Make Path behave more consistently by always starting relative paths with a dot

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

diff --git a/source/dir.cpp b/source/dir.cpp
index 212200d04918a368b11a0f64050c3ee49cef938e..29c24c188fa96b7d76763b9b1ab5ad4a8aa3de53 100644 (file)
--- a/source/dir.cpp
+++ b/source/dir.cpp
@@ -14,6 +14,7 @@ Distributed under the LGPL
 #endif
 #include <msp/core/except.h>
 #include <msp/strings/regex.h>
+#include <msp/strings/utils.h>
 #include "dir.h"
 #include "path.h"
 #include "stat.h"
@@ -24,6 +25,44 @@ using namespace std;
 namespace Msp {
 namespace FS {
 
+namespace
+{
+
+/**
+Helper function to determine the location of the program's executable.  Caches
+the last result to cut down filesystem access with repeated calls.
+*/
+const Path &get_bin_dir(const string &argv0)
+{
+       static string last_argv0;
+       static Path bin_dir;
+
+       if(!(argv0==last_argv0))
+       {
+               Path exe;
+               if(argv0.find('/')==string::npos)
+               {
+                       const char *path=getenv("PATH");
+                       vector<string> dirs=split(path, ':');
+                       for(vector<string>::const_iterator i=dirs.begin(); i!=dirs.end(); ++i)
+                               if(exists(Path(*i)/argv0))
+                               {
+                                       exe=realpath(Path(*i)/argv0);
+                                       break;
+                               }
+               }
+               else
+                       exe=realpath(argv0);
+
+               last_argv0=argv0;
+               bin_dir=dirname(exe);
+       }
+
+       return bin_dir;
+}
+
+}
+
 void mkdir(const Path &path, int mode)
 {
        int err;
@@ -145,6 +184,31 @@ Path get_user_data_dir(const string &appname)
 #endif
 }
 
+Path get_sys_conf_dir(const string &argv0)
+{
+       Path dir=get_bin_dir(argv0);
+
+       if(dir[-1]=="bin" || dir[-1]=="sbin")
+       {
+               dir/="..";
+               if(dir[-1]=="usr")
+                       dir/="..";
+               return dir/"etc";
+       }
+       else
+               return dir;
+}
+
+Path get_sys_data_dir(const string &argv0, const string &appname)
+{
+       Path dir=get_bin_dir(argv0);
+
+       if(dir[-1]=="bin" || dir[-1]=="sbin")
+               return dir/".."/"share"/appname;
+       else
+               return dir;
+}
+
 void chdir(const Path &path)
 {
        if(::chdir(path.str().c_str())==-1)