Changed external functions to enable global installation

* up until now all external functions were locally installed to a specific XalanTransformer instance contained within a TransformationGuard instance
** this had to change as I planned to add a "execute-transformation" function based on TransformationGuard which would have led to recursive self-instantiation
** global external functions have to be thread-safe
* as global external function can not be provided with a reference to a transformation-specific FilesystemFacade instance, the working path is now determined using xalan::Locator
** currently using pointer arithmetics on XMLCh* to remove the "file://" prefix of the URI returned by locator->getSystemId(), may be unsafe
* added compilation unit for PlattformGuard as it now contains function installation in addition to plattform lifetime management

6 files changed, 34 insertions, 22 deletions

diff --git a/src/function/read_directory.cc b/src/function/read_directory.cc
index f155029..b13be2b 100644
--- a/src/function/read_directory.cc
+++ b/src/function/read_directory.cc
@@ -6,21 +6,27 @@
 #include <xercesc/dom/DOMText.hpp>
 
 #include "support/xerces_string_guard.h"
+#include "support/filesystem_context.h"
 
 namespace InputXSLT {
 
-FunctionReadDirectory::FunctionReadDirectory(const FilesystemContext& context):
-	fs_context_(context),
+FunctionReadDirectory::FunctionReadDirectory():
 	document_cache_(std::make_shared<DomDocumentCache>()) { }
 
 xalan::XObjectPtr FunctionReadDirectory::execute(
 	xalan::XPathExecutionContext& executionContext,
 	xalan::XalanNode*,
 	const xalan::XObjectPtr argument,
-	const xalan::Locator*
+	const xalan::Locator* locator
 ) const {
+	const FilesystemContext fs_context(
+		boost::filesystem::path(
+			xercesc::XMLString::transcode(locator->getSystemId() + 7)
+		).parent_path().string()
+	);
+
 	const boost::filesystem::path directoryPath(
-		this->fs_context_.resolve(argument->str())
+		fs_context.resolve(argument->str())
 	);
 
 	DomDocumentCache::item* const cachedDocument(
@@ -37,7 +43,7 @@ xalan::XObjectPtr FunctionReadDirectory::execute(
 		);
 
 		if ( boost::filesystem::is_directory(directoryPath) ) {
-			this->fs_context_.iterate(
+			fs_context.iterate(
 				argument->str(),
 				[&domDocument, &rootNode](const boost::filesystem::path& p) {
 				xercesc::DOMElement* const itemNode(
diff --git a/src/function/read_directory.h b/src/function/read_directory.h
index f4f7ec8..02a0305 100644
--- a/src/function/read_directory.h
+++ b/src/function/read_directory.h
@@ -9,14 +9,13 @@
 #include <memory>
 
 #include "common.h"
-#include "support/filesystem_context.h"
 #include "support/dom/document_cache.h"
 
 namespace InputXSLT {
 
 class FunctionReadDirectory : public xalan::Function {
 	public:
-		FunctionReadDirectory(const FilesystemContext&);
+		FunctionReadDirectory();
 
 		virtual xalan::XObjectPtr execute(
 			xalan::XPathExecutionContext&,
@@ -31,7 +30,6 @@ class FunctionReadDirectory : public xalan::Function {
 		bool operator==(const FunctionReadDirectory&) const            = delete;
 
 	private:
-		const FilesystemContext& fs_context_;
 		std::shared_ptr<DomDocumentCache> document_cache_;
 
 		const xalan::XalanDOMString& getError(xalan::XalanDOMString&) const;
diff --git a/src/function/read_file.cc b/src/function/read_file.cc
index f531191..7634d54 100644
--- a/src/function/read_file.cc
+++ b/src/function/read_file.cc
@@ -8,6 +8,7 @@
 #include "boost/filesystem/fstream.hpp"
 
 #include "support/xerces_string_guard.h"
+#include "support/filesystem_context.h"
 
 namespace {
 
@@ -24,18 +25,23 @@ inline std::string readFile(const boost::filesystem::path& filePath) {
 
 namespace InputXSLT {
 
-FunctionReadFile::FunctionReadFile(const FilesystemContext& context):
-	fs_context_(context),
+FunctionReadFile::FunctionReadFile():
 	document_cache_(std::make_shared<DomDocumentCache>()) { }
 
 xalan::XObjectPtr FunctionReadFile::execute(
 	xalan::XPathExecutionContext& executionContext,
 	xalan::XalanNode*,
 	const xalan::XObjectPtr argument,
-	const xalan::Locator*
+	const xalan::Locator* locator
 ) const {
+	const FilesystemContext fs_context(
+		boost::filesystem::path(
+			xercesc::XMLString::transcode(locator->getSystemId() + 7)
+		).parent_path().string()
+	);
+
 	const boost::filesystem::path filePath(
-		this->fs_context_.resolve(argument->str())
+		fs_context.resolve(argument->str())
 	);
 
 	DomDocumentCache::item* const cachedDocument(
diff --git a/src/function/read_file.h b/src/function/read_file.h
index 6f38e95..65746a5 100644
--- a/src/function/read_file.h
+++ b/src/function/read_file.h
@@ -9,14 +9,13 @@
 #include <string>
 
 #include "common.h"
-#include "support/filesystem_context.h"
 #include "support/dom/document_cache.h"
 
 namespace InputXSLT {
 
 class FunctionReadFile : public xalan::Function {
 	public:
-		FunctionReadFile(const FilesystemContext&);
+		FunctionReadFile();
 
 		virtual xalan::XObjectPtr execute(
 			xalan::XPathExecutionContext&,
@@ -31,7 +30,6 @@ class FunctionReadFile : public xalan::Function {
 		bool operator==(const FunctionReadFile&) const       = delete;
 
 	private:
-		const FilesystemContext& fs_context_;
 		std::shared_ptr<DomDocumentCache> document_cache_;
 
 		const xalan::XalanDOMString& getError(xalan::XalanDOMString&) const;
diff --git a/src/function/read_xml_file.cc b/src/function/read_xml_file.cc
index bf9ec2e..608e71a 100644
--- a/src/function/read_xml_file.cc
+++ b/src/function/read_xml_file.cc
@@ -9,6 +9,7 @@
 #include "boost/filesystem/fstream.hpp"
 
 #include "support/xerces_string_guard.h"
+#include "support/filesystem_context.h"
 
 namespace {
 
@@ -30,18 +31,23 @@ inline xercesc::DOMNode* importDocumentElement(
 
 namespace InputXSLT {
 
-FunctionReadXmlFile::FunctionReadXmlFile(const FilesystemContext& context):
-	fs_context_(context),
+FunctionReadXmlFile::FunctionReadXmlFile():
 	document_cache_(std::make_shared<DomDocumentCache>()) { }
 
 xalan::XObjectPtr FunctionReadXmlFile::execute(
 	xalan::XPathExecutionContext& executionContext,
 	xalan::XalanNode*,
 	const xalan::XObjectPtr argument,
-	const xalan::Locator*
+	const xalan::Locator* locator
 ) const {
+	const FilesystemContext fs_context(
+		boost::filesystem::path(
+			xercesc::XMLString::transcode(locator->getSystemId() + 7)
+		).parent_path().string()
+	);
+
 	const boost::filesystem::path filePath(
-		this->fs_context_.resolve(argument->str())
+		fs_context.resolve(argument->str())
 	);
 
 	DomDocumentCache::item* const cachedDocument(
diff --git a/src/function/read_xml_file.h b/src/function/read_xml_file.h
index 1df48fb..d7ef440 100644
--- a/src/function/read_xml_file.h
+++ b/src/function/read_xml_file.h
@@ -10,14 +10,13 @@
 #include <memory>
 
 #include "common.h"
-#include "support/filesystem_context.h"
 #include "support/dom/document_cache.h"
 
 namespace InputXSLT {
 
 class FunctionReadXmlFile : public xalan::Function {
 	public:
-		FunctionReadXmlFile(const FilesystemContext&);
+		FunctionReadXmlFile();
 
 		virtual xalan::XObjectPtr execute(
 			xalan::XPathExecutionContext&,
@@ -32,7 +31,6 @@ class FunctionReadXmlFile : public xalan::Function {
 		bool operator==(const FunctionReadXmlFile&) const          = delete;
 
 	private:
-		const FilesystemContext& fs_context_;
 		std::shared_ptr<DomDocumentCache> document_cache_;
 
 		const xalan::XalanDOMString& getError(xalan::XalanDOMString& result) const;