Question

我想：

将包含vtkStringArray的vtkMultiBlockDataSet写入文件
加载
添加更多块
再次将其写入文件

您可以从here获得简化代码。

程序会产生段错误，但仅当编写器设置为二进制模式时，且仅当数据超过特定大小时才会生成。在ASCII模式下，一切都很好。

This可能是相关的。

你能证实这种行为吗？我究竟做错了什么？如果它是一个错误，我该如何解决？

非常感谢您的帮助。

编辑：我直接在这里添加示例代码（与上面给定的链接相同）：

#include <vtkSmartPointer.h>
#include <vtkPolyData.h>
#include <vtkPointData.h>
#include <vtkMultiBlockDataSet.h>
#include <vtkXMLMultiBlockDataWriter.h>
#include <vtkXMLMultiBlockDataReader.h>
#include <vtkStringArray.h>
#include <sys/stat.h>
#include <sstream>

int main(int, char *[])
{
    /**
     * notes:
     * -> it works with ascii writer configuration (BINARY=0) for any M,N.
     * -> with binary writer configuration (BINARY=1), it segfaults for higher M,N
     * -> {N=100,M=1} works. {N=100,M=10} fails. {N=1000,M=1} fails.
     */
    const unsigned int N = 1000; // number of points
    const unsigned int M = 1; // number of characters in the string
    const bool BINARY = 1; // 0=ascii, 1=binary

    std::string filename = "output/test_output.vtm";
    std::stringstream mystring;
    struct stat buffer;

    vtkSmartPointer<vtkPoints> points =
            vtkSmartPointer<vtkPoints>::New();
    vtkSmartPointer<vtkStringArray> stringAttribute =
            vtkSmartPointer<vtkStringArray>::New();
    vtkSmartPointer<vtkPolyData> mypolydata =
            vtkSmartPointer<vtkPolyData>::New();
    vtkSmartPointer<vtkMultiBlockDataSet> multiBDS =
            vtkSmartPointer<vtkMultiBlockDataSet>::New ();
    vtkSmartPointer<vtkXMLMultiBlockDataWriter> writer1 =
            vtkSmartPointer<vtkXMLMultiBlockDataWriter>::New();
    vtkSmartPointer<vtkMultiBlockDataSet> multiBDS_read =
            vtkSmartPointer<vtkMultiBlockDataSet>::New ();
    vtkSmartPointer<vtkXMLMultiBlockDataReader> reader =
            vtkSmartPointer<vtkXMLMultiBlockDataReader>::New();
    vtkSmartPointer<vtkXMLMultiBlockDataWriter> writer2 =
            vtkSmartPointer<vtkXMLMultiBlockDataWriter>::New();

    stringAttribute->SetNumberOfComponents(1);

    reader->SetFileName(filename.c_str());
    writer1->SetFileName(filename.c_str());
    writer2->SetFileName(filename.c_str());

    if (BINARY) {
        writer1->SetDataModeToBinary(); //segfault
        writer2->SetDataModeToBinary(); // segfault
    }
    else {
        writer1->SetDataModeToAscii(); // works
        writer2->SetDataModeToAscii(); // works
    }


    //create output folder and clear content:
    std::string outfolder = "output/";
    mkdir(outfolder.c_str(), 0777);
    system("exec rm -r output/*");

    // create some points:
    for (int k=0; k<N; ++k) {
        points->InsertNextPoint(0.0, 0.0, 0.0);
    }

    // create some string attributes:
    for (int k=0; k<N; ++k) {
        for (int i=0; i<M; ++i) {
            mystring << "x";
        }
        stringAttribute->InsertNextValue(mystring.str().c_str());
    }

    // assemble and write to file:
    mypolydata->SetPoints(points);
    mypolydata->GetPointData()->AddArray(stringAttribute);
    multiBDS->SetBlock(0,mypolydata);
    writer1->SetInput(multiBDS);
    writer1->Write();

    //now read the file again:
    if (stat (filename.c_str(), &buffer) == 0) {
        reader->Update();
        multiBDS_read->ShallowCopy(reader->GetOutput());
    }
    else {
        std::cout<<"file not found."<<std::endl;
    }

    // assemble and write again:
    //system("exec rm -r output/*"); // remove original file; not necessary
    multiBDS_read->SetBlock(multiBDS->GetNumberOfBlocks(),mypolydata);
    writer2->SetInput(multiBDS_read);
    writer2->Write();

    return EXIT_SUCCESS;
}

如果您使用cmake，请使用以下CMakeLists.txt：

cmake_minimum_required(VERSION 2.8)

PROJECT(vtk_weird_segfault)

find_package(VTK REQUIRED)
include(${VTK_USE_FILE})

add_executable(vtk_weird_segfault MACOSX_BUNDLE vtk_weird_segfault)

if(VTK_LIBRARIES)
  target_link_libraries(vtk_weird_segfault ${VTK_LIBRARIES})
else()
  target_link_libraries(vtk_weird_segfault vtkHybrid vtkWidgets)
endif()

将vtkStringArray写入文件时的vtk段错误

0 个答案: