Limit the RSSI call to just reading the variable without running a test

Add a missing declaration

dio/dio.h

@@ -3,11 +3,11 @@ Copyright 2022, Savanni D'Gerinel <savanni@luminescent-dreams.com>
 
 This file is part of Savanni's AVR library.
 
-Lumeto is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+This AVR library is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
 
-Lumeto 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 General Public License for more details.
+This AVR library 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 General Public License for more details.
 
-You should have received a copy of the GNU General Public License along with Lumeto. If not, see <https://www.gnu.org/licenses/>.
+You should have received a copy of the GNU General Public License along with this AVR library. If not, see <https://www.gnu.org/licenses/>.
 */
 
 #ifndef __BASE_H__

flake.nix

@@ -34,7 +34,12 @@
                   ${gcc} ${cflags} ${include_dirs} -c $source
               fi
           done
-          cp ${src}/*.h . || true
+          for source in ${src}/src/*.c; do
+              if [ -e $source ]; then
+                  ${gcc} ${cflags} ${include_dirs} -c $source
+              fi
+          done
+          cp ${src}/*.h ${src}/src/*.h . || true
           '';
 
         installPhase = ''
@@ -44,15 +49,16 @@
           '';
       };
 
-      mkProgram = { pkgs, gcc, cflags, pname, psrc, pbuildInputs ? [] }:
+      mkProgram = { pkgs, gcc, cflags, pname, psrc, pbuildInputs ? [], pnativeBuildInputs ? [] }:
       pkgs.stdenv.mkDerivation rec {
         name = pname;
         src = psrc;
 
         buildInputs = pbuildInputs;
+        nativeBuildInputs = pnativeBuildInputs;
 
-        include_dirs = pkgs.lib.concatStringsSep " " (map (dir: "-I${dir}/include") buildInputs);
+        include_dirs = pkgs.lib.concatStringsSep " " (map (dir: "-I${dir}/include") pbuildInputs);
-        object_files = pkgs.lib.concatStringsSep " " (map (dir: "${dir}/lib/*.o") buildInputs);
+        object_files = pkgs.lib.concatStringsSep " " (map (dir: "${dir}/lib/*.o") pbuildInputs);
 
         dontUnpack = true;
         dontConfigure = true;
@@ -73,6 +79,35 @@
           '';
       };
 
+      mkTests = { pkgs, gcc, cflags, pname, psrc, pbuildInputs ? [], pnativeBuildInputs ? [] }:
+      pkgs.stdenv.mkDerivation rec {
+        name = pname;
+        src = psrc;
+
+        buildInputs = pbuildInputs;
+        nativeBuildInputs = pnativeBuildInputs;
+
+        include_dirs = pkgs.lib.concatStringsSep " " (map (dir: "-I${dir}/include") buildInputs);
+        object_files = pkgs.lib.concatStringsSep " " (map (dir: "${dir}/lib/*.o") buildInputs);
+
+        dontUnpack = true;
+        dontConfigure = true;
+
+        buildPhase = ''
+          for source in ${src}/tests/*.c; do
+              if [ -e $source ]; then
+                  ${gcc} ${cflags} ${include_dirs} -c $source
+              fi
+          done
+
+          ${gcc} -o ${name} ${cflags} ${object_files} *.o
+          '';
+
+        installPhase = ''
+          mkdir -p $out/bin
+          cp ${name} $out/bin
+          '';
+      };
 
     in rec
     {
@@ -85,22 +120,11 @@
           paths = [
             (packages."x86_64-linux"."prime-tx" { gcc = "${avr.gcc}/bin/avr-gcc"; cflags = mcu_cflags atmega32u4; })
             (packages."x86_64-linux"."radio-rx" { gcc = "${avr.gcc}/bin/avr-gcc"; cflags = mcu_cflags atmega32u4; })
+            (packages."x86_64-linux"."packet-radio" { gcc = "${avr.gcc}/bin/avr-gcc"; cflags = "-Wall -Werror"; })
+            (packages."x86_64-linux"."packet-radio-tests" { gcc = "${avr.gcc}/bin/avr-gcc"; cflags = "-Wall -Werror"; })
           ];
         };
 
-      /* packages."x86_64-linux"."dio-attiny85" = (packages."x86_64-linux"."dio" attiny85); */
-
-      /*
-      packages."x86_64-linux"."dio" =
-        let
-          pkgs = import nixpkgs { system = "x86_64-linux"; };
-        in mkLibrary {
-          mkDerivation = pkgs.stdenv.mkDerivation;
-          gcc =
-          cflags = 
-          name =
-      */
-
       packages."x86_64-linux"."dio" =
         { gcc, cflags }:
         let
@@ -214,6 +238,47 @@
           ];
         };
 
+      packages."x86_64-linux"."packet-radio_" =
+        let
+          pkgs = import nixpkgs { system = "x86_64-linux"; };
+        in packages."x86_64-linux"."packet-radio" { gcc = "${pkgs.gcc}/bin/gcc"; cflags = "-Wall -Werror"; };
+
+      packages."x86_64-linux"."packet-radio" =
+        { gcc, cflags }:
+        let
+          pkgs = import nixpkgs { system = "x86_64-linux"; };
+        in mkLibrary {
+          pkgs = pkgs;
+          gcc = gcc;
+          cflags = cflags;
+          pname = "packet-radio";
+          psrc = ./packet-radio;
+          pbuildInputs = [ ];
+        };
+
+      packages."x86_64-linux"."packet-radio-tests_" =
+        let
+          pkgs = import nixpkgs { system = "x86_64-linux"; };
+        in packages."x86_64-linux"."packet-radio-tests" { gcc = "${pkgs.gcc}/bin/gcc"; cflags = "-Wall -Werror -lcriterion"; };
+
+      packages."x86_64-linux"."packet-radio-tests" =
+        { gcc, cflags }:
+        let
+          pkgs = import nixpkgs { system = "x86_64-linux"; };
+        in mkTests {
+          pkgs = pkgs;
+          gcc = gcc;
+          cflags = cflags;
+          pname = "packet-radio-tests";
+          psrc = ./packet-radio;
+          pbuildInputs = [
+            (packages."x86_64-linux"."packet-radio" { inherit gcc cflags; })
+          ];
+          pnativeBuildInputs = [
+            pkgs.criterion
+          ];
+        };
+
       packages."x86_64-linux"."prime-tx" =
         { gcc, cflags }:
         let
@@ -262,6 +327,7 @@
             avrdude
             simavr
             gtkwave
+            criterion
           ];
         in
         pkgs.mkShell {

packet-radio/src/packet.h

@@ -0,0 +1,36 @@
+/*
+Copyright 2022, Savanni D'Gerinel <savanni@luminescent-dreams.com>
+
+This file is part of Savanni's AVR library.
+
+This AVR library is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+
+This AVR library 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License along with this AVR library. If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#ifndef __PACKET_H__
+#define __PACKET_H__
+
+#include <stdint.h>
+#include <stdlib.h>
+#include <stdbool.h>
+
+typedef enum {
+    packet_type_data,
+    packet_type_ack,
+    packet_type_retry,
+} packet_type_e;
+
+typedef struct {
+    packet_type_e type;
+    uint16_t count;
+    uint8_t sender;
+    uint8_t receiver;
+    size_t length;
+    char message[60];
+} packet_t;
+
+#endif
+

packet-radio/src/packet_buffer.c

@@ -0,0 +1,81 @@
+/*
+Copyright 2022, Savanni D'Gerinel <savanni@luminescent-dreams.com>
+
+This file is part of Savanni's AVR library.
+
+This AVR library is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+
+This AVR library 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License along with this AVR library. If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#include "radio.h"
+#include "packet_buffer.h"
+// #include <stdlib.h>
+// #include <string.h>
+
+size_t circular_next(size_t current, size_t max);
+
+packet_buffer_t *packet_buffer_new(void) {
+    packet_buffer_t *buffer = malloc(sizeof(packet_buffer_t));
+    packet_buffer_init(buffer);
+    return buffer;
+}
+
+void packet_buffer_init(packet_buffer_t *buffer) {
+    buffer->count = 0;
+    buffer->bottom = 0;
+    buffer->top = 0;
+}
+
+packet_t *packet_buffer_enqueue(packet_buffer_t *self, packet_buffer_status_e *status) {
+    if (!IS_OK(status)) return NULL;
+
+    if (packet_buffer_is_full(self)) {
+        *status = packet_buffer_status_full;
+        return NULL;
+    }
+
+    packet_t *ptr = &self->buffer[self->top];
+    self->top = circular_next(self->top, 5);
+    self->count++;
+    return ptr;
+}
+
+packet_t *packet_buffer_head(packet_buffer_t *self, packet_buffer_status_e *status) {
+    if (!IS_OK(status)) return NULL;
+
+    if (packet_buffer_is_empty(self)) {
+        *status = packet_buffer_status_empty;
+        return NULL;
+    }
+
+    return &self->buffer[self->bottom];
+}
+
+void packet_buffer_dequeue(packet_buffer_t *self, packet_buffer_status_e *status) {
+    if (!IS_OK(status)) return;
+
+    if (packet_buffer_is_empty(self)) {
+        *status = packet_buffer_status_empty;
+        return;
+    }
+
+    self->bottom = circular_next(self->bottom, 5);
+    self->count--;
+}
+
+bool packet_buffer_is_full(packet_buffer_t *self) {
+    return self->count == 5;
+}
+
+bool packet_buffer_is_empty(packet_buffer_t *self) {
+    return self->count == 0;
+}
+
+size_t circular_next(size_t current, size_t max) {
+    current++;
+    return (current < max) ? current : 0;
+}
+

packet-radio/src/packet_buffer.h

@@ -0,0 +1,41 @@
+/*
+Copyright 2022, Savanni D'Gerinel <savanni@luminescent-dreams.com>
+
+This file is part of Savanni's AVR library.
+
+This AVR library is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+
+This AVR library 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License along with this AVR library. If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#ifndef __PACKET_BUFFER_H__
+#define __PACKET_BUFFER_H__
+
+#include "packet.h"
+
+typedef enum {
+    packet_buffer_status_ok,
+    packet_buffer_status_empty,
+    packet_buffer_status_full,
+} packet_buffer_status_e;
+
+typedef struct {
+    size_t count;
+    size_t bottom;
+    size_t top;
+    packet_t buffer[5];
+} packet_buffer_t;
+
+packet_buffer_t *packet_buffer_new(void);
+void packet_buffer_init(packet_buffer_t *);
+
+packet_t * packet_buffer_enqueue(packet_buffer_t *, packet_buffer_status_e *);
+packet_t * packet_buffer_head(packet_buffer_t *, packet_buffer_status_e *);
+void packet_buffer_dequeue(packet_buffer_t *, packet_buffer_status_e *);
+
+bool packet_buffer_is_full(packet_buffer_t *);
+bool packet_buffer_is_empty(packet_buffer_t *);
+
+#endif

packet-radio/src/radio.c

@@ -0,0 +1,175 @@
+/*
+Copyright 2022, Savanni D'Gerinel <savanni@luminescent-dreams.com>
+
+This file is part of Savanni's AVR library.
+
+This AVR library is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+
+This AVR library 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License along with this AVR library. If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#include "radio.h"
+#include "packet.h"
+#include "packet_buffer.h"
+#include <string.h>
+
+struct conn_s {
+    uint16_t packet_counter;
+    uint8_t address;
+
+    packet_buffer_t outgoing;
+    packet_buffer_t incoming;
+
+    void (*set_mode)(radio_t *, radio_mode_e, radio_status_e *);
+    flags_t (*get_flags)(radio_t *, radio_status_e *);
+    void (*transmit)(radio_t *, packet_t *, radio_status_e *);
+    void (*receive)(radio_t *, uint8_t data[66], radio_status_e *);
+
+    radio_t *radio;
+};
+
+conn_t * conn_connect(radio_t *radio) {
+    conn_t *connection = malloc(sizeof(struct conn_s));
+    connection->packet_counter = 0;
+    connection->address = 0;
+
+    packet_buffer_init(&connection->outgoing);
+    packet_buffer_init(&connection->incoming);
+
+    connection->set_mode = radio->set_mode;
+    connection->get_flags = radio->get_flags;
+    connection->transmit = radio->transmit;
+    connection->receive = radio->receive;
+    connection->radio = radio;
+
+    return connection;
+}
+
+void conn_set_address(conn_t *self, uint8_t addr, radio_status_e *status) {
+    if (!IS_OK(status)) return;
+    self->address = addr;
+}
+
+void conn_set_mode(conn_t *self, radio_mode_e mode, radio_status_e *status) {
+    if (!IS_OK(status)) return;
+    self->set_mode(self->radio, mode, status);
+}
+
+flags_t conn_get_flags(conn_t *self, radio_status_e *status) {
+    if (!IS_OK(status)) return (flags_t){ .packet_sent = false, .packet_ready = false };
+    return self->get_flags(self->radio, status);
+}
+
+void conn_send(conn_t *self, uint8_t dest, msg_t *message, radio_status_e *status) {
+    if (!IS_OK(status)) return;
+
+    if (message->length > MAX_MESSAGE_LENGTH) {
+        *status = message_too_long;
+        return;
+    }
+
+    if (packet_buffer_is_full(&self->outgoing)) {
+        *status = outgoing_full;
+        return;
+    }
+
+    packet_buffer_status_e buffer_status = packet_buffer_status_ok;
+
+    packet_t *packet = packet_buffer_enqueue(&self->outgoing, &buffer_status);
+    if (!IS_OK(&buffer_status)) {
+        switch (buffer_status) {
+            case packet_buffer_status_full:
+                *status = outgoing_full;
+                break;
+            default:
+                *status = unhandled_error;
+                break;
+        }
+        return;
+    }
+
+    packet->type = packet_type_data;
+    packet->count = self->packet_counter;
+    packet->sender = self->address;
+    packet->receiver = dest;
+    packet->length = message->length;
+    memcpy(&packet->message, message->data, message->length);
+
+    self->transmit(self->radio, packet, status);
+    if (!IS_OK(status)) return;
+
+    return;
+}
+
+received_msg_t * conn_receive(conn_t *self, radio_status_e *status) {
+    if (!IS_OK(status)) return NULL;
+
+    if (packet_buffer_is_empty(&self->incoming)) {
+        *status = packet_buffer_status_empty;
+        return NULL;
+    }
+
+    packet_buffer_status_e buffer_status = packet_buffer_status_ok;
+    packet_t *packet = packet_buffer_head(&self->incoming, &buffer_status);
+    if (!IS_OK(&buffer_status)) {
+        // *status =
+    }
+
+    received_msg_t *msg = malloc(sizeof(received_msg_t) + packet->length);
+    msg->sender = packet->sender;
+    msg->message.length = packet->length;
+    memcpy(msg->message.data, packet->message, packet->length);
+
+    packet_buffer_dequeue(&self->incoming, &buffer_status);
+    if (!IS_OK(&buffer_status)) {
+    }
+
+    return msg;
+}
+
+void conn_handle_interrupt(conn_t *self) {
+    /*
+    radio_status_e *status = ok;
+
+    flags_t flags = self->get_flags(self->radio, status);
+    // if this is failing, we should raise a flag that indicates that the radio itself is in trouble
+    if (!IS_OK(status)) return;
+
+    if (flags.packet_ready) {
+        uint8_t data[66];
+        self->receive(self->radio, data, status);
+        // if this fails, increment an error counter
+        if (!IS_OK(status)) return;
+
+        packet_t *packet = (packet_t *)data;
+        if (packet->receiver != self->address) {
+            return;
+        }
+
+        switch (packet->type) {
+            case packet_type_data:
+                packet_buffer_status_e status;
+                packet_t *dest = packet_buffer_enqueue(self->incoming, &status);
+                memcpy(dest, packet, sizeof(packet_t) + packet->length);
+                break;
+            case packet_type_ack:
+                // uint16_t confirmed = packet->data[0] << 8 + packet->data[1];
+                // while (self->outgoing_buffer[self->outgoing_bottom]->count < confirmed && !is_empty(self->outgoing_buffer)
+                break;
+            case packet_type_retry:
+                break;
+        }
+        // process the packet type
+        // break;
+    }
+
+    // timeout processing
+    // if (time > receiving_timeout) { }
+    // if we were receiving data, a receiving_timeout must have been set. At this point, we're not receiving any more data, so it's time to send a confirmation.
+    // if (time > confirmation_timeout) { }
+    // if we were sending data, a confirmation timeout must have been set. But I don't recall what this is good for? Do we want to retransmit everything?
+    */
+}
+

packet-radio/src/radio.h

@@ -0,0 +1,75 @@
+/*
+Copyright 2022, Savanni D'Gerinel <savanni@luminescent-dreams.com>
+
+This file is part of Savanni's AVR library.
+
+This AVR library is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+
+This AVR library 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License along with this AVR library. If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#ifndef __RADIO_H__
+#define __RADIO_H__
+
+#include <stddef.h>
+#include "packet.h"
+
+#define MAX_MESSAGE_LENGTH 60
+#define IS_OK(val) (val == NULL || !*val)
+
+typedef struct {
+    size_t length;
+    char data[0];
+} msg_t;
+
+typedef struct {
+    uint16_t sender;
+    msg_t message;
+} received_msg_t;
+
+typedef enum {
+    ok,
+    not_found,
+    message_too_long,
+    outgoing_full,
+    unhandled_error,
+} radio_status_e;
+
+typedef struct conn_s conn_t;
+
+typedef enum {
+    sleep,
+    standby,
+    tx,
+    rx,
+    listen
+} radio_mode_e;
+
+typedef struct {
+    bool packet_sent;
+    bool packet_ready;
+} flags_t;
+
+typedef struct radio_s radio_t;
+
+struct radio_s {
+    void (*set_mode)(radio_t *, radio_mode_e, radio_status_e *);
+    flags_t (*get_flags)(radio_t *, radio_status_e *);
+    void (*transmit)(radio_t *, packet_t *, radio_status_e *);
+    void (*receive)(radio_t *, uint8_t data[66], radio_status_e *);
+};
+
+conn_t * conn_connect(radio_t *radio);
+
+void conn_set_address(conn_t *, uint8_t, radio_status_e *);
+void conn_set_mode(conn_t *, radio_mode_e, radio_status_e *);
+flags_t conn_get_flags(conn_t *, radio_status_e *);
+
+void conn_send(conn_t *, uint8_t, msg_t *, radio_status_e *);
+received_msg_t * conn_receive(conn_t *, radio_status_e *);
+
+// void radio_broadcast(conn_t *, uint16_t, msg_t *, radio_status_e *);
+
+#endif

packet-radio/tests/packet_buffer.c

@@ -0,0 +1,180 @@
+/*
+Copyright 2022, Savanni D'Gerinel <savanni@luminescent-dreams.com>
+
+This file is part of Savanni's AVR library.
+
+This AVR library is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+
+This AVR library 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License along with this AVR library. If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#include <criterion/criterion.h>
+#include <stdio.h>
+#include "packet_buffer.h"
+
+Test(packet_buffer, empty_buffer) {
+    packet_buffer_t *buffer = packet_buffer_new();
+    cr_assert(packet_buffer_is_empty(buffer));
+    cr_assert(!packet_buffer_is_full(buffer));
+}
+
+Test(packet_buffer, full_buffer) {
+    packet_buffer_status_e status = packet_buffer_status_ok;
+    packet_buffer_t *buffer = packet_buffer_new();
+    packet_t *packet;
+
+    packet = packet_buffer_enqueue(buffer, &status);
+    cr_assert(packet != NULL);
+    cr_assert(status == packet_buffer_status_ok);
+    cr_assert(!packet_buffer_is_empty(buffer));
+    cr_assert(!packet_buffer_is_full(buffer));
+
+    packet = packet_buffer_enqueue(buffer, &status);
+    cr_assert(packet != NULL);
+    cr_assert(status == packet_buffer_status_ok);
+
+    packet = packet_buffer_enqueue(buffer, &status);
+    cr_assert(packet != NULL);
+    cr_assert(status == packet_buffer_status_ok);
+
+    packet = packet_buffer_enqueue(buffer, &status);
+    cr_assert(packet != NULL);
+    cr_assert(status == packet_buffer_status_ok);
+
+    packet = packet_buffer_enqueue(buffer, &status);
+    cr_assert(packet != NULL);
+    cr_assert(status == packet_buffer_status_ok);
+    cr_assert(packet_buffer_is_full(buffer));
+
+    packet = packet_buffer_enqueue(buffer, &status);
+    cr_assert(packet == NULL);
+    cr_assert(status == packet_buffer_status_full);
+    cr_assert(packet_buffer_is_full(buffer));
+}
+
+Test(packet_buffer, basic_enqueue_and_dequeue) {
+    packet_buffer_status_e status = packet_buffer_status_ok;
+    packet_buffer_t *buffer = packet_buffer_new();
+    packet_t *packet;
+
+    packet = packet_buffer_enqueue(buffer, &status);
+    cr_assert(status == packet_buffer_status_ok);
+
+    packet->type = packet_type_data;
+    packet->count = 0;
+    packet->sender = 15;
+    packet->receiver = 16;
+    packet->length = 2;
+    memcpy(packet->message, (char [2]){ 25, 24 }, 2);
+
+    packet = packet_buffer_head(buffer, &status);
+    cr_assert(status == packet_buffer_status_ok);
+    cr_assert(packet->type == packet_type_data);
+    cr_assert(packet->count == 0);
+    cr_assert(packet->sender == 15);
+    cr_assert(packet->receiver == 16);
+    cr_assert(packet->length == 2);
+    cr_assert(packet->message[0] == 25);
+    cr_assert(packet->message[1] == 24);
+
+    packet_buffer_dequeue(buffer, &status);
+    cr_assert(status == packet_buffer_status_ok);
+}
+
+Test(packet_buffer, enqueue_to_full) {
+    packet_buffer_status_e status = packet_buffer_status_ok;
+    packet_buffer_t *buffer = packet_buffer_new();
+    packet_t *packet;
+
+    packet = packet_buffer_enqueue(buffer, &status);
+    cr_assert(status == packet_buffer_status_ok);
+
+    packet->type = packet_type_data;
+    packet->count = 0;
+    packet->sender = 15;
+    packet->receiver = 16;
+    packet->length = 2;
+    memcpy(packet->message, (char [2]){ 25, 24 }, 2);
+
+    packet = packet_buffer_enqueue(buffer, &status);
+    packet = packet_buffer_enqueue(buffer, &status);
+    packet = packet_buffer_enqueue(buffer, &status);
+    packet = packet_buffer_enqueue(buffer, &status);
+    cr_assert(status == packet_buffer_status_ok);
+
+    packet = packet_buffer_head(buffer, &status);
+    cr_assert(status == packet_buffer_status_ok);
+    cr_assert(packet->type == packet_type_data);
+    cr_assert(packet->count == 0);
+    cr_assert(packet->sender == 15);
+    cr_assert(packet->receiver == 16);
+    cr_assert(packet->length == 2);
+    cr_assert(packet->message[0] == 25);
+    cr_assert(packet->message[1] == 24);
+
+    packet_buffer_dequeue(buffer, &status);
+    cr_assert(status == packet_buffer_status_ok);
+}
+
+Test(packet_buffer, circular_buffer) {
+    packet_buffer_status_e status = packet_buffer_status_ok;
+    packet_buffer_t *buffer = packet_buffer_new();
+    packet_t *packet;
+
+    packet = packet_buffer_enqueue(buffer, &status);
+    packet = packet_buffer_enqueue(buffer, &status);
+    packet = packet_buffer_enqueue(buffer, &status);
+    packet->type = packet_type_data;
+    packet->count = 0;
+    packet->sender = 15;
+    packet->receiver = 16;
+    packet->length = 2;
+    memcpy(packet->message, (char [2]){ 25, 24 }, 2);
+
+    packet_buffer_dequeue(buffer, &status);
+    packet_buffer_dequeue(buffer, &status);
+
+    packet = packet_buffer_enqueue(buffer, &status);
+    packet = packet_buffer_enqueue(buffer, &status);
+    packet = packet_buffer_enqueue(buffer, &status);
+    packet = packet_buffer_enqueue(buffer, &status);
+    cr_assert(status == packet_buffer_status_ok);
+
+    packet->type = packet_type_data;
+    packet->count = 1;
+    packet->sender = 15;
+    packet->receiver = 16;
+    packet->length = 2;
+    memcpy(packet->message, (char [2]){ 25, 24 }, 2);
+
+    packet = packet_buffer_head(buffer, &status);
+    printf("packet-type: %d\n", packet->type);
+    cr_assert(status == packet_buffer_status_ok);
+    cr_assert(packet->type == packet_type_data);
+    cr_assert(packet->count == 0);
+    cr_assert(packet->sender == 15);
+    cr_assert(packet->receiver == 16);
+    cr_assert(packet->length == 2);
+    cr_assert(packet->message[0] == 25);
+    cr_assert(packet->message[1] == 24);
+
+    packet_buffer_dequeue(buffer, &status);
+    packet_buffer_dequeue(buffer, &status);
+    packet_buffer_dequeue(buffer, &status);
+    packet_buffer_dequeue(buffer, &status);
+    packet = packet_buffer_head(buffer, &status);
+    cr_assert(status == packet_buffer_status_ok);
+    cr_assert(packet->type == packet_type_data);
+    cr_assert(packet->count == 1);
+    cr_assert(packet->sender == 15);
+    cr_assert(packet->receiver == 16);
+    cr_assert(packet->length == 2);
+    cr_assert(packet->message[0] == 25);
+    cr_assert(packet->message[1] == 24);
+
+    packet_buffer_dequeue(buffer, &status);
+    cr_assert(status == packet_buffer_status_ok);
+    cr_assert(packet_buffer_is_empty(buffer));
+}

packet-radio/tests/radio.c

@@ -0,0 +1,46 @@
+/*
+Copyright 2022, Savanni D'Gerinel <savanni@luminescent-dreams.com>
+
+This file is part of Savanni's AVR library.
+
+This AVR library is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+
+This AVR library 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License along with this AVR library. If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#include <criterion/criterion.h>
+#include "radio.h"
+
+/*
+typedef struct {
+    void (*set_mode)(radio_mock_t *, radio_mode_e, radio_status_e *);
+    flags_t (*get_flags)(radio_mock_t *, radio_status_e *);
+    radio_mock_t (*transmit)(radio_mock_t *, packet_t *, radio_status_e *);
+    void (*receive)(radio_mock_t *, uint8_t data[66], radio_status_e *);
+} radio_mock_t;
+*/
+
+void set_mode(radio_t *radio, radio_mode_e mode, radio_status_e *status) { }
+
+flags_t get_flags(radio_t *radio, radio_status_e *status) {
+    flags_t flags = { .packet_sent = false, .packet_ready = false };
+    return flags;
+}
+
+void transmit(radio_t *radio, packet_t *packet, radio_status_e *status) { }
+
+void receive(radio_t *radio, uint8_t data[66], radio_status_e *status) { }
+
+Test(radio, connect) {
+    radio_t radio = (radio_t){ .set_mode = set_mode, .get_flags = get_flags, .transmit = transmit, .receive = receive };
+    conn_t *conn = conn_connect((radio_t *)&radio);
+
+    radio_status_e status = ok;
+    flags_t flags = conn_get_flags(conn, &status);
+    cr_assert(IS_OK(&status));
+    cr_assert(flags.packet_sent == false);
+    cr_assert(flags.packet_ready == false);
+}
+

rfm69hcw/rfm.c

@@ -327,19 +327,8 @@ interrupt_flags_t rfm_interrupts(rfm_t *rfm) {
 }
 
 uint8_t rfm_rssi(rfm_t *rfm) {
-    // uint8_t rssi_reg;
     uint8_t rssi_value;
-
-    /*
-    _rfm_write(rfm, REG_RSSI_CONFIG, (uint8_t [1]){ _BV(0) }, 1);
-
-    while(!(rssi_reg & _BV(1))) {
-        _rfm_read(rfm, REG_RSSI_CONFIG, &rssi_reg, 1);
-    }
-    */
-
     _rfm_read(rfm, REG_RSSI_VALUE, &rssi_value, 1);
-
     return rssi_value;
 }