gabi/gwatch
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

update command line parsing to require --var and support program arguments

Browse Source
This commit is contained in:
Gabriel Ionita 2025-10-26 17:15:00 +01:00
parent 6129dee91d
commit eb88701937
Signed by: gabi
SSH Key Fingerprint: SHA256:mrbYmB/SGtDvT3etRoS6pDrMYWxR0/B5GSF6rR3qhhc
1 changed files with 34 additions and 30 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

64
src/main.cpp
View File

@ -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;
}