feat: added file capability [APMSP-3780] by Aaalibaba42 · Pull Request #2240 · DataDog/libdatadog

Aaalibaba42 · 2026-07-15T09:59:06Z

What does this PR do?

Added Capability to read, write, and have metadata about files

Motivation

dd-trace-js needing to add info from the /proc in their requests, it's better to have libdatadog drive the call

Additional Notes

Nop

How to test the change?

check, tests, check for wasm32

github-actions · 2026-07-15T10:01:00Z

📚 Documentation Check Results

⚠️ 236 documentation warning(s) found

📦 `libdd-capabilities-impl` - 205 warning(s)

📦 `libdd-capabilities` - 31 warning(s)

Updated: 2026-07-21 11:56:55 UTC | Commit: dfda3f1 | missing-docs job results

github-actions · 2026-07-15T10:02:50Z

🔒 Cargo Deny Results

⚠️ 1 issue(s) found, showing only errors (advisories, bans, sources)

📦 `libdd-capabilities-impl` - 1 error(s)

Show output

error[unsound]: Rand is unsound with a custom logger using `rand::rng()`
   ┌─ /home/runner/work/libdatadog/libdatadog/Cargo.lock:68:1
   │
68 │ rand 0.8.5 registry+https://github.com/rust-lang/crates.io-index
   │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ unsound advisory detected
   │
   ├ ID: RUSTSEC-2026-0097
   ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2026-0097
   ├ It has been reported (by [@lopopolo](https://github.com/lopopolo)) that the `rand` library is [unsound](https://rust-lang.github.io/unsafe-code-guidelines/glossary.html#soundness-of-code--of-a-library) (i.e. that safe code using the public API can cause Undefined Behaviour) when all the following conditions are met:
     
     - The `log` and `thread_rng` features are enabled
     - A [custom logger](https://docs.rs/log/latest/log/#implementing-a-logger) is defined
     - The custom logger accesses `rand::rng()` (previously `rand::thread_rng()`) and calls any `TryRng` (previously `RngCore`) methods on `ThreadRng`
     - The `ThreadRng` (attempts to) reseed while called from the custom logger (this happens every 64 kB of generated data)
     - Trace-level logging is enabled or warn-level logging is enabled and the random source (the `getrandom` crate) is unable to provide a new seed
     
     `TryRng` (previously `RngCore`) methods for `ThreadRng` use `unsafe` code to cast `*mut BlockRng<ReseedingCore>` to `&mut BlockRng<ReseedingCore>`. When all the above conditions are met this results in an aliased mutable reference, violating the Stacked Borrows rules. Miri is able to detect this violation in sample code. Since construction of [aliased mutable references is Undefined Behaviour](https://doc.rust-lang.org/stable/nomicon/references.html), the behaviour of optimized builds is hard to predict.
   ├ Announcement: https://github.com/rust-random/rand/pull/1763
   ├ Solution: Upgrade to >=0.10.1 OR <0.10.0, >=0.9.3 OR <0.9.0, >=0.8.6 (try `cargo update -p rand`)
   ├ rand v0.8.5
     └── (dev) libdd-common v5.1.0
         └── libdd-capabilities-impl v3.0.0

advisories FAILED, bans ok, sources ok

📦 `libdd-capabilities` - ✅ No issues

Updated: 2026-07-21 11:58:48 UTC | Commit: dfda3f1 | dependency-check job results

datadog-prod-us1-6 · 2026-07-15T10:03:47Z

Tests

🎉 All green!

🧪 All tests passed
❄️ No new flaky tests detected

🎯 Code Coverage (details)
• Patch Coverage: 75.97%
• Overall Coverage: 74.54% (-0.01%)

_{This comment will be updated automatically if new data arrives.

🔗 Commit SHA: 91a4834 | Docs | Datadog PR Page | Give us feedback!}

dd-octo-sts · 2026-07-15T10:44:44Z

Artifact Size Benchmark Report

aarch64-alpine-linux-musl

Artifact	Baseline	Commit	Change
/aarch64-alpine-linux-musl/lib/libdatadog_profiling.a	88.03 MB	88.04 MB	+0% (+1.28 KB) 👌
/aarch64-alpine-linux-musl/lib/libdatadog_profiling.so	8.13 MB	8.13 MB	0% (0 B) 👌

aarch64-unknown-linux-gnu

Artifact	Baseline	Commit	Change
/aarch64-unknown-linux-gnu/lib/libdatadog_profiling.a	99.31 MB	99.31 MB	+0% (+376 B) 👌
/aarch64-unknown-linux-gnu/lib/libdatadog_profiling.so	10.86 MB	10.86 MB	+0% (+160 B) 👌

libdatadog-x64-windows

Artifact	Baseline	Commit	Change
/libdatadog-x64-windows/debug/dynamic/datadog_profiling_ffi.dll	26.55 MB	26.55 MB	+0% (+512 B) 👌
/libdatadog-x64-windows/debug/dynamic/datadog_profiling_ffi.lib	89.18 KB	89.18 KB	0% (0 B) 👌
/libdatadog-x64-windows/debug/dynamic/datadog_profiling_ffi.pdb	191.10 MB	191.23 MB	+.06% (+128.00 KB) 🔍
/libdatadog-x64-windows/debug/static/datadog_profiling_ffi.lib	1.04 GB	1.04 GB	--.01% (-110.73 KB) 💪
/libdatadog-x64-windows/release/dynamic/datadog_profiling_ffi.dll	8.65 MB	8.65 MB	+0% (+512 B) 👌
/libdatadog-x64-windows/release/dynamic/datadog_profiling_ffi.lib	89.18 KB	89.18 KB	0% (0 B) 👌
/libdatadog-x64-windows/release/dynamic/datadog_profiling_ffi.pdb	25.31 MB	25.31 MB	0% (0 B) 👌
/libdatadog-x64-windows/release/static/datadog_profiling_ffi.lib	50.49 MB	50.49 MB	+0% (+256 B) 👌

libdatadog-x86-windows

Artifact	Baseline	Commit	Change
/libdatadog-x86-windows/debug/dynamic/datadog_profiling_ffi.dll	23.13 MB	23.13 MB	0% (0 B) 👌
/libdatadog-x86-windows/debug/dynamic/datadog_profiling_ffi.lib	90.58 KB	90.58 KB	0% (0 B) 👌
/libdatadog-x86-windows/debug/dynamic/datadog_profiling_ffi.pdb	195.80 MB	195.92 MB	+.05% (+120.00 KB) 🔍
/libdatadog-x86-windows/debug/static/datadog_profiling_ffi.lib	1.03 GB	1.03 GB	+.04% (+489.62 KB) 🔍
/libdatadog-x86-windows/release/dynamic/datadog_profiling_ffi.dll	6.67 MB	6.67 MB	0% (0 B) 👌
/libdatadog-x86-windows/release/dynamic/datadog_profiling_ffi.lib	90.58 KB	90.58 KB	0% (0 B) 👌
/libdatadog-x86-windows/release/dynamic/datadog_profiling_ffi.pdb	27.22 MB	27.22 MB	0% (0 B) 👌
/libdatadog-x86-windows/release/static/datadog_profiling_ffi.lib	48.06 MB	48.06 MB	+0% (+302 B) 👌

x86_64-alpine-linux-musl

Artifact	Baseline	Commit	Change
/x86_64-alpine-linux-musl/lib/libdatadog_profiling.a	78.53 MB	78.53 MB	+0% (+1.90 KB) 👌
/x86_64-alpine-linux-musl/lib/libdatadog_profiling.so	9.04 MB	9.04 MB	0% (0 B) 👌

x86_64-unknown-linux-gnu

Artifact	Baseline	Commit	Change
/x86_64-unknown-linux-gnu/lib/libdatadog_profiling.a	94.02 MB	94.02 MB	+0% (+1.25 KB) 👌
/x86_64-unknown-linux-gnu/lib/libdatadog_profiling.so	11.00 MB	11.00 MB	+0% (+144 B) 👌

pr-commenter · 2026-07-15T11:01:43Z

Benchmarks

Comparison

Benchmark execution time: 2026-07-21 10:38:18

Comparing candidate commit 41e89a1 in PR branch jwiriath/file-caps with baseline commit fb65e46 in branch main.

Found 0 performance improvements and 0 performance regressions! Performance is the same for 142 metrics, 0 unstable metrics.

Explanation

This is an A/B test comparing a candidate commit's performance against that of a baseline commit. Performance changes are noted in the tables below as:

🟩 = significantly better candidate vs. baseline
🟥 = significantly worse candidate vs. baseline

We compute a confidence interval (CI) over the relative difference of means between metrics from the candidate and baseline commits, considering the baseline as the reference.

If the CI is entirely outside the configured SIGNIFICANT_IMPACT_THRESHOLD (or the deprecated UNCONFIDENCE_THRESHOLD), the change is considered significant.

Feel free to reach out to #apm-benchmarking-platform on Slack if you have any questions.

More details about the CI and significant changes

You can imagine this CI as a range of values that is likely to contain the true difference of means between the candidate and baseline commits.

CIs of the difference of means are often centered around 0%, because often changes are not that big:

---------------------------------(------|---^--------)-------------------------------->
                              -0.6%    0%  0.3%     +1.2%
                                 |          |        |
         lower bound of the CI --'          |        |
sample mean (center of the CI) -------------'        |
         upper bound of the CI ----------------------'

As described above, a change is considered significant if the CI is entirely outside the configured SIGNIFICANT_IMPACT_THRESHOLD (or the deprecated UNCONFIDENCE_THRESHOLD).

For instance, for an execution time metric, this confidence interval indicates a significantly worse performance:

----------------------------------------|---------|---(---------^---------)---------->
                                       0%        1%  1.3%      2.2%      3.1%
                                                  |   |         |         |
       significant impact threshold --------------'   |         |         |
                      lower bound of CI --------------'         |         |
       sample mean (center of the CI) --------------------------'         |
                      upper bound of CI ----------------------------------'

Benchmark execution time: 2026-07-21 10:53:43

Comparing candidate commit 41e89a1 in PR branch jwiriath/file-caps with baseline commit fb65e46 in branch main.

Found 3 performance improvements and 18 performance regressions! Performance is the same for 156 metrics, 10 unstable metrics.

Explanation

This is an A/B test comparing a candidate commit's performance against that of a baseline commit. Performance changes are noted in the tables below as:

🟩 = significantly better candidate vs. baseline
🟥 = significantly worse candidate vs. baseline

We compute a confidence interval (CI) over the relative difference of means between metrics from the candidate and baseline commits, considering the baseline as the reference.

If the CI is entirely outside the configured SIGNIFICANT_IMPACT_THRESHOLD (or the deprecated UNCONFIDENCE_THRESHOLD), the change is considered significant.

Feel free to reach out to #apm-benchmarking-platform on Slack if you have any questions.

More details about the CI and significant changes

You can imagine this CI as a range of values that is likely to contain the true difference of means between the candidate and baseline commits.

CIs of the difference of means are often centered around 0%, because often changes are not that big:

---------------------------------(------|---^--------)-------------------------------->
                              -0.6%    0%  0.3%     +1.2%
                                 |          |        |
         lower bound of the CI --'          |        |
sample mean (center of the CI) -------------'        |
         upper bound of the CI ----------------------'

As described above, a change is considered significant if the CI is entirely outside the configured SIGNIFICANT_IMPACT_THRESHOLD (or the deprecated UNCONFIDENCE_THRESHOLD).

For instance, for an execution time metric, this confidence interval indicates a significantly worse performance:

----------------------------------------|---------|---(---------^---------)---------->
                                       0%        1%  1.3%      2.2%      3.1%
                                                  |   |         |         |
       significant impact threshold --------------'   |         |         |
                      lower bound of CI --------------'         |         |
       sample mean (center of the CI) --------------------------'         |
                      upper bound of CI ----------------------------------'

scenario:alloc_free/sampled_system_fast_path/4096

🟩 execution_time [-11.159ns; -11.003ns] or [-10.743%; -10.593%]

scenario:alloc_free/system/4096

🟥 execution_time [+14.457ns; +14.590ns] or [+18.094%; +18.261%]

scenario:ddsketch_add/add/clustered_near_zero

🟥 execution_time [+71.440µs; +72.700µs] or [+59.669%; +60.721%]
🟥 throughput [-12969056.160op/s; -12754811.828op/s] or [-37.893%; -37.267%]

scenario:ddsketch_add/add/collapsing

🟥 execution_time [+114.912µs; +118.808µs] or [+82.321%; +85.112%]
🟥 throughput [-13451825.113op/s; -13187550.013op/s] or [-45.843%; -44.942%]

scenario:ddsketch_add/add/large_values

🟥 execution_time [+73.122µs; +74.216µs] or [+61.058%; +61.972%]
🟥 throughput [-13078257.444op/s; -12959747.426op/s] or [-38.237%; -37.891%]

scenario:ddsketch_add/add/mixed

🟥 execution_time [+85.037µs; +89.214µs] or [+70.538%; +74.004%]
🟥 throughput [-14341157.105op/s; -13979650.218op/s] or [-42.209%; -41.145%]

scenario:ddsketch_add/add_with_count/clustered_near_zero

🟥 execution_time [+72.882µs; +73.093µs] or [+60.731%; +60.907%]
🟥 throughput [-12924038.396op/s; -12891211.493op/s] or [-37.866%; -37.770%]

scenario:ddsketch_add/add_with_count/collapsing

🟥 execution_time [+124.733µs; +126.473µs] or [+88.450%; +89.684%]
🟥 throughput [-13725651.927op/s; -13623284.410op/s] or [-47.256%; -46.903%]

scenario:ddsketch_add/add_with_count/large_values

🟥 execution_time [+72.013µs; +72.372µs] or [+59.468%; +59.765%]
🟥 throughput [-12663359.965op/s; -12603947.100op/s] or [-37.437%; -37.262%]

scenario:ddsketch_add/add_with_count/mixed

🟥 execution_time [+95.476µs; +99.370µs] or [+78.487%; +81.689%]
🟥 throughput [-15063339.923op/s; -14735753.654op/s] or [-44.736%; -43.763%]

scenario:glob_matcher/ascii_wildcard_question_match/wall_time

🟩 execution_time [-21.079ns; -21.061ns] or [-36.375%; -36.345%]

scenario:glob_matcher/ascii_wildcard_star_match/wall_time

🟩 execution_time [-23.551ns; -23.525ns] or [-38.979%; -38.936%]

scenario:receiver_entry_point/report/2644

🟥 execution_time [+204.057µs; +209.374µs] or [+5.660%; +5.808%]

Candidate

Omitted due to size.

Baseline

Omitted due to size.

Aaalibaba42 · 2026-07-20T12:24:09Z

/merge

gh-worker-devflow-routing-ef8351 · 2026-07-20T12:24:12Z

View all feedbacks in Devflow UI.

2026-07-20 12:24:12 UTC ℹ️ Start processing command /merge

2026-07-20 12:24:19 UTC ℹ️ MergeQueue: waiting for PR to be ready

This pull request is not mergeable according to GitHub. Common reasons include pending required checks, missing approvals, or merge conflicts — but it could also be blocked by other repository rules or settings.
It will be added to the queue as soon as checks pass and/or get approvals. View in MergeQueue UI.
Note: if you pushed new commits since the last approval, you may need additional approval.
You can remove it from the waiting list with /remove command.

2026-07-20 13:17:10 UTC ℹ️ MergeQueue: merge request added to the queue

The expected merge time in main is approximately 1h (p90).

2026-07-20 13:44:06 UTC ℹ️ MergeQueue: Readding this merge request to the queue because another merge request processed with yours failed. No action is needed from your side.

2026-07-20 14:33:56 UTC ❌ MergeQueue: The checks failed on this merge request

Tests failed on this commit d24f70b:

allchecks

What to do next?

Investigate the failures and when ready, re-add your pull request to the queue!
If your PR checks are green, try to rebase/merge. It might be because the CI run is a bit old.
Any question, go check the FAQ.

Aaalibaba42 · 2026-07-20T15:09:11Z

/merge

gh-worker-devflow-routing-ef8351 · 2026-07-20T15:09:16Z

View all feedbacks in Devflow UI.

2026-07-20 15:09:16 UTC ℹ️ Start processing command /merge

2026-07-20 15:09:21 UTC ℹ️ MergeQueue: pull request added to the queue

The expected merge time in main is approximately 1h (p90).

2026-07-20 15:55:41 UTC ❌ MergeQueue: The checks failed on this merge request

Tests failed on this commit 9c84f5f:

What to do next?

Investigate the failures and when ready, re-add your pull request to the queue!
If your PR checks are green, try to rebase/merge. It might be because the CI run is a bit old.
Any question, go check the FAQ.

Aaalibaba42 · 2026-07-20T16:48:33Z

/merge

gh-worker-devflow-routing-ef8351 · 2026-07-20T16:48:38Z

View all feedbacks in Devflow UI.

2026-07-20 16:48:38 UTC ℹ️ Start processing command /merge

2026-07-20 16:48:45 UTC ℹ️ MergeQueue: waiting for PR to be ready

This pull request is not mergeable according to GitHub. Common reasons include pending required checks, missing approvals, or merge conflicts — but it could also be blocked by other repository rules or settings.
It will be added to the queue as soon as checks pass and/or get approvals. View in MergeQueue UI.
Note: if you pushed new commits since the last approval, you may need additional approval.
You can remove it from the waiting list with /remove command.

2026-07-20 21:04:14 UTC ⚠️ MergeQueue: This merge request was unqueued

devflow unqueued this merge request: It did not become mergeable within the expected time

Aaalibaba42 requested review from a team as code owners July 15, 2026 09:59

Aaalibaba42 force-pushed the jwiriath/file-caps branch from 083f9c2 to 8e15735 Compare July 15, 2026 10:00

Aaalibaba42 force-pushed the jwiriath/file-caps branch from 8e15735 to 1a4ea68 Compare July 15, 2026 10:06

Aaalibaba42 changed the title ~~feat: added file capability~~ feat: added file capability [APMSP-3780] Jul 15, 2026

Aaalibaba42 force-pushed the jwiriath/file-caps branch from d794743 to cc69e41 Compare July 16, 2026 09:29

Aaalibaba42 added 2 commits July 17, 2026 11:36

feat: added file capability

0128826

chore: fmt

241117c

Aaalibaba42 force-pushed the jwiriath/file-caps branch from cc69e41 to 241117c Compare July 17, 2026 09:37

VianneyRuhlmann approved these changes Jul 20, 2026

View reviewed changes

Comment thread libdd-capabilities-impl/src/file.rs Outdated

yannham approved these changes Jul 20, 2026

View reviewed changes

Comment thread libdd-capabilities-impl/src/file.rs Outdated

chore: remove inmemoryfs mocks since we don't use them currently

0a022c8

gh-worker-dd-devflow-36fce6 Bot added mergequeue-status: waiting mergequeue-status: queued mergequeue-status: in_progress mergequeue-status: retrying and removed mergequeue-status: waiting mergequeue-status: queued mergequeue-status: in_progress mergequeue-status: retrying labels Jul 20, 2026

gh-worker-devflow-routing-ef8351 Bot mentioned this pull request Jul 20, 2026

feat(telemetry)!: make telemetry worker wasm-compatible for the TraceExporter #2172

Merged

gh-worker-dd-devflow-36fce6 Bot removed the mergequeue-status: in_progress label Jul 20, 2026

gh-worker-dd-devflow-36fce6 Bot added the mergequeue-status: rejected label Jul 20, 2026

gh-worker-dd-devflow-36fce6 Bot added mergequeue-status: queued mergequeue-status: in_progress mergequeue-status: rejected and removed mergequeue-status: rejected mergequeue-status: queued mergequeue-status: in_progress labels Jul 20, 2026

Merge branch 'main' into jwiriath/file-caps

0f2e775

gh-worker-dd-devflow-36fce6 Bot added mergequeue-status: waiting mergequeue-status: removed and removed mergequeue-status: rejected mergequeue-status: waiting labels Jul 20, 2026

Aaalibaba42 added 2 commits July 21, 2026 12:05

Merge branch 'main' into jwiriath/file-caps

41e89a1

Merge branch 'main' into jwiriath/file-caps

91a4834

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Conversation

Aaalibaba42 commented Jul 15, 2026

What does this PR do?

Motivation

Additional Notes

How to test the change?

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📚 Documentation Check Results

📦 libdd-capabilities-impl - 205 warning(s)

📦 libdd-capabilities - 31 warning(s)

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🔒 Cargo Deny Results

📦 libdd-capabilities-impl - 1 error(s)

📦 libdd-capabilities - ✅ No issues

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Artifact Size Benchmark Report

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Benchmarks

Comparison

Explanation

More details about the CI and significant changes

Explanation

More details about the CI and significant changes

scenario:alloc_free/sampled_system_fast_path/4096

scenario:alloc_free/system/4096

scenario:ddsketch_add/add/clustered_near_zero

scenario:ddsketch_add/add/collapsing

scenario:ddsketch_add/add/large_values

scenario:ddsketch_add/add/mixed

scenario:ddsketch_add/add_with_count/clustered_near_zero

scenario:ddsketch_add/add_with_count/collapsing

scenario:ddsketch_add/add_with_count/large_values

scenario:ddsketch_add/add_with_count/mixed

scenario:glob_matcher/ascii_wildcard_question_match/wall_time

scenario:glob_matcher/ascii_wildcard_star_match/wall_time

scenario:receiver_entry_point/report/2644

Candidate

Baseline

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Aaalibaba42 commented Jul 20, 2026

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github-actions Bot commented Jul 15, 2026 •

edited

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📦 `libdd-capabilities-impl` - 205 warning(s)

📦 `libdd-capabilities` - 31 warning(s)

github-actions Bot commented Jul 15, 2026 •

edited

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📦 `libdd-capabilities-impl` - 1 error(s)

📦 `libdd-capabilities` - ✅ No issues

datadog-prod-us1-6 Bot commented Jul 15, 2026 •

edited by datadog-datadog-prod-us1 Bot

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