From 598268f6ade9fef4e18af211e77eb4e28c1ce2dc Mon Sep 17 00:00:00 2001
From: Jay Berkenbilt <ejb@ql.org>
Date: Tue, 2 Jul 2024 09:14:21 -0400
Subject: [PATCH] Add setMaxWarnings rather than using conditional compilation

---
 ChangeLog            | 11 +++++++++++
 fuzz/qpdf_fuzzer.cc  |  1 +
 include/qpdf/QPDF.hh |  5 +++++
 libqpdf/QPDF.cc      | 13 ++++++++-----
 4 files changed, 25 insertions(+), 5 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 4d6b8b5e..1eb89d74 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2024-07-02  Jay Berkenbilt  <ejb@ql.org>
+
+	* Add QPDF::setMaxWarnings to set the maximum of warnings before
+	warning suppression.
+
+	* Add additional options to Pl_DCT construction to limit sizes and
+	memory usage of compression. These are generally exposed but are
+	primarily intended to support fuzz tests, which have explicit
+	memory limits that are smaller than what is commonly seen in the
+	wild with PDF files.
+
 2024-06-07  Jay Berkenbilt  <ejb@ql.org>
 
 	* 11.9.1: release
diff --git a/fuzz/qpdf_fuzzer.cc b/fuzz/qpdf_fuzzer.cc
index d676e8cb..20073d28 100644
--- a/fuzz/qpdf_fuzzer.cc
+++ b/fuzz/qpdf_fuzzer.cc
@@ -57,6 +57,7 @@ FuzzHelper::getQpdf()
     auto is =
         std::shared_ptr<InputSource>(new BufferInputSource("fuzz input", &this->input_buffer));
     auto qpdf = QPDF::create();
+    qpdf->setMaxWarnings(20);
     qpdf->processInputSource(is);
     return qpdf;
 }
diff --git a/include/qpdf/QPDF.hh b/include/qpdf/QPDF.hh
index c83bcb0b..0044e58a 100644
--- a/include/qpdf/QPDF.hh
+++ b/include/qpdf/QPDF.hh
@@ -228,6 +228,10 @@ class QPDF
     QPDF_DLL
     void setSuppressWarnings(bool);
 
+    // Set the maximum number of warnings to output. Subsequent warnings are suppressed.
+    QPDF_DLL
+    void setMaxWarnings(int);
+
     // By default, QPDF will try to recover if it finds certain types of errors in PDF files.  If
     // turned off, it will throw an exception on the first such problem it finds without attempting
     // recovery.
@@ -1497,6 +1501,7 @@ class QPDF
         bool provided_password_is_hex_key{false};
         bool ignore_xref_streams{false};
         bool suppress_warnings{false};
+        int max_warnings{0};
         bool attempt_recovery{true};
         bool check_mode{false};
         std::shared_ptr<EncryptionParameters> encp;
diff --git a/libqpdf/QPDF.cc b/libqpdf/QPDF.cc
index 52fc1ce2..af2811fc 100644
--- a/libqpdf/QPDF.cc
+++ b/libqpdf/QPDF.cc
@@ -331,6 +331,12 @@ QPDF::setSuppressWarnings(bool val)
     m->suppress_warnings = val;
 }
 
+void
+QPDF::setMaxWarnings(int val)
+{
+    m->suppress_warnings = val;
+}
+
 void
 QPDF::setAttemptRecovery(bool val)
 {
@@ -500,14 +506,11 @@ QPDF::warn(QPDFExc const& e)
 {
     m->warnings.push_back(e);
     if (!m->suppress_warnings) {
-// QXXXQ
-#ifdef QPDF_OSS_FUZZ
-        if (m->warnings.size() > 20) {
-            *m->log->getWarn() << "WARNING: too many warnings - additional warnings surpressed\n";
+        if (m->max_warnings > 0 && m->warnings.size() > 20) {
+            *m->log->getWarn() << "WARNING: too many warnings - additional warnings suppressed\n";
             m->suppress_warnings = true;
             return;
         }
-#endif
         *m->log->getWarn() << "WARNING: " << m->warnings.back().what() << "\n";
     }
 }