pkg/nanors: add reed solomon codec implementation

pkg/nanors/Makefile

@@ -0,0 +1,12 @@
+PKG_NAME=nanors
+PKG_URL=https://github.com/sleepybishop/nanors.git
+PKG_VERSION=389007b64a66f1c0c38c13bc510da1173cfe6097
+PKG_LICENSE=MIT
+
+include $(RIOTBASE)/pkg/pkg.mk
+
+# disable large look-up tables
+CFLAGS += -DOBLAS_TINY
+
+all:
+	$(QQ)"$(MAKE)" -C $(PKG_SOURCE_DIR) -f $(RIOTBASE)/Makefile.base

pkg/nanors/Makefile.include

@@ -0,0 +1,2 @@
+INCLUDES += -I$(PKGDIRBASE)/nanors
+INCLUDES += -I$(PKGDIRBASE)/nanors/deps/obl

pkg/nanors/doc.txt

@@ -0,0 +1,6 @@
+/**
+ * @defgroup pkg_nanors small Reed-Solomon code implementation
+ * @ingroup  pkg
+ * @brief    Provides a tiny, performant implementation of reed solomon codes
+ * @see      https://github.com/sleepybishop/nanors
+ */

tests/pkg_nanors/Makefile

@@ -0,0 +1,6 @@
+include ../Makefile.tests_common
+
+USEPKG += nanors
+USEMODULE += random
+
+include $(RIOTBASE)/Makefile.include

tests/pkg_nanors/Makefile.ci

@@ -0,0 +1,13 @@
+BOARD_INSUFFICIENT_MEMORY := \
+    arduino-uno \
+    atmega328p-xplained-mini \
+    atmega328p \
+    nucleo-l011k4 \
+    arduino-nano \
+    arduino-leonardo \
+    samd10-xmini \
+    arduino-duemilanove \
+    nucleo-f031k6 \
+    stm32f030f4-demo \
+    stk3200 \
+    #

tests/pkg_nanors/main.c

@@ -0,0 +1,91 @@
+/*
+ * Copyright (C) 2022 ML!PA Consulting GmbH
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     tests
+ * @{
+ *
+ * @file
+ * @brief       Test application for Reed-Solomon codec
+ *
+ * @author      Benjamin Valentin <benjamin.valentin@ml-pa.com>
+ * @}
+ */
+
+#include <stdio.h>
+#include <string.h>
+
+#include "kernel_defines.h"
+#include "random.h"
+#include "rs.h"
+
+#define DATA_SHARDS     20
+#define RECOVERY_SHARDS 10
+#define SHARD_SIZE      64
+
+typedef reed_solomon rs_t;
+
+int main(void)
+{
+    /* data + recovery */
+    static uint8_t data[(DATA_SHARDS + RECOVERY_SHARDS) * SHARD_SIZE];
+    /* copy of data for comparison */
+    static uint8_t data_cmp[DATA_SHARDS * SHARD_SIZE];
+    /* pointer to shards */
+    static uint8_t *shards[DATA_SHARDS + RECOVERY_SHARDS];
+    /* map of missing shards */
+    static uint8_t marks[DATA_SHARDS + RECOVERY_SHARDS];
+
+    /* generate random data */
+    random_bytes(data, sizeof(data_cmp));
+    memcpy(data_cmp, data, sizeof(data_cmp));
+
+    /* set up shard pointers */
+    for (unsigned i = 0; i < ARRAY_SIZE(shards); ++i) {
+        shards[i] = &data[i * SHARD_SIZE];
+    }
+
+    puts("START");
+    reed_solomon_init();
+    rs_t *rs = reed_solomon_new(DATA_SHARDS, RECOVERY_SHARDS);
+    if (!rs) {
+        puts("failed to init codec");
+        return -1;
+    }
+
+    printf("total: %u shards (%u bytes)\n",
+           (unsigned)ARRAY_SIZE(marks), (unsigned)sizeof(data));
+
+    /* generate parity shards */
+    reed_solomon_encode(rs, shards, ARRAY_SIZE(shards), SHARD_SIZE);
+
+    /* delete up to N shards */
+    for (unsigned i = 0; i < RECOVERY_SHARDS; i++) {
+        unsigned at = random_uint32_range(0, ARRAY_SIZE(shards));
+        printf("clear shard %u (%u byte)\n", at, SHARD_SIZE);
+        memset(shards[at], 0, SHARD_SIZE);
+        marks[at] = 1;
+    }
+
+    puts("reconstruct…");
+    if (reed_solomon_reconstruct(rs, shards, marks,
+                                 ARRAY_SIZE(shards), SHARD_SIZE)) {
+        puts("failed.");
+    } else {
+        puts("done.");
+    }
+    reed_solomon_release(rs);
+
+    if (memcmp(data, data_cmp, sizeof(data_cmp))) {
+        puts("FAILED");
+    } else {
+        puts("SUCCESS");
+    }
+
+    return 0;
+}

tests/pkg_nanors/tests/01-run.py

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+#!/usr/bin/env python3
+
+import sys
+from testrunner import run
+
+
+def testfunc(child):
+    child.expect_exact('START')
+    child.expect_exact('SUCCESS')
+
+
+if __name__ == "__main__":
+    sys.exit(run(testfunc))