reference, declarationdefinition
definition → references, declarations, derived classes, virtual overrides
reference to multiple definitions → definitions
unreferenced
    1
    2
    3
    4
    5
    6
    7
    8
    9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
   77
   78
   79
   80
   81
   82
   83
   84
   85
   86
   87
   88
   89
   90
   91
   92
   93
   94
   95
   96
   97
   98
   99
  100
  101
  102
  103
  104
  105
  106
  107
  108
  109
  110
  111
  112
  113
  114
  115
  116
  117
  118
  119
  120
  121
  122
  123
  124
  125
  126
  127
  128
  129
  130
  131
  132
  133
  134
  135
//===-- main.cpp ------------------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

// C includes
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>

// C++ includes
#include <chrono>
#include <mutex>
#include <random>
#include <thread>

std::thread g_thread_1;
std::thread g_thread_2;
std::thread g_thread_3;
std::mutex g_mask_mutex;

enum MaskAction {
    eGet,
    eAssign,
    eClearBits
};

uint32_t mask_access (MaskAction action, uint32_t mask = 0);

uint32_t
mask_access (MaskAction action, uint32_t mask)
{
    static uint32_t g_mask = 0;

    std::lock_guard<std::mutex> lock(g_mask_mutex);
    switch (action)
    {
    case eGet:
        break;

    case eAssign:
        g_mask |= mask;
        break;

    case eClearBits:
        g_mask &= ~mask;
        break;
    }
    return g_mask;
}

void *
thread_func (void *arg)
{
    uint32_t thread_index = *((uint32_t *)arg);
    uint32_t thread_mask = (1u << (thread_index));
    printf ("%s (thread index = %u) startng...\n", __FUNCTION__, thread_index);

    std::default_random_engine generator;
    std::uniform_int_distribution<int> distribution(0, 3000000);

    while (mask_access(eGet) & thread_mask)
    {
        // random micro second sleep from zero to 3 seconds
        int usec = distribution(generator);

        printf ("%s (thread = %u) doing a usleep (%d)...\n", __FUNCTION__, thread_index, usec);
        std::chrono::microseconds duration(usec);
        std::this_thread::sleep_for(duration);
        printf ("%s (thread = %u) after usleep ...\n", __FUNCTION__, thread_index); // Set break point at this line.
    }
    printf ("%s (thread index = %u) exiting...\n", __FUNCTION__, thread_index);
    return NULL;
}


int main (int argc, char const *argv[])
{
    int err;
    void *thread_result = NULL;
    uint32_t thread_index_1 = 1;
    uint32_t thread_index_2 = 2;
    uint32_t thread_index_3 = 3;
    uint32_t thread_mask_1 = (1u << thread_index_1);
    uint32_t thread_mask_2 = (1u << thread_index_2);
    uint32_t thread_mask_3 = (1u << thread_index_3);

    // Make a mask that will keep all threads alive
    mask_access (eAssign, thread_mask_1 | thread_mask_2 | thread_mask_3); // And that line.

    // Create 3 threads
    g_thread_1 = std::thread(thread_func, (void*)&thread_index_1);
    g_thread_2 = std::thread(thread_func, (void*)&thread_index_2);
    g_thread_3 = std::thread(thread_func, (void*)&thread_index_3);

    char line[64];
    while (mask_access(eGet) != 0)
    {
        printf ("Enter thread index to kill or ENTER for all:\n");
        fflush (stdout);
        // Kill threads by index, or ENTER for all threads

        if (fgets (line, sizeof(line), stdin))
        {
            if (line[0] == '\n' || line[0] == '\r' || line[0] == '\0')
            {
                printf ("Exiting all threads...\n");
                break;
            }
            int32_t index = strtoul (line, NULL, 0);
            switch (index)
            {
                case 1: mask_access (eClearBits, thread_mask_1); break;
                case 2: mask_access (eClearBits, thread_mask_2); break;
                case 3: mask_access (eClearBits, thread_mask_3); break;
            }
            continue;
        }

        break;
    }

    // Clear all thread bits to they all exit
    mask_access (eClearBits, UINT32_MAX);

    // Join all of our threads
    g_thread_1.join();
    g_thread_2.join();
    g_thread_3.join();

    return 0;
}