Code tidy : replace 0 with nullptr or true

15 files changed, 26 insertions, 25 deletions

diff --git a/examples/pdf-attach-file.cc b/examples/pdf-attach-file.cc
index eb12a002..c04f5b9f 100644
--- a/examples/pdf-attach-file.cc
+++ b/examples/pdf-attach-file.cc
@@ -15,7 +15,7 @@
 // the use of the qpdf literal syntax introduced in qpdf 10.6.
 //
 
-static char const* whoami = 0;
+static char const* whoami = nullptr;
 
 static void
 usage(std::string const& msg)
@@ -167,11 +167,11 @@ main(int argc, char* argv[])
 {
     whoami = QUtil::getWhoami(argv[0]);
 
-    char const* infilename = 0;
-    char const* password = 0;
-    char const* attachment = 0;
-    char const* outfilename = 0;
-    char const* mimetype = 0;
+    char const* infilename = nullptr;
+    char const* password = nullptr;
+    char const* attachment = nullptr;
+    char const* outfilename = nullptr;
+    char const* mimetype = nullptr;
 
     auto check_arg = [](char const* arg, std::string const& msg) {
         if (arg == nullptr) {
diff --git a/examples/pdf-bookmarks.cc b/examples/pdf-bookmarks.cc
index f6c91b21..1cee51ef 100644
--- a/examples/pdf-bookmarks.cc
+++ b/examples/pdf-bookmarks.cc
@@ -14,7 +14,7 @@
 //
 // Ignore calls to QTC::TC - they are for qpdf CI testing only.
 
-static char const* whoami = 0;
+static char const* whoami = nullptr;
 static enum { st_none, st_numbers, st_lines } style = st_none;
 static bool show_open = false;
 static bool show_targets = false;
diff --git a/examples/pdf-count-strings.cc b/examples/pdf-count-strings.cc
index 85e05a5f..c762e7f8 100644
--- a/examples/pdf-count-strings.cc
+++ b/examples/pdf-count-strings.cc
@@ -15,7 +15,7 @@
 #include <qpdf/QPDFPageObjectHelper.hh>
 #include <qpdf/QUtil.hh>
 
-static char const* whoami = 0;
+static char const* whoami = nullptr;
 
 void
 usage()
diff --git a/examples/pdf-create.cc b/examples/pdf-create.cc
index 785021da..f730b743 100644
--- a/examples/pdf-create.cc
+++ b/examples/pdf-create.cc
@@ -20,7 +20,7 @@
 #include <stdlib.h>
 #include <string.h>
 
-static char const* whoami = 0;
+static char const* whoami = nullptr;
 
 // This is a simple StreamDataProvider that writes image data for an
 // orange square of the given width and height.
diff --git a/examples/pdf-custom-filter.cc b/examples/pdf-custom-filter.cc
index e7877bea..2ea5fd42 100644
--- a/examples/pdf-custom-filter.cc
+++ b/examples/pdf-custom-filter.cc
@@ -37,7 +37,7 @@
 // of running this example on test files that are specifically crafted
 // for it.
 
-static char const* whoami = 0;
+static char const* whoami = nullptr;
 
 class Pl_XOR: public Pipeline
 {
@@ -447,8 +447,8 @@ main(int argc, char* argv[])
 {
     whoami = QUtil::getWhoami(argv[0]);
 
-    char const* infilename = 0;
-    char const* outfilename = 0;
+    char const* infilename = nullptr;
+    char const* outfilename = nullptr;
     bool decode_specialized = false;
     for (int i = 1; i < argc; ++i) {
         if (strcmp(argv[i], "--decode-specialized") == 0) {
diff --git a/examples/pdf-double-page-size.cc b/examples/pdf-double-page-size.cc
index f0f86d02..fb0584e9 100644
--- a/examples/pdf-double-page-size.cc
+++ b/examples/pdf-double-page-size.cc
@@ -8,7 +8,7 @@
 #include <stdlib.h>
 #include <string.h>
 
-static char const* whoami = 0;
+static char const* whoami = nullptr;
 
 void
 usage()
diff --git a/examples/pdf-filter-tokens.cc b/examples/pdf-filter-tokens.cc
index ccacc8c2..c9a71e64 100644
--- a/examples/pdf-filter-tokens.cc
+++ b/examples/pdf-filter-tokens.cc
@@ -18,7 +18,7 @@
 #include <qpdf/QPDFWriter.hh>
 #include <qpdf/QUtil.hh>
 
-static char const* whoami = 0;
+static char const* whoami = nullptr;
 
 void
 usage()
diff --git a/examples/pdf-invert-images.cc b/examples/pdf-invert-images.cc
index 94392ac3..9ffb9c1f 100644
--- a/examples/pdf-invert-images.cc
+++ b/examples/pdf-invert-images.cc
@@ -9,7 +9,7 @@
 #include <stdlib.h>
 #include <string.h>
 
-static char const* whoami = 0;
+static char const* whoami = nullptr;
 
 void
 usage()
@@ -142,7 +142,8 @@ main(int argc, char* argv[])
                 // pipeStreamData with a null pipeline to determine
                 // whether the image is filterable.  Directly inspect
                 // keys to determine the image type.
-                if (image.pipeStreamData(0, qpdf_ef_compress, qpdf_dl_all) &&
+                if (image.pipeStreamData(
+                        nullptr, qpdf_ef_compress, qpdf_dl_all) &&
                     color_space.isNameAndEquals("/DeviceGray") &&
                     bits_per_component.isInteger() &&
                     (bits_per_component.getIntValue() == 8)) {
diff --git a/examples/pdf-mod-info.cc b/examples/pdf-mod-info.cc
index 2b8e3c47..fa49738b 100644
--- a/examples/pdf-mod-info.cc
+++ b/examples/pdf-mod-info.cc
@@ -11,7 +11,7 @@
 #include <string.h>
 
 static char const* version = "1.1";
-static char const* whoami = 0;
+static char const* whoami = nullptr;
 
 void
 usage()
@@ -77,8 +77,8 @@ main(int argc, char* argv[])
         exit(0);
     }
 
-    char* fl_in = 0;
-    char* fl_out = 0;
+    char* fl_in = nullptr;
+    char* fl_out = nullptr;
     std::string cur_key;
 
     for (int i = 1; i < argc; ++i) {
diff --git a/examples/pdf-name-number-tree.cc b/examples/pdf-name-number-tree.cc
index 939105e9..381085ba 100644
--- a/examples/pdf-name-number-tree.cc
+++ b/examples/pdf-name-number-tree.cc
@@ -6,7 +6,7 @@
 #include <cstring>
 #include <iostream>
 
-static char const* whoami = 0;
+static char const* whoami = nullptr;
 
 void
 usage()
diff --git a/examples/pdf-npages.cc b/examples/pdf-npages.cc
index f430935c..3d34d489 100644
--- a/examples/pdf-npages.cc
+++ b/examples/pdf-npages.cc
@@ -5,7 +5,7 @@
 #include <qpdf/QPDF.hh>
 #include <qpdf/QUtil.hh>
 
-static char const* whoami = 0;
+static char const* whoami = nullptr;
 
 void
 usage()
diff --git a/examples/pdf-overlay-page.cc b/examples/pdf-overlay-page.cc
index 594f139e..d055d279 100644
--- a/examples/pdf-overlay-page.cc
+++ b/examples/pdf-overlay-page.cc
@@ -12,7 +12,7 @@
 // --overlay and --underlay options provide a more general version of
 // this capability.
 
-static char const* whoami = 0;
+static char const* whoami = nullptr;
 
 void
 usage()
diff --git a/examples/pdf-parse-content.cc b/examples/pdf-parse-content.cc
index 6bc94da2..481633e6 100644
--- a/examples/pdf-parse-content.cc
+++ b/examples/pdf-parse-content.cc
@@ -8,7 +8,7 @@
 #include <qpdf/QPDFPageObjectHelper.hh>
 #include <qpdf/QUtil.hh>
 
-static char const* whoami = 0;
+static char const* whoami = nullptr;
 
 void
 usage()
diff --git a/examples/pdf-set-form-values.cc b/examples/pdf-set-form-values.cc
index cc328cf3..1398c0dd 100644
--- a/examples/pdf-set-form-values.cc
+++ b/examples/pdf-set-form-values.cc
@@ -8,7 +8,7 @@
 #include <stdlib.h>
 #include <string.h>
 
-static char const* whoami = 0;
+static char const* whoami = nullptr;
 
 void
 usage()
diff --git a/examples/qpdf-job.cc b/examples/qpdf-job.cc
index b71b612a..614abbe6 100644
--- a/examples/qpdf-job.cc
+++ b/examples/qpdf-job.cc
@@ -8,7 +8,7 @@
 // This program is a simple demonstration of different ways to use the
 // QPDFJob API.
 
-static char const* whoami = 0;
+static char const* whoami = nullptr;
 
 static void
 usage()