fix: fix compile errors for Windows and WASM targets

src/jsonrpc-remote-machine.cpp

@@ -897,8 +897,7 @@ static json jsonrpc_machine_is_empty_handler(const json &j, const std::shared_pt
 /// \param j JSON request object
 /// \param session HTTP session
 /// \returns JSON response object
-static json jsonrpc_emancipate_handler(const json &j, const std::shared_ptr<http_session> &session) {
-    (void) session;
+static json jsonrpc_emancipate_handler(const json &j, const std::shared_ptr<http_session> & /*session*/) {
     jsonrpc_check_no_params(j);
     setpgid(0, 0);
     return jsonrpc_response_ok(j);

src/jsonrpc-virtual-machine.cpp

@@ -30,8 +30,12 @@
 #include <tuple>
 #include <utility>
 
+#include "os-features.h"
+
+#ifdef HAVE_FORK
 #include <sys/time.h>
 #include <unistd.h>
+#endif
 
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
@@ -363,6 +367,8 @@ jsonrpc_virtual_machine::jsonrpc_virtual_machine(std::string address) :
     check_server_version();
 }
 
+#ifdef HAVE_FORK
+
 static boost::asio::ip::tcp::endpoint address_to_endpoint(const std::string &address) {
     try {
         const auto pos = address.find_last_of(':');
@@ -426,9 +432,9 @@ jsonrpc_virtual_machine::jsonrpc_virtual_machine(const std::string &address, for
     if (grand_child == 0) { // grand-child and double-fork() succeeded
         sigprocmask(SIG_SETMASK, &omask, nullptr);
         char sigusr1[256] = "";
-        (void) snprintf(sigusr1, std::size(sigusr1), "--sigusr1=%d", ppid);
+        std::ignore = snprintf(sigusr1, std::size(sigusr1), "--sigusr1=%d", ppid);
         char server_fd[256] = "";
-        (void) snprintf(server_fd, std::size(server_fd), "--server-fd=%d", a.native_handle());
+        std::ignore = snprintf(server_fd, std::size(server_fd), "--server-fd=%d", a.native_handle());
         // NOLINTNEXTLINE(cppcoreguidelines-pro-type-const-cast)
         char *args[] = {const_cast<char *>(bin), server_fd, sigusr1, nullptr};
         if (execvp(bin, args) < 0) {
@@ -496,6 +502,14 @@ jsonrpc_virtual_machine::jsonrpc_virtual_machine(const std::string &address, for
     }
 }
 
+#else
+
+jsonrpc_virtual_machine::jsonrpc_virtual_machine(const std::string & /*address*/, fork_result & /*spawned*/) {
+    throw std::runtime_error{"fork() is unsupported in this platform"s};
+}
+
+#endif
+
 void jsonrpc_virtual_machine::do_load(const std::string &directory, const machine_runtime_config &runtime) {
     bool result = false;
     jsonrpc_request(m_ioc, m_stream, m_address, "machine.load", std::tie(directory, runtime), result, m_timeout);

src/os-features.h

@@ -68,4 +68,8 @@
 #define HAVE_USLEEP
 #endif
 
+#if !defined(NO_FORK) && (defined(__linux__) || defined(__unix__)) && !defined(__wasi__)
+#define HAVE_FORK
+#endif
+
 #endif

src/os.cpp

@@ -34,7 +34,6 @@
 #include "unique-c-ptr.h"
 
 #include <sys/time.h>
-#include <sys/wait.h>
 
 #ifdef HAVE_SIGACTION
 #include <csignal>
@@ -93,7 +92,11 @@
 #else // not _WIN32
 
 #if defined(HAVE_TTY) || defined(HAVE_MMAP) || defined(HAVE_TERMIOS) || defined(HAVE_USLEEP)
-#include <unistd.h> // write/read/close
+#include <unistd.h> // write/read/close/usleep/fork
+#endif
+
+#if defined(HAVE_FORK)
+#include <sys/wait.h> // waitpid
 #endif
 
 #if defined(HAVE_SELECT)
@@ -183,7 +186,7 @@ static void os_SIGWINCH_handler(int /*sig*/) {
 }
 #endif
 
-bool os_update_tty_size(tty_state *s) {
+bool os_update_tty_size([[maybe_unused]] tty_state *s) {
 #ifdef HAVE_TTY
 #if defined(HAVE_TERMIOS) && defined(HAVE_IOCTL)
     winsize ws{};
@@ -383,7 +386,7 @@ void os_prepare_tty_select([[maybe_unused]] select_fd_sets *fds) {
 #endif
 }
 
-bool os_poll_selected_tty(int select_ret, select_fd_sets *fds) {
+bool os_poll_selected_tty([[maybe_unused]] int select_ret, [[maybe_unused]] select_fd_sets *fds) {
     auto *s = get_state();
     if (!s->initialized) { // We can't poll when TTY is not initialized
         return false;
@@ -522,7 +525,7 @@ void os_putchars(const uint8_t *data, size_t len) {
     }
 }
 
-int os_mkdir(const char *path, int mode) {
+int os_mkdir(const char *path, [[maybe_unused]] int mode) {
 #ifdef HAVE_MKDIR
     return plat_mkdir(path, mode);
 #else
@@ -781,17 +784,20 @@ void os_sleep_us(uint64_t timeout_us) {
 #endif
 }
 
+#ifdef HAVE_FORK
 static void sig_alrm(int /*unused*/) {
     ;
 }
+#endif
 
 // this function forks and intermediate child, and the intermediate child forks a final child
 // the intermediate child simply exits immediately
 // the final child sends its pid to the parent via a pipe
 // the parent returns the final child pid
 // the final child returns 0
 // on error, the parent throws and the final child does not return
-int os_double_fork_or_throw(bool emancipate) {
+int os_double_fork_or_throw([[maybe_unused]] bool emancipate) {
+#ifdef HAVE_FORK
     int fd[2] = {-1, -1};
     struct sigaction chld_act {};
     bool restore_sigchld = false;
@@ -927,9 +933,15 @@ int os_double_fork_or_throw(bool emancipate) {
         }
         throw; // rethrow so caller can see why we failed
     }
+
+#else
+    throw std::runtime_error{"fork() is unsupported in this platform"s};
+
+#endif
 }
 
-int os_double_fork(bool emancipate, const char **err_msg) {
+int os_double_fork([[maybe_unused]] bool emancipate, [[maybe_unused]] const char **err_msg) {
+#ifdef HAVE_FORK
     static THREAD_LOCAL std::string error_storage;
     try {
         *err_msg = nullptr;
@@ -939,6 +951,11 @@ int os_double_fork(bool emancipate, const char **err_msg) {
         *err_msg = error_storage.c_str();
         return -1;
     }
+
+#else
+    *err_msg = "fork() is unsupported in this platform";
+
+#endif
 }
 
 } // namespace cartesi

src/virtio-net-carrier-slirp.cpp

@@ -185,7 +185,6 @@ virtio_net_carrier_slirp::virtio_net_carrier_slirp(const cartesi::virtio_net_use
     slirp_cfg.vhost.s_addr = htonl(SLIRP_DEFAULT_IPV4_VHOST);             // Host address/gateway
     slirp_cfg.vdhcp_start.s_addr = htonl(SLIRP_DEFAULT_IPV4_VDHCP_START); // DHCP start address
     slirp_cfg.vnameserver.s_addr = htonl(SLIRP_DEFAULT_IPV4_VNAMESERVER); // DNS server address
-    slirp_cfg.disable_dhcp = true;
     // ??(edubart): Should all the above settings be configurable by the user?
     // ??(edubart): Should we add support for IPv6? It is disabled by default.
     // Configure required slirp callbacks
@@ -195,8 +194,11 @@ virtio_net_carrier_slirp::virtio_net_carrier_slirp(const cartesi::virtio_net_use
     slirp_cbs.timer_new = slirp_timer_new;
     slirp_cbs.timer_free = slirp_timer_free;
     slirp_cbs.timer_mod = slirp_timer_mod;
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
     slirp_cbs.register_poll_fd = slirp_register_poll_fd;
     slirp_cbs.unregister_poll_fd = slirp_unregister_poll_fd;
+#pragma GCC diagnostic pop
     slirp_cbs.notify = slirp_notify;
 
     // Initialize slirp
@@ -292,7 +294,10 @@ void virtio_net_carrier_slirp::do_prepare_select(select_fd_sets *fds, uint64_t *
     slirp_select_fds slirp_fds{&fds->maxfd, readfds, writefds, exceptfds};
     const uint32_t initial_timeout_ms = *timeout_us / 1000;
     uint32_t timeout_ms = initial_timeout_ms;
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
     slirp_pollfds_fill(slirp, &timeout_ms, slirp_add_poll_cb, &slirp_fds);
+#pragma GCC diagnostic pop
     if (initial_timeout_ms != timeout_ms) {
         *timeout_us = static_cast<uint64_t>(timeout_ms) * 1000;
     }