doc: strcutures: use doxygen to reference functions

Use :c:func:`..` possible to reference and link doxygen documentation.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>

doc/reference/data_structures/dlist.rst

@@ -11,28 +11,28 @@ the head, tail or any internal node).  To do this, the list stores two
 pointers per node, and thus has somewhat higher runtime code and
 memory space needs.
 
-A ``sys_dlist_t`` struct may be instantiated by the user in any
+A :c:struct:`sys_dlist_t` struct may be instantiated by the user in any
-accessible memory.  It must be initialized with ``sys_dlist_init()``
+accessible memory.  It must be initialized with :c:func:`sys_dlist_init`
-or ``SYS_DLIST_STATIC_INIT()`` before use.  The ``sys_dnode_t`` struct
+or :c:macro:`SYS_DLIST_STATIC_INIT` before use.  The :c:struct:`sys_dnode_t` struct
 is expected to be provided by the user for any nodes addded to the
 list (typically embedded within the struct to be tracked, as described
 above).  It must be initialized in zeroed/bss memory or with
-``sys_dnode_init()`` before use.
+:c:func:`sys_dnode_init` before use.
 
 Primitive operations may retrieve the head/tail of a list and the
-next/prev pointers of a node with ``sys_dlist_peek_head()``,
+next/prev pointers of a node with :c:func:`sys_dlist_peek_head`,
-``sys_dlist_peek_tail()``, ``sys_dlist_peek_next()`` and
+:c:func:`sys_dlist_peek_tail`, :c:func:`sys_dlist_peek_next` and
-``sys_dlist_peek_prev()``.  These can all return NULL where
+:c:func:`sys_dlist_peek_prev`.  These can all return NULL where
 appropriate (i.e. for empty lists, or nodes at the endpoints of the
 list).
 
 A dlist can be modified in constant time by removing a node with
-``sys_dlist_remove()``, by adding a node to the head or tail of a list
+:c:func:`sys_dlist_remove`, by adding a node to the head or tail of a list
-with ``sys_dlist_prepend()`` and ``sys_dlist_append()``, or by
+with :c:func:`sys_dlist_prepend` and :c:func:`sys_dlist_append`, or by
-inserting a node before an existing node with ``sys_dlist_insert()``.
+inserting a node before an existing node with :c:func:`sys_dlist_insert`.
 
 As for slist, each node in a dlist can be processed in a natural code
-block style using ``SYS_DLIST_FOR_EACH_NODE()``.  This macro also
+block style using :c:macro:`SYS_DLIST_FOR_EACH_NODE`.  This macro also
 exists in a "FROM_NODE" form which allows for iterating from a known
 starting point, a "SAFE" variant that allows for removing the node
 being inspected within the code block, a "CONTAINER" style that
@@ -40,18 +40,18 @@ provides the pointer to a containing struct instead of the raw node,
 and a "CONTAINER_SAFE" variant that provides both properties.
 
 Convenience utilities provided by dlist include
-``sys_dlist_insert_at()``, which inserts a node that linearly searches
+:c:func:`sys_dlist_insert_at`, which inserts a node that linearly searches
 through a list to find the right insertion point, which is provided by
 the user as a C callback function pointer, and
-``sys_dlist_is_linked()``, which will affirmatively return whether or
+:c:func:`sys_dnode_is_linked`, which will affirmatively return whether or
 not a node is currently linked into a dlist or not (via an
 implementation that has zero overhead vs. the normal list processing).
 
 Double-linked List Internals
 ----------------------------
 
-Internally, the dlist implementation is minimal: the ``sys_dlist_t``
+Internally, the dlist implementation is minimal: the :c:struct:`sys_dlist_t`
-struct contains "head" and "tail" pointer fields, the ``sys_dnode_t``
+struct contains "head" and "tail" pointer fields, the :c:struct:`sys_dnode_t`
 contains "prev" and "next" pointers, and no other data is stored.  But
 in practice the two structs are internally identical, and the list
 struct is inserted as a node into the list itself.  This allows for a

doc/reference/data_structures/rbtree.rst

@@ -10,15 +10,15 @@ which has runtimes on search and removal operations bounded at
 O(log2(N)) for a tree of size N.  This is implemented using a
 conventional red/black tree as described by multiple academic sources.
 
-The ``struct rbtree`` tracking struct for a rbtree may be initialized
+The :c:struct:`rbtree` tracking struct for a rbtree may be initialized
 anywhere in user accessible memory.  It should contain only zero bits
 before first use.  No specific initialization API is needed or
 required.
 
 Unlike a list, where position is explicit, the ordering of nodes
 within an rbtree must be provided as a predicate function by the user.
-A function of type ``rb_lessthan_t()`` should be assigned to the
+A function of type :c:func:`rb_lessthan_t` should be assigned to the
-``lessthan_fn`` field of the ``struct rbtree`` before any tree
+``lessthan_fn`` field of the :c:struct`rbtree` struct before any tree
 operations are attempted.  This function should, as its name suggests,
 return a boolean True value if the first node argument is "less than"
 the second in the ordering desired by the tree.  Note that "equal" is
@@ -26,40 +26,40 @@ not allowed, nodes within a tree must have a single fixed order for
 the algorithm to work correctly.
 
 As with the slist and dlist containers, nodes within an rbtree are
-represented as a ``struct rbnode`` structure which exists in
+represented as a :c:struct:`rbnode` structure which exists in
 user-managed memory, typically embedded within the the data structure
 being tracked in the tree.  Unlike the list code, the data within an
 rbnode is entirely opaque.  It is not possible for the user to extract
 the binary tree topology and "manually" traverse the tree as it is for
 a list.
 
-Nodes can be inserted into a tree with ``rb_insert()`` and removed
+Nodes can be inserted into a tree with :c:func:`rb_insert` and removed
-with ``rb_remove()``.  Access to the "first" and "last" nodes within a
+with :c:func:`rb_remove`.  Access to the "first" and "last" nodes within a
 tree (in the sense of the order defined by the comparison function) is
-provided by ``rb_get_min()`` and ``rb_get_max()``.  There is also a
+provided by :c:func:`rb_get_min` and :c:func:`rb_get_max`.  There is also a
-predicate, ``rb_contains()``, which returns a boolean True if the
+predicate, :c:func:`rb_contains`, which returns a boolean True if the
 provided node pointer exists as an element within the tree.  As
 described above, all of these routines are guaranteed to have at most
 log time complexity in the size of the tree.
 
 There are two mechanisms provided for enumerating all elements in an
-rbtree.  The first, ``rb_walk()``, is a simple callback implementation
+rbtree.  The first, :c:func:`rb_walk`, is a simple callback implementation
 where the caller specifies a C function pointer and an untyped
 argument to be passed to it, and the tree code calls that function for
 each node in order.  This has the advantage of a very simple
 implementation, at the cost of a somewhat more cumbersome API for the
-user (not unlike ISO C's ``bsearch()`` routine).  It is a recursive
+user (not unlike ISO C's :c:func:`bsearch` routine).  It is a recursive
 implementation, however, and is thus not always available in
 environments that forbid the use of unbounded stack techniques like
 recursion.
 
-There is also a ``RB_FOR_EACH()`` iterator provided, which, like the
+There is also a :c:macro:`RB_FOR_EACH` iterator provided, which, like the
 similar APIs for the lists, works to iterate over a list in a more
 natural way, using a nested code block instead of a callback.  It is
 also nonrecursive, though it requires log-sized space on the stack by
 default (however, this can be configured to use a fixed/maximally size
 buffer instead where needed to avoid the dynamic allocation).  As with
-the lists, this is also available in a ``RB_FOR_EACH_CONTAINER()``
+the lists, this is also available in a :c:macro:`RB_FOR_EACH_CONTAINER`
 variant which enumerates using a pointer to a container field and not
 the raw node pointer.
 
@@ -94,12 +94,12 @@ modification.
 These rotations are conceptually implemented on top of a primitive
 that "swaps" the position of one node with another in the list.
 Typical implementations effect this by simply swapping the nodes
-internal "data" pointers, but because the Zephyr ``struct rbnode`` is
+internal "data" pointers, but because the Zephyr :c:struct:`rbnode` is
 intrusive, that cannot work.  Zephyr must include somewhat more
 elaborate code to handle the edge cases (for example, one swapped node
 can be the root, or the two may already be parent/child).
 
-The ``struct rbnode`` struct for a Zephyr rbtree contains only two
+The :c:struct:`rbnode` struct for a Zephyr rbtree contains only two
 pointers, representing the "left", and "right" children of a node
 within the binary tree.  Traversal of a tree for rebalancing following
 modification, however, routinely requires the ability to iterate

doc/reference/data_structures/ring_buffers.rst

@@ -52,62 +52,62 @@ data buffer to empty.
 
 
 A ``struct ring_buf`` may be placed anywhere in user-accessible
-memory, and must be initialized with ``ring_buf_init()`` before use.
+memory, and must be initialized with :c:func:`ring_buf_init` before use.
 This must be provided a region of user-controlled memory for use as
 the buffer itself.  Note carefully that the units of the size of the
 buffer passed change (either bytes or words) depending on how the ring
 buffer will be used later.  Macros for combining these steps in a
 single static declaration exist for convenience.
-``RING_BUF_DECLARE()`` will declare and statically initialize a ring
+:c:macro:`RING_BUF_DECLARE` will declare and statically initialize a ring
 buffer with a specified byte count, where
-``RING_BUF_ITEM_DECLARE_SIZE()`` will declare and statically
+:c:macro:`RING_BUF_ITEM_DECLARE_SIZE` will declare and statically
 initialize a buffer with a given count of 32 bit words.
-``RING_BUF_ITEM_DECLARE_POW2()`` can be used to initialize an
+:c:macro:`RING_BUF_ITEM_DECLARE_POW2` can be used to initialize an
 items-mode buffer with a memory region guaranteed to be a power of
 two, which enables various optimizations internal to the
 implementation.  No power-of-two initialization is available for
 bytes-mode ring buffers.
 
 "Bytes" data may be copied into the ring buffer using
-``ring_buf_put()``, passing a data pointer and byte count.  These
+:c:func:`ring_buf_put`, passing a data pointer and byte count.  These
 bytes will be copied into the buffer in order, as many as will fit in
 the allocated buffer.  The total number of bytes copied (which may be
-fewer than provided) will be returned.  Likewise ``ring_buf_get()``
+fewer than provided) will be returned.  Likewise :c:func:`ring_buf_get`
 will copy bytes out of the ring buffer in the order that they were
 written, into a user-provided buffer, returning the number of bytes
 that were transferred.
 
 To avoid multiply-copied-data situations, a "claim" API exists for
-byte mode.  ``ring_buf_put_claim()`` takes a byte size value from the
+byte mode.  :c:func:`ring_buf_put_claim` takes a byte size value from the
 user and returns a pointer to memory internal to the ring buffer that
 can be used to receive those bytes, along with a size of the
 contiguous internal region (which may be smaller than requested).  The
 user can then copy data into that region at a later time without
 assembling all the bytes in a single region first.  When complete,
-``ring_buf_put_finish()`` can be used to signal the buffer that the
+:c:func:`ring_buf_put_finish` can be used to signal the buffer that the
 transfer is complete, passing the number of bytes actually
 transferred.  At this point a new transfer can be initiated.
-Similarly, ``ring_buf_get_claim()`` returns a pointer to internal ring
+Similarly, :c:func:`ring_buf_get_claim` returns a pointer to internal ring
 buffer data from which the user can read without making a verbatim
-copy, and ``ring_buf_get_finish()`` signals the buffer with how many
+copy, and :c:func:`ring_buf_get_finish` signals the buffer with how many
 bytes have been consumed and allows for a new transfer to begin.
 
 "Items" mode works similarly to bytes mode, except that all transfers
 are in units of 32 bit words and all memory is assumed to be aligned
 on 32 bit boundaries.  The write and read operations are
-``ring_buf_item_put()`` and ``ring_buf_item_get()``, and work
+:c:func:`ring_buf_item_put` and :c:func:`ring_buf_item_get`, and work
 otherwise identically to the bytes mode APIs.  There no "claim" API
 provided for items mode.  One important difference is that unlike
-``ring_buf_put()``, ``ring_buf_item_put()`` will not do a partial
+:c:func:`ring_buf_put`, :c:func:`ring_buf_item_put` will not do a partial
 transfer; it will return an error in the case where the provided data
 does not fit in its entirety.
 
 The user can manage the capacity of a ring buffer without modifying it
-using the ``ring_buf_space_get()`` call (which returns a value of
+using the :c:func:`ring_buf_space_get` call (which returns a value of
 either bytes or items depending on how the ring buffer has been used),
-or by testing the ``ring_buf_is_empty()`` predicate.
+or by testing the :c:func:`ring_buf_is_empty` predicate.
 
-Finally, a ``ring_buf_reset()`` call exists to immediately empty a
+Finally, a :c:func:`ring_buf_reset` call exists to immediately empty a
 ring buffer, discarding the tracking of any bytes or items already
 written to the buffer.  It does not modify the memory contents of the
 buffer itself, however.

doc/reference/data_structures/slist.rst

@@ -3,7 +3,7 @@
 Single-linked List
 ==================
 
-Zephyr provides a ``sys_slist_t`` type for storing simple
+Zephyr provides a :c:struct:`sys_slist_t` type for storing simple
 singly-linked list data (i.e. data where each list element stores a
 pointer to the next element, but not the previous one).  This supports
 constant-time access to the first (head) and last (tail) elements of
@@ -12,53 +12,53 @@ constant time removal of the head.  Removal of subsequent nodes
 requires access to the "previous" pointer and thus can only be
 performed in linear time by searching the list.
 
-The ``sys_slist_t`` struct may be instantiated by the user in any
+The :c:struct:`sys_slist_t` struct may be instantiated by the user in any
 accessible memory.  It should be initialized with either
-``sys_slist_init()`` or by static assignment from SYS_SLIST_STATIC_INIT
+:c:func:`sys_slist_init` or by static assignment from SYS_SLIST_STATIC_INIT
 before use.  Its interior fields are opaque and should not be accessed
 by user code.
 
 The end nodes of a list may be retrieved with
-``sys_slist_peek_head()`` and ``sys_slist_peek_tail()``, which will
+:c:func:`sys_slist_peek_head` and :c:func:`sys_slist_peek_tail`, which will
 return NULL if the list is empty, otherwise a pointer to a
-``sys_snode_t`` struct.
+:c:struct:`sys_snode_t` struct.
 
-The ``sys_snode_t`` struct represents the data to be inserted.  In
+The :c:struct:`sys_snode_t` struct represents the data to be inserted.  In
 general, it is expected to be allocated/controlled by the user,
 usually embedded within a struct which is to be added to the list.
 The container struct pointer may be retrieved from a list node using
-``SYS_SLIST_CONTAINER()``, passing it the struct name of the
+:c:macro:`SYS_SLIST_CONTAINER`, passing it the struct name of the
 containing struct and the field name of the node.  Internally, the
-``sys_snode_t`` struct contains only a next pointer, which may be
+:c:struct:`sys_snode_t` struct contains only a next pointer, which may be
-accessed with ``sys_slist_peek_next()``.
+accessed with :c:func:`sys_slist_peek_next`.
 
 Lists may be modified by adding a single node at the head or tail with
-``sys_slist_prepend()`` and ``sys_slist_append()``.  They may also
+:c:func:`sys_slist_prepend` and :c:func:`sys_slist_append`.  They may also
-have a node added to an interior point with ``sys_slist_insert()``,
+have a node added to an interior point with :c:func:`sys_slist_insert`,
 which inserts a new node after an existing one.  Similarly
-``sys_slist_remove()`` will remove a node given a pointer to its
+:c:func:`sys_slist_remove` will remove a node given a pointer to its
 predecessor.  These operations are all constant time.
 
 Convenience routines exist for more complicated modifications to a
-list.  ``sys_slist_merge_slist()`` will append an entire list to an
+list.  :c:func:`sys_slist_merge_slist` will append an entire list to an
-existing one.  ``sys_slist_append_list()`` will append a bounded
+existing one.  :c:func:`sys_slist_append_list` will append a bounded
 subset of an existing list in constant time.  And
-``sys_slist_find_and_remove()`` will search a list (in linear time)
+:c:func:`sys_slist_find_and_remove` will search a list (in linear time)
 for a given node and remove it if present.
 
 Finally the slist implementation provides a set of "for each" macros
 that allows for iterating over a list in a natural way without needing
-to manually traverse the next pointers.  ``SYS_SLIST_FOR_EACH_NODE()``
+to manually traverse the next pointers.  :c:macro:`SYS_SLIST_FOR_EACH_NODE`
 will enumerate every node in a list given a local variable to store
-the node pointer.  ``SYS_SLIST_FOR_EACH_NODE_SAFE()`` behaves
+the node pointer.  :c:macro:`SYS_SLIST_FOR_EACH_NODE_SAFE` behaves
 similarly, but has a more complicated implementation that requires an
 extra scratch variable for storage and allows the user to delete the
 iterated node during the iteration.  Each of those macros also exists
-in a "container" variant (``SYS_SLIST_FOR_EACH_CONTAINER()`` and
+in a "container" variant (:c:macro:`SYS_SLIST_FOR_EACH_CONTAINER` and
-``SYS_SLIST_FOR_EACH_CONTAINER_SAFE()``) which assigns a local
+:c:macro:`SYS_SLIST_FOR_EACH_CONTAINER_SAFE`) which assigns a local
 variable of a type that matches the user's container struct and not
 the node struct, performing the required offsets internally.  And
-``SYS_SLIST_ITERATE_FROM_NODE()`` exists to allow for enumerating a
+:c:macro:`SYS_SLIST_ITERATE_FROM_NODE` exists to allow for enumerating a
 node and all its successors only, without inspecting the earlier part
 of the list.
 
@@ -66,8 +66,8 @@ Single-linked List Internals
 ----------------------------
 
 The slist code is designed to be minimal and conventional.
-Internally, a ``sys_slist_t`` struct is nothing more than a pair of
+Internally, a :c:struct:`sys_slist_t` struct is nothing more than a pair of
-"head" and "tail" pointer fields.  And a ``sys_snode_t`` stores only a
+"head" and "tail" pointer fields.  And a :c:struct:`sys_snode_t` stores only a
 single "next" pointer.
 
 .. figure:: slist.png
@@ -101,14 +101,14 @@ Only one such variant, sflist, exists in Zephyr at the moment.
 Flagged List
 ------------
 
-The ``sys_sflist_t`` is implemented using the described genlist
+The :c:struct:`sys_sflist_t` is implemented using the described genlist
 template API.  With the exception of symbol naming ("sflist" instead
 of "slist") and the additional API described next, it operates in all
 ways identically to the slist API.
 
 It adds the ability to associate exactly two bits of user defined
 "flags" with each list node.  These can be accessed and modified with
-``sys_sflist_flags_get()`` and ``sys_sflist_flags_get()``.
+:c:func:`sys_sfnode_flags_get` and :c:func:`sys_sfnode_flags_get`.
 Internally, the flags are stored unioned with the bottom bits of the
 next pointer and incur no SRAM storage overhead when compared with the
 simpler slist code.

include/sys/dlist.h

@@ -28,6 +28,12 @@
 extern "C" {
 #endif
 
+/**
+ * @defgroup doubly-linked-list_apis Doubly-linked list
+ * @ingroup datastructure_apis
+ * @{
+ */
+
 struct _dnode {
 	union {
 		struct _dnode *head; /* ptr to head of list (sys_dlist_t) */
@@ -42,11 +48,6 @@ struct _dnode {
 typedef struct _dnode sys_dlist_t;
 typedef struct _dnode sys_dnode_t;
 
- /**
-  * @defgroup doubly-linked-list_apis Doubly-linked list
-  * @ingroup datastructure_apis
-  * @{
-  */
 
 /**
  * @brief Provide the primitive to iterate on a list