Add support for Raspberry Pi (and possibly similar boards)

README.md

@@ -40,6 +40,7 @@ Supported boards are:
 | `esp32dev`                                   | `espressif32` | `arduino`   | `serial` <br/> `wifi`            | `colcon.meta`            |
 | `nanorp2040connect`                          | `raspberrypi` | `arduino`   | `serial` <br/> `wifi_nina`       | `colcon_verylowmem.meta` |
 | `pico`                                       | `raspberrypi` | `arduino`   | `serial`                         | `colcon.meta`|
+| `raspberrypi_1b` <br/> `raspberrypi_2b` <br/> `raspberrypi_3b` <br/> `raspberrypi_zero` | `linux_arm` | `wiringpi` | `socket` | `linux.meta`|
 
 The community is encouraged to open pull request with custom use cases.
 
@@ -52,7 +53,7 @@ The community is encouraged to open pull request with custom use cases.
   ```bash
   apt install -y git cmake python3-pip
   ```
-  
+
 ### Platform specific requirements
 
 #### MacOS
@@ -132,6 +133,15 @@ The transport can be configured with the `board_microros_transport = <transport>
     set_microros_native_ethernet_transports(local_mac, local_ip, agent_ip, agent_port);
     ```
 
+  - `socket`
+
+    ```c
+    const char* agent_ip = "192.168.1.113";
+    uint16_t agent_port = 8888;
+
+    set_microros_socket_transports(agent_ip, agent_port);
+    ```
+
   - `custom`
 
     The user will need to write transport functions in app code and provide it to the micro-ROS library using [`rmw_uros_set_custom_transport()` API](https://micro.ros.org/docs/tutorials/advanced/create_custom_transports/)

extra_script.py

@@ -29,10 +29,16 @@
 main_path = os.path.realpath(".")
 global_env = DefaultEnvironment()
 board = env['BOARD']
-framework = env['PIOFRAMEWORK'][0]
+platform = env.get('PIOPLATFORM', None)
 extra_packages_path = "{}/extra_packages".format(env['PROJECT_DIR'])
 
-selected_board_meta = boards_metas[board] if board in boards_metas else "colcon.meta"
+if platform == 'linux_arm':
+    # Transports built for linux do not depend on the framework
+    framework = 'linux'
+    selected_board_meta = 'linux.meta'
+else:
+    framework = env['PIOFRAMEWORK'][0]
+    selected_board_meta = boards_metas[board] if board in boards_metas else "colcon.meta"
 
 # Retrieve the required transport. Default iron
 microros_distro = global_env.BoardConfig().get("microros_distro", "iron")
@@ -156,4 +162,4 @@ def update_env():
 if set(["clean_microros", "_idedata", "idedata"]).isdisjoint(set(COMMAND_LINE_TARGETS)):
     build_microros()
 
-update_env()
+update_env()

library.json

@@ -25,6 +25,6 @@
         "extraScript": "./extra_script.py"
     },
 
-    "frameworks": "arduino",
-    "platforms": "teensy, https://github.com/platformio/platform-espressif32.git#feature/arduino-upstream, atmelsam, raspberrypi, ststm32"
-}
+    "frameworks": "arduino, wiringpi",
+    "platforms": "teensy, https://github.com/platformio/platform-espressif32.git#feature/arduino-upstream, atmelsam, raspberrypi, ststm32, linux_arm"
+}

metas/linux.meta

@@ -0,0 +1,20 @@
+{
+    "names": {
+        "rcutils": {
+            "cmake-args": [
+                "-DCMAKE_C_FLAGS=-D_GNU_SOURCE"
+            ]
+        },
+        "rmw_microxrcedds": {
+            "cmake-args": [
+                "-DRMW_UXRCE_MAX_NODES=1",
+                "-DRMW_UXRCE_MAX_PUBLISHERS=10",
+                "-DRMW_UXRCE_MAX_SUBSCRIPTIONS=5",
+                "-DRMW_UXRCE_MAX_SERVICES=1",
+                "-DRMW_UXRCE_MAX_CLIENTS=1",
+                "-DRMW_UXRCE_MAX_HISTORY=4",
+                "-DRMW_UXRCE_TRANSPORT=custom"
+            ]
+        }
+    }
+}

platform_code/linux/socket/micro_ros_transport.cpp

@@ -0,0 +1,84 @@
+#include <micro_ros_platformio.h>
+
+#include <uxr/client/util/time.h>
+#include <uxr/client/profile/transport/custom/custom_transport.h>
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netdb.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <poll.h>
+#include <string>
+
+extern "C" {
+
+static int fd;
+
+bool platformio_transport_open(struct uxrCustomTransport * transport)
+{
+  const auto * locator = (const struct micro_ros_agent_locator *) transport->args;
+
+  struct addrinfo hints;
+
+  memset(&hints, 0, sizeof(hints));
+
+  hints.ai_family = AF_UNSPEC;
+  hints.ai_socktype = SOCK_DGRAM;
+  hints.ai_flags = AI_NUMERICSERV;
+  hints.ai_protocol = 0;
+
+  const auto port_s = std::to_string(locator->port);
+  struct addrinfo * p_addrs = nullptr;
+
+  if(getaddrinfo(locator->address, port_s.c_str(), &hints, &p_addrs) != 0)
+    return false;
+
+  struct addrinfo * p_addr;
+
+  for(p_addr = p_addrs; p_addr != nullptr; p_addr = p_addr->ai_next){
+    if(0 > (fd = socket(p_addr->ai_family, p_addr->ai_socktype, p_addr->ai_protocol)))
+      continue;
+
+    if(0 == connect(fd, p_addr->ai_addr, p_addr->ai_addrlen))
+      break;
+
+    close(fd);
+  }
+
+  freeaddrinfo(p_addrs);
+
+  return p_addr != nullptr;
+}
+
+bool platformio_transport_close(struct uxrCustomTransport * transport)
+{
+  close(fd);
+  return true;
+}
+
+size_t platformio_transport_write(struct uxrCustomTransport * transport, const uint8_t *buf, size_t len, uint8_t *)
+{
+  auto ret = send(fd, buf, len, 0);
+  return ret < 0 ? 0 : (size_t)ret;
+}
+
+size_t platformio_transport_read(struct uxrCustomTransport * transport, uint8_t *buf, size_t len, int timeout, uint8_t *)
+{
+  struct pollfd pfd;
+  int ret;
+
+  pfd.fd = fd;
+  pfd.events = POLLIN;
+  ret = poll(&pfd, 1, timeout);
+  switch(ret){
+    case -1:
+    case 0:
+      return 0;
+    default:
+      ret = recv(fd, buf, len, 0);
+      return ret < 0 ? 0 : (size_t)ret;
+  }
+}
+
+}

platform_code/linux/socket/micro_ros_transport.h

@@ -0,0 +1,21 @@
+#include <string.h>
+
+struct micro_ros_agent_locator {
+    char * address;
+    int port;
+};
+
+static inline void set_microros_socket_transports(const char * agent_address, uint16_t agent_port){
+    static struct micro_ros_agent_locator locator;
+    locator.address = strdup(agent_address);
+    locator.port = agent_port;
+
+    rmw_uros_set_custom_transport(
+        false,
+        (void *) &locator,
+        platformio_transport_open,
+        platformio_transport_close,
+        platformio_transport_write,
+        platformio_transport_read
+    );
+}