#include #include #include #include /* now declare (and allocate space for) some kernel objects, like the two threads we will use */ cyg_thread thread_s[2]; /* space for two thread objects */ char stack[2][4096]; /* space for two 4K stacks */ /* now the handles for the threads */ cyg_handle_t simple_threadA, simple_threadB; /* and now variables for the procedure which is the thread */ cyg_thread_entry_t simple_program; /* and now a mutex to protect calls to the C library */ cyg_mutex_t cliblock; /* we install our own startup routine which sets up threads */ void cyg_user_start(void) { printf("Entering twothreads' cyg_user_start() function\n"); cyg_mutex_init(&cliblock); cyg_thread_create(4, simple_program, (cyg_addrword_t) 0, "Thread A", (void *) stack[0], 4096, &simple_threadA, &thread_s[0]); cyg_thread_create(4, simple_program, (cyg_addrword_t) 1, "Thread B", (void *) stack[1], 4096, &simple_threadB, &thread_s[1]); cyg_thread_resume(simple_threadA); cyg_thread_resume(simple_threadB); } /* this is a simple program which runs in a thread */ void simple_program(cyg_addrword_t data) { int message = (int) data; int delay; printf("Beginning execution; thread data is %d\n", message); cyg_thread_delay(200); for (;;) { delay = 200 + (rand() % 50); /* note: printf() must be protected by a call to cyg_mutex_lock() */ cyg_mutex_lock(&cliblock); { printf("Thread %d: and now a delay of %d clock ticks\n", message, delay); } cyg_mutex_unlock(&cliblock); cyg_thread_delay(delay); } }