From: Mikko Rasa <tdb@tdb.fi>
Date: Sun, 10 Apr 2011 13:23:08 +0000 (+0000)
Subject: Add descendant_depth function
X-Git-Url: http://git.tdb.fi/?p=libs%2Fcore.git;a=commitdiff_plain;h=0875a4cbef5e6d664488d8af2c37b3b252856750

Add descendant_depth function
---

diff --git a/source/utils.cpp b/source/utils.cpp
index 8f06757..4036225 100644
--- a/source/utils.cpp
+++ b/source/utils.cpp
@@ -165,5 +165,21 @@ Path relative(const Path &path, const Path &base)
 	return result;
 }
 
+int descendant_depth(const Path &path, const Path &parent)
+{
+	Path::Iterator i=path.begin();
+	Path::Iterator j=parent.begin();
+	for(; (i!=path.end() && j!=parent.end() && *i==*j); ++i, ++j) ;
+
+	if(j!=parent.end())
+		return -1;
+	
+	int result = 0;
+	for(; i!=path.end(); ++i)
+		++result;
+
+	return result;
+}
+
 } // namespace FS
 } // namespace Msp
diff --git a/source/utils.h b/source/utils.h
index c582c22..6a4c55a 100644
--- a/source/utils.h
+++ b/source/utils.h
@@ -52,6 +52,10 @@ void rename(const Path &from, const Path &to);
 /// Makes a path relative to some base path.  That is, base/result==path.
 Path relative(const Path &path, const Path &base);
 
+/** Determines how many levels a path is below another.  Returns -1 if path is
+not a descendant of parent. */
+int descendant_depth(const Path &path, const Path &parent);
+
 } // namespace FS
 } // namespace Msp