完成了顺序存储栈和链式存储栈

Chapter11/ds/line/stack/list/llist.c

@@ -0,0 +1,130 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "llist.h"
+
+LLIST *llist_create(int initsize)
+{
+    LLIST *new;
+
+    new = malloc(sizeof(*new));   // !!! 不是sizeof(initsize),也不是new,是*new
+    if (NULL == new)
+        return NULL;
+
+    new->size      = initsize;
+    new->head.prev = &new->head;
+    new->head.next = &new->head;
+
+    return new;
+}
+
+int llist_insert(LLIST *ptr, const void *data, int mode)
+{
+    struct llist_node_st *newnode;
+
+    newnode = malloc(sizeof(*newnode) + ptr->size);   // -4
+    if (NULL == newnode)
+        return -1;
+
+    memcpy(newnode->data, data, ptr->size);
+
+    if (LLIST_FORWARD == mode)
+    {
+        newnode->prev = &ptr->head;
+        newnode->next = ptr->head.next;
+    }
+    else if (LLIST_BACKWARD == mode)
+    {
+        newnode->prev = ptr->head.prev;
+        newnode->next = &ptr->head;
+    }
+    else   // error
+    {
+        return -3;
+    }
+
+    // !!! 妙啊
+    newnode->next->prev = newnode;
+    newnode->prev->next = newnode;
+
+    return 0;
+}
+
+static struct llist_node_st *find_(LLIST *ptr, const void *key, llist_cmp *cmp)
+{
+    struct llist_node_st *cur;
+
+    for (cur = ptr->head.next; cur != &ptr->head; cur = cur->next)
+    {
+        if (0 == cmp(key, cur->data))
+            break;
+    }
+
+    return cur;   // 找不到的时候，返回的cur就是ptr，返回NULL
+}
+
+void *llist_find(LLIST *ptr, const void *key, llist_cmp *cmp)
+{
+    struct llist_node_st *node;
+    node = find_(ptr, key, cmp);
+    if (node == &ptr->head)
+        return NULL;
+
+    return node->data;
+}
+
+int llist_delete(LLIST *ptr, const void *key, llist_cmp *cmp)
+{
+    struct llist_node_st *node;
+
+    node = find_(ptr, key, cmp);
+    if (node == &ptr->head)
+        return -1;
+
+    // !!!
+    node->prev->next = node->next;
+    node->next->prev = node->prev;
+    free(node);
+    return 0;
+}
+
+int llist_fetch(LLIST *ptr, const void *key, llist_cmp *cmp, void *data)
+{
+    struct llist_node_st *node;
+
+    node = find_(ptr, key, cmp);
+    if (node == &ptr->head)
+        return -1;
+
+    node->next->prev = node->prev;
+    node->prev->next = node->next;
+
+    if (data != NULL)
+        memcpy(data, node->data, ptr->size);
+
+    free(node);
+
+    return 0;
+}
+
+void llist_travel(LLIST *ptr, llist_op *op)
+{
+    struct llist_node_st *cur;
+
+    for (cur = ptr->head.next; cur != &ptr->head; cur = cur->next)
+        op(cur->data);
+}
+
+void llist_destroy(LLIST *ptr)
+{
+    struct llist_node_st *cur, *next;
+
+    for (cur = ptr->head.next; cur != &ptr->head; cur = next)
+    {
+        next = cur->next;
+        free(cur);
+    }
+
+    free(ptr);
+}