mirror of
https://github.com/microsoft/vcpkg.git
synced 2024-12-19 00:57:50 +08:00
fe2a6bb789
This contains all the docs and scripts changes from #16479, without any of the ports changes, for easier CR
60 lines
2.7 KiB
Markdown
60 lines
2.7 KiB
Markdown
# Host Dependencies
|
|
|
|
Tools used at build time by other ports to generate code or implement a custom build system can be packaged inside vcpkg.
|
|
|
|
## Consuming
|
|
|
|
When consuming a port as a tool, you must set the dependency's `"host"` field to true. For example:
|
|
```json
|
|
{
|
|
"name": "contoso-http-library",
|
|
"version-string": "1.0.0",
|
|
"description": "Contoso's http runtime library",
|
|
"dependencies": [
|
|
"contoso-core-library",
|
|
{
|
|
"name": "contoso-code-generator",
|
|
"host": true
|
|
},
|
|
{
|
|
"name": "contoso-build-system",
|
|
"host": true
|
|
}
|
|
]
|
|
}
|
|
```
|
|
In this case, the `contoso-code-generator` and `contoso-build-system` (including any transitive dependencies) will be built and installed for the host triplet before `contoso-http-library` is built.
|
|
|
|
>Note: Consumers must use `vcpkg.json` instead of `CONTROL` as their metadata format. You can easily convert an existing `CONTROL` file using `vcpkg format-manifest /path/to/CONTROL`.
|
|
|
|
Then, within the portfile of the consumer (`contoso-http-library` in the example), the CMake variable `CURRENT_HOST_INSTALLED_DIR` will be defined to `installed/<host-triplet>` and should be used to locate any required assets. In the example, `contoso-code-generator` might have installed `tools/contoso-code-generator/ccg.exe` which the consumer would add to its local path via
|
|
```cmake
|
|
# ports/contoso-http-library/portfile.cmake
|
|
vcpkg_add_to_path(${CURRENT_HOST_INSTALLED_DIR}/tools/contoso-code-generator)
|
|
```
|
|
|
|
## Specifying the Host Triplet
|
|
|
|
The default host triplets are chosen based on the host architecture and operating system, for example `x64-windows`, `x64-linux`, or `x64-osx`. They can be overridden via:
|
|
|
|
1. In CMake-based manifest mode, calling `set(VCPKG_HOST_TRIPLET "<triplet>" CACHE STRING "")` before the first `project()` directive
|
|
2. In MSBuild-based manifest mode, setting the `VcpkgHostTriplet` property
|
|
3. On the command line, via the flag `--host-triplet=...`
|
|
4. The `VCPKG_DEFAULT_HOST_TRIPLET` environment variable
|
|
|
|
## Producing
|
|
|
|
Producing a tool has no special requirements; tools should be authored as a standard port, following all the normal policies and practices. Notably, they should build against `TARGET_TRIPLET`, not `HOST_TRIPLET` within the context of their portfile.
|
|
|
|
Sometimes, it can be useful to determine whether the current context is a cross-compiling one or not. This should be done by comparing the strings `TARGET_TRIPLET` and `HOST_TRIPLET`. For example:
|
|
|
|
```cmake
|
|
string(COMPARE EQUAL "${TARGET_TRIPLET}" "${HOST_TRIPLET}" I_AM_NOT_CROSSCOMPILING)
|
|
|
|
if(TARGET_TRIPLET STREQUAL HOST_TRIPLET)
|
|
# This is a native build
|
|
else()
|
|
# This is a cross build
|
|
endif()
|
|
```
|