Enable shared memory && add pthread support (#282)

samples/multi-thread/wasm-apps/main.c

@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2019 Intel Corporation.  All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+ */
+
+#include <stdio.h>
+#include <pthread.h>
+
+static pthread_mutex_t mutex;
+static pthread_cond_t cond;
+
+static void *thread(void *arg)
+{
+    int *num = (int *)arg;
+
+    pthread_mutex_lock(&mutex);
+    printf("thread start \n");
+
+    for (int i = 0; i < 10; i++) {
+        *num = *num + 1;
+        printf("num: %d\n", *num);
+    }
+
+    pthread_cond_signal(&cond);
+    pthread_mutex_unlock(&mutex);
+
+    printf("thread exit \n");
+
+    return NULL;
+}
+
+int main(int argc, char *argv[])
+{
+    pthread_t tid;
+    int num = 0, ret = -1;
+
+    if (pthread_mutex_init(&mutex, NULL) != 0) {
+        printf("Failed to init mutex.\n");
+        return -1;
+    }
+    if (pthread_cond_init(&cond, NULL) != 0) {
+        printf("Failed to init cond.\n");
+        goto fail1;
+    }
+
+    pthread_mutex_lock(&mutex);
+    if (pthread_create(&tid, NULL, thread, &num) != 0) {
+        printf("Failed to create thread.\n");
+        goto fail2;
+    }
+
+    printf("cond wait start\n");
+    pthread_cond_wait(&cond, &mutex);
+    pthread_mutex_unlock(&mutex);
+    printf("cond wait success.\n");
+
+    if (pthread_join(tid, NULL) != 0) {
+        printf("Failed to join thread.\n");
+    }
+
+    ret = 0;
+
+fail2:
+    pthread_cond_destroy(&cond);
+fail1:
+    pthread_mutex_destroy(&mutex);
+
+    return ret;
+}