tokenizer.c

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/*
   +----------------------------------------------------------------------+
   | Copyright (c) The PHP Group                                          |
   +----------------------------------------------------------------------+
   | This source file is subject to version 3.01 of the PHP license,      |
   | that is bundled with this package in the file LICENSE, and is        |
   | available through the world-wide-web at the following url:           |
   | https://www.php.net/license/3_01.txt                                 |
   | If you did not receive a copy of the PHP license and are unable to   |
   | obtain it through the world-wide-web, please send a note to          |
   | license@php.net so we can mail you a copy immediately.               |
   +----------------------------------------------------------------------+
   | Author: Andrei Zmievski <andrei@php.net>                             |
   +----------------------------------------------------------------------+
*/
 
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
 
#include "php.h"
#include "ext/standard/info.h"
#include "php_tokenizer.h"
 
#include "zend.h"
#include "zend_exceptions.h"
#include "zend_language_scanner.h"
#include "zend_language_scanner_defs.h"
#include <zend_language_parser.h>
#include "zend_interfaces.h"
 
#include "tokenizer_data_arginfo.h"
#include "tokenizer_arginfo.h"
 
#define zendtext   LANG_SCNG(yy_text)
#define zendleng   LANG_SCNG(yy_leng)
#define zendcursor LANG_SCNG(yy_cursor)
#define zendlimit  LANG_SCNG(yy_limit)
 
static zend_class_entry *php_token_ce;
 
/* {{{ tokenizer_module_entry */
zend_module_entry tokenizer_module_entry = {
    STANDARD_MODULE_HEADER,
    "tokenizer",
    ext_functions,
    PHP_MINIT(tokenizer),
    NULL,
    NULL,
    NULL,
    PHP_MINFO(tokenizer),
    PHP_TOKENIZER_VERSION,
    STANDARD_MODULE_PROPERTIES
};
/* }}} */
 
#ifdef COMPILE_DL_TOKENIZER
ZEND_GET_MODULE(tokenizer)
#endif
 
static zval *php_token_get_id(zval *obj) {
    zval *id = OBJ_PROP_NUM(Z_OBJ_P(obj), 0);
    if (Z_ISUNDEF_P(id)) {
        zend_throw_error(NULL,
            "Typed property PhpToken::$id must not be accessed before initialization");
        return NULL;
    }
 
    ZVAL_DEREF(id);
    ZEND_ASSERT(Z_TYPE_P(id) == IS_LONG);
    return id;
}
 
static zend_string *php_token_get_text(zval *obj) {
    zval *text_zval = OBJ_PROP_NUM(Z_OBJ_P(obj), 1);
    if (Z_ISUNDEF_P(text_zval)) {
        zend_throw_error(NULL,
            "Typed property PhpToken::$text must not be accessed before initialization");
        return NULL;
    }
 
    ZVAL_DEREF(text_zval);
    ZEND_ASSERT(Z_TYPE_P(text_zval) == IS_STRING);
    return Z_STR_P(text_zval);
}
 
static bool tokenize_common(
        zval *return_value, zend_string *source, zend_long flags, zend_class_entry *token_class);
 
PHP_METHOD(PhpToken, tokenize)
{
    zend_string *source;
    zend_long flags = 0;
    zend_class_entry *token_class;
 
    ZEND_PARSE_PARAMETERS_START(1, 2)
        Z_PARAM_STR(source)
        Z_PARAM_OPTIONAL
        Z_PARAM_LONG(flags)
    ZEND_PARSE_PARAMETERS_END();
 
    token_class = zend_get_called_scope(execute_data);
 
    /* Check construction preconditions in advance, so these are not repeated for each token. */
    if (token_class->ce_flags & ZEND_ACC_EXPLICIT_ABSTRACT_CLASS) {
        zend_throw_error(NULL, "Cannot instantiate abstract class %s", ZSTR_VAL(token_class->name));
        RETURN_THROWS();
    }
    if (zend_update_class_constants(token_class) == FAILURE) {
        RETURN_THROWS();
    }
 
    if (!tokenize_common(return_value, source, flags, token_class)) {
        RETURN_THROWS();
    }
}
 
PHP_METHOD(PhpToken, __construct)
{
    zend_long id;
    zend_string *text;
    zend_long line = -1;
    zend_long pos = -1;
    zend_object *obj = Z_OBJ_P(ZEND_THIS);
 
    ZEND_PARSE_PARAMETERS_START(2, 4)
        Z_PARAM_LONG(id)
        Z_PARAM_STR(text)
        Z_PARAM_OPTIONAL
        Z_PARAM_LONG(line)
        Z_PARAM_LONG(pos)
    ZEND_PARSE_PARAMETERS_END();
 
    ZVAL_LONG(OBJ_PROP_NUM(obj, 0), id);
    zval_ptr_dtor(OBJ_PROP_NUM(obj, 1));
    ZVAL_STR_COPY(OBJ_PROP_NUM(obj, 1), text);
    ZVAL_LONG(OBJ_PROP_NUM(obj, 2), line);
    ZVAL_LONG(OBJ_PROP_NUM(obj, 3), pos);
}
 
PHP_METHOD(PhpToken, is)
{
    zval *kind;
 
    ZEND_PARSE_PARAMETERS_START(1, 1)
        Z_PARAM_ZVAL(kind)
    ZEND_PARSE_PARAMETERS_END();
 
    if (Z_TYPE_P(kind) == IS_LONG) {
        zval *id_zval = php_token_get_id(ZEND_THIS);
        if (!id_zval) {
            RETURN_THROWS();
        }
 
        RETURN_BOOL(Z_LVAL_P(id_zval) == Z_LVAL_P(kind));
    } else if (Z_TYPE_P(kind) == IS_STRING) {
        zend_string *text = php_token_get_text(ZEND_THIS);
        if (!text) {
            RETURN_THROWS();
        }
 
        RETURN_BOOL(zend_string_equals(text, Z_STR_P(kind)));
    } else if (Z_TYPE_P(kind) == IS_ARRAY) {
        zval *id_zval = NULL, *entry;
        zend_string *text = NULL;
        ZEND_HASH_FOREACH_VAL(Z_ARRVAL_P(kind), entry) {
            ZVAL_DEREF(entry);
            if (Z_TYPE_P(entry) == IS_LONG) {
                if (!id_zval) {
                    id_zval = php_token_get_id(ZEND_THIS);
                    if (!id_zval) {
                        RETURN_THROWS();
                    }
                }
                if (Z_LVAL_P(id_zval) == Z_LVAL_P(entry)) {
                    RETURN_TRUE;
                }
            } else if (Z_TYPE_P(entry) == IS_STRING) {
                if (!text) {
                    text = php_token_get_text(ZEND_THIS);
                    if (!text) {
                        RETURN_THROWS();
                    }
                }
                if (zend_string_equals(text, Z_STR_P(entry))) {
                    RETURN_TRUE;
                }
            } else {
                zend_argument_type_error(1, "must only have elements of type string|int, %s given", zend_zval_value_name(entry));
                RETURN_THROWS();
            }
        } ZEND_HASH_FOREACH_END();
        RETURN_FALSE;
    } else {
        zend_argument_type_error(1, "must be of type string|int|array, %s given", zend_zval_value_name(kind));
        RETURN_THROWS();
    }
}
 
PHP_METHOD(PhpToken, isIgnorable)
{
    ZEND_PARSE_PARAMETERS_NONE();
 
    zval *id_zval = php_token_get_id(ZEND_THIS);
    if (!id_zval) {
        RETURN_THROWS();
    }
 
    zend_long id = Z_LVAL_P(id_zval);
    RETURN_BOOL(id == T_WHITESPACE || id == T_COMMENT || id == T_DOC_COMMENT || id == T_OPEN_TAG);
}
 
PHP_METHOD(PhpToken, getTokenName)
{
    ZEND_PARSE_PARAMETERS_NONE();
 
    zval *id_zval = php_token_get_id(ZEND_THIS);
    if (!id_zval) {
        RETURN_THROWS();
    }
 
    if (Z_LVAL_P(id_zval) < 256) {
        RETURN_CHAR(Z_LVAL_P(id_zval));
    } else {
        const char *token_name = get_token_type_name(Z_LVAL_P(id_zval));
        if (!token_name) {
            RETURN_NULL();
        }
 
        RETURN_STRING(token_name);
    }
}
 
PHP_METHOD(PhpToken, __toString)
{
    ZEND_PARSE_PARAMETERS_NONE();
 
    zend_string *text = php_token_get_text(ZEND_THIS);
    if (!text) {
        RETURN_THROWS();
    }
 
    RETURN_STR_COPY(text);
}
 
/* {{{ PHP_MINIT_FUNCTION */
PHP_MINIT_FUNCTION(tokenizer)
{
    register_tokenizer_data_symbols(module_number);
    register_tokenizer_symbols(module_number);
    php_token_ce = register_class_PhpToken(zend_ce_stringable);
 
    return SUCCESS;
}
/* }}} */
 
/* {{{ PHP_MINFO_FUNCTION */
PHP_MINFO_FUNCTION(tokenizer)
{
    php_info_print_table_start();
    php_info_print_table_row(2, "Tokenizer Support", "enabled");
    php_info_print_table_end();
}
/* }}} */
 
static zend_string *make_str(unsigned char *text, size_t leng, HashTable *interned_strings) {
    if (leng == 1) {
        return ZSTR_CHAR(text[0]);
    } else if (interned_strings) {
        zend_string *interned_str = zend_hash_str_find_ptr(interned_strings, (char *) text, leng);
        if (interned_str) {
            return zend_string_copy(interned_str);
        }
        interned_str = zend_string_init((char *) text, leng, 0);
        zend_hash_add_new_ptr(interned_strings, interned_str, interned_str);
        return interned_str;
    } else {
        return zend_string_init((char *) text, leng, 0);
    }
}
 
static void add_token(
        zval *return_value, int token_type, unsigned char *text, size_t leng, int lineno,
        zend_class_entry *token_class, HashTable *interned_strings) {
    zval token;
    if (token_class) {
        zend_object *obj = zend_objects_new(token_class);
        ZVAL_OBJ(&token, obj);
        ZVAL_LONG(OBJ_PROP_NUM(obj, 0), token_type);
        ZVAL_STR(OBJ_PROP_NUM(obj, 1), make_str(text, leng, interned_strings));
        ZVAL_LONG(OBJ_PROP_NUM(obj, 2), lineno);
        ZVAL_LONG(OBJ_PROP_NUM(obj, 3), text - LANG_SCNG(yy_start));
 
        /* If the class is extended with additional properties, initialized them as well. */
        if (UNEXPECTED(token_class->default_properties_count > 4)) {
            zval *dst = OBJ_PROP_NUM(obj, 4);
            zval *src = &token_class->default_properties_table[4];
            zval *end = token_class->default_properties_table
                + token_class->default_properties_count;
            for (; src < end; src++, dst++) {
                ZVAL_COPY_PROP(dst, src);
            }
        }
    } else if (token_type >= 256) {
        array_init_size(&token, 3);
        zend_hash_real_init_packed(Z_ARRVAL(token));
        ZEND_HASH_FILL_PACKED(Z_ARRVAL(token)) {
            ZEND_HASH_FILL_SET_LONG(token_type);
            ZEND_HASH_FILL_NEXT();
            ZEND_HASH_FILL_SET_STR(make_str(text, leng, interned_strings));
            ZEND_HASH_FILL_NEXT();
            ZEND_HASH_FILL_SET_LONG(lineno);
            ZEND_HASH_FILL_NEXT();
        } ZEND_HASH_FILL_END();
    } else {
        ZVAL_STR(&token, make_str(text, leng, interned_strings));
    }
    zend_hash_next_index_insert_new(Z_ARRVAL_P(return_value), &token);
}
 
static bool tokenize(zval *return_value, zend_string *source, zend_class_entry *token_class)
{
    zval source_zval;
    zend_lex_state original_lex_state;
    zval token;
    int token_type;
    int token_line = 1;
    int need_tokens = -1; /* for __halt_compiler lexing. -1 = disabled */
    HashTable interned_strings;
 
    ZVAL_STR_COPY(&source_zval, source);
    zend_save_lexical_state(&original_lex_state);
 
    zend_prepare_string_for_scanning(&source_zval, ZSTR_EMPTY_ALLOC());
 
    LANG_SCNG(yy_state) = yycINITIAL;
    zend_hash_init(&interned_strings, 0, NULL, NULL, 0);
    array_init(return_value);
 
    while ((token_type = lex_scan(&token, NULL))) {
        ZEND_ASSERT(token_type != T_ERROR);
 
        add_token(
            return_value, token_type, zendtext, zendleng, token_line,
            token_class, &interned_strings);
 
        if (Z_TYPE(token) != IS_UNDEF) {
            zval_ptr_dtor_nogc(&token);
            ZVAL_UNDEF(&token);
        }
 
        /* after T_HALT_COMPILER collect the next three non-dropped tokens */
        if (need_tokens != -1) {
            if (token_type != T_WHITESPACE && token_type != T_OPEN_TAG
                && token_type != T_COMMENT && token_type != T_DOC_COMMENT
                && --need_tokens == 0
            ) {
                /* fetch the rest into a T_INLINE_HTML */
                if (zendcursor < zendlimit) {
                    add_token(
                        return_value, T_INLINE_HTML, zendcursor, zendlimit - zendcursor,
                        token_line, token_class, &interned_strings);
                }
                break;
            }
        } else if (token_type == T_HALT_COMPILER) {
            need_tokens = 3;
        }
 
        if (CG(increment_lineno)) {
            CG(zend_lineno)++;
            CG(increment_lineno) = 0;
        }
 
        token_line = CG(zend_lineno);
    }
 
    zval_ptr_dtor_str(&source_zval);
    zend_restore_lexical_state(&original_lex_state);
    zend_hash_destroy(&interned_strings);
 
    return 1;
}
 
struct event_context {
    zval *tokens;
    zend_class_entry *token_class;
};
 
static zval *extract_token_id_to_replace(zval *token_zv, const char *text, size_t length) {
    zval *id_zv, *text_zv;
    ZEND_ASSERT(token_zv);
    if (Z_TYPE_P(token_zv) == IS_ARRAY) {
        id_zv = zend_hash_index_find(Z_ARRVAL_P(token_zv), 0);
        text_zv = zend_hash_index_find(Z_ARRVAL_P(token_zv), 1);
    } else if (Z_TYPE_P(token_zv) == IS_OBJECT) {
        id_zv = OBJ_PROP_NUM(Z_OBJ_P(token_zv), 0);
        text_zv = OBJ_PROP_NUM(Z_OBJ_P(token_zv), 1);
    } else {
        return NULL;
    }
 
    /* There are multiple candidate tokens to which this feedback may apply,
     * check text to make sure this is the right one. */
    ZEND_ASSERT(Z_TYPE_P(text_zv) == IS_STRING);
    if (Z_STRLEN_P(text_zv) == length && !memcmp(Z_STRVAL_P(text_zv), text, length)) {
        return id_zv;
    }
    return NULL;
}
 
static void on_event(
        zend_php_scanner_event event, int token, int line,
        const char *text, size_t length, void *context)
{
    struct event_context *ctx = context;
 
    switch (event) {
        case ON_TOKEN:
            if (token == END) break;
            /* Special cases */
            if (token == ';' && LANG_SCNG(yy_leng) > 1) { /* ?> or ?>\n or ?>\r\n */
                token = T_CLOSE_TAG;
            } else if (token == T_ECHO && LANG_SCNG(yy_leng) == sizeof("<?=") - 1) {
                token = T_OPEN_TAG_WITH_ECHO;
            }
            add_token(
                ctx->tokens, token, (unsigned char *) text, length, line, ctx->token_class, NULL);
            break;
        case ON_FEEDBACK: {
            HashTable *tokens_ht = Z_ARRVAL_P(ctx->tokens);
            zval *token_zv, *id_zv = NULL;
            ZEND_HASH_REVERSE_FOREACH_VAL(tokens_ht, token_zv) {
                id_zv = extract_token_id_to_replace(token_zv, text, length);
                if (id_zv) {
                    break;
                }
            } ZEND_HASH_FOREACH_END();
            ZEND_ASSERT(id_zv);
            ZVAL_LONG(id_zv, token);
            break;
        }
        case ON_STOP:
            if (LANG_SCNG(yy_cursor) != LANG_SCNG(yy_limit)) {
                add_token(ctx->tokens, T_INLINE_HTML, LANG_SCNG(yy_cursor),
                    LANG_SCNG(yy_limit) - LANG_SCNG(yy_cursor), CG(zend_lineno),
                    ctx->token_class, NULL);
            }
            break;
    }
}
 
static bool tokenize_parse(
        zval *return_value, zend_string *source, zend_class_entry *token_class)
{
    zval source_zval;
    struct event_context ctx;
    zval token_stream;
    zend_lex_state original_lex_state;
    bool original_in_compilation;
    bool success;
 
    ZVAL_STR_COPY(&source_zval, source);
 
    original_in_compilation = CG(in_compilation);
    CG(in_compilation) = 1;
    zend_save_lexical_state(&original_lex_state);
 
    zend_prepare_string_for_scanning(&source_zval, ZSTR_EMPTY_ALLOC());
    array_init(&token_stream);
 
    ctx.tokens = &token_stream;
    ctx.token_class = token_class;
 
    CG(ast) = NULL;
    CG(ast_arena) = zend_arena_create(1024 * 32);
    LANG_SCNG(yy_state) = yycINITIAL;
    LANG_SCNG(on_event) = on_event;
    LANG_SCNG(on_event_context) = &ctx;
 
    if((success = (zendparse() == SUCCESS))) {
        ZVAL_COPY_VALUE(return_value, &token_stream);
    } else {
        zval_ptr_dtor(&token_stream);
    }
 
    zend_ast_destroy(CG(ast));
    zend_arena_destroy(CG(ast_arena));
 
    /* restore compiler and scanner global states */
    zend_restore_lexical_state(&original_lex_state);
    CG(in_compilation) = original_in_compilation;
 
    zval_ptr_dtor_str(&source_zval);
 
    return success;
}
 
static bool tokenize_common(
        zval *return_value, zend_string *source, zend_long flags, zend_class_entry *token_class)
{
    if (flags & TOKEN_PARSE) {
        return tokenize_parse(return_value, source, token_class);
    } else {
        int success = tokenize(return_value, source, token_class);
        /* Normal token_get_all() should not throw. */
        zend_clear_exception();
        return success;
    }
}
 
/* }}} */
 
/* {{{ */
PHP_FUNCTION(token_get_all)
{
    zend_string *source;
    zend_long flags = 0;
 
    ZEND_PARSE_PARAMETERS_START(1, 2)
        Z_PARAM_STR(source)
        Z_PARAM_OPTIONAL
        Z_PARAM_LONG(flags)
    ZEND_PARSE_PARAMETERS_END();
 
    if (!tokenize_common(return_value, source, flags, /* token_class */ NULL)) {
        RETURN_THROWS();
    }
}
/* }}} */
 
/* {{{ */
PHP_FUNCTION(token_name)
{
    zend_long type;
 
    ZEND_PARSE_PARAMETERS_START(1, 1)
        Z_PARAM_LONG(type)
    ZEND_PARSE_PARAMETERS_END();
 
    const char *token_name = get_token_type_name(type);
    if (!token_name) {
        token_name = "UNKNOWN";
    }
    RETURN_STRING(token_name);
}
/* }}} */