Add rename function

[libs/core.git] / source / utils.cpp

diff --git a/source/utils.cpp b/source/utils.cpp
index 0ca1d6064e1bd2cfcfa48bd8a3b649efc7333ca0..8f06757bda2227f69aa075acc045f1046dba1ce6 100644 (file)
--- a/source/utils.cpp
+++ b/source/utils.cpp
@@ -6,6 +6,7 @@ Distributed under the LGPL
 */
 
 #include <cerrno>
+#include <cstdio>
 #include <msp/core/except.h>
 #ifndef WIN32
 #include <fnmatch.h>
@@ -15,6 +16,7 @@ Distributed under the LGPL
 #include <msp/strings/utils.h>
 #include "dir.h"
 #include "path.h"
+#include "stat.h"
 #include "utils.h"
 
 using namespace std;
@@ -29,6 +31,12 @@ string basename(const Path &p)
 
 Path dirname(const Path &p)
 {
+       if(p.size()==1)
+       {
+               if(p.is_absolute())
+                       return p;
+               return ".";
+       }
        return p.subpath(0, p.size()-1);
 }
 
@@ -40,7 +48,7 @@ string basepart(const string &fn)
 
 string extpart(const string &fn)
 {
-       unsigned dot=fn.rfind('.');
+       string::size_type dot=fn.rfind('.');
        if(dot==string::npos)
                return string();
        return fn.substr(dot);
@@ -78,6 +86,64 @@ Path fix_case(const Path &path)
        return result;
 }
 
+Path readlink(const Path &link)
+{
+#ifdef WIN32
+       (void)link;
+       throw Exception("No symbolic links on win32");
+#else
+       char buf[4096];
+       int len=::readlink(link.str().c_str(), buf, sizeof(buf));
+       if(len==-1)
+               throw SystemError("readlink failed", errno);
+       return string(buf, len);
+#endif
+}
+
+Path realpath(const Path &path)
+{
+#ifdef WIN32
+       if(path.is_absolute())
+               return path;
+       else
+               return getcwd()/path;
+#else
+       list<string> queue(path.begin(), path.end());
+       if(!path.is_absolute())
+       {
+               Path cwd=getcwd();
+               queue.insert(queue.begin(), cwd.begin(), cwd.end());
+       }
+
+       Path real;
+       unsigned n_links=0;
+       while(!queue.empty())
+       {
+               Path next=real/queue.front();
+               queue.pop_front();
+
+               struct stat st=lstat(next);
+               if(S_ISLNK(st.st_mode))
+               {
+                       if(++n_links>64)
+                               throw Exception("Ludicrous amount of symlinks detected in realpath, giving up");
+                       Path link=readlink(next);
+                       queue.insert(queue.begin(), link.begin(), link.end());
+               }
+               else
+                       real=next;
+       }
+
+       return real;
+#endif
+}
+
+void rename(const Path &from, const Path &to)
+{
+       if(::rename(from.str().c_str(), to.str().c_str())==-1)
+               throw SystemError("rename failed", errno);
+}
+
 void unlink(const Path &path)
 {
        if(::unlink(path.str().c_str())==-1)