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  1. 30a856c Use ro.hw_timeout_multiplier for hidl_lazy_test. by Florian Mayer · 9 weeks ago master
  2. 93704e3 Fix newer Bison compatibility by Dan Willemsen · 9 weeks ago
  3. 9631db1 Add hidl to hwasan-postsubmit by Florian Mayer · 2 months ago
  4. 261070e Merge "Suppress int-in-bool-context warning" by Yi Kong · 2 months ago
  5. d5f1208 Suppress int-in-bool-context warning by Yi Kong · 3 months ago


Full documentation can be found here:

hidl-gen is a compiler for the HIDL (HAL Interface Design Language) which generates C++ and Java endpoints for RPC mechanisms. The main userspace libraries which this compiler uses can be found at system/libhidl.

1. Build

m hidl-gen

2. Run

Note that options for hidl-gen expected to be invoked by the build system are marked with ‘internal’ in the help menu.

hidl-gen -h

hidl-gen -o output -L c++-impl -r android.hardware:hardware/interfaces -r android.hidl:system/libhidl/transport android.hardware.nfc@1.0

Some defaults for package roots are also provided

hidl-gen -o output -L c++-impl android.hardware.nfc@1.0
hidl-gen -o output -L vts android.hardware.nfc@1.0
hidl-gen -L hash android.hardware.nfc@1.0

Example command for vendor project

hidl-gen -L c++-impl -r

See and for examples of how to generate HIDL makefiles (using the -Landroidbp option).

NOTE: When using the -Landroidbp option, you can force generated modules to be installed in /system_ext rather than other partition by putting a marker file .hidl_for_system_ext alongside *.hal files.

NOTE: You can also install the vendor variant of the generated modules to be installed in /odm rather than /vendor by putting a marker file .hidl_for_odm alongside *.hal files.


This is a helper tool to convert C headers to valid .hal files.

m c2hal && c2hal -h