libuuu/tar.cpp

   1 /*
   2  * Copyright 2020 NXP.
   3  *
   4  * Redistribution and use in source and binary forms, with or without modification,
   5  * are permitted provided that the following conditions are met:
   6  *
   7  * Redistributions of source code must retain the above copyright notice, this
   8  * list of conditions and the following disclaimer.
   9  *
  10  * Redistributions in binary form must reproduce the above copyright notice, this
  11  * list of conditions and the following disclaimer in the documentation and/or
  12  * other materials provided with the distribution.
  13  *
  14  * Neither the name of the NXP Semiconductor nor the names of its
  15  * contributors may be used to endorse or promote products derived from this
  16  * software without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  21  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
  22  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  28  * POSSIBILITY OF SUCH DAMAGE.
  29  *
  30  */
  31
  32 #include <stdint.h>
  33 #include <map>
  34 #include <string>
  35 #include <vector>
  36 #include "zlib.h"
  37 #include <memory>
  38 #include "buffer.h"
  39 #include "liberror.h"
  40 #include "libuuu.h"
  41 #include <stdio.h>
  42 #include <string.h>
  43 #include "tar.h"
  44 #include <fstream>
  45 #include <iostream>
  46 using namespace std;
  47
  48 int Tar::Open(const string &filename)
  49 {
  50         bool end_of_file=false;
  51         char end_of_file_blocks[2*TAR_BLOCK_SIZE];
  52         memset(end_of_file_blocks, 0, sizeof(end_of_file_blocks) );
  53         m_tarfilename=filename;
  54
  55         shared_ptr<FileBuffer> file = get_file_buffer(filename);
  56         if(file == nullptr)
  57                 return -1;
  58
  59         uint8_t* data=file->data();
  60         uint64_t block_counter=0;
  61         while(!end_of_file)
  62         {
  63                 if(!memcmp(end_of_file_blocks,data+block_counter*TAR_BLOCK_SIZE,TAR_BLOCK_SIZE))
  64                 {
  65                         end_of_file=true;
  66                         break;
  67                 }
  68                 struct Tar_header* th=(Tar_header*)(data+block_counter*TAR_BLOCK_SIZE);
  69                 uint64_t size;
  70                 string octal_str((char*)th->size);
  71                 //printf("block_counter: %d\n",block_counter );
  72                 //printf("name: %s\n",th->name );
  73                 //printf("signature: %s\n",th->ustar );
  74                 //printf("size: %s\n", th->size);
  75                 size=stoll(octal_str, 0, 8);
  76                 string name((char*)th->name);
  77                 m_filemap[name].size=size;
  78                 m_filemap[name].offset=(block_counter+1)*TAR_BLOCK_SIZE; //+1 because the data located right after the header block
  79                 m_filemap[name].filename.assign((char*)th->name);
  80                 block_counter++;
  81
  82                 //skip the data blocks
  83                 uint64_t data_block_num=size/TAR_BLOCK_SIZE;
  84                 data_block_num += (size%TAR_BLOCK_SIZE>0)? 1:0;
  85                 block_counter+=data_block_num;
  86         }
  87         return 0;
  88 }
  89
  90 bool Tar::check_file_exist(const string &filename)
  91 {
  92
  93         if (m_filemap.find(filename) == m_filemap.end())
  94         {
  95                 string err;
  96                 err += "Can't find file ";
  97                 err += filename;
  98                 set_last_err_string(err);
  99                 return false;
 100         }
 101
 102         return true;
 103 }
 104
 105
 106 int Tar::get_file_buff(const string &filename, shared_ptr<FileBuffer> p )
 107 {
 108
 109         if (m_filemap.find(filename) == m_filemap.end())
 110         {
 111                 string err;
 112                 err += "Can't find file ";
 113                 err += filename;
 114                 set_last_err_string(err);
 115                 return -1;
 116         }
 117
 118         p->resize(m_filemap[filename].size);
 119         atomic_fetch_or(&p->m_dataflags, FILEBUFFER_FLAG_KNOWN_SIZE);
 120         p->m_request_cv.notify_all();
 121
 122         shared_ptr<FileBuffer> file;
 123         file = get_file_buffer(m_tarfilename);
 124         size_t offset= m_filemap[filename].offset;
 125         size_t size=m_filemap[filename].size;
 126
 127         p->ref_other_buffer(file, offset, size);
 128         atomic_fetch_or(&p->m_dataflags, FILEBUFFER_FLAG_LOADED);
 129         p->m_request_cv.notify_all();
 130
 131         return 0;
 132 }
 133