Fix a FORWARD_NULL defect in ExtractModuleName reported by Coverity.

If 'sep' is still NULL after the for loop, ix must be -1, so
ix == 0 cannot be true.

Update the comment for ExtractModuleName in the header to match
the implementation.  I don't see any code that checks whether the
path is a full path.

R=rvargas
BUG=http://crbug.com/17101
TEST=none
Review URL: http://codereview.chromium.org/155979

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@21404 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 5 insertions, 6 deletions

diff --git a/sandbox/src/sandbox_nt_util.cc b/sandbox/src/sandbox_nt_util.cc
index ae5556e..e8a56a7 100644
--- a/sandbox/src/sandbox_nt_util.cc
+++ b/sandbox/src/sandbox_nt_util.cc
@@ -301,7 +301,6 @@ UNICODE_STRING* GetImageInfoFromModule(HMODULE module, uint32* flags) {
         if (headers->OptionalHeader.SizeOfCode)
           *flags |= MODULE_HAS_CODE;
       }
-
     } while (false);
   } __except(EXCEPTION_EXECUTE_HANDLER) {
   }
@@ -349,7 +348,7 @@ UNICODE_STRING* ExtractModuleName(const UNICODE_STRING* module_path) {
   int start_pos = module_path->Length / sizeof(wchar_t) - 1;
   int ix = start_pos;
 
-  for(; ix >= 0; --ix) {
+  for (; ix >= 0; --ix) {
     if (module_path->Buffer[ix] == L'\\') {
       sep = &module_path->Buffer[ix];
       break;
@@ -361,7 +360,7 @@ UNICODE_STRING* ExtractModuleName(const UNICODE_STRING* module_path) {
     return NULL;
 
   // No path separator found. Use the entire name.
-  if ((ix == 0) && !sep) {
+  if (!sep) {
     sep = &module_path->Buffer[-1];
   }
 
diff --git a/sandbox/src/sandbox_nt_util.h b/sandbox/src/sandbox_nt_util.h
index f979a0d..87d2409 100644
--- a/sandbox/src/sandbox_nt_util.h
+++ b/sandbox/src/sandbox_nt_util.h
@@ -118,9 +118,9 @@ UNICODE_STRING* GetImageInfoFromModule(HMODULE module, uint32* flags);
 UNICODE_STRING* GetBackingFilePath(PVOID address);
 
 // Returns the last component of a path that contains the module name.
-// It will return NULL if the path is not a full path or if the path ends
-// with the path separator. The returned buffer must be freed with a placement
-// delete (see GetImageNameFromModule example).
+// It will return NULL if the path ends with the path separator. The returned
+// buffer must be freed with a placement delete (see GetImageNameFromModule
+// example).
 UNICODE_STRING* ExtractModuleName(const UNICODE_STRING* module_path);
 
 // Returns true if the parameters correspond to a dll mapped as code.