Add 'header' class, for generic ALTA header parsing.

sources/core/common.cpp

 /* ALTA --- Analysis of Bidirectional Reflectance Distribution Functions
 
    Copyright (C) 2014 CNRS
-   Copyright (C) 2013, 2014 Inria
+   Copyright (C) 2013, 2014, 2015 Inria
 
    This file is part of ALTA.
 
@@ -22,6 +22,9 @@
 #include <unistd.h>
 #endif
 
+#include <iostream>
+
+
 double norm(const vec& a)
 {
 	double norm = 0.0 ;
@@ -179,3 +182,49 @@ unsigned int timer::current_time() const
 	return (unsigned int)_time.tv_sec;
 #endif
 }
+
+
+header::header(std::istream& input)
+{
+	while(input.good())
+	{
+		if (input.peek() == '#')
+		{
+			input.get();																// consume the hash sign
+
+			std::string line;
+			std::getline(input, line);
+			std::stringstream linestream(line);
+
+			// Lines starting with '# ' are real comments and we ignore them.
+			// Others are key/value associations that we want to use.
+			if (linestream.peek() != ' ')
+			{
+				 std::string key, rest;
+				 linestream >> key;
+				 if (!key.empty())
+				 {
+					 if (key == "ALTA")
+					 {
+						 std::string first, second;
+						 linestream >> first >> second;
+						 if (second == "HEADER")
+						 {
+							 if (first == "END")
+								 break;
+							 else
+								 _kind = first;
+						 }
+					 }
+					 else
+					 {
+						 getline(linestream, rest);
+						 _alist[key] = rest;
+					 }
+				 }
+			}
+		}
+		// The first non-comment line terminates the header.
+		else break;
+	}
+}

sources/core/common.h

@@ -29,6 +29,9 @@
 #include <cstring>
 #include <algorithm>
 
+#include <string>
+#include <map>
+
 #ifdef OLD
 /*! \brief A core implementation of a vector of double.
  *  \ingroup core
@@ -386,6 +389,37 @@ class timer
         unsigned int _elapsed;
 };
 
+
+// Reading the ALTA header of data and function files.
+
+
+// Key/value association list.
+class header
+{
+	public:
+		//! \brief Read the ALTA header on INPUT.
+		header(std::istream &input);
+
+		//! \brief Return the type of this header--i.e., the "FOO" in
+		// "#ALTA FOO HEADER".
+		const std::string& kind() const
+		{
+			return _kind;
+		}
+
+		//! \brief Return the value associated with KEY in this header.
+		const std::string& operator[](const std::string& key)
+		{
+			return _alist[key];
+		}
+
+	protected:
+		std::string _kind;
+		std::map<std::string, std::string> _alist;
+};
+
+
+
 
 // I/O error handling in user interfaces.
 

sources/core/data_storage.cpp

@@ -19,48 +19,6 @@
 # include <endian.h>
 #endif
 
-// Key/value association list.
-typedef std::map<std::string, std::string> alist;
-
-// Read the ALTA header on INPUT and fill in RESULT as a list of key/value
-// pairs.
-static void read_header(std::istream &input, alist &result)
-{
-	while(input.good())
-	{
-		if (input.peek() == '#')
-		{
-			input.get();																// consume the hash sign
-
-			std::string line;
-			std::getline(input, line);
-			std::stringstream linestream(line);
-
-			// Lines starting with '# ' are real comments and we ignore them.
-			// Others are key/value associations that we want to use.
-			if (linestream.peek() != ' ')
-			{
-				 std::string key, rest;
-				 linestream >> key;
-				 if (!key.empty())
-				 {
-					 getline(linestream, rest);
-					 if (key == "ALTA" && rest == "END HEADER")
-					 {
-						 break;
-					 }
-					 else
-					 {
-						 result[key] = rest;
-					 }
-				 }
-			}
-		}
-		// The first non-comment line terminates the header.
-		else break;
-	}
-}
-
 void vertical_segment::load_data_from_text(std::istream& input,
 																					 vertical_segment& result,
 																					 const arguments& args)
@@ -71,8 +29,7 @@ void vertical_segment::load_data_from_text(std::istream& input,
 	result._nX = 0 ; result._nY = 0 ;
 	std::vector<int> vs ; int current_vs = 0 ;
 
-	alist header;
-	read_header(input, header);
+	header header(input);
 
 	{
 		std::stringstream dim(header["DIM"]);