Redis 5.0 RC3 (4.9.103) - Released Wed Jun 14 9:51:44 CEST 2018

1 files changed, 0 insertions, 164 deletions

diff --git a/rax.h b/rax.h
deleted file mode 100644
index 5b4d451..0000000
--- a/rax.h
+++ /dev/null
@@ -1,164 +0,0 @@
-#ifndef RAX_H
-#define RAX_H
-
-#include <stdint.h>
-
-/* Representation of a radix tree as implemented in this file, that contains
- * the strings "foo", "foobar" and "footer" after the insertion of each
- * word. When the node represents a key inside the radix tree, we write it
- * between [], otherwise it is written between ().
- *
- * This is the vanilla representation:
- *
- *              (f) ""
- *                \
- *                (o) "f"
- *                  \
- *                  (o) "fo"
- *                    \
- *                  [t   b] "foo"
- *                  /     \
- *         "foot" (e)     (a) "foob"
- *                /         \
- *      "foote" (r)         (r) "fooba"
- *              /             \
- *    "footer" []             [] "foobar"
- *
- * However, this implementation implements a very common optimization where
- * successive nodes having a single child are "compressed" into the node
- * itself as a string of characters, each representing a next-level child,
- * and only the link to the node representing the last character node is
- * provided inside the representation. So the above representation is turend
- * into:
- *
- *                  ["foo"] ""
- *                     |
- *                  [t   b] "foo"
- *                  /     \
- *        "foot" ("er")    ("ar") "foob"
- *                 /          \
- *       "footer" []          [] "foobar"
- *
- * However this optimization makes the implementation a bit more complex.
- * For instance if a key "first" is added in the above radix tree, a
- * "node splitting" operation is needed, since the "foo" prefix is no longer
- * composed of nodes having a single child one after the other. This is the
- * above tree and the resulting node splitting after this event happens:
- *
- *
- *                    (f) ""
- *                    /
- *                 (i o) "f"
- *                 /   \
- *    "firs"  ("rst")  (o) "fo"
- *              /        \
- *    "first" []       [t   b] "foo"
- *                     /     \
- *           "foot" ("er")    ("ar") "foob"
- *                    /          \
- *          "footer" []          [] "foobar"
- *
- * Similarly after deletion, if a new chain of nodes having a single child
- * is created (the chain must also not include nodes that represent keys),
- * it must be compressed back into a single node.
- *
- */
-
-#define RAX_NODE_MAX_SIZE ((1<<29)-1)
-typedef struct raxNode {
-    uint32_t iskey:1;     /* Does this node contain a key? */
-    uint32_t isnull:1;    /* Associated value is NULL (don't store it). */
-    uint32_t iscompr:1;   /* Node is compressed. */
-    uint32_t size:29;     /* Number of children, or compressed string len. */
-    /* Data layout is as follows:
-     *
-     * If node is not compressed we have 'size' bytes, one for each children
-     * character, and 'size' raxNode pointers, point to each child node.
-     * Note how the character is not stored in the children but in the
-     * edge of the parents:
-     *
-     * [header strlen=0][abc][a-ptr][b-ptr][c-ptr](value-ptr?)
-     *
-     * if node is compressed (strlen != 0) the node has 1 children.
-     * In that case the 'size' bytes of the string stored immediately at
-     * the start of the data section, represent a sequence of successive
-     * nodes linked one after the other, for which only the last one in
-     * the sequence is actually represented as a node, and pointed to by
-     * the current compressed node.
-     *
-     * [header strlen=3][xyz][z-ptr](value-ptr?)
-     *
-     * Both compressed and not compressed nodes can represent a key
-     * with associated data in the radix tree at any level (not just terminal
-     * nodes).
-     *
-     * If the node has an associated key (iskey=1) and is not NULL
-     * (isnull=0), then after the raxNode pointers poiting to the
-     * childen, an additional value pointer is present (as you can see
-     * in the representation above as "value-ptr" field).
-     */
-    unsigned char data[];
-} raxNode;
-
-typedef struct rax {
-    raxNode *head;
-    uint64_t numele;
-    uint64_t numnodes;
-} rax;
-
-/* Stack data structure used by raxLowWalk() in order to, optionally, return
- * a list of parent nodes to the caller. The nodes do not have a "parent"
- * field for space concerns, so we use the auxiliary stack when needed. */
-#define RAX_STACK_STATIC_ITEMS 32
-typedef struct raxStack {
-    void **stack; /* Points to static_items or an heap allocated array. */
-    size_t items, maxitems; /* Number of items contained and total space. */
-    /* Up to RAXSTACK_STACK_ITEMS items we avoid to allocate on the heap
-     * and use this static array of pointers instead. */
-    void *static_items[RAX_STACK_STATIC_ITEMS];
-    int oom; /* True if pushing into this stack failed for OOM at some point. */
-} raxStack;
-
-/* Radix tree iterator state is encapsulated into this data structure. */
-#define RAX_ITER_STATIC_LEN 128
-#define RAX_ITER_JUST_SEEKED (1<<0) /* Iterator was just seeked. Return current
-                                       element for the first iteration and
-                                       clear the flag. */
-#define RAX_ITER_EOF (1<<1)    /* End of iteration reached. */
-#define RAX_ITER_SAFE (1<<2)   /* Safe iterator, allows operations while
-                                  iterating. But it is slower. */
-typedef struct raxIterator {
-    int flags;
-    rax *rt;                /* Radix tree we are iterating. */
-    unsigned char *key;     /* The current string. */
-    void *data;             /* Data associated to this key. */
-    size_t key_len;         /* Current key length. */
-    size_t key_max;         /* Max key len the current key buffer can hold. */
-    unsigned char key_static_string[RAX_ITER_STATIC_LEN];
-    raxNode *node;          /* Current node. Only for unsafe iteration. */
-    raxStack stack;         /* Stack used for unsafe iteration. */
-} raxIterator;
-
-/* A special pointer returned for not found items. */
-extern void *raxNotFound;
-
-/* Exported API. */
-rax *raxNew(void);
-int raxInsert(rax *rax, unsigned char *s, size_t len, void *data, void **old);
-int raxTryInsert(rax *rax, unsigned char *s, size_t len, void *data, void **old);
-int raxRemove(rax *rax, unsigned char *s, size_t len, void **old);
-void *raxFind(rax *rax, unsigned char *s, size_t len);
-void raxFree(rax *rax);
-void raxFreeWithCallback(rax *rax, void (*free_callback)(void*));
-void raxStart(raxIterator *it, rax *rt);
-int raxSeek(raxIterator *it, const char *op, unsigned char *ele, size_t len);
-int raxNext(raxIterator *it);
-int raxPrev(raxIterator *it);
-int raxRandomWalk(raxIterator *it, size_t steps);
-int raxCompare(raxIterator *iter, const char *op, unsigned char *key, size_t key_len);
-void raxStop(raxIterator *it);
-int raxEOF(raxIterator *it);
-void raxShow(rax *rax);
-uint64_t raxSize(rax *rax);
-
-#endif