我无法编译我的tldlist.c文件。
我如何解决这些问题：
请忽略未使用的变量/参数警告。我还没有实现一些方法。
注意：无法以任何方式修改tldlist.h。
编译器错误：
bash-3.2$ gcc -c -W -Wall tldlist.c
tldlist.c:86:21: warning: implicit declaration of function 'tldnode_create' is invalid in C99 [-Wimplicit-function-declaration]
TLDNode *node = tldnode_create(tld_name);
^
tldlist.c:86:14: warning: incompatible integer to pointer conversion initializing 'TLDNode *' (aka 'struct tldnode *') with an expression of
type 'int' [-Wint-conversion]
TLDNode *node = tldnode_create(tld_name);
^ ~~~~~~~~~~~~~~~~~~~~~~~~
tldlist.c:92:10: warning: implicit declaration of function 'tldlist_add_node' is invalid in C99 [-Wimplicit-function-declaration]
if (!tldlist_add_node(tld, tld_name, tld->root))
^
tldlist.c:71:7: warning: unused variable 'comparison' [-Wunused-variable]
int comparison;
^
tldlist.c:110:12: error: static declaration of 'tldlist_add_node' follows non-static declaration
static int tldlist_add_node(TLDList *tld, char *tld_name, TLDNode *node) {
^
tldlist.c:92:10: note: previous implicit declaration is here
if (!tldlist_add_node(tld, tld_name, tld->root))
^
tldlist.c:121:14: warning: incompatible integer to pointer conversion initializing 'TLDNode *' (aka 'struct tldnode *') with an expression of
type 'int' [-Wint-conversion]
TLDNode *new = tldnode_create(tld_name);
^ ~~~~~~~~~~~~~~~~~~~~~~~~
tldlist.c:128:14: warning: incompatible integer to pointer conversion initializing 'TLDNode *' (aka 'struct tldnode *') with an expression of
type 'int' [-Wint-conversion]
TLDNode *new = tldnode_create(tld_name);
^ ~~~~~~~~~~~~~~~~~~~~~~~~
tldlist.c:151:43: warning: unused parameter 'tld' [-Wunused-parameter]
TLDIterator *tldlist_iter_create(TLDList *tld) {
^
tldlist.c:159:41: warning: unused parameter 'iter' [-Wunused-parameter]
TLDNode *tldlist_iter_next(TLDIterator *iter) {
^
tldlist.c:174:10: error: conflicting types for 'tldnode_create'
TLDNode *tldnode_create(char *element) {
^
tldlist.c:86:21: note: previous implicit declaration is here
TLDNode *node = tldnode_create(tld_name);
^
8 warnings and 2 errors generated.
tldlist.c：
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "date.h"
#include "tldlist.h"
struct tldlist {
struct tldnode *root;
long count;
long size;
Date *begin;
Date *end;
};
/*
* TODO: check the definition of element.
*/
struct tldnode {
struct tldnode *parent;
struct tldnode *left;
struct tldnode *right;
char *element;
long count;
};
/*
* TODO: look at lecture slides
*/
struct tlditerator {
struct tldlist *tld;
};
/*
* tldlist_create generates a list structure for storing counts against
* top level domains (TLDs)
*
* creates a TLDList that is constrained to the `begin' and `end' Date's
* returns a pointer to the list if successful, NULL if not
*/
TLDList *tldlist_create(Date *begin, Date *end) {
TLDList *tldl = (TLDList *)malloc(sizeof(TLDList));
if (tldl != NULL) {
tldl->root = NULL;
tldl->count = 0;
tldl->begin = date_duplicate(begin);
tldl->end = date_duplicate(end);
}
return tldl;
};
/*
* tldlist_destroy destroys the list structure in `tld'
*
* all heap allocated storage associated with the list is returned to the heap
*/
void tldlist_destroy(TLDList *tld) {
if (tld != NULL)
free(tld);
};
/*
* tldlist_add adds the TLD contained in `hostname' to the tldlist if
* `d' falls in the begin and end dates associated with the list;
* returns 1 if the entry was counted, 0 if not
*/
int tldlist_add(TLDList *tld, char *hostname, Date *d) {
char *tld_capture;
char *tld_name;
int tld_length;
int comparison;
// check if 'd' in the date range
if (date_compare(tld->begin, d) > 0 || date_compare(tld->end, d) < 0)
return 0;
// get TLD from hostname
tld_capture = strrchr(hostname, '.') + 1;
tld_length = strlen(tld_capture);
tld_name = (char *)malloc(sizeof(char)*(tld_length+1));
tld_name[tld_length] = '\0';
strcpy(tld_name, tld_capture);
if (tld->root == NULL) {
/* insert at root */
TLDNode *node = tldnode_create(tld_name);
node->count++;
tld->root = node;
tld->size++;
} else {
/* add elsewhere */
if (!tldlist_add_node(tld, tld_name, tld->root))
free(tld_name);
else
tld->size++;
}
return 0;
};
/*
* insert the TLD to the tree
* consider 5 different cases:
* (1) TLD name < current and there is a left node
* (2) TLD name > current and there is a right node
* (3) TLD name < current and there is no left node
* (4) TLD name > current and there is no right node
* (5) TLD name is equal to current
*/
static int tldlist_add_node(TLDList *tld, char *tld_name, TLDNode *node) {
int comparison = strcmp(tld_name, node->element);
if ((comparison < 0) && (node->left != NULL))
/* case 1 */
return tldlist_add_node(tld, tld_name, node->left);
else if ((comparison > 0) && (node->right != NULL))
/* case 2 */
return tldlist_add_node(tld, tld_name, node->right);
else if ((comparison < 0) && (node->left == NULL)) {
/* case 3 */
TLDNode *new = tldnode_create(tld_name);
new->parent = node;
new->count++;
node->left = new;
return 1;
} else if ((comparison > 0) && (node->right == NULL)) {
/* case 4 */
TLDNode *new = tldnode_create(tld_name);
new->parent = node;
new->count++;
node->right = new;
return 1;
} else {
/* case 5 */
node->count++;
return 0;
}
}
/*
* tldlist_count returns the number of successful tldlist_add() calls since
* the creation of the TLDList
*/
long tldlist_count(TLDList *tld) {
return tld->count;
};
/*
* tldlist_iter_create creates an iterator over the TLDList; returns a pointer
* to the iterator if successful, NULL if not
*/
TLDIterator *tldlist_iter_create(TLDList *tld) {
return NULL;
};
/*
* tldlist_iter_next returns the next element in the list; returns a pointer
* to the TLDNode if successful, NULL if no more elements to return
*/
TLDNode *tldlist_iter_next(TLDIterator *iter) {
return NULL;
};
/*
* tldlist_iter_destroy destroys the iterator specified by `iter'
*/
void tldlist_iter_destroy(TLDIterator *iter) {
free(iter);
};
/*
* tldnode_create() creates a new node that contains a TLD name
* returns a pointer to the node if successful, NULL if not
*/
TLDNode *tldnode_create(char *element) {
TLDNode *node = (TLDNode *)malloc(sizeof(TLDNode));
if (node != NULL) {
node->parent = NULL;
node->left = NULL;
node->right = NULL;
node->count = 0;
}
return node;
}
/*
* tldnode_tldname returns the tld associated with the TLDNode
*/
char *tldnode_tldname(TLDNode *node) {
return node->element;
};
/*
* tldnode_count returns the number of times that a log entry for the
* corresponding tld was added to the list
*/
long tldnode_count(TLDNode *node) {
return node->count;
};
tldlist.h：
#ifndef _TLDLIST_H_INCLUDED_
#define _TLDLIST_H_INCLUDED_
#include "date.h"
typedef struct tldlist TLDList;
typedef struct tldnode TLDNode;
typedef struct tlditerator TLDIterator;
/*
* tldlist_create generates a list structure for storing counts against
* top level domains (TLDs)
*
* creates a TLDList that is constrained to the `begin' and `end' Date's
* returns a pointer to the list if successful, NULL if not
*/
TLDList *tldlist_create(Date *begin, Date *end);
/*
* tldlist_destroy destroys the list structure in `tld'
*
* all heap allocated storage associated with the list is returned to the heap
*/
void tldlist_destroy(TLDList *tld);
/*
* tldlist_add adds the TLD contained in `hostname' to the tldlist if
* `d' falls in the begin and end dates associated with the list;
* returns 1 if the entry was counted, 0 if not
*/
int tldlist_add(TLDList *tld, char *hostname, Date *d);
/*
* tldlist_count returns the number of successful tldlist_add() calls since
* the creation of the TLDList
*/
long tldlist_count(TLDList *tld);
/*
* tldlist_iter_create creates an iterator over the TLDList; returns a pointer
* to the iterator if successful, NULL if not
*/
TLDIterator *tldlist_iter_create(TLDList *tld);
/*
* tldlist_iter_next returns the next element in the list; returns a pointer
* to the TLDNode if successful, NULL if no more elements to return
*/
TLDNode *tldlist_iter_next(TLDIterator *iter);
/*
* tldlist_iter_destroy destroys the iterator specified by `iter'
*/
void tldlist_iter_destroy(TLDIterator *iter);
/*
* tldnode_tldname returns the tld associated with the TLDNode
*/
char *tldnode_tldname(TLDNode *node);
/*
* tldnode_count returns the number of times that a log entry for the
* corresponding tld was added to the list
*/
long tldnode_count(TLDNode *node);
#endif /* _TLDLIST_H_INCLUDED_ */
答案 0 :(得分：5)
这些错误是由缺少的原型引起的 - 你在tldlist.c中调用的函数，编译器还没有看到它的定义。
默认情况下，编译器假定任何未知函数返回int（遗留回送到很早的C，如果它将是int，则可以将返回类型保留为out）。这就是您获得不兼容类型消息的原因：）
您需要为编译器提供函数声明。您可以通过在tldlist.c顶部添加原型存根或通过创建定义它们的tldnode.h来实现这一点（因为它似乎主要是您缺少的与节点相关的函数）。
tldnode_create的实现是
TLDNode *tldnode_create(char *element) {
所以你需要声明
TLDNode *tldnode_create(char *element);
在尝试使用它之前：要么是tldnode.h，要么是tldlist.c顶部的某个地方，例如：在删除tldnode结构之后。
/*
* TODO: check the definition of element.
*/
struct tldnode {
struct tldnode *parent;
struct tldnode *left;
struct tldnode *right;
char *element;
long count;
};
TLDNode *tldnode_create(char *element);
答案 1 :(得分：1)
从顶部开始： 你的第一个警告是函数'tldnode_create'的隐式声明。 您应该在.h文件中定义此函数原型。 鉴于您无法修改它，您应该将原型放在.c文件的顶部
这会产生级联错误，因为编译器试图通过定义一个默认原型来提供帮助，该默认原型返回一个关于指针转换不兼容整数的整数（因此是你的下一个警告）。
另外，为什么声明函数是静态的？
答案 2 :(得分：1)
您正在调用未在头文件或c文件中定义的函数（在调用之前）。查看。 tldnode_create未在任何地方声明。也不是添加功能。
同样是我所看到的所有错误的问题。
在使用之前声明函数。