From: Mikko Rasa <tdb@tdb.fi>
Date: Fri, 3 May 2013 09:47:51 +0000 (+0300)
Subject: Throw an exception for nonsensical arguments in some FS functions
X-Git-Url: http://git.tdb.fi/?a=commitdiff_plain;h=c4bebb877ec98d518bf02152ca81930e18eda6a7;p=libs%2Fcore.git

Throw an exception for nonsensical arguments in some FS functions
---

diff --git a/source/fs/utils.cpp b/source/fs/utils.cpp
index 2bfd1bf..ed1ca0a 100644
--- a/source/fs/utils.cpp
+++ b/source/fs/utils.cpp
@@ -71,6 +71,9 @@ Path fix_case(const Path &path)
 
 Path relative(const Path &path, const Path &base)
 {
+	if(path.is_absolute()!=base.is_absolute())
+		throw invalid_argument("FS::relative");
+
 	Path::Iterator i = path.begin();
 	Path::Iterator j = base.begin();
 	for(; (i!=path.end() && j!=base.end() && *i==*j); ++i, ++j) ;
@@ -96,6 +99,9 @@ Path common_ancestor(const Path &path1, const Path &path2)
 
 int descendant_depth(const Path &path, const Path &parent)
 {
+	if(path.is_absolute()!=parent.is_absolute())
+		throw invalid_argument("FS::descendant_depth");
+
 	Path::Iterator i = path.begin();
 	Path::Iterator j = parent.begin();
 	for(; (i!=path.end() && j!=parent.end() && *i==*j); ++i, ++j) ;
diff --git a/source/fs/utils.h b/source/fs/utils.h
index a52e37d..e518d35 100644
--- a/source/fs/utils.h
+++ b/source/fs/utils.h
@@ -35,14 +35,15 @@ void unlink(const Path &path);
 /// Renames a file.  Existing file, if any, is overwritten.
 void rename(const Path &from, const Path &to);
 
-/// Makes a path relative to some base path.  That is, base/result==path.
+/** Makes a path relative to some base path.  That is, base/result==path.  Both
+paths must be either absolute or relative. */
 Path relative(const Path &path, const Path &base);
 
 /// Returns the longest prefix shared by both paths.
 Path common_ancestor(const Path &, const Path &);
 
 /** Determines how many levels a path is below another.  Returns -1 if path is
-not a descendant of parent. */
+not a descendant of parent.  Both paths must be either absolute or relative. */
 int descendant_depth(const Path &path, const Path &parent);
 
 } // namespace FS