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#include "fifo.h"
#include <assert.h>
#include <errno.h>
#define STARTING_SIZE 4096
void fifo_close(vfs_fd_t *fd) {
// TODO: Implement
(void)fd;
return;
}
void fifo_realloc(FIFO_FILE *file) {
file->buffer_len += 4096;
file->buffer = krealloc(file->buffer, file->buffer_len);
}
int fifo_object_write(u8 *buffer, u64 offset, u64 len, FIFO_FILE *file) {
(void)offset;
file->has_data = 1;
if (file->write_len + len >= file->buffer_len) {
file->can_write = 0;
fifo_realloc(file);
return -EAGAIN;
}
memcpy(file->buffer + file->write_len, buffer, len);
file->write_len += len;
return len;
}
int fifo_object_read(u8 *buffer, u64 offset, u64 len, FIFO_FILE *file) {
(void)offset;
if (file->write_len == 0) {
file->has_data = 0;
return -EAGAIN;
}
if (len == 0) {
return 0;
}
file->can_write = 1;
if (len > file->write_len) {
len = file->write_len;
}
memcpy(buffer, file->buffer, len);
// Shift bufffer to the left
memcpy(file->buffer, file->buffer + len, file->buffer_len - len);
file->write_len -= len;
if (file->write_len == 0) {
file->has_data = 0;
}
return len;
}
FIFO_FILE *create_fifo_object(void) {
FIFO_FILE *n = kmalloc(sizeof(FIFO_FILE));
n->buffer = kmalloc(STARTING_SIZE);
n->buffer_len = STARTING_SIZE;
n->write_len = 0;
return n;
}
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