dyn.cpp

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/**
 * @file dyn.cpp
 *
 * @author Mara Bos <m-ou.se@m-ou.se>
 */

#include <dlfcn.h>

#include <px4_platform_common/module.h>
#include <px4_platform_common/log.h>

static void usage();

extern "C" {
    __EXPORT int dyn_main(int argc, char *argv[]);
}

static void usage()
{
    PRINT_MODULE_DESCRIPTION(
        R"(
### Description
Load and run a dynamic PX4 module, which was not compiled into the PX4 binary.

### Example
$ dyn ./hello.px4mod start

)");
    PRINT_MODULE_USAGE_NAME_SIMPLE("dyn", "command");
    PRINT_MODULE_USAGE_ARG("<file>", "File containing the module", false);
    PRINT_MODULE_USAGE_ARG("arguments...", "Arguments to the module", true);
}

int dyn_main(int argc, char *argv[]) {
    if (argc < 2) {
        usage();
        return 1;
    }

    void *handle = dlopen(argv[1], RTLD_NOW);

    if (!handle) {
        PX4_ERR("%s", dlerror());
        return 1;
    }

    void *main_address = dlsym(handle, "px4_module_main");

    if (!main_address) {
        PX4_ERR("%s", dlerror());
        dlclose(handle);
        return 1;
    }

    auto main_function = (int (*)(int, char **))main_address;

    return main_function(argc - 1, argv + 1);
}