mirror of
https://github.com/qpdf/qpdf.git
synced 2024-09-28 21:19:06 +00:00
d71f05ca07
This makes all integer type conversions that have potential data loss explicit with calls that do range checks and raise an exception. After this commit, qpdf builds with no warnings when -Wsign-conversion -Wconversion is used with gcc or clang or when -W3 -Wd4800 is used with MSVC. This significantly reduces the likelihood of potential crashes from bogus integer values. There are some parts of the code that take int when they should take size_t or an offset. Such places would make qpdf not support files with more than 2^31 of something that usually wouldn't be so large. In the event that such a file shows up and is valid, at least qpdf would raise an error in the right spot so the issue could be legitimately addressed rather than failing in some weird way because of a silent overflow condition.
917 lines
23 KiB
C++
917 lines
23 KiB
C++
#include <qpdf/QPDFTokenizer.hh>
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// DO NOT USE ctype -- it is locale dependent for some things, and
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// it's not worth the risk of including it in case it may accidentally
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// be used.
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#include <qpdf/QTC.hh>
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#include <qpdf/QPDFExc.hh>
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#include <qpdf/QUtil.hh>
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#include <qpdf/QPDFObjectHandle.hh>
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#include <qpdf/QIntC.hh>
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#include <stdexcept>
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#include <stdlib.h>
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#include <string.h>
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static bool is_delimiter(char ch)
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{
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return (strchr(" \t\n\v\f\r()<>[]{}/%", ch) != 0);
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}
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class QPDFWordTokenFinder: public InputSource::Finder
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{
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public:
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QPDFWordTokenFinder(PointerHolder<InputSource> is,
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std::string const& str) :
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is(is),
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str(str)
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{
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}
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virtual ~QPDFWordTokenFinder()
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{
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}
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virtual bool check();
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private:
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PointerHolder<InputSource> is;
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std::string str;
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};
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bool
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QPDFWordTokenFinder::check()
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{
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// Find a word token matching the given string, preceded by a
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// delimiter, and followed by a delimiter or EOF.
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QPDFTokenizer tokenizer;
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QPDFTokenizer::Token t = tokenizer.readToken(is, "finder", true);
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qpdf_offset_t pos = is->tell();
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if (! (t == QPDFTokenizer::Token(QPDFTokenizer::tt_word, str)))
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{
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QTC::TC("qpdf", "QPDFTokenizer finder found wrong word");
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return false;
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}
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qpdf_offset_t token_start = is->getLastOffset();
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char next;
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bool next_okay = false;
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if (is->read(&next, 1) == 0)
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{
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QTC::TC("qpdf", "QPDFTokenizer inline image at EOF");
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next_okay = true;
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}
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else
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{
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next_okay = is_delimiter(next);
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}
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is->seek(pos, SEEK_SET);
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if (! next_okay)
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{
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return false;
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}
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if (token_start == 0)
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{
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// Can't actually happen...we never start the search at the
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// beginning of the input.
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return false;
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}
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return true;
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}
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QPDFTokenizer::Members::Members() :
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pound_special_in_name(true),
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allow_eof(false),
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include_ignorable(false)
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{
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reset();
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}
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void
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QPDFTokenizer::Members::reset()
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{
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state = st_top;
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type = tt_bad;
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val = "";
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raw_val = "";
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error_message = "";
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unread_char = false;
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char_to_unread = '\0';
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inline_image_bytes = 0;
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string_depth = 0;
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string_ignoring_newline = false;
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last_char_was_bs = false;
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last_char_was_cr = false;
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}
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QPDFTokenizer::Members::~Members()
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{
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}
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QPDFTokenizer::Token::Token(token_type_e type, std::string const& value) :
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type(type),
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value(value),
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raw_value(value)
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{
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if (type == tt_string)
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{
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raw_value = QPDFObjectHandle::newString(value).unparse();
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}
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else if (type == tt_name)
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{
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raw_value = QPDFObjectHandle::newName(value).unparse();
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}
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}
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QPDFTokenizer::QPDFTokenizer() :
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m(new Members())
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{
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}
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void
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QPDFTokenizer::allowPoundAnywhereInName()
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{
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QTC::TC("qpdf", "QPDFTokenizer allow pound anywhere in name");
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this->m->pound_special_in_name = false;
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}
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void
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QPDFTokenizer::allowEOF()
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{
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this->m->allow_eof = true;
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}
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void
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QPDFTokenizer::includeIgnorable()
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{
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this->m->include_ignorable = true;
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}
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bool
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QPDFTokenizer::isSpace(char ch)
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{
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return ((ch == '\0') || QUtil::is_space(ch));
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}
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bool
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QPDFTokenizer::isDelimiter(char ch)
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{
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return is_delimiter(ch);
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}
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void
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QPDFTokenizer::resolveLiteral()
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{
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if ((this->m->val.length() > 0) && (this->m->val.at(0) == '/'))
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{
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this->m->type = tt_name;
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// Deal with # in name token. Note: '/' by itself is a
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// valid name, so don't strip leading /. That way we
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// don't have to deal with the empty string as a name.
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std::string nval = "/";
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char const* valstr = this->m->val.c_str() + 1;
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for (char const* p = valstr; *p; ++p)
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{
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if ((*p == '#') && this->m->pound_special_in_name)
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{
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if (p[1] && p[2] &&
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QUtil::is_hex_digit(p[1]) && QUtil::is_hex_digit(p[2]))
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{
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char num[3];
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num[0] = p[1];
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num[1] = p[2];
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num[2] = '\0';
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char ch = static_cast<char>(strtol(num, 0, 16));
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if (ch == '\0')
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{
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this->m->type = tt_bad;
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QTC::TC("qpdf", "QPDFTokenizer null in name");
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this->m->error_message =
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"null character not allowed in name token";
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nval += "#00";
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}
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else
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{
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nval += ch;
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}
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p += 2;
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}
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else
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{
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QTC::TC("qpdf", "QPDFTokenizer bad name");
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this->m->type = tt_bad;
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this->m->error_message = "invalid name token";
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nval += *p;
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}
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}
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else
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{
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nval += *p;
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}
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}
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this->m->val = nval;
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}
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else if (QUtil::is_number(this->m->val.c_str()))
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{
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if (this->m->val.find('.') != std::string::npos)
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{
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this->m->type = tt_real;
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}
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else
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{
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this->m->type = tt_integer;
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}
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}
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else if ((this->m->val == "true") || (this->m->val == "false"))
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{
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this->m->type = tt_bool;
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}
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else if (this->m->val == "null")
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{
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this->m->type = tt_null;
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}
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else
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{
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// I don't really know what it is, so leave it as tt_word.
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// Lots of cases ($, #, etc.) other than actual words fall
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// into this category, but that's okay at least for now.
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this->m->type = tt_word;
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}
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}
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void
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QPDFTokenizer::presentCharacter(char ch)
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{
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if (this->m->state == st_token_ready)
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{
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throw std::logic_error(
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"INTERNAL ERROR: QPDF tokenizer presented character "
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"while token is waiting");
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}
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char orig_ch = ch;
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// State machine is implemented such that some characters may be
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// handled more than once. This happens whenever you have to use
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// the character that caused a state change in the new state.
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bool handled = true;
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if (this->m->state == st_top)
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{
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// Note: we specifically do not use ctype here. It is
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// locale-dependent.
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if (isSpace(ch))
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{
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if (this->m->include_ignorable)
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{
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this->m->state = st_in_space;
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this->m->val += ch;
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}
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}
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else if (ch == '%')
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{
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this->m->state = st_in_comment;
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if (this->m->include_ignorable)
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{
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this->m->val += ch;
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}
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}
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else if (ch == '(')
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{
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this->m->string_depth = 1;
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this->m->string_ignoring_newline = false;
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memset(this->m->bs_num_register, '\0',
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sizeof(this->m->bs_num_register));
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this->m->last_char_was_bs = false;
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this->m->last_char_was_cr = false;
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this->m->state = st_in_string;
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}
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else if (ch == '<')
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{
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this->m->state = st_lt;
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}
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else if (ch == '>')
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{
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this->m->state = st_gt;
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}
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else
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{
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this->m->val += ch;
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if (ch == ')')
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{
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this->m->type = tt_bad;
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QTC::TC("qpdf", "QPDFTokenizer bad )");
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this->m->error_message = "unexpected )";
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this->m->state = st_token_ready;
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}
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else if (ch == '[')
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{
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this->m->type = tt_array_open;
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this->m->state = st_token_ready;
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}
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else if (ch == ']')
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{
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this->m->type = tt_array_close;
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this->m->state = st_token_ready;
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}
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else if (ch == '{')
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{
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this->m->type = tt_brace_open;
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this->m->state = st_token_ready;
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}
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else if (ch == '}')
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{
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this->m->type = tt_brace_close;
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this->m->state = st_token_ready;
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}
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else
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{
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this->m->state = st_literal;
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}
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}
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}
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else if (this->m->state == st_in_space)
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{
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// We only enter this state if include_ignorable is true.
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if (! isSpace(ch))
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{
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this->m->type = tt_space;
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this->m->unread_char = true;
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this->m->char_to_unread = ch;
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this->m->state = st_token_ready;
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}
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else
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{
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this->m->val += ch;
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}
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}
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else if (this->m->state == st_in_comment)
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{
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if ((ch == '\r') || (ch == '\n'))
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{
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if (this->m->include_ignorable)
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{
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this->m->type = tt_comment;
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this->m->unread_char = true;
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this->m->char_to_unread = ch;
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this->m->state = st_token_ready;
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}
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else
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{
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this->m->state = st_top;
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}
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}
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else if (this->m->include_ignorable)
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{
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this->m->val += ch;
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}
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}
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else if (this->m->state == st_lt)
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{
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if (ch == '<')
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{
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this->m->val = "<<";
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this->m->type = tt_dict_open;
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this->m->state = st_token_ready;
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}
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else
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{
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handled = false;
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this->m->state = st_in_hexstring;
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}
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}
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else if (this->m->state == st_gt)
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{
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if (ch == '>')
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{
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this->m->val = ">>";
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this->m->type = tt_dict_close;
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this->m->state = st_token_ready;
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}
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else
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{
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this->m->val = ">";
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this->m->type = tt_bad;
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QTC::TC("qpdf", "QPDFTokenizer bad >");
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this->m->error_message = "unexpected >";
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this->m->unread_char = true;
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this->m->char_to_unread = ch;
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this->m->state = st_token_ready;
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}
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}
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else if (this->m->state == st_in_string)
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{
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if (this->m->string_ignoring_newline && (ch != '\n'))
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{
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this->m->string_ignoring_newline = false;
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}
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size_t bs_num_count = strlen(this->m->bs_num_register);
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bool ch_is_octal = ((ch >= '0') && (ch <= '7'));
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if ((bs_num_count == 3) || ((bs_num_count > 0) && (! ch_is_octal)))
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{
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// We've accumulated \ddd. PDF Spec says to ignore
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// high-order overflow.
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this->m->val += static_cast<char>(
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strtol(this->m->bs_num_register, 0, 8));
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memset(this->m->bs_num_register, '\0',
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sizeof(this->m->bs_num_register));
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bs_num_count = 0;
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}
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if (this->m->string_ignoring_newline && (ch == '\n'))
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{
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// ignore
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this->m->string_ignoring_newline = false;
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}
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else if (ch_is_octal &&
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(this->m->last_char_was_bs || (bs_num_count > 0)))
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{
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this->m->bs_num_register[bs_num_count++] = ch;
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}
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else if (this->m->last_char_was_bs)
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{
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switch (ch)
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{
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case 'n':
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this->m->val += '\n';
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break;
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case 'r':
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this->m->val += '\r';
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break;
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case 't':
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this->m->val += '\t';
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break;
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case 'b':
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this->m->val += '\b';
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break;
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case 'f':
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this->m->val += '\f';
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break;
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case '\n':
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break;
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case '\r':
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this->m->string_ignoring_newline = true;
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break;
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default:
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// PDF spec says backslash is ignored before anything else
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this->m->val += ch;
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break;
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}
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}
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else if (ch == '\\')
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{
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// last_char_was_bs is set/cleared below as appropriate
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if (bs_num_count)
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{
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throw std::logic_error(
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"INTERNAL ERROR: QPDFTokenizer: bs_num_count != 0 "
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"when ch == '\\'");
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}
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}
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else if (ch == '(')
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{
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this->m->val += ch;
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++this->m->string_depth;
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}
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else if ((ch == ')') && (--this->m->string_depth == 0))
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{
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this->m->type = tt_string;
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this->m->state = st_token_ready;
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}
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else if (ch == '\r')
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{
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// CR by itself is converted to LF
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this->m->val += '\n';
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}
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else if (ch == '\n')
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{
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// CR LF is converted to LF
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if (! this->m->last_char_was_cr)
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{
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this->m->val += ch;
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}
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}
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else
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{
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this->m->val += ch;
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}
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this->m->last_char_was_cr =
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((! this->m->string_ignoring_newline) && (ch == '\r'));
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this->m->last_char_was_bs =
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((! this->m->last_char_was_bs) && (ch == '\\'));
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}
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else if (this->m->state == st_literal)
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{
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if (isDelimiter(ch))
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{
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// A C-locale whitespace character or delimiter terminates
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// token. It is important to unread the whitespace
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// character even though it is ignored since it may be the
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// newline after a stream keyword. Removing it here could
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// make the stream-reading code break on some files,
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// though not on any files in the test suite as of this
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// writing.
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this->m->type = tt_word;
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this->m->unread_char = true;
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this->m->char_to_unread = ch;
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this->m->state = st_token_ready;
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}
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else
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{
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this->m->val += ch;
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}
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}
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else if (this->m->state == st_inline_image)
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{
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this->m->val += ch;
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size_t len = this->m->val.length();
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if (len == this->m->inline_image_bytes)
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{
|
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QTC::TC("qpdf", "QPDFTokenizer found EI by byte count");
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this->m->type = tt_inline_image;
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this->m->inline_image_bytes = 0;
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this->m->state = st_token_ready;
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}
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else if ((this->m->inline_image_bytes == 0) &&
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(len >= 4) &&
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isDelimiter(this->m->val.at(len-4)) &&
|
|
(this->m->val.at(len-3) == 'E') &&
|
|
(this->m->val.at(len-2) == 'I') &&
|
|
isDelimiter(this->m->val.at(len-1)))
|
|
{
|
|
QTC::TC("qpdf", "QPDFTokenizer found EI the old way");
|
|
this->m->val.erase(len - 1);
|
|
this->m->type = tt_inline_image;
|
|
this->m->unread_char = true;
|
|
this->m->char_to_unread = ch;
|
|
this->m->state = st_token_ready;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
handled = false;
|
|
}
|
|
|
|
if (handled)
|
|
{
|
|
// okay
|
|
}
|
|
else if (this->m->state == st_in_hexstring)
|
|
{
|
|
if (ch == '>')
|
|
{
|
|
this->m->type = tt_string;
|
|
this->m->state = st_token_ready;
|
|
if (this->m->val.length() % 2)
|
|
{
|
|
// PDF spec says odd hexstrings have implicit
|
|
// trailing 0.
|
|
this->m->val += '0';
|
|
}
|
|
char num[3];
|
|
num[2] = '\0';
|
|
std::string nval;
|
|
for (unsigned int i = 0; i < this->m->val.length(); i += 2)
|
|
{
|
|
num[0] = this->m->val.at(i);
|
|
num[1] = this->m->val.at(i+1);
|
|
char nch = static_cast<char>(strtol(num, 0, 16));
|
|
nval += nch;
|
|
}
|
|
this->m->val = nval;
|
|
}
|
|
else if (QUtil::is_hex_digit(ch))
|
|
{
|
|
this->m->val += ch;
|
|
}
|
|
else if (isSpace(ch))
|
|
{
|
|
// ignore
|
|
}
|
|
else
|
|
{
|
|
this->m->type = tt_bad;
|
|
QTC::TC("qpdf", "QPDFTokenizer bad hexstring character");
|
|
this->m->error_message = std::string("invalid character (") +
|
|
ch + ") in hexstring";
|
|
this->m->state = st_token_ready;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
throw std::logic_error(
|
|
"INTERNAL ERROR: invalid state while reading token");
|
|
}
|
|
|
|
if ((this->m->state == st_token_ready) && (this->m->type == tt_word))
|
|
{
|
|
resolveLiteral();
|
|
}
|
|
|
|
if (! (betweenTokens() ||
|
|
((this->m->state == st_token_ready) && this->m->unread_char)))
|
|
{
|
|
this->m->raw_val += orig_ch;
|
|
}
|
|
}
|
|
|
|
void
|
|
QPDFTokenizer::presentEOF()
|
|
{
|
|
if (this->m->state == st_inline_image)
|
|
{
|
|
size_t len = this->m->val.length();
|
|
if ((len >= 3) &&
|
|
isDelimiter(this->m->val.at(len-3)) &&
|
|
(this->m->val.at(len-2) == 'E') &&
|
|
(this->m->val.at(len-1) == 'I'))
|
|
{
|
|
QTC::TC("qpdf", "QPDFTokenizer inline image at EOF the old way");
|
|
this->m->type = tt_inline_image;
|
|
this->m->state = st_token_ready;
|
|
}
|
|
}
|
|
|
|
if (this->m->state == st_literal)
|
|
{
|
|
QTC::TC("qpdf", "QPDFTokenizer EOF reading appendable token");
|
|
resolveLiteral();
|
|
}
|
|
else if ((this->m->include_ignorable) && (this->m->state == st_in_space))
|
|
{
|
|
this->m->type = tt_space;
|
|
}
|
|
else if ((this->m->include_ignorable) && (this->m->state == st_in_comment))
|
|
{
|
|
this->m->type = tt_comment;
|
|
}
|
|
else if (betweenTokens())
|
|
{
|
|
this->m->type = tt_eof;
|
|
}
|
|
else if (this->m->state != st_token_ready)
|
|
{
|
|
QTC::TC("qpdf", "QPDFTokenizer EOF reading token");
|
|
this->m->type = tt_bad;
|
|
this->m->error_message = "EOF while reading token";
|
|
}
|
|
|
|
this->m->state = st_token_ready;
|
|
}
|
|
|
|
void
|
|
QPDFTokenizer::expectInlineImage()
|
|
{
|
|
expectInlineImage(PointerHolder<InputSource>());
|
|
}
|
|
|
|
void
|
|
QPDFTokenizer::expectInlineImage(PointerHolder<InputSource> input)
|
|
{
|
|
if (this->m->state != st_top)
|
|
{
|
|
throw std::logic_error("QPDFTokenizer::expectInlineImage called"
|
|
" when tokenizer is in improper state");
|
|
}
|
|
findEI(input);
|
|
this->m->state = st_inline_image;
|
|
}
|
|
|
|
void
|
|
QPDFTokenizer::findEI(PointerHolder<InputSource> input)
|
|
{
|
|
if (! input.getPointer())
|
|
{
|
|
return;
|
|
}
|
|
|
|
qpdf_offset_t last_offset = input->getLastOffset();
|
|
qpdf_offset_t pos = input->tell();
|
|
|
|
// Use QPDFWordTokenFinder to find EI surrounded by delimiters.
|
|
// Then read the next several tokens or up to EOF. If we find any
|
|
// suspicious-looking or tokens, this is probably still part of
|
|
// the image data, so keep looking for EI. Stop at the first EI
|
|
// that passes. If we get to the end without finding one, return
|
|
// the last EI we found. Store the number of bytes expected in the
|
|
// inline image including the EI and use that to break out of
|
|
// inline image, falling back to the old method if needed.
|
|
|
|
bool okay = false;
|
|
bool first_try = true;
|
|
while (! okay)
|
|
{
|
|
QPDFWordTokenFinder f(input, "EI");
|
|
if (! input->findFirst("EI", input->tell(), 0, f))
|
|
{
|
|
break;
|
|
}
|
|
this->m->inline_image_bytes = QIntC::to_size(input->tell() - pos - 2);
|
|
|
|
QPDFTokenizer check;
|
|
bool found_bad = false;
|
|
// Look at the next 10 tokens or up to EOF. The next inline
|
|
// image's image data would look like bad tokens, but there
|
|
// will always be at least 10 tokens between one inline
|
|
// image's EI and the next valid one's ID since width, height,
|
|
// bits per pixel, and color space are all required as well as
|
|
// a BI and ID. If we get 10 good tokens in a row or hit EOF,
|
|
// we can be pretty sure we've found the actual EI.
|
|
for (int i = 0; i < 10; ++i)
|
|
{
|
|
QPDFTokenizer::Token t =
|
|
check.readToken(input, "checker", true);
|
|
token_type_e type = t.getType();
|
|
if (type == tt_eof)
|
|
{
|
|
okay = true;
|
|
}
|
|
else if (type == tt_bad)
|
|
{
|
|
found_bad = true;
|
|
}
|
|
else if (type == tt_word)
|
|
{
|
|
// The qpdf tokenizer lumps alphabetic and otherwise
|
|
// uncategorized characters into "words". We recognize
|
|
// strings of alphabetic characters as potential valid
|
|
// operators for purposes of telling whether we're in
|
|
// valid content or not. It's not perfect, but it
|
|
// should work more reliably than what we used to do,
|
|
// which was already good enough for the vast majority
|
|
// of files.
|
|
bool found_alpha = false;
|
|
bool found_non_printable = false;
|
|
bool found_other = false;
|
|
std::string value = t.getValue();
|
|
for (std::string::iterator iter = value.begin();
|
|
iter != value.end(); ++iter)
|
|
{
|
|
char ch = *iter;
|
|
if (((ch >= 'a') && (ch <= 'z')) ||
|
|
((ch >= 'A') && (ch <= 'Z')) ||
|
|
(ch == '*'))
|
|
{
|
|
// Treat '*' as alpha since there are valid
|
|
// PDF operators that contain * along with
|
|
// alphabetic characters.
|
|
found_alpha = true;
|
|
}
|
|
else if (((ch < 32) && (! isSpace(ch))) || (ch > 127))
|
|
{
|
|
found_non_printable = true;
|
|
break;
|
|
}
|
|
else
|
|
{
|
|
found_other = true;
|
|
}
|
|
}
|
|
if (found_non_printable || (found_alpha && found_other))
|
|
{
|
|
found_bad = true;
|
|
}
|
|
}
|
|
if (okay || found_bad)
|
|
{
|
|
break;
|
|
}
|
|
}
|
|
if (! found_bad)
|
|
{
|
|
okay = true;
|
|
}
|
|
if (! okay)
|
|
{
|
|
first_try = false;
|
|
}
|
|
}
|
|
if (okay && (! first_try))
|
|
{
|
|
QTC::TC("qpdf", "QPDFTokenizer found EI after more than one try");
|
|
}
|
|
|
|
input->seek(pos, SEEK_SET);
|
|
input->setLastOffset(last_offset);
|
|
}
|
|
|
|
bool
|
|
QPDFTokenizer::getToken(Token& token, bool& unread_char, char& ch)
|
|
{
|
|
bool ready = (this->m->state == st_token_ready);
|
|
unread_char = this->m->unread_char;
|
|
ch = this->m->char_to_unread;
|
|
if (ready)
|
|
{
|
|
if (this->m->type == tt_bad)
|
|
{
|
|
this->m->val = this->m->raw_val;
|
|
}
|
|
token = Token(this->m->type, this->m->val,
|
|
this->m->raw_val, this->m->error_message);
|
|
this->m->reset();
|
|
}
|
|
return ready;
|
|
}
|
|
|
|
bool
|
|
QPDFTokenizer::betweenTokens()
|
|
{
|
|
return ((this->m->state == st_top) ||
|
|
((! this->m->include_ignorable) &&
|
|
((this->m->state == st_in_comment) ||
|
|
(this->m->state == st_in_space))));
|
|
}
|
|
|
|
QPDFTokenizer::Token
|
|
QPDFTokenizer::readToken(PointerHolder<InputSource> input,
|
|
std::string const& context,
|
|
bool allow_bad,
|
|
size_t max_len)
|
|
{
|
|
qpdf_offset_t offset = input->tell();
|
|
Token token;
|
|
bool unread_char;
|
|
char char_to_unread;
|
|
bool presented_eof = false;
|
|
while (! getToken(token, unread_char, char_to_unread))
|
|
{
|
|
char ch;
|
|
if (input->read(&ch, 1) == 0)
|
|
{
|
|
if (! presented_eof)
|
|
{
|
|
presentEOF();
|
|
presented_eof = true;
|
|
if ((this->m->type == tt_eof) && (! this->m->allow_eof))
|
|
{
|
|
// Nothing in the qpdf library calls readToken
|
|
// without allowEOF anymore, so this case is not
|
|
// exercised.
|
|
this->m->type = tt_bad;
|
|
this->m->error_message = "unexpected EOF";
|
|
offset = input->getLastOffset();
|
|
}
|
|
}
|
|
else
|
|
{
|
|
throw std::logic_error(
|
|
"getToken returned false after presenting EOF");
|
|
}
|
|
}
|
|
else
|
|
{
|
|
presentCharacter(ch);
|
|
if (betweenTokens() && (input->getLastOffset() == offset))
|
|
{
|
|
++offset;
|
|
}
|
|
if (max_len && (this->m->raw_val.length() >= max_len) &&
|
|
(this->m->state != st_token_ready))
|
|
{
|
|
// terminate this token now
|
|
QTC::TC("qpdf", "QPDFTokenizer block long token");
|
|
this->m->type = tt_bad;
|
|
this->m->state = st_token_ready;
|
|
this->m->error_message =
|
|
"exceeded allowable length while reading token";
|
|
}
|
|
}
|
|
}
|
|
|
|
if (unread_char)
|
|
{
|
|
input->unreadCh(char_to_unread);
|
|
}
|
|
|
|
if (token.getType() != tt_eof)
|
|
{
|
|
input->setLastOffset(offset);
|
|
}
|
|
|
|
if (token.getType() == tt_bad)
|
|
{
|
|
if (allow_bad)
|
|
{
|
|
QTC::TC("qpdf", "QPDFTokenizer allowing bad token");
|
|
}
|
|
else
|
|
{
|
|
throw QPDFExc(qpdf_e_damaged_pdf, input->getName(),
|
|
context, offset, token.getErrorMessage());
|
|
}
|
|
}
|
|
|
|
return token;
|
|
}
|