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#include <qpdf/QPDF_String.hh>
#include <qpdf/QUtil.hh>
#include <qpdf/QTC.hh>
// DO NOT USE ctype -- it is locale dependent for some things, and
// it's not worth the risk of including it in case it may accidentally
// be used.
#include <string.h>
// See above about ctype.
static bool is_ascii_printable(unsigned char ch)
{
return ((ch >= 32) && (ch <= 126));
}
static bool is_iso_latin1_printable(unsigned char ch)
{
return (((ch >= 32) && (ch <= 126)) || (ch >= 160));
}
QPDF_String::QPDF_String(std::string const& val) :
val(val)
{
}
QPDF_String::~QPDF_String()
{
}
std::string
QPDF_String::unparse()
{
return unparse(false);
}
std::string
QPDF_String::unparse(bool force_binary)
{
bool use_hexstring = force_binary;
if (! use_hexstring)
{
unsigned int nonprintable = 0;
int consecutive_printable = 0;
for (unsigned int i = 0; i < this->val.length(); ++i)
{
char ch = this->val[i];
// Note: do not use locale to determine printability. The
// PDF specification accepts arbitrary binary data. Some
// locales imply multibyte characters. We'll consider
// something printable if it is printable in 7-bit ASCII.
// We'll code this manually rather than being rude and
// setting locale.
if ((ch == 0) || (! (is_ascii_printable(ch) ||
strchr("\n\r\t\b\f", ch))))
{
++nonprintable;
consecutive_printable = 0;
}
else
{
if (++consecutive_printable > 5)
{
// If there are more than 5 consecutive printable
// characters, I want to see them as such.
nonprintable = 0;
break;
}
}
}
// Use hex notation if more than 20% of the characters are not
// printable in plain ASCII.
if (5 * nonprintable > val.length())
{
use_hexstring = true;
}
}
std::string result;
if (use_hexstring)
{
result += "<";
char num[3];
for (unsigned int i = 0; i < this->val.length(); ++i)
{
sprintf(num, "%02x", (unsigned char) this->val[i]);
result += num;
}
result += ">";
}
else
{
result += "(";
char num[5];
for (unsigned int i = 0; i < this->val.length(); ++i)
{
char ch = this->val[i];
switch (ch)
{
case '\n':
result += "\\n";
break;
case '\r':
result += "\\r";
break;
case '\t':
result += "\\t";
break;
case '\b':
result += "\\b";
break;
case '\f':
result += "\\f";
break;
case '(':
result += "\\(";
break;
case ')':
result += "\\)";
break;
case '\\':
result += "\\\\";
break;
default:
if (is_iso_latin1_printable(ch))
{
result += this->val[i];
}
else
{
sprintf(num, "\\%03o", (unsigned char)ch);
result += num;
}
break;
}
}
result += ")";
}
return result;
}
std::string
QPDF_String::getVal() const
{
return this->val;
}
std::string
QPDF_String::getUTF8Val() const
{
std::string result;
unsigned int len = this->val.length();
if ((len >= 2) && (len % 2 == 0) &&
(this->val[0] == '\xfe') && (this->val[1] == '\xff'))
{
// This is a Unicode string using big-endian UTF-16. This
// code uses unsigned long and unsigned short to hold
// codepoint values. It requires unsigned long to be at least
// 32 bits and unsigned short to be at least 16 bits, but it
// will work fine if they are larger.
unsigned long codepoint = 0L;
for (unsigned int i = 2; i < len; i += 2)
{
// Convert from UTF16-BE. If we get a malformed
// codepoint, this code will generate incorrect output
// without giving a warning. Specifically, a high
// codepoint not followed by a low codepoint will be
// discarded, and a low codepoint not preceded by a high
// codepoint will just get its low 10 bits output.
unsigned short bits =
(((unsigned char) this->val[i]) << 8) +
((unsigned char) this->val[i+1]);
if ((bits & 0xFC00) == 0xD800)
{
codepoint = 0x10000 + ((bits & 0x3FF) << 10);
continue;
}
else if ((bits & 0xFC00) == 0xDC00)
{
if (codepoint != 0)
{
QTC::TC("qpdf", "QPDF_String non-trivial UTF-16");
}
codepoint += bits & 0x3FF;
}
else
{
codepoint = bits;
}
result += QUtil::toUTF8(codepoint);
codepoint = 0;
}
}
else
{
for (unsigned int i = 0; i < len; ++i)
{
result += QUtil::toUTF8((unsigned char) this->val[i]);
}
}
return result;
}
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