udebug: add udebug library code

Copied and adapted from udebug.git

Signed-off-by: Felix Fietkau <nbd@nbd.name>

1 files changed, 72 insertions, 0 deletions

diff --git a/udebug-proto.h b/udebug-proto.h
new file mode 100644
index 0000000..916c5fa
--- /dev/null
+++ b/udebug-proto.h
@@ -0,0 +1,72 @@
+/*
+ * udebug - debug ring buffer library
+ *
+ * Copyright (C) 2023 Felix Fietkau <nbd@nbd.name>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+#ifndef __UDEBUG_PROTO_H
+#define __UDEBUG_PROTO_H
+
+#include "udebug.h"
+
+struct udebug_hdr {
+	uint32_t ring_size;
+	uint32_t data_size;
+
+	uint32_t format;
+	uint32_t sub_format;
+
+	uintptr_t flags[8 / sizeof(uintptr_t)];
+	uintptr_t notify;
+
+	uint32_t head_hi;
+	uint32_t head;
+	uint32_t data_head;
+	uint32_t data_used;
+};
+
+enum udebug_client_msg_type {
+	CL_MSG_RING_ADD,
+	CL_MSG_RING_REMOVE,
+	CL_MSG_RING_NOTIFY,
+	CL_MSG_GET_HANDLE,
+	CL_MSG_RING_GET,
+	CL_MSG_ERROR,
+};
+
+struct udebug_client_msg {
+	uint8_t type;
+	uint8_t _pad[3];
+	uint32_t id;
+	union {
+		struct {
+			uint32_t ring_size, data_size;
+		};
+		uint32_t notify_mask;
+	};
+} __attribute__((packed, aligned(4)));
+
+static inline struct udebug_ptr *
+udebug_ring_ptr(struct udebug_hdr *hdr, uint32_t idx)
+{
+	struct udebug_ptr *ring = (struct udebug_ptr *)&hdr[1];
+	return &ring[idx & (hdr->ring_size - 1)];
+}
+
+static inline void *udebug_buf_ptr(struct udebug_buf *buf, uint32_t ofs)
+{
+	return buf->data + (ofs & (buf->data_size - 1));
+}
+
+#endif