Initial import of libdpf.

Co-authored-by: Cursor <cursoragent@cursor.com>

thirdparty/hedley/README.md

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+# Hedley
+
+## Documentation
+
+For documentation, see [https://nemequ.github.io/hedley/](https://nemequ.github.io/hedley/).
+There is an easy-to-read user guide and full API documentation.
+
+## Brief Description
+
+Hedley is C/C++ a header file designed to smooth over some
+platform-specific annoyances.  The idea is to get rid of a bunch of
+the #ifdefs in your code and put them in Hedley instead or, if you
+haven't bothered with platform-specific functionality in your code, to
+make it easier to do so.  This code can be used to improve:
+
+ * Static analysis — better warnings and errors help you catch errors
+   before they become a real issue.
+ * Optimizations — compiler hints help speed up your code.
+ * Manage public APIs
+   * Visibility — keeping internal symbols private can make your
+     program faster and smaller.
+   * Versioning — help consumers avoid functions which are deprecated
+     or too new for all the platforms they want to support.
+ * C/C++ interoperability — make it easier to use code in both C and
+   C++ compilers.
+* *… and more!*
+
+You can safely use Hedley in your *public* API.  If someone else
+includes a newer version of Hedley later on, the newer Hedley will
+just redefine everything, and if someone includes an older version it
+will simply be ignored.
+
+It should be safe to use any of Hedley's features; if the platform
+doesn't support the feature it will be silently ignored.