issue 243 - Linux dumper should use build id produced by ld --build-id if available

R=thestig at http://breakpad.appspot.com/185001

git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@830 4c0a9323-5329-0410-9bdc-e9ce6186880e

1 files changed, 95 insertions, 55 deletions

diff --git a/src/common/linux/file_id_unittest.cc b/src/common/linux/file_id_unittest.cc
index f5298b12..24208983 100644
--- a/src/common/linux/file_id_unittest.cc
+++ b/src/common/linux/file_id_unittest.cc
@@ -33,18 +33,20 @@
 #include <stdlib.h>
 
 #include "common/linux/file_id.h"
+#include "common/linux/synth_elf.h"
+#include "common/test_assembler.h"
 #include "breakpad_googletest_includes.h"
 
 using namespace google_breakpad;
-
-namespace {
-typedef testing::Test FileIDTest;
-}
-
-TEST(FileIDTest, FileIDStrip) {
-  // Calculate the File ID of our binary using
-  // FileID::ElfFileIdentifier, then make a copy of our binary,
-  // strip it, and ensure that we still get the same result.
+using google_breakpad::synth_elf::BuildIDNote;
+using google_breakpad::synth_elf::ELF;
+using google_breakpad::test_assembler::kLittleEndian;
+using google_breakpad::test_assembler::Section;
+
+TEST(FileIDStripTest, StripSelf) {
+  // Calculate the File ID of this binary using
+  // FileID::ElfFileIdentifier, then make a copy of this binary,
+  // strip it, and ensure that the result is the same.
   char exe_name[PATH_MAX];
   ssize_t len = readlink("/proc/self/exe", exe_name, PATH_MAX - 1);
   ASSERT_NE(len, -1);
@@ -75,58 +77,40 @@ TEST(FileIDTest, FileIDStrip) {
   unlink(templ);
 }
 
-struct ElfClass32 {
-  typedef Elf32_Ehdr Ehdr;
-  typedef Elf32_Shdr Shdr;
-  static const int kClass = ELFCLASS32;
-};
+class FileIDTest : public testing::Test {
+public:
+  void GetElfContents(ELF& elf) {
+    string contents;
+    ASSERT_TRUE(elf.GetContents(&contents));
+    ASSERT_LT(0, contents.size());
 
-struct ElfClass64 {
-  typedef Elf64_Ehdr Ehdr;
-  typedef Elf64_Shdr Shdr;
-  static const int kClass = ELFCLASS64;
-};
-
-template<typename ElfClass>
-struct ElfishElf {
-  static const size_t kTextSectionSize = 128;
-  typedef typename ElfClass::Ehdr Ehdr;
-  typedef typename ElfClass::Shdr Shdr;
-
-  Ehdr elf_header;
-  Shdr text_header;
-  Shdr string_header;
-  char text_section[kTextSectionSize];
-  char string_section[8];
-
-  static void Populate(ElfishElf* elf) {
-    memset(elf, 0, sizeof(ElfishElf));
-    memcpy(elf, ELFMAG, SELFMAG);
-    elf->elf_header.e_ident[EI_CLASS] = ElfClass::kClass;
-    elf->elf_header.e_shoff = offsetof(ElfishElf, text_header);
-    elf->elf_header.e_shnum = 2;
-    elf->elf_header.e_shstrndx = 1;
-    elf->text_header.sh_name = 0;
-    elf->text_header.sh_type = SHT_PROGBITS;
-    elf->text_header.sh_offset = offsetof(ElfishElf, text_section);
-    elf->text_header.sh_size = kTextSectionSize;
-    for (size_t i = 0; i < kTextSectionSize; ++i) {
-      elf->text_section[i] = i * 3;
-    }
-    elf->string_header.sh_offset = offsetof(ElfishElf, string_section);
-    strcpy(elf->string_section, ".text");
+    elfdata_v.clear();
+    elfdata_v.insert(elfdata_v.begin(), contents.begin(), contents.end());
+    elfdata = &elfdata_v[0];
   }
+
+  vector<uint8_t> elfdata_v;
+  uint8_t* elfdata;
 };
 
-TEST(FileIDTest, ElfClass) {
+TEST_F(FileIDTest, ElfClass) {
   uint8_t identifier[sizeof(MDGUID)];
   const char expected_identifier_string[] =
       "80808080-8080-0000-0000-008080808080";
   char identifier_string[sizeof(expected_identifier_string)];
+  const size_t kTextSectionSize = 128;
+
+  ELF elf32(EM_386, ELFCLASS32, kLittleEndian);
+  Section text32(kLittleEndian);
+  for (size_t i = 0; i < kTextSectionSize; ++i) {
+    text32.D8(i * 3);
+  }
+  elf32.AddSection(".text", text32, SHT_PROGBITS);
+  elf32.Finish();
+  GetElfContents(elf32);
+
+  EXPECT_TRUE(FileID::ElfFileIdentifierFromMappedFile(elfdata, identifier));
 
-  ElfishElf<ElfClass32> elf32;
-  ElfishElf<ElfClass32>::Populate(&elf32);
-  EXPECT_TRUE(FileID::ElfFileIdentifierFromMappedFile(&elf32, identifier));
   FileID::ConvertIdentifierToString(identifier, identifier_string,
                                     sizeof(identifier_string));
   EXPECT_STREQ(expected_identifier_string, identifier_string);
@@ -134,9 +118,65 @@ TEST(FileIDTest, ElfClass) {
   memset(identifier, 0, sizeof(identifier));
   memset(identifier_string, 0, sizeof(identifier_string));
 
-  ElfishElf<ElfClass64> elf64;
-  ElfishElf<ElfClass64>::Populate(&elf64);
-  EXPECT_TRUE(FileID::ElfFileIdentifierFromMappedFile(&elf64, identifier));
+  ELF elf64(EM_X86_64, ELFCLASS64, kLittleEndian);
+  Section text64(kLittleEndian);
+  for (size_t i = 0; i < kTextSectionSize; ++i) {
+    text64.D8(i * 3);
+  }
+  elf64.AddSection(".text", text64, SHT_PROGBITS);
+  elf64.Finish();
+  GetElfContents(elf64);
+
+  EXPECT_TRUE(FileID::ElfFileIdentifierFromMappedFile(elfdata, identifier));
+
+  FileID::ConvertIdentifierToString(identifier, identifier_string,
+                                    sizeof(identifier_string));
+  EXPECT_STREQ(expected_identifier_string, identifier_string);
+}
+
+TEST_F(FileIDTest, BuildID) {
+  const uint8_t kExpectedIdentifier[sizeof(MDGUID)] =
+    {0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+     0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F};
+  char expected_identifier_string[] =
+    "00000000-0000-0000-0000-000000000000";
+  FileID::ConvertIdentifierToString(kExpectedIdentifier,
+                                    expected_identifier_string,
+                                    sizeof(expected_identifier_string));
+
+  uint8_t identifier[sizeof(MDGUID)];
+  char identifier_string[sizeof(expected_identifier_string)];
+
+  ELF elf32(EM_386, ELFCLASS32, kLittleEndian);
+  Section text(kLittleEndian);
+  text.Append(4096, 0);
+  elf32.AddSection(".text", text, SHT_PROGBITS);
+  BuildIDNote::AppendSection(elf32,
+                             kExpectedIdentifier,
+                             sizeof(kExpectedIdentifier));
+  elf32.Finish();
+  GetElfContents(elf32);
+
+  EXPECT_TRUE(FileID::ElfFileIdentifierFromMappedFile(elfdata, identifier));
+
+  FileID::ConvertIdentifierToString(identifier, identifier_string,
+                                    sizeof(identifier_string));
+  EXPECT_STREQ(expected_identifier_string, identifier_string);
+
+  memset(identifier, 0, sizeof(identifier));
+  memset(identifier_string, 0, sizeof(identifier_string));
+
+  ELF elf64(EM_X86_64, ELFCLASS64, kLittleEndian);
+  // Re-use empty text section from previous test
+  elf64.AddSection(".text", text, SHT_PROGBITS);
+  BuildIDNote::AppendSection(elf64,
+                             kExpectedIdentifier,
+                             sizeof(kExpectedIdentifier));
+  elf64.Finish();
+  GetElfContents(elf64);
+
+  EXPECT_TRUE(FileID::ElfFileIdentifierFromMappedFile(elfdata, identifier));
+
   FileID::ConvertIdentifierToString(identifier, identifier_string,
                                     sizeof(identifier_string));
   EXPECT_STREQ(expected_identifier_string, identifier_string);