  view on Meta::CPAN

#else
#include <sys/types.h>
#endif
#include "megahal.h"
#if defined(DEBUG)
#include "debug.h"
#endif

#define P_THINK 40
#define D_KEY 100000
#define V_KEY 50000
#define D_THINK 500000
#define V_THINK 250000

#define MIN(a,b) ((a)<(b))?(a):(b)

#define COOKIE "MegaHALv8"
#define TIMEOUT 1

#define DEFAULT "."

#define COMMAND_SIZE (sizeof(command)/sizeof(command[0]))

#define BYTE1 unsigned char
#define BYTE2 unsigned short

#define BYTE4 unsigned int

#ifdef __mac_os
#define bool Boolean
#endif

#ifdef DOS
#define SEP "\\"
#else
#define SEP "/"
#endif

#ifdef AMIGA
#undef toupper
#define toupper(x) ToUpper(x)
#undef tolower
#define tolower(x) ToLower(x)
#undef isalpha
#define isalpha(x) IsAlpha(_AmigaLocale,x)
#undef isalnum
#define isalnum(x) IsAlNum(_AmigaLocale,x)
#undef isdigit
#define isdigit(x) IsDigit(_AmigaLocale,x)
#undef isspace
#define isspace(x) IsSpace(_AmigaLocale,x)
#endif

#ifndef __mac_os
#undef FALSE
#undef TRUE
typedef enum { FALSE, TRUE } bool;
#endif

typedef struct {
    BYTE1 length;
    char *word;
} STRING;

typedef struct {
    BYTE4 size;
    STRING *entry;
    BYTE2 *index;
} DICTIONARY;

typedef struct {
    BYTE2 size;
    STRING *from;
    STRING *to;
} SWAP;

typedef struct NODE {
    BYTE2 symbol;
    BYTE4 usage;
    BYTE2 count;
    BYTE2 branch;
    struct NODE **tree;
} TREE;

typedef struct {
    BYTE1 order;
    TREE *forward;
    TREE *backward;
    TREE **context;
    DICTIONARY *dictionary;
} MODEL;

typedef enum { UNKNOWN, QUIT, EXIT, SAVE, DELAY, HELP, SPEECH, VOICELIST, VOICE, BRAIN, QUIET} COMMAND_WORDS;

typedef struct {
    STRING word;
    char *helpstring;
    COMMAND_WORDS command;
} COMMAND;

/*===========================================================================*/

static int width=75;
static int order=5;

static bool typing_delay=FALSE;
static bool noprompt=FALSE;
static bool speech=FALSE;
static bool quiet=FALSE;
static bool nowrap=FALSE;
static bool nobanner=FALSE;

static char *errorfilename = "megahal.log";
static char *statusfilename = "megahal.txt";
static DICTIONARY *words=NULL;
static DICTIONARY *greets=NULL;
static MODEL *model=NULL;

static FILE *errorfp;
static FILE *statusfp;

libmegahal.c  view on Meta::CPAN

	output=generate_reply(model, greets);
	write_output(output);
	return 1;
    case QUIET:
	quiet=!quiet;
	return 1;
    default:
	return 0;
    }
    return 0;
}

/*
   megahal_cleanup --

   Clean up everything. Prepare for exit.

  */

void megahal_cleanup(void)
{
    save_model("megahal.brn", model);

#ifdef AMIGA
    CloseLocale(_AmigaLocale);
#endif
}



/*---------------------------------------------------------------------------*/

/*
 *		Function:	Execute_Command
 *
 *		Purpose:		Detect whether the user has typed a command, and
 *						execute the corresponding function.
 */
COMMAND_WORDS execute_command(DICTIONARY *words, int *position)
{
    unsigned int i;
    unsigned int j;

    /*
     *		If there is only one word, then it can't be a command.
     */
    *position=words->size+1;
    if(words->size<=1) return(UNKNOWN);

    /*
     *		Search through the word array.  If a command prefix is found,
     *		then try to match the following word with a command word.  If
     *		a match is found, then return a command identifier.  If the
     *		Following word is a number, then change the judge.  Otherwise,
     *		continue the search.
     */
    for(i=0; i<words->size-1; ++i)
	/*
	 *		The command prefix was found.
	 */
	if(words->entry[i].word[words->entry[i].length - 1] == '#') {
	    /*
	     *		Look for a command word.
	     */
	    for(j = 0; j < COMMAND_SIZE; ++j)
		if(wordcmp(command[j].word, words->entry[i + 1]) == 0) {
		    *position = i + 1;
		    return(command[j].command);
		}
	}

    return(UNKNOWN);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	ExitHAL
 *
 *		Purpose:		Terminate the program.
 */
void exithal(void)
{
#ifdef __mac_os
    /*
     *		Must be called because it does use some system memory
     */
    if (gSpeechChannel) {
	StopSpeech(gSpeechChannel);
	DisposeSpeechChannel(gSpeechChannel);
	gSpeechChannel = nil;
    }
#endif

    exit(0);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Read_Input
 *
 *		Purpose:		Read an input string from the user.
 */
char *read_input(char *prompt)
{
    static char *input=NULL;
    bool finish;
    int length;
    int c;

    /*
     *		Perform some initializations.  The finish boolean variable is used
     *		to detect a double line-feed, while length contains the number of
     *		characters in the input string.
     */
    finish=FALSE;
    length=0;
    if(input==NULL) {
	input=(char *)malloc(sizeof(char));
	if(input==NULL) {
	    error("read_input", "Unable to allocate the input string");
	    return(input);
	}
    }

    /*
     *		Display the prompt to the user.
     */
    fprintf(stdout, prompt);
    fflush(stdout);

    /*
     *		Loop forever, reading characters and putting them into the input
     *		string.
     */
    while(TRUE) {

	/*
	 *		Read a single character from stdin.
	 */
	c=getc(stdin);

	/*
	 *		If the character is a line-feed, then set the finish variable
	 *		to TRUE.  If it already is TRUE, then this is a double line-feed,
	 *		in which case we should exit.  After a line-feed, display the
	 *		prompt again, and set the character to the space character, as
	 *		we don't permit linefeeds to appear in the input.
	 */
	if((char)(c)=='\n') {
	    if(finish==TRUE) break;
	    fprintf(stdout, prompt);
	    fflush(stdout);
	    finish=TRUE;
	    c=32;
	} else {
	    finish=FALSE;
	}

	/*
	 *		Re-allocate the input string so that it can hold one more
	 *		character.
	 */
	++length;
	input=(char *)realloc((char *)input,sizeof(char)*(length+1));
	if(input==NULL) {
	    error("read_input", "Unable to re-allocate the input string");
	    return(NULL);
	}

	/*
	 *		Add the character just read to the input string.
	 */
	input[length-1]=(char)c;
	input[length]='\0';
    }

    while(isspace(input[length-1])) --length;
    input[length]='\0';

    /*
     *		We have finished, so return the input string.
     */
    return(input);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Initialize_Error
 *
 *		Purpose:		Close the current error file pointer, and open a new one.
 */
bool initialize_error(char *filename)
{
    if(errorfp!=stderr) fclose(errorfp);

    if(filename==NULL) return(TRUE);

    errorfp = fopen(filename, "a");
    if(errorfp==NULL) {
	errorfp=stderr;
	return(FALSE);
    }
    return(print_header(errorfp));
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Error
 *
 *		Purpose:		Print the specified message to the error file.
 */
void error(char *title, char *fmt, ...)
{
    va_list argp;

    fprintf(errorfp, "%s: ", title);
    va_start(argp, fmt);
    vfprintf(errorfp, fmt, argp);
    va_end(argp);
    fprintf(errorfp, ".\n");
    fflush(errorfp);

    //    fprintf(stderr, "MegaHAL died for some reason; check the error log.\n");

    exit(1);
}

/*---------------------------------------------------------------------------*/

bool warn(char *title, char *fmt, ...)
{
    va_list argp;

    fprintf(errorfp, "%s: ", title);
    va_start(argp, fmt);
    vfprintf(errorfp, fmt, argp);

libmegahal.c  view on Meta::CPAN


/*---------------------------------------------------------------------------*/

/*
 *		Function:	Add_Word
 *
 *		Purpose:		Add a word to a dictionary, and return the identifier
 *						assigned to the word.  If the word already exists in
 *						the dictionary, then return its current identifier
 *						without adding it again.
 */
BYTE2 add_word(DICTIONARY *dictionary, STRING word)
{
    unsigned int i;
    int position;
    bool found;

    /*
     *		If the word's already in the dictionary, there is no need to add it
     */
    position=search_dictionary(dictionary, word, &found);
    if(found==TRUE) goto succeed;

    /*
     *		Increase the number of words in the dictionary
     */
    dictionary->size+=1;

    /*
     *		Allocate one more entry for the word index
     */
    if(dictionary->index==NULL) {
	dictionary->index=(BYTE2 *)malloc(sizeof(BYTE2)*
					  (dictionary->size));
    } else {
	dictionary->index=(BYTE2 *)realloc((BYTE2 *)
					   (dictionary->index),sizeof(BYTE2)*(dictionary->size));
    }
    if(dictionary->index==NULL) {
	error("add_word", "Unable to reallocate the index.");
	goto fail;
    }

    /*
     *		Allocate one more entry for the word array
     */
    if(dictionary->entry==NULL) {
	dictionary->entry=(STRING *)malloc(sizeof(STRING)*(dictionary->size));
    } else {
	dictionary->entry=(STRING *)realloc((STRING *)(dictionary->entry),
					    sizeof(STRING)*(dictionary->size));
    }
    if(dictionary->entry==NULL) {
	error("add_word", "Unable to reallocate the dictionary to %d elements.", dictionary->size);
	goto fail;
    }

    /*
     *		Copy the new word into the word array
     */
    dictionary->entry[dictionary->size-1].length=word.length;
    dictionary->entry[dictionary->size-1].word=(char *)malloc(sizeof(char)*
							      (word.length));
    if(dictionary->entry[dictionary->size-1].word==NULL) {
	error("add_word", "Unable to allocate the word.");
	goto fail;
    }
    for(i=0; i<word.length; ++i)
	dictionary->entry[dictionary->size-1].word[i]=word.word[i];

    /*
     *		Shuffle the word index to keep it sorted alphabetically
     */
    for(i=(dictionary->size-1); i>position; --i)
	dictionary->index[i]=dictionary->index[i-1];

    /*
     *		Copy the new symbol identifier into the word index
     */
    dictionary->index[position]=dictionary->size-1;

succeed:
    return(dictionary->index[position]);

fail:
    return(0);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Search_Dictionary
 *
 *		Purpose:		Search the dictionary for the specified word, returning its
 *						position in the index if found, or the position where it
 *						should be inserted otherwise.
 */
int search_dictionary(DICTIONARY *dictionary, STRING word, bool *find)
{
    int position;
    int min;
    int max;
    int middle;
    int compar;

    /*
     *		If the dictionary is empty, then obviously the word won't be found
     */
    if(dictionary->size==0) {
	position=0;
	goto notfound;
    }

    /*
     *		Initialize the lower and upper bounds of the search
     */
    min=0;
    max=dictionary->size-1;
    /*
     *		Search repeatedly, halving the search space each time, until either
     *		the entry is found, or the search space becomes empty
     */
    while(TRUE) {
	/*
	 *		See whether the middle element of the search space is greater
	 *		than, equal to, or less than the element being searched for.
	 */
	middle=(min+max)/2;

libmegahal.c  view on Meta::CPAN

	    position=middle;
	    goto found;
	} else if(compar>0) {
	    if(max==middle) {
		position=middle+1;
		goto notfound;
	    }
	    min=middle+1;
	} else {
	    if(min==middle) {
		position=middle;
		goto notfound;
	    }
	    max=middle-1;
	}
    }

found:
    *find=TRUE;
    return(position);

notfound:
    *find=FALSE;
    return(position);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Find_Word
 *
 *		Purpose:		Return the symbol corresponding to the word specified.
 *						We assume that the word with index zero is equal to a
 *						NULL word, indicating an error condition.
 */
BYTE2 find_word(DICTIONARY *dictionary, STRING word)
{
    int position;
    bool found;

    position=search_dictionary(dictionary, word, &found);

    if(found==TRUE) return(dictionary->index[position]);
    else return(0);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Wordcmp
 *
 *		Purpose:		Compare two words, and return an integer indicating whether
 *						the first word is less than, equal to or greater than the
 *						second word.
 */
int wordcmp(STRING word1, STRING word2)
{
    unsigned int i;
    unsigned int bound;

    bound=MIN(word1.length,word2.length);

    for(i=0; i<bound; ++i)
	if(toupper(word1.word[i])!=toupper(word2.word[i]))
	    return((int)(toupper(word1.word[i])-toupper(word2.word[i])));

    if(word1.length<word2.length) return(-1);
    if(word1.length>word2.length) return(1);

    return(0);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Free_Dictionary
 *
 *		Purpose:		Release the memory consumed by the dictionary.
 */
void free_dictionary(DICTIONARY *dictionary)
{
    if(dictionary==NULL) return;
    if(dictionary->entry!=NULL) {
	free(dictionary->entry);
	dictionary->entry=NULL;
    }
    if(dictionary->index!=NULL) {
	free(dictionary->index);
	dictionary->index=NULL;
    }
    dictionary->size=0;
}

/*---------------------------------------------------------------------------*/

void free_model(MODEL *model)
{
    if(model==NULL) return;
    if(model->forward!=NULL) {
	free_tree(model->forward);
    }
    if(model->backward!=NULL) {
	free_tree(model->backward);
    }
    if(model->context!=NULL) {
	free(model->context);
    }
    if(model->dictionary!=NULL) {
	free_dictionary(model->dictionary);
	free(model->dictionary);
    }
    free(model);
}

/*---------------------------------------------------------------------------*/

void free_tree(TREE *tree)
{
    static int level=0;
    unsigned int i;

    if(tree==NULL) return;

    if(tree->tree!=NULL) {
	if(level==0) progress("Freeing tree", 0, 1);
	for(i=0; i<tree->branch; ++i) {
	    ++level;
	    free_tree(tree->tree[i]);

libmegahal.c  view on Meta::CPAN


    dictionary->size=0;
    dictionary->index=NULL;
    dictionary->entry=NULL;

    return(dictionary);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Save_Dictionary
 *
 *		Purpose:		Save a dictionary to the specified file.
 */
void save_dictionary(FILE *file, DICTIONARY *dictionary)
{
    unsigned int i;

    fwrite(&(dictionary->size), sizeof(BYTE4), 1, file);
    progress("Saving dictionary", 0, 1);
    for(i=0; i<dictionary->size; ++i) {
	save_word(file, dictionary->entry[i]);
	progress(NULL, i, dictionary->size);
    }
    progress(NULL, 1, 1);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Load_Dictionary
 *
 *		Purpose:		Load a dictionary from the specified file.
 */
void load_dictionary(FILE *file, DICTIONARY *dictionary)
{
    unsigned int i;
    int size;

    fread(&size, sizeof(BYTE4), 1, file);
    progress("Loading dictionary", 0, 1);
    for(i=0; i<size; ++i) {
	load_word(file, dictionary);
	progress(NULL, i, size);
    }
    progress(NULL, 1, 1);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Save_Word
 *
 *		Purpose:		Save a dictionary word to a file.
 */
void save_word(FILE *file, STRING word)
{
    unsigned int i;

    fwrite(&(word.length), sizeof(BYTE1), 1, file);
    for(i=0; i<word.length; ++i)
	fwrite(&(word.word[i]), sizeof(char), 1, file);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Load_Word
 *
 *		Purpose:		Load a dictionary word from a file.
 */
void load_word(FILE *file, DICTIONARY *dictionary)
{
    unsigned int i;
    STRING word;

    fread(&(word.length), sizeof(BYTE1), 1, file);
    word.word=(char *)malloc(sizeof(char)*word.length);
    if(word.word==NULL) {
	error("load_word", "Unable to allocate word");
	return;
    }
    for(i=0; i<word.length; ++i)
	fread(&(word.word[i]), sizeof(char), 1, file);
    add_word(dictionary, word);
    free(word.word);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	New_Node
 *
 *		Purpose:		Allocate a new node for the n-gram tree, and initialise
 *						its contents to sensible values.
 */
TREE *new_node(void)
{
    TREE *node=NULL;

    /*
     *		Allocate memory for the new node
     */
    node=(TREE *)malloc(sizeof(TREE));
    if(node==NULL) {
	error("new_node", "Unable to allocate the node.");
	goto fail;
    }

    /*
     *		Initialise the contents of the node
     */
    node->symbol=0;
    node->usage=0;
    node->count=0;
    node->branch=0;
    node->tree=NULL;

    return(node);

fail:
    if(node!=NULL) free(node);
    return(NULL);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	New_Model
 *
 *		Purpose:		Create and initialise a new ngram model.
 */
MODEL *new_model(int order)
{
    MODEL *model=NULL;

    model=(MODEL *)malloc(sizeof(MODEL));
    if(model==NULL) {
	error("new_model", "Unable to allocate model.");
	goto fail;
    }

    model->order=order;

libmegahal.c  view on Meta::CPAN

    BYTE2 symbol;

    /*
     *		We only learn from inputs which are long enough
     */
    if(words->size<=(model->order)) return;

    /*
     *		Train the model in the forwards direction.  Start by initializing
     *		the context of the model.
     */
    initialize_context(model);
    model->context[0]=model->forward;
    for(i=0; i<words->size; ++i) {
	/*
	 *		Add the symbol to the model's dictionary if necessary, and then
	 *		update the forward model accordingly.
	 */
	symbol=add_word(model->dictionary, words->entry[i]);
	update_model(model, symbol);
    }
    /*
     *		Add the sentence-terminating symbol.
     */
    update_model(model, 1);

    /*
     *		Train the model in the backwards direction.  Start by initializing
     *		the context of the model.
     */
    initialize_context(model);
    model->context[0]=model->backward;
    for(i=words->size-1; i>=0; --i) {
	/*
	 *		Find the symbol in the model's dictionary, and then update
	 *		the backward model accordingly.
	 */
	symbol=find_word(model->dictionary, words->entry[i]);
	update_model(model, symbol);
    }
    /*
     *		Add the sentence-terminating symbol.
     */
    update_model(model, 1);

    return;
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Train
 *
 *		Purpose:	 	Infer a MegaHAL brain from the contents of a text file.
 */
void train(MODEL *model, char *filename)
{
    FILE *file;
    char buffer[1024];
    DICTIONARY *words=NULL;
    int length;

    if(filename==NULL) return;

    file=fopen(filename, "r");
    if(file==NULL) {
	printf("Unable to find the personality %s\n", filename);
	return;
    }

    fseek(file, 0, 2);
    length=ftell(file);
    rewind(file);

    words=new_dictionary();

    progress("Training from file", 0, 1);
    while(!feof(file)) {

	if(fgets(buffer, 1024, file)==NULL) break;
	if(buffer[0]=='#') continue;

	buffer[strlen(buffer)-1]='\0';

	upper(buffer);
	make_words(buffer, words);
	learn(model, words);

	progress(NULL, ftell(file), length);

    }
    progress(NULL, 1, 1);

    free_dictionary(words);
    fclose(file);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Show_Dictionary
 *
 *		Purpose:		Display the dictionary for training purposes.
 */
void show_dictionary(DICTIONARY *dictionary)
{
    register int i;
    register int j;
    FILE *file;

    file=fopen("megahal.dic", "w");
    if(file==NULL) {
	warn("show_dictionary", "Unable to open file");
	return;
    }

    for(i=0; i<dictionary->size; ++i) {
	for(j=0; j<dictionary->entry[i].length; ++j)
	    fprintf(file, "%c", dictionary->entry[i].word[j]);
	fprintf(file, "\n");
    }

    fclose(file);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Save_Model
 *
 *		Purpose:		Save the current state to a MegaHAL brain file.
 */
void save_model(char *modelname, MODEL *model)
{
    FILE *file;
    static char *filename=NULL;

    if(filename==NULL) filename=(char *)malloc(sizeof(char)*1);

    /*
     *    Allocate memory for the filename
     */
    filename=(char *)realloc(filename,
			     sizeof(char)*(strlen(directory)+strlen(SEP)+12));
    if(filename==NULL) error("save_model","Unable to allocate filename");

    show_dictionary(model->dictionary);
    if(filename==NULL) return;

    sprintf(filename, "%s%smegahal.brn", directory, SEP);
    file=fopen(filename, "wb");
    if(file==NULL) {
	warn("save_model", "Unable to open file `%s'", filename);
	return;
    }

    fwrite(COOKIE, sizeof(char), strlen(COOKIE), file);
    fwrite(&(model->order), sizeof(BYTE1), 1, file);
    save_tree(file, model->forward);
    save_tree(file, model->backward);
    save_dictionary(file, model->dictionary);

    fclose(file);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Save_Tree
 *
 *		Purpose:		Save a tree structure to the specified file.
 */
void save_tree(FILE *file, TREE *node)
{
    static int level=0;
    register int i;

    fwrite(&(node->symbol), sizeof(BYTE2), 1, file);

libmegahal.c  view on Meta::CPAN

	goto fail;
    }

    fread(&(model->order), sizeof(BYTE1), 1, file);
    load_tree(file, model->forward);
    load_tree(file, model->backward);
    load_dictionary(file, model->dictionary);

    return(TRUE);
fail:
    fclose(file);

    return(FALSE);
}

/*---------------------------------------------------------------------------*/

/*
 *    Function:   Make_Words
 *
 *    Purpose:    Break a string into an array of words.
 */
void make_words(char *input, DICTIONARY *words)
{
    int offset=0;

    /*
     *		Clear the entries in the dictionary
     */
    free_dictionary(words);

    /*
     *		If the string is empty then do nothing, for it contains no words.
     */
    if(strlen(input)==0) return;

    /*
     *		Loop forever.
     */
    while(1) {

	/*
	 *		If the current character is of the same type as the previous
	 *		character, then include it in the word.  Otherwise, terminate
	 *		the current word.
	 */
	if(boundary(input, offset)) {
	    /*
	     *		Add the word to the dictionary
	     */
	    if(words->entry==NULL)
		words->entry=(STRING *)malloc((words->size+1)*sizeof(STRING));
	    else
		words->entry=(STRING *)realloc(words->entry, (words->size+1)*sizeof(STRING));

	    if(words->entry==NULL) {
		error("make_words", "Unable to reallocate dictionary");
		return;
	    }

	    words->entry[words->size].length=offset;
	    words->entry[words->size].word=input;
	    words->size+=1;

	    if(offset==(int)strlen(input)) break;
	    input+=offset;
	    offset=0;
	} else {
	    ++offset;
	}
    }

    /*
     *		If the last word isn't punctuation, then replace it with a
     *		full-stop character.
     */
    if(isalnum(words->entry[words->size-1].word[0])) {
	if(words->entry==NULL)
	    words->entry=(STRING *)malloc((words->size+1)*sizeof(STRING));
	else
	    words->entry=(STRING *)realloc(words->entry, (words->size+1)*sizeof(STRING));
	if(words->entry==NULL) {
	    error("make_words", "Unable to reallocate dictionary");
	    return;
	}

	words->entry[words->size].length=1;
	words->entry[words->size].word=".";
	++words->size;
    }
    else if(strchr("!.?", words->entry[words->size-1].word[words->entry[words->size-1].length-1])==NULL) {
	words->entry[words->size-1].length=1;
	words->entry[words->size-1].word=".";
    }

    return;
}

/*---------------------------------------------------------------------------*/
/*
 *		Function:	Boundary
 *
 *		Purpose:		Return whether or not a word boundary exists in a string
 *						at the specified location.
 */
bool boundary(char *string, int position)
{
    if(position==0)
	return(FALSE);

    if(position==(int)strlen(string))
	return(TRUE);

    if(
	(string[position]=='\'')&&
	(isalpha(string[position-1])!=0)&&
	(isalpha(string[position+1])!=0)
	)
	return(FALSE);

    if(
	(position>1)&&
	(string[position-1]=='\'')&&
	(isalpha(string[position-2])!=0)&&
	(isalpha(string[position])!=0)
	)
	return(FALSE);

    if(
	(isalpha(string[position])!=0)&&
	(isalpha(string[position-1])==0)
	)
	return(TRUE);

    if(
	(isalpha(string[position])==0)&&
	(isalpha(string[position-1])!=0)
	)
	return(TRUE);

    if(isdigit(string[position])!=isdigit(string[position-1]))
	return(TRUE);

    return(FALSE);
}

/*---------------------------------------------------------------------------*/
/*
 *		Function:	Make_Greeting
 *
 *		Purpose:		Put some special words into the dictionary so that the
 *						program will respond as if to a new judge.

libmegahal.c  view on Meta::CPAN

    int symbol;

    symbol=find_word(model->dictionary, word);
    if(symbol==0) return;
    if(isalnum(word.word[0])==0) return;
    symbol=find_word(aux, word);
    if(symbol==0) return;

    add_word(keys, word);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Reply
 *
 *		Purpose:		Generate a dictionary of reply words appropriate to the
 *						given dictionary of keywords.
 */
DICTIONARY *reply(MODEL *model, DICTIONARY *keys)
{
    static DICTIONARY *replies=NULL;
    register int i;
    int symbol;
    bool start=TRUE;

    if(replies==NULL) replies=new_dictionary();
    free_dictionary(replies);

    /*
     *		Start off by making sure that the model's context is empty.
     */
    initialize_context(model);
    model->context[0]=model->forward;
    used_key=FALSE;

    /*
     *		Generate the reply in the forward direction.
     */
    while(TRUE) {
	/*
	 *		Get a random symbol from the current context.
	 */
	if(start==TRUE) symbol=seed(model, keys);
	else symbol=babble(model, keys, replies);
	if((symbol==0)||(symbol==1)) break;
	start=FALSE;

	/*
	 *		Append the symbol to the reply dictionary.
	 */
	if(replies->entry==NULL)
	    replies->entry=(STRING *)malloc((replies->size+1)*sizeof(STRING));
	else
	    replies->entry=(STRING *)realloc(replies->entry, (replies->size+1)*sizeof(STRING));
	if(replies->entry==NULL) {
	    error("reply", "Unable to reallocate dictionary");
	    return(NULL);
	}

	replies->entry[replies->size].length=
	    model->dictionary->entry[symbol].length;
	replies->entry[replies->size].word=
	    model->dictionary->entry[symbol].word;
	replies->size+=1;

	/*
	 *		Extend the current context of the model with the current symbol.
	 */
	update_context(model, symbol);
    }

    /*
     *		Start off by making sure that the model's context is empty.
     */
    initialize_context(model);
    model->context[0]=model->backward;

    /*
     *		Re-create the context of the model from the current reply
     *		dictionary so that we can generate backwards to reach the
     *		beginning of the string.
     */
    if(replies->size>0) for(i=MIN(replies->size-1, model->order); i>=0; --i) {
	symbol=find_word(model->dictionary, replies->entry[i]);
	update_context(model, symbol);
    }

    /*
     *		Generate the reply in the backward direction.
     */
    while(TRUE) {
	/*
	 *		Get a random symbol from the current context.
	 */
	symbol=babble(model, keys, replies);
	if((symbol==0)||(symbol==1)) break;

	/*
	 *		Prepend the symbol to the reply dictionary.
	 */
	if(replies->entry==NULL)
	    replies->entry=(STRING *)malloc((replies->size+1)*sizeof(STRING));
	else
	    replies->entry=(STRING *)realloc(replies->entry, (replies->size+1)*sizeof(STRING));
	if(replies->entry==NULL) {
	    error("reply", "Unable to reallocate dictionary");
	    return(NULL);
	}

	/*
	 *		Shuffle everything up for the prepend.
	 */
	for(i=replies->size; i>0; --i) {
	    replies->entry[i].length=replies->entry[i-1].length;
	    replies->entry[i].word=replies->entry[i-1].word;
	}

	replies->entry[0].length=model->dictionary->entry[symbol].length;
	replies->entry[0].word=model->dictionary->entry[symbol].word;
	replies->size+=1;

	/*
	 *		Extend the current context of the model with the current symbol.
	 */
	update_context(model, symbol);
    }

    return(replies);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Evaluate_Reply
 *
 *		Purpose:		Measure the average surprise of keywords relative to the
 *						language model.
 */
float evaluate_reply(MODEL *model, DICTIONARY *keys, DICTIONARY *words)
{
    register int i;
    register int j;
    int symbol;
    float probability;
    int count;
    float entropy=(float)0.0;
    TREE *node;
    int num=0;

    if(words->size<=0) return((float)0.0);
    initialize_context(model);
    model->context[0]=model->forward;
    for(i=0; i<words->size; ++i) {
	symbol=find_word(model->dictionary, words->entry[i]);

	if(find_word(keys, words->entry[i])!=0) {
	    probability=(float)0.0;
	    count=0;
	    ++num;
	    for(j=0; j<model->order; ++j) if(model->context[j]!=NULL) {

		node=find_symbol(model->context[j], symbol);
		probability+=(float)(node->count)/
		    (float)(model->context[j]->usage);
		++count;

	    }

	    if(count>0.0) entropy-=(float)log(probability/(float)count);
	}

	update_context(model, symbol);
    }

    initialize_context(model);
    model->context[0]=model->backward;
    for(i=words->size-1; i>=0; --i) {
	symbol=find_word(model->dictionary, words->entry[i]);

	if(find_word(keys, words->entry[i])!=0) {
	    probability=(float)0.0;
	    count=0;
	    ++num;
	    for(j=0; j<model->order; ++j) if(model->context[j]!=NULL) {

		node=find_symbol(model->context[j], symbol);
		probability+=(float)(node->count)/
		    (float)(model->context[j]->usage);
		++count;

	    }

	    if(count>0.0) entropy-=(float)log(probability/(float)count);
	}

	update_context(model, symbol);
    }

    if(num>=8) entropy/=(float)sqrt(num-1);
    if(num>=16) entropy/=(float)num;

    return(entropy);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Make_Output
 *
 *		Purpose:		Generate a string from the dictionary of reply words.
 */
char *make_output(DICTIONARY *words)
{
    static char *output=NULL;
    register int i;
    register int j;
    int length;
    static char *output_none=NULL;

    if(output_none==NULL) output_none=malloc(40);

    if(output==NULL) {
	output=(char *)malloc(sizeof(char));
	if(output==NULL) {
	    error("make_output", "Unable to allocate output");
	    return(output_none);
	}
    }

    if(words->size==0) {
	if(output_none!=NULL)
	    strcpy(output_none, "I am utterly speechless!");
	return(output_none);
    }

    length=1;
    for(i=0; i<words->size; ++i) length+=words->entry[i].length;

    output=(char *)realloc(output, sizeof(char)*length);
    if(output==NULL) {
	error("make_output", "Unable to reallocate output.");
	if(output_none!=NULL)
	    strcpy(output_none, "I forgot what I was going to say!");
	return(output_none);
    }

    length=0;
    for(i=0; i<words->size; ++i)
	for(j=0; j<words->entry[i].length; ++j)
	    output[length++]=words->entry[i].word[j];

    output[length]='\0';

    return(output);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Babble
 *
 *		Purpose:		Return a random symbol from the current context, or a
 *						zero symbol identifier if we've reached either the
 *						start or end of the sentence.  Select the symbol based
 *						on probabilities, favouring keywords.  In all cases,
 *						use the longest available context to choose the symbol.
 */
int babble(MODEL *model, DICTIONARY *keys, DICTIONARY *words)
{
    TREE *node;
    register int i;
    int count;
    int symbol;

    /*
     *		Select the longest available context.
     */
    for(i=0; i<=model->order; ++i)
	if(model->context[i]!=NULL)
	    node=model->context[i];

    if(node->branch==0) return(0);

    /*
     *		Choose a symbol at random from this context.
     */
    i=rnd(node->branch);
    count=rnd(node->usage);
    while(count>=0) {
	/*
	 *		If the symbol occurs as a keyword, then use it.  Only use an
	 *		auxilliary keyword if a normal keyword has already been used.
	 */
	symbol=node->tree[i]->symbol;

	if(
	    (find_word(keys, model->dictionary->entry[symbol])!=0)&&
	    ((used_key==TRUE)||
	     (find_word(aux, model->dictionary->entry[symbol])==0))&&
	    (word_exists(words, model->dictionary->entry[symbol])==FALSE)
	    ) {
	    used_key=TRUE;
	    break;
	}
	count-=node->tree[i]->count;
	i=(i>=(node->branch-1))?0:i+1;
    }

    return(symbol);
}

/*---------------------------------------------------------------------------*/

libmegahal.c  view on Meta::CPAN

/*
 *		Function:	New_Swap
 *
 *		Purpose:		Allocate a new swap structure.
 */
SWAP *new_swap(void)
{
    SWAP *list;

    list=(SWAP *)malloc(sizeof(SWAP));
    if(list==NULL) {
	error("new_swap", "Unable to allocate swap");
	return(NULL);
    }
    list->size=0;
    list->from=NULL;
    list->to=NULL;

    return(list);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Add_Swap
 *
 *		Purpose:		Add a new entry to the swap structure.
 */
void add_swap(SWAP *list, char *s, char *d)
{
    list->size+=1;

    if(list->from==NULL) {
	list->from=(STRING *)malloc(sizeof(STRING));
	if(list->from==NULL) {
	    error("add_swap", "Unable to allocate list->from");
	    return;
	}
    }

    if(list->to==NULL) {
	list->to=(STRING *)malloc(sizeof(STRING));
	if(list->to==NULL) {
	    error("add_swap", "Unable to allocate list->to");
	    return;
	}
    }

    list->from=(STRING *)realloc(list->from, sizeof(STRING)*(list->size));
    if(list->from==NULL) {
	error("add_swap", "Unable to reallocate from");
	return;
    }

    list->to=(STRING *)realloc(list->to, sizeof(STRING)*(list->size));
    if(list->to==NULL) {
	error("add_swap", "Unable to reallocate to");
	return;
    }

    list->from[list->size-1].length=strlen(s);
    list->from[list->size-1].word=strdup(s);
    list->to[list->size-1].length=strlen(d);
    list->to[list->size-1].word=strdup(d);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Initialize_Swap
 *
 *		Purpose:		Read a swap structure from a file.
 */
SWAP *initialize_swap(char *filename)
{
    SWAP *list;
    FILE *file=NULL;
    char buffer[1024];
    char *from;
    char *to;

    list=new_swap();

    if(filename==NULL) return(list);

    file=fopen(filename, "r");
    if(file==NULL) return(list);

    while(!feof(file)) {

	if(fgets(buffer, 1024, file)==NULL) break;
	if(buffer[0]=='#') continue;
	from=strtok(buffer, "\t ");
	to=strtok(NULL, "\t \n#");

	add_swap(list, from, to);
    }

    fclose(file);
    return(list);
}

/*---------------------------------------------------------------------------*/

void free_swap(SWAP *swap)
{
    register int i;

    if(swap==NULL) return;

    for(i=0; i<swap->size; ++i) {
	free_word(swap->from[i]);
	free_word(swap->to[i]);
    }
    free(swap->from);
    free(swap->to);
    free(swap);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Initialize_List
 *
 *		Purpose:		Read a dictionary from a file.
 */
DICTIONARY *initialize_list(char *filename)
{
    DICTIONARY *list;
    FILE *file=NULL;
    STRING word;
    char *string;
    char buffer[1024];

    list=new_dictionary();

    if(filename==NULL) return(list);

    file=fopen(filename, "r");
    if(file==NULL) return(list);

    while(!feof(file)) {

	if(fgets(buffer, 1024, file)==NULL) break;
	if(buffer[0]=='#') continue;
	string=strtok(buffer, "\t \n#");

	if((string!=NULL)&&(strlen(string)>0)) {
	    word.length=strlen(string);
	    word.word=strdup(buffer);
	    add_word(list, word);
	}
    }

    fclose(file);
    return(list);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Delay
 *
 *		Purpose:		Display the string to stdout as if it was typed by a human.
 */
void delay(char *string)
{
    register int i;

    /*
     *		Don't simulate typing if the feature is turned off
     */
    if(typing_delay==FALSE)	{
	fprintf(stdout, string);
	return;
    }

    /*
     *		Display the entire string, one character at a time
     */
    for(i=0; i<(int)strlen(string)-1; ++i) typein(string[i]);
    usleep((D_THINK+rnd(V_THINK)-rnd(V_THINK))/2);
    typein(string[i]);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Typein
 *
 *		Purpose:		Display a character to stdout as if it was typed by a human.
 */
void typein(char c)
{
    /*
     *		Standard keyboard delay
     */
    usleep(D_KEY+rnd(V_KEY)-rnd(V_KEY));
    fprintf(stdout, "%c", c);
    fflush(stdout);

    /*
     *		A random thinking delay
     */
    if((!isalnum(c))&&((rnd(100))<P_THINK))
	usleep(D_THINK+rnd(V_THINK)-rnd(V_THINK));
}

/*---------------------------------------------------------------------------*/

libmegahal.c  view on Meta::CPAN

    free_model(*model);
    free_words(ban);
    free_dictionary(ban);
    free_words(aux);
    free_dictionary(aux);
    free_words(grt);
    free_dictionary(grt);
    free_swap(swp);

    /*
     *		Create a language model.
     */
    *model=new_model(order);

    /*
     *		Train the model on a text if one exists
     */

    sprintf(filename, "%s%smegahal.brn", directory, SEP);
    if(load_model(filename, *model)==FALSE) {
	sprintf(filename, "%s%smegahal.trn", directory, SEP);
	train(*model, filename);
    }

    /*
     *		Read a dictionary containing banned keywords, auxiliary keywords,
     *		greeting keywords and swap keywords
     */
    sprintf(filename, "%s%smegahal.ban", directory, SEP);
    ban=initialize_list(filename);
    sprintf(filename, "%s%smegahal.aux", directory, SEP);
    aux=initialize_list(filename);
    sprintf(filename, "%s%smegahal.grt", directory, SEP);
    grt=initialize_list(filename);
    sprintf(filename, "%s%smegahal.swp", directory, SEP);
    swp=initialize_swap(filename);
}

/*---------------------------------------------------------------------------*/

void change_personality(DICTIONARY *command, int position, MODEL **model)
{

    if(directory == NULL) {
	directory = (char *)malloc(sizeof(char)*(strlen(DEFAULT)+1));
	if(directory == NULL) {
	    error("change_personality", "Unable to allocate directory");
	} else {
	    strcpy(directory, DEFAULT);
	}
    }

    if(last == NULL) {
	last = strdup(directory);
    }

    if((command == NULL)||((position+2)>=command->size)) {
	/* no dir set, so we leave it to whatever was set above */
    } else {
        directory=(char *)realloc(directory,
                                  sizeof(char)*(command->entry[position+2].length+1));
        if(directory == NULL)
            error("change_personality", "Unable to allocate directory");
        strncpy(directory, command->entry[position+2].word,
                command->entry[position+2].length);
        directory[command->entry[position+2].length]='\0';
    }

    load_personality(model);
}

/*---------------------------------------------------------------------------*/

void free_words(DICTIONARY *words)
{
    unsigned int i;

    if(words == NULL) return;

    if(words->entry != NULL)
	for(i=0; i<words->size; ++i) free_word(words->entry[i]);
}

/*---------------------------------------------------------------------------*/

void free_word(STRING word)
{
    free(word.word);
}

/*===========================================================================*/

/*
 *		$Log: megahal.c,v $
 *		Revision 1.6  2002/10/16 04:32:53  davidw
 *		* megahal.c (change_personality): [ 541667 ] Added patch from Andrew
 *		  Burke to rework logic in change_personality.
 *
 *		* megahal.c: Trailing white space cleanup.
 *
 *		* python-interface.c: [ 546397 ] Change python include path to a more
 *		  recent version.  This should really be fixed by using some of
 *		  Python's build automation tools.
 *
 *		Revision 1.5  2000/11/08 11:07:11  davidw
 *		Moved README to docs directory.
 *
 *		Changes to debian files.
 *
 *		Revision 1.4  2000/09/07 21:51:12  davidw
 *		Created some library functions that I think are workable, and moved
 *		everything else into megahal.c as static variables/functions.
 *
 *		Revision 1.3  2000/09/07 11:43:43  davidw
 *		Started hacking:
 *
 *		Reduced makefile targets, eliminating non-Linux OS's.  There should be
 *		a cleaner way to do this.
 *
 *		Added Tcl and Python C level interfaces.
 *
 *		Revision 1.23  1998/05/19 03:02:02  hutch
 *		Removed a small malloc() bug, and added a progress display for
 *		generate_reply().
 *
 *		Revision 1.22  1998/04/24 03:47:03  hutch



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