bottleros/Kernel/utils/pipe.c

78 lines
1.5 KiB
C

#include "pipe.h"
int fds = 2;
node_t * firstPipe;
char openPipe(int fds[2] ,char * name) {
pipe_t * pipe = pvPortMalloc(sizeof(pipe_t));
strcpy(pipe->name, name);
if ((pipe->sem = semOpen(SEM_NAME, 1)) == NULL)
return EXIT_FAILURE;
pipe->fd[0] = fds++;
pipe->fd[1] = fds++;
fds[0] = pipe->fd[0];
fds[1] = pipe->fd[1];
return EXIT_SUCCESS;
}
void writePipe(int fd, char c) {
node_t * prev = NULL;
node_t * node = searchPipe(&prev, fd);
semWait(node->pipe->sem);
node->pipe->buffer[node->pipe->current++ % PIPE_MAX_SIZE] = c;
semPost(node->pipe->sem);
}
char readPipe(int fd) {
node_t * prev = NULL;
node_t * node = searchPipe(&prev, fd);
semWait(node->pipe->sem);
char c = node->pipe->buffer[node->pipe->current-- % PIPE_MAX_SIZE];
semPost(node->pipe->sem);
return c;
}
void closePipe(int fd) {
node_t * prev = NULL;
node_t * del = searchPipe(&prev, fd);
if (del == NULL)
return;
semWait(del->pipe->sem);
if (prev != NULL)
prev->next = del->next;
else firstPipe = del->next;
vPortFree(del->pipe);
vPortFree(del);
semPost(del->pipe->sem);
}
node_t * searchPipe(node_t ** previous, int fd) {
node_t * curr = firstPipe;
* previous = NULL;
while (curr != NULL) {
if (curr->pipe->fd == fd) {
break;
}
* previous = curr;
curr = curr->next;
}
if (curr == NULL) {
* previous = NULL;
return NULL;
}
return curr;
}