Add TemporaryFile class
Added support for creating temporary file
- Constructor creates the temporary file.
- Destructor deletes the file.
- Provided remove function to delete the file.
Signed-off-by: Jayanth Othayoth <ojayanth@in.ibm.com>
Change-Id: I2a5e81af8cf4f4621e5ec6437b936126b7e9ba5a
diff --git a/temporary_file.cpp b/temporary_file.cpp
new file mode 100644
index 0000000..34a18ca
--- /dev/null
+++ b/temporary_file.cpp
@@ -0,0 +1,64 @@
+#include "temporary_file.hpp"
+
+#include <fmt/format.h>
+#include <unistd.h>
+
+#include <phosphor-logging/elog-errors.hpp>
+
+#include <cerrno>
+#include <cstdlib>
+#include <stdexcept>
+#include <string>
+
+namespace openpower::util
+{
+using namespace phosphor::logging;
+
+TemporaryFile::TemporaryFile()
+{
+ // Build template path required by mkstemp()
+ std::string templatePath =
+ fs::temp_directory_path() / "openpower-proc-control-XXXXXX";
+
+ // Generate unique file name, create file, and open it. The XXXXXX
+ // characters are replaced by mkstemp() to make the file name unique.
+ int fd = mkstemp(templatePath.data());
+ if (fd == -1)
+ {
+ throw std::runtime_error{
+ std::string{"Unable to create temporary file: "} + strerror(errno)};
+ }
+
+ // Store path to temporary file
+ path = templatePath;
+
+ // Close file descriptor
+ if (close(fd) == -1)
+ {
+ // Save errno value; will likely change when we delete temporary file
+ int savedErrno = errno;
+
+ // Delete temporary file. The destructor won't be called because
+ // the exception below causes this constructor to exit without
+ // completing.
+ remove();
+
+ throw std::runtime_error{
+ std::string{"Unable to close temporary file: "} +
+ strerror(savedErrno)};
+ }
+}
+
+void TemporaryFile::remove()
+{
+ if (!path.empty())
+ {
+ // Delete temporary file from file system
+ fs::remove(path);
+
+ // Clear path to indicate file has been deleted
+ path.clear();
+ }
+}
+
+} // namespace openpower::util