Accessing Native Maths Libraries 5

gistfile1.c

// implement fortran xerbla
#define XERBLA_F77 F77_FUNC(xerbla,XERBLA)

// global cache of the VM ptr
JavaVM *JVMcache;

// Called when the native library is loaded
#ifdef __cplusplus
extern "C"
#endif
// The JNI_OnLoad function is called when the native library is loaded
JNIEXPORT jint JNICALL JNI_OnLoad(JavaVM *jvm, void *reserved)
{
     JVMcache=jvm; // set the global JVM pointer cache to one OnLoad JVM
     JNIEnv *env=NULL;
     if ((*jvm)->GetEnv(jvm, (void **)&env, JNI_VERSION_1_2)) {
         return JNI_ERR; // JNI version not supported
     }
     return JNI_VERSION_1_2;
}

// Normally we'd use a Fortran XERBLA from linked BLAS, but this (often) has a STOP command in it so we override this on the basis that return is called following xerbla
// in this way the user has a chance to handle the failure and try again opposed to exit()
#ifdef __cplusplus
extern "C" 
#endif
void XERBLA_F77(char *  SRNAME, int * INFO)
{
  int i;
 char name[7]; //LAPACK/BLAS names are always 6 characters or less
 memset(name,' ',6);
 for(i=0;i < 6;i++){
    name[i]=SRNAME[i];
 }
 name[6]='\0';
 printf("Hitting XERBLA overload. Exception state = %d\n",*INFO);
 printf("Hit called from %s, on arg %d\n",name,*INFO);
 JNIEnv *envPtr; // local grab of env ptr for this thread
 (*JVMcache)->AttachCurrentThrea(dJVMcache, (void **)&envPtr, NULL); // attach this thread to the globally cache JVM
 // find exception class
 jclass Exception = NULL;
 Exception = (*envPtr)->FindClass(envPtr,"com/opengamma/maths/nativewrappers/exceptions/OGNativeMathsWrapperInvalidArgumentException"); // find class
 if(Exception==NULL)
 {
        printf("Cannot find exception class in XERBLA implementation in libOGXERBLAoverride file=__FILE__,line=__LINE__. Hard Exiting.\n");
        exit(USER_DEFINED_ERROR_CODE);
 }
 char msg[100];
 memset(msg,' ',100);
 sprintf(msg,"Native BLAS: XERBLA: Invalid argument at position %d in routine %s \n",*INFO,name);
 (*envPtr)->ThrowNew(envPtr,Exception,msg); 
 return;
}