New command tmux-split

docs/commands/tmux-setup.md

@@ -3,8 +3,8 @@
 In the purpose of always making debugging sessions easier while being more effective, `GEF`
 integrates two commands:
 
-*  `tmux-setup`
-*  `screen-setup`
+- `tmux-setup`
+- `screen-setup`
 
 Those commands will check whether GDB is being spawn from inside a `tmux` (resp. `screen`) session,
 and if so, will split the pane vertically, and configure the context to be redirected to the new
@@ -22,6 +22,9 @@ gef➤ tmux-setup
 a very clean way to do this. Therefore, if possible, it would be recommended to use the `tmux-setup`
 command instead.
 
+For per-section pane splitting (each context section in its own pane), see
+[`gef tmux-split`](tmux-split.md).
+
 ### Possible color issues with tmux
 
 On Linux tmux only supports 8 colors with some terminal capabilities (`$TERM` environment variable).

docs/commands/tmux-split.md

@@ -0,0 +1,144 @@
+## Command `gef tmux-split`
+
+Splits the current `tmux` window so that each context section gets its own dedicated pane,
+similar to pwndbg's `splitmind` integration. This is more granular than
+[`tmux-setup`](tmux-setup.md), which redirects the entire context to a single side pane.
+
+### Usage
+
+```text
+gef tmux-split [SECTION ...] [--layout LAYOUT | --layout-file PATH] [--reset]
+```
+
+Three modes:
+
+1. **Flat** — `gef tmux-split [SECTION ...]` spawns one pane per section and applies a
+   tmux layout name. With no section arguments the default set is `regs stack code`.
+   Sections: `legend`, `regs`, `stack`, `code`, `args`, `memory`, `source`, `trace`,
+   `threads`, `extra`. Layout names (`--layout`): `tiled` (default),
+   `main-vertical`, `main-horizontal`, `even-horizontal`, `even-vertical`.
+
+2. **Built-in tree layout** — `gef tmux-split --layout pwndbg-classic` reproduces
+   pwndbg's default splitmind arrangement: `code` on top (60%), `regs`/`stack`/`trace`
+   tiled across the bottom row.
+
+3. **User-defined tree** — `gef tmux-split --layout-file <path.ini>` loads an arbitrary
+   layout tree (see [Layout file format](#layout-file-format) below).
+
+`--reset` clears every per-section redirect, kills the panes that GEF spawned, and
+collapses back to single-pane mode.
+
+### Examples
+
+Default split (regs / stack / code each in their own pane):
+
+```text
+gef➤ gef tmux-split
+```
+
+Split only `regs` and `stack`, arranged vertically:
+
+```text
+gef➤ gef tmux-split regs stack --layout main-vertical
+```
+
+Reproduce pwndbg's classic splitmind layout (code on top, regs/stack/trace below):
+
+```text
+gef➤ gef tmux-split --layout pwndbg-classic
+```
+
+Use a custom layout file:
+
+```text
+gef➤ gef tmux-split --layout-file ~/.config/gef/layout.ini
+```
+
+Tear it all down:
+
+```text
+gef➤ gef tmux-split --reset
+```
+
+### Layout file format
+
+Layout files are INI (parsed via Python's stdlib `configparser`). The format is **flat**
+and modeled on splitmind: each pane positions itself relative to a previously declared
+pane (or `main`, the user's GDB pane) using one of `right` / `left` / `above` / `below`.
+
+```ini
+[layout]
+panes = regs, stack, code, trace      ; spawn order matters
+
+[pane.regs]
+section = regs                ; defaults to the pane name if omitted
+direction = right             ; right | left | above | below
+relative_to = main            ; references `main` or any pane declared earlier
+size = 50%                    ; size of THIS new pane (% or raw cells/rows); optional
+
+[pane.stack]
+direction = below
+relative_to = regs
+size = 75%
+
+[pane.code]
+direction = below
+relative_to = stack
+size = 66%
+
+[pane.trace]
+direction = below
+relative_to = code
+size = 50%
+```
+
+Rules:
+
+* `[layout].panes` lists pane names in spawn order.
+* Each `[pane.<name>]` declares one pane.
+* `direction` is required and must be one of `right`, `left`, `above`, `below`.
+* `relative_to` defaults to `main`. It must reference `main` or a pane declared **earlier**
+  in the `panes` list.
+* `section` defaults to the pane name; both must be a valid section name.
+* `size` is optional. Accepts `<N>%` or raw cells/rows (`<N>`); omit for tmux's default
+  even split.
+* The same section cannot be bound by more than one pane.
+* Errors abort the split before any pane is spawned, with a clear message.
+
+### Generating a starter file
+
+To get a working file you can edit, dump the built-in:
+
+```text
+gef➤ gef tmux-split --dump-layout pwndbg-classic ~/.config/gef/layout.ini
+```
+
+Then load it after editing:
+
+```text
+gef➤ gef tmux-split --layout-file ~/.config/gef/layout.ini
+```
+
+### How it works
+
+For each requested section, `gef tmux-split` spawns a tmux pane that publishes its tty
+path to a temp file, then sleeps. GEF reads the tty path and writes it into the
+`context.output.<section>` setting. From that point on, `ContextCommand` renders that
+section directly into the dedicated pane's tty rather than into the main context stream.
+
+The `context.output.<section>` settings are also writable directly — set one to a tty
+path you control to route a section anywhere (e.g. another terminal, a fifo). An empty
+value (the default) restores normal main-stream rendering for that section.
+
+### Cleanup
+
+Spawned panes are tracked in `gef.session.tmux_panes` and killed automatically:
+
+* on GDB exit (via `atexit`),
+* when `gef tmux-split --reset` is invoked,
+* when the section's tty disappears mid-session — GEF clears the redirect and recovers.
+
+### Requirements
+
+* You must already be inside a `tmux` session (`$TMUX` set).
+* The `tmux` binary must be in `$PATH`.