fix-qdf: accept optional output file (fixes #1330)

Jay Berkenbilt
1 parent 9cf96201
Showing 6 changed files with 83 additions and 21 deletions
ChangeLog
manual/fix-qdf.1.in
manual/qdf.rst
manual/release-notes.rst
qpdf/fix-qdf.cc
qpdf/qtest/fix-qdf.test
+2025-02-02  Jay Berkenbilt  <ejb@ql.org>
+
+	* Have fix-qdf accept a second argument, interpreted as the output
+	file. Fixes #1330.
+
 2024-02-01  M Holger  <m.holger@qpdf.org>
  
 	* Bug fix: in qpdf CLI / QPDFJob throw a QPDFUsage exception if a
@@ -3,9 +3,11 @@
 fix-qdf \- repair PDF files in QDF form after editing
 .SH SYNOPSIS
 .B fix-qdf
-< \fIinfilename\fR > \fIoutfilename\fR
+[\fIinfilename\fR [\fIoutfilename\fR]]
 .SH DESCRIPTION
-The fix-qdf program is part of the qpdf package.
+The fix-qdf program is part of the qpdf package. With no arguments,
+fix-qdf reads from standard input and writes to standard output. With
+one argument, it reads from that file and writes to standard output.
 .PP
 The fix-qdf program reads a PDF file in QDF form and writes out
 the same file with stream lengths, cross-reference table entries, and
@@ -23,10 +23,18 @@ files are full of offset and length information that makes it hard to
 add or remove data. A QDF file is organized in a manner such that, if
 edits are kept within certain constraints, the
 :command:`fix-qdf` program, distributed with qpdf, is
-able to restore edited files to a correct state. The
-:command:`fix-qdf` program takes no command-line
-arguments. It reads a possibly edited QDF file from standard input and
-writes a repaired file to standard output.
+able to restore edited files to a correct state.
+
+.. code-block:: bash
+
+  fix-qdf [infilename [outfilename]]
+
+With no arguments, :command:`fix-qdf` reads the possibly-edited QDF
+file from standard input and writes a repaired file to standard
+output. You can also specify the input and output files as
+command-line arguments. With one argument, the argument is taken as an
+input file. With two arguments, the first argument is an input file,
+and the second is an output file.
  
 For another way to work with PDF files in an editor, see :ref:`json`.
 Using qpdf JSON format allows you to edit the PDF file semantically
@@ -38,6 +38,14 @@ Planned changes for future 12.x (subject to change):
  
 .. x.y.z: not yet released
  
+11.10.0: not yet released
+  - CLI Enhancements
+
+    - The :command:`fix-qdf` command now allows an output file to be
+      specified as an optional second argument. This is useful for
+      environments in which writing a binary file to standard output
+      doesn't work (such as PowerShell 5).
+
 11.9.1: June 7, 2024
   - Bug Fixes
  
@@ -4,17 +4,20 @@
 #include <qpdf/QUtil.hh>
 #include <cstdio>
 #include <cstring>
+#include <fstream>
 #include <iostream>
 #include <regex>
 #include <string_view>
  
+using namespace std::literals;
 static char const* whoami = nullptr;
  
 static void
 usage()
 {
-    std::cerr << "Usage: " << whoami << " [filename]" << std::endl;
-    exit(2);
+    std::cerr << "Usage: " << whoami << " [infilename [outfilename]]" << std::endl
+              << "infilename defaults to standard output" << std::endl
+              << "outfilename defaults to standard output" << std::endl;
 }
  
 class QdfFixer
@@ -373,27 +376,44 @@ realmain(int argc, char* argv[])
     whoami = QUtil::getWhoami(argv[0]);
     QUtil::setLineBuf(stdout);
     char const* filename = nullptr;
-    if (argc > 2) {
+    char const* outfilename = nullptr;
+    if (argc > 3) {
         usage();
     } else if ((argc > 1) && (strcmp(argv[1], "--version") == 0)) {
         std::cout << whoami << " from qpdf version " << QPDF::QPDFVersion() << std::endl;
         return 0;
     } else if ((argc > 1) && (strcmp(argv[1], "--help") == 0)) {
         usage();
-    } else if (argc == 2) {
+    } else if (argc >= 2) {
         filename = argv[1];
+        if (argc == 3) {
+            outfilename = argv[2];
+        }
     }
-    std::string input;
-    if (filename == nullptr) {
-        filename = "standard input";
-        QUtil::binary_stdin();
-        input = QUtil::read_file_into_string(stdin);
-    } else {
-        input = QUtil::read_file_into_string(filename);
+    try {
+        std::string input;
+        if (filename == nullptr) {
+            filename = "standard input";
+            QUtil::binary_stdin();
+            input = QUtil::read_file_into_string(stdin);
+        } else {
+            input = QUtil::read_file_into_string(filename);
+        }
+        std::unique_ptr<std::ofstream> out = nullptr;
+        if (outfilename) {
+            out = std::make_unique<std::ofstream>(outfilename, std::ios::binary);
+            if (out->fail()) {
+                QUtil::throw_system_error("open "s + outfilename);
+            }
+        } else {
+            QUtil::binary_stdout();
+        }
+        QdfFixer qf(filename, out ? *out : std::cout);
+        qf.processLines(input);
+    } catch (std::exception& e) {
+        std::cerr << whoami << ": error: " << e.what() << std::endl;
+        exit(qpdf_exit_error);
     }
-    QUtil::binary_stdout();
-    QdfFixer qf(filename, std::cout);
-    qf.processLines(input);
     return 0;
 }
  
@@ -14,7 +14,7 @@ cleanup();
  
 my $td = new TestDriver('fix-qdf');
  
-my $n_tests = 5;
+my $n_tests = 11;
  
 for (my $n = 1; $n <= 2; ++$n)
 {
@@ -23,6 +23,15 @@ for (my $n = 1; $n &lt;= 2; ++$n)
                  {$td->FILE => "fix$n.qdf.out",
                   $td->EXIT_STATUS => 0});
  
+    $td->runtest("fix-qdf $n with named output",
+                 {$td->COMMAND => "fix-qdf fix$n.qdf a.pdf"},
+                 {$td->STRING => "",
+                  $td->EXIT_STATUS => 0});
+
+    $td->runtest("check fix-qdf $n output",
+                 {$td->FILE => "a.pdf"},
+                 {$td->FILE => "fix$n.qdf.out"});
+
     $td->runtest("identity fix-qdf $n",
                  {$td->COMMAND => "fix-qdf fix$n.qdf.out"},
                  {$td->FILE => "fix$n.qdf.out",
@@ -54,5 +63,15 @@ $td-&gt;runtest(&quot;fix-qdf with big object stream&quot;, # &gt; 255 objects in a stream
              {$td->FILE => "big-ostream.pdf",
               $td->EXIT_STATUS => 0});
  
+$td->runtest("fix-qdf error opening input",
+             {$td->COMMAND => "fix-qdf /does/not/exist/potato.pdf"},
+             {$td->REGEXP => "^fix-qdf: error: open .*/does/not/exist/potato.pdf: .*",
+              $td->EXIT_STATUS => 2});
+
+$td->runtest("fix-qdf error opening output", # > 255 objects in a stream
+             {$td->COMMAND => "fix-qdf fix1.qdf /does/not/exist/salad.pdf"},
+             {$td->REGEXP => "^fix-qdf: error: open .*/does/not/exist/salad.pdf: .*",
+              $td->EXIT_STATUS => 2});
+
 cleanup();
 $td->report($n_tests);