Merge pull request #5238 from diffblue/file_rename

File rename

Author: Daniel Kroening

src/goto-cc/as_mode.cpp

@@ -24,6 +24,7 @@ Author: Michael Tautschnig
 #include <cstring>
 
 #include <util/config.h>
+#include <util/file_util.h>
 #include <util/get_base_name.h>
 #include <util/run.h>
 #include <util/tempdir.h>
@@ -289,14 +290,17 @@ int as_modet::as_hybrid_binary(const compilet &compiler)
 
   // save the goto-cc output file
   std::string saved = output_file + ".goto-cc-saved";
-  int result = rename(output_file.c_str(), saved.c_str());
-  if(result!=0)
+  try
   {
-    error() << "Rename failed: " << std::strerror(errno) << eom;
-    return result;
+    file_rename(output_file, saved);
+  }
+  catch(const cprover_exception_baset &e)
+  {
+    error() << "Rename failed: " << e.what() << eom;
+    return 1;
   }
 
-  result=run_as();
+  int result = run_as();
 
   if(result == 0)
   {

src/goto-cc/gcc_mode.cpp

@@ -937,12 +937,17 @@ int gcc_modet::gcc_hybrid_binary(compilet &compiler)
       it++)
   {
     std::string bin_name=*it+goto_binary_tmp_suffix;
-    int result=rename(it->c_str(), bin_name.c_str());
-    if(result!=0)
+
+    try
     {
-      error() << "Rename failed: " << std::strerror(errno) << eom;
-      return result;
+      file_rename(*it, bin_name);
     }
+    catch(const cprover_exception_baset &e)
+    {
+      error() << "Rename failed: " << e.what() << eom;
+      return 1;
+    }
+
     goto_binaries.push_back(bin_name);
   }
 

src/goto-cc/ld_mode.cpp

@@ -189,16 +189,17 @@ int ld_modet::ld_hybrid_binary(compilet &compiler)
   // save the goto-cc output file
   std::string goto_binary = output_file + goto_binary_tmp_suffix;
 
-  int result;
-
-  result = rename(output_file.c_str(), goto_binary.c_str());
-  if(result != 0)
+  try
+  {
+    file_rename(output_file, goto_binary);
+  }
+  catch(const cprover_exception_baset &e)
   {
-    error() << "Rename failed: " << std::strerror(errno) << eom;
-    return result;
+    error() << "Rename failed: " << e.what() << eom;
+    return 1;
   }
 
-  result = run_ld();
+  int result = run_ld();
 
   if(result == 0 && cmdline.isset('T'))
   {

src/util/file_util.cpp

@@ -221,3 +221,41 @@ bool file_remove(const std::string &path)
   return unlink(path.c_str()) == 0;
 #endif
 }
+
+void file_rename(const std::string &old_path, const std::string &new_path)
+{
+#ifdef _WIN32
+  if(is_directory(old_path))
+  {
+    // rename() only renames directories, but does not move them.
+    // MoveFile is not atomic.
+    auto MoveFile_result =
+      MoveFileW(widen(old_path).c_str(), widen(new_path).c_str());
+
+    if(MoveFile_result == 0)
+      throw system_exceptiont("MoveFile failed");
+  }
+  else
+  {
+    // C++17 requires this to be atomic, which is delivered by
+    // ReplaceFile(). MoveFile() or rename() do not guarantee this.
+    // Any existing file at new_path is to be overwritten.
+    auto ReplaceFile_result = ReplaceFileW(
+      widen(new_path).c_str(), // note the ordering
+      widen(old_path).c_str(),
+      nullptr,  // lpBackupFileName
+      0,        // dwReplaceFlags
+      nullptr,  // lpExclude
+      nullptr); // lpReserved
+
+    if(ReplaceFile_result == 0)
+      throw system_exceptiont("ReplaceFile failed");
+  }
+#else
+  int rename_result = rename(old_path.c_str(), new_path.c_str());
+
+  if(rename_result != 0)
+    throw system_exceptiont(
+      std::string("rename failed: ") + std::strerror(errno));
+#endif
+}

src/util/file_util.h

@@ -42,4 +42,9 @@ bool file_exists(const std::string &path);
 /// \return true if the file was deleted, false if it did not exist
 bool file_remove(const std::string &path);
 
+/// Rename a file.
+/// C++17 will allow us to use std::filesystem::rename
+/// Throws an exception on failure.
+void file_rename(const std::string &old_path, const std::string &new_path);
+
 #endif // CPROVER_UTIL_FILE_UTIL_H