sys/io: Implement _pipe_read() and _pipe_write()

diff --git a/sys/io/pipe.c b/sys/io/pipe.c
index e3a6ab56e17836bc1f0edc0b095d9bcc1142a0d5..1749c52ee8b6a6f2f89adabca186d54a29d77d05 100644 (file)
--- a/sys/io/pipe.c
+++ b/sys/io/pipe.c
@@ -21,7 +21,7 @@ static struct file_ops _pipe_ops = {
 };
 
 struct pipe {
-       char data[PIPE_BUFSIZE];
+       char p_data[PIPE_BUFSIZE];
        size_t p_offset;
        size_t p_len;
 
@@ -30,24 +30,72 @@ struct pipe {
 
 static ssize_t _pipe_read(struct file *file, void *dst, const size_t dst_size)
 {
+       struct pipe *pipe;
        char buf[128];
+       ssize_t ret_val;
        int len;
 
        len = snprintf(buf, sizeof(buf), "%s(%p, %p, %lu)\n", __func__, file, dst, dst_size);
        debug(buf, len);
 
-       return(-ENOSYS);
+       ret_val = -EBADFD;
+        pipe = (struct pipe*)file_get_priv(file);
+
+       if(pipe) {
+               ret_val = pipe->p_len < dst_size ? pipe->p_len : dst_size;
+
+               if(ret_val > 0) {
+                       memcpy(dst, pipe->p_data + pipe->p_offset, ret_val);
+
+                       pipe->p_offset += ret_val;
+                       pipe->p_len -= ret_val;
+
+                       if(!pipe->p_len) {
+                               pipe->p_offset = 0;
+                       }
+               } else {
+                       ret_val = -EAGAIN;
+               }
+       }
+
+       return(ret_val);
 }
 
-static ssize_t _pipe_write(struct file *file, const void *src, const size_t src_size)
+static ssize_t _pipe_write(struct file *file, const void *src, const size_t src_len)
 {
+       struct pipe *pipe;
+       ssize_t ret_val;
        char buf[128];
        int len;
 
-       len = snprintf(buf, sizeof(buf), "%s(%p, %p, %lu)\n", __func__, file, src, src_size);
+       len = snprintf(buf, sizeof(buf), "%s(%p, %p, %lu)\n", __func__, file, src, src_len);
        debug(buf, len);
 
-       return(-ENOSYS);
+       ret_val = -EBADFD;
+       pipe = (struct pipe*)file_get_priv(file);
+
+       if(pipe) {
+               if(pipe->p_len && pipe->p_offset) {
+                       memcpy(pipe->p_data, pipe->p_data + pipe->p_offset, len);
+                       pipe->p_offset = 0;
+               }
+
+               ret_val = sizeof(pipe->p_data) - pipe->p_len;
+
+               if(src_len < ret_val) {
+                       ret_val = src_len;
+               }
+
+               if(ret_val > 0) {
+                       memcpy(pipe->p_data + pipe->p_len, src, ret_val);
+                       pipe->p_len += ret_val;
+               } else if(src_len > 0) {
+                       /* there wasn't enough space to write any data */
+                       ret_val = -EAGAIN;
+               }
+       }
+
+       return(ret_val);
 }
 
 int pipe_new(const int flags, struct file **dst)
@@ -134,7 +182,8 @@ void sys_pipe(pid_t pid, struct cxio_pipe *req)
 
                fd[i] = err;
 
-               len = snprintf(buf, sizeof(buf), "%s: pipe[%d]=%d fd=%p file=%p\n", __func__, i, fd[i], fildes[i], file);
+               len = snprintf(buf, sizeof(buf), "%s: pipe[%d]=%d fd=%p file=%p\n",
+                              __func__, i, fd[i], fildes[i], file);
                debug(buf, len);
        }