From a827925ebe5643ef03ca50dc307b1542f58c5378 Mon Sep 17 00:00:00 2001
From: Mike Hommey <mh+mozilla@glandium.org>
Date: Wed, 3 Aug 2011 10:28:47 +0200
Subject: [PATCH] Bug 674888 - Allow elfhack to move .interp sections. r=tglek

---
 build/unix/elfhack/elf.cpp |  5 ++++-
 build/unix/elfhack/elfxx.h | 26 +++++++++++++++++++++++++-
 2 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/build/unix/elfhack/elf.cpp b/build/unix/elfhack/elf.cpp
index 31a30a8e6b5d..071891fe55ad 100644
--- a/build/unix/elfhack/elf.cpp
+++ b/build/unix/elfhack/elf.cpp
@@ -566,6 +566,7 @@ void ElfSegment::addSection(ElfSection *section)
         if ((*i)->getAddr() > section->getAddr())
             break;
     sections.insert(i, section);
+    section->addToSegment(this);
 }
 
 unsigned int ElfSegment::getFileSize()
@@ -636,8 +637,10 @@ ElfSegment *ElfSegment::splitBefore(ElfSection *section)
     phdr.p_memsz = (unsigned int)-1;
     ElfSegment *segment = new ElfSegment(&phdr);
 
-    for (rm = i; i != sections.end(); ++i)
+    for (rm = i; i != sections.end(); ++i) {
+        (*i)->removeFromSegment(this);
         segment->addSection(*i);
+    }
     sections.erase(rm, sections.end());
 
     return segment;
diff --git a/build/unix/elfhack/elfxx.h b/build/unix/elfhack/elfxx.h
index d06271c12bd7..4ecb1fb8eb39 100644
--- a/build/unix/elfhack/elfxx.h
+++ b/build/unix/elfhack/elfxx.h
@@ -41,6 +41,7 @@
 #include <cstring>
 #include <iostream>
 #include <fstream>
+#include <algorithm>
 #include <elf.h>
 #include <asm/byteorder.h>
 
@@ -370,7 +371,8 @@ public:
                 (getType() == SHT_GNU_HASH) ||
                 (getType() == SHT_GNU_verdef) ||
                 (getType() == SHT_GNU_verneed) ||
-                (getType() == SHT_GNU_versym)) &&
+                (getType() == SHT_GNU_versym) ||
+                isInSegmentType(PT_INTERP)) &&
                 (getFlags() & SHF_ALLOC);
     }
 
@@ -410,6 +412,20 @@ public:
         file.seekp(getOffset());
         file.write(data, getSize());
     }
+
+private:
+    friend class ElfSegment;
+
+    void addToSegment(ElfSegment *segment) {
+        segments.push_back(segment);
+    }
+
+    void removeFromSegment(ElfSegment *segment) {
+        std::vector<ElfSegment *>::iterator i = std::find(segments.begin(), segments.end(), segment);
+        segments.erase(i, i + 1);
+    }
+
+    bool isInSegmentType(unsigned int type);
 protected:
     Elf_Shdr shdr;
     char *data;
@@ -419,6 +435,7 @@ private:
     SectionInfo info;
     ElfSection *next, *previous;
     int index;
+    std::vector<ElfSegment *> segments;
 };
 
 class ElfSegment {
@@ -636,6 +653,13 @@ inline unsigned int Elf::getSize() {
     return section->getOffset() + section->getSize();
 }
 
+inline bool ElfSection::isInSegmentType(unsigned int type) {
+    for (std::vector<ElfSegment *>::iterator seg = segments.begin(); seg != segments.end(); seg++)
+        if ((*seg)->getType() == type)
+            return true;
+    return false;
+}
+
 inline ElfLocation::ElfLocation(ElfSection *section, unsigned int off, enum position pos)
 : section(section) {
     if ((pos == ABSOLUTE) && section)