mytget linux下的下载工具

/* Myget - A download accelerator for GNU/Linux * Homepage: http://myget.sf.net * Copyright (C) 2005- xiaosuo * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include <signal.h> #include <errno.h> #include "downloader.h" #include "macro.h" #include "utils.h" #include "ftpplugin.h" #include "httpplugin.h" #include "progressbar.h" #include "debug.h" typedef void* (*PthreadFunction) (void*); bool global_sigint_received = false; bool global_downloading = false; void catch_ctrl_c(int signo) { if(global_downloading){ global_sigint_received = true; }else{ pthread_exit(0); } }; Downloader::Downloader(void) { plugin = NULL; blocks = NULL; localPath = NULL; localMg = NULL; pb = new ProgressBar; signal(SIGPIPE, SIG_IGN); signal(SIGINT, &catch_ctrl_c); }; Downloader::~Downloader(void) { delete[] blocks; delete[] localPath; delete[] localMg; delete pb; delete plugin; signal(SIGPIPE, SIG_DFL); signal(SIGINT, SIG_DFL); }; int Downloader::init_plugin(void) { if(task.proxy.get_type() == HTTP_PROXY){ delete plugin; plugin = new HttpPlugin; }else{ switch(task.url.get_protocol()){ case HTTP: #ifdef HAVE_SSL case HTTPS: #endif delete plugin; plugin = new HttpPlugin; break; case FTP: delete plugin; plugin = new FtpPlugin; break; default: return -1; } } return 0; }; int Downloader::init_task(void) { int i; int ret; _reinit_plugin: if(init_plugin() < 0){ cerr<<"Unknown protocol"<<endl; return -1; } for(i = 0; task.tryCount <= 0 || i < task.tryCount; i ++){ ret = plugin->get_info(&task); if(ret == -1){ return -1; }else if(ret == S_REDIRECT){ cerr<<"Redirect to: "<<task.url.get_url()<<endl; goto _reinit_plugin; }else if(ret == 0){ return 0; }else{ continue; } } return E_MAX_COUNT; }; int Downloader::init_local_file_name(void) { int length; char *tmpStr; length = task.get_local_dir() ? strlen(task.get_local_dir()) : 1; length += task.get_local_file() ? strlen(task.get_local_file()) : strlen(task.url.get_file()); length += 6; tmpStr = new char[length]; snprintf( tmpStr, length, "%s/%s.mg!", task.get_local_dir() ? task.get_local_dir() : ".", task.get_local_file() ? task.get_local_file() : task.url.get_file() ); delete[] localPath; delete[] localMg; tmpStr[length - 5] = '\0'; localPath = StrDup(tmpStr); tmpStr[length - 5] = '.'; localMg = tmpStr; return 0; }; int Downloader::init_threads_from_mg(void) { FILE *fd; int i; struct stat file_stat; if(stat(localMg, &file_stat) < 0){ perror("Can not get the info of the temp file"); return -1; } if(file_stat.st_size < task.fileSize + sizeof(threadNum)){ cerr<<"the temp file: \""<<localMg<<"\" is not correct"<<endl; return -1; } fd = fopen(localMg, "r"); if(fd == NULL && errno == EACCES){ cerr<<"Can not access the temp file: "<<localMg<<endl; return -1; } fseeko(fd, task.fileSize, SEEK_CUR); fread(&threadNum, sizeof(threadNum), 1, fd); if(file_stat.st_size != task.fileSize + sizeof(threadNum) + sizeof(off_t)*threadNum*3){ cerr<<"the temp file: \""<<localMg<<"\" is not correct"<<endl; fclose(fd); return -1; } delete[] blocks; blocks = new Block[threadNum]; for(i = 0; i < threadNum; i ++){ fread(&blocks[i].startPoint, sizeof(off_t), 1, fd); fread(&blocks[i].downloaded, sizeof(off_t), 1, fd); fread(&blocks[i].size, sizeof(off_t), 1, fd); if(blocks[i].bufferFile.open(localMg) < 0){ perror("Can not open the temp file to write"); return -1; } } fclose(fd); return 0; }; int Downloader::init_threads_from_info(void) { off_t block_size; int i; threadNum = task.threadNum > 0 ? task.threadNum : 1; block_size = task.fileSize / threadNum; if(block_size <= 0){ // too small file threadNum = 1; block_size = task.fileSize; } delete[] blocks; blocks = new Block[threadNum]; for(i = 0; i < threadNum; i ++){ blocks[i].startPoint = i * block_size; blocks[i].size = block_size; if(blocks[i].bufferFile.open(localMg) < 0){ perror("Can not open the temp file to write"); return -1; } } blocks[threadNum - 1].size = task.fileSize - block_size * ( threadNum - 1); return 0; }; int Downloader::thread_create(void) { pthread_t pid; int i; while(1){ i = pthread_create(&pid, NULL, (PthreadFunction)&download_thread, (void*)this); if(i == 0) break; usleep(250000); } for(i = 0; i < threadNum; i ++){ if(blocks[i].pid == 0){ // found an empty slot blocks[i].pid = pid; break; } } if(i == threadNum) return -1; return 0; }; // return the source'id of the current thread int Downloader::self(void) { pthread_t self; self = pthread_self(); int i; while(1){ for(i = 0; i < threadNum; i ++){ if(blocks[i].pid == self) return i; } // the parent thread maybe slower than me } }; // this function will be called by pthread_create, because c++ // not allow non-static function convert to the right function, // so make it static, but this will be safe int Downloader::download_thread(Downloader *downloader) { int self, ret, i; self = downloader->self(); /* for(i = 0; downloader->task.tryCount <= 0 || i < downloader->task.tryCount; i ++){ */ while(1){ ret = downloader->plugin->download(downloader->task, downloader->blocks + self); if(ret == E_SYS){ // system error downloader->blocks[self].state = EXIT; return -1; }else if(ret == 0){ downloader->blocks[self].state = EXIT; return 0; }else{ continue; } } downloader->blocks[self].state = EXIT; return E_MAX_COUNT; }; // schedule the thread, when the thread exit joined it or wake up it if // the next thread have not begun to downloading from the serve, // return the number of the running threads int Downloader::schedule(void) { int i, j; int joined; joined = 0; for(i = 0; i < threadNum; i ++){ if(blocks[i].state == WAIT){ for(j = i + 1; j < threadNum; j ++){ if(blocks[i].startPoint + blocks[i].size == blocks[j].startPoint){ break; } } if(j < threadNum && blocks[j].downloaded == 0){ if(blocks[j].state == STOP || blocks[j].state == EXIT){ pthread_cancel(blocks[j].pid); pthread_join(blocks[j].pid, NULL); blocks[j].state = JOINED; blocks[j].bufferFile.close(); }else if(blocks[j].state != JOINED){ continue; } blocks[i].size += blocks[j].size; blocks[i].state = WAKEUP; blocks[j].startPoint = -1; blocks[j].downloaded = 0; blocks[j].size = 0; i = j; joined += j - i; off_t *data = new off_t[threadNum]; for(j = 0; j < threadNum; j ++){ data[j] = blocks[j].startPoint; } pb->set_start_point(data); delete[] data; } }else if(blocks[i].state == EXIT){ pthread_join(blocks[i].pid, NULL); blocks[i].state = JOINED; blocks[i].bufferFile.close(); joined ++; }else if(blocks[i].state == JOINED){ joined ++; }else{ continue; } } return threadNum - joined; }; // end of schedule int Downloader::save_temp_file_exit(void) { int i; FILE *fd; for(i = 0; i < threadNum; i ++){ if(blocks[i].state != JOINED){ pthread_cancel(blocks[i].pid); pthread_join(blocks[i].pid, NULL); blocks[i].bufferFile.close(); } }; // if know the filesize, maybe can resume through other link address // but if the filesize is unknow