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// -*- c++ -*-
//-----------------------------------------------------------------------
//
// Name: sighand_test.C
//
// Synopsis:
// % sighand_test
//
// Description: test program for following classes:
//
// o SigSet
// o SigAction
// o SigHandler
//
// o SIGINTHandler
// o SIGUSR1Handler
// o SIGCHLDHandler
// o SIGALRMHandler
//
//-----------------------------------------------------------------------
#include <iostream>
using namespace std;
#include <assert.h>
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>
#include <sys/types.h>
#if !defined (WIN32)
#include <sys/wait.h>
#include "assa/SigHandler.h"
#include "assa/Handlers.h"
#include "assa/Logger.h"
using namespace ASSA;
#endif // !win32
int main()
{
#if !defined (WIN32)
SigSet sigs;
Log::open_log_file ("sighand_test.log");
trace("sighand_test");
cout << endl << "testing SigSet class:\n" << "---------------------\n";
cout << "empty set ... ";
if (!sigs.empty()) cout << "pass\n"; else cout << "error\n";
cout << "fill set ... ";
if (!sigs.fill()) cout << "pass\n"; else cout << "error\n";
cout << "add to set ... ";
if (!sigs.add(9)) cout << "pass\n"; else cout << "error\n";
cout << "del from set ... ";
if (!sigs.del(9)) cout << "pass\n"; else cout << "error\n";
cout << "add sig=11 to set ... ";
if (!sigs.add(11)) cout << "pass\n"; else cout << "error\n";
cout << "test for sig=11 in set ...";
if (sigs.is_member(11)) cout << "pass\n"; else cout << "error\n";
cout << "test for prt to sigset_t ...";
sigset_t *internal;
internal = sigs;
cout << "pass" << endl << flush;
cout << "\ntesting SigHandler class:\n";
cout << "---------------------------\n";
// -- installing handlers ---
//
SigHandler sha; // signal dispatcher
SIGINTHandler intha; // various signal handlers
SIGUSR1Handler usr1ha;
SIGCHLDHandler chldha;
SIGALRMHandler alrmha;
DL((TRACE,"installing SIGINT\n"));
assert(sha.install(SIGINT, &intha) == 0);
DL((TRACE,"installing SIGUSR1\n"));
assert(sha.install(SIGUSR1, &usr1ha) == 0);
DL((TRACE,"installing SIGCHLD\n"));
assert(sha.install(SIGCHLD, &chldha) == 0);
SigAction cancelact; // cancel action
// flush stdout here before fork - otherwise child will have a copy
// of stdout buffer after fork and that output ends up on terminal
// twice - first time from child and second time - from parent.
//
cout << flush;
// running test:
// - can parent get all 5 SIGUSR1 sent by the child?
// - can parent get different signal?
pid_t chldpid;
if ( (chldpid = fork()) == -1) {
cerr << "error: fork() failed\n";
exit(1);
}
else if (chldpid == 0) { // child
pid_t prnt = getppid();
for (int i=0; i<5; i++) { // send SIGUSR1 five times
/*
* From R.Stevens, Ch 10.14, p.297
*
* "additional occurrences of the same signal are usually not
* queued. If the signal ocurs five times while its blocked,
* when we unblock the signal the signal-handling function
* for that signal will *usually* be invoked only one time."
*
* That is why here we need some delay between signals sent
* to parent.
*/
DL((TRACE,"send SIGUSR1 # %d\n",i));
sleep(2);
kill(prnt, SIGUSR1);
if (i == 3) {
// sending *different* signal
DL((TRACE,"send *DIFFERENT* SIGINT\n"));
kill(prnt, SIGINT);
}
}
exit(0);
}
// From Linux sleep(3) manual:
//
// "sleep() may be implemented using SIGALRM;
// mixing calls to alarm() and sleep() is a bad idea."
//
// We can use select(2) instead:
struct timeval tv;
// parent waits for 5 signals of SIGUSR1, for one signal of SIGINT
// and also for the child to exit. If something goes wrong,
// then alarm kicks in and test continues.
DL((TRACE,"installing SIGALRM\n"));
assert(sha.install(SIGALRM, &alrmha, &cancelact) == 0);
alarm(20);
for (int finish = 0; !alrmha.alarmed(); ) {
DL((TRACE,"--------------next loop iteration------------\n"));
if (usr1ha.received_count() == 5) {
cout << "signal queueing test ... pass\n";
finish++;
usr1ha.resetState();
}
if (intha.graceful_quit()) {
cout << "*different* signal test ... pass\n";
finish++;
intha.resetState();
}
if (chldha.child_exited()) {
cout << "child exit signal test ... pass\n";
finish++;
chldha.resetState();
}
if (finish == 3)
break;
// sleep using select(2). After return from select(2), reset
// tv values.
tv.tv_sec = 5;
tv.tv_usec = 0;
DL((TRACE,"calling select\n"));
if (select(0,NULL,NULL,NULL, 0) != 0) {
if (errno != EINTR ) {
//
// we skip "Interrupted system call" (EINTR) here because
// we expect it to be interrupted by signals delivered by
// the child process
//
cout << "select(2) failed with errno - "
<< strerror (errno) << endl;
}
}
}
if (alrmha.alarmed())
cout << "\nsummary:\n\tsignal handler test ... failed\n";
else {
alarm(0); // turn off alarm
cout << "\nsummary:\n\tsignal handler test ... pass\n";
}
cout << "\nSigHandler test done!\n";
#endif // !win32
exit(0);
}
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