Allow -DNO_GET_ENVIRONMENT to avoid GetEnvironmentVariable

If NO_GET_ENVIRONMENT is #defined at compile time on Windows, do not
call GetEnvironmentVariable.  QUtil::get_env will always return
false.  This option is not available through configure.  This was
added to support a specific user's requirements to avoid calling
GetEnvironmentVariable from the Windows API.  Nothing in qpdf outside
the test coverage system in qtest relies on QUtil::get_env.

ChangeLog

@@ -1,5 +1,12 @@
 2013-11-29  Jay Berkenbilt  <ejb@ql.org>
 
+	* If NO_GET_ENVIRONMENT is #defined, for Windows only,
+	QUtil::get_env will always return false.  This was added to
+	support a user who needs to avoid calling GetEnvironmentVariable
+	from the Windows API.  QUtil::get_env is not used for any
+	functionality in qpdf and exists only to support the test suite
+	including test coverage support with QTC (part of qtest).
+
 	* Add /FS to msvc builds to allow parallel builds to work with
 	Visual C++ 2013.
 

examples/pdf-double-page-size.cc

@@ -51,6 +51,15 @@ int main(int argc, char* argv[])
 	whoami += 3;
     }
 
+    // For test suite
+    bool static_id = false;
+    if ((argc > 1) && (strcmp(argv[1], " --static-id") == 0))
+    {
+        static_id = true;
+        --argc;
+        ++argv;
+    }
+
     if (! ((argc == 3) || (argc == 4)))
     {
 	usage();
@@ -88,7 +97,7 @@ int main(int argc, char* argv[])
 
 	// Write out a new file
 	QPDFWriter w(qpdf, outfilename);
-	if (QUtil::get_env("IN_TESTSUITE"))
+	if (static_id)
 	{
 	    // For the test suite, uncompress streams and use static
 	    // IDs.

examples/pdf-invert-images.cc

@@ -70,6 +70,15 @@ int main(int argc, char* argv[])
 	whoami += 3;
     }
 
+    // For test suite
+    bool static_id = false;
+    if ((argc > 1) && (strcmp(argv[1], " --static-id") == 0))
+    {
+        static_id = true;
+        --argc;
+        ++argv;
+    }
+
     if (! ((argc == 3) || (argc == 4)))
     {
 	usage();
@@ -149,7 +158,7 @@ int main(int argc, char* argv[])
 
 	// Write out a new file
 	QPDFWriter w(qpdf, outfilename);
-	if (QUtil::get_env("IN_TESTSUITE"))
+	if (static_id)
 	{
 	    // For the test suite, uncompress streams and use static
 	    // IDs.

examples/qtest/double-page-size.test

@@ -12,7 +12,8 @@ my $td = new TestDriver('double-page-size');
 cleanup();
 
 $td->runtest("double page size",
-	     {$td->COMMAND => "pdf-double-page-size in.pdf a.pdf"},
+	     {$td->COMMAND => ['pdf-double-page-size', ' --static-id',
+                               'in.pdf', 'a.pdf']},
 	     {$td->STRING =>
 		  "pdf-double-page-size: new file written to a.pdf\n",
 	      $td->EXIT_STATUS => 0},

examples/qtest/invert-images.test

@@ -12,7 +12,8 @@ my $td = new TestDriver('invert-images');
 cleanup();
 
 $td->runtest("double page size",
-	     {$td->COMMAND => "pdf-invert-images in.pdf a.pdf"},
+	     {$td->COMMAND => ['pdf-invert-images', ' --static-id',
+                               'in.pdf', 'a.pdf']},
 	     {$td->STRING =>
 		  "pdf-invert-images: new file written to a.pdf\n",
 	      $td->EXIT_STATUS => 0},

libqpdf/QUtil.cc

@@ -7,6 +7,7 @@
 #include <cmath>
 #include <iomanip>
 #include <sstream>
+#include <stdexcept>
 #include <stdio.h>
 #include <errno.h>
 #include <ctype.h>
@@ -262,6 +263,9 @@ QUtil::get_env(std::string const& var, std::string* value)
 {
     // This was basically ripped out of wxWindows.
 #ifdef _WIN32
+# ifdef NO_GET_ENVIRONMENT
+    return false;
+# else
     // first get the size of the buffer
     DWORD len = ::GetEnvironmentVariable(var.c_str(), NULL, 0);
     if (len == 0)
@@ -279,6 +283,7 @@ QUtil::get_env(std::string const& var, std::string* value)
     }
 
     return true;
+# endif
 #else
     char* p = getenv(var.c_str());
     if (p == 0)