// ------------------------------- // // -------- Start of File -------- // // ------------------------------- // // ----------------------------------------------------------- // // C++ Source Code File Name: testprog.cpp // Compiler Used: MSVC40, egcs-2.90.29, HP CPP 10.24 // Produced By: Doug Gaer // File Creation Date: 03/25/2000 // Date Last Modified: 05/09/2000 // Copyright (c) 2000 Douglas M. Gaer // ----------------------------------------------------------- // // ------------- Program Description and Details ------------- // // ----------------------------------------------------------- // /* The VBD and VBS C++ classes are copyright (c) 1997 and 2000 by Douglas M. Gaer. All those who put this code or its derivatives in a commercial product MUST mention this copyright in their documentation for users of the products in which this code or its derivative classes are used. Otherwise, you have the freedom to redistribute verbatim copies of this source code, adapt it to your specific needs, or improve the code and release your improvements to the public provided that the modified files carry prominent notices stating that you changed the files and the date of any change. THIS SOFTWARE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. THE ENTIRE RISK OF THE QUALITY AND PERFORMANCE OF THIS SOFTWARE IS WITH YOU. SHOULD ANY ELEMENT OF THIS SOFTWARE PROVE DEFECTIVE, YOU WILL ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR, OR CORRECTION. Test program demonstrating the basic operation of the vbThread class using semaphores. */ // ----------------------------------------------------------- // #include <iostream.h> #include <stdlib.h> #include "vbthread.h" #include "vbsema.h" // Constants const int NUM_THREADS = 3; // Global semaphore object vbSemaphore sema; // Shared data int sharedData1 = 0; int sharedData2 = 0; // Class derived from the abstract vbThread base class class SimpleThread : public vbThread { public: SimpleThread() { } ~SimpleThread() { } private: // Base class interface void *ThreadEntryRoutine(vbThread_t *thread); }; void *SimpleThread::ThreadEntryRoutine(vbThread_t *thread) { cout << "Entering thread" << endl; if(sema.SemaphoreWait() != 0) { cout << sema.SemaphoreExceptionMessage() << endl; return ExitThread(thread, 1); } // ********** Critical Section ******************* // cout << "Start critical section, holding semaphore" << endl; // Access to shared data goes here ++sharedData1; --sharedData2; cout << "sharedData1 = " << sharedData1 << ", sharedData2 = " << sharedData2 << endl; cout << "End critical section, release semaphore" << endl; // ********** Critical Section ******************* // if(sema.SemaphorePost() != 0) { cout << sema.SemaphoreExceptionMessage() << endl; return ExitThread(thread, 1); } return 0; } int main(int argc, char **argv) { SimpleThread t; vbThread_t *thread[NUM_THREADS]; int i; cout << "Wait on semaphore to prevent access to shared data" << endl; cout << "sharedData1 = " << sharedData1 << ", sharedData2 = " << sharedData2 << endl; if(sema.SemaphoreWait() != 0) { cout << sema.SemaphoreExceptionMessage() << endl; return 0; } cout << "Creating " << NUM_THREADS << " threads" << endl; for(i = 0; i < NUM_THREADS; ++i) thread[i] = t.CreateThread(); cout << "Wait a bit until we are done with the shared data" << endl; t.sSleep(3); cout << "Unlock shared data" << endl; if(sema.SemaphorePost() != 0) { cout << sema.SemaphoreExceptionMessage() << endl; return 0; } cout << "Wait for the threads to complete, and release their resources" << endl; for(i = 0; i < NUM_THREADS; ++i) t.JoinThread(thread[i]); return 0; } // ----------------------------------------------------------- // // ------------------------------- // // --------- End of File --------- // // ------------------------------- //