Add a MappedMemory interface to TaskMemory and use it in MachOImageSymbolTableReader

util/mac/mach_o_image_symbol_table_reader.cc

Index: util/mac/mach_o_image_symbol_table_reader.cc
diff --git a/util/mac/mach_o_image_symbol_table_reader.cc b/util/mac/mach_o_image_symbol_table_reader.cc
index 51e1261e71c99910c0287bbba2110430deac796a..0b64fd460cf6a929421c1200c085343a4784856a 100644
--- a/util/mac/mach_o_image_symbol_table_reader.cc
+++ b/util/mac/mach_o_image_symbol_table_reader.cc
@@ -104,6 +104,7 @@ class MachOImageSymbolTableReaderInitializer {
       return false;
     }
 
+    scoped_ptr<TaskMemory::MappedMemory> string_table;
     for (size_t symbol_index = 0; symbol_index < symbol_count; ++symbol_index) {
       const process_types::nlist& symbol = symbols[symbol_index];
       std::string symbol_info = base::StringPrintf(", symbol index %zu%s",
@@ -121,11 +122,17 @@ class MachOImageSymbolTableReaderInitializer {
           return false;
         }
 
+        if (!string_table) {
+          string_table = process_reader_->Memory()->ReadMapped(
+              strtab_address, strtab_size);
+          if (!string_table) {
+            LOG(WARNING) << "could not read string table" << module_info_;
+            return false;
+          }
+        }
+
         std::string name;
-        if (!process_reader_->Memory()->ReadCStringSizeLimited(
-                strtab_address + symbol.n_strx,
-                strtab_size - symbol.n_strx,
-                &name)) {
+        if (!string_table->ReadCString(symbol.n_strx, &name)) {

[Robert Sesek, 2014/09/10 21:37:40]

This doesn't take into the size limiting anymore. Is that OK?

[Mark Mentovai, 2014/09/10 22:16:55]

rsesek wrote:
It still does. |strtab_size| was the size given when the string table was read
on line 127, and you can only access up to that size through this interface.
ReadCString will return false if you try to read past strtab_size.

           LOG(WARNING) << "could not read string" << symbol_info;
           return false;
         }