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//==========================================================================
//
//      tests/nc_test_slave.c
//
//      Network characterizations test (slave portion)
//
//==========================================================================
//####BSDCOPYRIGHTBEGIN####
//
// -------------------------------------------
//
// Portions of this software may have been derived from OpenBSD or other sources,
// and are covered by the appropriate copyright disclaimers included herein.
//
// -------------------------------------------
//
//####BSDCOPYRIGHTEND####
//==========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):    gthomas
// Contributors: gthomas
// Date:         2000-01-10
// Purpose:      
// Description:  
//              
//
//####DESCRIPTIONEND####
//
//==========================================================================
 
#include <cyg/hal/hal_arch.h>
#include <cyg/infra/diag.h>
#include <cyg/infra/testcase.h>
 
#include <pkgconf/net_lwip.h>
 
#include <lwip.h>
#include <lwip/sockets.h>
 
#ifdef CYGFUN_LWIP_MODE_SEQUENTIAL
#if LWIP_SOCKET
#if LWIP_TCP
#if LWIP_UDP
#if LWIP_COMPAT_SOCKETS
#if LWIP_POSIX_SOCKETS_IO_NAMES
#if 1 // SO_REUSE
 
 
#ifndef CYGPKG_LIBC_STDIO
#include <cyg/error/errno.h>
#define perror(s) diag_printf(#s ": %s\n", strerror(errno))
#else
#include <stdio.h>
#endif
 
#include "nc_test_framework.h"
 
 
#define STACK_SIZE               (CYGNUM_HAL_STACK_SIZE_TYPICAL + 0x1000)
#define MAX_LOAD_THREAD_LEVEL    20
#define MIN_LOAD_THREAD_LEVEL    0
#define NUM_LOAD_THREADS         10
#define CYGPKG_NET_THREAD_PRIORITY 7
#define IDLE_THREAD_PRIORITY     CYGPKG_NET_THREAD_PRIORITY+3
#define LOAD_THREAD_PRIORITY     CYGPKG_NET_THREAD_PRIORITY-1
#define MAIN_THREAD_PRIORITY     CYGPKG_NET_THREAD_PRIORITY-2
#define DESIRED_BACKGROUND_LOAD  20
 
static char         main_thread_stack[STACK_SIZE];
static char         idle_thread_stack[STACK_SIZE];
static cyg_thread   idle_thread_data;
static cyg_handle_t idle_thread_handle;
static cyg_sem_t    idle_thread_sem;
volatile static long long    idle_thread_count;
static cyg_tick_count_t idle_thread_start_time;
static cyg_tick_count_t idle_thread_stop_time;
static char         load_thread_stack[NUM_LOAD_THREADS][STACK_SIZE];
static cyg_thread   load_thread_data[NUM_LOAD_THREADS];
static cyg_handle_t load_thread_handle[NUM_LOAD_THREADS];
static cyg_sem_t    load_thread_sem[NUM_LOAD_THREADS];
static long         load_thread_level;
static void calibrate_load(int load);
static void start_load(int load);
static void do_some_random_computation(int p);
#define abs(n) ((n) < 0 ? -(n) : (n))
 
#define test_param_t cyg_addrword_t
#ifdef CYGDBG_NET_TIMING_STATS
extern void show_net_times(void);
#endif
 
#define MAX_BUF 8192
static unsigned char in_buf[MAX_BUF], out_buf[MAX_BUF];
 
extern void
cyg_test_exit(void);
 
static void
test_delay(int ticks)
{
    cyg_thread_delay(ticks);
}
 
 
void
pexit(char *s)
{
    perror(s);
#ifdef CYGDBG_NET_TIMING_STATS
    show_net_times();
#endif
    cyg_test_exit();
}
 
//
// Generic UDP test
//
 
static void
do_udp_test(int s1, struct nc_request *req, struct sockaddr_in *master)
{
    int i, s, td_len, seq, seq_errors, lost;
    struct sockaddr_in test_chan_slave, test_chan_master;
    fd_set fds;
    struct timeval timeout;
    struct nc_test_results results;
    struct nc_test_data *tdp;
    int nsent, nrecvd;
    int need_recv, need_send;
 
    need_recv = true;  need_send = true;
    switch (ntohl(req->type)) {
    case NC_REQUEST_UDP_SEND:
        need_recv = false;
        need_send = true;
        break;
    case NC_REQUEST_UDP_RECV:
        need_recv = true;
        need_send = false;
        break;
    case NC_REQUEST_UDP_ECHO:
        break;
    }
 
    s = socket(AF_INET, SOCK_DGRAM, 0);
    if (s < 0) {
        pexit("datagram socket");
    }
 
    memset((char *) &test_chan_slave, 0, sizeof(test_chan_slave));
    test_chan_slave.sin_family = AF_INET;
    test_chan_slave.sin_len = sizeof(test_chan_slave);
    test_chan_slave.sin_addr.s_addr = htonl(INADDR_ANY);
    test_chan_slave.sin_port = htons(ntohl(req->slave_port));
 
    if (bind(s, (struct sockaddr *) &test_chan_slave, sizeof(test_chan_slave)) < 0) {
        perror("bind");
        close(s);
    }
 
    memcpy(&test_chan_master, master, sizeof(*master));
    test_chan_master.sin_port = htons(ntohl(req->master_port));
    nsent = 0;  nrecvd = 0;  seq = 0;  seq_errors = 0;  lost = 0;
    for (i = 0;  i < ntohl(req->nbufs);  i++) {
        if (need_recv) {
            FD_ZERO(&fds);
            FD_SET(s, &fds);
            timeout.tv_sec = NC_TEST_TIMEOUT;
            timeout.tv_usec = 0;
            if (select(s+1, &fds, 0, 0, &timeout) <= 0) {
                test_printf("recvfrom timeout, expecting seq #%d\n", seq);            
                if (++lost > MAX_ERRORS) {
                    test_printf("... giving up\n");
                    break;
                }
            } else {
                nrecvd++;
                tdp = (struct nc_test_data *)in_buf;
                td_len = ntohl(req->buflen) + sizeof(struct nc_test_data);
                if (recvfrom(s, tdp, td_len, 0, 0, 0) < 0) {
                    perror("recvfrom");
                    close(s);
                    return;
                }
                if ((ntohl(tdp->key1) == NC_TEST_DATA_KEY1) &&
                    (ntohl(tdp->key2) == NC_TEST_DATA_KEY2)) {
                    if (ntohl(tdp->seq) != seq) {
                        test_printf("Packets out of sequence - recvd: %lu, expected: %d\n",
                                    ntohl(tdp->seq), seq);
                        seq = ntohl(tdp->seq);
                        seq_errors++;
                    }
                } else {
                    test_printf("Bad data packet - key: %lx/%lx, seq: %lu\n",
                                ntohl(tdp->key1), ntohl(tdp->key2),
                                ntohl(tdp->seq));
                }
            }
        }
        if (need_send) {
            int retries = 10;
            int  sent = false;
            int res;
 
            tdp = (struct nc_test_data *)out_buf;
            tdp->key1 = htonl(NC_TEST_DATA_KEY1);
            tdp->key2 = htonl(NC_TEST_DATA_KEY2);
            tdp->seq = htonl(seq);
            td_len = ntohl(req->buflen) + sizeof(struct nc_test_data);
            tdp->len = htonl(td_len);
            while (!sent && (--retries >= 0)) {
                res = sendto(s, tdp, td_len, 0, 
                             (struct sockaddr *)&test_chan_master, sizeof(test_chan_master));
                if (res > 0) {
                    sent = true;
                    break;
                }
                if (errno == ENOBUFS) {
                    // Saturated the system
                    test_delay(1);   // Time for 200 500 byte 10-baseT packets 
                } else {
                    // What else to do?
                    close(s);
                    return;
                }
            }
            if (sent) {
                nsent++;
            } else {
                perror("sendto");
            }
        }
        seq++;
    }
    results.key1 = htonl(NC_TEST_RESULT_KEY1);
    results.key2 = htonl(NC_TEST_RESULT_KEY2);
    results.seq = req->seq;
    results.nsent = htonl(nsent);
    results.nrecvd = htonl(nrecvd);
    if (sendto(s, &results, sizeof(results), 0, 
               (struct sockaddr *)&test_chan_master, sizeof(test_chan_master)) < 0) {
        perror("sendto results");
    }
    close(s);
}
 
//
// Read data from a stream, accounting for the fact that packet 'boundaries'
// are not preserved.  This can also timeout (which would probably wreck the
// data boundaries).
//
 
int
do_read(int fd, void *buf, int buflen)
{
    char *p = (char *)buf;
    int len = buflen;
    int res;
    while (len) {
        res = read(fd, p, len);
        if (res < 0) {
            perror("read");
        } else {
            len -= res;
            p += res;
            if (res == 0) {
                break;
            }
        }
    }
    return (buflen - len);
}
 
//
// Generic TCP test
//
 
static void
do_tcp_test(int s1, struct nc_request *req, struct sockaddr_in *master)
{
    int i, s, td_len, seq, seq_errors, lost, test_chan, res;
    struct sockaddr_in test_chan_slave, test_chan_master;
    socklen_t len;
    struct nc_test_results results;
    struct nc_test_data *tdp;
    int nsent, nrecvd;
    int need_recv, need_send;
    static int slave_tcp_port = -1;
 
    need_recv = true;  need_send = true;
    switch (ntohl(req->type)) {
    case NC_REQUEST_TCP_SEND:
        need_recv = false;
        need_send = true;
        break;
    case NC_REQUEST_TCP_RECV:
        need_recv = true;
        need_send = false;
        break;
    case NC_REQUEST_TCP_ECHO:
        break;
    }
 
    if (slave_tcp_port < 0) {
        s = socket(AF_INET, SOCK_STREAM, 0);
        if (s < 0) {
            pexit("datagram socket");
        }
#if SO_REUSE
        {
            int one = 1;
 
            if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one))) {
                perror("setsockopt SO_REUSEADDR");
                return;
            }
            if (setsockopt(s, SOL_SOCKET, SO_REUSEPORT, &one, sizeof(one))) {
                perror("setsockopt SO_REUSEPORT");
                return;
            }
        }
#endif
        memset((char *) &test_chan_slave, 0, sizeof(test_chan_slave));
        test_chan_slave.sin_family = AF_INET;
        test_chan_slave.sin_len = sizeof(test_chan_slave);
        test_chan_slave.sin_addr.s_addr = htonl(INADDR_ANY);
        test_chan_slave.sin_port = htons(ntohl(req->slave_port));
 
        if (bind(s, (struct sockaddr *) &test_chan_slave, sizeof(test_chan_slave)) < 0) {
            perror("bind");
            close(s);
        }
        listen(s, 128);
        slave_tcp_port = s;
    }
 
    s = slave_tcp_port;
    len = sizeof(test_chan_master);
    if ((test_chan = accept(s, (struct sockaddr *)&test_chan_master, &len)) < 0) {
        pexit("accept");
    }
    len = sizeof(test_chan_master);
    getpeername(test_chan, (struct sockaddr *)&test_chan_master, &len);
    test_printf("connection from %s.%d\n", inet_ntoa(test_chan_master.sin_addr), 
                ntohs(test_chan_master.sin_port));
 
    nsent = 0;  nrecvd = 0;  seq = 0;  seq_errors = 0;  lost = 0;
    for (i = 0;  i < ntohl(req->nbufs);  i++) {
        if (need_recv) {
            tdp = (struct nc_test_data *)in_buf;
            td_len = ntohl(req->buflen) + sizeof(struct nc_test_data);
            res = do_read(test_chan, tdp, td_len);
            if (res != td_len) {
                test_printf("recvfrom timeout, expecting seq #%d\n", seq);            
                if (++lost > MAX_ERRORS) {
                    test_printf("... giving up\n");
                    break;
                }
            } else {
                nrecvd++;
                if ((ntohl(tdp->key1) == NC_TEST_DATA_KEY1) &&
                    (ntohl(tdp->key2) == NC_TEST_DATA_KEY2)) {
                    if (ntohl(tdp->seq) != seq) {
                        test_printf("Packets out of sequence - recvd: %lu, expected: %d\n",
                                    ntohl(tdp->seq), seq);
                        seq = ntohl(tdp->seq);
                        seq_errors++;
                    }
                } else {
                    test_printf("Bad data packet - key: %lx/%lx, seq: %lu\n",
                                ntohl(tdp->key1), ntohl(tdp->key2),
                                ntohl(tdp->seq));
                }
            }
        }
        if (need_send) {
            tdp = (struct nc_test_data *)out_buf;
            tdp->key1 = htonl(NC_TEST_DATA_KEY1);
            tdp->key2 = htonl(NC_TEST_DATA_KEY2);
            tdp->seq = htonl(seq);
            td_len = ntohl(req->buflen) + sizeof(struct nc_test_data);
            tdp->len = htonl(td_len);
            if (write(test_chan, tdp, td_len) != td_len) {
                perror("write");
                if (errno == ENOBUFS) {
                    // Saturated the system
                    test_delay(25);
                } else {
                    // What else to do?
                    close(test_chan);
                    return;
                }
            } else {
                nsent++;
            }
        }
        seq++;
    }
    results.key1 = htonl(NC_TEST_RESULT_KEY1);
    results.key2 = htonl(NC_TEST_RESULT_KEY2);
    results.seq = req->seq;
    results.nsent = htonl(nsent);
    results.nrecvd = htonl(nrecvd);
    if (write(test_chan, &results, sizeof(results)) != sizeof(results)) {
        perror("write");
    }
    close(test_chan);
}
 
//
// Protocol driver for testing slave.
//
// This function is the main routine running here, handling requests sent from
// the master and providing various responses.
//
static void
nc_slave(test_param_t param)
{
    int s;
    struct sockaddr_in my_addr, master;
    socklen_t masterlen;
    struct nc_request req;
    struct nc_reply reply;
    int done = false;
 
    test_printf("Start test for eth%d\n", param);
 
    s = socket(AF_INET, SOCK_DGRAM, 0);
    if (s < 0) {
        pexit("datagram socket");
    }
 
    memset((char *) &my_addr, 0, sizeof(my_addr));
    my_addr.sin_family = AF_INET;
    my_addr.sin_len = sizeof(my_addr);
    my_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    my_addr.sin_port = htons(NC_SLAVE_PORT);
 
    if (bind(s, (struct sockaddr *) &my_addr, sizeof(my_addr)) < 0) {
        pexit("bind");
    }
 
    while (!done) {
        masterlen = sizeof(master);
        if (recvfrom(s, &req, sizeof(req), 0, (struct sockaddr *)&master, &masterlen) < 0) {
            pexit("recvfrom");
        }
        test_printf("Request %lu from %s:%d\n", ntohl(req.type), 
                    inet_ntoa(master.sin_addr), ntohs(master.sin_port));
        reply.response = htonl(NC_REPLY_ACK);
        reply.seq = req.seq;
        switch (ntohl(req.type)) {
        case NC_REQUEST_DISCONNECT:
            done = true;
            break;
        case NC_REQUEST_UDP_SEND:
            test_printf("UDP send - %lu buffers, %lu bytes\n", ntohl(req.nbufs), ntohl(req.buflen));
            break;
        case NC_REQUEST_UDP_RECV:
            test_printf("UDP recv - %lu buffers, %lu bytes\n", ntohl(req.nbufs), ntohl(req.buflen));
            break;
        case NC_REQUEST_UDP_ECHO:
            test_printf("UDP echo - %lu buffers, %lu bytes\n", ntohl(req.nbufs), ntohl(req.buflen));
            break;
        case NC_REQUEST_TCP_SEND:
            test_printf("TCP send - %lu buffers, %lu bytes\n", ntohl(req.nbufs), ntohl(req.buflen));
            break;
        case NC_REQUEST_TCP_RECV:
            test_printf("TCP recv - %lu buffers, %lu bytes\n", ntohl(req.nbufs), ntohl(req.buflen));
            break;
        case NC_REQUEST_TCP_ECHO:
            test_printf("TCP echo - %lu buffers, %lu bytes\n", ntohl(req.nbufs), ntohl(req.buflen));
            break;
        case NC_REQUEST_SET_LOAD:
            start_load(ntohl(req.nbufs));
            break;
        case NC_REQUEST_START_IDLE:
            test_printf("Start IDLE thread\n");
            idle_thread_count = 0;
            idle_thread_start_time = cyg_current_time();
            cyg_semaphore_post(&idle_thread_sem);
            break;
        case NC_REQUEST_STOP_IDLE:
            cyg_semaphore_wait(&idle_thread_sem);
            idle_thread_stop_time = cyg_current_time();
            test_printf("Stop IDLE thread\n");
            reply.misc.idle_results.elapsed_time = htonl(idle_thread_stop_time - idle_thread_start_time);
            reply.misc.idle_results.count[0] = htonl(idle_thread_count >> 32);
            reply.misc.idle_results.count[1] = htonl((long)idle_thread_count);
            break;
        default:
            test_printf("Unrecognized request: %lu\n", ntohl(req.type));
            reply.response = htonl(NC_REPLY_NAK);
            reply.reason = htonl(NC_REPLY_NAK_UNKNOWN_REQUEST);
            break;
        }
        if (sendto(s, &reply, sizeof(reply), 0, (struct sockaddr *)&master, masterlen) < 0) {
            pexit("sendto");
        }
        if (reply.response == ntohl(NC_REPLY_NAK)) {
            continue;
        }
        switch (ntohl(req.type)) {
        case NC_REQUEST_UDP_SEND:
        case NC_REQUEST_UDP_RECV:
        case NC_REQUEST_UDP_ECHO:
            do_udp_test(s, &req, &master);
            break;
        case NC_REQUEST_TCP_SEND:
        case NC_REQUEST_TCP_RECV:
        case NC_REQUEST_TCP_ECHO:
            do_tcp_test(s, &req, &master);
            break;
        case NC_REQUEST_START_IDLE:
        case NC_REQUEST_STOP_IDLE:
        case NC_REQUEST_SET_LOAD:
        default:
            break;
        }
    }
    close(s);
}
 
void
net_test(void *arg)
{
    test_param_t param = (test_param_t)arg;
//    int i;
    if (param == 0) {
        test_printf("Start Network Characterization - SLAVE\n");
        calibrate_load(DESIRED_BACKGROUND_LOAD);
    }
    nc_slave(param);
#ifdef CYGDBG_NET_TIMING_STATS
    show_net_times();
#endif
#if LWIP_STATS_DISPLAY 
    stats_display();
#endif    
    cyg_test_exit();
}
 
 
//
// This function is called to calibrate the "background load" which can be
// applied during testing.  It will be called before any commands from the
// host are managed.
//
static void
calibrate_load(int desired_load)
{
    long long no_load_idle, load_idle;
    int percent_load;
    int high, low;
 
    // Set limits
    high = MAX_LOAD_THREAD_LEVEL;
    low = MIN_LOAD_THREAD_LEVEL;
 
    // Compute the "no load" idle value
    idle_thread_count = 0;
    cyg_semaphore_post(&idle_thread_sem);  // Start idle thread
    cyg_thread_delay(1*100);               // Pause for one second
    cyg_semaphore_wait(&idle_thread_sem);  // Stop idle thread
    no_load_idle = idle_thread_count;
    test_printf("No load = %d\n", (int)idle_thread_count);
 
    // First ensure that the HIGH level is indeed higher
    while (true) {
        load_thread_level = high;
        start_load(desired_load);              // Start up a given load
        idle_thread_count = 0;
        cyg_semaphore_post(&idle_thread_sem);  // Start idle thread
        cyg_thread_delay(1*100);               // Pause for one second
        cyg_semaphore_wait(&idle_thread_sem);  // Stop idle thread
        load_idle = idle_thread_count;
        start_load(0);                         // Shut down background load
        percent_load = 100 - ((load_idle * 100) / no_load_idle);
        test_printf("High Load[%ld] = %d => %d%%\n", load_thread_level, 
                    (int)idle_thread_count, percent_load);
        if ( percent_load > desired_load )
            break; // HIGH level is indeed higher
        low = load_thread_level; // known to be lower
        high *= 2; // else double it and try again
    }
 
    // Now chop down to the level required
    while (true) {
        load_thread_level = (high + low) / 2;
        start_load(desired_load);              // Start up a given load
        idle_thread_count = 0;
        cyg_semaphore_post(&idle_thread_sem);  // Start idle thread
        cyg_thread_delay(1*100);               // Pause for one second
        cyg_semaphore_wait(&idle_thread_sem);  // Stop idle thread
        load_idle = idle_thread_count;
        start_load(0);                         // Shut down background load
        percent_load = 100 - ((load_idle * 100) / no_load_idle);
        test_printf("Load[%ld] = %d => %d%%\n", load_thread_level, 
                    (int)idle_thread_count, percent_load);
        if (((high-low) <= 1) || (abs(desired_load-percent_load) <= 2)) break;
        if (percent_load < desired_load) {
            low = load_thread_level;
        } else {            
            high = load_thread_level;
        }
    }
 
    // Now we are within a few percent of the target; scale the load
    // factor to get a better fit, and test it, print the answer.
    load_thread_level *= desired_load;
    load_thread_level /= percent_load;
    start_load(desired_load);              // Start up a given load
    idle_thread_count = 0;
    cyg_semaphore_post(&idle_thread_sem);  // Start idle thread
    cyg_thread_delay(1*100);               // Pause for one second
    cyg_semaphore_wait(&idle_thread_sem);  // Stop idle thread
    load_idle = idle_thread_count;
    start_load(0);                         // Shut down background load
    percent_load = 100 - ((load_idle * 100) / no_load_idle);
    test_printf("Final load[%ld] = %d => %d%%\n", load_thread_level, 
                (int)idle_thread_count, percent_load);
//    no_load_idle_count_1_second = no_load_idle;
}
 
//
// This function is called to set up a load level of 'load' percent (given
// as a whole number, e.g. start_load(20) would mean initiate a background
// load of 20%, leaving the cpu 80% idle).
//
static void
start_load(int load)
{
    static int prev_load = 0;
    int i;
    test_printf("Set background load = %d%%\n", load);
    if (load == 0) {
        if (prev_load == 0) return;  // Nothing out there to stop
        for (i = 0;  i < prev_load/10;  i++) {
            cyg_semaphore_wait(&load_thread_sem[i]);
        }
        prev_load = 0;
    } else {
        for (i = 0;  i < load/10;  i++) {
            cyg_semaphore_post(&load_thread_sem[i]);
        }
        prev_load = load;
    }
}
 
//
// These thread(s) do some amount of "background" computing.  This is used
// to simulate a given load level.  They need to be run at a higher priority 
// than the network code itself.
//
// Like the "idle" thread, they run as long as their "switch" (aka semaphore)
// is enabled.
//
void
net_load(cyg_addrword_t who)
{
    int i;
    while (true) {
        cyg_semaphore_wait(&load_thread_sem[who]);
        for (i = 0;  i < load_thread_level;  i++) {
            do_some_random_computation(i);
        }
        cyg_thread_delay(1);  // Wait until the next 'tick'
        cyg_semaphore_post(&load_thread_sem[who]);
    }
}
 
//
// Some arbitrary computation, designed to use up the CPU and cause associated
// cache "thrash" behaviour - part of background load modelling.
//
static void
do_some_random_computation(int p)
{
    // Just something that might be "hard"
    volatile double x;
    x = ((p * 10) * 3.14159) / 180.0;  // radians
}
 
//
// This thread does nothing but count.  It will be allowed to count
// as long as the semaphore is "free".  
//
void
net_idle(cyg_addrword_t param)
{
    while (true) {
        cyg_semaphore_wait(&idle_thread_sem);
        idle_thread_count++;
        cyg_semaphore_post(&idle_thread_sem);
    }
}
 
static char stack[STACK_SIZE];
static cyg_thread thread_data;
static cyg_handle_t thread_handle;
 
void
tmain(cyg_addrword_t p)
{
    cyg_lwip_sequential_init();
    cyg_lwip_thread_new("main", net_test, NULL, main_thread_stack, STACK_SIZE, MAIN_THREAD_PRIORITY);
}
 
externC void
cyg_start( void )
{
    int i;
 
    CYG_TEST_INIT();
 
    // Create the idle thread environment
    cyg_semaphore_init(&idle_thread_sem, 0);
    cyg_thread_create(IDLE_THREAD_PRIORITY,     // Priority
                      net_idle,                 // entry
                      0,                        // entry parameter
                      "Network idle",           // Name
                      &idle_thread_stack[0],    // Stack
                      STACK_SIZE,               // Size
                      &idle_thread_handle,      // Handle
                      &idle_thread_data         // Thread data structure
    );
    cyg_thread_resume(idle_thread_handle);      // Start it
 
    // Create the load threads and their environment(s)
    for (i = 0;  i < NUM_LOAD_THREADS; i++) {
        cyg_semaphore_init(&load_thread_sem[i], 0);
        cyg_thread_create(LOAD_THREAD_PRIORITY,     // Priority
                          net_load,                 // entry
                          i,                        // entry parameter
                          "Background load",        // Name
                          &load_thread_stack[i][0], // Stack
                          STACK_SIZE,               // Size
                          &load_thread_handle[i],   // Handle
                          &load_thread_data[i]      // Thread data structure
        );
        cyg_thread_resume(load_thread_handle[i]);   // Start it
    }
 
    // Create a main thread, so we can run the scheduler and have time 'pass'
    cyg_thread_create(10,                       // Priority
                      tmain,                    // entry
                      0,                        // entry parameter
                      "socket echo test",       // Name
                      &stack[0],                // Stack
                      STACK_SIZE,               // Size
                      &thread_handle,           // Handle
                      &thread_data              // Thread data structure
            );
    cyg_thread_resume(thread_handle);           // Start it
 
    cyg_scheduler_start();
 
    CYG_TEST_FAIL_FINISH("Not reached");
}
 
#else // SO_REUSE
#define N_A_MSG "SO_REUSE currently unavailable"
#endif // SO_REUSE
 
#else // LWIP_POSIX_SOCKETS_IO_NAMES
#define N_A_MSG "POSIX socket function names disabled"
#endif
 
#else // LWIP_COMPAT_SOCKETS
#define N_A_MSG "Compatible socket support disabled"
#endif // LWIP_COMPAT_SOCKETS
 
#else // LWIP_UDP
#define N_A_MSG "UDP support disabled"
#endif // LWIP_UDP
 
#else // LWIP_TCP
#define N_A_MSG "TCP support disabled"
#endif // LWIP_TCP
 
#else // LWIP_SOCKET
#define N_A_MSG "Socket support disabled"
#endif // LWIP_SOCKET
 
#else // CYGFUN_LWIP_MODE_SEQUENTIAL
#define N_A_MSG "Not configured in 'Sequential' mode"
#endif // CYGFUN_LWIP_MODE_SEQUENTIAL
 
#ifdef N_A_MSG
externC void
cyg_start( void )
{
    CYG_TEST_INIT();
    CYG_TEST_NA(N_A_MSG);
}
#endif // N_A_MSG