implement replace and swap

6 files changed, 442 insertions, 1 deletions

diff --git a/qpdf/qpdf.testcov b/qpdf/qpdf.testcov
index 4e7e292a..37ad350a 100644
--- a/qpdf/qpdf.testcov
+++ b/qpdf/qpdf.testcov
@@ -192,3 +192,4 @@ QPDF stream without newline 0
 QPDF stream with CR only 0
 QPDF stream with CRNL 0
 QPDF stream with NL only 0
+QPDF replaceObject called with indirect object 0
diff --git a/qpdf/qtest/qpdf.test b/qpdf/qtest/qpdf.test
index 75a92aa4..de82ce3b 100644
--- a/qpdf/qtest/qpdf.test
+++ b/qpdf/qtest/qpdf.test
@@ -111,7 +111,7 @@ $td->runtest("new stream",
 show_ntests();
 # ----------
 $td->notify("--- Miscellaneous Tests ---");
-$n_tests += 31;
+$n_tests += 33;
 
 $td->runtest("qpdf version",
 	     {$td->COMMAND => "qpdf --version"},
@@ -276,6 +276,15 @@ $td->runtest("check output",
 	     {$td->FILE => "a.qdf"},
 	     {$td->FILE => "stream-line-enders.qdf"});
 
+$td->runtest("swap and replace",
+	     {$td->COMMAND => "test_driver 14 test14-in.pdf"},
+	     {$td->FILE => "test14.out",
+	      $td->EXIT_STATUS => 0},
+	     $td->NORMALIZE_NEWLINES);
+$td->runtest("check output",
+	     {$td->FILE => "a.pdf"},
+	     {$td->FILE => "test14-out.pdf"});
+
 show_ntests();
 # ----------
 $td->notify("--- Error Condition Tests ---");
diff --git a/qpdf/qtest/qpdf/test14-in.pdf b/qpdf/qtest/qpdf/test14-in.pdf
new file mode 100644
index 00000000..4d761020
--- /dev/null
+++ b/qpdf/qtest/qpdf/test14-in.pdf
@@ -0,0 +1,264 @@
+%PDF-1.3
+%¿÷¢þ
+%QDF-1.0
+
+1 0 obj
+<<
+  /Pages 4 0 R
+  /Type /Catalog
+>>
+endobj
+
+2 0 obj
+[
+  /Array
+]
+endobj
+
+3 0 obj
+<<
+  /Dict 1
+>>
+endobj
+
+4 0 obj
+<<
+  /Count 4
+  /Kids [
+    5 0 R
+    6 0 R
+    7 0 R
+    8 0 R
+  ]
+  /Type /Pages
+>>
+endobj
+
+%% Page 1
+5 0 obj
+<<
+  /Contents 9 0 R
+  /MediaBox [
+    0
+    0
+    612
+    792
+  ]
+  /Parent 4 0 R
+  /Resources <<
+    /Font <<
+      /F1 11 0 R
+    >>
+    /ProcSet 12 0 R
+  >>
+  /Type /Page
+>>
+endobj
+
+%% Page 2
+6 0 obj
+<<
+  /Contents 13 0 R
+  /MediaBox [
+    0
+    0
+    612
+    792
+  ]
+  /Parent 4 0 R
+  /Resources <<
+    /Font <<
+      /F1 11 0 R
+    >>
+    /ProcSet 15 0 R
+  >>
+  /Type /Page
+>>
+endobj
+
+%% Page 3
+7 0 obj
+<<
+  /Contents 16 0 R
+  /MediaBox [
+    0
+    0
+    612
+    792
+  ]
+  /Parent 4 0 R
+  /Resources <<
+    /Font <<
+      /F1 11 0 R
+    >>
+    /ProcSet 18 0 R
+  >>
+  /Type /Page
+>>
+endobj
+
+%% Page 4
+8 0 obj
+<<
+  /Contents 19 0 R
+  /MediaBox [
+    0
+    0
+    612
+    792
+  ]
+  /Parent 4 0 R
+  /Resources <<
+    /Font <<
+      /F1 11 0 R
+    >>
+    /ProcSet 21 0 R
+  >>
+  /Type /Page
+>>
+endobj
+
+%% Contents for page 1
+9 0 obj
+<<
+  /Length 10 0 R
+>>
+stream
+BT
+  /F1 24 Tf
+  72 720 Td
+  (Potato 1) Tj
+ET
+endstream
+endobj
+
+10 0 obj
+46
+endobj
+
+11 0 obj
+<<
+  /BaseFont /Helvetica
+  /Encoding /WinAnsiEncoding
+  /Name /F1
+  /Subtype /Type1
+  /Type /Font
+>>
+endobj
+
+12 0 obj
+[
+  /PDF
+  /Text
+]
+endobj
+
+%% Contents for page 2
+13 0 obj
+<<
+  /Length 14 0 R
+>>
+stream
+BT
+  /F1 24 Tf
+  72 720 Td
+  (Potato 2) Tj
+ET
+endstream
+endobj
+
+14 0 obj
+46
+endobj
+
+15 0 obj
+[
+  /PDF
+  /Text
+]
+endobj
+
+%% Contents for page 3
+16 0 obj
+<<
+  /Length 17 0 R
+>>
+stream
+BT
+  /F1 24 Tf
+  72 720 Td
+  (Potato 3) Tj
+ET
+endstream
+endobj
+
+17 0 obj
+46
+endobj
+
+18 0 obj
+[
+  /PDF
+  /Text
+]
+endobj
+
+%% Contents for page 4
+19 0 obj
+<<
+  /Length 20 0 R
+>>
+stream
+BT
+  /F1 24 Tf
+  72 720 Td
+  (Potato 4) Tj
+ET
+endstream
+endobj
+
+20 0 obj
+46
+endobj
+
+21 0 obj
+[
+  /PDF
+  /Text
+]
+endobj
+
+xref
+0 22
+0000000000 65535 f 
+0000000025 00000 n 
+0000000079 00000 n 
+0000000108 00000 n 
+0000000140 00000 n 
+0000000252 00000 n 
+0000000456 00000 n 
+0000000661 00000 n 
+0000000866 00000 n 
+0000001084 00000 n 
+0000001186 00000 n 
+0000001206 00000 n 
+0000001325 00000 n 
+0000001384 00000 n 
+0000001487 00000 n 
+0000001507 00000 n 
+0000001566 00000 n 
+0000001669 00000 n 
+0000001689 00000 n 
+0000001748 00000 n 
+0000001851 00000 n 
+0000001871 00000 n 
+trailer <<
+  /QArray 2 0 R
+  /QDict 3 0 R
+  /Root 1 0 R
+  /Size 22
+  /ID [<20eb74876a3e8212c1b4fd43153860b0><1bb7a926da191c58f675435d77997d21>]
+>>
+startxref
+1907
+%%EOF
diff --git a/qpdf/qtest/qpdf/test14-out.pdf b/qpdf/qtest/qpdf/test14-out.pdf
new file mode 100644
index 00000000..315d174d
--- /dev/null
+++ b/qpdf/qtest/qpdf/test14-out.pdf
@@ -0,0 +1,105 @@
+%PDF-1.3
+%¿÷¢þ
+1 0 obj
+<< /Pages 4 0 R /Type /Catalog >>
+endobj
+2 0 obj
+<< /NewDict 2 >>
+endobj
+3 0 obj
+[ /Array ]
+endobj
+4 0 obj
+<< /Count 4 /Kids [ 5 0 R 6 0 R 7 0 R 8 0 R ] /Type /Pages >>
+endobj
+5 0 obj
+<< /Contents 9 0 R /MediaBox [ 0 0 612 792 ] /Parent 4 0 R /Resources << /Font << /F1 10 0 R >> /ProcSet 11 0 R >> /Type /Page >>
+endobj
+6 0 obj
+<< /Contents 12 0 R /MediaBox [ 0 0 612 792 ] /Parent 4 0 R /Resources << /Font << /F1 10 0 R >> /ProcSet 13 0 R >> /Type /Page >>
+endobj
+7 0 obj
+<< /Contents 14 0 R /MediaBox [ 0 0 612 792 ] /Parent 4 0 R /Resources << /Font << /F1 10 0 R >> /ProcSet 15 0 R >> /Type /Page >>
+endobj
+8 0 obj
+<< /Contents 16 0 R /MediaBox [ 0 0 612 792 ] /Parent 4 0 R /Resources << /Font << /F1 10 0 R >> /ProcSet 17 0 R >> /Type /Page >>
+endobj
+9 0 obj
+<< /Length 46 >>
+stream
+BT
+  /F1 24 Tf
+  72 720 Td
+  (Potato 1) Tj
+ET
+endstream
+endobj
+10 0 obj
+<< /BaseFont /Helvetica /Encoding /WinAnsiEncoding /Name /F1 /Subtype /Type1 /Type /Font >>
+endobj
+11 0 obj
+[ /PDF /Text ]
+endobj
+12 0 obj
+<< /Length 46 >>
+stream
+BT
+  /F1 24 Tf
+  72 720 Td
+  (Potato 3) Tj
+ET
+endstream
+endobj
+13 0 obj
+[ /PDF /Text ]
+endobj
+14 0 obj
+<< /Length 46 >>
+stream
+BT
+  /F1 24 Tf
+  72 720 Td
+  (Potato 2) Tj
+ET
+endstream
+endobj
+15 0 obj
+[ /PDF /Text ]
+endobj
+16 0 obj
+<< /Length 46 >>
+stream
+BT
+  /F1 24 Tf
+  72 720 Td
+  (Potato 4) Tj
+ET
+endstream
+endobj
+17 0 obj
+[ /PDF /Text ]
+endobj
+xref
+0 18
+0000000000 65535 f 
+0000000015 00000 n 
+0000000064 00000 n 
+0000000096 00000 n 
+0000000122 00000 n 
+0000000199 00000 n 
+0000000344 00000 n 
+0000000490 00000 n 
+0000000636 00000 n 
+0000000782 00000 n 
+0000000877 00000 n 
+0000000985 00000 n 
+0000001016 00000 n 
+0000001112 00000 n 
+0000001143 00000 n 
+0000001239 00000 n 
+0000001270 00000 n 
+0000001366 00000 n 
+trailer << /QArray 2 0 R /QDict 3 0 R /Root 1 0 R /Size 18 /ID [<20eb74876a3e8212c1b4fd43153860b0><31415926535897932384626433832795>] >>
+startxref
+1397
+%%EOF
diff --git a/qpdf/qtest/qpdf/test14.out b/qpdf/qtest/qpdf/test14.out
new file mode 100644
index 00000000..5b68d9f6
--- /dev/null
+++ b/qpdf/qtest/qpdf/test14.out
@@ -0,0 +1,6 @@
+caught logic error as expected
+old dict: 1
+old dict: 1
+new dict: 2
+swapped array: /Array
+test 14 done
diff --git a/qpdf/test_driver.cc b/qpdf/test_driver.cc
index c7b6a6b4..17451dc7 100644
--- a/qpdf/test_driver.cc
+++ b/qpdf/test_driver.cc
@@ -519,6 +519,62 @@ void runtest(int n, char const* filename)
 		  << "---error---" << std::endl
 		  << err.str();
     }
+    else if (n == 14)
+    {
+	// Exercise swap and replace.  This test case is designed for
+	// a specific file.
+	std::vector<QPDFObjectHandle> pages = pdf.getAllPages();
+	if (pages.size() != 4)
+	{
+	    throw std::logic_error("test " + QUtil::int_to_string(n) +
+				   " not called 4-page file");
+	}
+	// Swap pages 2 and 3
+	pdf.swapObjects(pages[1].getObjectID(), pages[1].getGeneration(),
+			pages[2].getObjectID(), pages[2].getGeneration());
+	// Replace object and swap objects
+	QPDFObjectHandle trailer = pdf.getTrailer();
+	QPDFObjectHandle qdict = trailer.getKey("/QDict");
+	QPDFObjectHandle qarray = trailer.getKey("/QArray");
+	// Force qdict but not qarray to resolve
+	qdict.isDictionary();
+	std::map<std::string, QPDFObjectHandle> dict_keys;
+	dict_keys["/NewDict"] = QPDFObjectHandle::newInteger(2);
+	QPDFObjectHandle new_dict = QPDFObjectHandle::newDictionary(dict_keys);
+	try
+	{
+	    // Do it wrong first...
+	    pdf.replaceObject(qdict.getObjectID(), qdict.getGeneration(),
+			      qdict);
+	}
+	catch (std::logic_error)
+	{
+	    std::cout << "caught logic error as expected" << std::endl;
+	}
+	pdf.replaceObject(qdict.getObjectID(), qdict.getGeneration(),
+			  new_dict);
+	// Now qdict still points to the old dictionary
+	std::cout << "old dict: " << qdict.getKey("/Dict").getIntValue()
+		  << std::endl;
+	// Swap dict and array
+	pdf.swapObjects(qdict.getObjectID(), qdict.getGeneration(),
+			qarray.getObjectID(), qarray.getGeneration());
+	// Now qarray will resolve to new object but qdict is still
+	// the old object
+	std::cout << "old dict: " << qdict.getKey("/Dict").getIntValue()
+		  << std::endl;
+	std::cout << "new dict: " << qarray.getKey("/NewDict").getIntValue()
+		  << std::endl;
+	// Reread qdict, now pointing to an array
+	qdict = pdf.getObjectByID(qdict.getObjectID(), qdict.getGeneration());
+	std::cout << "swapped array: " << qdict.getArrayItem(0).getName()
+		  << std::endl;
+
+	QPDFWriter w(pdf, "a.pdf");
+	w.setStaticID(true);
+	w.setStreamDataMode(qpdf_s_preserve);
+	w.write();
+    }
     else
     {
 	throw std::runtime_error(std::string("invalid test ") +