LibCoreDump: Add library for parsing coredump files

4 files changed, 226 insertions, 0 deletions

diff --git a/Libraries/CMakeLists.txt b/Libraries/CMakeLists.txt
index 1d205d3cc3..46f6513bd9 100644
--- a/Libraries/CMakeLists.txt
+++ b/Libraries/CMakeLists.txt
@@ -3,6 +3,7 @@ add_subdirectory(LibC)
 add_subdirectory(LibChess)
 add_subdirectory(LibCompress)
 add_subdirectory(LibCore)
+add_subdirectory(LibCoreDump)
 add_subdirectory(LibCpp)
 add_subdirectory(LibCrypt)
 add_subdirectory(LibCrypto)
diff --git a/Libraries/LibCoreDump/CMakeLists.txt b/Libraries/LibCoreDump/CMakeLists.txt
new file mode 100644
index 0000000000..dd85d22d36
--- /dev/null
+++ b/Libraries/LibCoreDump/CMakeLists.txt
@@ -0,0 +1,6 @@
+set(SOURCES
+    CoreDumpReader.cpp
+)
+
+serenity_lib(LibCoreDump coredump)
+target_link_libraries(LibCoreDump LibC LibCore)
diff --git a/Libraries/LibCoreDump/CoreDumpReader.cpp b/Libraries/LibCoreDump/CoreDumpReader.cpp
new file mode 100644
index 0000000000..d4890698fe
--- /dev/null
+++ b/Libraries/LibCoreDump/CoreDumpReader.cpp
@@ -0,0 +1,119 @@
+/*
+ * Copyright (c) 2020, Itamar S. <itamar8910@gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "CoreDumpReader.h"
+#include <string.h>
+
+OwnPtr<CoreDumpReader> CoreDumpReader::create(const String& path)
+{
+    auto mapped_file = make<MappedFile>(path);
+    if (!mapped_file->is_valid())
+        return nullptr;
+    return make<CoreDumpReader>(move(mapped_file));
+}
+
+CoreDumpReader::CoreDumpReader(OwnPtr<MappedFile>&& coredump_file)
+    : m_coredump_file(move(coredump_file))
+    , m_coredump_image((u8*)m_coredump_file->data(), m_coredump_file->size())
+{
+    size_t index = 0;
+    m_coredump_image.for_each_program_header([this, &index](auto pheader) {
+        if (pheader.type() == PT_NOTE) {
+            m_notes_segment_index = index;
+            return IterationDecision::Break;
+        }
+        ++index;
+        return IterationDecision::Continue;
+    });
+    ASSERT(m_notes_segment_index != -1);
+}
+
+CoreDumpReader::~CoreDumpReader()
+{
+}
+
+CoreDumpReader::NotesEntryIterator::NotesEntryIterator(const u8* notes_data)
+    : m_current((const ELF::Core::NotesEntry*)notes_data)
+    , start(notes_data)
+{
+}
+
+ELF::Core::NotesEntryHeader::Type CoreDumpReader::NotesEntryIterator::type() const
+{
+    ASSERT(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::Null);
+    return m_current->header.type;
+}
+
+const ELF::Core::NotesEntry* CoreDumpReader::NotesEntryIterator::current() const
+{
+    return m_current;
+}
+
+void CoreDumpReader::NotesEntryIterator::next()
+{
+    ASSERT(!at_end());
+    if (type() == ELF::Core::NotesEntryHeader::Type::ThreadInfo) {
+        const ELF::Core::ThreadInfo* current = (const ELF::Core::ThreadInfo*)m_current;
+        m_current = (const ELF::Core::NotesEntry*)(current + 1);
+        return;
+    }
+    if (type() == ELF::Core::NotesEntryHeader::Type::MemoryRegionInfo) {
+        const ELF::Core::MemoryRegionInfo* current = (const ELF::Core::MemoryRegionInfo*)m_current;
+        m_current = (const ELF::Core::NotesEntry*)(current->region_name + strlen(current->region_name) + 1);
+        return;
+    }
+}
+
+bool CoreDumpReader::NotesEntryIterator::at_end() const
+{
+    return type() == ELF::Core::NotesEntryHeader::Type::Null;
+}
+
+Optional<uint32_t> CoreDumpReader::peek_memory(FlatPtr address) const
+{
+    const auto* region = region_containing(address);
+    if (!region)
+        return {};
+
+    FlatPtr offset_in_region = address - region->region_start;
+    const char* region_data = image().program_header(region->program_header_index).raw_data();
+    return *(const uint32_t*)(&region_data[offset_in_region]);
+}
+
+const ELF::Core::MemoryRegionInfo* CoreDumpReader::region_containing(FlatPtr address) const
+{
+    const ELF::Core::MemoryRegionInfo* ret = nullptr;
+    for_each_memory_region_info([&ret, address](const ELF::Core::MemoryRegionInfo* region_info) {
+        if (region_info->region_start <= address && region_info->region_end >= address) {
+            ret = region_info;
+            return IterationDecision::Break;
+        }
+        return IterationDecision::Continue;
+    });
+    return ret;
+}
diff --git a/Libraries/LibCoreDump/CoreDumpReader.h b/Libraries/LibCoreDump/CoreDumpReader.h
new file mode 100644
index 0000000000..c898911e4c
--- /dev/null
+++ b/Libraries/LibCoreDump/CoreDumpReader.h
@@ -0,0 +1,100 @@
+/*
+ * Copyright (c) 2020, Itamar S. <itamar8910@gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#pragma once
+
+#include <AK/MappedFile.h>
+#include <AK/Noncopyable.h>
+#include <AK/OwnPtr.h>
+#include <LibELF/CoreDump.h>
+#include <LibELF/Image.h>
+
+class CoreDumpReader {
+    AK_MAKE_NONCOPYABLE(CoreDumpReader);
+
+public:
+    static OwnPtr<CoreDumpReader> create(const String&);
+    ~CoreDumpReader();
+
+    CoreDumpReader(OwnPtr<MappedFile>&&);
+
+    template<typename Func>
+    void for_each_memory_region_info(Func func) const;
+
+    template<typename Func>
+    void for_each_thread_info(Func func) const;
+
+    const ELF::Image& image() const { return m_coredump_image; }
+
+    Optional<uint32_t> peek_memory(FlatPtr address) const;
+    const ELF::Core::MemoryRegionInfo* region_containing(FlatPtr address) const;
+
+private:
+    class NotesEntryIterator {
+    public:
+        NotesEntryIterator(const u8* notes_data);
+
+        ELF::Core::NotesEntryHeader::Type type() const;
+        const ELF::Core::NotesEntry* current() const;
+
+        void next();
+        bool at_end() const;
+
+    private:
+        const ELF::Core::NotesEntry* m_current { nullptr };
+        const u8* start { nullptr };
+    };
+
+    OwnPtr<MappedFile> m_coredump_file;
+    ELF::Image m_coredump_image;
+    ssize_t m_notes_segment_index { -1 };
+};
+
+template<typename Func>
+void CoreDumpReader::for_each_memory_region_info(Func func) const
+{
+    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::MemoryRegionInfo)
+            continue;
+        auto* region = (const ELF::Core::MemoryRegionInfo*)(it.current());
+        IterationDecision decision = func(region);
+        if (decision == IterationDecision::Break)
+            return;
+    }
+}
+
+template<typename Func>
+void CoreDumpReader::for_each_thread_info(Func func) const
+{
+    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::ThreadInfo)
+            continue;
+        auto* region = (const ELF::Core::ThreadInfo*)(it.current());
+        IterationDecision decision = func(region);
+        if (decision == IterationDecision::Break)
+            return;
+    }
+}