[lttng-tools.git] / src / lib / lttng-ctl / filter / filter-parser.y

%{
/*
 * filter-parser.y
 *
 * LTTng filter expression parser
 *
 * Copyright 2012 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License, version 2.1 only,
 * as published by the Free Software Foundation.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this library; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 *
 * Grammar inspired from http://www.quut.com/c/ANSI-C-grammar-y.html
 */

#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <errno.h>
#include <inttypes.h>
#include "filter-ast.h"
#include "filter-parser.h"

#include <common/macros.h>

#define WIDTH_u64_SCANF_IS_A_BROKEN_API	"20"
#define WIDTH_o64_SCANF_IS_A_BROKEN_API	"22"
#define WIDTH_x64_SCANF_IS_A_BROKEN_API	"17"
#define WIDTH_lg_SCANF_IS_A_BROKEN_API	"4096"	/* Hugely optimistic approximation */

LTTNG_HIDDEN
int yydebug;
LTTNG_HIDDEN
int filter_parser_debug = 0;

LTTNG_HIDDEN
int yyparse(struct filter_parser_ctx *parser_ctx, yyscan_t scanner);
LTTNG_HIDDEN
int yylex(union YYSTYPE *yyval, yyscan_t scanner);
LTTNG_HIDDEN
int yylex_init_extra(struct filter_parser_ctx *parser_ctx, yyscan_t * ptr_yy_globals);
LTTNG_HIDDEN
int yylex_destroy(yyscan_t yyparser_ctx);
LTTNG_HIDDEN
void yyrestart(FILE * in_str, yyscan_t parser_ctx);

struct gc_string {
	struct cds_list_head gc;
	size_t alloclen;
	char s[];
};

static const char *node_type_to_str[] = {
	[ NODE_UNKNOWN ] = "NODE_UNKNOWN",
	[ NODE_ROOT ] = "NODE_ROOT",
	[ NODE_EXPRESSION ] = "NODE_EXPRESSION",
	[ NODE_OP ] = "NODE_OP",
	[ NODE_UNARY_OP ] = "NODE_UNARY_OP",
};

LTTNG_HIDDEN
const char *node_type(struct filter_node *node)
{
	if (node->type < NR_NODE_TYPES)
		return node_type_to_str[node->type];
	else
		return NULL;
}

static struct gc_string *gc_string_alloc(struct filter_parser_ctx *parser_ctx,
					 size_t len)
{
	struct gc_string *gstr;
	size_t alloclen;

	/* TODO: could be faster with find first bit or glib Gstring */
	/* sizeof long to account for malloc header (int or long ?) */
	for (alloclen = 8; alloclen < sizeof(long) + sizeof(*gstr) + len;
	     alloclen *= 2);

	gstr = malloc(alloclen);
	cds_list_add(&gstr->gc, &parser_ctx->allocated_strings);
	gstr->alloclen = alloclen;
	return gstr;
}

/*
 * note: never use gc_string_append on a string that has external references.
 * gsrc will be garbage collected immediately, and gstr might be.
 * Should only be used to append characters to a string literal or constant.
 */
LTTNG_HIDDEN
struct gc_string *gc_string_append(struct filter_parser_ctx *parser_ctx,
				   struct gc_string *gstr,
				   struct gc_string *gsrc)
{
	size_t newlen = strlen(gsrc->s) + strlen(gstr->s) + 1;
	size_t alloclen;

	/* TODO: could be faster with find first bit or glib Gstring */
	/* sizeof long to account for malloc header (int or long ?) */
	for (alloclen = 8; alloclen < sizeof(long) + sizeof(*gstr) + newlen;
	     alloclen *= 2);

	if (alloclen > gstr->alloclen) {
		struct gc_string *newgstr;

		newgstr = gc_string_alloc(parser_ctx, newlen);
		strcpy(newgstr->s, gstr->s);
		strcat(newgstr->s, gsrc->s);
		cds_list_del(&gstr->gc);
		free(gstr);
		gstr = newgstr;
	} else {
		strcat(gstr->s, gsrc->s);
	}
	cds_list_del(&gsrc->gc);
	free(gsrc);
	return gstr;
}

LTTNG_HIDDEN
void setstring(struct filter_parser_ctx *parser_ctx, YYSTYPE *lvalp, const char *src)
{
	lvalp->gs = gc_string_alloc(parser_ctx, strlen(src) + 1);
	strcpy(lvalp->gs->s, src);
}

static struct filter_node *make_node(struct filter_parser_ctx *scanner,
				  enum node_type type)
{
	struct filter_ast *ast = filter_parser_get_ast(scanner);
	struct filter_node *node;

	node = malloc(sizeof(*node));
	if (!node)
		return NULL;
	memset(node, 0, sizeof(*node));
	node->type = type;
	cds_list_add(&node->gc, &ast->allocated_nodes);

	switch (type) {
	case NODE_ROOT:
		fprintf(stderr, "[error] %s: trying to create root node\n", __func__);
		break;

	case NODE_EXPRESSION:
		break;
	case NODE_OP:
		break;
	case NODE_UNARY_OP:
		break;

	case NODE_UNKNOWN:
	default:
		fprintf(stderr, "[error] %s: unknown node type %d\n", __func__,
			(int) type);
		break;
	}

	return node;
}

static struct filter_node *make_op_node(struct filter_parser_ctx *scanner,
			enum op_type type,
			struct filter_node *lchild,
			struct filter_node *rchild)
{
	struct filter_ast *ast = filter_parser_get_ast(scanner);
	struct filter_node *node;

	node = malloc(sizeof(*node));
	if (!node)
		return NULL;
	memset(node, 0, sizeof(*node));
	node->type = NODE_OP;
	cds_list_add(&node->gc, &ast->allocated_nodes);
	node->u.op.type = type;
	node->u.op.lchild = lchild;
	node->u.op.rchild = rchild;
	return node;
}

LTTNG_HIDDEN
void yyerror(struct filter_parser_ctx *parser_ctx, yyscan_t scanner, const char *str)
{
	fprintf(stderr, "error %s\n", str);
}
 
LTTNG_HIDDEN
int yywrap(void)
{
	return 1;
} 

#define parse_error(parser_ctx, str)				\
do {								\
	yyerror(parser_ctx, parser_ctx->scanner, YY_("parse error: " str "\n"));	\
	YYERROR;						\
} while (0)

static void free_strings(struct cds_list_head *list)
{
	struct gc_string *gstr, *tmp;

	cds_list_for_each_entry_safe(gstr, tmp, list, gc)
		free(gstr);
}

static struct filter_ast *filter_ast_alloc(void)
{
	struct filter_ast *ast;

	ast = malloc(sizeof(*ast));
	if (!ast)
		return NULL;
	memset(ast, 0, sizeof(*ast));
	CDS_INIT_LIST_HEAD(&ast->allocated_nodes);
	ast->root.type = NODE_ROOT;
	return ast;
}

static void filter_ast_free(struct filter_ast *ast)
{
	struct filter_node *node, *tmp;

	cds_list_for_each_entry_safe(node, tmp, &ast->allocated_nodes, gc)
		free(node);
	free(ast);
}

LTTNG_HIDDEN
int filter_parser_ctx_append_ast(struct filter_parser_ctx *parser_ctx)
{
	return yyparse(parser_ctx, parser_ctx->scanner);
}

LTTNG_HIDDEN
struct filter_parser_ctx *filter_parser_ctx_alloc(FILE *input)
{
	struct filter_parser_ctx *parser_ctx;
	int ret;

	yydebug = filter_parser_debug;

	parser_ctx = malloc(sizeof(*parser_ctx));
	if (!parser_ctx)
		return NULL;
	memset(parser_ctx, 0, sizeof(*parser_ctx));

	ret = yylex_init_extra(parser_ctx, &parser_ctx->scanner);
	if (ret) {
		fprintf(stderr, "yylex_init error\n");
		goto cleanup_parser_ctx;
	}
	/* Start processing new stream */
	yyrestart(input, parser_ctx->scanner);

	parser_ctx->ast = filter_ast_alloc();
	if (!parser_ctx->ast)
		goto cleanup_lexer;
	CDS_INIT_LIST_HEAD(&parser_ctx->allocated_strings);

	if (yydebug)
		fprintf(stdout, "parser_ctx input is a%s.\n",
			isatty(fileno(input)) ? "n interactive tty" :
						" noninteractive file");

	return parser_ctx;

cleanup_lexer:
	ret = yylex_destroy(parser_ctx->scanner);
	if (!ret)
		fprintf(stderr, "yylex_destroy error\n");
cleanup_parser_ctx:
	free(parser_ctx);
	return NULL;
}

LTTNG_HIDDEN
void filter_parser_ctx_free(struct filter_parser_ctx *parser_ctx)
{
	int ret;

	free_strings(&parser_ctx->allocated_strings);
	filter_ast_free(parser_ctx->ast);
	ret = yylex_destroy(parser_ctx->scanner);
	if (ret)
		fprintf(stderr, "yylex_destroy error\n");
	free(parser_ctx);
}

%}

%define api.pure
	/* %locations */
%parse-param {struct filter_parser_ctx *parser_ctx}
%parse-param {yyscan_t scanner}
%lex-param {yyscan_t scanner}
%start translation_unit
%token CHARACTER_CONSTANT_START SQUOTE STRING_LITERAL_START DQUOTE
%token ESCSEQ CHAR_STRING_TOKEN
%token DECIMAL_CONSTANT OCTAL_CONSTANT HEXADECIMAL_CONSTANT FLOAT_CONSTANT
%token LSBRAC RSBRAC LPAREN RPAREN LBRAC RBRAC RARROW
%token STAR PLUS MINUS
%token MOD_OP DIV_OP RIGHT_OP LEFT_OP
%token EQ_OP NE_OP LE_OP GE_OP LT_OP GT_OP AND_OP OR_OP NOT_OP
%token ASSIGN COLON SEMICOLON DOTDOTDOT DOT EQUAL COMMA
%token XOR_BIN AND_BIN OR_BIN NOT_BIN

%token <gs> IDENTIFIER GLOBAL_IDENTIFIER
%token ERROR
%union
{
	long long ll;
	char c;
	struct gc_string *gs;
	struct filter_node *n;
}

%type <gs> s_char s_char_sequence c_char c_char_sequence

%type <n> primary_expression
%type <n> postfix_expression
%type <n> unary_expression
%type <n> unary_operator
%type <n> multiplicative_expression
%type <n> additive_expression
%type <n> shift_expression
%type <n> relational_expression
%type <n> equality_expression
%type <n> and_expression
%type <n> exclusive_or_expression
%type <n> inclusive_or_expression
%type <n> logical_and_expression
%type <n> logical_or_expression
%type <n> expression

%%


/* 1.5 Constants */

c_char_sequence:
		c_char
		{	$$ = $1;					}
	|	c_char_sequence c_char
		{	$$ = gc_string_append(parser_ctx, $1, $2);		}
	;

c_char:
		CHAR_STRING_TOKEN
		{	$$ = yylval.gs;					}
	|	ESCSEQ
		{
			parse_error(parser_ctx, "escape sequences not supported yet");
		}
	;

/* 1.6 String literals */

s_char_sequence:
		s_char
		{	$$ = $1;					}
	|	s_char_sequence s_char
		{	$$ = gc_string_append(parser_ctx, $1, $2);		}
	;

s_char:
		CHAR_STRING_TOKEN
		{	$$ = yylval.gs;					}
	|	ESCSEQ
		{
			parse_error(parser_ctx, "escape sequences not supported yet");
		}
	;

primary_expression
	:	IDENTIFIER
		{
			$$ = make_node(parser_ctx, NODE_EXPRESSION);
			$$->u.expression.type = AST_EXP_IDENTIFIER;
			$$->u.expression.u.identifier = yylval.gs->s;
		}
	|	GLOBAL_IDENTIFIER
		{
			$$ = make_node(parser_ctx, NODE_EXPRESSION);
			$$->u.expression.type = AST_EXP_GLOBAL_IDENTIFIER;
			$$->u.expression.u.identifier = yylval.gs->s;
		}

	|	DECIMAL_CONSTANT
		{
			$$ = make_node(parser_ctx, NODE_EXPRESSION);
			$$->u.expression.type = AST_EXP_CONSTANT;
			if (sscanf(yylval.gs->s, "%" WIDTH_u64_SCANF_IS_A_BROKEN_API SCNu64,
					&$$->u.expression.u.constant) != 1) {
				parse_error(parser_ctx, "cannot scanf decimal constant");
			}
		}
	|	OCTAL_CONSTANT
		{
			$$ = make_node(parser_ctx, NODE_EXPRESSION);
			$$->u.expression.type = AST_EXP_CONSTANT;
			if (!strcmp(yylval.gs->s, "0")) {
				$$->u.expression.u.constant = 0;
			} else if (sscanf(yylval.gs->s, "0%" WIDTH_o64_SCANF_IS_A_BROKEN_API SCNo64,
					&$$->u.expression.u.constant) != 1) {
				parse_error(parser_ctx, "cannot scanf octal constant");
			}
		}
	|	HEXADECIMAL_CONSTANT
		{
			$$ = make_node(parser_ctx, NODE_EXPRESSION);
			$$->u.expression.type = AST_EXP_CONSTANT;
			if (sscanf(yylval.gs->s, "0x%" WIDTH_x64_SCANF_IS_A_BROKEN_API SCNx64,
					&$$->u.expression.u.constant) != 1) {
				parse_error(parser_ctx, "cannot scanf hexadecimal constant");
			}
		}
	|	FLOAT_CONSTANT
		{
			$$ = make_node(parser_ctx, NODE_EXPRESSION);
			$$->u.expression.type = AST_EXP_FLOAT_CONSTANT;
			if (sscanf(yylval.gs->s, "%" WIDTH_lg_SCANF_IS_A_BROKEN_API "lg",
					&$$->u.expression.u.float_constant) != 1) {
				parse_error(parser_ctx, "cannot scanf float constant");
			}
		}
	|	STRING_LITERAL_START DQUOTE
		{
			$$ = make_node(parser_ctx, NODE_EXPRESSION);
			$$->u.expression.type = AST_EXP_STRING;
			$$->u.expression.u.string = "";
		}
	|	STRING_LITERAL_START s_char_sequence DQUOTE
		{
			$$ = make_node(parser_ctx, NODE_EXPRESSION);
			$$->u.expression.type = AST_EXP_STRING;
			$$->u.expression.u.string = $2->s;
		}
	|	CHARACTER_CONSTANT_START c_char_sequence SQUOTE
		{
			$$ = make_node(parser_ctx, NODE_EXPRESSION);
			$$->u.expression.type = AST_EXP_STRING;
			$$->u.expression.u.string = $2->s;
		}
	|	LPAREN expression RPAREN
		{
			$$ = make_node(parser_ctx, NODE_EXPRESSION);
			$$->u.expression.type = AST_EXP_NESTED;
			$$->u.expression.u.child = $2;
		}
	;

postfix_expression
	: primary_expression
		{	$$ = $1;					}
	| postfix_expression DOT IDENTIFIER
		{
			$$ = make_node(parser_ctx, NODE_EXPRESSION);
			$$->u.expression.type = AST_EXP_IDENTIFIER;
			$$->u.expression.post_op = AST_LINK_DOT;
			$$->u.expression.u.identifier = $3->s;
			$$->u.expression.prev = $1;
		}
	| postfix_expression RARROW IDENTIFIER
		{
			$$ = make_node(parser_ctx, NODE_EXPRESSION);
			$$->u.expression.type = AST_EXP_IDENTIFIER;
			$$->u.expression.post_op = AST_LINK_RARROW;
			$$->u.expression.u.identifier = $3->s;
			$$->u.expression.prev = $1;
		}
	;

unary_expression
	: postfix_expression
		{	$$ = $1;					}
	| unary_operator unary_expression
		{
			$$ = $1;
			$$->u.unary_op.child = $2;
		}
	;

unary_operator
	: PLUS
		{
			$$ = make_node(parser_ctx, NODE_UNARY_OP);
			$$->u.unary_op.type = AST_UNARY_PLUS;
		}
	| MINUS
		{
			$$ = make_node(parser_ctx, NODE_UNARY_OP);
			$$->u.unary_op.type = AST_UNARY_MINUS;
		}
	| NOT_OP
		{
			$$ = make_node(parser_ctx, NODE_UNARY_OP);
			$$->u.unary_op.type = AST_UNARY_NOT;
		}
	| NOT_BIN
		{
			$$ = make_node(parser_ctx, NODE_UNARY_OP);
			$$->u.unary_op.type = AST_UNARY_BIN_NOT;
		}
	;

multiplicative_expression
	: unary_expression
		{	$$ = $1;					}
	| multiplicative_expression STAR unary_expression
		{
			$$ = make_op_node(parser_ctx, AST_OP_MUL, $1, $3);
		}
	| multiplicative_expression DIV_OP unary_expression
		{
			$$ = make_op_node(parser_ctx, AST_OP_DIV, $1, $3);
		}
	| multiplicative_expression MOD_OP unary_expression
		{
			$$ = make_op_node(parser_ctx, AST_OP_MOD, $1, $3);
		}
	;

additive_expression
	: multiplicative_expression
		{	$$ = $1;					}
	| additive_expression PLUS multiplicative_expression
		{
			$$ = make_op_node(parser_ctx, AST_OP_PLUS, $1, $3);
		}
	| additive_expression MINUS multiplicative_expression
		{
			$$ = make_op_node(parser_ctx, AST_OP_MINUS, $1, $3);
		}
	;

shift_expression
	: additive_expression
		{	$$ = $1;					}
	| shift_expression LEFT_OP additive_expression
		{
			$$ = make_op_node(parser_ctx, AST_OP_LSHIFT, $1, $3);
		}
	| shift_expression RIGHT_OP additive_expression
		{
			$$ = make_op_node(parser_ctx, AST_OP_RSHIFT, $1, $3);
		}
	;

relational_expression
	: shift_expression
		{	$$ = $1;					}
	| relational_expression LT_OP shift_expression
		{
			$$ = make_op_node(parser_ctx, AST_OP_LT, $1, $3);
		}
	| relational_expression GT_OP shift_expression
		{
			$$ = make_op_node(parser_ctx, AST_OP_GT, $1, $3);
		}
	| relational_expression LE_OP shift_expression
		{
			$$ = make_op_node(parser_ctx, AST_OP_LE, $1, $3);
		}
	| relational_expression GE_OP shift_expression
		{
			$$ = make_op_node(parser_ctx, AST_OP_GE, $1, $3);
		}
	;

equality_expression
	: relational_expression
		{	$$ = $1;					}
	| equality_expression EQ_OP relational_expression
		{
			$$ = make_op_node(parser_ctx, AST_OP_EQ, $1, $3);
		}
	| equality_expression NE_OP relational_expression
		{
			$$ = make_op_node(parser_ctx, AST_OP_NE, $1, $3);
		}
	;

and_expression
	: equality_expression
		{	$$ = $1;					}
	| and_expression AND_BIN equality_expression
		{
			$$ = make_op_node(parser_ctx, AST_OP_BIN_AND, $1, $3);
		}
	;

exclusive_or_expression
	: and_expression
		{	$$ = $1;					}
	| exclusive_or_expression XOR_BIN and_expression
		{
			$$ = make_op_node(parser_ctx, AST_OP_BIN_XOR, $1, $3);
		}
	;

inclusive_or_expression
	: exclusive_or_expression
		{	$$ = $1;					}
	| inclusive_or_expression OR_BIN exclusive_or_expression
		{
			$$ = make_op_node(parser_ctx, AST_OP_BIN_OR, $1, $3);
		}
	;

logical_and_expression
	: inclusive_or_expression
		{	$$ = $1;					}
	| logical_and_expression AND_OP inclusive_or_expression
		{
			$$ = make_op_node(parser_ctx, AST_OP_AND, $1, $3);
		}
	;

logical_or_expression
	: logical_and_expression
		{	$$ = $1;					}
	| logical_or_expression OR_OP logical_and_expression
		{
			$$ = make_op_node(parser_ctx, AST_OP_OR, $1, $3);
		}
	;

expression
	: logical_or_expression
		{	$$ = $1;					}
	;

translation_unit
	: expression
		{
			parser_ctx->ast->root.u.root.child = $1;
		}
	;
Commit	Line	Data
953192ba MD	1	%{
	2	/*
	3	* filter-parser.y
	4	*
	5	* LTTng filter expression parser
	6	*
	7	* Copyright 2012 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	8	*
	9	* This library is free software; you can redistribute it and/or modify it
	10	* under the terms of the GNU Lesser General Public License, version 2.1 only,
	11	* as published by the Free Software Foundation.
	12	*
	13	* This library is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	16	* Lesser General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU Lesser General Public License
	19	* along with this library; if not, write to the Free Software Foundation,
	20	* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	21	*
	22	* Grammar inspired from http://www.quut.com/c/ANSI-C-grammar-y.html
	23	*/
	24
	25	#include <stdio.h>
	26	#include <unistd.h>
	27	#include <string.h>
	28	#include <stdlib.h>
	29	#include <assert.h>
	30	#include <errno.h>
	31	#include <inttypes.h>
953192ba	32	#include "filter-ast.h"
95b9bd90	33	#include "filter-parser.h"
953192ba	34
a187da1a DG	35	#include <common/macros.h>
a187da1a DG	36
8ab7c0d9 MD	37	#define WIDTH_u64_SCANF_IS_A_BROKEN_API "20"
	38	#define WIDTH_o64_SCANF_IS_A_BROKEN_API "22"
	39	#define WIDTH_x64_SCANF_IS_A_BROKEN_API "17"
	40	#define WIDTH_lg_SCANF_IS_A_BROKEN_API "4096" /* Hugely optimistic approximation */
	41
a187da1a	42	LTTNG_HIDDEN
953192ba	43	int yydebug;
a187da1a	44	LTTNG_HIDDEN
953192ba MD	45	int filter_parser_debug = 0;
953192ba MD	46
a187da1a	47	LTTNG_HIDDEN
9039edd4	48	int yyparse(struct filter_parser_ctx *parser_ctx, yyscan_t scanner);
a187da1a	49	LTTNG_HIDDEN
9039edd4	50	int yylex(union YYSTYPE *yyval, yyscan_t scanner);
a187da1a	51	LTTNG_HIDDEN
953192ba	52	int yylex_init_extra(struct filter_parser_ctx parser_ctx, yyscan_t ptr_yy_globals);
a187da1a	53	LTTNG_HIDDEN
953192ba	54	int yylex_destroy(yyscan_t yyparser_ctx);
a187da1a	55	LTTNG_HIDDEN
953192ba MD	56	void yyrestart(FILE * in_str, yyscan_t parser_ctx);
	57
	58	struct gc_string {
	59	struct cds_list_head gc;
	60	size_t alloclen;
	61	char s[];
	62	};
	63
	64	static const char *node_type_to_str[] = {
	65	[ NODE_UNKNOWN ] = "NODE_UNKNOWN",
	66	[ NODE_ROOT ] = "NODE_ROOT",
	67	[ NODE_EXPRESSION ] = "NODE_EXPRESSION",
	68	[ NODE_OP ] = "NODE_OP",
	69	[ NODE_UNARY_OP ] = "NODE_UNARY_OP",
	70	};
	71
a187da1a	72	LTTNG_HIDDEN
953192ba MD	73	const char node_type(struct filter_node node)
	74	{
	75	if (node->type < NR_NODE_TYPES)
	76	return node_type_to_str[node->type];
	77	else
	78	return NULL;
	79	}
	80
	81	static struct gc_string gc_string_alloc(struct filter_parser_ctx parser_ctx,
	82	size_t len)
	83	{
	84	struct gc_string *gstr;
	85	size_t alloclen;
	86
	87	/* TODO: could be faster with find first bit or glib Gstring */
	88	/* sizeof long to account for malloc header (int or long ?) */
	89	for (alloclen = 8; alloclen < sizeof(long) + sizeof(*gstr) + len;
	90	alloclen *= 2);
	91
	92	gstr = malloc(alloclen);
	93	cds_list_add(&gstr->gc, &parser_ctx->allocated_strings);
	94	gstr->alloclen = alloclen;
	95	return gstr;
	96	}
	97
	98	/*
	99	* note: never use gc_string_append on a string that has external references.
	100	* gsrc will be garbage collected immediately, and gstr might be.
	101	* Should only be used to append characters to a string literal or constant.
	102	*/
a187da1a	103	LTTNG_HIDDEN
953192ba MD	104	struct gc_string gc_string_append(struct filter_parser_ctx parser_ctx,
	105	struct gc_string *gstr,
	106	struct gc_string *gsrc)
	107	{
	108	size_t newlen = strlen(gsrc->s) + strlen(gstr->s) + 1;
	109	size_t alloclen;
	110
	111	/* TODO: could be faster with find first bit or glib Gstring */
	112	/* sizeof long to account for malloc header (int or long ?) */
	113	for (alloclen = 8; alloclen < sizeof(long) + sizeof(*gstr) + newlen;
	114	alloclen *= 2);
	115
	116	if (alloclen > gstr->alloclen) {
	117	struct gc_string *newgstr;
	118
	119	newgstr = gc_string_alloc(parser_ctx, newlen);
	120	strcpy(newgstr->s, gstr->s);
	121	strcat(newgstr->s, gsrc->s);
	122	cds_list_del(&gstr->gc);
	123	free(gstr);
	124	gstr = newgstr;
	125	} else {
	126	strcat(gstr->s, gsrc->s);
	127	}
	128	cds_list_del(&gsrc->gc);
	129	free(gsrc);
	130	return gstr;
	131	}
	132
a187da1a	133	LTTNG_HIDDEN
953192ba MD	134	void setstring(struct filter_parser_ctx parser_ctx, YYSTYPE lvalp, const char *src)
	135	{
	136	lvalp->gs = gc_string_alloc(parser_ctx, strlen(src) + 1);
	137	strcpy(lvalp->gs->s, src);
	138	}
	139
	140	static struct filter_node make_node(struct filter_parser_ctx scanner,
	141	enum node_type type)
	142	{
	143	struct filter_ast *ast = filter_parser_get_ast(scanner);
	144	struct filter_node *node;
	145
	146	node = malloc(sizeof(*node));
	147	if (!node)
	148	return NULL;
	149	memset(node, 0, sizeof(*node));
	150	node->type = type;
	151	cds_list_add(&node->gc, &ast->allocated_nodes);
	152
	153	switch (type) {
	154	case NODE_ROOT:
	155	fprintf(stderr, "[error] %s: trying to create root node\n", __func__);
	156	break;
	157
	158	case NODE_EXPRESSION:
	159	break;
	160	case NODE_OP:
	161	break;
	162	case NODE_UNARY_OP:
	163	break;
	164
	165	case NODE_UNKNOWN:
	166	default:
	167	fprintf(stderr, "[error] %s: unknown node type %d\n", __func__,
	168	(int) type);
	169	break;
	170	}
	171
	172	return node;
	173	}
	174
	175	static struct filter_node make_op_node(struct filter_parser_ctx scanner,
	176	enum op_type type,
	177	struct filter_node *lchild,
	178	struct filter_node *rchild)
	179	{
	180	struct filter_ast *ast = filter_parser_get_ast(scanner);
	181	struct filter_node *node;
	182
	183	node = malloc(sizeof(*node));
	184	if (!node)
	185	return NULL;
	186	memset(node, 0, sizeof(*node));
	187	node->type = NODE_OP;
	188	cds_list_add(&node->gc, &ast->allocated_nodes);
	189	node->u.op.type = type;
	190	node->u.op.lchild = lchild;
	191	node->u.op.rchild = rchild;
	192	return node;
	193	}
	194
a187da1a	195	LTTNG_HIDDEN
9039edd4	196	void yyerror(struct filter_parser_ctx parser_ctx, yyscan_t scanner, const char str)
953192ba MD	197	{
	198	fprintf(stderr, "error %s\n", str);
	199	}
	200
a187da1a	201	LTTNG_HIDDEN
953192ba MD	202	int yywrap(void)
	203	{
	204	return 1;
	205	}
	206
	207	#define parse_error(parser_ctx, str) \
	208	do { \
9039edd4	209	yyerror(parser_ctx, parser_ctx->scanner, YY_("parse error: " str "\n")); \
953192ba MD	210	YYERROR; \
	211	} while (0)
	212
	213	static void free_strings(struct cds_list_head *list)
	214	{
	215	struct gc_string gstr, tmp;
	216
	217	cds_list_for_each_entry_safe(gstr, tmp, list, gc)
	218	free(gstr);
	219	}
	220
	221	static struct filter_ast *filter_ast_alloc(void)
	222	{
	223	struct filter_ast *ast;
	224
	225	ast = malloc(sizeof(*ast));
	226	if (!ast)
	227	return NULL;
	228	memset(ast, 0, sizeof(*ast));
	229	CDS_INIT_LIST_HEAD(&ast->allocated_nodes);
	230	ast->root.type = NODE_ROOT;
	231	return ast;
	232	}
	233
	234	static void filter_ast_free(struct filter_ast *ast)
	235	{
	236	struct filter_node node, tmp;
	237
	238	cds_list_for_each_entry_safe(node, tmp, &ast->allocated_nodes, gc)
	239	free(node);
37600d79	240	free(ast);
953192ba MD	241	}
953192ba MD	242
a187da1a	243	LTTNG_HIDDEN
953192ba MD	244	int filter_parser_ctx_append_ast(struct filter_parser_ctx *parser_ctx)
953192ba MD	245	{
9039edd4	246	return yyparse(parser_ctx, parser_ctx->scanner);
953192ba MD	247	}
953192ba MD	248
a187da1a	249	LTTNG_HIDDEN
953192ba MD	250	struct filter_parser_ctx filter_parser_ctx_alloc(FILE input)
	251	{
	252	struct filter_parser_ctx *parser_ctx;
	253	int ret;
	254
	255	yydebug = filter_parser_debug;
	256
	257	parser_ctx = malloc(sizeof(*parser_ctx));
	258	if (!parser_ctx)
	259	return NULL;
	260	memset(parser_ctx, 0, sizeof(*parser_ctx));
	261
	262	ret = yylex_init_extra(parser_ctx, &parser_ctx->scanner);
	263	if (ret) {
	264	fprintf(stderr, "yylex_init error\n");
	265	goto cleanup_parser_ctx;
	266	}
	267	/* Start processing new stream */
	268	yyrestart(input, parser_ctx->scanner);
	269
	270	parser_ctx->ast = filter_ast_alloc();
	271	if (!parser_ctx->ast)
	272	goto cleanup_lexer;
	273	CDS_INIT_LIST_HEAD(&parser_ctx->allocated_strings);
	274
	275	if (yydebug)
	276	fprintf(stdout, "parser_ctx input is a%s.\n",
	277	isatty(fileno(input)) ? "n interactive tty" :
	278	" noninteractive file");
	279
	280	return parser_ctx;
	281
	282	cleanup_lexer:
	283	ret = yylex_destroy(parser_ctx->scanner);
	284	if (!ret)
	285	fprintf(stderr, "yylex_destroy error\n");
	286	cleanup_parser_ctx:
	287	free(parser_ctx);
	288	return NULL;
	289	}
	290
a187da1a	291	LTTNG_HIDDEN
953192ba MD	292	void filter_parser_ctx_free(struct filter_parser_ctx *parser_ctx)
	293	{
	294	int ret;
	295
	296	free_strings(&parser_ctx->allocated_strings);
	297	filter_ast_free(parser_ctx->ast);
	298	ret = yylex_destroy(parser_ctx->scanner);
	299	if (ret)
	300	fprintf(stderr, "yylex_destroy error\n");
	301	free(parser_ctx);
	302	}
	303
	304	%}
	305
	306	%define api.pure
	307	/* %locations */
	308	%parse-param {struct filter_parser_ctx *parser_ctx}
9039edd4 ZT	309	%parse-param {yyscan_t scanner}
9039edd4 ZT	310	%lex-param {yyscan_t scanner}
953192ba MD	311	%start translation_unit
	312	%token CHARACTER_CONSTANT_START SQUOTE STRING_LITERAL_START DQUOTE
	313	%token ESCSEQ CHAR_STRING_TOKEN
e90d8561	314	%token DECIMAL_CONSTANT OCTAL_CONSTANT HEXADECIMAL_CONSTANT FLOAT_CONSTANT
953192ba MD	315	%token LSBRAC RSBRAC LPAREN RPAREN LBRAC RBRAC RARROW
	316	%token STAR PLUS MINUS
	317	%token MOD_OP DIV_OP RIGHT_OP LEFT_OP
	318	%token EQ_OP NE_OP LE_OP GE_OP LT_OP GT_OP AND_OP OR_OP NOT_OP
	319	%token ASSIGN COLON SEMICOLON DOTDOTDOT DOT EQUAL COMMA
	320	%token XOR_BIN AND_BIN OR_BIN NOT_BIN
	321
586dc72f	322	%token <gs> IDENTIFIER GLOBAL_IDENTIFIER
953192ba MD	323	%token ERROR
	324	%union
	325	{
	326	long long ll;
	327	char c;
	328	struct gc_string *gs;
	329	struct filter_node *n;
	330	}
	331
	332	%type <gs> s_char s_char_sequence c_char c_char_sequence
	333
	334	%type <n> primary_expression
	335	%type <n> postfix_expression
	336	%type <n> unary_expression
	337	%type <n> unary_operator
	338	%type <n> multiplicative_expression
	339	%type <n> additive_expression
	340	%type <n> shift_expression
	341	%type <n> relational_expression
	342	%type <n> equality_expression
	343	%type <n> and_expression
	344	%type <n> exclusive_or_expression
	345	%type <n> inclusive_or_expression
	346	%type <n> logical_and_expression
	347	%type <n> logical_or_expression
	348	%type <n> expression
	349
	350	%%
	351
	352
	353	/* 1.5 Constants */
	354
	355	c_char_sequence:
	356	c_char
	357	{ $$ = $1; }
	358	\| c_char_sequence c_char
	359	{ $$ = gc_string_append(parser_ctx, $1, $2); }
	360	;
	361
	362	c_char:
	363	CHAR_STRING_TOKEN
	364	{ $$ = yylval.gs; }
	365	\| ESCSEQ
	366	{
	367	parse_error(parser_ctx, "escape sequences not supported yet");
	368	}
	369	;
	370
	371	/* 1.6 String literals */
	372
	373	s_char_sequence:
	374	s_char
	375	{ $$ = $1; }
	376	\| s_char_sequence s_char
	377	{ $$ = gc_string_append(parser_ctx, $1, $2); }
	378	;
	379
	380	s_char:
	381	CHAR_STRING_TOKEN
	382	{ $$ = yylval.gs; }
	383	\| ESCSEQ
	384	{
	385	parse_error(parser_ctx, "escape sequences not supported yet");
	386	}
387	;
388
389	primary_expression
390	: IDENTIFIER
391	{
392	$$ = make_node(parser_ctx, NODE_EXPRESSION);
393	$$->u.expression.type = AST_EXP_IDENTIFIER;
394	$$->u.expression.u.identifier = yylval.gs->s;
395	}
586dc72f MD	396	\| GLOBAL_IDENTIFIER
	397	{
	398	$$ = make_node(parser_ctx, NODE_EXPRESSION);
	399	$$->u.expression.type = AST_EXP_GLOBAL_IDENTIFIER;
	400	$$->u.expression.u.identifier = yylval.gs->s;
	401	}
	402
953192ba MD	403	\| DECIMAL_CONSTANT
	404	{
	405	$$ = make_node(parser_ctx, NODE_EXPRESSION);
	406	$$->u.expression.type = AST_EXP_CONSTANT;
8ab7c0d9 MD	407	if (sscanf(yylval.gs->s, "%" WIDTH_u64_SCANF_IS_A_BROKEN_API SCNu64,
	408	&$$->u.expression.u.constant) != 1) {
	409	parse_error(parser_ctx, "cannot scanf decimal constant");
	410	}
953192ba MD	411	}
	412	\| OCTAL_CONSTANT
	413	{
	414	$$ = make_node(parser_ctx, NODE_EXPRESSION);
	415	$$->u.expression.type = AST_EXP_CONSTANT;
8ab7c0d9 MD	416	if (!strcmp(yylval.gs->s, "0")) {
	417	$$->u.expression.u.constant = 0;
	418	} else if (sscanf(yylval.gs->s, "0%" WIDTH_o64_SCANF_IS_A_BROKEN_API SCNo64,
	419	&$$->u.expression.u.constant) != 1) {
	420	parse_error(parser_ctx, "cannot scanf octal constant");
	421	}
953192ba MD	422	}
	423	\| HEXADECIMAL_CONSTANT
	424	{
	425	$$ = make_node(parser_ctx, NODE_EXPRESSION);
	426	$$->u.expression.type = AST_EXP_CONSTANT;
8ab7c0d9 MD	427	if (sscanf(yylval.gs->s, "0x%" WIDTH_x64_SCANF_IS_A_BROKEN_API SCNx64,
	428	&$$->u.expression.u.constant) != 1) {
	429	parse_error(parser_ctx, "cannot scanf hexadecimal constant");
	430	}
953192ba	431	}
e90d8561 MD	432	\| FLOAT_CONSTANT
	433	{
	434	$$ = make_node(parser_ctx, NODE_EXPRESSION);
	435	$$->u.expression.type = AST_EXP_FLOAT_CONSTANT;
8ab7c0d9 MD	436	if (sscanf(yylval.gs->s, "%" WIDTH_lg_SCANF_IS_A_BROKEN_API "lg",
	437	&$$->u.expression.u.float_constant) != 1) {
	438	parse_error(parser_ctx, "cannot scanf float constant");
	439	}
e90d8561	440	}
953192ba MD	441	\| STRING_LITERAL_START DQUOTE
	442	{
	443	$$ = make_node(parser_ctx, NODE_EXPRESSION);
	444	$$->u.expression.type = AST_EXP_STRING;
	445	$$->u.expression.u.string = "";
	446	}
	447	\| STRING_LITERAL_START s_char_sequence DQUOTE
	448	{
	449	$$ = make_node(parser_ctx, NODE_EXPRESSION);
	450	$$->u.expression.type = AST_EXP_STRING;
	451	$$->u.expression.u.string = $2->s;
	452	}
	453	\| CHARACTER_CONSTANT_START c_char_sequence SQUOTE
	454	{
	455	$$ = make_node(parser_ctx, NODE_EXPRESSION);
	456	$$->u.expression.type = AST_EXP_STRING;
	457	$$->u.expression.u.string = $2->s;
	458	}
	459	\| LPAREN expression RPAREN
	460	{
	461	$$ = make_node(parser_ctx, NODE_EXPRESSION);
	462	$$->u.expression.type = AST_EXP_NESTED;
	463	$$->u.expression.u.child = $2;
	464	}
	465	;
	466
	467	postfix_expression
	468	: primary_expression
	469	{ $$ = $1; }
	470	\| postfix_expression DOT IDENTIFIER
	471	{
	472	$$ = make_node(parser_ctx, NODE_EXPRESSION);
	473	$$->u.expression.type = AST_EXP_IDENTIFIER;
	474	$$->u.expression.post_op = AST_LINK_DOT;
	475	$$->u.expression.u.identifier = $3->s;
	476	$$->u.expression.prev = $1;
	477	}
	478	\| postfix_expression RARROW IDENTIFIER
	479	{
	480	$$ = make_node(parser_ctx, NODE_EXPRESSION);
	481	$$->u.expression.type = AST_EXP_IDENTIFIER;
	482	$$->u.expression.post_op = AST_LINK_RARROW;
	483	$$->u.expression.u.identifier = $3->s;
	484	$$->u.expression.prev = $1;
	485	}
	486	;
	487
	488	unary_expression
	489	: postfix_expression
	490	{ $$ = $1; }
	491	\| unary_operator unary_expression
	492	{
	493	$$ = $1;
	494	$$->u.unary_op.child = $2;
	495	}
	496	;
	497
	498	unary_operator
	499	: PLUS
	500	{
	501	$$ = make_node(parser_ctx, NODE_UNARY_OP);
	502	$$->u.unary_op.type = AST_UNARY_PLUS;
	503	}
	504	\| MINUS
505	{
506	$$ = make_node(parser_ctx, NODE_UNARY_OP);
507	$$->u.unary_op.type = AST_UNARY_MINUS;
508	}
509	\| NOT_OP
510	{
511	$$ = make_node(parser_ctx, NODE_UNARY_OP);
512	$$->u.unary_op.type = AST_UNARY_NOT;
513	}
ab78f161 CB	514	\| NOT_BIN
	515	{
	516	$$ = make_node(parser_ctx, NODE_UNARY_OP);
	517	$$->u.unary_op.type = AST_UNARY_BIN_NOT;
	518	}
953192ba MD	519	;
	520
	521	multiplicative_expression
	522	: unary_expression
	523	{ $$ = $1; }
	524	\| multiplicative_expression STAR unary_expression
	525	{
	526	$$ = make_op_node(parser_ctx, AST_OP_MUL, $1, $3);
	527	}
	528	\| multiplicative_expression DIV_OP unary_expression
	529	{
	530	$$ = make_op_node(parser_ctx, AST_OP_DIV, $1, $3);
	531	}
	532	\| multiplicative_expression MOD_OP unary_expression
	533	{
	534	$$ = make_op_node(parser_ctx, AST_OP_MOD, $1, $3);
	535	}
	536	;
	537
	538	additive_expression
	539	: multiplicative_expression
	540	{ $$ = $1; }
	541	\| additive_expression PLUS multiplicative_expression
	542	{
	543	$$ = make_op_node(parser_ctx, AST_OP_PLUS, $1, $3);
	544	}
	545	\| additive_expression MINUS multiplicative_expression
	546	{
	547	$$ = make_op_node(parser_ctx, AST_OP_MINUS, $1, $3);
	548	}
	549	;
	550
	551	shift_expression
	552	: additive_expression
	553	{ $$ = $1; }
	554	\| shift_expression LEFT_OP additive_expression
	555	{
	556	$$ = make_op_node(parser_ctx, AST_OP_LSHIFT, $1, $3);
	557	}
	558	\| shift_expression RIGHT_OP additive_expression
	559	{
	560	$$ = make_op_node(parser_ctx, AST_OP_RSHIFT, $1, $3);
	561	}
	562	;
	563
	564	relational_expression
	565	: shift_expression
	566	{ $$ = $1; }
	567	\| relational_expression LT_OP shift_expression
	568	{
	569	$$ = make_op_node(parser_ctx, AST_OP_LT, $1, $3);
	570	}
	571	\| relational_expression GT_OP shift_expression
	572	{
	573	$$ = make_op_node(parser_ctx, AST_OP_GT, $1, $3);
	574	}
	575	\| relational_expression LE_OP shift_expression
	576	{
	577	$$ = make_op_node(parser_ctx, AST_OP_LE, $1, $3);
	578	}
	579	\| relational_expression GE_OP shift_expression
	580	{
	581	$$ = make_op_node(parser_ctx, AST_OP_GE, $1, $3);
	582	}
583	;
584
585	equality_expression
586	: relational_expression
587	{ $$ = $1; }
588	\| equality_expression EQ_OP relational_expression
589	{
590	$$ = make_op_node(parser_ctx, AST_OP_EQ, $1, $3);
591	}
592	\| equality_expression NE_OP relational_expression
593	{
594	$$ = make_op_node(parser_ctx, AST_OP_NE, $1, $3);
595	}
596	;
597
598	and_expression
599	: equality_expression
600	{ $$ = $1; }
601	\| and_expression AND_BIN equality_expression
602	{
603	$$ = make_op_node(parser_ctx, AST_OP_BIN_AND, $1, $3);
604	}
605	;
606
607	exclusive_or_expression
608	: and_expression
609	{ $$ = $1; }
610	\| exclusive_or_expression XOR_BIN and_expression
611	{
612	$$ = make_op_node(parser_ctx, AST_OP_BIN_XOR, $1, $3);
613	}
614	;
615
616	inclusive_or_expression
617	: exclusive_or_expression
618	{ $$ = $1; }
619	\| inclusive_or_expression OR_BIN exclusive_or_expression
620	{
621	$$ = make_op_node(parser_ctx, AST_OP_BIN_OR, $1, $3);
622	}
623	;
624
625	logical_and_expression
626	: inclusive_or_expression
627	{ $$ = $1; }
628	\| logical_and_expression AND_OP inclusive_or_expression
629	{
630	$$ = make_op_node(parser_ctx, AST_OP_AND, $1, $3);
631	}
632	;
633
634	logical_or_expression
635	: logical_and_expression
636	{ $$ = $1; }
637	\| logical_or_expression OR_OP logical_and_expression
638	{
639	$$ = make_op_node(parser_ctx, AST_OP_OR, $1, $3);
640	}
641	;
642
643	expression
644	: logical_or_expression
645	{ $$ = $1; }
646	;
647
648	translation_unit
649	: expression
650	{
651	parser_ctx->ast->root.u.root.child = $1;
652	}
653	;