1 files changed, 94 insertions, 0 deletions
diff --git a/run/runner.cpp b/run/runner.cpp
new file mode 100644
index 0000000..8f19bfb
--- /dev/null
+++ b/run/runner.cpp
@@ -0,0 +1,94 @@
+
+#include <cstdio>
+#include <cerrno>
+#include <cstring>
+#include <cassert>
+#include <csignal>
+
+#include <iostream>
+
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <sys/mman.h>
+
+#include "common.hpp"
+#include "dos_emu.hpp"
+
+int loader_socket;
+
+enum ErrorCode {
+    ok,
+    socket_creation_failed,
+    connection_error
+};
+
+static ErrorCode connect_to_loader();
+static BinaryLoadMessage receive_message();
+static void load_binary(BinaryLoadMessage const& message);
+static void register_signal_handlers();
+
+int main(int, char*[]) {
+    if(connect_to_loader() != ok) {
+        return -1;
+    }
+    BinaryLoadMessage message = receive_message();
+    load_binary(message);
+    register_signal_handlers();
+
+    asm ("JMP *%0 \n\t"
+        :
+        : "r" (message.eip));
+}
+
+static ErrorCode connect_to_loader() {
+    if ((loader_socket = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) {
+        perror("socket");
+        return socket_creation_failed;
+    }
+
+    sockaddr_un addr;
+    addr.sun_family = AF_UNIX;
+    std::strncpy(addr.sun_path, socket_name.c_str(), sizeof addr.sun_path);
+
+    size_t len = strnlen(addr.sun_path, sizeof addr.sun_path) + sizeof(addr.sun_family);
+    if (connect(loader_socket, (struct sockaddr *)&addr, len) == -1) {
+        perror("connect");
+        return connection_error;
+    }
+    return ok;
+}
+
+static BinaryLoadMessage receive_message() {
+    BinaryLoadMessage message;
+    uint32_t bytes_received = recv(loader_socket, &message, sizeof message, 0);
+    assert((bytes_received == sizeof message) && "Didn't receive full BinaryLoadMessage");
+    return message;
+}
+
+static void load_binary(BinaryLoadMessage const& message) {
+    uint8_t* binary = static_cast<uint8_t*>(mmap((void*)message.base_address, message.binary_size - message.base_address, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0));
+    if(binary == MAP_FAILED) {
+        std::cerr << "error during mmap: " << errno << " " << strerror(errno) << std::endl;
+        exit(1);
+    }
+
+    assert((binary == (void*)message.base_address) && "binary couldn't be loaded on the prefered address.");
+
+    uint8_t x[message.base_address];
+    recv(loader_socket, x, sizeof(x), 0);
+
+    size_t bytes_received = recv(loader_socket, binary, message.binary_size - message.base_address, 0);
+
+    assert((bytes_received == message.binary_size - (size_t)message.base_address) && "bytes_received did not match expected");
+}
+
+static void register_signal_handlers() {
+    struct sigaction sa;
+
+    memset(&sa, 0, sizeof sa);
+    sigemptyset(&sa.sa_mask);
+    sa.sa_flags = SA_SIGINFO;
+    sa.sa_sigaction = dos_emu_handler;
+
+    sigaction(SIGSEGV, &sa, NULL);
+}