ENH: Add untaring support

Source/cmSystemTools.cxx

@@ -1382,7 +1382,7 @@ bool cmSystemTools::CreateTar(const char* outFileName, const std::vector<cmStdSt
       TAR_VERBOSE
       | 0) == -1)
     {
-    fprintf(stderr, "tar_open(): %s\n", strerror(errno));
+    cmSystemTools::Error("Problem with tar_open(): ", strerror(errno));
     return false;
     }
 
@@ -1395,9 +1395,10 @@ bool cmSystemTools::CreateTar(const char* outFileName, const std::vector<cmStdSt
     buf[sizeof(buf)-1] = 0;
     if (tar_append_tree(t, buf, pathname) != 0)
       {
-      fprintf(stderr,
-        "tar_append_tree(\"%s\", \"%s\"): %s\n", buf,
-        pathname, strerror(errno));
+      cmOStringStream ostr;
+      ostr << "Problem with tar_append_tree(\"" << buf << "\", \"" << pathname << "\"): "
+        << strerror(errno);
+      cmSystemTools::Error(ostr.str().c_str());
       tar_close(t);
       return false;
       }
@@ -1405,14 +1406,53 @@ bool cmSystemTools::CreateTar(const char* outFileName, const std::vector<cmStdSt
 
   if (tar_append_eof(t) != 0)
     {
-    fprintf(stderr, "tar_append_eof(): %s\n", strerror(errno));
+    cmSystemTools::Error("Problem with tar_append_eof(): ", strerror(errno));
     tar_close(t);
     return false;
     }
 
   if (tar_close(t) != 0)
     {
-    fprintf(stderr, "tar_close(): %s\n", strerror(errno));
+    cmSystemTools::Error("Problem with tar_close(): ", strerror(errno));
+    return false;
+    }
+  return true;
+#else
+  return false;
+#endif
+}
+
+bool cmSystemTools::ExtractTar(const char* outFileName, const std::vector<cmStdString>& files)
+{
+#if defined(CMAKE_BUILD_WITH_CMAKE)
+  TAR *t;
+  // Ok, this libtar is not const safe. for now use auto_ptr hack
+  char* realName = new char[ strlen(outFileName) + 1 ];
+  std::auto_ptr<char> realNamePtr(realName);
+  strcpy(realName, outFileName);
+  if (tar_open(&t, realName,
+      NULL,
+      O_RDONLY
+#ifdef _WIN32
+      | O_BINARY
+#endif
+      , 0,
+      TAR_VERBOSE
+      | 0) == -1)
+    {
+    cmSystemTools::Error("Problem with tar_open(): ", strerror(errno));
+    return false;
+    }
+
+  if (tar_extract_all(t, 0) != 0)
+  {
+    cmSystemTools::Error("Problem with tar_extract_all(): ", strerror(errno));
+    return false;
+  }
+
+  if (tar_close(t) != 0)
+    {
+    cmSystemTools::Error("Problem with tar_close(): ", strerror(errno));
     return false;
     }
   return true;

Source/cmSystemTools.h

@@ -299,6 +299,7 @@ public:
 
   /** Create tar */
   static bool CreateTar(const char* outFileName, const std::vector<cmStdString>& files);
+  static bool ExtractTar(const char* inFileName, const std::vector<cmStdString>& files);
 private:
   static bool s_ForceUnixPaths;
   static bool s_RunCommandHideConsole;

Source/cmake.cxx

@@ -963,6 +963,23 @@ int cmake::CMakeCommand(std::vector<std::string>& args)
       return 0;
       }
 
+    // Untar files
+    else if (args[1] == "untar" && args.size() > 3)
+      {
+      std::string outFile = args[2];
+      std::vector<cmStdString> files;
+      for (std::string::size_type cc = 3; cc < args.size(); cc ++)
+        {
+        files.push_back(args[cc]);
+        }
+      if ( !cmSystemTools::ExtractTar(outFile.c_str(), files) )
+        {
+        cmSystemTools::Error("Problem extracting tar: ", outFile.c_str());
+        return 1;
+        }
+      return 0;
+      }
+
 #if defined(CMAKE_BUILD_WITH_CMAKE)
     // Internal CMake Fortran module support.
     else if (args[1] == "cmake_copy_f90_mod" && args.size() >= 4)