Add Android support

[mhsmith]

This will be used by cibuildwheel to replace its limited built-in support for adding external libraries to an Android wheel.

This involves cross-compilation, but it doesn't have much of an overlap with #512. It adds the --ldpaths option, which allows auditwheel to search an arbitrary sysroot, rather than the build machine's own libraries.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.76%. Comparing base (e21df8b) to head (c12866f).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #643      +/-   ##
==========================================
+ Coverage   95.34%   95.76%   +0.41%     
==========================================
  Files          22       23       +1     
  Lines        1870     1935      +65     
  Branches      355      367      +12     
==========================================
+ Hits         1783     1853      +70     
+ Misses         48       46       -2     
+ Partials       39       36       -3     

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[mhsmith]

Yes, in fact my desktop machine uses macOS, so I used it for almost all of my testing. I guess this means we should add a CI job for that platform as well, but I'll wait for your review before I deal with that.

[Copilot]

Pull request overview

This PR extends auditwheel to support auditing/repairing Android wheels (PEP 738) in cross-compilation scenarios, primarily by allowing library discovery via an explicit sysroot search path rather than the build machine’s default linker paths.

Changes:

• Add Android as a supported libc/policy target (new android-policy.json, Android-aware WheelPolicies behavior).
• Introduce --ldpaths to control external library search paths (used by show, repair, and lddtree).
• Update grafting/patching behavior to better support Android RUNPATH semantics; add unit + integration tests and Android fixture wheels/libs.

Reviewed changes

Copilot reviewed 26 out of 29 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/auditwheel/libc.py	Adds Libc.ANDROID and a tag_prefix mapping for platform tag detection.
src/auditwheel/policy/__init__.py	Loads Android policy JSON and selects appropriate policy based on wheel API level tag; Android-specific external ref filtering.
src/auditwheel/policy/android-policy.json	Defines Android library whitelists for selected API levels.
src/auditwheel/options.py	Centralizes shared CLI options; adds --ldpaths.
src/auditwheel/lddtree.py	Adds --ldpaths parsing/handling and improves $ORIGIN expansion rules.
src/auditwheel/wheel_abi.py	Plumbs --ldpaths into ELF analysis and ensures Android analysis doesn’t implicitly use host linker paths.
src/auditwheel/main_show.py / src/auditwheel/main_repair.py / src/auditwheel/main_lddtree.py	Wires --ldpaths into subcommands; adjusts repair flow for new patcher behavior.
src/auditwheel/patcher.py	Makes patchelf behavior platform-aware (Android RUNPATH handling + API-level restriction).
src/auditwheel/repair.py	Sets $ORIGIN rpath/runpath on grafted libraries unconditionally.
src/auditwheel/wheeltools.py	Adds helpers for platform tag extraction and Android API parsing; updates libc/arch detection accordingly.
src/auditwheel/architecture.py	Adds arm64_v8a and normalizes to baseline aarch64.
src/auditwheel/elfutils.py	Adds SONAME reader helper.
Tests (tests/unit/*, tests/integration/*)	Adds Android coverage, --ldpaths coverage, and fixtures for Android wheel repair behavior.
README.rst	Updates messaging to include Android wheels and notes macOS as a potential host for Android wheel work.

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[mayeut]

Just a couple questions/suggestions remain
I think we're almost there, thanks.

[Copilot]

Pull request overview

Copilot reviewed 28 out of 31 changed files in this pull request and generated 1 comment.

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[mayeut]

LGTM !