--- /dev/null
+#ifndef CEPH_LIBRADOSSTRIPER_H
+#define CEPH_LIBRADOSSTRIPER_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <string.h>
+
+#include "../rados/librados.h"
+
+#define LIBRADOSSTRIPER_VER_MAJOR 0
+#define LIBRADOSSTRIPER_VER_MINOR 0
+#define LIBRADOSSTRIPER_VER_EXTRA 0
+
+#define LIBRADOSSTRIPER_VERSION(maj, min, extra) ((maj << 16) + (min << 8) + extra)
+
+#define LIBRADOSSTRIPER_VERSION_CODE LIBRADOSSTRIPER_VERSION(LIBRADOSSTRIPER_VER_MAJOR, LIBRADOSSTRIPER_VER_MINOR, LIBRADOSSTRIPER_VER_EXTRA)
+
+/**
+ * @typedef rados_striper_t
+ *
+ * A handle for interacting with striped objects in a RADOS cluster.
+ */
+typedef void *rados_striper_t;
+
+/**
+ * @defgroup libradosstriper_h_init Setup and Teardown
+ * These are the first and last functions to that should be called
+ * when using libradosstriper.
+ *
+ * @{
+ */
+
+/**
+ * Creates a rados striper using the given io context
+ * Striper has initially default object layout.
+ * See rados_striper_set_object_layout_*() to change this
+ *
+ * @param ioctx the rados context to use
+ * @param striper where to store the rados striper
+ * @returns 0 on success, negative error code on failure
+ */
+ int rados_striper_create(rados_ioctx_t ioctx,
+ rados_striper_t *striper);
+
+/**
+ * Destroys a rados striper
+ *
+ * @param striper the striper to destroy
+ */
+void rados_striper_destroy(rados_striper_t striper);
+
+/**
+ * Sets the object layout's stripe unit of a rados striper for future objects.
+ * This layout will be used when new objects are created (by writing to them)
+ * Already existing objects will be opened with their own layout.
+ *
+ * @param striper the targetted striper
+ * @param stripe_unit the stripe_unit value of the new object layout
+ * @returns 0 on success, negative error code on failure
+ */
+int rados_striper_set_object_layout_stripe_unit(rados_striper_t striper,
+ unsigned int stripe_unit);
+
+/**
+ * Sets the object layout's stripe count of a rados striper for future objects.
+ * This layout will be used when new objects are created (by writing to them)
+ * Already existing objects will be opened with their own layout.
+ *
+ * @param striper the targetted striper
+ * @param stripe_count the stripe_count value of the new object layout
+ * @returns 0 on success, negative error code on failure
+ */
+int rados_striper_set_object_layout_stripe_count(rados_striper_t striper,
+ unsigned int stripe_count);
+
+/**
+ * Sets the object layout's object_size of a rados striper for future objects.
+ * This layout will be used when new objects are created (by writing to them)
+ * Already existing objects will be opened with their own layout.
+ *
+ * @param striper the targetted striper
+ * @param object_size the object_size value of the new object layout
+ * @returns 0 on success, negative error code on failure
+ */
+int rados_striper_set_object_layout_object_size(rados_striper_t striper,
+ unsigned int object_size);
+
+/** @} init */
+
+/**
+ * @defgroup libradosstriper_h_synch_io Synchronous I/O
+ * Writes are striped to several rados objects which are then
+ * replicated to a number of OSDs based on the configuration
+ * of the pool they are in. These write functions block
+ * until data is in memory on all replicas of the object they're
+ * writing to - they are equivalent to doing the corresponding
+ * asynchronous write, and the calling
+ * rados_striper_ioctx_wait_for_complete().
+ *
+ * @{
+ */
+
+/**
+ * Synchronously write data to a striped object at the specified offset
+ *
+ * @param striper the striper in which the write will occur
+ * @param soid the name of the striped object
+ * @param buf data to write
+ * @param len length of the data, in bytes
+ * @param off byte offset in the object to begin writing at
+ * @returns 0 on success, negative error code on failure
+ * failure
+ */
+int rados_striper_write(rados_striper_t striper,
+ const char *soid,
+ const char *buf,
+ size_t len,
+ uint64_t off);
+
+/**
+ * Synchronously write an entire striped object
+ *
+ * The striped object is filled with the provided data. If the striped object exists,
+ * it is truncated and then written.
+ *
+ * @param striper the striper in which the write will occur
+ * @param soid the name of the striped object
+ * @param buf data to write
+ * @param len length of the data, in bytes
+ * @returns 0 on success, negative error code on failure
+ */
+int rados_striper_write_full(rados_striper_t striper,
+ const char *soid,
+ const char *buf,
+ size_t len);
+
+/**
+ * Append data to an object
+ *
+ * @param striper the striper in which the write will occur
+ * @param soid the name of the striped object
+ * @param buf the data to append
+ * @param len length of buf (in bytes)
+ * @returns 0 on success, negative error code on failure
+ * failure
+ */
+int rados_striper_append(rados_striper_t striper,
+ const char *soid,
+ const char *buf,
+ size_t len);
+
+/**
+ * Synchronously read data from a striped object at the specified offset
+ *
+ * @param striper the striper in which the read will occur
+ * @param soid the name of the striped object
+ * @param buf where to store the results
+ * @param len the number of bytes to read
+ * @param off the offset to start reading from in the object
+ * @returns number of bytes read on success, negative error code on
+ * failure
+ */
+int rados_striper_read(rados_striper_t striper,
+ const char *soid,
+ char *buf,
+ size_t len,
+ uint64_t off);
+
+/**
+ * Synchronously removes a striped object
+ *
+ * @note There is no atomicity of the deletion and the striped
+ * object may be left incomplete if an error is returned (metadata
+ * all present, but some stripes missing)
+ * However, there is a atomicity of the metadata deletion and
+ * the deletion can not happen if any I/O is ongoing (it
+ * will return EBUSY). Identically, no I/O will be able to start
+ * during deletion (same EBUSY return code)
+ * @param striper the striper in which the remove will occur
+ * @param soid the name of the striped object
+ * @returns 0 on success, negative error code on failure
+ */
+int rados_striper_remove(rados_striper_t striper,
+ const char* soid);
+
+/**
+ * Resize an object
+ *
+ * If this enlarges the object, the new area is logically filled with
+ * zeroes. If this shrinks the object, the excess data is removed.
+ *
+ * @note the truncation is not fully atomic. The metadata part is,
+ * so the behavior will be atomic from user point of view when
+ * the object size is reduced. However, in case of failure, old data
+ * may stay around, hidden. They may reappear if the object size is
+ * later grown, instead of the expected 0s. When growing the
+ * object and in case of failure, the new 0 data may not be
+ * fully created. This can lead to ENOENT errors when
+ * writing/reading the missing parts.
+ * @note the truncation can not happen if any I/O is ongoing (it
+ * will return EBUSY). Identically, no I/O will be able to start
+ * during truncation (same EBUSY return code)
+ * @param io the rados context to use
+ * @param soid the name of the striped object
+ * @param size the new size of the object in bytes
+ * @returns 0 on success, negative error code on failure
+ */
+int rados_striper_trunc(rados_ioctx_t io, const char *soid, uint64_t size);
+
+/** @} Synchronous I/O */
+
+/**
+ * @defgroup libradosstriper_h_xattrs Xattrs
+ * Extended attributes are stored as extended attributes on the
+ * first rados regular object of the striped object.
+ * Thus, they have the same limitations as the underlying
+ * rados extended attributes.
+ *
+ * @{
+ */
+
+/**
+ * Get the value of an extended attribute on a striped object.
+ *
+ * @param striper the striper in which the getxattr will occur
+ * @param oid name of the striped object
+ * @param name which extended attribute to read
+ * @param buf where to store the result
+ * @param len size of buf in bytes
+ * @returns length of xattr value on success, negative error code on failure
+ */
+int rados_striper_getxattr(rados_striper_t striper,
+ const char *oid,
+ const char *name,
+ char *buf,
+ size_t len);
+
+/**
+ * Set an extended attribute on a striped object.
+ *
+ * @param striper the striper in which the setxattr will occur
+ * @param oid name of the object
+ * @param name which extended attribute to set
+ * @param buf what to store in the xattr
+ * @param len the number of bytes in buf
+ * @returns 0 on success, negative error code on failure
+ */
+int rados_striper_setxattr(rados_striper_t striper,
+ const char *oid,
+ const char *name,
+ const char *buf,
+ size_t len);
+
+/**
+ * Delete an extended attribute from a striped object.
+ *
+ * @param striper the striper in which the rmxattr will occur
+ * @param oid name of the object
+ * @param name which xattr to delete
+ * @returns 0 on success, negative error code on failure
+ */
+int rados_striper_rmxattr(rados_striper_t striper,
+ const char *oid,
+ const char *name);
+
+/**
+ * Start iterating over xattrs on a striped object.
+ *
+ * @post iter is a valid iterator
+ *
+ * @param striper the striper in which the getxattrs will occur
+ * @param oid name of the object
+ * @param iter where to store the iterator
+ * @returns 0 on success, negative error code on failure
+ */
+int rados_striper_getxattrs(rados_striper_t striper,
+ const char *oid,
+ rados_xattrs_iter_t *iter);
+
+/**
+ * Get the next xattr on the striped object
+ *
+ * @pre iter is a valid iterator
+ *
+ * @post name is the NULL-terminated name of the next xattr, and val
+ * contains the value of the xattr, which is of length len. If the end
+ * of the list has been reached, name and val are NULL, and len is 0.
+ *
+ * @param iter iterator to advance
+ * @param name where to store the name of the next xattr
+ * @param val where to store the value of the next xattr
+ * @param len the number of bytes in val
+ * @returns 0 on success, negative error code on failure
+ */
+int rados_striper_getxattrs_next(rados_xattrs_iter_t iter,
+ const char **name,
+ const char **val,
+ size_t *len);
+
+/**
+ * Close the xattr iterator.
+ *
+ * iter should not be used after this is called.
+ *
+ * @param iter the iterator to close
+ */
+void rados_striper_getxattrs_end(rados_xattrs_iter_t iter);
+
+/** @} Xattrs */
+
+/**
+ * Synchronously get object stats (size/mtime)
+ *
+ * @param striper the striper in which the stat will occur
+ * @param soid the id of the striped object
+ * @param psize where to store object size
+ * @param pmtime where to store modification time
+ * @returns 0 on success, negative error code on failure
+ */
+int rados_striper_stat(rados_striper_t striper,
+ const char* soid,
+ uint64_t *psize,
+ time_t *pmtime);
+
+/**
+ * @defgroup libradosstriper_h_asynch_io Asynchronous I/O
+ * Read and write to objects without blocking.
+ *
+ * @{
+ */
+
+/**
+ * @typedef rados_striper_multi_completion_t
+ * Represents the state of a set of asynchronous operations
+ * it contains the aggregated return value once the operations complete
+ * and can be used to block until all operations are complete and/or safe.
+ */
+typedef void *rados_striper_multi_completion_t;
+
+/**
+ * Constructs a multi completion to use with asynchronous operations
+ *
+ * The complete and safe callbacks correspond to operations being
+ * acked and committed, respectively. The callbacks are called in
+ * order of receipt, so the safe callback may be triggered before the
+ * complete callback, and vice versa. This is affected by journalling
+ * on the OSDs.
+ *
+ * @note Read operations only get a complete callback.
+ * @note BUG: this should check for ENOMEM instead of throwing an exception
+ *
+ * @param cb_arg application-defined data passed to the callback functions
+ * @param cb_complete the function to be called when the operation is
+ * in memory on all relpicas
+ * @param cb_safe the function to be called when the operation is on
+ * stable storage on all replicas
+ * @param pc where to store the completion
+ * @returns 0
+ */
+int rados_striper_multi_aio_create_completion(void *cb_arg,
+ rados_callback_t cb_complete,
+ rados_callback_t cb_safe,
+ rados_striper_multi_completion_t *pc);
+
+/**
+ * Block until all operation complete
+ *
+ * This means data is in memory on all replicas.
+ *
+ * @param c operations to wait for
+ * @returns 0
+ */
+void rados_striper_multi_aio_wait_for_complete(rados_striper_multi_completion_t c);
+
+/**
+ * Block until all operation are safe
+ *
+ * This means data is on stable storage on all replicas.
+ *
+ * @param c operations to wait for
+ * @returns 0
+ */
+void rados_striper_multi_aio_wait_for_safe(rados_striper_multi_completion_t c);
+
+/**
+ * Has a multi asynchronous operation completed?
+ *
+ * @warning This does not imply that the complete callback has
+ * finished
+ *
+ * @param c async operations to inspect
+ * @returns whether c is complete
+ */
+int rados_striper_multi_aio_is_complete(rados_striper_multi_completion_t c);
+
+/**
+ * Is a multi asynchronous operation safe?
+ *
+ * @warning This does not imply that the safe callback has
+ * finished
+ *
+ * @param c async operations to inspect
+ * @returns whether c is safe
+ */
+int rados_striper_multi_aio_is_safe(rados_striper_multi_completion_t c);
+
+/**
+ * Block until all operations complete and callback completes
+ *
+ * This means data is in memory on all replicas and can be read.
+ *
+ * @param c operations to wait for
+ * @returns 0
+ */
+void rados_striper_multi_aio_wait_for_complete_and_cb(rados_striper_multi_completion_t c);
+
+/**
+ * Block until all operations are safe and callback has completed
+ *
+ * This means data is on stable storage on all replicas.
+ *
+ * @param c operations to wait for
+ * @returns 0
+ */
+void rados_striper_multi_aio_wait_for_safe_and_cb(rados_striper_multi_completion_t c);
+
+/**
+ * Has a multi asynchronous operation and callback completed
+ *
+ * @param c async operations to inspect
+ * @returns whether c is complete
+ */
+int rados_striper_multi_aio_is_complete_and_cb(rados_striper_multi_completion_t c);
+
+/**
+ * Is a multi asynchronous operation safe and has the callback completed
+ *
+ * @param c async operations to inspect
+ * @returns whether c is safe
+ */
+int rados_striper_multi_aio_is_safe_and_cb(rados_striper_multi_completion_t c);
+
+/**
+ * Get the return value of a multi asychronous operation
+ *
+ * The return value is set when all operations are complete or safe,
+ * whichever comes first.
+ *
+ * @pre The operation is safe or complete
+ *
+ * @note BUG: complete callback may never be called when the safe
+ * message is received before the complete message
+ *
+ * @param c async operations to inspect
+ * @returns aggregated return value of the operations
+ */
+int rados_striper_multi_aio_get_return_value(rados_striper_multi_completion_t c);
+
+/**
+ * Release a multi asynchrnous IO completion
+ *
+ * Call this when you no longer need the completion. It may not be
+ * freed immediately if the operation is not acked and committed.
+ *
+ * @param c multi completion to release
+ */
+void rados_striper_multi_aio_release(rados_striper_multi_completion_t c);
+
+/**
+ * Asynchronously write data to a striped object at the specified offset
+ *
+ * The return value of the completion will be 0 on success, negative
+ * error code on failure.
+ *
+ * @param striper the striper in which the write will occur
+ * @param soid the name of the striped object
+ * @param completion what to do when the write is safe and complete
+ * @param buf data to write
+ * @param len length of the data, in bytes
+ * @param off byte offset in the object to begin writing at
+ * @returns 0 on success, negative error code on
+ * failure
+ */
+int rados_striper_aio_write(rados_striper_t striper,
+ const char *soid,
+ rados_completion_t completion,
+ const char *buf,
+ size_t len,
+ uint64_t off);
+
+/**
+ * Asynchronously appends data to a striped object
+ *
+ * The return value of the completion will be 0 on success, negative
+ * error code on failure.
+ *
+ * @param striper the striper in which the write will occur
+ * @param soid the name of the striped object
+ * @param completion what to do when the write is safe and complete
+ * @param buf data to write
+ * @param len length of the data, in bytes
+ * @returns 0 on success, negative error code on
+ * failure
+ */
+int rados_striper_aio_append(rados_striper_t striper,
+ const char *soid,
+ rados_completion_t completion,
+ const char *buf,
+ size_t len);
+
+/**
+ * Asynchronously fills and object with the provided data.
+ * If the object exists, it is truncated and then written.
+ *
+ * The return value of the completion will be 0 on success, negative
+ * error code on failure.
+ *
+ * @param striper the striper in which the write will occur
+ * @param soid the name of the striped object
+ * @param completion what to do when the write is safe and complete
+ * @param buf data to write
+ * @param len length of the data, in bytes
+ * @returns 0 on success, negative error code on
+ * failure
+ */
+int rados_striper_aio_write_full(rados_striper_t striper,
+ const char *soid,
+ rados_completion_t completion,
+ const char *buf,
+ size_t len);
+
+/**
+ * Asynchronously read data from a striped object at the specified offset
+ *
+ * The return value of the completion will be number of bytes read on
+ * success, negative error code on failure.
+ *
+ * @param striper the striper in which the read will occur
+ * @param soid the name of the striped object
+ * @param completion what to do when the read is safe and complete
+ * @param buf where to store the results
+ * @param len the number of bytes to read
+ * @param off the offset to start reading from in the object
+ * @returns 0 on success, negative error code on
+ * failure
+ */
+int rados_striper_aio_read(rados_striper_t striper,
+ const char *soid,
+ rados_completion_t completion,
+ char *buf,
+ const size_t len,
+ uint64_t off);
+
+/**
+ * Asynchronously removes a striped object
+ *
+ * @note There is no atomicity of the deletion and the striped
+ * object may be left incomplete if an error is returned (metadata
+ * all present, but some stripes missing)
+ * However, there is a atomicity of the metadata deletion and
+ * the deletion can not happen if any I/O is ongoing (it
+ * will return EBUSY). Identically, no I/O will be able to start
+ * during deletion (same EBUSY return code)
+ * @param striper the striper in which the remove will occur
+ * @param soid the name of the striped object
+ * @param completion what to do when the remove is safe and complete
+ * @returns 0 on success, negative error code on failure
+ */
+
+int rados_striper_aio_remove(rados_striper_t striper,
+ const char* soid,
+ rados_completion_t completion);
+
+/**
+ * Block until all pending writes in a striper are safe
+ *
+ * This is not equivalent to calling rados_striper_multi_aio_wait_for_safe() on all
+ * write completions, since this waits for the associated callbacks to
+ * complete as well.
+ *
+ * @param striper the striper in which the flush will occur
+ * @returns 0 on success, negative error code on failure
+*/
+void rados_striper_aio_flush(rados_striper_t striper);
+
+/**
+ * Asynchronously get object stats (size/mtime)
+ *
+ * @param striper the striper in which the stat will occur
+ * @param soid the id of the striped object
+ * @param psize where to store object size
+ * @param pmtime where to store modification time
+ * @param completion what to do when the stats is complete
+ * @returns 0 on success, negative error code on failure
+ */
+int rados_striper_aio_stat(rados_striper_t striper,
+ const char* soid,
+ rados_completion_t completion,
+ uint64_t *psize,
+ time_t *pmtime);
+
+/** @} Asynchronous I/O */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
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