[llvm-commits] [PATCH] Have ReExec read environment from /proc/self/environ

[Peter Collingbourne]

================
Comment at: lib/sanitizer_common/sanitizer_linux.cc:204
@@ -203,5 +203,3 @@
 
-void ReExec() {
-  static const int kMaxArgv = 100;
-  InternalScopedBuffer<char*> argv(kMaxArgv + 1);
-  static char *buff;
+static void ReadNullSepFileToArray(const char *path, char ***arr, int arr_size){
+  char *buff;
----------------
Reid Kleckner wrote:
> Isn't /proc unavailable in many contexts, like chroots?  I believe function pointers in preinit_array receive argc, argv, and envp as arguments, which are forwarded straight from what the kernel put on the stack.  You may be able to use that instead.
> Isn't /proc unavailable in many contexts, like chroots?

I'm not convinced that we care enough about these contexts that we need to support them.  Besides, this code already has a dependency on /proc.

> I believe function pointers in preinit_array receive argc, argv, and envp as arguments, which are forwarded straight from what the kernel put on the stack. You may be able to use that instead.

The trouble is that (e.g.) __msan_init may be called from contexts from which we don't have access to these.  Perhaps one of the msan developers can enlighten us as to why .preinit_array isn't being used for msan.


http://llvm-reviews.chandlerc.com/D304