C++实现断点续传，单线程

#include "fileOperation.h" #include <iostream> #include <string.h> using namespace std; long bufSize = 10 * 1024; // 缓冲区大小 char* buffer; // 缓冲区保存文件数据 long sendedLength; // 客户端已经保存的数据长度 bool sendFile(SOCKET s, char* filePath,bool isDir) { if (isDir) { // 如果传进来的是文件夹 std::vector<std::string> vecFileInfo; findEx(filePath, vecFileInfo); if (vecFileInfo.size() > 0) { for (int i = 0; i < vecFileInfo.size(); i++) { char* fileName = new char[256]; memset(fileName, 0, 256); strcpy(fileName, (char*)vecFileInfo.at(i).c_str()); // 发送文件的完整路径名给client，用于创建文件夹和文件 char* filePathBuf = new char[256]; // 去掉server端的用户选中的文件夹 string strSrc(fileName); string strOld(filePath); string new_path = replace_all(strSrc, strOld, "."); strcpy(filePathBuf, (char*)new_path.c_str()); // 获取服务器上的文件大小 FILE* read = fopen(fileName, "rb"); if (!read) { perror("file open failed:\n"); return false; } long lFileSize = 0; fseek(read, 0, SEEK_END); lFileSize = ftell(read); fseek(read, 0, SEEK_SET); char dataLength[32]; memset(dataLength, 0, 32); ltoa(lFileSize, dataLength,10); char header[256]; memset(header, 0, 256); strcat(header, filePathBuf); strcat(header, "$"); strcat(header, dataLength); // 发送文件名称包括文件目录给client send(s, header, strlen(header),0); //long lLength = -2; recvRemoteFileLength(s, fileName); // 获取文件大小 if (sendedLength == 0) { fseek(read, 0, SEEK_END); bufSize = ftell(read); fseek(read, 0, SEEK_SET); cout << "filesize:" << bufSize << endl; } else { fseek(read, 0, SEEK_END); bufSize = ftell(read) - sendedLength; //fseek(read, 0, SEEK_SET); fseek(read, sendedLength, SEEK_CUR); if (bufSize <= 0) { fclose(read); memset(buffer, 0, bufSize); continue; } cout << "78 sendedLength filesize: " << bufSize << endl; } // 把文件读取到内存中 buffer = new char[bufSize]; //cout << sizeof(buffer) << endl; if (!buffer) { return false; } int nCount; int ret = 0; while ((nCount = fread(buffer, 1, bufSize, read)) > 0) { ret += send(s, buffer, nCount, 0); if (ret == SOCKET_ERROR) { err("sendFile"); return false; } } //shutdown(s, SD_SEND); recv(s, buffer, bufSize, 0); fclose(read); memset(buffer, 0, bufSize); cout << "send file success!" << "Byte:" << ret << endl; } } } else { const char* fileName = filePath; // 发送文件名称包括文件目录给client string strFileName(fileName); int index = strFileName.find_last_of("/"); string strLastFileName = strFileName.substr(index); strLastFileName = "./" + strLastFileName; // 获取文件大小 FILE* read = fopen(fileName, "rb"); if (!read) { perror("file open failed:\n"); return false; } long lFileSize = 0; fseek(read, 0, SEEK_END); lFileSize = ftell(read); fseek(read, 0, SEEK_SET); // 拼接文件目录和大小 char dataLength[32]; memset(dataLength, 0, 32); ltoa(lFileSize, dataLength, 10); char header[256]; memset(header, 0, 256); strcat(header, strLastFileName.c_str()); strcat(header, "$"); strcat(header, dataLength); send(s, header, strlen(header), 0); recvRemoteFileLength(s, fileName); // 获取文件大小 if (sendedLength == 0) { fseek(read, 0, SEEK_END); bufSize = ftell(read); fseek(read, 0, SEEK_SET); cout << "filesize:" << bufSize << endl; } else { fseek(read, 0, SEEK_END); bufSize = ftell(read) - sendedLength; //fseek(read, 0, SEEK_SET); fseek(read, sendedLength, SEEK_CUR); cout << "sendedLength filesize: " << bufSize << endl; } // 把文件读取到内存中 buffer = new char[bufSize]; cout << " 154 == "<< sizeof(buffer) << endl; if (!buffer) { return false; } int nCount; int ret = 0; while ((nCount = fread(buffer, 1, bufSize, read)) > 0) { ret += send(s, buffer, nCount, 0); if (ret == SOCKET_ERROR) { err("sendFile"); return false; } } //shutdown(s, SD_SEND); recv(s, buffer, bufSize, 0); fclose(read); memset(buffer, 0, bufSize); cout << "send file success!" << "Byte:" << ret << endl; } return true; } bool recvFile(SOCKET s,char* savePath) { // 接收server发送过来的文件路径，包括文件名 char* fileName = new char[256]; char* pathBuf = new char[256]; memset(pathBuf, 0, 256); char pathBufEx[256]; memset(pathBufEx, 0, 256); recv(s,pathBuf,256,0); // 获取到的路径是D:\\1\\,这种双反斜杠的格式 char payloadLength[32]; memset(payloadLength, 0, 32); for (int i = 0; i < strlen(pathBuf); i++) { if (pathBuf[i] == '$') { for (int j = 0; j < 32; j++) { if (pathBuf[i + 1 + j] != '\0') { payloadLength[j] = pathBuf[i + 1 + j]; } else { break; } } break; } else { pathBufEx[i] = pathBuf[i]; } } if (payloadLength != nullptr && strlen(payloadLength) == 0) { return false; } long fileLength = atol(payloadLength); cout << "167 == " << pathBufEx << " fileLength == "<< fileLength << endl; if (pathBufEx == nullptr || pathBufEx == "") { return false; } if (strstr(pathBufEx, "\\") != NULL) { replace_str(pathBufEx, '\\\\', '/'); } // 把接收到的文件夹目录加上本地的文件夹路径 strcat(savePath, "/"); std::string strA(pathBufEx); std::string strB(savePath); std::string strLocalPath = replace_all(strA,"./",strB); int index = strLocalPath.find_last_of("/"); string new_local_path = strLocalPath.substr(0, index); // 创建子文件夹和文件 createDirs((char*)new_local_path.c_str()); strcpy(fileName,strLocalPath.c_str()); cout << "187 == " << fileName << endl; if (buffer == NULL) { buffer = new char[bufSize]; if (!buffer) { return false; } } // 创建空文件 FILE* write = fopen(fileName, "ab+"); if (!write) { perror("file write failed:\n"); return false; } // 发送该文件是否在客户端存在，用于断点续传 sendLocalFileLength(s, fileName); int ret = 0; int nCount; long fileLastLength = 0; fileLastLength = fileLength - sendedLength; // 文件总大小减去已经发送的文件大小 if (fileLastLength <= 0) { fclose(write); return true; } while ((nCount = recv(s, buffer, bufSize, 0)) > 0) { ret = fwrite(buffer, nCount, 1, write); fileLastLength -= nCount; if (fileLastLength <= 0) { break; } } if (ret == 0) { cout << "server offline" << endl; } else if (ret < 0) { err("recv"); return false; } cout << "receive file success!" << endl; char lastBuf[1] = { '1' }; send(s, lastBuf, 1, 0); fclose(write); cout << "save file success! Filename:" << fileName << endl; //system("pause"); return true; } bool sendLocalFileLength(SOCKET s, const char * fileName) { long localFileLength = 0; FILE* read = fopen(fileName, "rb"); char buf[32] = { 0 }; if (!read) { perror("236 file open failed:\n"); localFileLength = 0; } else { // 获取本地文件的大小 fseek(read, 0, SEEK_END); localFileLength = ftell(read); fseek(read, 0, SEEK_SET); cout << "localFileLength:" << localFileLength << endl; } ltoa(localFileLength, buf, 10); if ((send(s, buf, strlen(buf), 0)) > 0) { cout << "localFileLength 6666:" << localFileLength; sendedLength = localFileLength; return true; } else { sendedLength = 0; } return false; } long recvRemoteFileLength(SOCKET s, const char * fileName) { char* buf = new char[32]; if (!buf) { return 0; } int nCount = recv(s, buf, 32, 0); if (nCount > 0) { sendedLength = atol(buf); } else { // 没�