Maintainability & housekeeping

* use meson for finding deps & building
* remove unmaintained macro-based build options
  * liquid-dsp and sndfile are now actual dependencies
* add .clang-format
* add build check pipeline

.clang-format

@@ -0,0 +1,18 @@
+---
+BasedOnStyle: Google
+IndentWidth: 2
+---
+Language: Cpp
+Standard: c++14
+ColumnLimit: 100
+AllowShortIfStatementsOnASingleLine: false
+AlignArrayOfStructures: Left
+AlignConsecutiveAssignments: Consecutive
+AllowShortFunctionsOnASingleLine: Empty
+AllowShortCaseLabelsOnASingleLine: true
+AlignConsecutiveShortCaseStatements:
+  Enabled: true
+  AcrossEmptyLines: true
+AlignConsecutiveDeclarations:
+  Enabled: true
+IncludeBlocks: Preserve

.github/workflows/build.yml

@@ -0,0 +1,86 @@
+name: build
+
+on:
+  push:
+    branches: [ master, dev ]
+    tags: [ 'v*' ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  build-ubuntu-22-04:
+    runs-on: ubuntu-22.04
+
+    steps:
+    - uses: actions/checkout@v4
+    - name: Install dependencies (apt)
+      run: sudo apt install python3-pip ninja-build libsndfile1-dev libliquid-dev
+    - name: Install meson (pip3)
+      run: pip3 install --user meson
+    - name: Compile via makefile
+      run: make
+    - name: meson setup
+      run: meson setup -Dwerror=true build
+    - name: meson compile
+      run: cd build && meson compile
+
+  build-ubuntu-20-04:
+    runs-on: ubuntu-20.04
+
+    steps:
+    - uses: actions/checkout@v4
+    - name: Install dependencies (apt)
+      run: sudo apt install python3-pip ninja-build libsndfile1-dev libliquid-dev
+    - name: Install meson (pip3)
+      run: pip3 install --user meson
+    - name: Compile via makefile
+      run: make
+    - name: meson setup
+      run: meson setup -Dwerror=true build
+    - name: meson compile
+      run: cd build && meson compile
+
+  build-debian-oldoldstable:
+    runs-on: ubuntu-latest
+    container: debian:buster
+
+    steps:
+    - uses: actions/checkout@v4
+    - name: Install dependencies (apt-get)
+      run: apt-get update && apt-get -y install python3-pip ninja-build build-essential libsndfile1-dev libliquid-dev
+    - name: Install meson (pip3)
+      run: pip3 install --user meson
+    - name: Compile via makefile
+      run: make
+    - name: meson setup
+      run: export PATH=$PATH:$HOME/.local/bin && meson setup -Dwerror=true build
+    - name: meson compile
+      run: export PATH=$PATH:$HOME/.local/bin && cd build && meson compile
+
+  build-macos:
+    runs-on: macos-latest
+
+    steps:
+    - uses: actions/checkout@v4
+    - name: Install dependencies (brew)
+      run: brew install meson libsndfile liquid-dsp
+    - name: Compile via makefile
+      run: make
+    - name: meson setup
+      run: meson setup -Dwerror=true build
+    - name: meson compile
+      run: cd build && meson compile
+
+  test:
+      runs-on: ubuntu-22.04
+
+      steps:
+      - uses: actions/checkout@v4
+      - name: Install dependencies (apt)
+        run: sudo apt install meson libsndfile1-dev libliquid-dev perl sox
+      - name: meson setup
+        run: meson setup -Dwerror=true build
+      - name: meson compile
+        run: cd build && meson compile
+      - name: test
+        run: cd test && perl test.pl

CHANGES.md

@@ -1,5 +1,18 @@
 # deinvert changelog
 
+## 1.0 (2024)
+
+* Maintenance release; no new features
+* Long-term maintainability:
+  * Add basic end-to-end tests, .clang-format, and build check pipelines
+  * Use meson (instead of autotools - which stopped working for me) to find deps & build
+  * Remove unmaintained macro-based build options
+    * liquid-dsp and sndfile are now actual dependencies
+* Fixes:
+  * Default-initialize buffers
+* Documentation:
+  * There is a [wiki](https://github.com/windytan/deinvert/wiki) and more (in-)security reminders
+
 ## 0.3 (2018-05-31)
 
 * Reduce artifacts from DC removal filter at startup
@@ -8,4 +21,3 @@
 ## 0.2 (2018-01-03)
 
 * Add DC removal filter to fix 'beeping' issues
-

README.md

@@ -11,28 +11,28 @@ instructions and examples.
 
 ## Prerequisites
 
-By default, deinvert requires liquid-dsp, libsndfile, and GNU autotools. On
-Ubuntu, these can be installed like so:
+deinvert requires liquid-dsp, libsndfile, and meson.
 
-    sudo apt install libsndfile1-dev libliquid-dev automake
+On Ubuntu, these can be installed like so:
+
+    sudo apt install libsndfile1-dev libliquid-dev meson
+
+On older Debians:
+
+    sudo apt-get install python3-pip ninja-build build-essential libsndfile1-dev libliquid-dev
+    pip3 install --user meson
     sudo ldconfig
 
 On macOS I recommend using [homebrew](https://brew.sh/):
 
     xcode-select --install
-    brew install libsndfile liquid-dsp automake
-
-But deinvert can be compiled without liquid-dsp using the configure
-option `--without-liquid`; filtering will be disabled and the result will not
-sound as good. It can also be compiled
-without libsndfile using the configure option `--without-sndfile`; WAV
-support will be disabled, only raw input/output will work.
+    brew install libsndfile liquid-dsp meson
 
 ## Compiling
 
-    ./autogen.sh
-    ./configure [--without-liquid] [--without-sndfile]
-    make
+    meson setup build
+    cd build
+    meson compile
 
 ## Usage
 
@@ -47,19 +47,19 @@ and outputs in the same format via stdout. The inversion carrier defaults to
 
 (De)scrambling a WAV file with setting 4:
 
-    ./src/deinvert -i input.wav -o output.wav -p 4
+    ./build/deinvert -i input.wav -o output.wav -p 4
 
 ### Split-band inversion
 
 (De)scrambling split-band inversion with a bandwidth of 3500 Hz, split at 1200 Hz:
 
-    ./src/deinvert -i input.wav -o output.wav -f 3500 -s 1200
+    ./build/deinvert -i input.wav -o output.wav -f 3500 -s 1200
 
 ### Invert a live signal from RTL-SDR
 
 Descrambling a live FM channel at 27 Megahertz from an RTL-SDR, setting 4:
 
-    rtl_fm -M fm -f 27.0M -s 12k -g 50 -l 70 | ./src/deinvert -r 12000 -p 4 |\
+    rtl_fm -M fm -f 27.0M -s 12k -g 50 -l 70 | ./build/deinvert -r 12000 -p 4 |\
       play -r 12k -c 1 -t .s16 -
 
 ### Invert a live signal from Gqrx (requires netcat)
@@ -70,12 +70,12 @@ Descrambling a live FM channel at 27 Megahertz from an RTL-SDR, setting 4:
 4. In the Audio window, enable UDP.
 5. Run this command in a terminal window:
 
-    nc -u -l localhost 12345 | ./src/deinvert -r 48000 | play -r 48k -c 1 -t .s16 -
+    nc -u -l localhost 12345 | ./build/deinvert -r 48000 | play -r 48k -c 1 -t .s16 -
 
 
 ### Full options
 
-    ./src/deinvert [OPTIONS]
+    ./build/deinvert [OPTIONS]
 
     -f, --frequency FREQ   Frequency of the inversion carrier, in Hertz.
 
@@ -86,6 +86,7 @@ Descrambling a live FM channel at 27 Megahertz from an RTL-SDR, setting 4:
 
     -o, --output-file FILE Write output to a WAV file instead of stdout. An
                            existing file will be overwritten.
+                           The input sample rate will be used.
 
     -p, --preset NUM       Scrambler frequency preset (1-8), referring to
                            the set of common carrier frequencies used by
@@ -116,18 +117,11 @@ Descrambling a live FM channel at 27 Megahertz from an RTL-SDR, setting 4:
 
 ## Troubleshooting
 
-### Can't find liquid-dsp on macOS
-
-If you've installed liquid-dsp yet `configure` can't find it, it's possible that
-XCode command line tools aren't installed. Run this command to fix it:
+### I can't understand the speech even after deinverting
 
-    xcode-select --install
-
-### Can't find liquid-dsp on Linux
-
-Try running this in the terminal:
-
-    sudo ldconfig
+In this case, the sample is probably not frequency inversion scrambled.
+It's very rare to encounter frequency inversion scrambling nowadays. See the
+[wiki](https://github.com/windytan/deinvert/wiki) for details.
 
 ### I hear a high-pitched beep in the result
 

meson.build

@@ -0,0 +1,65 @@
+project(
+  'deinvert',
+  'cpp',
+  default_options: ['warning_level=3', 'buildtype=release', 'optimization=3'],
+  version: '1.0',
+)
+
+# Store version number to be compiled in
+conf = configuration_data()
+conf.set_quoted('VERSION', meson.project_version())
+configure_file(output: 'config.h', configuration: conf)
+
+########################
+### Compiler options ###
+########################
+
+cc = meson.get_compiler('cpp')
+add_project_arguments(cc.get_supported_arguments(['-Wno-unknown-pragmas']), language: 'cpp')
+
+# We want to use M_PI on Windows
+if build_machine.system() == 'windows'
+  add_project_arguments('-D_USE_MATH_DEFINES=1', language: 'cpp')
+endif
+
+# Explicit GNU extensions on Cygwin
+if build_machine.system() == 'cygwin'
+  add_project_arguments('-std=gnu++14', language: 'cpp')
+else
+  add_project_arguments('-std=c++14', language: 'cpp')
+endif
+
+####################
+### Dependencies ###
+####################
+
+# Find libsndfile
+sndfile = dependency('sndfile')
+
+# Find liquid-dsp
+if build_machine.system() == 'darwin'
+  fs = import('fs')
+  # Homebrew system
+  if fs.is_dir('/opt/homebrew/lib')
+    liquid_lib = cc.find_library('liquid', dirs: ['/opt/homebrew/lib'])
+    liquid_inc = include_directories('/opt/homebrew/include')
+    # MacPorts system
+  else
+    liquid_lib = cc.find_library('liquid', dirs: ['/opt/local/lib'])
+    liquid_inc = include_directories('/opt/local/include')
+  endif
+  liquid = declare_dependency(dependencies: liquid_lib, include_directories: liquid_inc)
+else
+  liquid = cc.find_library('liquid')
+endif
+
+############################
+### Sources & Executable ###
+############################
+
+sources = [
+  'src/deinvert.cc',
+  'src/liquid_wrappers.cc',
+]
+
+executable('deinvert', sources, dependencies: [liquid, sndfile], install: true)