1 files changed, 27 insertions, 1 deletions
diff --git a/src/common/mac/macho_walker.cc b/src/common/mac/macho_walker.cc
index 3e8fe211..00fde03e 100644
--- a/src/common/mac/macho_walker.cc
+++ b/src/common/mac/macho_walker.cc
@@ -52,6 +52,8 @@ namespace MacFileUtilities {
 MachoWalker::MachoWalker(const char *path, LoadCommandCallback callback,
                          void *context)
     : file_(0),
+      memory_(NULL),
+      memory_size_(0),
       callback_(callback),
       callback_context_(context),
       current_header_(NULL),
@@ -60,6 +62,18 @@ MachoWalker::MachoWalker(const char *path, LoadCommandCallback callback,
   file_ = open(path, O_RDONLY);
 }
 
+MachoWalker::MachoWalker(void *memory, size_t size,
+                         LoadCommandCallback callback, void *context)
+    : file_(0),
+      memory_(memory),
+      memory_size_(size),
+      callback_(callback),
+      callback_context_(context),
+      current_header_(NULL),
+      current_header_size_(0),
+      current_header_offset_(0) {
+}
+
 MachoWalker::~MachoWalker() {
   if (file_ != -1)
     close(file_);
@@ -90,7 +104,19 @@ bool MachoWalker::WalkHeader(int cpu_type) {
 }
 
 bool MachoWalker::ReadBytes(void *buffer, size_t size, off_t offset) {
-  return pread(file_, buffer, size, offset) == (ssize_t)size;
+  if (memory_) {
+    bool result = true;
+    if (offset + size > memory_size_) {
+      size = memory_size_ - offset;
+      result = false;
+    }
+    if (size < 0)
+      return false;
+    memcpy(buffer, static_cast<char *>(memory_) + offset, size);
+    return result;
+  } else {
+    return pread(file_, buffer, size, offset) == (ssize_t)size;
+  }
 }
 
 bool MachoWalker::CurrentHeader(struct mach_header_64 *header, off_t *offset) {