QPDFObjGen : tidy QPDF private methods

Change method signatures to use QPDFObjGen. Use QPDFObjGen methods where possible. Remove redundant QPDF::objGenToIndirect.

QPDFObjGen : tidy QPDF private methods
Change method signatures to use QPDFObjGen. Use QPDFObjGen methods where possible. Remove redundant QPDF::objGenToIndirect.
m-holger
1 parent 3404ca8a
Showing 9 changed files with 103 additions and 165 deletions
include/qpdf/QPDF.hh
libqpdf/QPDF.cc
libqpdf/QPDFObjectHandle.cc
libqpdf/QPDF_Stream.cc
libqpdf/QPDF_encryption.cc
libqpdf/QPDF_json.cc
libqpdf/QPDF_linearization.cc
libqpdf/QPDF_optimization.cc
libqpdf/QPDF_pages.cc
@@ -815,9 +815,9 @@ class QPDF
       private:
         static std::shared_ptr<QPDFObject>
-        resolve(QPDF* qpdf, int objid, int generation)
+        resolve(QPDF* qpdf, QPDFObjGen const& og)
         {
-            return qpdf->resolve(objid, generation);
+            return qpdf->resolve(og);
         }
         static bool
         objectChanged(
@@ -879,8 +879,7 @@ class QPDF
         static bool
         pipeStreamData(
             QPDF* qpdf,
-            int objid,
-            int generation,
+            QPDFObjGen const& og,
             qpdf_offset_t offset,
             size_t length,
             QPDFObjectHandle dict,
@@ -889,8 +888,7 @@ class QPDF
             bool will_retry)
         {
             return qpdf->pipeStreamData(
-                objid,
-                generation,
+                og,
                 offset,
                 length,
                 dict,
@@ -959,8 +957,7 @@ class QPDF
         std::string user_password;
         std::string encryption_key;
         std::string cached_object_encryption_key;
-        int cached_key_objid;
-        int cached_key_generation;
+        QPDFObjGen cached_key_og;
         bool user_password_matched;
         bool owner_password_matched;
     };
@@ -973,8 +970,7 @@ class QPDF
         ForeignStreamData(
             std::shared_ptr<EncryptionParameters> encp,
             std::shared_ptr<InputSource> file,
-            int foreign_objid,
-            int foreign_generation,
+            QPDFObjGen const& foreign_og,
             qpdf_offset_t offset,
             size_t length,
             QPDFObjectHandle local_dict);
@@ -982,8 +978,7 @@ class QPDF
       private:
         std::shared_ptr<EncryptionParameters> encp;
         std::shared_ptr<InputSource> file;
-        int foreign_objid;
-        int foreign_generation;
+        QPDFObjGen foreign_og;
         qpdf_offset_t offset;
         size_t length;
         QPDFObjectHandle local_dict;
@@ -1017,14 +1012,13 @@ class QPDF
         friend class QPDF;
       public:
-        StringDecrypter(QPDF* qpdf, int objid, int gen);
+        StringDecrypter(QPDF* qpdf, QPDFObjGen const& og);
         virtual ~StringDecrypter() = default;
         virtual void decryptString(std::string& val);
       private:
         QPDF* qpdf;
-        int objid;
-        int gen;
+        QPDFObjGen og;
     };
     class ResolveRecorder
@@ -1127,17 +1121,15 @@ class QPDF
     void insertXrefEntry(
         int obj, int f0, qpdf_offset_t f1, int f2, bool overwrite = false);
     void setLastObjectDescription(
-        std::string const& description, int objid, int generation);
+        std::string const& description, QPDFObjGen const& og);
     QPDFObjectHandle readObject(
         std::shared_ptr<InputSource>,
         std::string const& description,
-        int objid,
-        int generation,
+        QPDFObjGen const& og,
         bool in_object_stream);
     size_t recoverStreamLength(
         std::shared_ptr<InputSource> input,
-        int objid,
-        int generation,
+        QPDFObjGen const& og,
         qpdf_offset_t stream_offset);
     QPDFTokenizer::Token
     readToken(std::shared_ptr<InputSource>, size_t max_len = 0);
@@ -1149,16 +1141,15 @@ class QPDF
         QPDFObjGen const& exp_og,
         QPDFObjGen& og);
     bool objectChanged(QPDFObjGen const& og, std::shared_ptr<QPDFObject>& oph);
-    std::shared_ptr<QPDFObject> resolve(int objid, int generation);
+    std::shared_ptr<QPDFObject> resolve(QPDFObjGen const& og);
     void resolveObjectsInStream(int obj_stream_number);
     void stopOnError(std::string const& message);
-    QPDFObjectHandle reserveObjectIfNotExists(int objid, int gen);
-    QPDFObjectHandle reserveStream(int objid, int gen);
+    QPDFObjectHandle reserveObjectIfNotExists(QPDFObjGen const& og);
+    QPDFObjectHandle reserveStream(QPDFObjGen const& og);
     // Calls finish() on the pipeline when done but does not delete it
     bool pipeStreamData(
-        int objid,
-        int generation,
+        QPDFObjGen const& og,
         qpdf_offset_t offset,
         size_t length,
         QPDFObjectHandle dict,
@@ -1174,8 +1165,7 @@ class QPDF
         std::shared_ptr<QPDF::EncryptionParameters> encp,
         std::shared_ptr<InputSource> file,
         QPDF& qpdf_for_warning,
-        int objid,
-        int generation,
+        QPDFObjGen const& og,
         qpdf_offset_t offset,
         size_t length,
         QPDFObjectHandle dict,
@@ -1228,10 +1218,9 @@ class QPDF
     void initializeEncryption();
     static std::string getKeyForObject(
         std::shared_ptr<EncryptionParameters> encp,
-        int objid,
-        int generation,
+        QPDFObjGen const& og,
         bool use_aes);
-    void decryptString(std::string&, int objid, int generation);
+    void decryptString(std::string&, QPDFObjGen const& og);
     static std::string compute_encryption_key_from_password(
         std::string const& password, EncryptionData const& data);
     static std::string recover_encryption_key_with_password(
@@ -1245,8 +1234,7 @@ class QPDF
         std::shared_ptr<InputSource> file,
         QPDF& qpdf_for_warning,
         Pipeline*& pipeline,
-        int objid,
-        int generation,
+        QPDFObjGen const& og,
         QPDFObjectHandle& stream_dict,
         std::vector<std::shared_ptr<Pipeline>>& heap);
@@ -1569,7 +1557,6 @@ class QPDF
     void dumpHSharedObject();
     void dumpHGeneric(HGeneric&);
     qpdf_offset_t adjusted_offset(qpdf_offset_t offset);
-    QPDFObjectHandle objGenToIndirect(QPDFObjGen const&);
     void
     calculateLinearizationData(std::map<int, int> const& object_stream_data);
     void pushOutlinesToPart(
@@ -113,15 +113,13 @@ namespace
 QPDF::ForeignStreamData::ForeignStreamData(
     std::shared_ptr<EncryptionParameters> encp,
     std::shared_ptr<InputSource> file,
-    int foreign_objid,
-    int foreign_generation,
+    QPDFObjGen const& foreign_og,
     qpdf_offset_t offset,
     size_t length,
     QPDFObjectHandle local_dict) :
     encp(encp),
     file(file),
-    foreign_objid(foreign_objid),
-    foreign_generation(foreign_generation),
+    foreign_og(foreign_og),
     offset(offset),
     length(length),
     local_dict(local_dict)
@@ -176,17 +174,16 @@ QPDF::CopiedStreamDataProvider::registerForeignStream(
     this->foreign_stream_data[local_og] = foreign_stream;
 }
-QPDF::StringDecrypter::StringDecrypter(QPDF* qpdf, int objid, int gen) :
+QPDF::StringDecrypter::StringDecrypter(QPDF* qpdf, QPDFObjGen const& og) :
     qpdf(qpdf),
-    objid(objid),
-    gen(gen)
+    og(og)
 {
 }
 void
 QPDF::StringDecrypter::decryptString(std::string& val)
 {
-    qpdf->decryptString(val, objid, gen);
+    qpdf->decryptString(val, og);
 }
 std::string const&
@@ -205,8 +202,6 @@ QPDF::EncryptionParameters::EncryptionParameters() :
     cf_stream(e_none),
     cf_string(e_none),
     cf_file(e_none),
-    cached_key_objid(0),
-    cached_key_generation(0),
     user_password_matched(false),
     owner_password_matched(false)
 {
@@ -631,7 +626,7 @@ QPDF::reconstruct_xref(QPDFExc&amp; e)
             (!this->m->trailer.isInitialized()) &&
             (t1 == QPDFTokenizer::Token(QPDFTokenizer::tt_word, "trailer"))) {
             QPDFObjectHandle t =
-                readObject(this->m->file, "trailer", 0, 0, false);
+                readObject(this->m->file, "trailer", QPDFObjGen(), false);
             if (!t.isDictionary()) {
                 // Oh well.  It was worth a try.
             } else {
@@ -969,7 +964,7 @@ QPDF::read_xrefTable(qpdf_offset_t xref_offset)
     // Set offset to previous xref table if any
     QPDFObjectHandle cur_trailer =
-        readObject(this->m->file, "trailer", 0, 0, false);
+        readObject(this->m->file, "trailer", QPDFObjGen(), false);
     if (!cur_trailer.isDictionary()) {
         QTC::TC("qpdf", "QPDF missing trailer");
         throw QPDFExc(
@@ -1341,7 +1336,7 @@ QPDF::insertXrefEntry(int obj, int f0, qpdf_offset_t f1, int f2, bool overwrite)
         break;
     case 2:
-        this->m->xref_table[QPDFObjGen(obj, 0)] = QPDFXRefEntry(f0, f1, f2);
+        this->m->xref_table[QPDFObjGen(obj)] = QPDFXRefEntry(f0, f1, f2);
         break;
     default:
@@ -1362,7 +1357,7 @@ QPDF::showXRefTable()
     for (auto const& iter: this->m->xref_table) {
         QPDFObjGen const& og = iter.first;
         QPDFXRefEntry const& entry = iter.second;
-        cout << og.getObj() << "/" << og.getGen() << ": ";
+        cout << og.unparse('/') << ": ";
         switch (entry.getType()) {
         case 1:
             cout << "uncompressed; offset = " << entry.getOffset();
@@ -1478,18 +1473,17 @@ QPDF::getAllObjects()
 void
 QPDF::setLastObjectDescription(
-    std::string const& description, int objid, int generation)
+    std::string const& description, QPDFObjGen const& og)
 {
     this->m->last_object_description.clear();
     if (!description.empty()) {
         this->m->last_object_description += description;
-        if (objid > 0) {
+        if (og.isIndirect()) {
             this->m->last_object_description += ": ";
         }
     }
-    if (objid > 0) {
-        this->m->last_object_description +=
-            "object " + QPDFObjGen(objid, generation).unparse(' ');
+    if (og.isIndirect()) {
+        this->m->last_object_description += "object " + og.unparse(' ');
     }
 }
@@ -1497,19 +1491,17 @@ QPDFObjectHandle
 QPDF::readObject(
     std::shared_ptr<InputSource> input,
     std::string const& description,
-    int objid,
-    int generation,
+    QPDFObjGen const& og,
     bool in_object_stream)
 {
-    setLastObjectDescription(description, objid, generation);
+    setLastObjectDescription(description, og);
     qpdf_offset_t offset = input->tell();
     bool empty = false;
     std::shared_ptr<StringDecrypter> decrypter_ph;
     StringDecrypter* decrypter = 0;
     if (this->m->encp->encrypted && (!in_object_stream)) {
-        decrypter_ph =
-            std::make_shared<StringDecrypter>(this, objid, generation);
+        decrypter_ph = std::make_shared<StringDecrypter>(this, og);
         decrypter = decrypter_ph.get();
     }
     QPDFObjectHandle object = QPDFObjectHandle::parse(
@@ -1651,18 +1643,13 @@ QPDF::readObject(
             } catch (QPDFExc& e) {
                 if (this->m->attempt_recovery) {
                     warn(e);
-                    length = recoverStreamLength(
-                        input, objid, generation, stream_offset);
+                    length = recoverStreamLength(input, og, stream_offset);
                 } else {
                     throw e;
                 }
             }
             object = QPDFObjectHandle::Factory::newStream(
-                this,
-                QPDFObjGen(objid, generation),
-                object,
-                stream_offset,
-                length);
+                this, og, object, stream_offset, length);
         } else {
             input->seek(cur_offset, SEEK_SET);
         }
@@ -1690,8 +1677,7 @@ QPDF::findEndstream()
 size_t
 QPDF::recoverStreamLength(
     std::shared_ptr<InputSource> input,
-    int objid,
-    int generation,
+    QPDFObjGen const& og,
     qpdf_offset_t stream_offset)
 {
     // Try to reconstruct stream length by looking for
@@ -1716,11 +1702,10 @@ QPDF::recoverStreamLength(
     if (length) {
         qpdf_offset_t this_obj_offset = 0;
-        QPDFObjGen this_obj(0, 0);
+        QPDFObjGen this_og;
         // Make sure this is inside this object
         for (auto const& iter: this->m->xref_table) {
-            QPDFObjGen const& og = iter.first;
             QPDFXRefEntry const& entry = iter.second;
             if (entry.getType() == 1) {
                 qpdf_offset_t obj_offset = entry.getOffset();
@@ -1728,12 +1713,11 @@ QPDF::recoverStreamLength(
                     ((this_obj_offset == 0) ||
                      (this_obj_offset > obj_offset))) {
                     this_obj_offset = obj_offset;
-                    this_obj = og;
+                    this_og = iter.first;
                 }
             }
         }
-        if (this_obj_offset && (this_obj.getObj() == objid) &&
-            (this_obj.getGen() == generation)) {
+        if (this_obj_offset && (this_og == og)) {
             // Well, we found endstream\nendobj within the space
             // allowed for this object, so we're probably in good
             // shape.
@@ -1791,7 +1775,7 @@ QPDF::readObjectAtOffset(
         check_og = false;
         try_recovery = false;
     } else {
-        setLastObjectDescription(description, exp_og.getObj(), exp_og.getGen());
+        setLastObjectDescription(description, exp_og);
     }
     if (!this->m->attempt_recovery) {
@@ -1895,8 +1879,7 @@ QPDF::readObjectAtOffset(
         }
     }
-    QPDFObjectHandle oh =
-        readObject(this->m->file, description, og.getObj(), og.getGen(), false);
+    QPDFObjectHandle oh = readObject(this->m->file, description, og, false);
     if (!(readToken(this->m->file) ==
           QPDFTokenizer::Token(QPDFTokenizer::tt_word, "endobj"))) {
@@ -1972,12 +1955,11 @@ QPDF::objectChanged(QPDFObjGen const&amp; og, std::shared_ptr&lt;QPDFObject&gt;&amp; oph)
 }
 std::shared_ptr<QPDFObject>
-QPDF::resolve(int objid, int generation)
+QPDF::resolve(QPDFObjGen const& og)
 {
     // Check object cache before checking xref table.  This allows us
     // to insert things into the object cache that don't actually
     // exist in the file.
-    QPDFObjGen og(objid, generation);
     if (this->m->resolving.count(og)) {
         // This can happen if an object references itself directly or
         // indirectly in some key that has to be resolved during
@@ -2131,13 +2113,13 @@ QPDF::resolveObjectsInStream(int obj_stream_number)
     // xref table and only cache what would actually be resolved here.
     for (auto const& iter: offsets) {
         int obj = iter.first;
-        QPDFObjGen og(obj, 0);
+        QPDFObjGen og(obj);
         QPDFXRefEntry const& entry = this->m->xref_table[og];
         if ((entry.getType() == 2) &&
             (entry.getObjStreamNumber() == obj_stream_number)) {
             int offset = iter.second;
             input->seek(offset, SEEK_SET);
-            QPDFObjectHandle oh = readObject(input, "", obj, 0, true);
+            QPDFObjectHandle oh = readObject(input, "", og, true);
             this->m->obj_cache[og] = ObjCache(
                 QPDFObjectHandle::ObjAccessor::getObject(oh),
                 end_before_space,
@@ -2163,21 +2145,20 @@ QPDF::makeIndirectObject(QPDFObjectHandle oh)
 }
 QPDFObjectHandle
-QPDF::reserveObjectIfNotExists(int objid, int gen)
+QPDF::reserveObjectIfNotExists(QPDFObjGen const& og)
 {
-    QPDFObjGen og(objid, gen);
     if ((!this->m->obj_cache.count(og)) && (!this->m->xref_table.count(og))) {
-        resolve(objid, gen);
-        replaceObject(objid, gen, QPDFObjectHandle::Factory::makeReserved());
+        resolve(og);
+        replaceObject(og, QPDFObjectHandle::Factory::makeReserved());
     }
-    return getObjectByID(objid, gen);
+    return getObjectByObjGen(og);
 }
 QPDFObjectHandle
-QPDF::reserveStream(int objid, int gen)
+QPDF::reserveStream(QPDFObjGen const& og)
 {
     return QPDFObjectHandle::Factory::newStream(
-        this, QPDFObjGen(objid, gen), QPDFObjectHandle::newDictionary(), 0, 0);
+        this, og, QPDFObjectHandle::newDictionary(), 0, 0);
 }
 QPDFObjectHandle
@@ -2193,13 +2174,13 @@ QPDF::getObjectByID(int objid, int generation)
 }
 void
-QPDF::replaceObject(QPDFObjGen const& og, QPDFObjectHandle oh)
+QPDF::replaceObject(int objid, int generation, QPDFObjectHandle oh)
 {
-    replaceObject(og.getObj(), og.getGen(), oh);
+    replaceObject(QPDFObjGen(objid, generation), oh);
 }
 void
-QPDF::replaceObject(int objid, int generation, QPDFObjectHandle oh)
+QPDF::replaceObject(QPDFObjGen const& og, QPDFObjectHandle oh)
 {
     if (oh.isIndirect()) {
         QTC::TC("qpdf", "QPDF replaceObject called with indirect object");
@@ -2208,10 +2189,9 @@ QPDF::replaceObject(int objid, int generation, QPDFObjectHandle oh)
     }
     // Force new object to appear in the cache
-    resolve(objid, generation);
+    resolve(og);
     // Replace the object in the object cache
-    QPDFObjGen og(objid, generation);
     this->m->ever_replaced_objects = true;
     this->m->obj_cache[og] =
         ObjCache(QPDFObjectHandle::ObjAccessor::getObject(oh), -1, -1);
@@ -2511,8 +2491,7 @@ QPDF::copyStreamData(QPDFObjectHandle result, QPDFObjectHandle foreign)
         auto foreign_stream_data = std::make_shared<ForeignStreamData>(
             foreign_stream_qpdf->m->encp,
             foreign_stream_qpdf->m->file,
-            foreign.getObjectID(),
-            foreign.getGeneration(),
+            foreign.getObjGen(),
             stream->getOffset(),
             stream->getLength(),
             dict);
@@ -2526,20 +2505,19 @@ QPDF::copyStreamData(QPDFObjectHandle result, QPDFObjectHandle foreign)
 }
 void
-QPDF::swapObjects(QPDFObjGen const& og1, QPDFObjGen const& og2)
+QPDF::swapObjects(int objid1, int generation1, int objid2, int generation2)
 {
-    swapObjects(og1.getObj(), og1.getGen(), og2.getObj(), og2.getGen());
+    swapObjects(
+        QPDFObjGen(objid1, generation1), QPDFObjGen(objid2, generation2));
 }
 void
-QPDF::swapObjects(int objid1, int generation1, int objid2, int generation2)
+QPDF::swapObjects(QPDFObjGen const& og1, QPDFObjGen const& og2)
 {
     // Force objects to be loaded into cache; then swap them in the
     // cache.
-    resolve(objid1, generation1);
-    resolve(objid2, generation2);
-    QPDFObjGen og1(objid1, generation1);
-    QPDFObjGen og2(objid2, generation2);
+    resolve(og1);
+    resolve(og2);
     ObjCache t = this->m->obj_cache[og1];
     this->m->ever_replaced_objects = true;
     this->m->obj_cache[og1] = this->m->obj_cache[og2];
@@ -2723,8 +2701,7 @@ QPDF::pipeStreamData(
     std::shared_ptr<EncryptionParameters> encp,
     std::shared_ptr<InputSource> file,
     QPDF& qpdf_for_warning,
-    int objid,
-    int generation,
+    QPDFObjGen const& og,
     qpdf_offset_t offset,
     size_t length,
     QPDFObjectHandle stream_dict,
@@ -2735,14 +2712,7 @@ QPDF::pipeStreamData(
     std::vector<std::shared_ptr<Pipeline>> to_delete;
     if (encp->encrypted) {
         decryptStream(
-            encp,
-            file,
-            qpdf_for_warning,
-            pipeline,
-            objid,
-            generation,
-            stream_dict,
-            to_delete);
+            encp, file, qpdf_for_warning, pipeline, og, stream_dict, to_delete);
     }
     bool success = false;
@@ -2780,8 +2750,7 @@ QPDF::pipeStreamData(
                     "",
                     file->getLastOffset(),
                     ("error decoding stream data for object " +
-                     QPDFObjGen(objid, generation).unparse(' ') + ": " +
-                     e.what())));
+                     og.unparse(' ') + ": " + e.what())));
             if (will_retry) {
                 qpdf_for_warning.warn(
                     // line-break
@@ -2807,8 +2776,7 @@ QPDF::pipeStreamData(
 bool
 QPDF::pipeStreamData(
-    int objid,
-    int generation,
+    QPDFObjGen const& og,
     qpdf_offset_t offset,
     size_t length,
     QPDFObjectHandle stream_dict,
@@ -2820,8 +2788,7 @@ QPDF::pipeStreamData(
         this->m->encp,
         this->m->file,
         *this,
-        objid,
-        generation,
+        og,
         offset,
         length,
         stream_dict,
@@ -2844,8 +2811,7 @@ QPDF::pipeForeignStreamData(
         foreign->encp,
         foreign->file,
         *this,
-        foreign->foreign_objid,
-        foreign->foreign_generation,
+        foreign->foreign_og,
         foreign->offset,
         foreign->length,
         foreign->local_dict,
@@ -3098,7 +3098,7 @@ QPDFObjectHandle::dereference()
     }
     if (this->obj.get() == 0) {
         std::shared_ptr<QPDFObject> obj =
-            QPDF::Resolver::resolve(this->qpdf, getObjectID(), getGeneration());
+            QPDF::Resolver::resolve(this->qpdf, getObjGen());
         if (obj.get() == 0) {
             // QPDF::resolve never returns an uninitialized object, but
             // check just in case.
@@ -658,8 +658,7 @@ QPDF_Stream::pipeStreamData(
         QTC::TC("qpdf", "QPDF_Stream pipe original stream data");
         if (!QPDF::Pipe::pipeStreamData(
                 this->qpdf,
-                this->objid,
-                this->generation,
+                QPDFObjGen(this->objid, this->generation),
                 this->offset,
                 this->length,
                 this->stream_dict,
@@ -1075,8 +1075,7 @@ QPDF::initializeEncryption()
 std::string
 QPDF::getKeyForObject(
     std::shared_ptr<EncryptionParameters> encp,
-    int objid,
-    int generation,
+    QPDFObjGen const& og,
     bool use_aes)
 {
     if (!encp->encrypted) {
@@ -1084,26 +1083,24 @@ QPDF::getKeyForObject(
             "request for encryption key in non-encrypted PDF");
     }
-    if (!((objid == encp->cached_key_objid) &&
-          (generation == encp->cached_key_generation))) {
+    if (og != encp->cached_key_og) {
         encp->cached_object_encryption_key = compute_data_key(
             encp->encryption_key,
-            objid,
-            generation,
+            og.getObj(),
+            og.getGen(),
             use_aes,
             encp->encryption_V,
             encp->encryption_R);
-        encp->cached_key_objid = objid;
-        encp->cached_key_generation = generation;
+        encp->cached_key_og = og;
     }
     return encp->cached_object_encryption_key;
 }
 void
-QPDF::decryptString(std::string& str, int objid, int generation)
+QPDF::decryptString(std::string& str, QPDFObjGen const& og)
 {
-    if (objid == 0) {
+    if (!og.isIndirect()) {
         return;
     }
     bool use_aes = false;
@@ -1139,8 +1136,7 @@ QPDF::decryptString(std::string&amp; str, int objid, int generation)
         }
     }
-    std::string key =
-        getKeyForObject(this->m->encp, objid, generation, use_aes);
+    std::string key = getKeyForObject(this->m->encp, og, use_aes);
     try {
         if (use_aes) {
             QTC::TC("qpdf", "QPDF_encryption aes decode string");
@@ -1175,8 +1171,8 @@ QPDF::decryptString(std::string&amp; str, int objid, int generation)
             this->m->file->getName(),
             this->m->last_object_description,
             this->m->file->getLastOffset(),
-            "error decrypting string for object " +
-                QPDFObjGen(objid, generation).unparse() + ": " + e.what());
+            "error decrypting string for object " + og.unparse() + ": " +
+                e.what());
     }
 }
@@ -1186,8 +1182,7 @@ QPDF::decryptStream(
     std::shared_ptr<InputSource> file,
     QPDF& qpdf_for_warning,
     Pipeline*& pipeline,
-    int objid,
-    int generation,
+    QPDFObjGen const& og,
     QPDFObjectHandle& stream_dict,
     std::vector<std::shared_ptr<Pipeline>>& heap)
 {
@@ -1282,7 +1277,7 @@ QPDF::decryptStream(
             break;
         }
     }
-    std::string key = getKeyForObject(encp, objid, generation, use_aes);
+    std::string key = getKeyForObject(encp, og, use_aes);
     std::shared_ptr<Pipeline> new_pipeline;
     if (use_aes) {
         QTC::TC("qpdf", "QPDF_encryption aes decode stream");
@@ -371,9 +371,10 @@ QPDF::JSONReactor::containerEnd(JSON const&amp; value)
 QPDFObjectHandle
 QPDF::JSONReactor::reserveObject(int obj, int gen)
 {
-    auto oh = pdf.reserveObjectIfNotExists(obj, gen);
+    QPDFObjGen og(obj, gen);
+    auto oh = pdf.reserveObjectIfNotExists(og);
     if (oh.isReserved()) {
-        this->reserved.insert(QPDFObjGen(obj, gen));
+        this->reserved.insert(og);
     }
     return oh;
 }
@@ -495,8 +496,7 @@ QPDF::JSONReactor::dictionaryItem(std::string const&amp; key, JSON const&amp; value)
                 QTC::TC("qpdf", "QPDF_json updating existing stream");
             } else {
                 this->this_stream_needs_data = true;
-                replacement =
-                    pdf.reserveStream(tos.getObjectID(), tos.getGeneration());
+                replacement = pdf.reserveStream(tos.getObjGen());
                 replaceObject(tos, replacement, value);
             }
         } else {
@@ -706,7 +706,7 @@ QPDF::getUncompressedObject(
         return obj;
     } else {
         int repl = (*(object_stream_data.find(obj.getObjectID()))).second;
-        return objGenToIndirect(QPDFObjGen(repl, 0));
+        return getObjectByObjGen(QPDFObjGen(repl));
     }
 }
@@ -1143,12 +1143,6 @@ QPDF::dumpHGeneric(HGeneric&amp; t)
         << "group_length: " << t.group_length << "\n";
 }
-QPDFObjectHandle
-QPDF::objGenToIndirect(QPDFObjGen const& og)
-{
-    return getObjectByID(og.getObj(), og.getGen());
-}
-
 void
 QPDF::calculateLinearizationData(std::map<int, int> const& object_stream_data)
 {
@@ -1387,9 +1381,9 @@ QPDF::calculateLinearizationData(std::map&lt;int, int&gt; const&amp; object_stream_data)
         stopOnError("found other than one root while"
                     " calculating linearization data");
     }
-    this->m->part4.push_back(objGenToIndirect(*(lc_root.begin())));
+    this->m->part4.push_back(getObjectByObjGen(*(lc_root.begin())));
     for (auto const& og: lc_open_document) {
-        this->m->part4.push_back(objGenToIndirect(og));
+        this->m->part4.push_back(getObjectByObjGen(og));
     }
     // Part 6: first page objects.  Note: implementation note 124
@@ -1418,11 +1412,11 @@ QPDF::calculateLinearizationData(std::map&lt;int, int&gt; const&amp; object_stream_data)
     // hint tables.
     for (auto const& og: lc_first_page_private) {
-        this->m->part6.push_back(objGenToIndirect(og));
+        this->m->part6.push_back(getObjectByObjGen(og));
     }
     for (auto const& og: lc_first_page_shared) {
-        this->m->part6.push_back(objGenToIndirect(og));
+        this->m->part6.push_back(getObjectByObjGen(og));
     }
     // Place the outline dictionary if it goes in the first page section.
@@ -1468,7 +1462,7 @@ QPDF::calculateLinearizationData(std::map&lt;int, int&gt; const&amp; object_stream_data)
         for (auto const& og: this->m->obj_user_to_objects[ou]) {
             if (lc_other_page_private.count(og)) {
                 lc_other_page_private.erase(og);
-                this->m->part7.push_back(objGenToIndirect(og));
+                this->m->part7.push_back(getObjectByObjGen(og));
                 ++this->m->c_page_offset_data.entries.at(i).nobjects;
             }
         }
@@ -1485,7 +1479,7 @@ QPDF::calculateLinearizationData(std::map&lt;int, int&gt; const&amp; object_stream_data)
     // Order is unimportant.
     for (auto const& og: lc_other_page_shared) {
-        this->m->part8.push_back(objGenToIndirect(og));
+        this->m->part8.push_back(getObjectByObjGen(og));
     }
     // Part 9: other objects
@@ -1507,7 +1501,7 @@ QPDF::calculateLinearizationData(std::map&lt;int, int&gt; const&amp; object_stream_data)
     for (auto const& og: pages_ogs) {
         if (lc_other.count(og)) {
             lc_other.erase(og);
-            this->m->part9.push_back(objGenToIndirect(og));
+            this->m->part9.push_back(getObjectByObjGen(og));
         }
     }
@@ -1537,7 +1531,7 @@ QPDF::calculateLinearizationData(std::map&lt;int, int&gt; const&amp; object_stream_data)
             for (auto const& og: ogs) {
                 if (lc_thumbnail_private.count(og)) {
                     lc_thumbnail_private.erase(og);
-                    this->m->part9.push_back(objGenToIndirect(og));
+                    this->m->part9.push_back(getObjectByObjGen(og));
                 }
             }
         }
@@ -1550,7 +1544,7 @@ QPDF::calculateLinearizationData(std::map&lt;int, int&gt; const&amp; object_stream_data)
     // Place shared thumbnail objects
     for (auto const& og: lc_thumbnail_shared) {
-        this->m->part9.push_back(objGenToIndirect(og));
+        this->m->part9.push_back(getObjectByObjGen(og));
     }
     // Place outlines unless in first page
@@ -1560,7 +1554,7 @@ QPDF::calculateLinearizationData(std::map&lt;int, int&gt; const&amp; object_stream_data)
     // Place all remaining objects
     for (auto const& og: lc_other) {
-        this->m->part9.push_back(objGenToIndirect(og));
+        this->m->part9.push_back(getObjectByObjGen(og));
     }
     // Make sure we got everything exactly once.
@@ -1662,7 +1656,7 @@ QPDF::pushOutlinesToPart(
     lc_outlines.erase(outlines_og);
     part.push_back(outlines);
     for (auto const& og: lc_outlines) {
-        part.push_back(objGenToIndirect(og));
+        part.push_back(getObjectByObjGen(og));
         ++this->m->c_outline_data.nobjects;
     }
 }
@@ -252,9 +252,7 @@ QPDF::pushInheritedAttributesToPageInternal(
                 if ((warn_skipped_keys) && (cur_pages.hasKey("/Parent"))) {
                     QTC::TC("qpdf", "QPDF unknown key not inherited");
                     setLastObjectDescription(
-                        "Pages object",
-                        cur_pages.getObjectID(),
-                        cur_pages.getGeneration());
+                        "Pages object", cur_pages.getObjGen());
                     warn(
                         qpdf_e_pages,
                         this->m->last_object_description,
@@ -207,8 +207,7 @@ QPDF::insertPageobjToPage(
             // that causes this to happen.
             setLastObjectDescription(
                 "page " + QUtil::int_to_string(pos) + " (numbered from zero)",
-                og.getObj(),
-                og.getGen());
+                og);
             throw QPDFExc(
                 qpdf_e_pages,
                 this->m->file->getName(),
@@ -334,7 +333,7 @@ QPDF::findPage(QPDFObjGen const&amp; og)
     auto it = this->m->pageobj_to_pages_pos.find(og);
     if (it == this->m->pageobj_to_pages_pos.end()) {
         QTC::TC("qpdf", "QPDF_pages findPage not found");
-        setLastObjectDescription("page object", og.getObj(), og.getGen());
+        setLastObjectDescription("page object", og);
         throw QPDFExc(
             qpdf_e_pages,
             this->m->file->getName(),