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DcmCharString: add some support for multi-byte characters #124

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45 changes: 34 additions & 11 deletions dcmdata/include/dcmtk/dcmdata/dcbytstr.h
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Original file line number Diff line number Diff line change
Expand Up @@ -274,20 +274,19 @@ class DCMTK_DCMDATA_EXPORT DcmByteString: public DcmElement
*/
virtual OFCondition verify(const OFBool autocorrect = OFFalse);

/** check if this element contains non-ASCII characters. Please note that this check
* is pretty simple and only works for single-byte character sets that do include
* the 7-bit ASCII codes, e.g. for the ISO 8859 family. In other words: All character
* codes below 128 are considered to be ASCII codes and all others are considered to
* be non-ASCII.
/** check if this element contains non-ASCII characters.
* This works by checking for any byte values above 127, which works for any
* single-byte code and for single-value multi-byte codes, and for ESC characters,
* which will mean that a code extension is used.
* @param checkAllStrings if true, also check elements with string values not affected
* by SpecificCharacterSet (0008,0005). By default, only check PN, LO, LT, SH, ST,
* UC and UT, i.e. none of the derived VR classes.
* UC and UT.
* @return true if element contains non-ASCII characters, false otherwise
*/
virtual OFBool containsExtendedCharacters(const OFBool checkAllStrings = OFFalse);

/** check if this element is affected by SpecificCharacterSet
* @return always returns false since none of the derived VR classes is affected by
* @return returns false, overwritten by derived VR classes that are affected by
* the SpecificCharacterSet (0008,0005) element
*/
virtual OFBool isAffectedBySpecificCharacterSet() const;
Expand Down Expand Up @@ -379,6 +378,20 @@ class DCMTK_DCMDATA_EXPORT DcmByteString: public DcmElement
*/
virtual OFCondition makeMachineByteString(const Uint32 length = 0);

/** check if the VR supports more than one value.
* @return OFTrue
*/
virtual OFBool supportsMultiValue() const { return OFTrue; }

/** find the start index of the next component.
* @param str pointer to the string value to be searched
* @param len the length of @a str
* @param start the start character index for the search
* @param charSet the value of Specific Character Set; not used
* @return the index of the next value, or OFString_npos if none exists.
*/
virtual size_t findNextValuePosition(const char* str, size_t len, size_t start, const OFString& charSet) const;

/** convert currently stored string value to DICOM representation.
* It removes trailing spaces apart from a possibly required single padding
* character (in case of odd string length).
Expand Down Expand Up @@ -418,13 +431,23 @@ class DCMTK_DCMDATA_EXPORT DcmByteString: public DcmElement
*/
void setNonSignificantChars(const OFString &characters) { nonSignificantChars = characters; }

/** set element value at a specific value position in the given character string,
* considering the specific character set for finding the position, if given.
* @param stringVal input character string (possibly multi-valued)
* @param pos position (0..vm) where the value should be inserted
* @param charSet the value of the Specific Character Set
* @return status, EC_Normal if successful, an error code otherwise
*/
OFCondition putOFStringAtPosWithCharset(const OFString& stringVal,
const unsigned long pos,
const OFString& charSet);

/* --- static helper functions --- */

/** check if a given character string contains non-ASCII characters.
* Please note that this check is pretty simple and only works for single-byte character
* sets that do include the 7-bit ASCII codes, e.g. for the ISO 8859 family. In other
* words: All character codes below 128 are considered to be ASCII codes and all others
* are considered to be non-ASCII.
* This works by checking for any byte values above 127, which works for any
* single-byte code and for single-value multi-byte codes, and for ESC characters,
* which will mean that a code extension is used.
* @param stringVal character string to be checked
* @param stringLen length of the string (number of characters without the trailing
* NULL byte)
Expand Down
41 changes: 32 additions & 9 deletions dcmdata/include/dcmtk/dcmdata/dcchrstr.h
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Original file line number Diff line number Diff line change
Expand Up @@ -107,17 +107,31 @@ class DCMTK_DCMDATA_EXPORT DcmCharString
*/
virtual OFCondition verify(const OFBool autocorrect = OFFalse);

/** check if this element contains non-ASCII characters. Please note that this check
* is pretty simple and only works for single-byte character sets that do include
* the 7-bit ASCII codes, e.g. for the ISO 8859 family. In other words: All character
* codes below 128 are considered to be ASCII codes and all others are considered to
* be non-ASCII.
* @param checkAllStrings not used in this class
* @return true if element contains non-ASCII characters, false otherwise
/** get value multiplicity
* @return number of string components (separated by a backslash)
*/
virtual OFBool containsExtendedCharacters(const OFBool checkAllStrings = OFFalse);
virtual unsigned long getVM();

/** check if this element is affected by SpecificCharacterSet
/** get a copy of a particular string component
* @param stringVal variable in which the result value is stored
* @param pos index of the value in case of multi-valued elements (0..vm-1)
* @param normalize not used since string normalization depends on value representation
* @return status, EC_Normal if successful, an error code otherwise
*/
virtual OFCondition getOFString(OFString &stringVal,
const unsigned long pos,
OFBool normalize = OFTrue);


/** set element value at specific VM position in the given character string.
* @param stringVal input character string (possibly multi-valued)
* @param pos position (0..vm) where the value should be inserted
* @return status, EC_Normal if successful, an error code otherwise
*/
virtual OFCondition putOFStringAtPos(const OFString& stringVal,
const unsigned long pos = 0);

/** check if this element is affected by SpecificCharacterSet
* @return always returns true since all derived VR classes are affected by the
* SpecificCharacterSet (0008,0005) element
*/
Expand Down Expand Up @@ -169,6 +183,15 @@ class DCMTK_DCMDATA_EXPORT DcmCharString
*/
virtual const OFString& getDelimiterChars() const;

/** find the start index of the next value in a multi-valued attribute.
* @param str pointer to the string value to be searched
* @param len the length of @a str
* @param start the start character index for the search
* @param charSet the value of Specific Character Set; if not set, single-byte encoding is assumed
* @return the index of the next value, or OFString_npos if none exists.
*/
virtual size_t findNextValuePosition(const char* str, size_t len, size_t start, const OFString& charSet) const;

};


Expand Down
9 changes: 4 additions & 5 deletions dcmdata/include/dcmtk/dcmdata/dcitem.h
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Original file line number Diff line number Diff line change
Expand Up @@ -317,11 +317,10 @@ class DCMTK_DCMDATA_EXPORT DcmItem
*/
virtual OFBool containsUnknownVR() const;

/** check if this object contains non-ASCII characters at any nesting level. Please note
* that this check is pretty simple and only works for single-byte character sets that
* do include the 7-bit ASCII codes, e.g. for the ISO 8859 family. In other words: All
* character codes below 128 are considered to be ASCII codes and all others are
* considered to be non-ASCII.
/** check if this object contains non-ASCII characters.
* This works by checking for any byte values above 127, which works for any
* single-byte code and for single-value multi-byte codes, and for ESC characters,
* which will mean that a code extension is used.
* @param checkAllStrings if true, also check elements with string values not affected
* by SpecificCharacterSet (0008,0005). By default, only check PN, LO, LT, SH, ST,
* UC and UT.
Expand Down
9 changes: 4 additions & 5 deletions dcmdata/include/dcmtk/dcmdata/dcsequen.h
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Original file line number Diff line number Diff line change
Expand Up @@ -313,11 +313,10 @@ class DCMTK_DCMDATA_EXPORT DcmSequenceOfItems : public DcmElement
*/
virtual OFBool containsUnknownVR() const;

/** check if this object contains non-ASCII characters at any nesting level. Please note
* that this check is pretty simple and only works for single-byte character sets that
* do include the 7-bit ASCII codes, e.g. for the ISO 8859 family. In other words: All
* character codes below 128 are considered to be ASCII codes and all others are
* considered to be non-ASCII.
/** check if this object contains non-ASCII characters.
* This works by checking for any byte values above 127, which works for any
* single-byte code and for single-value multi-byte codes, and for ESC characters,
* which will mean that a code extension is used.
* @param checkAllStrings if true, also check elements with string values not affected
* by SpecificCharacterSet (0008,0005). By default, only check PN, LO, LT, SH, ST,
* UC and UT.
Expand Down
15 changes: 8 additions & 7 deletions dcmdata/include/dcmtk/dcmdata/dcvrlt.h
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Expand Up @@ -114,13 +114,6 @@ class DCMTK_DCMDATA_EXPORT DcmLongText
virtual OFCondition checkValue(const OFString &vm = "",
const OFBool oldFormat = OFFalse);

/** get the value multiplicity.
* Since the backslash "\" is not regarded as a separator the value
* multiplicity is always 1.
* @return value multiplicity of the currently stored value
*/
virtual unsigned long getVM();

/** get a copy of a particular string component
* @param stringVal variable in which the result value is stored
* @param pos index of the value in case of multi-valued elements (0..vm-1)
Expand Down Expand Up @@ -151,6 +144,14 @@ class DCMTK_DCMDATA_EXPORT DcmLongText
*/
static OFCondition checkStringValue(const OFString &value,
const OFString &charset = "");

protected:
/** check if the VR supports more than one value.
* Since the backslash "\" is not regarded as a separator,
* multiple values cannot be encoded.
* @return OFFalse
*/
virtual OFBool supportsMultiValue() const { return OFFalse; };
};


Expand Down
14 changes: 7 additions & 7 deletions dcmdata/include/dcmtk/dcmdata/dcvrst.h
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Expand Up @@ -115,13 +115,6 @@ class DCMTK_DCMDATA_EXPORT DcmShortText
virtual OFCondition checkValue(const OFString &vm = "",
const OFBool oldFormat = OFFalse);

/** get the value multiplicity.
* Since the backslash "\" is not regarded as a separator the value
* multiplicity is always 1.
* @return value multiplicity of the currently stored value
*/
virtual unsigned long getVM();

/** get a copy of a particular string component
* @param stringVal variable in which the result value is stored
* @param pos index of the value in case of multi-valued elements (0..vm-1)
Expand Down Expand Up @@ -152,6 +145,13 @@ class DCMTK_DCMDATA_EXPORT DcmShortText
*/
static OFCondition checkStringValue(const OFString &value,
const OFString &charset = "");
protected:
/** check if the VR supports more than one value.
* Since the backslash "\" is not regarded as a separator,
* multiple values cannot be encoded.
* @return OFFalse
*/
virtual OFBool supportsMultiValue() const { return OFFalse; };
};


Expand Down
14 changes: 7 additions & 7 deletions dcmdata/include/dcmtk/dcmdata/dcvrut.h
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Expand Up @@ -117,13 +117,6 @@ class DCMTK_DCMDATA_EXPORT DcmUnlimitedText
virtual OFCondition checkValue(const OFString &vm = "",
const OFBool oldFormat = OFFalse);

/** get the value multiplicity.
* Since the backslash "\" is not regarded as a separator the value
* multiplicity is always 1.
* @return value multiplicity of the currently stored value
*/
virtual unsigned long getVM();

/** get a copy of a particular string component
* @param stringVal variable in which the result value is stored
* @param pos index of the value in case of multi-valued elements (0..vm-1)
Expand Down Expand Up @@ -154,6 +147,13 @@ class DCMTK_DCMDATA_EXPORT DcmUnlimitedText
*/
static OFCondition checkStringValue(const OFString &value,
const OFString &charset = "");
protected:
/** check if the VR supports more than one value.
* Since the backslash "\" is not regarded as a separator,
* multiple values cannot be encoded.
* @return OFFalse
*/
virtual OFBool supportsMultiValue() const { return OFFalse; };
};


Expand Down
55 changes: 36 additions & 19 deletions dcmdata/libsrc/dcbytstr.cc
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Expand Up @@ -467,9 +467,8 @@ OFCondition DcmByteString::putString(const char *stringVal,
return errorFlag;
}


OFCondition DcmByteString::putOFStringAtPos(const OFString& stringVal,
const unsigned long pos)
OFCondition DcmByteString::putOFStringAtPosWithCharset(const OFString& stringVal, const unsigned long pos,
const OFString& charSet)
{
OFCondition result;
// Get old value
Expand Down Expand Up @@ -505,46 +504,42 @@ OFCondition DcmByteString::putOFStringAtPos(const OFString& stringVal,
// First value is set: Replace old value with new value
else
{
rightPos = str.find_first_of('\\', 0);
str = str.replace(0, rightPos, stringVal);
rightPos = findNextValuePosition(str.c_str(), str.length(), 0, charSet);
str = str.replace(0, rightPos - 1, stringVal);
}
return putOFStringArray(str);
}

// 3rd case: New value should be inserted somewhere in the middle
size_t leftPos = 0;
size_t vmPos = 0;
size_t strLen = str.length();
// First, find the correct position, and then insert / replace new value
do
{
// Step from value to value by looking for delimiters.
// Special handling first search (start looking at position 0 instead of 1)
if (vmPos == 0) leftPos = str.find('\\', 0);
else leftPos = str.find('\\', leftPos + 1 );
// leftPos = str.find('\\', leftPos == 0 ? 0 : leftPos +1);
leftPos = findNextValuePosition(str.c_str(), strLen, leftPos, charSet);
if (leftPos != OFString_npos)
{
vmPos++;
}
}
while ( (leftPos != OFString_npos) && (vmPos != pos) );
rightPos = str.find_first_of('\\', leftPos+1);
if (rightPos == OFString_npos) rightPos = str.length();
rightPos = findNextValuePosition(str.c_str(), strLen, leftPos, charSet);
if (rightPos == OFString_npos) rightPos = strLen + 1;

// If we do not have an old value of size 1 or we have an empty value
if (rightPos - leftPos == 1)
{
// Empty value
if (str.at(leftPos) == '\\')
str = str.insert(rightPos, stringVal);
str = str.insert(leftPos, stringVal);
// Old value (length 1)
else
str = str.replace(leftPos, 1, stringVal);
}
// Otherwise replace existing old value (length > 1)
else
{
str = str.replace(leftPos+1, rightPos - leftPos - 1, stringVal);
str = str.replace(leftPos, rightPos - leftPos - 1, stringVal);
}
// Finally re-insert all values include new value
result = putOFStringArray( str );
Expand All @@ -553,6 +548,28 @@ OFCondition DcmByteString::putOFStringAtPos(const OFString& stringVal,
}



OFCondition DcmByteString::putOFStringAtPos(const OFString& stringVal,
const unsigned long pos)
{
return putOFStringAtPosWithCharset(stringVal, pos, "");
}


// ********************************


size_t DcmByteString::findNextValuePosition(const char* str, size_t len, size_t start, const OFString& /*charSet*/) const
{
const char *p = str + start;
for (size_t i = start; i < len; ++i)
{
if (*p++ == '\\')
return i + 1;
}
return OFString_npos;
}

// ********************************


Expand Down Expand Up @@ -770,7 +787,7 @@ OFBool DcmByteString::containsExtendedCharacters(const OFBool checkAllStrings)
OFBool result = OFFalse;
/* only check if parameter is true since derived VRs are not affected
by the attribute SpecificCharacterSet (0008,0005) */
if (checkAllStrings)
if (checkAllStrings || isAffectedBySpecificCharacterSet())
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@mrbean-bremen mrbean-bremen Aug 8, 2025

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this check makes the separate method in DcmCharString obsolete

{
char *str = NULL;
Uint32 len = 0;
Expand Down Expand Up @@ -876,10 +893,10 @@ OFBool DcmByteString::containsExtendedCharacters(const char *stringVal,
{
if (stringVal != NULL)
{
for (size_t i = stringLen; i != 0; --i)
for (size_t i = stringLen; i != 0; --i, ++stringVal)
{
/* check for 8 bit characters */
if (OFstatic_cast(unsigned char, *stringVal++) > 127)
/* check for 8 bit and Escape characters */
if ((*stringVal & 0x80) != 0 || (*stringVal == 0x1b))
return OFTrue;
}
}
Expand Down
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