LibELF+LibCoreDump: Add a Metadata notes entry

This is a new NotesEntry type which will allow applications to embed
arbitrary metadata in crashdumps (stored as a JSON string). It will be
used to store an assertion message, for example.
This commit is contained in:
Linus Groh 2020-12-30 15:06:33 +01:00 committed by Andreas Kling
parent aa941a31ed
commit 7413a7c509
Notes: sideshowbarker 2024-07-19 00:22:22 +09:00
3 changed files with 42 additions and 2 deletions

View file

@ -24,6 +24,8 @@
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <AK/JsonObject.h>
#include <AK/JsonValue.h>
#include <LibCoreDump/Backtrace.h>
#include <LibCoreDump/Reader.h>
#include <string.h>
@ -69,6 +71,7 @@ ELF::Core::NotesEntryHeader::Type Reader::NotesEntryIterator::type() const
ASSERT(m_current->header.type == ELF::Core::NotesEntryHeader::Type::ProcessInfo
|| m_current->header.type == ELF::Core::NotesEntryHeader::Type::MemoryRegionInfo
|| m_current->header.type == ELF::Core::NotesEntryHeader::Type::ThreadInfo
|| m_current->header.type == ELF::Core::NotesEntryHeader::Type::Metadata
|| m_current->header.type == ELF::Core::NotesEntryHeader::Type::Null);
return m_current->header.type;
}
@ -97,6 +100,11 @@ void Reader::NotesEntryIterator::next()
m_current = reinterpret_cast<const ELF::Core::NotesEntry*>(current->region_name + strlen(current->region_name) + 1);
break;
}
case ELF::Core::NotesEntryHeader::Type::Metadata: {
const auto* current = reinterpret_cast<const ELF::Core::Metadata*>(m_current);
m_current = reinterpret_cast<const ELF::Core::NotesEntry*>(current->json_data + strlen(current->json_data) + 1);
break;
}
default:
ASSERT_NOT_REACHED();
}
@ -141,9 +149,32 @@ const ELF::Core::MemoryRegionInfo* Reader::region_containing(FlatPtr address) co
return ret;
}
Backtrace Reader::backtrace() const
const Backtrace Reader::backtrace() const
{
return Backtrace(*this);
}
const HashMap<String, String> Reader::metadata() const
{
const ELF::Core::Metadata* metadata_notes_entry = nullptr;
for (NotesEntryIterator it((const u8*)m_coredump_image.program_header(m_notes_segment_index).raw_data()); !it.at_end(); it.next()) {
if (it.type() != ELF::Core::NotesEntryHeader::Type::Metadata)
continue;
metadata_notes_entry = reinterpret_cast<const ELF::Core::Metadata*>(it.current());
break;
}
if (!metadata_notes_entry)
return {};
auto metadata_json_value = JsonValue::from_string(metadata_notes_entry->json_data);
if (!metadata_json_value.has_value())
return {};
if (!metadata_json_value.value().is_object())
return {};
HashMap<String, String> metadata;
metadata_json_value.value().as_object().for_each_member([&](auto& key, auto& value) {
metadata.set(key, value.as_string_or({}));
});
return metadata;
}
}

View file

@ -26,6 +26,7 @@
#pragma once
#include <AK/HashMap.h>
#include <AK/MappedFile.h>
#include <AK/Noncopyable.h>
#include <AK/OwnPtr.h>
@ -57,7 +58,8 @@ public:
Optional<uint32_t> peek_memory(FlatPtr address) const;
const ELF::Core::MemoryRegionInfo* region_containing(FlatPtr address) const;
Backtrace backtrace() const;
const Backtrace backtrace() const;
const HashMap<String, String> metadata() const;
private:
class NotesEntryIterator {

View file

@ -39,6 +39,7 @@ struct [[gnu::packed]] NotesEntryHeader
ProcessInfo,
ThreadInfo,
MemoryRegionInfo,
Metadata,
};
Type type;
};
@ -82,4 +83,10 @@ struct [[gnu::packed]] MemoryRegionInfo
}
};
struct [[gnu::packed]] Metadata
{
NotesEntryHeader header;
char json_data[]; // Null terminated
};
}