libdebug: Improve handling of stripped binaries.

- When searching for the symbol table, first see if the normal SHT_SYMTAB
  section is present. If not, fall back to trying to use SHT_DYNSYM if
  present. This allows us to resolve non-static functions/symbols
  in stripped binaries for the purposes of crash reports/disassembly.

src/kits/debug/Image.cpp

@@ -305,9 +305,6 @@ ImageFile::_LoadFile(const char* path, addr_t* _textAddress, size_t* _textSize,
 		return B_NOT_AN_EXECUTABLE;
 	}
 
-	elf_shdr* sectionHeaders
-		= (elf_shdr*)(fMappedFile + elfHeader->e_shoff);
-
 	// find the text and data segment -- we need load address and size
 	*_textAddress = 0;
 	*_textSize = 0;
@@ -328,12 +325,26 @@ ImageFile::_LoadFile(const char* path, addr_t* _textAddress, size_t* _textSize,
 		}
 	}
 
+	status_t error = _FindTableInSection(elfHeader, SHT_SYMTAB);
+	if (error != B_OK)
+		error = _FindTableInSection(elfHeader, SHT_DYNSYM);
+
+	return error;
+}
+
+
+status_t
+ImageFile::_FindTableInSection(elf_ehdr* elfHeader, uint16 sectionType)
+{
+	elf_shdr* sectionHeaders
+		= (elf_shdr*)(fMappedFile + elfHeader->e_shoff);
+
 	// find the symbol table
 	for (int32 i = 0; i < elfHeader->e_shnum; i++) {
 		elf_shdr* sectionHeader = (elf_shdr*)
 			((uint8*)sectionHeaders + i * elfHeader->e_shentsize);
 
-		if (sectionHeader->sh_type == SHT_SYMTAB) {
+		if (sectionHeader->sh_type == sectionType) {
 			elf_shdr& stringHeader = *(elf_shdr*)
 				((uint8*)sectionHeaders
 					+ sectionHeader->sh_link * elfHeader->e_shentsize);

src/kits/debug/Image.h

@@ -96,6 +96,9 @@ private:
 									addr_t* _textAddress, size_t* _textSize,
 									addr_t* _dataAddress, size_t* _dataSize);
 
+			status_t			_FindTableInSection(elf_ehdr* elfHeader,
+									uint16 sectionType);
+
 private:
 			int					fFD;
 			off_t				fFileSize;