--- /dev/null
+%{
+/*
+ * 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"
+
+__attribute__((visibility("hidden")))
+int yydebug;
+__attribute__((visibility("hidden")))
+int filter_parser_debug = 0;
+
+__attribute__((visibility("hidden")))
+int yyparse(struct filter_parser_ctx *parser_ctx);
+__attribute__((visibility("hidden")))
+int yylex(union YYSTYPE *yyval, struct filter_parser_ctx *parser_ctx);
+__attribute__((visibility("hidden")))
+int yylex_init_extra(struct filter_parser_ctx *parser_ctx, yyscan_t * ptr_yy_globals);
+__attribute__((visibility("hidden")))
+int yylex_destroy(yyscan_t yyparser_ctx);
+__attribute__((visibility("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",
+};
+
+__attribute__((visibility("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.
+ */
+__attribute__((visibility("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;
+}
+
+__attribute__((visibility("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;
+}
+
+__attribute__((visibility("hidden")))
+void yyerror(struct filter_parser_ctx *parser_ctx, const char *str)
+{
+ fprintf(stderr, "error %s\n", str);
+}
+
+__attribute__((visibility("hidden")))
+int yywrap(void)
+{
+ return 1;
+}
+
+#define parse_error(parser_ctx, str) \
+do { \
+ yyerror(parser_ctx, 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);
+}
+
+__attribute__((visibility("hidden")))
+int filter_parser_ctx_append_ast(struct filter_parser_ctx *parser_ctx)
+{
+ return yyparse(parser_ctx);
+}
+
+__attribute__((visibility("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;
+}
+
+__attribute__((visibility("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}
+%lex-param {struct filter_parser_ctx *parser_ctx}
+%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
+%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;
+ $$->u.expression.u.identifier = yylval.gs->s;
+ }
+ | DECIMAL_CONSTANT
+ {
+ $$ = make_node(parser_ctx, NODE_EXPRESSION);
+ $$->u.expression.type = AST_EXP_CONSTANT;
+ sscanf(yylval.gs->s, "%" PRIu64,
+ &$$->u.expression.u.constant);
+ }
+ | OCTAL_CONSTANT
+ {
+ $$ = make_node(parser_ctx, NODE_EXPRESSION);
+ $$->u.expression.type = AST_EXP_CONSTANT;
+ sscanf(yylval.gs->s, "0%" PRIo64,
+ &$$->u.expression.u.constant);
+ }
+ | HEXADECIMAL_CONSTANT
+ {
+ $$ = make_node(parser_ctx, NODE_EXPRESSION);
+ $$->u.expression.type = AST_EXP_CONSTANT;
+ sscanf(yylval.gs->s, "0x%" PRIx64,
+ &$$->u.expression.u.constant);
+ }
+ | FLOAT_CONSTANT
+ {
+ $$ = make_node(parser_ctx, NODE_EXPRESSION);
+ $$->u.expression.type = AST_EXP_FLOAT_CONSTANT;
+ sscanf(yylval.gs->s, "%lg",
+ &$$->u.expression.u.float_constant);
+ }
+ | STRING_LITERAL_START DQUOTE
+ {
+ $$ = 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;
+ }
+ ;