Add AT chat library implementation

1 files changed, 124 insertions, 0 deletions

diff --git a/gatchat/ringbuffer.h b/gatchat/ringbuffer.h
new file mode 100644
index 00000000..b77c428b
--- /dev/null
+++ b/gatchat/ringbuffer.h
@@ -0,0 +1,124 @@
+/*
+ *
+ *  AT chat library with GLib integration
+ *
+ *  Copyright (C) 2008-2009  Intel Corporation. All rights reserved.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+#ifndef __GATCHAT_RINGBUFFER_H
+#define __GATCHAT_RINGBUFFER_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct ring_buffer {
+	unsigned char *buffer;
+	unsigned int size;
+	unsigned int in;
+	unsigned int out;
+};
+
+/*!
+ * Creates a new ring buffer with capacity size
+ */
+struct ring_buffer *ring_buffer_new(unsigned int size);
+
+/*!
+ * Frees the resources allocated for the ring buffer
+ */
+void ring_buffer_free(struct ring_buffer *buf);
+
+/*!
+ * Returns the capacity of the ring buffer
+ */
+int ring_buffer_capacity(struct ring_buffer *buf);
+
+/*!
+ * Resets the ring buffer, all data inside the buffer is lost
+ */
+void ring_buffer_reset(struct ring_buffer *buf);
+
+/*!
+ * Writes data of size len into the ring buffer buf.  Returns -1 if the
+ * write failed or the number of bytes written
+ */
+int ring_buffer_write(struct ring_buffer *buf, const void *data,
+			unsigned int len);
+
+/*!
+ * Advances the write counter by len, this is meant to be used with
+ * the ring_buffer_write_ptr function.  Returns the number of bytes
+ * actually advanced (the capacity of the buffer)
+ */
+int ring_buffer_write_advance(struct ring_buffer *buf, unsigned int len);
+
+/*!
+ * Returns the write pointer.  Careful not to write past the end of the
+ * buffer.  Use the ring_buffer_avail_no_wrap function,
+ * ring_buffer_write_advance.
+ */
+unsigned char *ring_buffer_write_ptr(struct ring_buffer *buf);
+
+/*!
+ * Returns the number of free bytes available in the buffer
+ */
+int ring_buffer_avail(struct ring_buffer *buf);
+
+/*!
+ * Returns the number of free bytes available in the buffer without wrapping
+ */
+int ring_buffer_avail_no_wrap(struct ring_buffer *buf);
+
+/*!
+ * Reads data from the ring buffer buf into memory region pointed to by data.
+ * A maximum of len bytes will be read.  Returns -1 if the read failed or
+ * the number of bytes read
+ */
+int ring_buffer_read(struct ring_buffer *buf, void *data,
+			unsigned int len);
+
+/*!
+ * Returns the read pointer with read offset specified by offset.  No bounds
+ * checking is performed.  Be careful not to read past the end of the buffer.
+ * Use the ring_buffer_len_no_wrap function, and ring_buffer_drain.
+ */
+unsigned char *ring_buffer_read_ptr(struct ring_buffer *buf,
+					unsigned int offset);
+
+/*!
+ * Returns the number of bytes currently available to be read in the buffer
+ */
+int ring_buffer_len(struct ring_buffer *buf);
+
+/*!
+ * Returns the number of bytes currently available to be read in the buffer
+ * without wrapping.
+ */
+int ring_buffer_len_no_wrap(struct ring_buffer *buf);
+
+/*!
+ * Drains the ring buffer of len bytes.  Returns the number of bytes the
+ * read counter was actually advanced.
+ */
+int ring_buffer_drain(struct ring_buffer *buf, unsigned int len);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __GATCHAT_RINGBUFFER_H */