Tavmjong: Created page with "Filenames should be std::strings but presented as Glib::ustings (UTF8) in GUI elements. Glib has functions to convert back and forth. All Glib file utility functions take and..."

2023-10-10T11:15:36Z

Created page with "Filenames should be std::strings but presented as Glib::ustings (UTF8) in GUI elements. Glib has functions to convert back and forth. All Glib file utility functions take and..."

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Filenames should be std::strings but presented as Glib::ustings (UTF8) in GUI elements. Glib has functions to convert back and forth. All Glib file utility functions take and return std::strings (other than those converting between types). We use these functions throughout our code, often ignoring implicit conversions between std::string and Glib::ustring (or UTF8 encoded and not-encoded strings of type char*).

== Gtk4 Changes ==

Gtk4 makes several changes that impact our use of strings:

=== Use of Glib::StdStringView and Glib::UStringView ===

Many functions take these types as arguments. It's an error to mix them.

# Glib::StdStringView : Different from std::string_view in that only holds null-terminated strings. One can pass in a Glib::ustring via Glib::ustring::c_str().
# Glib::UStringView : UTF8 encoded string. One can pass in a std::string using std::string::c_str().

=== Return Gio::File rather than filenames (std::strings) in File dialogs ===

Gio::Files handle std::string/Glib::ustrings properly. We should be using them and have some code that already does.

== Updating Our Code ==

This is quite messy. Our code file handling code is divided over many file:

* src/file.h: Several file opening functions (that should be removed). Calls document_new in inkscape-application.h. Also contains Import dialog (should be moved). Calls Extension::Open.
* src/inkscape-application.h: Functions for opening documents and creating windows. Calls ink_file_new, ink_file_open(data), ink_file_open(Gio::File) in io/file.h.
* src/io/file.h: Functions ink_file_new, ink_file_open. Calls SPDocument::createNewDoc() or SPDocument::createNewDocFromMem() in src/document.h
* src/document.h: Functions for creating documents by first creating the XML via calling sp_rper_read_file(filename, SP_SVG_NS_URI), sp_repr_document_new("svg:svg"), sp_repr_read_mem(char const* buffer...)
* src/xml/repr.h (repr-io.cpp): Functions that use libxml2 to extract out the XML tree from files.

* src/extension/internal/xxx: Functions to open various file types.
* src/extension/internal.svg.h: Open SVG files: calls functions in src/document.h.

* src/io/sys.h: Various functions that assume filenames are in UTF8. Most functions in this file should be removed.

Filenames - Revision history

Tavmjong: Created page with "Filenames should be std::strings but presented as Glib::ustings (UTF8) in GUI elements. Glib has functions to convert back and forth. All Glib file utility functions take and..."