qbit-document-generation/renderer/vendor/PATCHES.md

# Zint 2.16.0 + QQQ patchset p1

Provider identity: `zint-2.16.0-qqq-p1`. This is **not unmodified Zint 2.16.0**.
The CLI's upstream version output remains 2.16.0; the wrapper also requires the
fixed patchset identity file, and the host pins the qualified immutable image.
The original tagged archive remains untouched and accompanies the applied-source
archive, input/patch/preimage/postimage hashes, build script and compiler/package
records. `inputs.sha256` is the complete ordered-input integrity inventory.

Apply order (build aborts unless every source preimage and postimage matches):

1. `zint-dotcode-local.patch`: **LOCALLY AUTHORED EQUIVALENT BACKPORT**, not a
   downloaded upstream patch. Changes only `length > 2` to `length >= 2` in the
   non-GS1, no-ECI, initial two-digit condition in `backend/dotcode.c`. This is
   semantically equivalent to the already-reviewed correction in upstream
   [eea16e1a89d1ca32326d78349a7007ab45524c83](https://github.com/zint/zint/commit/eea16e1a89d1ca32326d78349a7007ab45524c83).
   It restores the FNC1 codeword used to identify plain numeric DotCode content.
2. `zint-raster-applied.patch`: exact three `backend/raster.c` source hunks from
   the retained, verbatim `zint-raster-92e9400.patch`, upstream
   [92e94009b2b4db0db9a707f7e33c88b7b1fae5cd](https://github.com/zint/zint/commit/92e94009b2b4db0db9a707f7e33c88b7b1fae5cd).
   Replaces the midpoint circle implementation with the MIT-derived routine and
   corrects the line algorithm attribution. Binary MaxiCode PNG fixture hunks
   are excluded: this native build disables PNG. The compiled native MaxiCode
   implementation does change, although the QQQ wrapper continues routing
   MaxiCode exclusively through its unchanged Okapi provider.
3. `zint-notices-local.patch`: explicit local adaptation of the same upstream
   attribution change to the tag's older freeform `debian/copyright`. The upstream
   copyright hunk targets a later machine-readable file and cannot apply to this
   tag. The original text is preserved and a BSD/MIT attribution addendum plus
   complete MIT notice is appended. `MIT-ZINGL.txt` and the exact upstream
   `zint-copyright-92e9400.txt` accompany it. This adaptation is not described as
   a byte-identical full upstream patch.

The build verifies `inputs.sha256`, all three source preimages, applies patches
with `--batch --forward --fuzz=0`, then verifies all postimages before compiling.
It packages both `zint-2.16.0.tar.gz` and the complete
`zint-2.16.0-qqq-p1-applied.tar.gz`, so recipients can inspect or rebuild the actual
modified source. No local modifications are omitted from corresponding source.

Regression provenance: upstream reviewed test evidence supplies `00` codewords
`6B 00` (default), `6B 00 6A` (13 columns), and 35 words beginning `6B 00` followed
by padding `6A` (200 columns). The `12` expectation `6B 0C` with equivalent padding
is an independently derived regression from the same numeric Code C rule, **not
an observed upstream vector**. The exact-image launcher checks these decimal
debug codewords through fixed trusted test-only arguments, renders both payloads,
and verifies their PDF/ZPL embedded pixels. Production options never expose
verbose/debug mode. No invented module-grid vector is claimed for these cases.

Acquisition record: ordinary and explicitly approved download-to-file attempts
for the exact DotCode `.patch` URL both returned:
`Content containing PDF or PS header bytes cannot be rendered from this domain for security reasons.`
This was a content/network-layer response to PowerShell `Invoke-WebRequest`,
not an automatic approval-review rejection. No alternate endpoint, encoding or
transport was used to retrieve that blocked artifact. The local equivalent patch
above was explicitly authorized using the source correction already reviewed.