Change list to vector for outline helpers (fixes #297)

This change works around STL problems with Embarcadero C++ Builder
version 10.2, but std::vector is more common than std::list in qpdf,
and this is a relatively new API, so an API change is tolerable.

Thanks to Thorsten Schöning <6223655+ams-tschoening@users.noreply.github.com>
for the fix.

ChangeLog

@@ -1,3 +1,13 @@
+2019-07-03  Jay Berkenbilt  <ejb@ql.org>
+
+	* Non-compatible API change: change
+	QPDFOutlineDocumentHelper::getTopLevelOutlines and
+	QPDFOutlineObjectHelper::getKids to return a std::vector instead
+	of a std::list of QPDFOutlineObjectHelper objects. This is to work
+	around bugs with some compilers' STL implementations that are
+	choking with list here. There's no deep reason for these to be
+	lists instead of vectors. Fixes #297.
+
 2019-06-22  Jay Berkenbilt  <ejb@ql.org>
 
 	* Handle encrypted files with missing or invalid /Length entries

examples/pdf-bookmarks.cc

@@ -135,16 +135,16 @@ void show_bookmark_details(QPDFOutlineObjectHelper outline,
     std::cout << outline.getTitle() << std::endl;
 }
 
-void extract_bookmarks(std::list<QPDFOutlineObjectHelper> outlines,
+void extract_bookmarks(std::vector<QPDFOutlineObjectHelper> outlines,
                        std::vector<int>& numbers)
 {
     numbers.push_back(0);
-    for (std::list<QPDFOutlineObjectHelper>::iterator iter = outlines.begin();
+    for (std::vector<QPDFOutlineObjectHelper>::iterator iter = outlines.begin();
          iter != outlines.end(); ++iter)
     {
         ++(numbers.back());
         show_bookmark_details(*iter, numbers);
-        std::list<QPDFOutlineObjectHelper>::iterator next = iter;
+        std::vector<QPDFOutlineObjectHelper>::iterator next = iter;
         ++next;
         bool has_next = (next != outlines.end());
         if ((style == st_lines) && (! has_next))

fuzz/qpdf_fuzzer.cc

@@ -170,13 +170,13 @@ void
 FuzzHelper::testOutlines()
 {
     PointerHolder<QPDF> q = getQpdf();
-    std::list<std::list<QPDFOutlineObjectHelper> > queue;
+    std::list<std::vector<QPDFOutlineObjectHelper> > queue;
     QPDFOutlineDocumentHelper odh(*q);
     queue.push_back(odh.getTopLevelOutlines());
     while (! queue.empty())
     {
-        std::list<QPDFOutlineObjectHelper>& outlines = *(queue.begin());
+        std::vector<QPDFOutlineObjectHelper>& outlines = *(queue.begin());
-        for (std::list<QPDFOutlineObjectHelper>::iterator iter =
+        for (std::vector<QPDFOutlineObjectHelper>::iterator iter =
                  outlines.begin();
              iter != outlines.end(); ++iter)
         {

include/qpdf/QPDFOutlineDocumentHelper.hh

@@ -28,8 +28,8 @@
 
 #include <qpdf/QPDF.hh>
 #include <map>
-#include <list>
 #include <set>
+#include <vector>
 
 #include <qpdf/DLL.h>
 
@@ -51,7 +51,7 @@ class QPDFOutlineDocumentHelper: public QPDFDocumentHelper
     bool hasOutlines();
 
     QPDF_DLL
-    std::list<QPDFOutlineObjectHelper> getTopLevelOutlines();
+    std::vector<QPDFOutlineObjectHelper> getTopLevelOutlines();
 
     // If the name is a name object, look it up in the /Dests key of
     // the document catalog. If the name is a string, look it up in
@@ -64,7 +64,7 @@ class QPDFOutlineDocumentHelper: public QPDFDocumentHelper
     // Return a list outlines that are known to target the specified
     // page
     QPDF_DLL
-    std::list<QPDFOutlineObjectHelper> getOutlinesForPage(QPDFObjGen const&);
+    std::vector<QPDFOutlineObjectHelper> getOutlinesForPage(QPDFObjGen const&);
 
     class Accessor
     {
@@ -95,11 +95,11 @@ class QPDFOutlineDocumentHelper: public QPDFDocumentHelper
         Members();
         Members(Members const&);
 
-        std::list<QPDFOutlineObjectHelper> outlines;
+        std::vector<QPDFOutlineObjectHelper> outlines;
         std::set<QPDFObjGen> seen;
         QPDFObjectHandle dest_dict;
         PointerHolder<QPDFNameTreeObjectHelper> names_dest;
-        std::map<QPDFObjGen, std::list<QPDFOutlineObjectHelper> > by_page;
+        std::map<QPDFObjGen, std::vector<QPDFOutlineObjectHelper> > by_page;
     };
 
     PointerHolder<Members> m;

include/qpdf/QPDFOutlineObjectHelper.hh

@@ -24,7 +24,7 @@
 
 #include <qpdf/QPDFObjectHelper.hh>
 #include <qpdf/QPDFObjGen.hh>
-#include <list>
+#include <vector>
 
 class QPDFOutlineDocumentHelper;
 
@@ -55,7 +55,7 @@ class QPDFOutlineObjectHelper: public QPDFObjectHelper
 
     // Return children as a list.
     QPDF_DLL
-    std::list<QPDFOutlineObjectHelper> getKids();
+    std::vector<QPDFOutlineObjectHelper> getKids();
 
     // Return the destination, regardless of whether it is named or
     // explicit and whether it is directly provided or in a GoTo
@@ -113,7 +113,7 @@ class QPDFOutlineObjectHelper: public QPDFObjectHelper
 
         QPDFOutlineDocumentHelper& dh;
         PointerHolder<QPDFOutlineObjectHelper> parent;
-        std::list<QPDFOutlineObjectHelper> kids;
+        std::vector<QPDFOutlineObjectHelper> kids;
     };
 
     PointerHolder<Members> m;

libqpdf/QPDFOutlineDocumentHelper.cc

@@ -42,7 +42,7 @@ QPDFOutlineDocumentHelper::hasOutlines()
     return ! this->m->outlines.empty();
 }
 
-std::list<QPDFOutlineObjectHelper>
+std::vector<QPDFOutlineObjectHelper>
 QPDFOutlineDocumentHelper::getTopLevelOutlines()
 {
     return this->m->outlines;
@@ -59,19 +59,19 @@ QPDFOutlineDocumentHelper::initializeByPage()
         QPDFOutlineObjectHelper oh = queue.front();
         queue.pop_front();
         this->m->by_page[oh.getDestPage().getObjGen()].push_back(oh);
-        std::list<QPDFOutlineObjectHelper> kids = oh.getKids();
+        std::vector<QPDFOutlineObjectHelper> kids = oh.getKids();
         queue.insert(queue.end(), kids.begin(), kids.end());
     }
 }
 
-std::list<QPDFOutlineObjectHelper>
+std::vector<QPDFOutlineObjectHelper>
 QPDFOutlineDocumentHelper::getOutlinesForPage(QPDFObjGen const& og)
 {
     if (this->m->by_page.empty())
     {
         initializeByPage();
     }
-    std::list<QPDFOutlineObjectHelper> result;
+    std::vector<QPDFOutlineObjectHelper> result;
     if (this->m->by_page.count(og))
     {
         result = this->m->by_page[og];

libqpdf/QPDFOutlineObjectHelper.cc

@@ -45,7 +45,7 @@ QPDFOutlineObjectHelper::getParent()
     return this->m->parent;
 }
 
-std::list<QPDFOutlineObjectHelper>
+std::vector<QPDFOutlineObjectHelper>
 QPDFOutlineObjectHelper::getKids()
 {
     return this->m->kids;

manual/qpdf-manual.xml

@@ -4314,6 +4314,16 @@ print "\n";
           higher level methods for tokenizing content streams.
          </para>
         </listitem>
+        <listitem>
+         <para>
+          Change
+          <function>QPDFOutlineDocumentHelper::getTopLevelOutlines</function>
+          and <function>QPDFOutlineObjectHelper::getKids</function> to
+          return a <type>std::vector</type> instead of a
+          <type>std::list</type> of
+          <classname>QPDFOutlineObjectHelper</classname> objects.
+         </para>
+        </listitem>
         <listitem>
          <para>
           When <command>qpdf --check</command> or <command>qpdf

qpdf/qpdf.cc

@@ -3493,9 +3493,9 @@ static void do_json_pages(QPDF& pdf, Options& o, JSON& j)
             "label", pldh.getLabelForPage(pageno).getJSON());
         JSON j_outlines = j_page.addDictionaryMember(
             "outlines", JSON::makeArray());
-        std::list<QPDFOutlineObjectHelper> outlines =
+        std::vector<QPDFOutlineObjectHelper> outlines =
             odh.getOutlinesForPage(page.getObjGen());
-        for (std::list<QPDFOutlineObjectHelper>::iterator oiter =
+        for (std::vector<QPDFOutlineObjectHelper>::iterator oiter =
                  outlines.begin();
              oiter != outlines.end(); ++oiter)
         {
@@ -3543,10 +3543,10 @@ static void do_json_page_labels(QPDF& pdf, Options& o, JSON& j)
 }
 
 static void add_outlines_to_json(
-    std::list<QPDFOutlineObjectHelper> outlines, JSON& j,
+    std::vector<QPDFOutlineObjectHelper> outlines, JSON& j,
     std::map<QPDFObjGen, int>& page_numbers)
 {
-    for (std::list<QPDFOutlineObjectHelper>::iterator iter = outlines.begin();
+    for (std::vector<QPDFOutlineObjectHelper>::iterator iter = outlines.begin();
          iter != outlines.end(); ++iter)
     {
         QPDFOutlineObjectHelper& ol = *iter;

qpdf/test_driver.cc

@@ -1805,9 +1805,9 @@ void runtest(int n, char const* filename1, char const* arg2)
         for (std::vector<QPDFPageObjectHelper>::iterator iter = pages.begin();
              iter != pages.end(); ++iter, ++pageno)
         {
-            std::list<QPDFOutlineObjectHelper> outlines =
+            std::vector<QPDFOutlineObjectHelper> outlines =
                 odh.getOutlinesForPage((*iter).getObjectHandle().getObjGen());
-            for (std::list<QPDFOutlineObjectHelper>::iterator oiter =
+            for (std::vector<QPDFOutlineObjectHelper>::iterator oiter =
                      outlines.begin();
                  oiter != outlines.end(); ++oiter)
             {