/// <summary>
///
/// </summary>
/// <param name="bits"></param>
/// <param name="index"></param>
/// <param name="ctx"></param>
/// <returns></returns>
public static GribMessage Create(byte[] bits, int index, GribContext ctx)
{
var buff = Marshal.AllocHGlobal(bits.Length);
Marshal.Copy(bits, 0, buff, bits.Length);
int err = 0;
SizeT sz = (SizeT)bits.Length;
GribMessage msg = null;
GribHandle handle = null;
lock (_fileLock)
{
// grib_api moves to the next message in a stream for each new handle
handle = GribApiProxy.GribHandleNewFromMultiMessage(ctx, out buff, ref sz, out err);
}
if (err != 0)
{
Marshal.AllocHGlobal(buff);
throw GribApiException.Create(err);
}
if (handle != null)
{
msg = new GribMessage(handle, ctx, buff, index);
}
return(msg);
}
internal static void DeleteGribBox(HandleRef box)
{
int ret = _DeleteGribBox(box);
if (ret != 0)
{
throw GribApiException.Create(ret);
}
}
/// <summary>
/// Initializes a new instance of the <see cref="GribBox"/> class.
/// </summary>
/// <param name="msgHandle">The MSG handle.</param>
/// <param name="nw">The nw.</param>
/// <param name="se">The se.</param>
public GribBox(GribHandle msgHandle, GeoCoordinate nw, GeoCoordinate se)
{
int err;
var box = GribApiProxy.GribBoxNew(msgHandle, out err);
if (err != 0)
{
throw GribApiException.Create(err);
}
var pts = GribApiProxy.GribBoxGetPoints(box, nw.Latitude, nw.Longitude, se.Latitude, se.Longitude, out err);
if (err != 0)
{
throw GribApiException.Create(err);
}
_points = new GribPoints(SWIGTYPE_p_grib_points.getCPtr(pts).Handle, false);
}
/// <summary>
/// Creates a GribMessage instance from a <seealso cref="Grib.Api.GribFile"/>.
/// </summary>
/// <param name="file">The file.</param>
/// <param name="index">The index.</param>
/// <returns></returns>
public static GribMessage Create(GribFile file, int index)
{
GribMessage msg = null;
int err = 0;
// grib_api moves to the next message in a stream for each new handle
GribHandle handle = GribApiProxy.GribHandleNewFromFile(file.Context, file, out err);
if (err != 0)
{
throw GribApiException.Create(err);
}
if (handle != null)
{
msg = new GribMessage(handle, file.Context, index);
}
return(msg);
}
/// <summary>
/// Creates a GribMessage instance from a buffer.
/// </summary>
/// <param name="bits"></param>
/// <param name="index"></param>
/// <returns></returns>
public static GribMessage Create(byte[] bits, int index = 0)
{
GCHandle h = GCHandle.Alloc(bits, GCHandleType.Pinned);
IntPtr pHandle = h.AddrOfPinnedObject();
int err = 0;
SizeT sz = (SizeT)bits.Length;
GribHandle handle = GribApiProxy.GribHandleNewFromMultiMessage(GribContext.Default, out pHandle, ref sz, out err);
if (err != 0)
{
h.Free();
throw GribApiException.Create(err);
}
GribMessage msg = null;
if (handle != null)
{
msg = new GribMessage(handle, GribContext.Default, h, index);
}
return(msg);
}
protected GribMessage GetNextMessage(int index)
{
// the starting position of the stream
var streamStartPos = this.Stream.Position;
// if there are headers in the file, the message may not align with the beginning of the stream
// or the end of the previous message.
long msgOffset = 0;
byte[] buffer64 = new byte[8];
byte[] buffer32 = new byte[4];
byte[] buffer24 = new byte[3];
/*
* GRIB Message Octets Content (0 indexed)
* 0-3 'GRIB' (Coded CCITT-ITA No. 5) (ASCII);
* 4-6 GRIB1: Total length of GRIB message (including Section 0)
* 7 Edition number
* 8-15 GRIB2: Total length of GRIB message(including Sections 0 & 5);
*/
bool foundStart = false;
while (this.Stream.Position + 1 < this.Stream.Length && !foundStart)
{
msgOffset = this.Stream.Position;
if (this.Stream.ReadByte() == GRIB_MSG_START[0])
{
this.Stream.Seek(-1, SeekOrigin.Current);
this.Stream.Read(buffer32, 0, 4);
if (buffer32.SequenceEqual(GRIB_MSG_START))
{
foundStart = true;
}
else
{
this.Stream.Seek(msgOffset + 1, SeekOrigin.Begin);
}
}
}
if (!foundStart)
{
return(null);
}
// at this point, the stream should be pointing to the "B" octet in the "GRIB" sequence
// if this is an edition 1, the next 3 bytes are the length of the message
this.Stream.Read(buffer24, 0, 3);
// get the edition number and read the message length per ed spec
var ed = this.Stream.ReadByte();
if (ed == 0)
{
throw GribApiException.Create(-12);
}
else if (ed == 1)
{
buffer32.Initialize();
Array.Copy(buffer24, 0, buffer64, 5, 3);
}
else if (ed == 2)
{
this.Stream.Read(buffer64, 0, 8);
}
if (BitConverter.IsLittleEndian)
{
Array.Reverse(buffer64);
}
long msgLen = BitConverter.ToInt64(buffer64, 0);
long end = msgLen + streamStartPos;
// get the length of the message, including any headers
long totalLen = (msgOffset - streamStartPos) + msgLen;
this.Stream.Seek(streamStartPos, SeekOrigin.Begin);
byte[] msgBytes = new byte[totalLen];
this.Stream.Read(msgBytes, 0, (int)totalLen);
return(GribMessage.Create(msgBytes));
}
