portable device access api based on unix file descriptors

bsp_linux/CMakeLists.txt

@@ -1 +1,3 @@
+add_subdirectory(hardware)
+
 target_sources(${TARGET_NAME} PRIVATE main.c)

bsp_linux/hardware/CMakeLists.txt

@@ -0,0 +1 @@
+target_sources(${TARGET_NAME} PRIVATE hardware.c)

bsp_linux/hardware/hardware.c

@@ -0,0 +1,28 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <sys/un.h>
+#include <unistd.h>
+
+#include <hardware/interfaces.h>
+
+extern const char *device_root;
+
+int hw_device_open(const char *path, size_t path_len) {
+  int sock;
+  if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
+    perror(NULL);
+    exit(-1);
+  }
+  struct sockaddr_un address;
+  address.sun_family = AF_UNIX;
+  snprintf(address.sun_path, sizeof(address.sun_path), "%s%.*s", device_root,
+           path_len, path);
+  if (connect(sock, (struct sockaddr *)&address, sizeof(address)) != 0) {
+    perror(NULL);
+    exit(-1);
+  }
+  return sock;
+}

bsp_linux/main.c

@@ -1,27 +1,52 @@
-#include <stdio.h>
+#include <errno.h>
+#include <getopt.h>
 #include <stdint.h>
+#include <stdio.h>
 #include <stdlib.h>
-
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
 #include <unistd.h>
 
+const char *device_root = "./";
+
 void mission(void);
 
-int get_descriptor_rw() {
-  return 1;
-}
+int get_descriptor_rw() { return 1; }
 
 void done() {
   printf("done.\n");
   exit(0);
 }
 
+int test_socket();
+
 // Don't ask me, it makes the linker happy and does not seem
 // to break anything ¯\_(ツ)_/¯
-void rust_eh_personality() {
-    puts("eh_personality");
-}
+void rust_eh_personality() { puts("eh_personality"); }
 
-int main(void) {
-    mission();
-    return 0;
+int main(int argc, char **argv) {
+  static struct option long_options[] = {
+      /*   NAME       ARGUMENT           FLAG  SHORTNAME */
+      {"device-root", required_argument, NULL, 'd'},
+      {"help", no_argument, NULL, 'h'},
+      {NULL, 0, NULL, 0}};
+  int c;
+  int option_index = 0;
+  while ((c = getopt_long(argc, argv, "hd:", long_options, &option_index)) !=
+         -1) {
+    switch (c) {
+    case 'd':
+      if (optarg != NULL) {
+        device_root = optarg;
+        break;
+      default:
+        fprintf(stderr, "Usage: %s -d device-root\n", argv[0]);
+        exit(EXIT_FAILURE);
+      }
+    }
+  }
+  
+  mission();
+  return 0;
 }