[compiler-rt] [sanitizer_common] Implement address sanitizer on AIX: add platform specific functionality (4/n) (PR #131868)

[Hubert Tong via llvm-commits]

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@@ -0,0 +1,212 @@
+//===-- sanitizer_procmaps_aix.cpp ----------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// Information about the process mappings (AIX-specific parts).
+//===----------------------------------------------------------------------===//
+
+#include "sanitizer_platform.h"
+
+#if SANITIZER_AIX
+#  include <stdio.h>
+
+#  include "sanitizer_common.h"
+#  include "sanitizer_file.h"
+#  include "sanitizer_procmaps.h"
+
+namespace __sanitizer {
+
+static bool IsOneOf(char c, char c1, char c2) { return c == c1 || c == c2; }
+
+void ReadProcMaps(ProcSelfMapsBuff *proc_maps) {
+  uptr pid = internal_getpid();
+
+  // The mapping in /proc/id/map is not ordered by address, this will hit some
+  // issue when checking stack base and size. Howevern AIX procmap can generate
+  // sorted ranges.
+  char Command[100] = {};
+
+  internal_snprintf(Command, 100, "procmap -qX %d", pid);
----------------
hubert-reinterpretcast wrote:

@jakeegan, I am aware that @mandlebug was working on an implementation that parses `/proc/$$/map` instead of calling the `procmap` utility.

Additionally, calling the `procmap` utility without an explicitly-qualified pathname introduces the possibility that a `procmap` other than the intended one would be used.

https://github.com/llvm/llvm-project/pull/131868