From: Daniel Stenberg <daniel@haxx.se>
Date: Fri, 28 Mar 2025 14:37:15 +0000 (+0100)
Subject: docs/internals/PORTING.md: new document
X-Git-Tag: curl-8_13_0~30
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c4863e9d3b0e7cb72751e573fac9fc4a5d31a061;p=thirdparty%2Fcurl.git

docs/internals/PORTING.md: new document

The basic approach I use when porting libcurl to another OS when the
existing configure or cmake build setups are not suitable.

Closes #16860
---

diff --git a/docs/Makefile.am b/docs/Makefile.am
index e0a869bc0c..084d40b798 100644
--- a/docs/Makefile.am
+++ b/docs/Makefile.am
@@ -54,6 +54,7 @@ INTERNALDOCS =                                  \
  internals/MQTT.md                              \
  internals/MULTI-EV.md                          \
  internals/NEW-PROTOCOL.md                      \
+ internals/PORTING.md                           \
  internals/README.md                            \
  internals/SPLAY.md                             \
  internals/STRPARSE.md                          \
diff --git a/docs/internals/PORTING.md b/docs/internals/PORTING.md
new file mode 100644
index 0000000000..aa1aa7873a
--- /dev/null
+++ b/docs/internals/PORTING.md
@@ -0,0 +1,47 @@
+<!--
+Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
+
+SPDX-License-Identifier: curl
+-->
+
+# porting libcurl
+
+The basic approach I use when porting libcurl to another OS when the existing
+configure or cmake build setups are not suitable.
+
+## Build
+
+Write a build script/Makefile that builds *all* C files under lib/. If
+possible, use the `lib/Makefile.inc` that lists all files in Makefile
+variables.
+
+In the Makefile, make sure you define what OS you build for: `-D[OPERATING
+SYSTEM]`, or similar. Perhaps the compiler in use already define a standard
+one? Then you might not need to define your own.
+
+## Add the new OS
+
+In the `lib/curl_config.h` header file, in the section for when `HAVE_CONFIG_H`
+is *not* defined (starting at around line 150), add a new conditional include
+in this style:
+
+~~~c
+#ifdef [OPERATING SYSTEM]
+#  include "config-operatingsystem.h"
+#endif
+~~~
+
+Create `lib/config-operatingsystem.h`. You might want to start with copying a
+another config-* file and then start trimming according to what your
+environment supports.
+
+## Build it
+
+When you run into compiler warnings or errors, the
+`lib/config-operatingsystem.h` file should be where you should focus your work
+and edits.
+
+A recommended approach is to define a lot of the `CURL_DISABLE_*` defines (see
+the [CURL-DISABLE](../CURL-DISABLE.md) document) initially to help narrow down
+the initial work as that can save you from having to give attention to areas of
+the code that you do not care for in your port.