[XML] Include file name in XML-related errors

Resolves #40

include/cantera/base/xml.h

@@ -579,8 +579,9 @@ public:
      * routine is called by the root XML_Node object.
      *
      * @param f   Input stream containing the ascii input file
+     * @param filename Name of the input file, used in error messages
      */
-    void build(std::istream& f);
+    void build(std::istream& f, const std::string& filename="[unknown]");
 
     //! Copy all of the information in the current XML_Node tree into the
     //! destination XML_Node tree, doing a union operation as we go
@@ -648,6 +649,10 @@ protected:
      */
     std::string m_value;
 
+    //! Name of the file from which this XML node was read. Only populated for
+    //! the root node.
+    std::string m_filename;
+
     //! Map containing an index between the node name and the
     //! pointer to the node
     /*!

src/base/application.cpp

@@ -220,7 +220,7 @@ XML_Node* Application::get_XML_File(const std::string& file, int debug)
     if (ext != ".xml" && ext != ".ctml") {
         // Assume that we are trying to open a cti file. Do the conversion to XML.
         std::stringstream phase_xml(ct2ctml_string(path));
-        x->build(phase_xml);
+        x->build(phase_xml, path);
     } else {
         x->build(path);
     }
@@ -245,7 +245,7 @@ XML_Node* Application::get_XML_from_string(const std::string& text)
         s << ct_string2ctml_string(text.substr(start));
     }
     entry.first = new XML_Node();
-    entry.first->build(s);
+    entry.first->build(s, "[string]");
     return entry.first;
 }
 

src/base/xml.cpp

@@ -31,13 +31,8 @@ protected:
      *
      * @param line Number number where the error occurred.
      */
-    XML_Error(int line=0) :
-        m_line(line),
-        m_msg("Error in XML file") {
-        if (line > 0) {
-            m_msg += fmt::format(" at line {}", line+1);
-        }
-        m_msg += ".\n";
+    XML_Error(const std::string& file, int line) {
+        m_msg = fmt::format("Error in XML file '{}' at line {}.\n", file, line);
     }
 
     virtual std::string getMessage() const {
@@ -48,9 +43,6 @@ protected:
     virtual ~XML_Error() throw() {
     }
 
-    //! Line number of the file
-    int m_line;
-
     //! String message for the error
     std::string m_msg;
 };
@@ -71,9 +63,9 @@ public:
      * @param  line       Line number where the error occurred.
      */
     XML_TagMismatch(const std::string& opentag, const std::string& closetag,
-                    int line=0) :
-        XML_Error(line) {
-        m_msg += "<" + opentag + "> paired with </" + closetag + ">.\n";
+                    const std::string& filename, int line) :
+        XML_Error(filename, line) {
+        m_msg += fmt::format("<{}> paired with </{}>.\n", opentag, closetag);
     }
 
     virtual std::string getClass() const {
@@ -98,8 +90,8 @@ public:
      * @param  line    Line number where the error occurred.
      */
     XML_NoChild(const XML_Node* p, const std::string& parent,
-                std::string child, int line=0) :
-        XML_Error(line) {
+                std::string child, const std::string& filename, int line) :
+        XML_Error(filename, line) {
         m_msg += fmt::format("The XML Node <{}> does not contain a required "
             "child node named <{}>.\nExisting children are named:\n",
             parent, child);
@@ -723,11 +715,12 @@ void XML_Node::build(const std::string& filename)
         throw CanteraError("XML_Node::build",
             "Unable to open file '{}' for reading.", filename);
     }
-    build(fin);
+    build(fin, filename);
 }
 
-void XML_Node::build(std::istream& f)
+void XML_Node::build(std::istream& f, const std::string& filename)
 {
+    m_filename = filename;
     XML_Reader r(f);
     XML_Node* node = this;
     bool first = true;
@@ -772,7 +765,8 @@ void XML_Node::build(std::istream& f)
             }
         } else {
             if (node->name() != nm.substr(1,nm.size()-1)) {
-                throw XML_TagMismatch(node->name(), nm.substr(1,nm.size()-1), lnum);
+                throw XML_TagMismatch(node->name(), nm.substr(1,nm.size()-1),
+                    root().m_filename, lnum);
             }
             node = node->parent();
         }
@@ -885,14 +879,16 @@ XML_Node& XML_Node::child(const std::string& aloc) const
             if (i != m_childindex.end()) {
                 return i->second->child(loc);
             } else {
-                throw XML_NoChild(this, m_name, cname, lineNumber());
+                throw XML_NoChild(this, m_name, cname, root().m_filename,
+                    lineNumber());
             }
         } else {
             auto i = m_childindex.find(loc);
             if (i != m_childindex.end()) {
                 return *(i->second);
             } else {
-                throw XML_NoChild(this, m_name, loc, lineNumber());
+                throw XML_NoChild(this, m_name, loc, root().m_filename,
+                    lineNumber());
             }
         }
     }

src/clib/ctxml.cpp

@@ -89,12 +89,7 @@ extern "C" {
         try {
             writelog("WARNING: xml_build called. Use get_XML_File instead.");
             string path = findInputFile(file);
-            ifstream f(path);
-            if (!f) {
-                throw CanteraError("xml_build",
-                                   "file "+string(file)+" not found.");
-            }
-            XmlCabinet::item(i).build(f);
+            XmlCabinet::item(i).build(path);
             return 0;
         } catch (...) {
             return handleAllExceptions(-1, ERR);

src/oneD/OneDim.cpp

@@ -421,7 +421,7 @@ void OneDim::save(const std::string& fname, std::string id,
     XML_Node root("ctml");
     ifstream fin(fname);
     if (fin) {
-        root.build(fin);
+        root.build(fin, fname);
         // Remove existing solution with the same id
         XML_Node* same_ID = root.findID(id);
         if (same_ID) {