.clang-format

+---
+BasedOnStyle: Google
+IndentWidth: 4
+IncludeBlocks: Preserve
+Cpp11BracedListStyle: false

.clang-tidy

+# Don't care about deprecated APIs (noisy) and about memcpy/strcpy (we'll fix
+# that later).
+Checks: '-clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling,-clang-diagnostic-deprecated-declarations'

.gitignore

+# esp-idf
+sdkconfig.old
+sdkconfig
+dependencies.lock
+build
+
+.sdkconfig.defaults.generated
+
+# micropython
+__pycache__
+
+# editor crud
+.vscode
+*swp
+*~
+
+# Python
+.venv
+/venv/
+
+# sphinx
+docs/_build/
+
+/tools/mypy.sh
+
+# bl00mbox docs
+components/bl00mbox/docs/
+components/bl00mbox/public/

.gitlab-ci.yml

+stages:
+  - check
+  - build
+  - deploy
+
+variables:
+  GIT_SUBMODULE_STRATEGY: recursive
+  GIT_DEPTH: 0
+
+default:
+  # built via:
+  #     docker load < $(nix-build nix/docker-image.nix)
+  image: registry.gitlab.com/flow3r-badge/flow3r-build:238576xsg79mjr2bkqg106qisvd3b5q9
+
+clang-tidy:
+  stage: check
+  script:
+    - "bash tools/clang-tidy.sh"
+    - "python3 tools/codequal-report.py clang-tidy warnings.txt > cqual.json"
+  artifacts:
+    when: always
+    reports:
+      codequality: cqual.json
+
+format:
+  stage: check
+  script:
+    - "git clean -fdx"
+    - "bash tools/format.sh"
+    - "[ -z \"$(git status --porcelain)\" ] || (echo 'Differences found, please run tools/format.sh.' && git diff HEAD && exit 1)"
+
+build:
+  stage: build
+  script:
+    - idf.py -g c23 build size
+  artifacts:
+    expose_as: 'firmware'
+    paths: ['build/flow3r.bin']
+    expire_in: 5 hours
+
+build_recovery:
+  stage: build
+  script:
+    - cd recovery
+    - idf.py build size
+  artifacts:
+    expose_as: 'Recovery'
+    paths: ['recovery/build/flow3r-recovery.bin', 'recovery/build/partition_table/partition-table.bin', 'recovery/build/bootloader/bootloader.bin']
+    expire_in: 5 hours
+
+simulate:
+  stage: build
+  script:
+    - python3 sim/run.py --screenshot
+  artifacts:
+    expose_as: 'Simulator Screenshot'
+    paths: ['flow3r.png']
+    expire_in: 5 hours
+
+pages:
+  stage: deploy
+  rules:
+    - if: $CI_COMMIT_BRANCH == "main"
+  script:
+    - git tag | xargs git tag -d
+    - git checkout origin/main
+    - git checkout -b dev
+    - git branch --all
+    - git branch --all | sed -e 's/..//' | grep '^remotes/origin/release/' | while read b; do git checkout -b "v${b#remotes/origin/release/}" "$b"; done
+    - git checkout dev
+    - git branch
+    - mkdir public
+    - cd docs
+    - make versionedhtml
+    - cp -r _build/$(git branch --sort=version:refname | tail -n1 | sed -e 's/..//')/* _build/
+    - python redirects.py
+    - cp -r _build/* ../public/
+    - find ../public/
+  artifacts:
+    paths: ['public']
+    expire_in: 1d
+
+dist:
+  stage: deploy
+  variables:
+    # Force a full clone to make version machinery work.
+    GIT_STRATEGY: clone
+  rules:
+    - if: $CI_COMMIT_TAG
+  script:
+    - bash tools/dist.sh
+  artifacts:
+    paths: ['dist']

.gitmodules

+[submodule "lib/berkeley-db-1.xx"]
+	path = components/micropython/vendor/lib/berkeley-db-1.xx
+	url = https://github.com/pfalcon/berkeley-db-1.xx
+[submodule "lib/micropython-lib"]
+	path = components/micropython/vendor/lib/micropython-lib
+	url = https://github.com/micropython/micropython-lib.git

CHANGELOG.md

+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
+
+## [Unreleased]
+
+## [1.4.0] - 2024-12-24
+### Summary
+
+- documentation reworked and expanded
+- primary context menu: can be opened at any time to view help texts, open the audio mixer or force-exit an application.
+- help viewer: applications can provide context-sensitive help texts to make it easier to figure them out and reduce
+  the load on appilcation writers to explain everything on a small screen.
+- audio mixer: set levels of bl00mbox channels and mute/unmute them. Muted channels don't use CPU.
+- secondary context menu: can be opened in an application menu to delete apps, set them as autostart or mark them as
+  favorite to sort them to the top of menus
+- new preloaded apps: violin, wobbler, mp3 player
+- major rework of captouch driver features
+- added `st3m.ui.widgets` module for easier app integration of user inputs (for example, captouch gestures)
+- bl00mbox can now run channel-specific micropython callbacks whenever the channel is rendered, allowing
+  for much more flexible backgrounded music applications
+
+### Added
+- system: unregistered apps are marked as "new"
+- system: new category "Demos" for things that focus on being technical examples rather than being use case oriented
+- gdb: micropython REPL available while debugging
+- micropython: added `indent` keyword to `json.dumps`/`json.dump`
+- apps: added overrides for OS button
+- apps: added `get_help()` method to provide context sensitive help texts to users
+- settings: Touch UI (default off) activates preview for captouch menu navigation
+- media: support for more (most) mp3 tag types
+- gr33nhouse: sort by application type
+- captouch: no more silent captouch calibration, driver saves persistent calibration file and guides user through manual
+  calibration when none is found.
+- captouch: petals can be turned off run with reduced output to increase data rate
+- captouch: unfiltered data log is accessible
+- captouch: added `PetalLog` helper class for data processing
+- bl00mbox: added .delete() method for various objects, added destructors for better garbabe collection behavior
+- bl00mbox: added RMS volume collection option and provide volume normalization guidelines in flo3r docs
+
+### Changed
+- settings: "Enable WiFi on Boot" option is now "Always-On Wi-Fi" (but is functionally identical), should help reduce confusion about Wi-Fi turning off automatically
+- captouch: normalized positional output in new `.pos`/`.raw_pos` attributes, deprecated old `.position` API
+- captouch: normalized raw capacitance output in new `.raw_cap` attribute, deprecated old `.pressure` API
+- captouch: removed all abstractions that indicate petal pads without replacement,
+  i.e. `InputController.petals[x].ccw` or `InputState.petals[x].raw`
+
+### Fixed
+- updat3r: Improved version comparison logic, making the "you are up to date :)" logic work
+- captouch: petal 5 fully functional
+- bl00mbox: a whole lot of bugs and performance issues (but not all :P)
+
+## [1.3.0] - 2023-11-26
+### Summary
+- Wifi connection UI
+- Media framework
+- SD card works reliably
+- Performance improvements
+- Backend improvements
+- Wider micropython API
+- Improved preloaded applications
+- ...and many bugfixes!
+
+### Added
+- Added the `Audio Passthrough` app for toggling audio passthrough through
+  line-in/mic to speaker or lineout.
+- Added the `w1f1` app for managing wifi access to Settings, incorporates
+  an in-progress cap-touch multi-tap keyboard (`k3yboard`).
+- Added the `Scalar` app in `Music` category for playing scales.
+- Added the `Mandelbrot` app, which illustrates how one can do direct
+  framebuffer access and control 8bpp palettized modes from python.
+- Added configuration of audio adjustments and startup dB level to `settings.json`.
+- Added configuration of wifi credentials + hostname via `settings.json`
+- Added support for apps to set wifi state automatically (configurable in
+  settings: `Let apps change WiFi`)
+- Added task profiler which prints over serial (configurable in
+  settings: `Debug: ftop`)
+- Added an error screen to the `Nick` app when `nick.json` is invalid.
+- Added `urequests` and `uos` support in the simulator.
+- Added audio/video media framework, and `Wurzelitzer` app as a small jukebox
+  frontend - currently supporting mp3 audio, mpeg1 video, GIF and protracker
+  .mod files.
+- Added exporting of built firmwares as part of CI.
+- Added basic implementation of `os.statvfs()` to fetch full/available
+  disk space on flash and SD.
+- Added `set_position` and `scroll_to` methods to `ScrollController`
+- graphics: sprite sheet support for `ctx.image()`
+- graphics: `ctx.parse()` for parsing SVG-path-data/ctx-protocol.
+- graphics: 1,2,4,8,16,24 and 32 bits-per-pixel graphics modes.
+- graphics: direct framebuffer access.
+- graphics: palette setting in 1,2,4 and 8bpp graphics modes.
+- graphics: flags for 2x 3x and 4x pixel doubling, low-latency and direct-ctx modes.
+- graphics: experimental smart redraw mode
+- graphics: clipped and composited overlay buffer
+- graphics: allow a graphics state depth of up to 10 (`ctx.save()` `ctx.restore()`)
+- graphics: virtual framebuffer with scrolling
+- battery: Main menu shows a charge percentage estimate based on real battery characterization
+- Added basic media playback in the `fil3s` app.
+- Added a delete button to `fil3s`/Files app to allow for deleting files,
+  folders and apps on-device.
+- Added new menu categories, `Media` and `Games`, and made category handling more robust
+  to correctly handle introducing new categories in the future.
+- Added configuration UI for audio, appearance and graphics settings.
+- Added configurable LED patterns for the main menu.
+- Added "restore defaults" option in the settings menu.
+- Added wah modulation in `Otamatone`.
+- Added several API functions for `ViewManager` to make complex view handling in apps
+  easier and robust.
+- Added firmware update app, `updat3r`.
+- Added storage information in `About` app.
+- Added audio equalization for built-in speakers.
+- Added a function to retrieve scope data for manual drawing/processing.
+- Added I2C scanner app.
+- Added sensor demo app.
+- Added `CONFIG_DEBUG_GDB_ENABLED` flag for easy debugging over USB JTAG.
+- Added saving/restoring state to several apps.
+- Added variable sequence length support in `gay drums`.
+
+### Changed
+- Changed the st3m\_tar logic to only update files on flash after an update
+  if they've been changed, greatly improving start times after an update.
+- Flashing flow3r through idf.py now automatically restarts it.
+- Switched the REPL/fatal/disk restart button to the OS shoulder button (right
+  shoulder button, unless swapped in settings).
+- Improved performance of the `gr33nhouse` app list by not rendering hidden
+  entries and scrolling ones too long to fit on screen.
+- Changed the audio adjustment logic, and added support for holding down the
+  shoulder to keep increasing/decreasing level.
+- Improved download reliability of the `gr33nhouse` app by adding chunked
+  downloads, some `gc.collect()` calls, progress bar and an error screen.
+- Settings are now automatically loaded and saved when entering and leaving
+  the settings page.
+- Moved the `Clouds` app to the `Badge` menu and updated it to use IMU data.
+- Added a more sane commandline interface to the simulator.
+- More stub functions for the simulator.
+- Improved performance of system menus by not rendering hidden entries.
+- Added visualization of state, instead of an audio scope in UI of `harmonic
+  demo` and `melodic demo`.
+- The system provided scope is now always stroked.
+- Improved BPM tap accuracy in `gay drums`.
+- Some shell code rewritten to avoid the expensive calls `ctx.start_group()` and
+  `ctx.end_group()`.
+- Overlay graphics gets rendered to a separate framebuffer, of which a clipped rectangle
+  is composited during scan-out. The python overlay code has been adapted to keep track
+  of which parts of overlay need refresh.
+- Slightly lower AA quality; for a 3x performance boost in the
+  worst-case scanline rasterization code path.
+- The entry section in `flow3r.toml` can now be omitted if the Application
+  class is called `App`.
+- disabled support for compositing group API in ctx, where used global\_alpha on
+  its own did was responsible for it seeming to work.
+- Split the `settings.py` file into two, creating `settings_menu.py` to hold
+  UI-related code and allow `settings` to be used import loops without
+  in many cases.
+- When running apps through REPL mode (with `mpremote` etc), multi-view apps
+  are now properly handled and don't restart whenever OS shoulder is pressed.
+- A multitude of built-in apps now scroll names to fit the screen.
+- Apps are now sorted and deduplicated by display name, not by folder name.
+- Improved handedness in buttons.
+- `harmonic demo` turned into a fully-featured `chord organ`
+- `menu` key in `flow3r.toml` has been replaced with `category`. The old key can still
+  be used to maintain backwards compatibility with older firmwares.
+- Backported recent improvements for micropython's garbage collection to make it faster.
+- `shoegaze` can now use chords configured in `chord organ`.
+- Changed the priority of additional threads spawned by micropython to be equal to its
+  main thread's priority.
+- Apps that require Wi-Fi connection can directly take the user to Wi-Fi settings.
+- Changed the default app installation directory on flash to `/flash/apps`.
+- `gr33nhouse` now installs apps on SD card if available.
+- Increased the frequency of LED animations.
+- Changed the way LED colors are blended when using slew rates lower than 255 to be
+  more in line with color perception.
+- Rearranged system menu.
+- Made system indicator icons bigger.
+- Removed CCCamp's Wi-Fi settings from the default config.
+- Made InputState and parts of InputController lazily evaluated.
+- bl00mbox: allow circular signal dependencies
+- bl00mbox: several plugins and patches deprecated and replaced with updated
+  versions, see https://gitlab.com/moon2embeddedaudio/bl00mbox/-/blob/main/README.md
+
+### Fixed
+- Fixed `tiny sampler` keeping the microphone active after app exit.
+- Fixed missing `include/` dir on builds on Darwin.
+- Fixed the `time` module in the simulator being broken for apps trying to use it.
+- Fixed wrong petal ordering in the simulator.
+- Fixed simulator not exiting when closed.
+- Fixed `Comic Mono` missing in the simulator.
+- Fixed initialization orientation of display and transform initialization for
+  ctx contexts, (this enables arbitrary transformations to images and gradients.)
+- Fixed broken anti-aliasing for compressed side of curved strokes.
+- Fixed cleanup at exit for firmware apps
+- Fixed sampler start bug in bl00mbox
+- Fixed reset of graphics subsystem upon entering REPL / using mpremote.
+- Fixed multitude of issues with transition animations.
+- Fixed lost captouch and button presses when they're shorter than a think cycle.
+- Fixed `ScrollController`'s handling of high delta values.
+- Fixed many crashes in `fil3s` app.
+- Fixed a crash in `CapScrollController`.
+- Fixed gamma LUT setting for LEDs.
+- Fixed bl00mbox channels leaking on micropython's soft reboot.
+- Fixed importing bl00mbox's fake stub in the simulator.
+- Performance fixes for bl00mbox.
+- Fixed troubles with deleting files on some SD cards (like the bundled one).
+- Fixed the default I2C1 pins in micropython's I2C interface.
+- Fixed large files being truncated when installing apps via `gr33nhouse`.
+- Fixed LED color handling in the simulator.
+- Fixed flickering .down property of Pressable when going through REPEATED state.
+
+
+## [1.2.0] - 2023-08-18
+### Added
+- Added a WiFi status indicator icon.
+- Added a battery status indicator icon.
+- Added support for loading apps from `/sd/apps` and `/flash/apps`.
+- Added an error screen when apps fail to start.
+- Added Python/st3m API to access battery charge status.
+- Added the ability to always hide icons (*System* ➜ *Settings* ➜ *Show Icons*).
+
+### Fixed
+- File descriptor leak on app load.  This would lead to the OS crashing when
+  too many apps are installed.
+
+
+## [1.1.1] - 2023-08-17
+### Fixed
+- Crash on WiFi startup
+
+
+## [1.1.0] - 2023-08-17
+
+### Added
+- Added _Comic Mono_ font.
+- Added a setting for automatically connecting to Camp WiFi.
+- Added a *System* ➜ *Get Apps* App for downloading apps directly from <https://flow3r.garden/apps/>.
+- Added `ApplicationContext.bundle_path` so apps can find out what directory
+  they live in.  This should be used for loading app assets from the correct
+  path.
+- Added TLS support for MicroPython.
+- Added modules for `.tar.gz` extraction.
+- Added `aioble` module (Bluetooth Low Energy).
+- Added line-in support to bl00mbox.
+- Added pronoun support in the Nick app.
+- Added color options in the Nick app.
+- Added IMU-based rotation in the Nick app.
+
+### Changed
+- `ctx.get_font_name()` now raises an exception for unknown fonts.
+- Raised max concurrent texture limit to 32.
+
+### Fixed
+- Fixed PNG without alpha and JPEG support by enabling `CTX_FORMAT_RGB8`.
+- Fixed image cache eviction by introducing a ctx frameclock.
+- Fixed incorrect merging of settings dicts in `st3m.settings`.
+- Fixed some USB problems.
+- Fixed sound filenames not working when they start with `/flash/` or `/sd/`.
+- Fixed syntax errors in `flow3r.toml` crashing the menu.
+
+
+## [1.0.0] - 2023-08-13
+
+Initial Release
+
+
+[unreleased]: https://git.flow3r.garden/flow3r/flow3r-firmware/-/compare/v1.4.0...main
+[1.4.0]: https://git.flow3r.garden/flow3r/flow3r-firmware/-/compare/v1.3.0...v1.4.0
+[1.3.0]: https://git.flow3r.garden/flow3r/flow3r-firmware/-/compare/v1.2.0...v1.3.0
+[1.2.0]: https://git.flow3r.garden/flow3r/flow3r-firmware/-/compare/v1.1.1...v1.2.0
+[1.1.1]: https://git.flow3r.garden/flow3r/flow3r-firmware/-/compare/v1.1.0...v1.1.1
+[1.1.0]: https://git.flow3r.garden/flow3r/flow3r-firmware/-/compare/v1.0.0...v1.1.0
+[1.0.0]: https://git.flow3r.garden/flow3r/flow3r-firmware/-/tags/v1.0.0
+

CMakeLists.txt

+cmake_minimum_required(VERSION 3.12)
+
+set(IDF_TARGET esp32s3)
+
+include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+
+project(flow3r)
+
+# Make `1.1` literals into single-point precision float instead of double
+# precision. Also warn any time something gets promoted to a double. We
+# generally don't want doubles, doubles on ESP32 bad.
+idf_component_get_property(st3m_lib st3m COMPONENT_LIB)
+idf_component_get_property(flow3r_bsp_lib flow3r_bsp COMPONENT_LIB)
+idf_component_get_property(bl00mbox_lib bl00mbox COMPONENT_LIB)
+if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
+    target_compile_options(${st3m_lib} PRIVATE -cl-single-precision-constant -Wdouble-promotion)
+    target_compile_options(${flow3r_bsp_lib} PRIVATE -cl-single-precision-constant -Wdouble-promotion)
+    target_compile_options(${bl00mbox_lib} PRIVATE -Wno-error=unknown-pragmas)
+else()
+    target_compile_options(${st3m_lib} PRIVATE -fsingle-precision-constant -Wdouble-promotion)
+    target_compile_options(${flow3r_bsp_lib} PRIVATE -fsingle-precision-constant -Wdouble-promotion)
+endif()

COPYING.LESSER

+                   GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+
+  This version of the GNU Lesser General Public License incorporates
+the terms and conditions of version 3 of the GNU General Public
+License, supplemented by the additional permissions listed below.
+
+  0. Additional Definitions.
+
+  As used herein, "this License" refers to version 3 of the GNU Lesser
+General Public License, and the "GNU GPL" refers to version 3 of the GNU
+General Public License.
+
+  "The Library" refers to a covered work governed by this License,
+other than an Application or a Combined Work as defined below.
+
+  An "Application" is any work that makes use of an interface provided
+by the Library, but which is not otherwise based on the Library.
+Defining a subclass of a class defined by the Library is deemed a mode
+of using an interface provided by the Library.
+
+  A "Combined Work" is a work produced by combining or linking an
+Application with the Library.  The particular version of the Library
+with which the Combined Work was made is also called the "Linked
+Version".
+
+  The "Minimal Corresponding Source" for a Combined Work means the
+Corresponding Source for the Combined Work, excluding any source code
+for portions of the Combined Work that, considered in isolation, are
+based on the Application, and not on the Linked Version.
+
+  The "Corresponding Application Code" for a Combined Work means the
+object code and/or source code for the Application, including any data
+and utility programs needed for reproducing the Combined Work from the
+Application, but excluding the System Libraries of the Combined Work.
+
+  1. Exception to Section 3 of the GNU GPL.
+
+  You may convey a covered work under sections 3 and 4 of this License
+without being bound by section 3 of the GNU GPL.
+
+  2. Conveying Modified Versions.
+
+  If you modify a copy of the Library, and, in your modifications, a
+facility refers to a function or data to be supplied by an Application
+that uses the facility (other than as an argument passed when the
+facility is invoked), then you may convey a copy of the modified
+version:
+
+   a) under this License, provided that you make a good faith effort to
+   ensure that, in the event an Application does not supply the
+   function or data, the facility still operates, and performs
+   whatever part of its purpose remains meaningful, or
+
+   b) under the GNU GPL, with none of the additional permissions of
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+
+  3. Object Code Incorporating Material from Library Header Files.
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+(ten or fewer lines in length), you do both of the following:
+
+   a) Give prominent notice with each copy of the object code that the
+   Library is used in it and that the Library and its use are
+   covered by this License.
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+  4. Combined Works.
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+the following:
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+   the Library is used in it and that the Library and its use are
+   covered by this License.
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+   document.
+
+   c) For a Combined Work that displays copyright notices during
+   execution, include the copyright notice for the Library among
+   these notices, as well as a reference directing the user to the
+   copies of the GNU GPL and this license document.
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+   d) Do one of the following:
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+       the Linked Version to produce a modified Combined Work, in the
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+
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+   you use option 4d0, the Installation Information must accompany
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+   for conveying Corresponding Source.)
+
+  5. Combined Libraries.
+
+  You may place library facilities that are a work based on the
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+facilities that are not Applications and are not covered by this
+License, and convey such a combined library under terms of your
+choice, if you do both of the following:
+
+   a) Accompany the combined library with a copy of the same work based
+   on the Library, uncombined with any other library facilities,
+   conveyed under the terms of this License.
+
+   b) Give prominent notice with the combined library that part of it
+   is a work based on the Library, and explaining where to find the
+   accompanying uncombined form of the same work.
+
+  6. Revised Versions of the GNU Lesser General Public License.
+
+  The Free Software Foundation may publish revised and/or new versions
+of the GNU Lesser General Public License from time to time. Such new
+versions will be similar in spirit to the present version, but may
+differ in detail to address new problems or concerns.
+
+  Each version is given a distinguishing version number. If the
+Library as you received it specifies that a certain numbered version
+of the GNU Lesser General Public License "or any later version"
+applies to it, you have the option of following the terms and
+conditions either of that published version or of any later version
+published by the Free Software Foundation. If the Library as you
+received it does not specify a version number of the GNU Lesser
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+
+  If the Library as you received it specifies that a proxy can decide
+whether future versions of the GNU Lesser General Public License shall
+apply, that proxy's public statement of acceptance of any version is
+permanent authorization for you to choose that version for the
+Library.

README.md

+# flow3r badge
+
+See https://docs.flow3r.garden/badge/firmware-development.html for a firmware development guide.
+
+## License
+All original source code in this repository is Copyright (C) 2023 Flow3r Badge Contributors. This source code is licensed under the GNU Lesser General Public License Version 3.0 as described in the file COPYING.
+
+This program is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License Version 3.0 as published by the Free Software Foundation.
+
+This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License Version 3.0 along with this program.  If not, see <https://www.gnu.org/licenses/>.

components/audio_mod/CMakeLists.txt

+idf_component_register(
+    SRCS
+        audio_mod.c
+    INCLUDE_DIRS
+        .
+        ../ctx
+        ../st3m
+)

components/audio_mod/audio_mod.c

+#ifndef __clang__
+#pragma GCC optimize("O2")
+#endif
+
+#include <fcntl.h>
+#include <st3m_audio.h>
+#include <st3m_media.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "ctx.h"
+
+#define POCKETMOD_IMPLEMENTATION
+#include "pocketmod.h"
+
+typedef struct {
+    st3m_media control;
+    pocketmod_context pocketmod;
+    uint8_t *data;
+    size_t size;
+    char *path;
+    float scroll_pos;
+} mod_state;
+
+static void mod_draw(st3m_media *media, Ctx *ctx) {
+    mod_state *self = (void *)media;
+
+    ctx_rectangle(ctx, -120, -120, 240, 240);
+    ctx_gray(ctx, 0);
+    ctx_fill(ctx);
+    // ctx_arc(ctx, 0, 0, 10, 10);
+    ctx_rgb(ctx, 1.0, 1.0, 1.0);
+    ctx_font_size(ctx, 20);
+    char buf[100];
+    sprintf(buf, "pat:%i/%i line:%i", self->pocketmod.pattern,
+            self->pocketmod.num_patterns, self->pocketmod.line);
+    ctx_text_align(ctx, CTX_TEXT_ALIGN_CENTER);
+    ctx_move_to(ctx, 0, -20);
+    ctx_text(ctx, buf);
+    ctx_fill(ctx);
+
+    ctx_font_size(ctx, 14);
+    int xpos = 0;
+    int str_width = ctx_text_width(ctx, self->path);
+    if (str_width > 220) {
+        xpos = ctx_sinf(self->scroll_pos) * (str_width - 220) / 2;
+    }
+    ctx_move_to(ctx, xpos, 14);
+    ctx_gray(ctx, 0.6);
+    ctx_text(ctx, self->path);
+}
+
+static void mod_think(st3m_media *media, float ms_elapsed) {
+    mod_state *self = (void *)media;
+    if (self->control.paused) return;
+
+    if (self->control.seek == 0) {
+        pocketmod_init(&self->pocketmod, self->data, self->size, 48000);
+        self->control.seek = -1;
+    }
+
+    int samples_needed = (ms_elapsed / 1000.0) * 48000;
+    if (samples_needed > 1000) samples_needed = 1000;
+
+    float rendered[samples_needed * 2];
+    int rend = pocketmod_render(&self->pocketmod, rendered, sizeof(rendered));
+    st3m_pcm_queue_float(48000, 2, rend / (sizeof(float) * 2), rendered);
+
+    if (self->control.duration == 0) {
+        self->control.duration = self->pocketmod.num_patterns + 1;
+    }
+    if (self->pocketmod.pattern >= self->control.duration)
+        self->control.duration = self->pocketmod.pattern + 1;
+    self->control.position = self->pocketmod.pattern;
+    if (self->pocketmod.loop_count)
+        self->control.duration = self->control.position;
+
+    self->scroll_pos += ms_elapsed / 1000.0;
+}
+
+static void mod_destroy(st3m_media *media) {
+    mod_state *self = (void *)media;
+    if (self->data) free(self->data);
+    if (self->path) free(self->path);
+    free(self);
+}
+
+static int file_get_contents(const char *path, uint8_t **contents,
+                             size_t *length) {
+    FILE *file;
+    long size;
+    long remaining;
+    uint8_t *buffer;
+    file = fopen(path, "rb");
+    if (!file) {
+        return -1;
+    }
+    fseek(file, 0, SEEK_END);
+    size = remaining = ftell(file);
+
+    if (length) {
+        *length = size;
+    }
+    rewind(file);
+    buffer = malloc(size + 2);
+    if (!buffer) {
+        fclose(file);
+        return -1;
+    }
+    remaining -= fread(buffer, 1, remaining, file);
+    if (remaining) {
+        fclose(file);
+        free(buffer);
+        return -1;
+    }
+    fclose(file);
+    *contents = (unsigned char *)buffer;
+    buffer[size] = 0;
+    return 0;
+}
+
+st3m_media *st3m_media_load_mod(const char *path) {
+    mod_state *self = (mod_state *)malloc(sizeof(mod_state));
+    memset(self, 0, sizeof(mod_state));
+    self->control.draw = mod_draw;
+    self->control.think = mod_think;
+    self->control.destroy = mod_destroy;
+    self->control.has_audio = true;
+    file_get_contents(path, &self->data, &self->size);
+    if (!self->data ||
+        !pocketmod_init(&self->pocketmod, self->data, self->size, 48000)) {
+        if (self->data) free(self->data);
+        free(self);
+        return NULL;
+    }
+    self->path = strdup(path);
+    self->scroll_pos = 0;
+    return (st3m_media *)self;
+}

components/audio_mp3/CMakeLists.txt

+idf_component_register(
+    SRCS
+        audio_mp3.c
+    INCLUDE_DIRS
+        .
+        ../ctx
+        ../st3m
+)

components/audio_mp3/LICENSE

+CC0 1.0 Universal
+
+Statement of Purpose
+
+The laws of most jurisdictions throughout the world automatically confer
+exclusive Copyright and Related Rights (defined below) upon the creator and
+subsequent owner(s) (each and all, an "owner") of an original work of
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+
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+works ("Commons") that the public can reliably and without fear of later
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+and redistribute as freely as possible in any form whatsoever and for any
+purposes, including without limitation commercial purposes. These owners may
+contribute to the Commons to promote the ideal of a free culture and the
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+efforts of others.
+
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+of additional consideration or compensation, the person associating CC0 with a
+Work (the "Affirmer"), to the extent that he or she is an owner of Copyright
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+Copyright and Related Rights in the Work and the meaning and intended legal
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+
+1. Copyright and Related Rights. A Work made available under CC0 may be
+protected by copyright and related or neighboring rights ("Copyright and
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+to, the following:
+
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+
+  ii. moral rights retained by the original author(s) and/or performer(s);
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+  including any amended or successor version of such directive); and
+
+  vii. other similar, equivalent or corresponding rights throughout the world
+  based on applicable law or treaty, and any national implementations thereof.
+
+2. Waiver. To the greatest extent permitted by, but not in contravention of,
+applicable law, Affirmer hereby overtly, fully, permanently, irrevocably and
+unconditionally waives, abandons, and surrenders all of Affirmer's Copyright
+and Related Rights and associated claims and causes of action, whether now
+known or unknown (including existing as well as future claims and causes of
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+the Waiver for the benefit of each member of the public at large and to the
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+shall not be subject to revocation, rescission, cancellation, termination, or
+any other legal or equitable action to disrupt the quiet enjoyment of the Work
+by the public as contemplated by Affirmer's express Statement of Purpose.
+
+3. Public License Fallback. Should any part of the Waiver for any reason be
+judged legally invalid or ineffective under applicable law, then the Waiver
+shall be preserved to the maximum extent permitted taking into account
+Affirmer's express Statement of Purpose. In addition, to the extent the Waiver
+is so judged Affirmer hereby grants to each affected person a royalty-free,
+non transferable, non sublicensable, non exclusive, irrevocable and
+unconditional license to exercise Affirmer's Copyright and Related Rights in
+the Work (i) in all territories worldwide, (ii) for the maximum duration
+provided by applicable law or treaty (including future time extensions), (iii)
+in any current or future medium and for any number of copies, and (iv) for any
+purpose whatsoever, including without limitation commercial, advertising or
+promotional purposes (the "License"). The License shall be deemed effective as
+of the date CC0 was applied by Affirmer to the Work. Should any part of the
+License for any reason be judged legally invalid or ineffective under
+applicable law, such partial invalidity or ineffectiveness shall not
+invalidate the remainder of the License, and in such case Affirmer hereby
+affirms that he or she will not (i) exercise any of his or her remaining
+Copyright and Related Rights in the Work or (ii) assert any associated claims
+and causes of action with respect to the Work, in either case contrary to
+Affirmer's express Statement of Purpose.
+
+4. Limitations and Disclaimers.
+
+  a. No trademark or patent rights held by Affirmer are waived, abandoned,
+  surrendered, licensed or otherwise affected by this document.
+
+  b. Affirmer offers the Work as-is and makes no representations or warranties
+  of any kind concerning the Work, express, implied, statutory or otherwise,
+  including without limitation warranties of title, merchantability, fitness
+  for a particular purpose, non infringement, or the absence of latent or
+  other defects, accuracy, or the present or absence of errors, whether or not
+  discoverable, all to the greatest extent permissible under applicable law.
+
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+  that may apply to the Work or any use thereof, including without limitation
+  any person's Copyright and Related Rights in the Work. Further, Affirmer
+  disclaims responsibility for obtaining any necessary consents, permissions
+  or other rights required for any use of the Work.
+
+  d. Affirmer understands and acknowledges that Creative Commons is not a
+  party to this document and has no duty or obligation with respect to this
+  CC0 or use of the Work.
+
+For more information, please see
+<http://creativecommons.org/publicdomain/zero/1.0/>
+

components/audio_mp3/audio_mp3.c

+#ifndef __clang__
+#pragma GCC optimize("O2")
+#endif
+
+#include <fcntl.h>
+#include <st3m_audio.h>
+#include <st3m_media.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "lwip/igmp.h"
+#include "lwip/ip4.h"
+#include "lwip/netdb.h"
+#include "lwip/sockets.h"
+
+#include "ctx.h"
+
+#define MINIMP3_NONSTANDARD_BUT_LOGICAL
+#define MINIMP3_NO_SIMD
+#define MINIMP3_IMPLEMENTATION
+#include "minimp3.h"
+
+typedef struct {
+    st3m_media control;
+    mp3dec_t mp3d;
+    char *path;
+    char *artist;
+    char *title;
+    int year;
+    int started;
+    int samplerate;
+    int channels;
+    uint8_t *data;
+    size_t size;
+    size_t count;
+
+    int pos;
+    int offset;
+    int buffer_size;
+
+    int file_size;
+    FILE *file;
+
+    int socket;
+
+    int in_buffering;
+    float scroll_pos;
+} mp3_state;
+
+static int has_data(mp3_state *mp3) {
+    if (mp3->file) return 1;
+    fd_set rfds;
+    struct timeval tv = { 0, 0 };
+    FD_ZERO(&rfds);
+    FD_SET(mp3->socket, &rfds);
+    if (select(mp3->socket + 1, &rfds, NULL, NULL, &tv) == 1)
+        return FD_ISSET(mp3->socket, &rfds);
+    return 0;
+}
+
+static void mp3_fetch_data(mp3_state *mp3) {
+    if (mp3->pos) {
+        memmove(mp3->data, &mp3->data[mp3->pos], mp3->count - mp3->pos);
+        mp3->offset += mp3->pos;
+        mp3->count -= mp3->pos;
+        mp3->pos = 0;
+    }
+
+    // if incoming data-buffer falls below 16kb - do a full buffer fill
+    if (!mp3->file && (mp3->count < 16 * 1024)) {
+        mp3->in_buffering = 1;
+    }
+
+    if ((mp3->size - mp3->count > 0) && has_data(mp3)) {
+        int desire_bytes = (mp3->size - mp3->count);
+        if (desire_bytes > 2048) desire_bytes = 2048;
+        if (desire_bytes) {
+            int read_bytes;
+            if (mp3->file)
+                read_bytes =
+                    fread(mp3->data + mp3->count, 1, desire_bytes, mp3->file);
+            else
+                read_bytes =
+                    read(mp3->socket, mp3->data + mp3->count, desire_bytes);
+            mp3->count += read_bytes;
+        }
+    }
+}
+
+static char *mp3_get_string(st3m_media *media, const char *key) {
+    mp3_state *self = (void *)media;
+    if (strcmp(key, "artist") == 0) {
+        return strdup(self->artist);
+    } else if (strcmp(key, "title") == 0) {
+        return strdup(self->title);
+    }
+    return NULL;
+}
+
+static void mp3_draw(st3m_media *media, Ctx *ctx) {
+    mp3_state *self = (void *)media;
+
+    ctx_rectangle(ctx, -120, -120, 240, 240);
+    ctx_gray(ctx, 0);
+    ctx_fill(ctx);
+    ctx_rgb(ctx, 1.0, 1.0, 1.0);
+    ctx_rectangle(ctx, -120, 0, 240, 1);
+    ctx_rectangle(ctx, -120 + self->offset * 240.0 / self->file_size, -32, 2,
+                  64);
+    ctx_fill(ctx);
+    ctx_font_size(ctx, 24);
+    ctx_text_align(ctx, CTX_TEXT_ALIGN_CENTER);
+
+    int xpos = 0;
+    int str_width = ctx_text_width(ctx, self->artist);
+    if (str_width > 200) {
+        xpos = ctx_sinf(self->scroll_pos) * (str_width - 200) / 2;
+    }
+    ctx_move_to(ctx, xpos, -40);
+    ctx_text(ctx, self->artist);
+
+    str_width = ctx_text_width(ctx, self->title);
+    xpos = 0;
+    if (str_width > 200) {
+        xpos = ctx_sinf(self->scroll_pos) * (str_width - 200) / 2;
+    }
+    ctx_move_to(ctx, xpos, 64);
+    ctx_text(ctx, self->title);
+
+    ctx_font_size(ctx, 14);
+    str_width = ctx_text_width(ctx, self->path);
+    xpos = 0;
+    if (str_width > 220) {
+        xpos = ctx_sinf(self->scroll_pos) * (str_width - 220) / 2;
+    }
+    ctx_move_to(ctx, xpos, 14);
+    ctx_gray(ctx, 0.6);
+    ctx_text(ctx, self->path);
+
+    if (!self->file) {
+        ctx_rectangle(ctx, -100, 65, self->count * 200.0 / self->size, 55);
+        if (self->in_buffering)
+            ctx_rgba(ctx, 0.8, 0.2, 0.0, 1.0);
+        else
+            ctx_gray(ctx, 0.2);
+        ctx_fill(ctx);
+    }
+}
+
+static void mp3_think(st3m_media *media, float ms_elapsed) {
+    mp3_state *self = (void *)media;
+
+    if (self->file && self->control.seek >= 0) {
+        if (self->control.seek > 1.0) {
+            self->control.seek = 1.0;
+        }
+        float seek = self->control.seek * self->control.duration;
+        fseek(self->file, seek, SEEK_SET);
+        self->offset = seek;
+        self->pos = 0;
+        self->count = 0;
+        self->control.time = 0;
+        self->control.position = self->offset;
+        self->control.seek = -1;
+        mp3dec_init(&self->mp3d);
+    }
+
+    mp3_fetch_data(self);
+
+    self->scroll_pos += ms_elapsed / 1000.0;
+
+    if (self->in_buffering) {
+        if (self->size - self->count > 0) return;
+        self->in_buffering = 0;
+    }
+
+    if (self->control.paused) return;
+
+    if (self->file) {
+        self->control.position = self->offset;
+        if (self->offset + 512 >= self->file_size)
+            self->control.position = self->file_size;
+    }
+
+    if (!self->started) {
+        self->started = 1;
+        mp3_think(media, 100);
+    }
+    int samples_needed = (((st3m_pcm_queue_length() - st3m_pcm_queued()) / 2)) /
+                         48000.0 * self->samplerate;
+
+    int samples;
+    mp3dec_frame_info_t info = {
+        0,
+    };
+    if (samples_needed > 0 &&
+        ((self->offset + 512 < self->file_size) || (!self->file))) {
+        do {
+            int16_t rendered[MINIMP3_MAX_SAMPLES_PER_FRAME];
+            samples =
+                mp3dec_decode_frame(&self->mp3d, self->data + self->pos,
+                                    self->count - self->pos, rendered, &info);
+            self->pos += info.frame_bytes;
+            if (samples) {
+                self->samplerate = info.hz;
+                self->channels = info.channels;
+                self->control.time += samples / (float)self->samplerate;
+                st3m_pcm_queue_s16(self->samplerate, self->channels, samples,
+                                   rendered);
+            } else if (info.frame_bytes) {
+                mp3_fetch_data(self);
+            } else {
+                break;
+            }
+            samples_needed -= (samples);
+        } while (samples_needed > 0);
+    }
+}
+
+static void mp3_destroy(st3m_media *media) {
+    mp3_state *self = (void *)media;
+    if (self->data) free(self->data);
+    if (self->file) fclose(self->file);
+    if (self->socket) {
+        shutdown(self->socket, SHUT_RDWR);
+        close(self->socket);
+    }
+    if (self->path) free(self->path);
+    if (self->title) free(self->title);
+    if (self->artist) free(self->artist);
+    free(self);
+}
+
+typedef struct {
+    char tag[3];
+    char title[30];
+    char artist[30];
+    char album[30];
+    char year[4];
+    char comment[30];
+    char genre[1];
+    char pad[128];
+} id3tag_t;
+
+st3m_media *st3m_media_load_mp3(const char *path) {
+    mp3_state *self = (mp3_state *)malloc(sizeof(mp3_state));
+    if (!self) return NULL;
+    memset(self, 0, sizeof(mp3_state));
+    self->control.draw = mp3_draw;
+    self->control.think = mp3_think;
+    self->control.destroy = mp3_destroy;
+    self->control.get_string = mp3_get_string;
+    self->control.has_audio = true;
+    self->samplerate = 44100;
+    self->buffer_size = 32 * 1024;
+    self->scroll_pos = 0;
+
+    if (!strncmp(path, "http://", 7)) {
+        int port = 80;
+        char *hostname = strdup(path + 7);
+        char *rest = NULL;
+        self->buffer_size = 96 * 1024;
+        rest = strchr(hostname, '/') + 1;
+        strchr(hostname, '/')[0] = 0;
+        if (strchr(hostname, ':')) {
+            port = atoi(strchr(hostname, ':') + 1);
+            strchr(hostname, ':')[0] = 0;
+        }
+
+        struct hostent *host;
+        struct sockaddr_in addr;
+        self->socket = socket(PF_INET, SOCK_STREAM, 0);
+        if (self->socket < 0) {
+            free(hostname);
+            mp3_destroy((st3m_media *)self);
+            return NULL;
+        }
+        int flag = 1;
+        setsockopt(self->socket, IPPROTO_TCP, TCP_NODELAY, &flag, sizeof(int));
+        memset(&addr, 0, sizeof(addr));
+        addr.sin_family = AF_INET;
+        addr.sin_port = htons(port);
+        host = gethostbyname(hostname);
+        if (!host) {
+            mp3_destroy((st3m_media *)self);
+            free(hostname);
+            return NULL;
+        }
+        addr.sin_addr.s_addr = ((long unsigned int **)host->h_addr_list)[0][0];
+
+        if (connect(self->socket, (struct sockaddr *)&addr, sizeof(addr)) ==
+            0) {
+            char s[1024];
+            sprintf(s, "GET /%s HTTP/1.1\r\n", rest);
+            write(self->socket, s, strlen(s));
+            sprintf(s, "Range: bytes=0-\r\n");
+            write(self->socket, s, strlen(s));
+            if (hostname) {
+                sprintf(s, "Host: %s\r\n", hostname);
+                write(self->socket, s, strlen(s));
+            }
+            sprintf(s, "User-Agent: flow3r\r\n");
+            write(self->socket, s, strlen(s));
+            sprintf(s, "\r\n");
+            write(self->socket, s, strlen(s));
+            fsync(self->socket);
+
+            self->data = malloc(self->buffer_size);
+            self->size = self->buffer_size;
+
+            mp3dec_init(&self->mp3d);
+            self->control.duration = -1;
+            free(hostname);
+
+            if (!self->data) {
+                mp3_destroy((st3m_media *)self);
+                return NULL;
+            }
+
+            self->in_buffering = 1;
+            self->path = strdup(path);
+            return (st3m_media *)self;
+        }
+        free(hostname);
+
+        mp3_destroy((st3m_media *)self);
+        return NULL;
+    }
+    st3m_media_tags_t *tags = st3m_media_get_tags(path);
+    if (tags) {
+        if (tags->title) self->title = strdup(tags->title);
+        if (tags->artist) self->artist = strdup(tags->artist);
+        self->year = tags->year;
+        st3m_media_free_tags(tags);
+    }
+
+    self->file = fopen(path, "r");
+    if (!self->file) {
+        mp3_destroy((st3m_media *)self);
+        return NULL;
+    }
+    fseek(self->file, 0, SEEK_END);
+    self->file_size = ftell(self->file);
+
+    self->data = malloc(self->buffer_size);
+    if (!self->data) {
+        mp3_destroy((st3m_media *)self);
+        return NULL;
+    }
+    self->size = self->buffer_size;
+    mp3dec_init(&self->mp3d);
+    self->control.duration = self->file_size;
+
+    self->path = strdup(path);
+    if (!self->path) {
+        mp3_destroy((st3m_media *)self);
+        return NULL;
+    }
+
+    rewind(self->file);
+
+    return (st3m_media *)self;
+}
+
+static uint32_t id3v2_decode_size(char *start, bool syncsafe) {
+    uint32_t ret = 0;
+    if (syncsafe) {
+        for (int j = 0; j < 4; j++) {
+            ret += (start[3 - j] & 0b1111111) << (7 * j);
+        }
+    } else {
+        for (int j = 0; j < 4; j++) {
+            ret += start[3 - j] << (8 * j);
+        }
+    }
+    return ret;
+}
+
+static char *strndup_textframe(char *content, int len) {
+    char *ret;
+    if (content[0] == 1) {  // corrupt bytes should be assumed to be 0
+        // utf-16:
+        int string_start = 1;
+        bool byte_flip = false;
+        if (content[1] == ((char)0xFF) && content[2] == ((char)0xFE)) {
+            string_start += 2;
+        } else if (content[1] == ((char)0xFE) && content[2] == ((char)0xFF)) {
+            string_start += 2;
+            byte_flip = true;
+        }
+        int ascii_len =
+            (len - string_start) /
+            2;  // one extra byte is in there already, preventing round-downs
+        ret = malloc(ascii_len + 1);
+        if (!ret) return NULL;
+        ret[ascii_len] = 0;
+        for (int i = 0; i < ascii_len; i++) {
+            if (content[string_start + 2 * i + 1 - byte_flip]) {
+                ret[i] = '?';
+            } else {
+                ret[i] = content[string_start + 2 * i + byte_flip];
+            }
+        }
+    } else {
+        // iso-8859-1
+        ret = strndup(&content[1], len - 1);
+    }
+    int ret_len = strlen(ret);
+    // filter out high bit special chars
+    for (int i = 0; i < ret_len; i++) {
+        if (ret[i] & 0x80) ret[i] = '?';
+    }
+    return ret;
+}
+
+enum supported_tags { NONE, TITLE, ARTIST, ALBUM, TRACK_NUMBER, YEAR };
+
+st3m_media_tags_t *audio_mp3_get_tags(const char *path) {
+    // returns a new media_tags_t object with tag information
+    // retrieved from file at path (or NULL). freeing is up to the user.
+    FILE *file = fopen(path, "r");
+    if (!file) return NULL;
+    fseek(file, 0, SEEK_END);
+    int file_size = ftell(file);
+
+    st3m_media_tags_t *tags = calloc(1, sizeof(st3m_media_tags_t));
+    if (!tags) return NULL;
+
+    // ID3v1/ID3v1.1
+    fseek(file, file_size - 128, SEEK_SET);
+    id3tag_t id3;
+    fread(&id3, 128, 1, file);
+    if (id3.tag[0] == 'T' && id3.tag[1] == 'A' && id3.tag[2] == 'G') {
+        tags->title = strndup(id3.title, 30);
+        while (tags->title[strlen(tags->title) - 1] == ' ')
+            tags->title[strlen(tags->title) - 1] = 0;
+
+        tags->artist = strndup(id3.artist, 30);
+        while (tags->artist[strlen(tags->artist) - 1] == ' ')
+            tags->artist[strlen(tags->artist) - 1] = 0;
+
+        tags->album = strndup(id3.album, 30);
+        while (tags->album[strlen(tags->album) - 1] == ' ')
+            tags->album[strlen(tags->album) - 1] = 0;
+
+        tags->year = atoi(id3.year);
+
+        if (!id3.comment[28]) {
+            tags->track_number = id3.comment[29];
+        }
+        fclose(file);
+        return tags;
+    }
+
+    // ID3v2
+    fseek(file, 0, SEEK_SET);
+    char buf[10];
+    fread(buf, 10, 1, file);
+    if (buf[0] == 'I' && buf[1] == 'D' && buf[2] == '3') {
+        uint32_t frame_pos = 10;
+        uint8_t version = buf[3];
+        if (version < 2 || version > 4) {
+            fclose(file);
+            free(tags);
+            return NULL;
+        }
+        uint32_t tag_size = 10 + id3v2_decode_size(&buf[6], version >= 3);
+        if (buf[4] & 0b100000) {  // extended header
+            fread(buf, 10, 1, file);
+            frame_pos += id3v2_decode_size(&buf[0], version >= 3);
+        }
+        while (frame_pos < tag_size) {
+            uint32_t frame_size = 0;
+            fseek(file, frame_pos, SEEK_SET);
+            if (version > 2) {
+                fread(buf, 10, 1, file);
+                frame_size = id3v2_decode_size(&buf[4], version >= 4);
+                frame_pos += 10;
+            } else {
+                fread(buf, 6, 1, file);
+                frame_size = id3v2_decode_size(&buf[3], false);
+                frame_size >>= 8;
+                frame_pos += 6;
+            }
+#if 0
+            printf("\nframe pos: %lu, frame size: %lu, tag size: %lu\n", frame_pos, frame_size, tag_size);
+            char tag[5];
+            memcpy(tag, buf, 4);
+            tag[4] = 0;
+            printf("tag: %s\n", tag);
+#endif
+
+            if (frame_pos + frame_size > tag_size) break;
+
+            enum supported_tags frame_tag = NONE;
+            if (version > 2) {
+                if (strncmp(buf, "TIT2", 4) == 0) {
+                    frame_tag = TITLE;
+                } else if (strncmp(buf, "TPE1", 4) == 0) {
+                    frame_tag = ARTIST;
+                } else if (strncmp(buf, "TRCK", 4) == 0) {
+                    frame_tag = TRACK_NUMBER;
+                } else if (strncmp(buf, "TYER", 4) == 0) {
+                    frame_tag = YEAR;
+                } else if (strncmp(buf, "TALB", 4) == 0) {
+                    frame_tag = ALBUM;
+                }
+            } else {
+                if (strncmp(buf, "TT2", 3) == 0) {
+                    frame_tag = TITLE;
+                } else if (strncmp(buf, "TP1", 3) == 0) {
+                    frame_tag = ARTIST;
+                } else if (strncmp(buf, "TRK", 3) == 0) {
+                    frame_tag = TRACK_NUMBER;
+                } else if (strncmp(buf, "TYE", 3) == 0) {
+                    frame_tag = YEAR;
+                } else if (strncmp(buf, "TAL", 3) == 0) {
+                    frame_tag = ALBUM;
+                }
+            }
+            if (frame_tag == NONE) continue;
+
+            char *fbuf = malloc(
+                frame_size);  // putting it on heap bc task stack may overflow
+            if (!fbuf)
+                continue;  // earlier, don't wanna worried about limits here
+            if (fread(fbuf, 1, frame_size, file) != frame_size) {
+                free(fbuf);
+                break;
+            }
+
+            switch (frame_tag) {
+                case TITLE:
+                    tags->title = strndup_textframe(fbuf, frame_size);
+                    break;
+                case ARTIST:
+                    tags->artist = strndup_textframe(fbuf, frame_size);
+                    break;
+                case TRACK_NUMBER:;
+                    char *slashpos = strchr(fbuf, '/');
+                    if (slashpos) *slashpos = 0;
+                    tags->track_number = atoi(fbuf);
+                    break;
+                case YEAR:
+                    tags->year = atoi(fbuf);
+                    break;
+                case ALBUM:
+                    tags->album = strndup_textframe(fbuf, frame_size);
+                    break;
+                default:
+                    break;  // should never be reached, just to make compiler
+                            // happy
+            }
+            free(fbuf);
+            if (tags->title && tags->artist && tags->track_number &&
+                tags->year && tags->album)
+                break;
+            frame_pos += frame_size;
+        }
+        fclose(file);
+        return tags;
+    }
+
+    free(tags);
+    fclose(file);
+    return NULL;
+}

components/bl00mbox/.clang-tidy

+Checks: '-*,clang-analyzer-osx.SecKeychainAPI'

components/bl00mbox/CMakeLists.txt

+#SPDX-License-Identifier: CC0-1.0
+
+idf_component_register(
+    SRCS
+        bl00mbox.c
+        bl00mbox_audio.c
+        bl00mbox_user.c
+        bl00mbox_os.c
+        bl00mbox_plugin_registry.c
+        bl00mbox_radspa_requirements.c
+        bl00mbox_containers.c
+        radspa/standard_plugin_lib/osc.c
+        radspa/standard_plugin_lib/osc_fm.c
+        radspa/standard_plugin_lib/env_adsr.c
+        radspa/standard_plugin_lib/ampliverter.c
+        radspa/standard_plugin_lib/sampler.c
+        radspa/standard_plugin_lib/delay.c
+        radspa/standard_plugin_lib/flanger.c
+        radspa/standard_plugin_lib/multipitch.c
+        radspa/standard_plugin_lib/trigger_merge.c
+        radspa/standard_plugin_lib/sequencer.c
+        radspa/standard_plugin_lib/noise.c
+        radspa/standard_plugin_lib/noise_burst.c
+        radspa/standard_plugin_lib/distortion.c
+        radspa/standard_plugin_lib/lowpass.c
+        radspa/standard_plugin_lib/filter.c
+        radspa/standard_plugin_lib/mixer.c
+        radspa/standard_plugin_lib/range_shifter.c
+        radspa/standard_plugin_lib/poly_squeeze.c
+        radspa/standard_plugin_lib/slew_rate_limiter.c
+        radspa/standard_plugin_lib/buffer.c
+        plugins/bl00mbox_specific/bl00mbox_line_in.c
+        plugins/bl00mbox_specific/bl00mbox_channel_plugin.c
+        radspa/radspa_helpers.c
+        extern/xoroshiro64star.c
+    INCLUDE_DIRS
+        include
+        plugins
+        plugins/bl00mbox_specific
+        radspa
+        radspa/standard_plugin_lib
+        extern
+        config
+)

components/bl00mbox/LICENSE

+Creative Commons Legal Code
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