147 lines
5.3 KiB
C++
147 lines
5.3 KiB
C++
#ifndef RBIMPL_RMATCH_H /*-*-C++-*-vi:se ft=cpp:*/
|
|
#define RBIMPL_RMATCH_H
|
|
/**
|
|
* @file
|
|
* @author Ruby developers <ruby-core@ruby-lang.org>
|
|
* @copyright This file is a part of the programming language Ruby.
|
|
* Permission is hereby granted, to either redistribute and/or
|
|
* modify this file, provided that the conditions mentioned in the
|
|
* file COPYING are met. Consult the file for details.
|
|
* @warning Symbols prefixed with either `RBIMPL` or `rbimpl` are
|
|
* implementation details. Don't take them as canon. They could
|
|
* rapidly appear then vanish. The name (path) of this header file
|
|
* is also an implementation detail. Do not expect it to persist
|
|
* at the place it is now. Developers are free to move it anywhere
|
|
* anytime at will.
|
|
* @note To ruby-core: remember that this header can be possibly
|
|
* recursively included from extension libraries written in C++.
|
|
* Do not expect for instance `__VA_ARGS__` is always available.
|
|
* We assume C99 for ruby itself but we don't assume languages of
|
|
* extension libraries. They could be written in C++98.
|
|
* @brief Defines struct ::RMatch.
|
|
*/
|
|
#include "ruby/internal/attr/artificial.h"
|
|
#include "ruby/internal/attr/pure.h"
|
|
#include "ruby/internal/cast.h"
|
|
#include "ruby/internal/core/rbasic.h"
|
|
#include "ruby/internal/value.h"
|
|
#include "ruby/internal/value_type.h"
|
|
#include "ruby/assert.h"
|
|
|
|
/**
|
|
* Convenient casting macro.
|
|
*
|
|
* @param obj An object, which is in fact an ::RMatch.
|
|
* @return The passed object casted to ::RMatch.
|
|
*/
|
|
#define RMATCH(obj) RBIMPL_CAST((struct RMatch *)(obj))
|
|
/** @cond INTERNAL_MACRO */
|
|
#define RMATCH_REGS RMATCH_REGS
|
|
/** @endcond */
|
|
|
|
struct re_patter_buffer; /* a.k.a. OnigRegexType, defined in onigmo.h */
|
|
struct re_registers; /* Also in onigmo.h */
|
|
|
|
/**
|
|
* @old{re_pattern_buffer}
|
|
*
|
|
* @internal
|
|
*
|
|
* @shyouhei wonders: is anyone actively using this typedef ...?
|
|
*/
|
|
typedef struct re_pattern_buffer Regexp;
|
|
|
|
/**
|
|
* Represents the region of a capture group. This is basically for caching
|
|
* purpose. re_registers have similar concepts (`beg` and `end`) but they are
|
|
* in `ptrdiff_t*`. In order for us to implement `MatchData#offset` that info
|
|
* has to be converted to offset integers. This is the struct to hold such
|
|
* things.
|
|
*
|
|
* @internal
|
|
*
|
|
* But why on earth it has to be visible from extension libraries?
|
|
*/
|
|
struct rmatch_offset {
|
|
long beg; /**< Beginning of a group. */
|
|
long end; /**< End of a group. */
|
|
};
|
|
|
|
/** Represents a match. */
|
|
struct rmatch {
|
|
/**
|
|
* "Registers" of a match. This is a quasi-opaque struct that holds
|
|
* execution result of a match. Roughly resembles `&~`.
|
|
*/
|
|
struct re_registers regs;
|
|
|
|
/** Capture group offsets, in C array. */
|
|
struct rmatch_offset *char_offset;
|
|
|
|
/** Number of ::rmatch_offset that ::rmatch::char_offset holds. */
|
|
int char_offset_num_allocated;
|
|
};
|
|
|
|
/**
|
|
* Regular expression execution context. When a regular expression "matches"
|
|
* to a string, it generates capture groups etc. This struct holds that info.
|
|
* Visible from Ruby as an instance of `MatchData`.
|
|
*
|
|
* @note There is no way for extension libraries to manually generate this
|
|
* struct except by actually exercising the match operation of a regular
|
|
* expression.
|
|
*/
|
|
struct RMatch {
|
|
|
|
/** Basic part, including flags and class. */
|
|
struct RBasic basic;
|
|
|
|
/**
|
|
* The target string that the match was made against.
|
|
*/
|
|
VALUE str;
|
|
|
|
/**
|
|
* The result of this match.
|
|
*/
|
|
struct rmatch *rmatch;
|
|
|
|
/**
|
|
* The expression of this match.
|
|
*/
|
|
VALUE regexp; /* RRegexp */
|
|
};
|
|
|
|
RBIMPL_ATTR_PURE_UNLESS_DEBUG()
|
|
RBIMPL_ATTR_ARTIFICIAL()
|
|
/**
|
|
* Queries the raw ::re_registers.
|
|
*
|
|
* @param[in] match A match object
|
|
* @pre `match` must be of ::RMatch.
|
|
* @return Its execution result.
|
|
* @note Good. So you are aware of the fact that it could return NULL.
|
|
* Yes. It actually does. This is a really bizarre thing. The
|
|
* situation is about `String#gsub` and its family. They take
|
|
* strings as arguments, like `"foo".sub("bar", "baz")`. On such
|
|
* situations, in order to optimise memory allocations, these
|
|
* methods do not involve regular expressions at all. They just
|
|
* sequentially scan the receiver. Okay. The story begins here.
|
|
* Even when they do not kick our regexp engine, there must be
|
|
* backref objects e.g. `$&`. But how? You know what? Ruby fakes
|
|
* them. It allocates an empty ::RMatch and behaves as if there
|
|
* were execution contexts. In reality there weren't. No
|
|
* ::re_registers are allocated then. There is no way for this
|
|
* function but to return NULL for those fake ::RMatch. This is
|
|
* the reason for the nullability of this function.
|
|
*/
|
|
static inline struct re_registers *
|
|
RMATCH_REGS(VALUE match)
|
|
{
|
|
RBIMPL_ASSERT_TYPE(match, RUBY_T_MATCH);
|
|
RBIMPL_ASSERT_OR_ASSUME(RMATCH(match)->rmatch != NULL);
|
|
return &RMATCH(match)->rmatch->regs;
|
|
}
|
|
|
|
#endif /* RBIMPL_RMATCH_H */
|