[Lldb-commits] [lldb] [llvm] [LLDB][Minidump] Add 64b support to LLDB's minidump file builder. (PR #95312)

[Greg Clayton via lldb-commits]

================
@@ -81,38 +82,42 @@ Status MinidumpFileBuilder::AddHeaderAndCalculateDirectories() {
   // Now offset the file by the directores so we can write them in later.
   offset_t directory_offset = m_expected_directories * directory_size;
   m_saved_data_size += directory_offset;
-  // Replace this when we make a better way to do this.
   Status error;
-  Header empty_header;
-  size_t bytes_written;
-  bytes_written = header_size;
-  error = m_core_file->Write(&empty_header, bytes_written);
-  if (error.Fail() || bytes_written != header_size) {
-    if (bytes_written != header_size)
+  size_t zeroes = 0; // 8 0's
+  size_t remaining_bytes = m_saved_data_size;
+  while (remaining_bytes > 0) {
+    // Keep filling in zero's until we preallocate enough space for the header
+    // and directory sections.
+    size_t bytes_written = std::min(remaining_bytes, sizeof(size_t));
+    error = m_core_file->Write(&zeroes, bytes_written);
+    if (error.Fail()) {
       error.SetErrorStringWithFormat(
-          "unable to write the header (written %zd/%zd)", bytes_written,
-          header_size);
-    return error;
-  }
-
-  for (uint i = 0; i < m_expected_directories; i++) {
-    size_t bytes_written;
-    bytes_written = directory_size;
-    Directory empty_directory;
-    error = m_core_file->Write(&empty_directory, bytes_written);
-    if (error.Fail() || bytes_written != directory_size) {
-      if (bytes_written != directory_size)
-        error.SetErrorStringWithFormat(
-            "unable to write the directory (written %zd/%zd)", bytes_written,
-            directory_size);
-      return error;
+        "Unable to write header and directory padding (written %zd/%zd)",
+        remaining_bytes - m_saved_data_size, m_saved_data_size);
+      break;
     }
+
+    remaining_bytes -= bytes_written;
   }
----------------
clayborg wrote:

Remove this while look and complex functionality and just call:
```
m_core_file->SeekFromStart(m_saved_data_size);
```
No need to write zeroes.

https://github.com/llvm/llvm-project/pull/95312