Initial implementation

.github/workflows/ci.yml

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+name: CI
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - "**"
+
+jobs:
+  examples:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: "1.23"
+
+      - name: Regenerate examples
+        run: make -C _examples generate
+
+      - name: Git diff of regenerated files
+        run: make -C _examples diff
+
+  tests:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: "1.23"
+
+      - name: Install native dependencies
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y build-essential pkg-config libcurl4-openssl-dev libcjson-dev
+
+      - name: Run generator tests
+        run: go test ./...

README.md

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+# gen-c
+
+This repo contains the templates used by the `webrpc-gen` CLI to code-generate
+webrpc C client code.
+
+This generator, from a webrpc schema/design file, will code-generate:
+
+1. Header output
+   Public C enums, structs, support types, `init` / `free` helpers, client declarations,
+   and lower-level request / response helpers.
+
+2. Implementation output
+   C JSON encode/decode helpers, generated method request / response handling,
+   and an optional `libcurl`-based client runtime.
+
+The generated client is intended to speak to any webrpc server language
+(Go, nodejs, etc.) as long as the schema features used are supported by this target.
+
+## Dependencies
+
+Generated `header` output only depends on the C standard library headers included by
+the generated file.
+
+Generated `impl` output currently depends on:
+
+- `cJSON`
+- `libcurl`
+
+The generated code targets C99.
+
+Typical compile / link flags look like:
+
+```bash
+cc -std=c99 \
+  $(pkg-config --cflags libcurl libcjson) \
+  -c example.gen.c
+
+cc -std=c99 \
+  app.c example.gen.c \
+  $(pkg-config --cflags --libs libcurl libcjson) \
+  -o app
+```
+
+Dependency names can vary slightly by platform or package manager. The important part
+is that the generated implementation can include `<cjson/cJSON.h>` and link against
+`libcurl` and `cJSON`.
+
+Because the generated implementation uses `cJSON`, exact large 64-bit integer handling
+follows `cJSON`'s numeric behavior. If your API needs exact integer round-tripping beyond
+normal JSON number precision expectations, prefer `bigint` in the schema instead of
+`int64` / `uint64`.
+
+## Features
+
+The current generator supports:
+
+- client code generation
+- separate `header` and `impl` emission
+- generated DTO structs and enums
+- generated `init` / `free` helpers for schema and method wrapper types
+- `bigint` values encoded as JSON strings
+- `timestamp` values encoded as JSON strings
+- `any`, `null`, nested lists, nested maps, and nested structs
+- map keys of type `string` and `enum`
+- succinct method wire format
+- generated lower-level helpers to:
+  - prepare request bytes without sending them
+  - send a prepared request with the generated transport
+  - parse a raw HTTP response into generated response types
+- generated `libcurl` client configuration for bearer auth, custom headers, and timeouts
+
+## Limitations
+
+The current generator does not support:
+
+- server generation
+- streaming methods
+- map keys other than `string` or `enum`
+- a shared external transport abstraction; the generated runtime is currently self-contained
+
+Implementation generation also assumes a companion generated header include via
+`-header=<file>`.
+
+## Usage
+
+Generate the header:
+
+```bash
+webrpc-gen \
+  -schema=example.ridl \
+  -target=./local-gen-c \
+  -emit=header \
+  -out=./example.gen.h
+```
+
+Generate the implementation:
+
+```bash
+webrpc-gen \
+  -schema=example.ridl \
+  -target=./local-gen-c \
+  -emit=impl \
+  -header=example.gen.h \
+  -out=./example.gen.c
+```
+
+When published as a `gen-*` module, this can also be used via:
+
+```bash
+webrpc-gen \
+  -schema=example.ridl \
+  -target=github.com/webrpc/gen-c@<version> \
+  -emit=header \
+  -out=./example.gen.h
+```
+
+or:
+
+```bash
+webrpc-gen \
+  -schema=example.ridl \
+  -target=github.com/webrpc/gen-c@<version> \
+  -emit=impl \
+  -header=example.gen.h \
+  -out=./example.gen.c
+```
+
+## Set Custom Template Variables
+
+Change any of the following values by passing `-option="Value"` CLI flag to `webrpc-gen`.
+
+| webrpc-gen -option | Description | Default value | Version |
+| --- | --- | --- | --- |
+| `-prefix=<name>` | symbol and type prefix | schema name in `snake_case` | v0.0.1 |
+| `-client` | generate client declarations and runtime | `true` | v0.0.1 |
+| `-emit=<mode>` | emit either `header` or `impl` | `header` | v0.0.1 |
+| `-header=<file>` | header include used by `impl` output | `<prefix>.h` | v0.0.1 |
+
+## Notes
+
+- `-target` can be a local template directory or a git module path.
+- `bigint` support is string-based by design to avoid precision loss in C JSON handling.
+- for precision-sensitive large integer values, prefer `bigint` over `int64` / `uint64` in the schema when targeting this generator
+- The generated implementation is tested with smoke, codec, succinct, and reference interop coverage in this repo.

_examples/Makefile

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+WEBRPC_GEN_VERSION := v0.37.1
+ROOT := ..
+GEN := go run -ldflags="-X github.com/webrpc/webrpc.VERSION=$(WEBRPC_GEN_VERSION)" github.com/webrpc/webrpc/cmd/webrpc-gen@$(WEBRPC_GEN_VERSION)
+
+.PHONY: generate diff
+
+generate:
+	$(GEN) -schema=smoke/example.ridl -target=$(ROOT) -emit=header -out=smoke/example.gen.h
+	$(GEN) -schema=smoke/example.ridl -target=$(ROOT) -emit=impl -header=example.gen.h -out=smoke/example.gen.c
+
+diff:
+	git diff --exit-code -- smoke/example.gen.h smoke/example.gen.c