Selene Browser

Selene — the NyxOS web browser

Selene is a web browser written as a kernel window (kernel/selene_win.c). It fetches real pages over HTTP and HTTPS, parses the HTML itself, lays it out as text with headings, lists, tables and inline images, and lets you follow links, submit forms, search the page, and keep several tabs open.

It is named after the moon, like the rest of NyxOS.

See also: Cryptography and TLS, Networking Stack, Image Decoders, GUI Subsystem, Desktop Applications

Opening it

• Click the Selene desktop icon
• Or run selene from the shell

The window has a toolbar (back button and URL box), a tab strip, the page view, and a status line.

What it does

Capability	Detail
HTTP	http_get(), which drives the network itself and runs DHCP first if there is no lease
HTTPS	Full TLS 1.2 with certificate verification — see Cryptography and TLS
Streaming receive	Pages larger than the record buffer load correctly
Links	<a href> rendered coloured and underlined; relative and root-relative hrefs resolved against the current page
History	32-deep Back stack per tab
Tabs	Up to 6 per window, with a [+] new-tab button
Forms	GET and POST, application/x-www-form-urlencoded
Tables	<table> laid out as aligned, bordered columns
Images	PNG, BMP and GIF fetched, decoded and drawn inline
Find in page	Ctrl+F, with match counting and navigation
Text structure	Headings, paragraphs, lists and horizontal rules

Controls

Input	Action
Type in the URL box, Enter	Load the URL
Tab / Shift+Tab	Move the selection between links and form fields
Enter	Follow the selected link, submit the focused form, or load the URL bar if nothing is selected
Click	Follow the link, or focus the field, under the cursor
Backspace	Go back
Ctrl+F	Open the find bar; type a query, and matches are counted and highlighted
Scroll / arrows	Move through the page

Tab order runs through the URL bar, then the page's links and fields by position, then back to the URL bar — so a search box a few tabs into a page is reachable without the mouse.

Rendering

Selene is a text-layout browser, not a CSS engine. HTML is parsed directly:

• <script> and <style> contents are dropped
• Tags are stripped, common entities decoded, <title> extracted for the tab label
• Block elements (<h1>–<h6>, <p>, <li>, <hr>) produce structure — headings stand out, lists are bulleted, rules are drawn
• Text is word-wrapped to 86 columns
• <table> cells are measured and drawn as aligned columns with borders
• <img> renders as a framed box; once the image is fetched and decoded, the picture is drawn in place. An image that cannot be fetched or decoded keeps its box, showing the alt text or the filename

Images

Fetching every image on a page would make a page load feel broken, so loading is lazy and progressive: the text renders immediately and only the images you can actually see are downloaded, decoding into place as they arrive.

Limit	Value
<img> elements tracked per page	128
Images fetched and decoded per page load	8
Per-image download buffer	512 KB

Decoding is handled by Image Decoders — PNG (via DEFLATE), BMP and GIF (via LZW).

Forms

<form action="/search" method="get">
  <input type="text" name="q">
  <input type="submit" value="Go">
</form>

Control kind	Handling
text, search, email, url, password, tel, number	Editable box, 22 columns wide
submit, <button>	Submit button
hidden	Carried into the submission, not shown

GET builds a query string onto the action URL; POST sends the encoded body with a Content-Length through tls_https_request(). formtest is the kernel-shell self-test for form parsing and URL building.

Limits

Setting	Value
Rendered lines per page	1200
Line width	96 columns (wrapped at 86)
Links per page	240
Forms / fields per page	16 / 64
Tabs per window	6
Back history per tab	32

Beyond those: no JavaScript, no CSS, no video or audio, no cookies, no persistent cache.

History

Selene first fetched and rendered a real page in v5.9.44. Links and Back followed in v5.9.45, document structure in v5.9.47. HTTPS arrived in v5.9.56 on top of the TLS arc, then forms (v5.9.68–v5.9.69), find-in-page (v5.9.75), image placeholders (v5.9.76), tables (v5.9.77), tabs (v5.9.78), and real inline images (v5.9.83–v5.9.86). See Version History.

See also

• Cryptography and TLS - the HTTPS layer
• Image Decoders - how <img> becomes pixels
• Networking Stack - the HTTP client underneath
• GUI Subsystem - the window it runs in

External resources

• HTML Living Standard - WHATWG
• RFC 9110 - HTTP Semantics - IETF
• URL Living Standard - WHATWG