Segmentation fault, if --mesh folder does not exist or contains wrong data

[BenjaminRodenberg]

When reviewing precice/tutorials#73 I forgot to convert the output data to aste format using precice_to_aste.py as described in the tutorial's README.md. Therefore the folder preCICE-output only contained preCICE-output/Solid-fenics.dt*.vtk files. However, aste expects preCICE-output/Solid-fenics.dt* to work properly.

Running ./preciceMap -v -c precice-config.xml -p A --mesh preCICE-output/Solid-fenics led to a segmentation fault:

benjamin@benjamin-ThinkPad-X1-Yoga-2nd:~/aste/build$ ./preciceMap -v -c precice-config.xml -p A --mesh preCICE-output/Solid-fenics
2020-05-08 16:11:01,513 VERBOSE-1 [default] Basename: preCICE-output/Solid-fenics
2020-05-08 16:11:01,513 DEBUG [default] [benjamin@unknown-host] [std::vector<std::__cxx11::basic_string<char> > getMeshes(std::__cxx11::string, int)] [/home/benjamin/aste/src/preciceMap.cpp:47] Meshes:
(0) 16:11:01 [impl::SolverInterfaceImpl]:120 in configure: This is preCICE version 2.0.2
(0) 16:11:01 [impl::SolverInterfaceImpl]:121 in configure: Revision info: v2.0.1-146-g15fb6857-dirty
(0) 16:11:01 [impl::SolverInterfaceImpl]:122 in configure: Configuring preCICE with configuration "precice-config.xml"
(0) 16:11:01 [impl::SolverInterfaceImpl]:123 in configure: I am participant "A"
[benjamin-ThinkPad-X1-Yoga-2nd:11346] *** Process received signal ***
[benjamin-ThinkPad-X1-Yoga-2nd:11346] Signal: Segmentation fault (11)
[benjamin-ThinkPad-X1-Yoga-2nd:11346] Signal code: Address not mapped (1)
[benjamin-ThinkPad-X1-Yoga-2nd:11346] Failing at address: (nil)
[benjamin-ThinkPad-X1-Yoga-2nd:11346] [ 0] /lib/x86_64-linux-gnu/libpthread.so.0(+0x12890)[0x7f4be1993890]
[benjamin-ThinkPad-X1-Yoga-2nd:11346] [ 1] /usr/lib/x86_64-linux-gnu/libstdc++.so.6(_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE5c_strEv+0x0)[0x7f4be1212470]
[benjamin-ThinkPad-X1-Yoga-2nd:11346] [ 2] ./preciceMap(_ZN2el4base14MessageBuilderlsERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE+0x1c)[0x5646e908d448]
[benjamin-ThinkPad-X1-Yoga-2nd:11346] [ 3] ./preciceMap(_ZN2el4base6WriterlsINSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEEEERS1_RKT_+0x33)[0x5646e908e0c7]
[benjamin-ThinkPad-X1-Yoga-2nd:11346] [ 4] ./preciceMap(_Z12readMainFileR4MeshRKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEEb+0x120)[0x5646e9082cfc]
[benjamin-ThinkPad-X1-Yoga-2nd:11346] [ 5] ./preciceMap(_Z8readMeshRKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEEb+0x60)[0x5646e9083534]
[benjamin-ThinkPad-X1-Yoga-2nd:11346] [ 6] ./preciceMap(main+0x3dd)[0x5646e9083ab8]
[benjamin-ThinkPad-X1-Yoga-2nd:11346] [ 7] /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xe7)[0x7f4be0b04b97]
[benjamin-ThinkPad-X1-Yoga-2nd:11346] [ 8] ./preciceMap(_start+0x2a)[0x5646e90821da]
[benjamin-ThinkPad-X1-Yoga-2nd:11346] *** End of error message ***
Segmentation fault (core dumped)

When does the error occur, how to improve it?

This Segmentation fault occurs in two cases:

1. The --mesh folder does not exist.
2. The folder exists, but contains wrong data (like explained above)

A meaningful error message would be more helpful than a segmentation fault.

Reproduce the error

The error can be reproduced by using the attached preCICE-output.zip folder and running ./preciceMap -v -c preCICE-output/precice-config.xml -p A --mesh preCICE-output/Solid-fenics from aste/build. (I've put the precice-config.xml into that folder to simplify the upload.)

[fsimonis]

This was fixed by 2f3a529