Print ELF header/segments/sections

[centaur.git] / src / lookup / last-section-in-segment.c

diff --git a/src/lookup/last-section-in-segment.c b/src/lookup/last-section-in-segment.c
new file mode 100644 (file)
index 0000000..0e78263
--- /dev/null
+++ b/src/lookup/last-section-in-segment.c
@@ -0,0 +1,49 @@
+#include <libelf.h>
+#include <gelf.h>
+
+#include <libelfu/libelfu.h>
+
+
+/*
+ * Returns the first section that  is contained in the segment and
+ * ends as close to its memory image of as possible (the "last"
+ * section in the segment).
+ *
+ * If no section fits, NULL is returned.
+ */
+Elf_Scn* elfu_lastSectionInSegment(Elf *e, GElf_Phdr *phdr)
+{
+  Elf_Scn *last = NULL;
+  Elf_Scn *scn;
+
+
+  scn = elf_getscn(e, 1);
+  while (scn) {
+    if (elfu_segmentContainsSection(phdr, scn) == ELFU_TRUE) {
+      if (!last) {
+        last = scn;
+      } else {
+        GElf_Shdr shdrOld;
+        GElf_Shdr shdrNew;
+
+        if (gelf_getshdr(last, &shdrOld) != &shdrOld) {
+          continue;
+        }
+
+        if (gelf_getshdr(scn, &shdrNew) != &shdrNew) {
+          continue;
+        }
+
+        if (shdrNew.sh_offset + shdrNew.sh_size
+            > shdrOld.sh_offset + shdrOld.sh_size) {
+          // TODO: Check (leftover space in memory image) < (p_align)
+          last = scn;
+        }
+      }
+    }
+
+    scn = elf_nextscn(e, scn);
+  }
+
+  return last;
+}