Add support for packed relocations.
Change-Id: I796a4ce86d3fccb8361c19889419c96147ee3c9f
diff --git a/linker/linker_reloc_iterators.h b/linker/linker_reloc_iterators.h
index 6388bb0..5db31f9 100644
--- a/linker/linker_reloc_iterators.h
+++ b/linker/linker_reloc_iterators.h
@@ -19,6 +19,18 @@
#include "linker.h"
+#include <string.h>
+
+#define RELOCATION_GROUPED_BY_INFO_FLAG 1
+#define RELOCATION_GROUPED_BY_OFFSET_DELTA_FLAG 2
+#define RELOCATION_GROUPED_BY_ADDEND_FLAG 4
+#define RELOCATION_GROUP_HAS_ADDEND_FLAG 8
+
+#define RELOCATION_GROUPED_BY_INFO(flags) (((flags) & RELOCATION_GROUPED_BY_INFO_FLAG) != 0)
+#define RELOCATION_GROUPED_BY_OFFSET_DELTA(flags) (((flags) & RELOCATION_GROUPED_BY_OFFSET_DELTA_FLAG) != 0)
+#define RELOCATION_GROUPED_BY_ADDEND(flags) (((flags) & RELOCATION_GROUPED_BY_ADDEND_FLAG) != 0)
+#define RELOCATION_GROUP_HAS_ADDEND(flags) (((flags) & RELOCATION_GROUP_HAS_ADDEND_FLAG) != 0)
+
class plain_reloc_iterator {
#if defined(USE_RELA)
typedef ElfW(Rela) rel_t;
@@ -44,4 +56,97 @@
DISALLOW_COPY_AND_ASSIGN(plain_reloc_iterator);
};
+template <typename decoder_t>
+class packed_reloc_iterator {
+#if defined(USE_RELA)
+ typedef ElfW(Rela) rel_t;
+#else
+ typedef ElfW(Rel) rel_t;
+#endif
+ public:
+ explicit packed_reloc_iterator(decoder_t&& decoder)
+ : decoder_(decoder) {
+ // initialize fields
+ memset(&reloc_, 0, sizeof(reloc_));
+ relocation_count_ = decoder_.pop_front();
+ reloc_.r_offset = decoder_.pop_front();
+ relocation_index_ = 0;
+ relocation_group_index_ = 0;
+ group_size_ = 0;
+ }
+
+ bool has_next() const {
+ return relocation_index_ < relocation_count_;
+ }
+
+ rel_t* next() {
+ if (relocation_group_index_ == group_size_) {
+ if (!read_group_fields()) {
+ // Iterator is inconsistent state; it should not be called again
+ // but in case it is let's make sure has_next() returns false.
+ relocation_index_ = relocation_count_ = 0;
+ return nullptr;
+ }
+ }
+
+ if (RELOCATION_GROUPED_BY_OFFSET_DELTA(group_flags_)) {
+ reloc_.r_offset += group_r_offset_delta_;
+ } else {
+ reloc_.r_offset += decoder_.pop_front();
+ }
+
+ if (!RELOCATION_GROUPED_BY_INFO(group_flags_)) {
+ reloc_.r_info = decoder_.pop_front();
+ }
+
+#if defined(USE_RELA)
+ if (RELOCATION_GROUP_HAS_ADDEND(group_flags_) && !RELOCATION_GROUPED_BY_ADDEND(group_flags_)) {
+ reloc_.r_addend += decoder_.pop_front();
+ }
+#endif
+
+ relocation_index_++;
+ relocation_group_index_++;
+
+ return &reloc_;
+ }
+ private:
+ bool read_group_fields() {
+ group_size_ = decoder_.pop_front();
+ group_flags_ = decoder_.pop_front();
+
+ if (RELOCATION_GROUPED_BY_OFFSET_DELTA(group_flags_)) {
+ group_r_offset_delta_ = decoder_.pop_front();
+ }
+
+ if (RELOCATION_GROUPED_BY_INFO(group_flags_)) {
+ reloc_.r_info = decoder_.pop_front();
+ }
+
+ if (RELOCATION_GROUP_HAS_ADDEND(group_flags_) && RELOCATION_GROUPED_BY_ADDEND(group_flags_)) {
+#if !defined(USE_RELA)
+ // This platform does not support rela, and yet we have it encoded in android_rel section.
+ DL_ERR("unexpected r_addend in android.rel section");
+ return false;
+#else
+ reloc_.r_addend += decoder_.pop_front();
+ } else if (!RELOCATION_GROUP_HAS_ADDEND(group_flags_)) {
+ reloc_.r_addend = 0;
+#endif
+ }
+
+ relocation_group_index_ = 0;
+ return true;
+ }
+
+ decoder_t decoder_;
+ size_t relocation_count_;
+ size_t group_size_;
+ size_t group_flags_;
+ size_t group_r_offset_delta_;
+ size_t relocation_index_;
+ size_t relocation_group_index_;
+ rel_t reloc_;
+};
+
#endif // __LINKER_RELOC_ITERATORS_H