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#include <jni.h>
#include <jvmti.h>
#include <stdio.h>
#include <stdlib.h>
#include "getargssize.h"
JNIEXPORT jint JNICALL Java_getargssize_do_1getargssize_1tests
(JNIEnv *env, jclass klass)
{
JavaVM *vm;
jint err = env->GetJavaVM (&vm);
if (err < 0)
{
fprintf (stderr, "error getting VM\n");
exit (1);
}
jvmtiEnv *jvmti = NULL;
vm->GetEnv ((void **) &jvmti, JVMTI_VERSION_1_0);
if (jvmti == NULL)
{
fprintf (stderr, "error getting jvmti environment\n");
exit (1);
}
jint args_size;
jvmtiError jerr;
jmethodID meth_ids[4];
meth_ids[0] = env->GetMethodID (klass, "aMethod", "(FI)I");
meth_ids[1] = env->GetMethodID (klass, "bMethod", "(JDI)J");
meth_ids[2] = env->GetStaticMethodID (klass, "cMethod", "()Z");
meth_ids[3] = env->GetStaticMethodID (klass, "dMethod",
"(Ljava/lang/Object;)Ljava/lang/Object;");
for (int i = 0; i < 4; i++)
{
jerr = jvmti->GetArgumentsSize (meth_ids[i], &args_size);
if (jerr != JVMTI_ERROR_NONE)
{
char *error_name;
jvmti->GetErrorName (jerr, &error_name);
fprintf (stderr, "JVMTI Error: %s\n", error_name);
jvmti->Deallocate (reinterpret_cast<unsigned char *> (error_name));
}
else
{
printf ("Method %d requires %d slots for its arguments\n", i,
args_size);
}
}
return 0;
}
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