[fio.git] / exp / expression-parser.y

%{

/*
 * (C) Copyright 2014, Stephen M. Cameron.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  published by the Free Software Foundation.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 */

#include <stdio.h>
#include <string.h>
#include <math.h>

struct parser_value_type {
	double dval;
	long long ival;
	int has_dval;
	int has_error;
};

typedef union valtype {
	struct parser_value_type v;
} PARSER_VALUE_TYPE;

#define YYSTYPE PARSER_VALUE_TYPE

int yyerror(__attribute__((unused)) long long *result,
		__attribute__((unused)) double *dresult,
		__attribute__((unused)) int *has_error,
		__attribute__((unused)) int *units_specified,
		__attribute__((unused)) const char *msg);

extern int yylex(void);
extern void yyrestart(FILE *file);
extern int lexer_value_is_time;

%}

%union valtype {
	struct parser_value_type {
		double dval;
		long long ival;
		int has_dval;
		int has_error;
	} v;
};

%token <v> NUMBER
%token <v> BYE
%token <v> SUFFIX 
%left '-' '+'
%right SUFFIX
%left '*' '/'
%right '^'
%left '%'
%nonassoc UMINUS
%parse-param { long long *result }
%parse-param { double *dresult }
%parse-param { int *has_error }
%parse-param { int *units_specified }

%type <v> expression
%%

top_level:	expression {
				*result = $1.ival;
				*dresult = $1.dval;
				*has_error = $1.has_error;
			}
		| expression error {
				*result = $1.ival;
				*dresult = $1.dval;
				*has_error = 1;
			}
expression:	expression '+' expression { 
			if (!$1.has_dval && !$3.has_dval)
				$$.ival = $1.ival + $3.ival;
			else
				$$.ival = (long long) ($1.dval + $3.dval);
			$$.dval = $1.dval + $3.dval;
			$$.has_error = $1.has_error || $3.has_error;
		}
	|	expression '-' expression {
			if (!$1.has_dval && !$3.has_dval)
				$$.ival = $1.ival - $3.ival; 
			else
				$$.ival = (long long) ($1.dval - $3.dval); 
			$$.dval = $1.dval - $3.dval; 
			$$.has_error = $1.has_error || $3.has_error;
		}
	|	expression '*' expression {
			if (!$1.has_dval && !$3.has_dval)
				$$.ival = $1.ival * $3.ival;
			else
				$$.ival = (long long) ($1.dval * $3.dval);
			$$.dval = $1.dval * $3.dval;
			$$.has_error = $1.has_error || $3.has_error;
		}
	|	expression '/' expression {
			if ($3.ival == 0)
				yyerror(0, 0, 0, 0, "divide by zero");
			else
				$$.ival = $1.ival / $3.ival;
			if ($3.dval < 1e-20 && $3.dval > -1e-20)
				yyerror(0, 0, 0, 0, "divide by zero");
			else
				$$.dval = $1.dval / $3.dval;
			if ($3.has_dval || $1.has_dval)
				$$.ival = (long long) $$.dval;
			$$.has_error = $1.has_error || $3.has_error;
		}
	|	'-' expression %prec UMINUS {
			$$.ival = -$2.ival;
			$$.dval = -$2.dval;
			$$.has_error = $2.has_error;
		}
	|	'(' expression ')' { $$ = $2; }
	|	expression SUFFIX {
			if (!$1.has_dval && !$2.has_dval)
				$$.ival = $1.ival * $2.ival;
			else
				$$.ival = (long long) $1.dval * $2.dval;
			if ($1.has_dval || $2.has_dval)
				$$.dval = $1.dval * $2.dval;
			else
				$$.dval = $1.ival * $2.ival;
			$$.has_error = $1.has_error || $2.has_error;
			*units_specified = 1;
		}
	|	expression '%' expression {
			if ($1.has_dval || $3.has_dval)
				yyerror(0, 0, 0, 0, "modulo on floats");
			if ($3.ival == 0)
				yyerror(0, 0, 0, 0, "divide by zero");
			else {
				$$.ival = $1.ival % $3.ival;
				$$.dval = $$.ival;
			}
			$$.has_error = $1.has_error || $3.has_error;
		}
	|	expression '^' expression {
			$$.has_error = $1.has_error || $3.has_error;
			if (!$1.has_dval && !$3.has_dval) {
				int i;

				if ($3.ival == 0) {
					$$.ival = 1;
				} else if ($3.ival > 0) {
					long long tmp = $1.ival;
					$$.ival = 1.0;
					for (i = 0; i < $3.ival; i++)
						$$.ival *= tmp;
				}  else {
					/* integers, 2^-3, ok, we now have doubles */
					double tmp;
					if ($1.ival == 0 && $3.ival == 0) {
						tmp = 1.0;
						$$.has_error = 1;
					} else {
						double x = (double) $1.ival;
						double y = (double) $3.ival;
						tmp = pow(x, y);
					}
					$$.ival = (long long) tmp;
				}
				$$.dval = pow($1.dval, $3.dval);
			} else {
				$$.dval = pow($1.dval, $3.dval);
				$$.ival = (long long) $$.dval;
			}
		}
	|	NUMBER { $$ = $1; };
%%
#include <stdio.h>

/* Urgh.  yacc and lex are kind of horrible.  This is not thread safe, obviously. */
static int lexer_read_offset = 0;
static char lexer_input_buffer[1000];

int lexer_input(char* buffer, unsigned int *bytes_read, int bytes_requested)
{
	int bytes_left = strlen(lexer_input_buffer) - lexer_read_offset;

	if (bytes_requested > bytes_left )
		bytes_requested = bytes_left;
	memcpy(buffer, &lexer_input_buffer[lexer_read_offset], bytes_requested);
	*bytes_read = bytes_requested;
	lexer_read_offset += bytes_requested;
	return 0;
}

static void setup_to_parse_string(const char *string)
{
	unsigned int len;

	len = sizeof(lexer_input_buffer) - 3;
	if (len > strlen(string))
		len = strlen(string);

	strncpy(lexer_input_buffer, string, len);
	lexer_input_buffer[len] = '\0'; 
	lexer_input_buffer[len + 1] = '\0';  /* lex/yacc want string double null terminated! */
	lexer_read_offset = 0;
}

int evaluate_arithmetic_expression(const char *buffer, long long *ival, double *dval,
					double implied_units, int is_time)
{
	int rc, units_specified = 0, has_error = 0;

	lexer_value_is_time = is_time;
	setup_to_parse_string(buffer);
	rc = yyparse(ival, dval, &has_error, &units_specified);
	yyrestart(NULL);
	if (rc || has_error) {
		*ival = 0;
		*dval = 0;
		has_error = 1;
	}
	if (!units_specified) {
		*ival = (int) ((double) *ival * implied_units);
		*dval = *dval * implied_units;
	}
	return has_error;
}

int yyerror(__attribute__((unused)) long long *result,
		__attribute__((unused)) double *dresult,
		__attribute__((unused)) int *has_error,
		__attribute__((unused)) int *units_specified,
		__attribute__((unused)) const char *msg)
{
	/* We do not need to do anything here. */
	return 0;
}
Commit	Line	Data
	1	%{
	2
	3	/*
	4	* (C) Copyright 2014, Stephen M. Cameron.
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License version 2 as
	8	* published by the Free Software Foundation.
	9	*
	10	* This program is distributed in the hope that it will be useful,
	11	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	* GNU General Public License for more details.
	14	*
	15	* You should have received a copy of the GNU General Public License
	16	* along with this program; if not, write to the Free Software
	17	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
	18	*
	19	*/
	20
	21	#include <stdio.h>
	22	#include <string.h>
	23	#include <math.h>
	24
	25	struct parser_value_type {
	26	double dval;
	27	long long ival;
	28	int has_dval;
	29	int has_error;
	30	};
	31
	32	typedef union valtype {
	33	struct parser_value_type v;
	34	} PARSER_VALUE_TYPE;
	35
	36	#define YYSTYPE PARSER_VALUE_TYPE
	37
	38	int yyerror(__attribute__((unused)) long long *result,
	39	__attribute__((unused)) double *dresult,
	40	__attribute__((unused)) int *has_error,
	41	__attribute__((unused)) int *units_specified,
	42	__attribute__((unused)) const char *msg);
	43
	44	extern int yylex(void);
	45	extern void yyrestart(FILE *file);
	46	extern int lexer_value_is_time;
	47
	48	%}
	49
	50	%union valtype {
	51	struct parser_value_type {
	52	double dval;
	53	long long ival;
	54	int has_dval;
	55	int has_error;
	56	} v;
	57	};
	58
	59	%token <v> NUMBER
	60	%token <v> BYE
	61	%token <v> SUFFIX
	62	%left '-' '+'
	63	%right SUFFIX
	64	%left '*' '/'
	65	%right '^'
	66	%left '%'
	67	%nonassoc UMINUS
	68	%parse-param { long long *result }
	69	%parse-param { double *dresult }
	70	%parse-param { int *has_error }
	71	%parse-param { int *units_specified }
	72
	73	%type <v> expression
	74	%%
	75
	76	top_level: expression {
	77	*result = $1.ival;
	78	*dresult = $1.dval;
	79	*has_error = $1.has_error;
	80	}
	81	\| expression error {
	82	*result = $1.ival;
	83	*dresult = $1.dval;
	84	*has_error = 1;
	85	}
	86	expression: expression '+' expression {
	87	if (!$1.has_dval && !$3.has_dval)
	88	$$.ival = $1.ival + $3.ival;
	89	else
	90	$$.ival = (long long) ($1.dval + $3.dval);
	91	$$.dval = $1.dval + $3.dval;
	92	$$.has_error = $1.has_error \|\| $3.has_error;
	93	}
	94	\| expression '-' expression {
	95	if (!$1.has_dval && !$3.has_dval)
	96	$$.ival = $1.ival - $3.ival;
	97	else
	98	$$.ival = (long long) ($1.dval - $3.dval);
	99	$$.dval = $1.dval - $3.dval;
	100	$$.has_error = $1.has_error \|\| $3.has_error;
	101	}
	102	\| expression '*' expression {
	103	if (!$1.has_dval && !$3.has_dval)
	104	$$.ival = $1.ival * $3.ival;
	105	else
	106	$$.ival = (long long) ($1.dval * $3.dval);
	107	$$.dval = $1.dval * $3.dval;
	108	$$.has_error = $1.has_error \|\| $3.has_error;
	109	}
	110	\| expression '/' expression {
	111	if ($3.ival == 0)
	112	yyerror(0, 0, 0, 0, "divide by zero");
	113	else
	114	$$.ival = $1.ival / $3.ival;
	115	if ($3.dval < 1e-20 && $3.dval > -1e-20)
	116	yyerror(0, 0, 0, 0, "divide by zero");
	117	else
	118	$$.dval = $1.dval / $3.dval;
	119	if ($3.has_dval \|\| $1.has_dval)
	120	$$.ival = (long long) $$.dval;
	121	$$.has_error = $1.has_error \|\| $3.has_error;
	122	}
	123	\| '-' expression %prec UMINUS {
	124	$$.ival = -$2.ival;
	125	$$.dval = -$2.dval;
	126	$$.has_error = $2.has_error;
	127	}
	128	\| '(' expression ')' { $$ = $2; }
	129	\| expression SUFFIX {
	130	if (!$1.has_dval && !$2.has_dval)
	131	$$.ival = $1.ival * $2.ival;
	132	else
	133	$$.ival = (long long) $1.dval * $2.dval;
	134	if ($1.has_dval \|\| $2.has_dval)
	135	$$.dval = $1.dval * $2.dval;
	136	else
	137	$$.dval = $1.ival * $2.ival;
	138	$$.has_error = $1.has_error \|\| $2.has_error;
	139	*units_specified = 1;
	140	}
	141	\| expression '%' expression {
	142	if ($1.has_dval \|\| $3.has_dval)
	143	yyerror(0, 0, 0, 0, "modulo on floats");
	144	if ($3.ival == 0)
	145	yyerror(0, 0, 0, 0, "divide by zero");
	146	else {
	147	$$.ival = $1.ival % $3.ival;
	148	$$.dval = $$.ival;
	149	}
	150	$$.has_error = $1.has_error \|\| $3.has_error;
	151	}
	152	\| expression '^' expression {
	153	$$.has_error = $1.has_error \|\| $3.has_error;
	154	if (!$1.has_dval && !$3.has_dval) {
	155	int i;
	156
	157	if ($3.ival == 0) {
	158	$$.ival = 1;
	159	} else if ($3.ival > 0) {
	160	long long tmp = $1.ival;
	161	$$.ival = 1.0;
	162	for (i = 0; i < $3.ival; i++)
	163	$$.ival *= tmp;
	164	} else {
	165	/* integers, 2^-3, ok, we now have doubles */
	166	double tmp;
	167	if ($1.ival == 0 && $3.ival == 0) {
	168	tmp = 1.0;
	169	$$.has_error = 1;
	170	} else {
	171	double x = (double) $1.ival;
	172	double y = (double) $3.ival;
	173	tmp = pow(x, y);
	174	}
	175	$$.ival = (long long) tmp;
	176	}
	177	$$.dval = pow($1.dval, $3.dval);
	178	} else {
	179	$$.dval = pow($1.dval, $3.dval);
	180	$$.ival = (long long) $$.dval;
	181	}
	182	}
	183	\| NUMBER { $$ = $1; };
	184	%%
	185	#include <stdio.h>
	186
	187	/* Urgh. yacc and lex are kind of horrible. This is not thread safe, obviously. */
	188	static int lexer_read_offset = 0;
	189	static char lexer_input_buffer[1000];
	190
	191	int lexer_input(char* buffer, unsigned int *bytes_read, int bytes_requested)
	192	{
	193	int bytes_left = strlen(lexer_input_buffer) - lexer_read_offset;
	194
	195	if (bytes_requested > bytes_left )
	196	bytes_requested = bytes_left;
	197	memcpy(buffer, &lexer_input_buffer[lexer_read_offset], bytes_requested);
	198	*bytes_read = bytes_requested;
	199	lexer_read_offset += bytes_requested;
	200	return 0;
	201	}
	202
	203	static void setup_to_parse_string(const char *string)
	204	{
	205	unsigned int len;
	206
	207	len = sizeof(lexer_input_buffer) - 3;
	208	if (len > strlen(string))
	209	len = strlen(string);
	210
	211	strncpy(lexer_input_buffer, string, len);
	212	lexer_input_buffer[len] = '\0';
	213	lexer_input_buffer[len + 1] = '\0'; /* lex/yacc want string double null terminated! */
	214	lexer_read_offset = 0;
	215	}
	216
	217	int evaluate_arithmetic_expression(const char buffer, long long ival, double *dval,
	218	double implied_units, int is_time)
	219	{
	220	int rc, units_specified = 0, has_error = 0;
	221
	222	lexer_value_is_time = is_time;
	223	setup_to_parse_string(buffer);
	224	rc = yyparse(ival, dval, &has_error, &units_specified);
	225	yyrestart(NULL);
	226	if (rc \|\| has_error) {
	227	*ival = 0;
	228	*dval = 0;
	229	has_error = 1;
	230	}
	231	if (!units_specified) {
	232	ival = (int) ((double) ival * implied_units);
	233	dval = dval * implied_units;
	234	}
	235	return has_error;
	236	}
	237
	238	int yyerror(__attribute__((unused)) long long *result,
	239	__attribute__((unused)) double *dresult,
	240	__attribute__((unused)) int *has_error,
	241	__attribute__((unused)) int *units_specified,
	242	__attribute__((unused)) const char *msg)
	243	{
	244	/* We do not need to do anything here. */
	245	return 0;
	246	}
	247