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问题：浏览器与文件服务器如何交互？
浏览器与文件服务器的交互
-
文件浏览
- 点击列表中的文件夹 → 进入子文件夹（展现子文件夹列表）
-
文件下载
- 点击列表中的文件 → 下载指标文件
-
错误处理
- 向服务器发送谬误申请 → 浏览不存在的文件夹 / 下载不存在的文件
文件浏览交互实现
实现中的要害概念
-
共享文件夹（root）
- 服务端启动时指定的共享文件夹门路（服务零碎中的门路）
-
申请门路（req）
- 文件 / 文件夹 在服务端上绝对共享文件夹的门路
-
绝对路径
AbsPath = root + "/" + req
根底函数定义
-
char *GetAbsPath(const char *relative, const char *root)- 拼接 root 和 relative, 返回绝对路径，返回值需开释（free）
-
int isDotPath(const char *path)- 判断 path 是否为非凡门路 “.” 或 “..”
-
int GetEntryCount(const char *path)- 返回 path 门路下的（文件 + 文件夹）总数
编程试验：根底函数实现
static char *GetAbsPath(const char *relative, const char *root)
{int reLen = strlen(relative);
int rootLen = strlen(root);
char *ret = malloc(reLen + rootLen + 2);
if (ret) {strcpy(ret, root);
if ((relative[0] == '/') && (ret[rootLen-1] == '/')) ret[rootLen - 1] = 0;
if ((relative[0] != '/') && (ret[rootLen-1] != '/')) strcat(ret, "/");
strcat(ret, relative);
}
return ret;
}
static int IsDotPath(const char *path)
{
int ret = -1;
if (path) {ret = (strcmp(path, ".") == 0) || (strcmp(path, "..") == 0);
}
return ret;
}
static int GetEntryCount(const char *path)
{
int ret = -1;
DIR *dirp = opendir(path);
if (dirp != NULL) {
struct dirent *dp = NULL;
ret = 0;
while ((dp = readdir(dirp)) != NULL) {if (!IsDotPath(dp->d_name)) {ret ++;}
}
}
closedir(dirp);
return ret;
}要害数据结构定义
enum {
TypeAll = 0x00,
TypeDir = 0x04,
TypeFile = 0x08
};
typdef struct {
const int length;
RowInfo data[];}FileEntry;
typedef struct {char link[2048];
char name[255];
char type[32];
char size[32];
char time[32];
}RowInfo;要害函数定义
-
int MakeEntryItem(RowInfo *item, struct dirent *dp, const char *ap, const char *req);- 依据 dp 所指向的 文件 或 文件夹 生成 RowInfo 数据结构，胜利返回 true, 失败返回 false
-
FileEntry *GetEntry(const char *req, const char *root, int type);- 获取 root/req 门路下 文件 和 文件夹 所对应的 RowInfo 数组，返回值需开释（free）
-
char *MakeHTML(const char *req, const char *root);- 创立 root/req 门路下 文件 和 文件夹 所形成的 HTML 页面，返回值需开释（free）
服务端实现设计
非凡页面设计
编程试验：文件浏览交互实现
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <dirent.h>
#include <unistd.h>
#include <time.h>
#include "page.h"
#include "response.h"
enum {TypeAll = 0x00, TypeDir = 0x04, TypeFile = 0x08};
typedef struct
{
const int length;
RowInfo data[];} FileEntry;
static char* GetAbsPath(const char* relative, const char* root)
{int reLen = strlen(relative);
int rootLen = strlen(root);
char* ret = malloc(reLen + rootLen + 2);
if(ret) {strcpy(ret, root);
if((relative[0] == '/') && (ret[rootLen-1] == '/') ) ret[rootLen-1] = 0;
if((relative[0] != '/') && (ret[rootLen-1] != '/') ) strcat(ret, "/");
strcat(ret, relative);
}
return ret;
}
static int IsDotPath(const char* path)
{
int ret = -1;
if(path) {ret = (strcmp(path, ".") == 0) || (strcmp(path, "..") == 0);
}
return ret;
}
static int GetEntryCount(const char* path)
{
int ret = -1;
DIR* dirp = opendir(path);
if(dirp != NULL) {
struct dirent* dp = NULL;
ret = 0;
while((dp = readdir(dirp)) != NULL ) {if( !IsDotPath(dp->d_name) ) {ret++;}
}
}
closedir(dirp);
return ret;
}
static void SortFileEntry(FileEntry* fe)
{RowInfo* temp = malloc(sizeof(*temp));
if(fe && temp) {
int i = 0;
int j = 0;
for(i=0; i<fe->length; i++) {
int min = i;
for(j=i; j<fe->length; j++) {if( strcmp(fe->data[min].name, fe->data[j].name) > 0 ) {min = j;}
}
*temp = fe->data[i];
fe->data[i] = fe->data[min];
fe->data[min] = *temp;
}
}
free(temp);
}
static int MakeEntryItem(RowInfo* item, struct dirent* dp, const char* ap, const char* req)
{
int ret = 0;
char buf[32] = {0};
struct stat sb = {0};
char* path = GetAbsPath(dp->d_name, ap);
if(path && (ret = (stat(path, &sb)) != -1) )
{strcpy(item->link, req);
(strcmp(req, "/") != 0) ? strcat(item->link, "/") : 0;
strcat(item->link, dp->d_name);
strcpy(item->name, dp->d_name);
if(dp->d_type == TypeFile) {strcpy(item->type, "File");
if(sb.st_size < 1024) {sprintf(buf, "%ld", sb.st_size);
strcpy(item->size, buf);
strcat(item->size, "Byte");
}
else if((sb.st_size / 1024) < 1024 ) {sprintf(buf, "%ld", sb.st_size/1024);
strcpy(item->size, buf);
strcat(item->size, "KB");
}
else {sprintf(buf, "%ld", sb.st_size/1024/1024);
strcpy(item->size, buf);
strcat(item->size, "MB");
}
}
else {strcpy(item->type, "Folder");
sprintf(buf, "%d", GetEntryCount(path));
strcpy(item->size, buf);
strcat(item->size, "Item");
}
strcpy(item->time, ctime(&sb.st_mtime));
}
free(path);
return ret;
}
static FileEntry* GetEntry(const char* req, const char* root, int type)
{char* ap = GetAbsPath(req, root);
DIR* dirp = NULL;
FileEntry* ret = NULL;
if(ap && (dirp = opendir(ap)) ) {
const int STEP = 5;
struct dirent* dp = NULL;
int max = 0;
int* pLen = NULL;
ret = malloc(sizeof(*ret));
if(ret) {pLen = (int*)&ret->length;
*pLen = 0;
}
while(pLen && ((dp = readdir(dirp)) != NULL) ) {if( *pLen == max) {
max = max + STEP;
ret = realloc(ret, sizeof(*ret) + sizeof(RowInfo) * max);
pLen = (int*)&ret->length;
}
if(ret && ((type == TypeAll) || (type == dp->d_type)) ) {if( !IsDotPath(dp->d_name) && MakeEntryItem(&ret->data[*pLen], dp, ap, req) )
{*pLen = *pLen + 1;}
}
}
SortFileEntry(ret);
}
free(ap);
closedir(dirp);
return ret;
}
static char* MakeHTML(const char* req, const char* root)
{
char* ret = NULL;
Table* table = CreateTable();
if(table) {
FileEntry* fe = NULL;
char* ts = NULL;
char* resp = NULL;
RowInfo* back = NULL;
int i = 0;
if((strcmp(req, "/") != 0) && (back = calloc(1, sizeof(*back))) ) {i = strlen(req) - 1;
strcpy(back->link, req);
while(back->link[i] != '/' ) i--;
i ? (back->link[i] = 0) : (back->link[i+1] = 0);
strcpy(back->name, "./..");
strcpy(back->type, "Back..");
table = InsertRow(table, back);
}
free(back);
fe = GetEntry(req, root, TypeDir);
for(i=0; fe && (i<fe->length); i++) {table = InsertRow(table, &fe->data[i]);
}
free(fe);
fe = GetEntry(req, root, TypeFile);
for(i=0; fe && (i<fe->length); i++) {table = InsertRow(table, &fe->data[i]);
}
free(fe);
ts = ToTableString(table);
ret = ts ? ToPageString(req, ts) : NULL;
free(ts);
}
FreeTable(table);
return ret;
}
static int Response(TcpClient* client, const char* html)
{
const char* HTTP_FORMAT = "HTTP/1.1 200 OK\r\n"
"Server:Test Http Server\r\n"
"Content-Length:%d\r\n"
"Content-Type:text/html\r\n"
"Connection:close\r\n\r\n"
"%s";
int ret = 0;
if(html) {char* resp = malloc(strlen(HTTP_FORMAT) + strlen(html) + 16);
if(resp) {sprintf(resp, HTTP_FORMAT, strlen(html), html);
ret = (TcpClient_SendRaw(client, resp, strlen(resp)) > 0);
}
free(resp);
}
return ret;
}
static int DirReqHandler(TcpClient* client, const char* req, const char* root)
{char* html = MakeHTML(req, root);
int ret = Response(client, html);
free(html);
return ret;
}
int RequestHandler(TcpClient* client, const char* req, const char* root)
{
int ret = 0;
if(client && req && root) {ret = DirReqHandler(client, req, root);
}
return ret;
}思考
favicon.ico 是什么？如何解决？
正文完