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2068 :: error on: newWideCString

• Kerp (orginal) [2016-02-24T20:52:57+01:00] view original

  getting a strange error when i try to read a text file on my windows 8.1 machine.

  basically i tried only opening the file and read it with the readAll proc but both it and readFile proc do not read the file.

  i'm using gcc 5.3 mingw64 but i'm stumped on this one maybe file encoding issue i don't know.

  anybody run into this?

  edit: forgot to mention getting segmentation fault on when it tries to read this file.

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• OderWat (orginal) [2016-02-24T21:05:02+01:00] view original

  Maybe you want to show us your code? system.readAll() and system.readFile() are in no way related to WideCStrings afaik. Both read a string which is a "binary" char representation and encoding does not matter until you interpret it as one of the possible encodings.

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• Kerp (orginal) [2016-02-24T22:20:56+01:00] view original

  here is the code i'm having trouble with

  
  import "opengl-1.0/opengl"
  
  var
    vert_atr*: GLuint
    mvp_id*: GLuint
    prog_id*:GLint
    p_id*:GLuint
  
  proc create_frag(shader:string): GLuint
  proc create_vert(shader:string): GLuint
  
  proc readUserFile(name:string): array[1,string] =
    var file: FILE
    if open(file,name) == true:
      result = [readAll(file).string]
      close(file)
    else:
      echo("error on file: ", name)
      close(file)
  
  
  proc create_program*(f,v: string) =
    prog_id = glCreateProgram()
    glAttachShader(prog_id.GLuint,create_frag(f))
    glAttachShader(prog_id.GLuint,create_vert(v))
    
    #glBindAttribLocation(cast[GLuint](prog_id),1,"vertexs")
    #glBindAttribLocation(prog_id,2,"MVP")
    glLinkProgram(prog_id.GLuint)
    glValidateProgram(prog_id.GLuint)
    
    vert_atr = glGetAttribLocation(prog_id.GLuint,"vertexs")
    mvp_id = glGetUniformLocation(prog_id.GLuint,"MVP")
    p_id = glGetUniformLocation(prog_id.GLuint,"P")
    #echo ("mvp id: ", mvp_id, "prog_id: " , prog_id)
    var status: GLint
    glGetProgramiv(prog_id.GLuint,GL_LINK_STATUS.GLenum,addr status)
    
    if status == GLint(0):
      echo "program did not link"
      quit()
  
  proc create_frag(shader:string): GLuint =
      var format : array[1,string] = readUserFile(shader)
      var shader_id = glCreateShader(GL_FRAGMENT_SHADER.GLenum)
      var source = allocCstringArray(format)
      
      glShaderSource(shader_id,GLsizei(1),source,nil)
      glCompileShader(shader_id)
      deallocCstringArray(source)
      
      var status : GLint = 0;
      glGetShaderiv(shader_id,GL_COMPILE_STATUS.GLenum,addr status)
      
      if status == GLint(0):
        var msgsize : GLsizei
        glGetShaderiv(shader_id,GL_INFO_LOG_LENGTH,msgsize.addr);
        var message : cstring
        glGetShaderInfoLog(shader_id,GLsizei(1000),msgsize.addr,message)
        echo message
        quit()
      return shader_id
  
  proc create_vert(shader:string): GLuint =
      var format : array[1,string] = readUserFile(shader)
      var shader_id = glCreateShader(GL_VERTEX_SHADER.GLenum)
      var source = allocCstringArray(format)
      
      glShaderSource(shader_id,GLsizei(1),source,nil)
      glCompileShader(shader_id)
      deallocCstringArray(source)
      
      var status : GLint = 0;
      glGetShaderiv(shader_id,GL_COMPILE_STATUS.GLenum,addr status)
      
      if status == GLint(0):
        var msgsize : GLsizei
        glGetShaderiv(shader_id,GL_INFO_LOG_LENGTH,msgsize.addr);
        var message : cstring
        glGetShaderInfoLog(shader_id,GLsizei(1000),msgsize.addr,message)
        echo message
        quit()
      return shader_id
  
  
  Run

  and here is the traceback

  
  Traceback (most recent call last)
  main.nim(68)             main
  main.nim(50)             main
  model_handler.nim(12)    init
  model.nim(26)            create
  program.nim(24)          create_program
  program.nim(44)          create_frag
  program.nim(14)          readUserFile
  sysio.nim(267)           open
  sysio.nim(243)           fopen
  widestrs.nim(111)        newWideCString
  SIGSEGV: Illegal storage access. (Attempt to read from nil?)
  > Process terminated with exit code 1
  
  Run

  as we can see widestr.nim is for some reason being called

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• OderWat (orginal) [2016-02-24T22:35:19+01:00] view original

  My guess is, that newWideCString() is called to create the filename for the windows system open function. I would debug that name first.

  EDIT: I looked up what sysio.nim in line 243 does (see your stacktrace)

  when defined(cpp):
      proc wfopen(filename, mode: WideCString): pointer {.
        importcpp: "_wfopen((const wchar_t*)#, (const wchar_t*)#)", nodecl.}
  Run

  So there is a problem with the "filename" or "mode". Hope that helps you to find the problem!

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• Kerp (orginal) [2016-02-26T08:43:28+01:00] view original

  well i simplified that offending code after my program.nim file and now it runs fine. So my guess is that somewhere in the seq's i was using the filename was nil.

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