store state in .config/sunshine on Linux

sunshine/platform/linux/misc.cpp

@@ -0,0 +1,88 @@
+#include "sunshine/platform/common.h"
+
+#include <fstream>
+
+#include <arpa/inet.h>
+#include <ifaddrs.h>
+#include <pwd.h>
+#include <unistd.h>
+
+#include "sunshine/main.h"
+
+using namespace std::literals;
+namespace fs = std::filesystem;
+
+namespace platf {
+using ifaddr_t = util::safe_ptr<ifaddrs, freeifaddrs>;
+
+ifaddr_t get_ifaddrs() {
+  ifaddrs *p { nullptr };
+
+  getifaddrs(&p);
+
+  return ifaddr_t { p };
+}
+
+fs::path appdata() {
+  const char *homedir;
+  if((homedir = getenv("HOME")) == nullptr) {
+    homedir = getpwuid(geteuid())->pw_dir;
+  }
+
+  return fs::path { homedir } / ".config/sunshine"sv;
+}
+
+std::string from_sockaddr(const sockaddr *const ip_addr) {
+  char data[INET6_ADDRSTRLEN];
+
+  auto family = ip_addr->sa_family;
+  if(family == AF_INET6) {
+    inet_ntop(AF_INET6, &((sockaddr_in6 *)ip_addr)->sin6_addr, data,
+      INET6_ADDRSTRLEN);
+  }
+
+  if(family == AF_INET) {
+    inet_ntop(AF_INET, &((sockaddr_in *)ip_addr)->sin_addr, data,
+      INET_ADDRSTRLEN);
+  }
+
+  return std::string { data };
+}
+
+std::pair<std::uint16_t, std::string> from_sockaddr_ex(const sockaddr *const ip_addr) {
+  char data[INET6_ADDRSTRLEN];
+
+  auto family = ip_addr->sa_family;
+  std::uint16_t port;
+  if(family == AF_INET6) {
+    inet_ntop(AF_INET6, &((sockaddr_in6 *)ip_addr)->sin6_addr, data,
+      INET6_ADDRSTRLEN);
+    port = ((sockaddr_in6 *)ip_addr)->sin6_port;
+  }
+
+  if(family == AF_INET) {
+    inet_ntop(AF_INET, &((sockaddr_in *)ip_addr)->sin_addr, data,
+      INET_ADDRSTRLEN);
+    port = ((sockaddr_in *)ip_addr)->sin_port;
+  }
+
+  return { port, std::string { data } };
+}
+
+std::string get_mac_address(const std::string_view &address) {
+  auto ifaddrs = get_ifaddrs();
+  for(auto pos = ifaddrs.get(); pos != nullptr; pos = pos->ifa_next) {
+    if(pos->ifa_addr && address == from_sockaddr(pos->ifa_addr)) {
+      std::ifstream mac_file("/sys/class/net/"s + pos->ifa_name + "/address");
+      if(mac_file.good()) {
+        std::string mac_address;
+        std::getline(mac_file, mac_address);
+        return mac_address;
+      }
+    }
+  }
+
+  BOOST_LOG(warning) << "Unable to find MAC address for "sv << address;
+  return "00:00:00:00:00:00"s;
+}
+} // namespace platf