Treat all linearization errors as warnings

This also reverts the addition of a new checkLinearization that
distinguishes errors from warnings. There's no practical distinction
between what was considered an error and what was considered a
warning.

include/qpdf/QPDF.hh

@@ -477,15 +477,13 @@ class QPDF
     QPDF_DLL
     bool isLinearized();
 
-    // Performs various sanity checks on a linearized file.  Return
-    // true if no errors or warnings.  Otherwise, return false and
+    // Performs various sanity checks on a linearized file. Return
+    // true if no errors or warnings. Otherwise, return false and
     // output errors and warnings to std::cout or the output stream
-    // specified in a call to setOutputStreams.
+    // specified in a call to setOutputStreams. It is recommended for
+    // linearization errors to be treated as warnings.
     QPDF_DLL
     bool checkLinearization();
-    // Separately indicate whether there were errors or warnings.
-    QPDF_DLL
-    void checkLinearization(bool& errors, bool& warnings);
 
     // Calls checkLinearization() and, if possible, prints normalized
     // contents of some of the hints tables to std::cout or the output
@@ -1229,7 +1227,7 @@ class QPDF
     // methods to support linearization checking -- implemented in
     // QPDF_linearization.cc
     void readLinearizationData();
-    void checkLinearizationInternal(bool& errors, bool& warnings);
+    bool checkLinearizationInternal();
     void dumpLinearizationDataInternal();
     QPDFObjectHandle readHintStream(
         Pipeline&, qpdf_offset_t offset, size_t length);

libqpdf/QPDF_linearization.cc

@@ -65,25 +65,17 @@ load_vector_vector(BitStream& bit_stream,
 bool
 QPDF::checkLinearization()
 {
-    bool errors = false;
-    bool warnings = false;
-    checkLinearization(errors, warnings);
-    return (! (errors || warnings));
-}
-
-void
-QPDF::checkLinearization(bool& errors, bool& warnings)
-{
+    bool result = false;
     try
     {
 	readLinearizationData();
-	checkLinearizationInternal(errors, warnings);
+	result = checkLinearizationInternal();
     }
     catch (QPDFExc& e)
     {
 	*this->m->out_stream << e.what() << std::endl;
-        errors = true;
     }
+    return result;
 }
 
 bool
@@ -507,8 +499,8 @@ QPDF::readHGeneric(BitStream h, HGeneric& t)
     t.group_length = h.getBitsInt(32);                      // 4
 }
 
-void
-QPDF::checkLinearizationInternal(bool& any_errors, bool& any_warnings)
+bool
+QPDF::checkLinearizationInternal()
 {
     // All comments referring to the PDF spec refer to the spec for
     // version 1.4.
@@ -656,26 +648,34 @@ QPDF::checkLinearizationInternal(bool& any_errors, bool& any_warnings)
 
     // Report errors
 
-    any_errors = (! errors.empty());
-    any_warnings = (! warnings.empty());
+    bool result = true;
 
-    if (any_errors)
+    // Treat all linearization errors as warnings. Many of them occur
+    // in otherwise working files, so it's really misleading to treat
+    // them as errors. We'll hang onto the distinction in the code for
+    // now in case we ever have a chance to clean up the linearization
+    // code.
+    if (! errors.empty())
     {
+	result = false;
 	for (std::list<std::string>::iterator iter = errors.begin();
 	     iter != errors.end(); ++iter)
 	{
-	    *this->m->out_stream << "ERROR: " << (*iter) << std::endl;
+	    *this->m->out_stream << "WARNING: " << (*iter) << std::endl;
 	}
     }
 
-    if (any_warnings)
+    if (! warnings.empty())
     {
+	result = false;
 	for (std::list<std::string>::iterator iter = warnings.begin();
 	     iter != warnings.end(); ++iter)
 	{
 	    *this->m->out_stream << "WARNING: " << (*iter) << std::endl;
 	}
     }
+
+    return result;
 }
 
 qpdf_offset_t
@@ -1089,9 +1089,7 @@ QPDF::showLinearizationData()
     try
     {
 	readLinearizationData();
-        bool errors = false;
-        bool warnings = false;
-	checkLinearizationInternal(errors, warnings);
+	checkLinearizationInternal();
 	dumpLinearizationDataInternal();
     }
     catch (QPDFExc& e)

manual/qpdf-manual.xml

@@ -4314,6 +4314,14 @@ print "\n";
           higher level methods for tokenizing content streams.
          </para>
         </listitem>
+        <listitem>
+         <para>
+          When <command>qpdf --check</command> or <command>qpdf
+          --check-linearization</command> encounters a file with
+          linearization warnings but not errors, it now properly exits
+          with exit code 3 instead of 2.
+         </para>
+        </listitem>
        </itemizedlist>
       </listitem>
       <listitem>
@@ -4361,6 +4369,14 @@ print "\n";
           missing /Length keys in the encryption dictionary.
          </para>
         </listitem>
+        <listitem>
+         <para>
+          When <command>qpdf --check</command> or <command>qpdf
+          --check-linearization</command> encounters a file with
+          linearization warnings but not errors, it now properly exits
+          with exit code 3 instead of 2.
+         </para>
+        </listitem>
        </itemizedlist>
       </listitem>
       <listitem>
@@ -4462,10 +4478,9 @@ print "\n";
         </listitem>
         <listitem>
          <para>
-          A new version of
-          <function>QPDF::checkLinearization()</function> has been
-          added that indicates separately whether there were errors or
-          warnings.
+          All conditions previously reported by
+          <function>QPDF::checkLinearization()</function> as errors
+          are now presented as warnings.
          </para>
         </listitem>
        </itemizedlist>

qpdf/qpdf.cc

@@ -3210,15 +3210,10 @@ static void do_check(QPDF& pdf, Options& o, int& exit_code)
         if (pdf.isLinearized())
         {
             std::cout << "File is linearized\n";
-            bool lin_errors = false;
-            bool lin_warnings = false;
-            // any errors or warnings are reported by checkLinearization()
-            pdf.checkLinearization(lin_errors, lin_warnings);
-            if (lin_errors)
-            {
-                okay = false;
-            }
-            else if (lin_warnings)
+            // any errors or warnings are reported by
+            // checkLinearization(). We treat all issues reported here
+            // as warnings.
+            if (! pdf.checkLinearization())
             {
                 warnings = true;
             }
@@ -3796,22 +3791,15 @@ static void do_inspection(QPDF& pdf, Options& o)
     }
     if (o.check_linearization)
     {
-        bool lin_errors = false;
-        bool lin_warnings = false;
-        pdf.checkLinearization(lin_errors, lin_warnings);
-        if (lin_errors)
-        {
-            exit_code = EXIT_ERROR;
-        }
-        else if (lin_warnings && (exit_code != EXIT_ERROR))
-        {
-            exit_code = EXIT_WARNING;
-        }
-        else
+        if (pdf.checkLinearization())
         {
             std::cout << o.infilename << ": no linearization errors"
                       << std::endl;
         }
+        else if (exit_code != EXIT_ERROR)
+        {
+            exit_code = EXIT_WARNING;
+        }
     }
     if (o.show_linearization)
     {

qpdf/qtest/qpdf.test

@@ -1321,12 +1321,12 @@ $n_tests += 3;
 $td->runtest("bounds check linearization data 1",
              {$td->COMMAND => "qpdf --check linearization-bounds-1.pdf"},
              {$td->FILE => "linearization-bounds-1.out",
-              $td->EXIT_STATUS => 2},
+              $td->EXIT_STATUS => 3},
              $td->NORMALIZE_NEWLINES);
 $td->runtest("bounds check linearization data 2",
              {$td->COMMAND => "qpdf --check linearization-bounds-2.pdf"},
              {$td->FILE => "linearization-bounds-2.out",
-              $td->EXIT_STATUS => 2},
+              $td->EXIT_STATUS => 3},
              $td->NORMALIZE_NEWLINES);
 # Throws logic error, not bad_alloc
 $td->runtest("sanity check array size",
@@ -2855,7 +2855,7 @@ my @to_linearize =
      );
 
 $n_tests += @linearized_files + 6;
-$n_tests += (3 * @to_linearize * 5) + 8;
+$n_tests += (3 * @to_linearize * 5) + 6;
 
 foreach my $base (@linearized_files)
 {
@@ -2939,17 +2939,6 @@ foreach my $base (@to_linearize)
     }
 }
 
-# Verify that we get proper exit codes for files with only warnings
-$td->runtest("linearization warnings check",
-             {$td->COMMAND => "qpdf --check lin3.pdf"},
-             {$td->FILE => "lin3-check.out", $td->EXIT_STATUS => 3},
-             $td->NORMALIZE_NEWLINES);
-$td->runtest("linearization warnings check-linearization",
-             {$td->COMMAND => "qpdf --check-linearization lin3.pdf"},
-             {$td->FILE => "lin3-check-linearization.out",
-                  $td->EXIT_STATUS => 3},
-             $td->NORMALIZE_NEWLINES);
-
 show_ntests();
 # ----------
 $td->notify("--- Encryption Tests ---");

qpdf/qtest/qpdf/badlin1.out

@@ -1,5 +1,5 @@
-ERROR: first page object (/O) mismatch
-ERROR: space before first xref item (/T) mismatch (computed = 11777; file = 11771
+WARNING: first page object (/O) mismatch
+WARNING: space before first xref item (/T) mismatch (computed = 11777; file = 11771
 WARNING: end of first page section (/E) mismatch: /E = 1827; computed = 3889..3891
 WARNING: page 0 has shared identifier entries
 WARNING: page 0: shared object 62: in hint table but not computed list