From eb8870193715f61fbedea4e1ebb010c24147adec Mon Sep 17 00:00:00 2001
From: Gabriel Ionita <d9rect@pm.me>
Date: Sun, 26 Oct 2025 17:15:00 +0100
Subject: [PATCH] update command line parsing to require --var and support
 program arguments

---
 src/main.cpp | 64 ++++++++++++++++++++++++++++------------------------
 1 file changed, 34 insertions(+), 30 deletions(-)

diff --git a/src/main.cpp b/src/main.cpp
index 0ecae8d..2f804aa 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -7,6 +7,7 @@
 #include <libdwarf.h>
 #include <string>
 #include <unistd.h>
+#include <vector>
 
 int main(int argc, char **argv) {
   cxxopts::Options options("gwatch",
@@ -16,15 +17,31 @@ int main(int argc, char **argv) {
       "var", "Variable name to watch", cxxopts::value<std::string>())(
       "h,help", "Print usage");
 
+  options.allow_unrecognised_options();
+
   auto result = options.parse(argc, argv);
 
-  if (result.count("help") || argc < 2 || !result.count("exec")) {
+  if (result.count("help")) {
+    std::cout << "Usage: gwatch --var <symbol> --exec <path> [-- arg1 .. argN]" << std::endl;
     std::cout << options.help() << std::endl;
     return 0;
   }
 
+  if (!result.count("exec") || !result.count("var")) {
+    std::cerr << "Error: Both --exec and --var are required" << std::endl;
+    std::cerr << "Usage: gwatch --var <symbol> --exec <path> [-- arg1 .. argN]" << std::endl;
+    return 1;
+  }
+
   auto exec_path = result["exec"].as<std::filesystem::path>();
-  bool watch_mode = result.count("var");
+  auto var_name = result["var"].as<std::string>();
+
+  // Collect program arguments (after --)
+  std::vector<std::string> prog_args;
+  auto unmatched = result.unmatched();
+  for (const auto& arg : unmatched) {
+    prog_args.push_back(arg);
+  }
 
   // Open the binary file
   int fd = open(exec_path.c_str(), O_RDONLY);
@@ -47,42 +64,29 @@ int main(int argc, char **argv) {
     return 1;
   }
 
+  // Find the variable in debug info
   Symbol symbol;
+  auto var_info = symbol.find_global_var(dbg, var_name);
 
-  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;
-
-    // Close DWARF resources before forking
+  if (!var_info) {
+    std::cerr << "Error: Variable '" << var_name << "' not found" << std::endl;
     dwarf_finish(dbg);
     close(fd);
-
-    // Start watching the variable
-    Tracer tracer;
-    tracer.watch_variable(exec_path.string(), var_info->address, var_info->size);
-
-    return 0;
-  } else {
-    // List mode: show all global integer variables
-    symbol.list_global_integer_vars(dbg);
+    return 1;
   }
 
-  // Cleanup
+  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;
+
+  // Close DWARF resources before forking
   dwarf_finish(dbg);
   close(fd);
 
+  // Start watching the variable
+  Tracer tracer;
+  tracer.watch_variable(exec_path.string(), var_info->address, var_info->size, prog_args);
+
   return 0;
 }