commit	19a5748ef4e62d3767980bdff590b53b35137b85	[log] [tgz]
author	Austin Sullivan <asully@chromium.org>	Thu Apr 14 21:41:24 2022
committer	Copybara-Service <copybara-worker@google.com>	Thu Apr 14 21:51:32 2022
tree	c77b19279272c3ac34866549b931db4dfd70def1
parent	d1a0e9287daacf1adb17aa7544c4a5ac80a14de5 [diff]

tree: c77b19279272c3ac34866549b931db4dfd70def1

README.md

Chromium SQLite.

This is the top folder for Chromium's SQLite. The actual SQLite source is not in this repository, but instead cloned into the src directory from https://chromium.googlesource.com/chromium/deps/sqlite.

The directory structure is as follows. Files common to all third_party projects (ex. BUILD.GN, OWNERS, LICENSE) are omitted.

src/ The Chromium fork of SQLite (cloned via top level DEPS file).
scripts/ Scripts that generate the files in the amalgamations in src/.
sqlite.h The header used by the rest of Chromium to include SQLite. This forwards to src/amalgamation/sqlite3.h
fuzz/ Google OSS-Fuzz (ClusterFuzz) testing for Chromium's SQLite build.

Amalgamations

SQLite amalgamations are committed to the SQLite Chromium repository (in src), but are created by a script that lives in the Chromium repository. This is because the configuration variables for building and amalgamation generation are shared.

There are two amalgamations:

//third_party/sqlite/src/amalgamation is shipped, tested, and Fuzzed by Chromium.
//third_party/sqlite/src/amalgamation_dev is not distributed or tested by Chromium. It is used for some developer tools (either only for local development, or only on trusted input).

//third_party/sqlite/src repository.

CLs in this repository cannot be submitted through the commit queue (ex. CQ+2), because there is no commit queue / try bot support for this repository. Please use the “Submit” button (in Gerrit's 3-dot menu on the top right) to submit CLs in this repository instead.

Playbook

Upgrade to a new SQLite release.

SQLite should be upgraded as soon as possible whenever a new version is available. This is because new versions often contain security and stability improvements, and frequent upgrades allow Chromium to have minimal cherry-pick diffs when requesting investigation for SQLite bugs discovered by Chromium Fuzzers. New versions may be viewed at https://www.sqlite.org/news.html, and bugs for these upgrades may look like this example.

Historically, Chromium fuzzers often find issues within 2 weeks after upgrading to new SQLite versions. Avoid upgrading SQLite within 1-2 weeks of a Chromium branch point to allow fuzzers time to run. However, if the new SQLite release contains known security or stability fixes, upgrade once available and monitor fuzzers more closely.

SQLite version upgrades tend to be extremely large changes (example), for which the diffs are not possible to thoroughly review.

Note SQLite tags all releases version-<release number>, e.g. version-3.33.0. The Chromium project prefixes all tags/branches with “chromium-”, e.g. chromium-version-3.33.0.

Create new release branch
Use the SQLite git commit hash for the release, found at sqlite/tags, when creating a new release branch. For example, “562fd18b9dc27216191c0a6477bba9b175f7f0d2” corresponds to the 3.31.1 release. The commit is used instead of the tag name because we do not mirror the SQLite tags along with the commits.
Create the branch at Gerrit/branches.
Note: To create a release branch, you must be listed as a member in the sqlite-owners Gerrit group

Checkout the new Chromium release branch.

Get the version from the README.chromium.

cd //third_party/sqlite/src
git fetch origin
export VERSION=3.33.0
git checkout -b chromium-version-$VERSION \
    --track origin/chromium-version-$VERSION
git rebase

Generate and commit the SQLite amalgamations.

./../scripts/generate_amalgamation.py
git add amalgamation amalgamation_dev
git commit -m "Amalgamations for release $VERSION"

Run local tests.
Follow steps in Running Tests below to execute all verifications and tests.
Upload the new release branch for review.
```
git cl upload
```
Roll the Chromium DEPS file.
Once review above has merged:
1. Roll the chromium/src/DEPS file to reference that new commit hash.
```
roll-dep src/third_party/sqlite/src --roll-to <git hash of merged CL>
```
2. Update the version in //third_party/sqlite/README.chromium. Amend the commit created by roll-dep above.

Cherry-pick unreleased commit from SQLite.

Sometimes critical fixes land in SQLite's master, but are not yet in a release. This may occur when other SQLite embedders find critical security or stability issues that SQLite authors then fix, but are often detected by Chromium ClusterFuzz as well.

If you're triaging a ClusterFuzz bug, an internal playbook on how to triage and fix ClusterFuzz bugs is available at go/sqlite-clusterfuzz-bug-process.

If changes need to be brought into the current release branch, please do the following:

Checkout the current release branch.

Get the version from the README.chromium.

export VERSION=3.33.0
cd //third_party/sqlite/src
git checkout -b chromium-version-$VERSION \
  --track origin/chromium-version-$VERSION

Cherry-pick the change
Git can be used to cherry pick upstream changes into a release branch but the sqlite_cherry_picker.py script is preferred. This script automates a few tasks such as:
- Identifying the correct Git commit hash to use if given the Fossil commit hash.
- Automatically calculating Fossil manifest hashes.
- Skipping conflicted binary files.
- Generating the amalgamations.
Cherry-pick the commit:
```
../scripts/sqlite_cherry_picker.py <full git or fossil commit hash>
```
If there is a conflict that the script cannot resolve then, like git cherry-pick, the script will exit and leave you to resolve the conflicts. Once resolved run the script a second time:
```
../scripts/sqlite_cherry_picker.py --continue
```
If you have access to the SQLite fossil commit hash, and would like to map this to the corresponding git hash, you can use GitHub search. As SQLite‘s git repository’s commits include the fossil hash, you can search for the fossil hash, using the following query with the fossil commit hash appended (example search): https://github.com/sqlite/sqlite/search?type=commits&q=
If the cherry-picking script is unable to cherry-pick a commit, like in https://crbug.com/1162100, manually apply the change from a SQLite or git, in //third_party/sqlite/src's files modified in the SQLite tracker, like at https://sqlite.org/src/info/a0bf931bd712037e. From there, run ../scripts/generate_amalgamation.py to propagate these changes over to the amalgamation files. sqlite_cherry_picker.py should generally be preferred, as it updates hashes and simplifies tracking.
Run local tests.
Follow steps in Running Tests below to execute all verifications and tests.
Upload cherry-picked change (with amalgamations) for review.

If the relevant bug is a security bug, make sure that the reviewers are cc‘ed. Otherwise, they may not know what/why they’re reviewing.

```sh
git cl upload
```

Update the Chromium DEPS file.
Once review above has merged, roll the chromium/src/DEPS file to reference that new commit hash.
```
roll-dep src/third_party/sqlite/src --roll-to <git hash of merged CL>
```

Running Tests

Build all desktop targets:

Check that extract_sqlite_api.py added “chrome_” to all exported symbols. Only “_fini” and “_init” should be unprefixed, but are conditionally exported by the linker and may be omitted.

autoninja -C out/Default
nm -B out/Default/libchromium_sqlite3.so | cut -c 18- | sort | grep '^T'

Running unit tests

out/Default/sql_unittests

Running web tests

third_party/blink/tools/run_web_tests.py -t Default storage/websql/

Running SQLite's TCL test suite within the Chromium checkout.

This is one of the SQLite test suites. They take approximately 3 minutes to build and run on a fast workstation.

Note: Tests currently fail both locally and on Chromium release branches. They fail on release branches because some tests rely on SQLite databases (binary files) which are committed to the source and are likely not merged down when cherry picked. It is safe to ignore these errors which should be reasonably easy to identify based on the cherry picked upstream changes. Until these tests are fixed, it is safe to ignore these tests when running SQLite test suites.

cd //third_party/sqlite
./scripts/generate_amalgamation.py --testing
make --directory=src test | tee /tmp/test.log

Show tests with errors:

egrep 'errors out of' /tmp/test.log

Show broken tests:

egrep 'Failures on these tests:' /tmp/test.log

Broken tests will also show lines ending in “...” instead of “... Ok”.

When done, clean up the SQLite repository:

cd src
make clean
git clean -i  # and delete everything
rm -rf testdir
git checkout amalgamation/sqlite3.c
git checkout amalgamation_dev/sqlite3.c