add --var option and watch mode structure

src/main.cpp

@@ -5,13 +5,17 @@
 #include <iostream>
 #include <libdwarf.h>
 #include <string>
+#include <sys/ptrace.h>
+#include <sys/user.h>
+#include <sys/wait.h>
 #include <unistd.h>
 
 int main(int argc, char **argv) {
   cxxopts::Options options("gwatch",
-                          "List global integer variables in a binary");
+                          "Watch global variable reads/writes in a binary");
-  options.add_options()("exec", "Executable to analyze",
+  options.add_options()("exec", "Executable to watch",
                         cxxopts::value<std::filesystem::path>())(
+      "var", "Variable name to watch", cxxopts::value<std::string>())(
       "h,help", "Print usage");
 
   auto result = options.parse(argc, argv);
@@ -22,6 +26,7 @@ int main(int argc, char **argv) {
   }
 
   auto exec_path = result["exec"].as<std::filesystem::path>();
+  bool watch_mode = result.count("var");
 
   // Open the binary file
   int fd = open(exec_path.c_str(), O_RDONLY);
@@ -44,9 +49,31 @@ int main(int argc, char **argv) {
     return 1;
   }
 
-  // List global integer variables
   Symbol symbol;
+
+  if (watch_mode) {
+    // Watch mode: find the variable and set up ptrace
+    auto var_name = result["var"].as<std::string>();
+    auto var_info = symbol.find_global_var(dbg, var_name);
+
+    if (!var_info) {
+      std::cerr << "Error: Variable '" << var_name << "' not found" << std::endl;
+      dwarf_finish(dbg);
+      close(fd);
+      return 1;
+    }
+
+    std::cout << "Watching variable: " << var_info->name << std::endl;
+    std::cout << "Address: 0x" << std::hex << var_info->address << std::dec << std::endl;
+    std::cout << "Size: " << var_info->size << " bytes" << std::endl;
+    std::cout << std::string(50, '-') << std::endl;
+
+    // TODO: Implement ptrace watchpoint
+    std::cerr << "Ptrace watchpoint not yet implemented" << std::endl;
+  } else {
+    // List mode: show all global integer variables
     symbol.list_global_integer_vars(dbg);
+  }
 
   // Cleanup
   dwarf_finish(dbg);