php_syntree.cpp

电驴的MAC源代码

//
// This file is part of the aMule Project.
//
// Copyright (c) 2003-2008 aMule Team ( [e-mail] / http://www.amule.org )
// Copyright (C) 2005-2008 Froenchenko Leonid ( [e-mail] )
//
// Any parts of this program derived from the xMule, lMule or eMule project,
// or contributed by third-party developers are copyrighted by their
// respective authors.
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// 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 St, Fifth Floor, Boston, MA  02110-1301, USA
//


#include <string> // Do_not_auto_remove (g++-4.0.1)

#ifdef PHP_STANDALONE_EN
	#include <map>
	#include <list>
	#include <stdarg.h>
#else
	#include "WebServer.h"
#endif


#include "php_syntree.h"
#include "php_core_lib.h"


PHP_SYN_NODE *g_syn_tree_top = 0;

/* scope table */
PHP_SCOPE_TABLE g_global_scope = 0;
PHP_SCOPE_TABLE g_current_scope = 0;
PHP_SCOPE_STACK g_scope_stack = 0;


//
// Known named constant values
std::map<std::string, int> g_known_const;

PHP_EXP_NODE *make_zero_exp_node()
{
	PHP_EXP_NODE *node = new PHP_EXP_NODE;
	memset(node, 0, sizeof(PHP_EXP_NODE));
	return node;
}

PHP_EXP_NODE *make_const_exp_dnum(int number)
{
	PHP_EXP_NODE *node = make_zero_exp_node();
	node->op = PHP_OP_VAL;
	node->val_node.type = PHP_VAL_INT;
	node->val_node.int_val = number;
	
	return node;
}

PHP_EXP_NODE *make_const_exp_fnum(float number)
{
	PHP_EXP_NODE *node = make_zero_exp_node();
	node->op = PHP_OP_VAL;
	node->val_node.type = PHP_VAL_FLOAT;
	node->val_node.float_val = number;
	
	return node;
}

PHP_EXP_NODE *make_const_exp_str(char *s, int unescape)
{
	PHP_EXP_NODE *node = make_zero_exp_node();
	node->op = PHP_OP_VAL;
	node->val_node.type = PHP_VAL_STRING;

	if ( unescape ) {
		node->val_node.str_val = (char *)malloc(strlen(s)+1);
		// copy and unescape string
		char *p = node->val_node.str_val;
		while(*s) {
			if ( *s == '\\' ) {
				switch ( *(++s) ) {
					case 'n' : *p++ = '\n'; s++; break;
					case 't' : *p++ = '\t'; s++; break;
					default  : *p++ = *s++; break;
				}
			} else {
				*p++ = *s++;
			}
		}
		*p = 0;
	} else {
		node->val_node.str_val = strdup(s);
	}
	
	return node;
}

PHP_EXP_NODE *make_const_exp_int_obj(void *obj)
{
	PHP_EXP_NODE *node = make_zero_exp_node();
	node->op = PHP_OP_VAL;
	node->val_node.type = PHP_VAL_INT_DATA;
	node->val_node.ptr_val = obj;
	
	return node;
}

PHP_EXP_NODE *make_exp_1(PHP_EXP_OP op, PHP_EXP_NODE *operand)
{
	PHP_EXP_NODE *node = make_zero_exp_node();
	node->op = op;
	node->tree_node.left = operand;
	return node;
}

PHP_EXP_NODE *make_exp_2(PHP_EXP_OP op, PHP_EXP_NODE *left, PHP_EXP_NODE *right)
{
	PHP_EXP_NODE *node = make_zero_exp_node();
	node->op = op;
	node->tree_node.left = left;
	node->tree_node.right = right;
	return node;
}

PHP_EXP_NODE *make_exp_2_self(PHP_EXP_OP op, PHP_EXP_NODE *self, PHP_EXP_NODE *right)
{
	PHP_EXP_NODE *clone_self = make_zero_exp_node();
	*clone_self = *self;
	return make_exp_2(op, clone_self, right);
}

PHP_EXP_NODE *make_known_const(char *name)
{
	int const_id = -1;
	if ( g_known_const.count(name) ) {
		const_id = g_known_const[name];
	}
	return make_const_exp_dnum(const_id);
}

//
// Create function parameter (in declaration)
//
PHP_EXP_NODE *make_func_param(PHP_EXP_NODE *list, PHP_EXP_NODE *var_exp_node, char *class_name, int byref)
{
	PHP_FUNC_PARAM_DEF *param = new PHP_FUNC_PARAM_DEF;
	memset(param, 0, sizeof(PHP_FUNC_PARAM_DEF));

	param->si_var = var_exp_node->var_si_node;
	param->si_var->type = PHP_SCOPE_PARAM;
	//printf("mark %p->%p as param\n", param->si_var, param->si_var->var);
	
	param->var = param->si_var->var;
	
	delete var_exp_node;
	param->class_name = class_name ? strdup(class_name) : 0;
	param->byref = byref;
	
	PHP_EXP_NODE *curr_node = make_const_exp_int_obj(param);
	
	if ( list ) {
		PHP_EXP_NODE *p = list;
		while ( p->next) {
			p = p->next;
		}
		p->next = curr_node;
		return list;
	} else {
		return curr_node;
	}
}

/*
 * Syntax tree generation
 */
PHP_SYN_NODE *make_expr_syn_node(PHP_STATMENT_TYPE type, PHP_EXP_NODE *expr)
{
	PHP_SYN_NODE *syn_node = new PHP_SYN_NODE;
	memset(syn_node, 0, sizeof(PHP_SYN_NODE));
	
	syn_node->type = type;
	syn_node->node_expr = expr;
	
	return syn_node;
}

PHP_SYN_NODE *make_ifelse_syn_node(PHP_EXP_NODE *expr,
	PHP_SYN_NODE *then_node, PHP_SYN_NODE *elseif_list, PHP_SYN_NODE *else_node)
{
	PHP_SYN_NODE *syn_node = new PHP_SYN_NODE;
	memset(syn_node, 0, sizeof(PHP_SYN_NODE));
	
	syn_node->type = PHP_ST_IF;
	syn_node->node_if.cond = expr;
	syn_node->node_if.code_if = then_node;
	
	if ( elseif_list ) {
		syn_node->node_if.code_else = elseif_list;
	
		PHP_SYN_NODE *curr_if = elseif_list;
		while ( curr_if->node_if.code_else ) {
			curr_if = curr_if->node_if.code_else;
		}
		curr_if->node_if.code_else = else_node;
	} else {
		syn_node->node_if.code_else = else_node;
	}
	return syn_node;
}

PHP_SYN_NODE *make_while_loop_syn_node(PHP_EXP_NODE *cond, PHP_SYN_NODE *code, int do_while)
{
	PHP_SYN_NODE *syn_node = new PHP_SYN_NODE;
	memset(syn_node, 0, sizeof(PHP_SYN_NODE));
	
	syn_node->type = do_while ? PHP_ST_WHILE : PHP_ST_DO_WHILE;
	syn_node->node_while.cond = cond;
	syn_node->node_while.code = code;
	
	return syn_node;
}

PHP_SYN_NODE *make_for_syn_node(PHP_EXP_NODE *start, PHP_EXP_NODE *cond,
	PHP_EXP_NODE *next, PHP_SYN_NODE *code)
{
	PHP_SYN_NODE *syn_node = new PHP_SYN_NODE;
	memset(syn_node, 0, sizeof(PHP_SYN_NODE));

	syn_node->type = PHP_ST_FOR;
	syn_node->node_for.do_start = start;
	syn_node->node_for.cond = cond;
	syn_node->node_for.do_next = next;
	syn_node->node_for.code = code;
	
	return syn_node;
}

PHP_SYN_NODE *make_foreach_loop_syn_node(PHP_EXP_NODE *elems,
	PHP_EXP_NODE *i_key, PHP_EXP_NODE *i_val, PHP_SYN_NODE *code, int byref)
{
	PHP_SYN_NODE *syn_node = new PHP_SYN_NODE;
	memset(syn_node, 0, sizeof(PHP_SYN_NODE));
	
	syn_node->type = PHP_ST_FOREACH;
	syn_node->node_foreach.elems = elems;
	syn_node->node_foreach.code = code;
	syn_node->node_foreach.i_key = i_key ? i_key->var_si_node : 0;
	syn_node->node_foreach.i_val = i_val->var_si_node;
	syn_node->node_foreach.byref = byref;
	
	if ( i_key ) {
		delete i_key;
	}
	delete i_val;
	
	return syn_node;
}

PHP_SYN_NODE *make_func_decl_syn_node(const char *name, PHP_EXP_NODE *param_list)
{
	PHP_SYN_NODE *syn_node = new PHP_SYN_NODE;
	memset(syn_node, 0, sizeof(PHP_SYN_NODE));
	
	syn_node->type = PHP_ST_FUNC_DECL;
	
	syn_node->func_decl = new PHP_SYN_FUNC_DECL_NODE;
	memset(syn_node->func_decl, 0, sizeof(PHP_SYN_FUNC_DECL_NODE));
	syn_node->func_decl->name = strdup(name);
	
	if ( param_list ) {
		PHP_EXP_NODE *curr_param = param_list;
		// count parameters first
		while ( curr_param ) {
			syn_node->func_decl->param_count++;
			curr_param = curr_param->next;
		}
		syn_node->func_decl->params = new PHP_FUNC_PARAM_DEF[syn_node->func_decl->param_count];
		curr_param = param_list;
		for(int i = 0; param_list; param_list = param_list->next, i++) {
			syn_node->func_decl->params[i] = *(PHP_FUNC_PARAM_DEF *)param_list->val_node.ptr_val;
			// param has been copied to array, so it's no longer needed
			delete (PHP_FUNC_PARAM_DEF *)param_list->val_node.ptr_val;
		}
		// dispose linked list as well
		while ( curr_param ) {
			PHP_EXP_NODE *p = curr_param->next;
			delete curr_param;
			curr_param = p;
		}
	}
	
	return syn_node;
}

PHP_SYN_NODE *make_class_decl_syn_node()
{
	PHP_SYN_NODE *syn_node = new PHP_SYN_NODE;
	memset(syn_node, 0, sizeof(PHP_SYN_NODE));
	
	syn_node->type = PHP_ST_CLASS_DECL;
	
	syn_node->class_decl = new PHP_SYN_CLASS_DECL_NODE;
	memset(syn_node->class_decl, 0, sizeof(PHP_SYN_CLASS_DECL_NODE));
	
	return syn_node;
}

PHP_SYN_NODE *make_switch_syn_node(PHP_EXP_NODE *cond, PHP_EXP_NODE *case_list)
{
	PHP_SYN_NODE *syn_node = new PHP_SYN_NODE;
	memset(syn_node, 0, sizeof(PHP_SYN_NODE));
	
	syn_node->type = PHP_ST_SWITCH;
	
	//
	// Bind all statement lists into single one for
	// simplier execution
	//
	PHP_SYN_NODE *stat_list_tail = 0;
	for(PHP_EXP_NODE *cur_case = case_list; cur_case; cur_case = cur_case->next) {
		PHP_SYN_NODE *cur_stat_list = cur_case->exp_node->tree_node.syn_right;
		if ( stat_list_tail ) {
			while ( stat_list_tail->next_node ) stat_list_tail = stat_list_tail->next_node;
			stat_list_tail->next_node = cur_stat_list;
		} else {
			stat_list_tail = cur_stat_list;
		}
	}
		
	syn_node->node_switch.cond = cond;
	syn_node->node_switch.case_list = case_list;
	
	return syn_node;
}

PHP_VAR_NODE *make_var_node()
{
	PHP_VAR_NODE *node = new PHP_VAR_NODE;
	memset(node, 0, sizeof(PHP_VAR_NODE));
	node->value.type = PHP_VAL_NONE;
	
	return node;
}

PHP_VAR_NODE *make_array_var()
{
	PHP_VAR_NODE *node = make_var_node();
	cast_value_array(&node->value);
	
	return node;
}

/*
 * Called from lexer when ${IDENT} is recognized
 */
PHP_EXP_NODE *get_var_node(const char *name)
{
	PHP_EXP_NODE *node = make_zero_exp_node();
	node->op = PHP_OP_VAR;
	
	PHP_SCOPE_ITEM *si = get_scope_item(g_current_scope, name);
	if ( si ) {
		if ( (si->type == PHP_SCOPE_VAR) || (si->type == PHP_SCOPE_PARAM) ) {
			node->var_si_node = si;
		} else {
			//
			// Error: symbol already defined as different entity
			//
			php_report_error(PHP_ERROR,
				"symbol [%s] already defined as different entity (%d)", name, si->type);
		}
	} else {
		add_var_2_scope(g_current_scope, make_var_node(), name);
		node->var_si_node = get_scope_item(g_current_scope, name);
	}
	
	return node;
}

void free_var_node(PHP_VAR_NODE *v)
{
	delete v;
}

/*
 * Init function scope table before transferring control there.
 *  1. Evaluate all by-value params
 *  2. Lvalue-evaluate all by-ref params and adjust pointers
 */
void func_scope_init(PHP_FUNC_PARAM_DEF *params, int param_count,
	PHP_SCOPE_TABLE_TYPE * /*scope_map*/, PHP_VALUE_NODE *arg_array,
	std::map<std::string, PHP_VAR_NODE *> &saved_vars)
{
	//
	// Step 1: save origival vars
	PHP_SCOPE_TABLE_TYPE *curr_scope_map = (PHP_SCOPE_TABLE_TYPE *)g_current_scope;
	for(PHP_SCOPE_TABLE_TYPE::iterator i = curr_scope_map->begin(); i != curr_scope_map->end();i++) {
		if ( (i->second->type == PHP_SCOPE_VAR) || (i->second->type == PHP_SCOPE_PARAM) ) {
			if ( !(i->second->var->flags & PHP_VARFLAG_STATIC) ) {
				//printf("Saving %s = %p->%p\n", i->first.c_str(), i->second, i->second->var);
				saved_vars[i->first] = i->second->var;
			}
		}
	}
	//
	// Step 2: calculate new values of call parameters
	PHP_VAR_NODE *call_params[PHP_MAX_FUNC_PARAM];
	for(int i = 0; i < param_count; i++) {
		PHP_VAR_NODE *curr_arg_val = array_get_by_int_key(arg_array, i);
		if ( curr_arg_val->value.type != PHP_VAL_NONE ) {
			if ( (curr_arg_val->flags & PHP_VARFLAG_BYREF) || params[i].byref ) {
				call_params[i] = php_expr_eval_lvalue((PHP_EXP_NODE *)curr_arg_val->value.ptr_val);
				if ( !call_params[i] ) {
					php_report_error(PHP_ERROR, "Byref parameter is not lvalue");
					return;
				}
			} else {
				call_params[i] = make_var_node();
				call_params[i]->ref_count = 1;
				//printf("alloc var for callparam %d -> %p\n", i, call_params[i]);
				php_expr_eval((PHP_EXP_NODE *)curr_arg_val->value.ptr_val, &call_params[i]->value);
			}
		} else {
			// put default value
			php_report_error(PHP_WARNING, "Default parameters are not implemented yet");
			call_params[i] = make_var_node();
			call_params[i]->ref_count = 1;
		}
	}
	//
	// Step 3: assign new values to call parameters
	for(int i = 0; i < param_count; i++) {
		//printf("assign new param si=%p var=%p -> %p\n", params[i].si_var, params[i].si_var->var, call_params[i]);
		params[i].si_var->var = call_params[i];
	}

	//
	// Step 4: allocate new stack local vars
	for(PHP_SCOPE_TABLE_TYPE::iterator i = curr_scope_map->begin(); i != curr_scope_map->end();i++) {
		if ( !((i->second->type == PHP_SCOPE_PARAM) || (i->second->type == PHP_SCOPE_VAR)) ) {
			continue;
		}
		//printf("in scope: %p %s [ %s ] with flags %02x\n", i->second, i->second->type == PHP_SCOPE_PARAM ? "param" : "var",
		//	i->first.c_str(), i->second->var->flags);
		if ( !(i->second->var->flags & PHP_VARFLAG_STATIC) && (i->second->type != PHP_SCOPE_PARAM) ) {
			//printf("alloc new for %s [ %p->%p ]\n", i->first.c_str(), i->second, i->second->var);
			i->second->var = make_var_node();
			i->second->var->ref_count = 1;
		}
	}
}

/*
 * Since by-ref params changes pointers in scope table, we need to restore them
 * to original objects, so:
 *  1. Memory will not leak
 *  2. Next call may be using same params by-value, so it need independent varnode
 */
void func_scope_copy_back(PHP_FUNC_PARAM_DEF *params, int param_count,
	PHP_SCOPE_TABLE_TYPE * /*scope_map*/, PHP_VALUE_NODE *arg_array,
	std::map<std::string, PHP_VAR_NODE *> &saved_vars)
{
	/*
	if ( param_count < array_get_size(arg_array) ) {
		param_count = array_get_size(arg_array);
	}
	*/
	PHP_VAR_NODE *call_params[PHP_MAX_FUNC_PARAM];
	int call_param_2free_count = 0;
	for(int i = 0; i < param_count; i++) {
		PHP_VAR_NODE *curr_arg_val = array_get_by_int_key(arg_array, i);
		if ( !((curr_arg_val->flags & PHP_VARFLAG_BYREF) || params[i].byref) ) {
			//printf("Delete param %d %p->%p\n", i, params[i].si_var, params[i].si_var->var);
			call_params[call_param_2free_count++] = params[i].si_var->var;
		}
		params[i].si_var->var = params[i].var;
	}
	
	PHP_SCOPE_TABLE_TYPE *curr_scope_map = (PHP_SCOPE_TABLE_TYPE *)g_current_scope;
	for(PHP_SCOPE_TABLE_TYPE::iterator i = curr_scope_map->begin(); i != curr_scope_map->end();i++) {
		if ( (i->second->type == PHP_SCOPE_VAR) || (i->second->type == PHP_SCOPE_PARAM) ) {
			if ( !(i->second->var->flags & PHP_VARFLAG_STATIC) ) {
				//printf("Restoring %s = %p->%p\n", i->first.c_str(), i->second, i->second->var);
				//assert(saved_vars[i->first]);
				if (i->second->type == PHP_SCOPE_VAR) {
					value_value_free(&i->second->var->value);
					delete i->second->var;
				}
				i->second->var = saved_vars[i->first];
			}
		}
	}
	for(int i = 0; i < call_param_2free_count; i++) {