"humbleaptience" <humblepatie***@gmail.com> wrote in message
news:1157637467.040651.285180@d34g2000cwd.googlegroups.com...
>I have a web application that uses a DLL using DLLImport.
>
> Twice I have put the application live on the net and it has been used
> hundreds or thousands of time before it has been strangely brought
> down.
>
> System.AccessViolationException: Attempted to read or write protected
> memory. This is often an indication that other memory is corrupt. at
> ProjApi.Proj.pj_init_plus(String pjstr) at coordinate.LLtoUTM(Int32
> datumIn, Int32 datumOut, Double p_lat, Double p_lon, Double&
> UTMNorthing, Double& UTMEasting, Int32& UTMZone) at
> coordinate.LLtoUTMZone(Double lat, Double lon, Int32 datumIn, Int32
> datumOut, Int32& z, Double& n, Double& e) at
> getfactory.Page_Load(Object sender, EventArgs e) at
> System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o,
> Object t, EventArgs e) at
> System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender,
> EventArgs e) at System.Web.UI.Control.OnLoad(EventArgs e) at
> System.Web.UI.Control.LoadRecursive() at
> System.Web.UI.Page.ProcessRequestMain(Boolean
> includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)
>
> Here is my code that calls the extern method
>
> public static int LLtoUTM(int datumIn, int datumOut, double p_lat,
> double p_lon,ref double UTMNorthing,ref double UTMEasting,ref int
> UTMZone)
> {
>            int errno = 0;
> //This is the formula for calculating which Zone a point is in at a
> particular lat/long
> int ZoneNumber = Convert.ToInt32(Math.Floor((p_lon + 180) / 6)) + 1;
> double[] x = new double[1];
> double[] y = new double[1];
> double[] z = new double[1];
>            y[0] = p_lat * ProjApi.Proj.DEG_TO_RAD;
>            x[0] = p_lon * ProjApi.Proj.DEG_TO_RAD;
> z[0] = 0.0;
>            IntPtr src0 = ProjApi.Proj.pj_init_plus("+proj=latlong
> +datum=NAD27");
>            IntPtr src1 = ProjApi.Proj.pj_init_plus("+proj=latlong
> +datum=NAD83");
>            IntPtr dst0 = ProjApi.Proj.pj_init_plus("+proj=utm +zone="
> + ZoneNumber + " +datum=NAD27");
>            IntPtr dst1 = ProjApi.Proj.pj_init_plus("+proj=utm +zone="
> + ZoneNumber + " +datum=NAD83");
> //This nice little bit of code below is designed to execute
> pj_transfrom (the proj lib all around function)
> //with the correct parameters so that a datumshift to the correct
> datum is included.
>            try
>            {
>                if (datumIn == 0)
>                {
>                    if (datumOut == 0)
>                    {
>                        errno = ProjApi.Proj.pj_transform(src0, dst0,
> 1, 1, x, y, z);//NAD27-NAD83
>                    }
>                    else
>                    {
>                        errno = ProjApi.Proj.pj_transform(src0, dst1,
> 1, 1, x, y, z);//NAD27-NAD27
>                    }
>                }
>                else
>                {
>                    if (datumOut == 0)
>                    {
>                        errno = ProjApi.Proj.pj_transform(src1, dst0,
> 1, 1, x, y, z);//NAD83-NAD27
>                    }
>                    else
>                    {
>                        errno = ProjApi.Proj.pj_transform(src1, dst1,
> 1, 1, x, y, z);//NAD83-NAD83
>                    }
>                }
>            }
>            catch { }
>
>            ProjApi.Proj.pj_free(dst1);
>            ProjApi.Proj.pj_free(src1);
>            ProjApi.Proj.pj_free(dst0);
>            ProjApi.Proj.pj_free(src0);
> UTMNorthing = y[0];
> UTMEasting = x[0];
> UTMZone = ZoneNumber;
> return errno;
> }
>
>
> Here is the definition and DLL import.
>        [DllImport("proj.dll", CharSet = CharSet.Ansi,
> CallingConvention = CallingConvention.Cdecl)]
>        public static extern unsafe int pj_transform(IntPtr src, IntPtr
> dst,
>            int point_count, int point_offset,
>            [InAttribute, OutAttribute] double[] x,
>            [InAttribute, OutAttribute] double[] y,
>            [InAttribute, OutAttribute] double[] z);
>
> Any help at all would be useful. I am not able to trigger this error
> myself so I can't even do trial and error.
>

> Did you develop unmanaged proj.dll? Do you source for that DLL?
> That code seems to be causing some meory overwrite.
>
> "humbleaptience" <humblepatie***@gmail.com> wrote in message
> news:1157637467.040651.285180@d34g2000cwd.googlegroups.com...
> >I have a web application that uses a DLL using DLLImport.
> >
> > Twice I have put the application live on the net and it has been used
> > hundreds or thousands of time before it has been strangely brought
> > down.
> >
> > System.AccessViolationException: Attempted to read or write protected
> > memory. This is often an indication that other memory is corrupt. at
> > ProjApi.Proj.pj_init_plus(String pjstr) at coordinate.LLtoUTM(Int32
> > datumIn, Int32 datumOut, Double p_lat, Double p_lon, Double&
> > UTMNorthing, Double& UTMEasting, Int32& UTMZone) at
> > coordinate.LLtoUTMZone(Double lat, Double lon, Int32 datumIn, Int32
> > datumOut, Int32& z, Double& n, Double& e) at
> > getfactory.Page_Load(Object sender, EventArgs e) at
> > System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o,
> > Object t, EventArgs e) at
> > System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender,
> > EventArgs e) at System.Web.UI.Control.OnLoad(EventArgs e) at
> > System.Web.UI.Control.LoadRecursive() at
> > System.Web.UI.Page.ProcessRequestMain(Boolean
> > includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)
> >
> > Here is my code that calls the extern method
> >
> > public static int LLtoUTM(int datumIn, int datumOut, double p_lat,
> > double p_lon,ref double UTMNorthing,ref double UTMEasting,ref int
> > UTMZone)
> > {
> >            int errno = 0;
> > //This is the formula for calculating which Zone a point is in at a
> > particular lat/long
> > int ZoneNumber = Convert.ToInt32(Math.Floor((p_lon + 180) / 6)) + 1;
> > double[] x = new double[1];
> > double[] y = new double[1];
> > double[] z = new double[1];
> >            y[0] = p_lat * ProjApi.Proj.DEG_TO_RAD;
> >            x[0] = p_lon * ProjApi.Proj.DEG_TO_RAD;
> > z[0] = 0.0;
> >            IntPtr src0 = ProjApi.Proj.pj_init_plus("+proj=latlong
> > +datum=NAD27");
> >            IntPtr src1 = ProjApi.Proj.pj_init_plus("+proj=latlong
> > +datum=NAD83");
> >            IntPtr dst0 = ProjApi.Proj.pj_init_plus("+proj=utm +zone="
> > + ZoneNumber + " +datum=NAD27");
> >            IntPtr dst1 = ProjApi.Proj.pj_init_plus("+proj=utm +zone="
> > + ZoneNumber + " +datum=NAD83");
> > //This nice little bit of code below is designed to execute
> > pj_transfrom (the proj lib all around function)
> > //with the correct parameters so that a datumshift to the correct
> > datum is included.
> >            try
> >            {
> >                if (datumIn == 0)
> >                {
> >                    if (datumOut == 0)
> >                    {
> >                        errno = ProjApi.Proj.pj_transform(src0, dst0,
> > 1, 1, x, y, z);//NAD27-NAD83
> >                    }
> >                    else
> >                    {
> >                        errno = ProjApi.Proj.pj_transform(src0, dst1,
> > 1, 1, x, y, z);//NAD27-NAD27
> >                    }
> >                }
> >                else
> >                {
> >                    if (datumOut == 0)
> >                    {
> >                        errno = ProjApi.Proj.pj_transform(src1, dst0,
> > 1, 1, x, y, z);//NAD83-NAD27
> >                    }
> >                    else
> >                    {
> >                        errno = ProjApi.Proj.pj_transform(src1, dst1,
> > 1, 1, x, y, z);//NAD83-NAD83
> >                    }
> >                }
> >            }
> >            catch { }
> >
> >            ProjApi.Proj.pj_free(dst1);
> >            ProjApi.Proj.pj_free(src1);
> >            ProjApi.Proj.pj_free(dst0);
> >            ProjApi.Proj.pj_free(src0);
> > UTMNorthing = y[0];
> > UTMEasting = x[0];
> > UTMZone = ZoneNumber;
> > return errno;
> > }
> >
> >
> > Here is the definition and DLL import.
> >        [DllImport("proj.dll", CharSet = CharSet.Ansi,
> > CallingConvention = CallingConvention.Cdecl)]
> >        public static extern unsafe int pj_transform(IntPtr src, IntPtr
> > dst,
> >            int point_count, int point_offset,
> >            [InAttribute, OutAttribute] double[] x,
> >            [InAttribute, OutAttribute] double[] y,
> >            [InAttribute, OutAttribute] double[] z);
> >
> > Any help at all would be useful. I am not able to trigger this error
> > myself so I can't even do trial and error.
> >