From 5b8b1de2dbe272751e8e1c2d40714f857788a846 Mon Sep 17 00:00:00 2001
From: Jakub Melka <Jakub.Melka@seznam.cz>
Date: Fri, 26 Feb 2021 19:21:27 +0100
Subject: [PATCH] Bugfix: Invalid parsing of postscript function

---
 Pdf4QtLib/sources/pdffunction.cpp |  1 +
 Pdf4QtLib/sources/pdfparser.cpp   | 13 ++++++++++++-
 Pdf4QtLib/sources/pdfparser.h     |  4 ++++
 3 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/Pdf4QtLib/sources/pdffunction.cpp b/Pdf4QtLib/sources/pdffunction.cpp
index 341083b..7b6b34d 100644
--- a/Pdf4QtLib/sources/pdffunction.cpp
+++ b/Pdf4QtLib/sources/pdffunction.cpp
@@ -1663,6 +1663,7 @@ PDFPostScriptFunction::Program PDFPostScriptFunction::parseProgram(const QByteAr
 
     Program result;
     PDFLexicalAnalyzer parser(adjustedArray.constBegin(), adjustedArray.constEnd());
+    parser.setTokenizingPostScriptFunction();
 
     std::stack<InstructionPointer> blockCallStack;
     while (true)
diff --git a/Pdf4QtLib/sources/pdfparser.cpp b/Pdf4QtLib/sources/pdfparser.cpp
index f30abdd..7442cfa 100644
--- a/Pdf4QtLib/sources/pdfparser.cpp
+++ b/Pdf4QtLib/sources/pdfparser.cpp
@@ -32,7 +32,8 @@ namespace pdf
 PDFLexicalAnalyzer::PDFLexicalAnalyzer(const char* begin, const char* end) :
     m_begin(begin),
     m_current(begin),
-    m_end(end)
+    m_end(end),
+    m_tokenizingPostScriptFunction(false)
 {
 
 }
@@ -454,6 +455,16 @@ PDFLexicalAnalyzer::Token PDFLexicalAnalyzer::fetch()
                     return Token(TokenType::Command, std::move(command));
                 }
             }
+            else if (m_tokenizingPostScriptFunction)
+            {
+                const char currentChar = lookChar();
+                if (currentChar == CHAR_LEFT_CURLY_BRACKET || currentChar == CHAR_RIGHT_CURLY_BRACKET)
+                {
+                    return Token(TokenType::Command, QByteArray(1, fetchChar()));
+                }
+
+                error(tr("Unexpected character '%1' in the stream.").arg(currentChar));
+            }
             else
             {
                 error(tr("Unexpected character '%1' in the stream.").arg(lookChar()));
diff --git a/Pdf4QtLib/sources/pdfparser.h b/Pdf4QtLib/sources/pdfparser.h
index f890b8c..d1c4d3e 100644
--- a/Pdf4QtLib/sources/pdfparser.h
+++ b/Pdf4QtLib/sources/pdfparser.h
@@ -153,6 +153,9 @@ public:
     /// \param position Position, from which the search is started
     PDFInteger findSubstring(const char* str, PDFInteger position) const;
 
+    /// Switch parser mode for tokenizing PostScript function
+    void setTokenizingPostScriptFunction() { m_tokenizingPostScriptFunction = true; }
+
     /// Returns true, if character is a whitespace character according to the PDF 1.7 specification
     /// \param character Character to be tested
     static constexpr bool isWhitespace(char character);
@@ -198,6 +201,7 @@ private:
     const char* m_begin;
     const char* m_current;
     const char* m_end;
+    bool m_tokenizingPostScriptFunction;
 };
 
 /// Parsing context. Used for example to detect cyclic reference errors.