(37a72b0150ec36b4ea27175039afc28c62207b0c)

Routines to manipulate encodings of strings. More...

#include "ruby/internal/dllexport.h"
#include "ruby/internal/value.h"
#include "ruby/internal/encoding/encoding.h"
#include "ruby/internal/attr/nonnull.h"
#include "ruby/internal/intern/string.h"

Include dependency graph for string.h:

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Functions
VALUE	rb_enc_str_new (const char ptr, long len, rb_encoding enc)
	Identical to rb_str_new(), except it additionally takes an encoding. More...

VALUE	rb_enc_str_new_cstr (const char ptr, rb_encoding enc)
	Identical to rb_enc_str_new(), except it assumes the passed pointer is a pointer to a C string. More...

VALUE	rb_enc_str_new_static (const char ptr, long len, rb_encoding enc)
	Identical to rb_enc_str_new(), except it takes a C string literal. More...

VALUE	rb_enc_interned_str (const char ptr, long len, rb_encoding enc)
	Identical to rb_enc_str_new(), except it returns a "f"string. More...

VALUE	rb_enc_interned_str_cstr (const char ptr, rb_encoding enc)
	Identical to rb_enc_str_new_cstr(), except it returns a "f"string. More...

long	rb_enc_strlen (const char head, const char tail, rb_encoding *enc)
	Counts the number of characters of the passed string, according to the passed encoding. More...

char *	rb_enc_nth (const char head, const char tail, long nth, rb_encoding *enc)
	Queries the n-th character. More...

VALUE	rb_obj_encoding (VALUE obj)
	Identical to rb_enc_get_index(), except the return type. More...

VALUE	rb_enc_str_buf_cat (VALUE str, const char ptr, long len, rb_encoding enc)
	Identical to rb_str_cat(), except it additionally takes an encoding. More...

VALUE	rb_enc_uint_chr (unsigned int code, rb_encoding *enc)
	Encodes the passed code point into a series of bytes. More...

VALUE	rb_external_str_new_with_enc (const char ptr, long len, rb_encoding enc)
	Identical to rb_external_str_new(), except it additionally takes an encoding. More...

VALUE	rb_str_export_to_enc (VALUE obj, rb_encoding *enc)
	Identical to rb_str_export(), except it additionally takes an encoding. More...

VALUE	rb_str_conv_enc (VALUE str, rb_encoding from, rb_encoding to)
	Encoding conversion main routine. More...

VALUE	rb_str_conv_enc_opts (VALUE str, rb_encoding from, rb_encoding to, int ecflags, VALUE ecopts)
	Identical to rb_str_conv_enc(), except it additionally takes IO encoder options. More...

int	rb_enc_str_coderange (VALUE str)
	Scans the passed string to collect its code range. More...

long	rb_str_coderange_scan_restartable (const char str, const char end, rb_encoding enc, int cr)
	Scans the passed string until it finds something odd. More...

int	rb_enc_str_asciionly_p (VALUE str)
	Queries if the passed string is "ASCII only". More...

long	rb_memsearch (const void x, long m, const void y, long n, rb_encoding *enc)
	Looks for the passed string in the passed buffer. More...

Detailed Description

Routines to manipulate encodings of strings.

Author: Ruby developers ruby-.nosp@m.core.nosp@m.@ruby.nosp@m.-lan.nosp@m.g.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.

Definition in file string.h.

Function Documentation

◆ rb_enc_interned_str()

VALUE rb_enc_interned_str	(	const char *	ptr,
		long	len,
		rb_encoding *	enc
	)

Identical to rb_enc_str_new(), except it returns a "f"string.

It can also be seen as a routine identical to rb_interned_str(), except it additionally takes an encoding.

Parameters

[in]	ptr	A memory region of `len` bytes length.
[in]	len	Length of `ptr`, in bytes, not including the terminating NUL character.
[in]	enc	Encoding of `ptr`.

Exceptions

rb_eArgError len is negative.

Returns: A found or created instance of rb_cString, of len bytes length, of enc encoding, whose contents are identical to that of ptr.

Precondition: At least len bytes of continuous memory region shall be accessible via ptr.

Note: enc can be a null pointer.

Definition at line 12521 of file string.c.

Referenced by rb_enc_interned_str_cstr().

◆ rb_enc_interned_str_cstr()

VALUE rb_enc_interned_str_cstr	(	const char *	ptr,
		rb_encoding *	enc
	)

Identical to rb_enc_str_new_cstr(), except it returns a "f"string.

It can also be seen as a routine identical to rb_interned_str_cstr(), except it additionally takes an encoding.

Parameters

[in]	ptr	A memory region of `len` bytes length.
[in]	enc	Encoding of `ptr`.

Returns: A found or created instance of rb_cString of enc encoding, whose contents are identical to that of ptr.

Precondition: At least len bytes of continuous memory region shall be accessible via ptr.

Note: enc can be a null pointer.

Definition at line 12543 of file string.c.

◆ rb_enc_nth()

char* rb_enc_nth	(	const char *	head,
		const char *	tail,
		long	nth,
		rb_encoding *	enc
	)

Queries the n-th character.

Like rb_enc_strlen() this function can be fast or slow depending on the contents. Don't expect characters to be uniformly distributed across the entire string.

Parameters

[in]	head	Leftmost pointer to the string.
[in]	tail	Rightmost pointer to the string.
[in]	nth	Requested index of characters.
[in]	enc	Encoding of the string.

Returns: Pointer to the first byte of the character that is nth character ahead of head, or tail if there is no such character (OOB etc). The definition of "character" depends on the passed enc.

Definition at line 2930 of file string.c.

Referenced by rb_str_ellipsize(), and rb_str_format().

◆ rb_enc_str_asciionly_p()

int rb_enc_str_asciionly_p ( VALUE str )

Queries if the passed string is "ASCII only".

An ASCII only string is a string who doesn't have any non-ASCII characters at all. This doesn't necessarily mean the string is in ASCII encoding. For instance a String of CP932 encoding can quite much be ASCII only, depending on its contents.

Parameters

[in] str String in question.

Return values

1	It doesn't have non-ASCII characters.
0	It has characters that are out of ASCII.

Definition at line 919 of file string.c.

Referenced by rb_inspect(), and rb_reg_quote().

◆ rb_enc_str_buf_cat()

VALUE rb_enc_str_buf_cat	(	VALUE	str,
		const char *	ptr,
		long	len,
		rb_encoding *	enc
	)

Identical to rb_str_cat(), except it additionally takes an encoding.

Parameters

[out]	str	Destination object.
[in]	ptr	Contents to append.
[in]	len	Length of `src`, in bytes.
[in]	enc	Encoding of `ptr`.

Exceptions

rb_eArgError	`len` is negative.
rb_eEncCompatError	`enc` is not compatible with `str`.

Returns: The passed dst.

Postcondition: The contents of ptr is copied, transcoded into dst's encoding, then pasted into dst's end.

Definition at line 3612 of file string.c.

Referenced by rb_reg_regsub().

◆ rb_enc_str_coderange()

int rb_enc_str_coderange ( VALUE str )

Scans the passed string to collect its code range.

Because a Ruby's string is mutable, its contents change from time to time; so does its code range. A long-lived string tends to fall back to RUBY_ENC_CODERANGE_UNKNOWN. This API scans it and re-assigns a fine-grained code range constant.

Parameters

[out] str A string.

Returns: An enum ruby_coderange_type.

Definition at line 900 of file string.c.

Referenced by rb_econv_append(), rb_str_buf_append(), and rb_str_comparable().

◆ rb_enc_str_new()

VALUE rb_enc_str_new	(	const char *	ptr,
		long	len,
		rb_encoding *	enc
	)

Identical to rb_str_new(), except it additionally takes an encoding.

Parameters

[in]	ptr	A memory region of `len` bytes length.
[in]	len	Length of `ptr`, in bytes, not including the terminating NUL character.
[in]	enc	Encoding of `ptr`.

Exceptions

rb_eNoMemError	Failed to allocate `len+1` bytes.
rb_eArgError	`len` is negative.

Returns: An instance of rb_cString, of len bytes length, of enc encoding, whose contents are verbatim copy of ptr.

Precondition: At least len bytes of continuous memory region shall be accessible via ptr.

Note: enc can be a null pointer. It can also be seen as a routine identical to rb_usascii_str_new() then.

Definition at line 1068 of file string.c.

Referenced by rb_enc_str_new_cstr(), rb_enc_uint_chr(), rb_external_str_new_with_enc(), and rb_intern3().

◆ rb_enc_str_new_cstr()

VALUE rb_enc_str_new_cstr	(	const char *	ptr,
		rb_encoding *	enc
	)

Identical to rb_enc_str_new(), except it assumes the passed pointer is a pointer to a C string.

It can also be seen as a routine identical to rb_str_new_cstr(), except it additionally takes an encoding.

Parameters

[in]	ptr	A C string.
[in]	enc	Encoding of `ptr`.

Exceptions

rb_eNoMemError Failed to allocate memory.

Returns: An instance of rb_cString, of enc encoding, whose contents are verbatim copy of ptr.

Precondition: ptr must not be a null pointer.; Because ptr is a C string it makes no sense for enc to be something like UTF-32.

Note: enc can be a null pointer. It can also be seen as a routine identical to rb_usascii_str_new_cstr() then.

Definition at line 1098 of file string.c.

Referenced by rb_usascii_str_new_cstr(), and rb_utf8_str_new_cstr().

◆ rb_enc_str_new_static()

VALUE rb_enc_str_new_static	(	const char *	ptr,
		long	len,
		rb_encoding *	enc
	)

Identical to rb_enc_str_new(), except it takes a C string literal.

It can also be seen as a routine identical to rb_str_new_static(), except it additionally takes an encoding.

Parameters

[in]	ptr	A C string literal.
[in]	len	`strlen(ptr)`.
[in]	enc	Encoding of `ptr`.

Exceptions

rb_eArgError len out of range of size_t.

Precondition: ptr must be a C string constant.

Returns: An instance of rb_cString, of enc encoding, whose backend storage is the passed C string literal.

Warning: It is a very bad idea to write to a C string literal (often immediate SEGV shall occur). Consider return values of this function be read-only.

Note: enc can be a null pointer. It can also be seen as a routine identical to rb_usascii_str_new_static() then.

Definition at line 1150 of file string.c.

◆ rb_enc_strlen()

long rb_enc_strlen	(	const char *	head,
		const char *	tail,
		rb_encoding *	enc
	)

Counts the number of characters of the passed string, according to the passed encoding.

This has to be complicated. The passed string could be invalid and/or broken. This routine would scan from the beginning til the end, byte by byte, to seek out character boundaries. Could be super slow.

Parameters

[in]	head	Leftmost pointer to the string.
[in]	tail	Rightmost pointer to the string.
[in]	enc	Encoding of the string.

Returns: Number of characters exist in head .. tail. The definition of "character" depends on the passed enc.

Definition at line 2260 of file string.c.

Referenced by rb_str_format().

◆ rb_enc_uint_chr()

VALUE rb_enc_uint_chr	(	unsigned int	code,
		rb_encoding *	enc
	)

Encodes the passed code point into a series of bytes.

Parameters

[in]	code	Code point.
[in]	enc	Target encoding scheme.

Exceptions

rb_eRangeError enc does not glean code.

Returns: An instance of rb_cString, of enc encoding, whose sole contents is code represented in enc.

Note: No way to encode code points bigger than UINT_MAX.

Definition at line 3803 of file numeric.c.

Referenced by rb_io_ungetc().

◆ rb_external_str_new_with_enc()

VALUE rb_external_str_new_with_enc	(	const char *	ptr,
		long	len,
		rb_encoding *	enc
	)

Identical to rb_external_str_new(), except it additionally takes an encoding.

However the whole point of rb_external_str_new() is to encode a string into default external encoding. Being able to specify arbitrary encoding just ruins the designed purpose the function meseems.

Parameters

[in]	ptr	A memory region of `len` bytes length.
[in]	len	Length of `ptr`, in bytes, not including the terminating NUL character.
[in]	enc	Target encoding scheme.

Exceptions

rb_eArgError len is negative.

Returns: An instance of rb_cString. In case encoding conversion from "default internal" to enc is fully defined over the given contents, then the return value is a string of enc encoding, whose contents are the converted ones. Otherwise the string is a junk.

Warning: It doesn't raise on a conversion failure and silently ends up in a corrupted output. You can know the failure by querying valid_encoding? of the result object.

Definition at line 1291 of file string.c.

Referenced by rb_external_str_new(), rb_external_str_new_cstr(), rb_filesystem_str_new(), rb_filesystem_str_new_cstr(), rb_locale_str_new(), and rb_locale_str_new_cstr().

◆ rb_memsearch()

long rb_memsearch	(	const void *	x,
		long	m,
		const void *	y,
		long	n,
		rb_encoding *	enc
	)

Looks for the passed string in the passed buffer.

Parameters

[in]	x	Query string.
[in]	m	Number of bytes of `x`.
[in]	y	Buffer that potentially includes `x`.
[in]	n	Number of bytes of `y`.
[in]	enc	Encoding of both `x` and `y`.

Return values

-1	Not found.
otherwise	Found index in `y`.

Note: This API can match at a non-character-boundary.

Definition at line 252 of file re.c.

◆ rb_obj_encoding()

VALUE rb_obj_encoding ( VALUE obj )

Identical to rb_enc_get_index(), except the return type.

Parameters

[in] obj Object in question.

Exceptions

rb_eTypeError obj is incapable of having an encoding.

Returns: obj's encoding.

Definition at line 1163 of file encoding.c.

◆ rb_str_coderange_scan_restartable()

long rb_str_coderange_scan_restartable	(	const char *	str,
		const char *	end,
		rb_encoding *	enc,
		int *	cr
	)

Scans the passed string until it finds something odd.

Returns the number of bytes scanned. As the name implies this is suitable for repeated call. One of its application is IO#readlines. The method reads from its receiver's read buffer, maybe more than once, looking for newlines. But "newline" can be different among encodings. This API is used to detect broken contents to properly mark them as such.

Parameters

[in]	str	String to scan.
[in]	end	End of `str`.
[in]	enc	`str`'s encoding.
[out]	cr	Return buffer.

Returns: Distance between str and first such byte where broken.

Postcondition: cr has the code range type.

Definition at line 784 of file string.c.

Referenced by rb_econv_append(), and rb_str_set_len().

◆ rb_str_conv_enc()

VALUE rb_str_conv_enc	(	VALUE	str,
		rb_encoding *	from,
		rb_encoding *	to
	)

Encoding conversion main routine.

Parameters

[in]	str	String to convert.
[in]	from	Source encoding.
[in]	to	Destination encoding.

Returns: A copy of str, with conversion from from to to applied.

Note: from can be a null pointer. str's encoding is taken then.; to can be a null pointer. No-op then.

Definition at line 1285 of file string.c.

Referenced by rb_dir_getwd(), rb_str_encode_ospath(), and rb_str_export_to_enc().

◆ rb_str_conv_enc_opts()

VALUE rb_str_conv_enc_opts	(	VALUE	str,
		rb_encoding *	from,
		rb_encoding *	to,
		int	ecflags,
		VALUE	ecopts
	)

Identical to rb_str_conv_enc(), except it additionally takes IO encoder options.

The extra arguments can be constructed using io_extract_modeenc() etc.

Parameters

[in]	str	String to convert.
[in]	from	Source encoding.
[in]	to	Destination encoding.
[in]	ecflags	A set of enum ruby_econv_flag_type.
[in]	ecopts	Optional hash.

Returns: A copy of str, with conversion from from to to applied.

Note: from can be a null pointer. str's encoding is taken then.; to can be a null pointer. No-op then.; ecopts can be RUBY_Qnil, which is equivalent to passing an empty hash.

Definition at line 1169 of file string.c.

Referenced by rb_str_conv_enc().

◆ rb_str_export_to_enc()

VALUE rb_str_export_to_enc	(	VALUE	obj,
		rb_encoding *	enc
	)

Identical to rb_str_export(), except it additionally takes an encoding.

Parameters

[in]	obj	Target object.
[in]	enc	Target encoding.

Exceptions

rb_eTypeError No implicit conversion to String.

Returns: Converted ruby string of enc encoding.

Definition at line 1390 of file string.c.

Referenced by rb_str_export(), and rb_str_export_locale().

(37a72b0150ec36b4ea27175039afc28c62207b0c)

Functions

Detailed Description

Function Documentation

◆ rb_enc_interned_str()

◆ rb_enc_interned_str_cstr()

◆ rb_enc_nth()

◆ rb_enc_str_asciionly_p()

◆ rb_enc_str_buf_cat()

◆ rb_enc_str_coderange()

◆ rb_enc_str_new()

◆ rb_enc_str_new_cstr()

◆ rb_enc_str_new_static()

◆ rb_enc_strlen()

◆ rb_enc_uint_chr()

◆ rb_external_str_new_with_enc()

◆ rb_memsearch()

◆ rb_obj_encoding()

◆ rb_str_coderange_scan_restartable()

◆ rb_str_conv_enc()

◆ rb_str_conv_enc_opts()

◆ rb_str_export_to_enc()