server_t *create_server(int port, const char *localSocketName, int localSocketMode, int flags) {
server_t *srv;
SAIN ssa;
int reuse, ss;
#ifdef HAVE_IPV6
struct sockaddr_in6 ssa6;
#endif
struct sockaddr_un lusa;
#ifdef RSERV_DEBUG
printf(" - create_server(port = %d, socket = %s, mode = %d, flags = 0x%x)\n", port, localSocketName ? localSocketName : "<NULL>", localSocketMode, flags);
#endif
initsocks();
if (localSocketName) {
#ifndef unix
RSEprintf("ERROR: Local sockets are not supported on non-unix systems.\n");
return 0;
#else
ss = FCF("open socket", socket(AF_LOCAL, SOCK_STREAM, 0));
memset(&lusa, 0, sizeof(lusa));
lusa.sun_family = AF_LOCAL;
if (strlen(localSocketName) > sizeof(lusa.sun_path) - 2) {
RSEprintf("ERROR: Local socket name is too long for this system.\n");
return 0;
}
strcpy(lusa.sun_path, localSocketName);
remove(localSocketName); /* remove existing if possible */
#endif
} else
#ifdef HAVE_IPV6
ss = FCF("open socket", socket((flags & SRV_IPV6) ? AF_INET6 : AF_INET, SOCK_STREAM, 0));
#else
ss = FCF("open socket", socket(AF_INET, SOCK_STREAM, 0));
#endif
srv = (server_t*) calloc(1, sizeof(server_t));
if (!srv) {
RSEprintf("ERROR: cannot allocate memory for server structure\n");
return 0;
}
srv->ss = ss;
srv->unix_socket = localSocketName ? 1 : 0;
srv->flags = flags;
srv->parent = 0;
reuse = 1; /* enable socket address reusage */
setsockopt(ss, SOL_SOCKET, SO_REUSEADDR, (const char*)&reuse, sizeof(reuse));
#ifdef unix
if (localSocketName) {
FCF("bind", bind(ss, (SA*) &lusa, sizeof(lusa)));
if (localSocketMode)
chmod(localSocketName, localSocketMode);
} else {
#endif
#ifdef HAVE_IPV6
if (flags & SRV_IPV6) {
memset(&ssa6, 0, sizeof(ssa6));
ssa6.sin6_family = AF_INET6;
ssa6.sin6_port = htons(port);
ssa6.sin6_addr = (flags & SRV_LOCAL) ? in6addr_loopback : in6addr_any;
FCF("bind", bind(ss, (struct sockaddr*) &ssa6, sizeof(ssa6)));
} else {
#endif
memset(&ssa, 0, sizeof(ssa));
ssa.sin_family = AF_INET;
ssa.sin_port = htons(port);
ssa.sin_addr.s_addr = htonl((flags & SRV_LOCAL) ? INADDR_LOOPBACK : INADDR_ANY);
FCF("bind", bind(ss, (struct sockaddr*) &ssa, sizeof(ssa)));
#ifdef HAVE_IPV6
} /* if (flags & SRV_IPV6) else */
#endif
#ifdef unix
} /* if (localSocketName) else */
#endif
add_active_srv_socket(ss);
FCF("listen", listen(ss, LISTENQ));
return srv;
}
void
SSPquad::GetStab(void)
// this function computes the stabilization stiffness matrix for the element
{
Vector g1(SSPQ_NUM_DIM);
Vector g2(SSPQ_NUM_DIM);
Matrix I(SSPQ_NUM_DIM,SSPQ_NUM_DIM);
Matrix FCF(SSPQ_NUM_DIM,SSPQ_NUM_DIM);
Matrix Jmat(SSPQ_NUM_DIM,SSPQ_NUM_DIM);
Matrix Jinv(SSPQ_NUM_DIM,SSPQ_NUM_DIM);
Matrix dNloc(SSPQ_NUM_NODE,SSPQ_NUM_DIM);
Matrix dN(SSPQ_NUM_NODE,SSPQ_NUM_DIM);
Matrix Mben(2,SSPQ_NUM_DOF);
double Hss;
double Hst;
double Htt;
// shape function derivatives (local crd) at center
dNloc(0,0) = -0.25;
dNloc(1,0) = 0.25;
dNloc(2,0) = 0.25;
dNloc(3,0) = -0.25;
dNloc(0,1) = -0.25;
dNloc(1,1) = -0.25;
dNloc(2,1) = 0.25;
dNloc(3,1) = 0.25;
// jacobian matrix
Jmat = mNodeCrd*dNloc;
// inverse of the jacobian matrix
Jmat.Invert(Jinv);
// shape function derivatives (global crd)
dN = dNloc*Jinv;
// define hourglass stabilization vector gamma = 0.25*(h - (h^x)*bx - (h^y)*by);
double hx = mNodeCrd(0,0) - mNodeCrd(0,1) + mNodeCrd(0,2) - mNodeCrd(0,3);
double hy = mNodeCrd(1,0) - mNodeCrd(1,1) + mNodeCrd(1,2) - mNodeCrd(1,3);
double gamma[4];
gamma[0] = 0.25*( 1.0 - hx*dN(0,0) - hy*dN(0,1));
gamma[1] = 0.25*(-1.0 - hx*dN(1,0) - hy*dN(1,1));
gamma[2] = 0.25*( 1.0 - hx*dN(2,0) - hy*dN(2,1));
gamma[3] = 0.25*(-1.0 - hx*dN(3,0) - hy*dN(3,1));
// define mapping matrices
Mmem.Zero();
Mben.Zero();
for (int i = 0; i < 4; i++) {
Mmem(0,2*i) = dN(i,0);
Mmem(1,2*i+1) = dN(i,1);
Mmem(2,2*i) = dN(i,1);
Mmem(2,2*i+1) = dN(i,0);
Mben(0,2*i) = gamma[i];
Mben(1,2*i+1) = gamma[i];
}
// base vectors
g1(0) = Jmat(0,0);
g1(1) = Jmat(1,0);
g2(0) = Jmat(0,1);
g2(1) = Jmat(1,1);
// normalize base vectors
g1.Normalize();
g2.Normalize();
// compute second moment of area tensor
double fourThree = 4.0/3.0;
I = fourThree*mThickness*J0*(DyadicProd(g1,g1) + DyadicProd(g2,g2));
// stabilization terms
Hss = (I(0,0)*Jinv(1,0)*Jinv(1,0) + I(0,1)*Jinv(0,0)*Jinv(1,0) + I(1,1)*Jinv(0,0)*Jinv(0,0))*0.25;
Htt = (I(0,0)*Jinv(1,1)*Jinv(1,1) + I(0,1)*Jinv(0,1)*Jinv(1,1) + I(1,1)*Jinv(0,1)*Jinv(0,1))*0.25;
Hst = (I(0,0)*Jinv(1,1)*Jinv(1,0) + I(0,1)*(Jinv(1,0)*Jinv(0,1) + Jinv(1,1)*Jinv(0,0)) + I(1,1)*Jinv(0,1)*Jinv(0,0))*0.25;
// get material tangent
const Matrix &CmatI = theMaterial->getInitialTangent();
// compute stabilization matrix
FCF(0,0) = (CmatI(0,0) - (CmatI(0,1) + CmatI(1,0)) + CmatI(1,1))*Hss;
FCF(0,1) = (CmatI(0,1) - (CmatI(0,0) + CmatI(1,1)) + CmatI(1,0))*Hst;
FCF(1,0) = (CmatI(1,0) - (CmatI(0,0) + CmatI(1,1)) + CmatI(0,1))*Hst;
FCF(1,1) = (CmatI(1,1) - (CmatI(0,1) + CmatI(1,0)) + CmatI(0,0))*Htt;
// compute stiffness matrix for stabilization terms
Kstab.Zero();
Kstab.addMatrixTripleProduct(1.0, Mben, FCF, 1.0);
return;
}
