add README.md [skip ci]

.drone.starlark

@@ -7,22 +7,39 @@ def main(ctx):
 		"steps": [
 			{
 				"name": "update submodules",
+				"image": "alpine/git",
+				"pull": "always",
+				"depends_on": ["clone"],
+				"commands": [
+					"git --version",
+					"git submodule update --init --recursive"
+				]
+			},
+			{
+				"name": "pull archlinux",
+				"image": "docker.io/archlinux:base-devel",
+				"pull": "always",
+				"depends_on": ["clone"],
+				"commands": [
+					"uname -r",
+				]
+			},
+			{
+				"name": "pull fedora-cpp",
 				"image": "docker.io/immawanderer/fedora-cpp:linux-amd64",
 				"pull": "always",
 				"depends_on": ["clone"],
 				"commands": [
 					"uname -r",
-					"git submodule update --init --recursive"
 				]
 			},
 			{
 				"name": "cppcheck",
 				"image": "docker.io/archlinux:base-devel",
-				"pull": "always",
-				"depends_on": ["update submodules"],
+				"pull": "if-not-exists",
+				"depends_on": ["update submodules", "pull archlinux"],
 				"commands": [
 					"pacman -Sy cppcheck --noconfirm --needed",
-					"uname -r",
 					"cppcheck --version",
 					"cppcheck --language=c++ --std=c++20 --enable=all --verbose ./*.{cpp,h}"
 				]
@@ -30,30 +47,27 @@ def main(ctx):
 			{
 				"name": "make debug",
 				"image": "docker.io/immawanderer/fedora-cpp:linux-amd64",
-				"pull": "always",
-				"depends_on": ["cppcheck"],
+				"pull": "if-not-exists",
+				"depends_on": ["cppcheck", "pull fedora-cpp"],
 				"commands": [
-					"uname -r",
 					"make debug"
 				]
 			},
 			{
 				"name": "make release",
 				"image": "docker.io/immawanderer/fedora-cpp:linux-amd64",
-				"pull": "always",
-				"depends_on": ["cppcheck"],
+				"pull": "if-not-exists",
+				"depends_on": ["cppcheck", "pull fedora-cpp"],
 				"commands": [
-					"uname -r",
 					"make release"
 				]
 			},
 			{
 				"name": "make san",
 				"image": "docker.io/immawanderer/fedora-cpp:linux-amd64",
-				"pull": "always",
-				"depends_on": ["cppcheck"],
+				"pull": "if-not-exists",
+				"depends_on": ["cppcheck", "pull fedora-cpp"],
 				"commands": [
-					"uname -r",
 					"make san"
 				]
 			}

LICENSE

@@ -2,7 +2,7 @@ GNU GENERAL PUBLIC LICENSE
 
 Version 3, 29 June 2007
 
-Copyright © 2021 Adam Mirre <a_mirre@utb.cz>
+Copyright © 2021-2022 Adam Mirre <a_mirre@utb.cz>
 
 Everyone is permitted to copy and distribute verbatim copies of this license
 document, but changing it is not allowed.

README.md

@@ -0,0 +1,121 @@
+# [`fortuna`](https://git.dotya.ml/wanderer/fortuna)
+
+[![pre-commit](https://img.shields.io/badge/pre--commit-enabled-brightgreen?logo=pre-commit&logoColor=white)](https://github.com/pre-commit/pre-commit)
+[![Build Status](https://drone.dotya.ml/api/badges/wanderer/fortuna/status.svg?ref=refs/heads/development)](https://drone.dotya.ml/wanderer/fortuna)
+
+this repo contains the *sawce* of the Fortuna CSPRNG implementation in C++.
+
+multi-threaded.<br>
+adherent to C++20 (best effort).<br>
+handles OS signals (`SIGINT`, `SIGTERM`, `SIGUSR1`, `SIGUSR2`).
+
+the following asciicast shows fortuna provide a 100MiB of pseudo-random data
+along with useful debug insights on data retrieval times,
+the [`reseed_ctr`](https://git.dotya.ml/wanderer/fortuna/src/commit/055fba29fe44e23730fe1ec493e16d0dc23dd3c1/accumulator.h#L27),
+bytes remaining, and Pool 0 (`p0`) size:
+[![asciicast](https://asciinema.org/a/V0fK2O8ahMMN2VFebAvkq4BIb.svg)](https://asciinema.org/a/V0fK2O8ahMMN2VFebAvkq4BIb)
+
+## validation
+to ensure a fundamental soundness of the implementation, fortuna output has
+been statistically analysed using:
+* [`dieharder` - *A Random Number Test Suite* (v3.31.1)](https://webhome.phy.duke.edu/~rgb/General/dieharder.php) -
+  on a ~243GiB stream of random material that the program kept producing until
+  `dieharder` finished testing ([log](https://git.dotya.ml/attachments/31f4fc32-f479-4bba-8359-02476bfa7e34))<br>
+  command used:
+  ```shell
+  ➜ fortuna | dieharder -a -g 200 -k 2 -Y 1
+  ```
+  parameter explanation:
+    * `-a`: runs all available tests (including some from NIST's STS)
+    * `-g 200`: a special mode to read raw data from standard input (where
+      fortuna outputs its stream)
+    * `-k 2`: speed and precision of sample reading, set to slow and precise:
+      > 2 is slower still, but (we hope) accurate to machine precision for any
+      > number of psamples up to some as yet unknown numerical upper limit (it
+      > has been tested out to at least hundreds of thousands).
+    * `-Y 1`: `Xtrategy` flag for the "test to failure" mode - set to
+      ["resolve ambiguity" (RA)](https://git.dotya.ml/ak-fortuna/presentation/raw/commit/53294f9e346a5122705ca2d61a659ca0b6047323/img/dieharder-xtrategy.png)
+
+  dieharder warning:
+  > **NOTE WELL:** The assessment(s) for the rngs may, in fact, be completely
+  > incorrect or misleading.
+  > There are still "bad tests" in dieharder, although we are working to fix
+  > and improve them (and try to document them in the test descriptions visible
+  > with -g testnumber -h).
+  > In particular, 'Weak' pvalues should occur one test in two hundred, and
+  > 'Failed' pvalues should occur one test in a million with the default
+  > thresholds - that's what p MEANS.
+  > Use them at your Own Risk!
+  > Be Warned!
+
+  that is, it appears fortuna can withstand this *"dieharder battery of tests"*.
+
+* [`ent` - *A Pseudorandom Number Sequence Test Program*](https://www.fourmilab.ch/random/) -
+  on a sample of 1000MiB of random data
+  ![ent run](https://git.dotya.ml/ak-fortuna/presentation/raw/commit/53294f9e346a5122705ca2d61a659ca0b6047323/img/ent1000M.png)
+
+### disclaimer
+note that this project is a direct continuation of the [semestral work](https://git.dotya.ml/ak-fortuna/fortuna)
+originally created for my Applied Cryptography university course, which has
+since been archived as the course had concluded.
+
+> ⚠  polite warning:
+> this code is not production-ready and has not been *professionally* and
+> *thoroughly* vetted.
+>
+> be advised that while I do believe the implementation to be correct and
+> valid, I would still recommend AGAINST USING this program to get entropy for
+> any serious purpose, since the code has not undergone proper peer review.
+
+please, be kind. this is my first *larger-than-main.cpp* C++ effort.
+
+## build 🔨
+### build-time dependencies
+* c++ compiler (note: only tested on fedora 35,36 and archlinux with `g++` and
+  `clang++` (versions ~12.2.1 and ~14.0.5, respectively)
+* [`ninja`](https://ninja-build.org/)
+* CMake
+* `make`
+* `libc++` (only tested with [`libcxx`](https://libcxx.llvm.org/))
+* `libc`
+* `libm`
+* [`cryptopp`](https://cryptopp.com/)
+* `lib{a,l,t,ub}san` on fedora, `gcc-libs` on archlinux
+* [`{fmt}`](https://fmt.dev/latest/index.html) - this one's also present as a
+  submodule at `lib/fmt` and automatically used if `fmtlib` is not already
+  present on the system.
+* `ldd` - optional
+* `git`
+* implicitly `pkg-conf` to look for all the libraries
+
+### runtime dependencies
+* `libc++`
+* `libm`
+* `cryptopp`
+
+### make targets
+there are multiple targets available in the [Makefile](Makefile) that allow for
+a relatively straightforward (definitely room for improvement) development
+experience without the need to type `g++` or (CMake, for that matter)
+incantations directly:
+* `make clean` - cleans up build objects, `ninja` and CMake-generated files
+* `make build` - a synonym for CMake's debug build (also `make debug`)
+* `make release` - builds a release-optimised binary
+* `make san` - builds a binary with [sanitizers](https://www.usenix.org/sites/default/files/conference/protected-files/enigma_slides_serebryany.pdf)
+* `make tidy` - builds a binary with `clang tidy` checks
+* `make check` - checks code using `cppcheck` and runs `make tidy`
+* `make test` - doesn't run *actual* tests (🙈), instead checks code with `make check`
+  and then builds a debug binary
+* `make distclean` - scrapes CMake build files from build directories
+
+the debug/release/san targets each have a `clang++` variant available, suffixed
+`_cl`, such that, e.g. `make debug_cl` would build a debug binary with `clang++`.
+
+### code formatting
+see [.clang-format](.clang-format)
+```shell
+➜ clang-format *.cpp *.h
+```
+
+## LICENSE
+GPL-3.0-or-later (see [LICENSE](LICENSE) for details).

lib/fmt

@@ -1 +1 @@
-Subproject commit c28500556a027fc3b84dc06e0021c719480fd1f3
+Subproject commit a33701196adfad74917046096bf5a2aa0ab0bb50

meson.build

@@ -26,6 +26,10 @@ sources = [
   'do_task.cpp',
   ]
 
+if get_option('buildtype').startswith('release')
+    add_project_arguments('-DNDEBUG', language : ['cpp'])
+endif
+
 cc_args = ['-std=c++20']
 incdir = include_directories('.')