hash.m

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function hashVec=hash(inpArr,methodName)
if nargin<2
    methodName='SHA-1';
end
switch (class(inpArr))
    case 'struct'
        hashVec=structhash(inpArr,methodName);
    case 'cell'
        hashVec=cellhash(inpArr,methodName);
    otherwise
        if ~isempty(inpArr)
            hashVec=hashinner(inpArr,methodName);
        else
            hashVec=hashinner('valueisemptynohash',methodName);
        end
end
end
%
function hashVec=structhash(structB,methodName)
fieldNames=fieldnames(structB);
hashMat=mxberry.core.hash(...
    [{'itisastruct';num2str(size(structB))};fieldNames],methodName);
%
hashMat=[hashMat;cellhash(struct2cell(structB),methodName)];
hashVec=mxberry.core.hash(hashMat,methodName);
end
%
function hashVec=cellhash(cellB,methodName)
import mxberry.core.hash;
%
hashCell=cellfun(@(x)hash(x,methodName),cellB,'UniformOutput',false);
hashCell=reshape(hashCell,[],1);
hashMat=cell2mat(hashCell);
hashMat=[hash(['itisacell' num2str(size(cellB))]);hashMat];
hashVec=hash(hashMat,methodName);
end

function h = hashinner(inpArr,meth)

inpVec=inpArr(:);
% convert strings and logicals into uint8 format
if ischar(inpVec) || islogical(inpVec)
    byteVec=uint8(inpVec);
else % convert everything else into uint8 format without loss of data
    if isnumeric(inpVec)&&isreal(inpVec)
        byteVec=typecast(inpVec,'uint8');
    else
        byteVec=getByteStreamFromArray(inpArr);
    end
end

% verify hash method, with some syntactical forgiveness:
meth=upper(meth);
switch meth
    case 'SHA1'
        meth='SHA-1';
    case 'SHA256'
        meth='SHA-256';
    case 'SHA384'
        meth='SHA-384';
    case 'SHA512'
        meth='SHA-512';
    otherwise
end
algs={'MD2','MD5','SHA-1','SHA-256','SHA-384','SHA-512'};
if isempty(strcmp(meth,algs))
    mxberry.core.throwerror('wrongInput',['Hash algorithm must be ' ...
        'MD2, MD5, SHA-1, SHA-256, SHA-384, or SHA-512']);
end
% create hash
x=java.security.MessageDigest.getInstance(meth);
x.update(byteVec);
h=typecast(x.digest,'uint8');
h=dec2hex(h)';
if(size(h,1))==1 % remote possibility: all hash bytes < 128, so pad:
    h=[repmat('0',[1 size(h,2)]);h];
end
h=lower(h(:)');
clear x
end