For school I am working on a project that has 2 reading threads running and 1 writing thread that work around a shared buffer. This shared buffer is some sort of pointer based list that we programmed ourselves. To make it thread-safe I used to pthread_rw_locks and also some pthread_barriers. When i tried to run my code it crashed almost instantly and it gave me a segmentation fault. When using the gdb debugger it gave me the following message:
program received signal SIGSEGV, Segmentation fault.
__pthread_barrier_init (barrier=0x0, attr=0x0, count=2) at pthread_barrier_init.c:47
47 pthread_barrier_init.c: No such file or directory.
When compiling I included the -lpthread flag and I also made sure to include the pthread.h in every file where it was used. Any idea why my program can't find this c file?
EDIT
This is a snippet of the code that I use. (This is barely all code but it goes wrong in this part)
This is my code for the main loop
int main(int argc, char*argv[])
{
sbuffer_t* buffer;
sbuffer_init(&buffer);
return 0;
}
This is my code for the buffer
/**
* basic node for the buffer, these nodes are linked together to create the buffer
*/
typedef struct sbuffer_node {
struct sbuffer_node *next; /**< a pointer to the next node*/
sensor_data_t data; /**< a structure containing the data */
} sbuffer_node_t;
/**
* a structure to keep track of the buffer
*/
struct sbuffer {
sbuffer_node_t *head; /**< a pointer to the first node in the buffer */
sbuffer_node_t *tail; /**< a pointer to the last node in the buffer */
pthread_rwlock_t* lock;
pthread_barrier_t* barrierRead; //Barrier to indicate that both reader threads have succesfully read the sensor reading
pthread_barrier_t* barrierWrite; //Barrier to indicate that a sensor reading has been removed
pthread_mutex_t* FIFOlock;
int finished;
};
int sbuffer_init(sbuffer_t **buffer) {
(*buffer) = malloc(sizeof(sbuffer_t));
(*buffer)->lock=malloc(sizeof(pthread_rwlock_t));
if (*buffer == NULL) return SBUFFER_FAILURE;
pthread_rwlock_init((*buffer)->lock,NULL);
pthread_rwlock_wrlock((*buffer)->lock);
pthread_barrier_init((*buffer)->barrierRead, NULL, READER_THREADS);
pthread_barrier_init((*buffer)->barrierWrite, NULL, READER_THREADS);
pthread_mutex_init((*buffer)->FIFOlock, NULL);
(*buffer)->head = NULL;
(*buffer)->tail = NULL;
(*buffer)->finished = CONNMGR_NOT_FINISHED;
pthread_rwlock_unlock((*buffer)->lock);
return SBUFFER_SUCCESS;
}
