From 136b5879d7d1a382e8b9e61ebc8c1a22082fdef5 Mon Sep 17 00:00:00 2001
From: Patrick Perry <v-patrickpe@microsoft.com>
Date: Fri, 5 Jun 2026 14:37:54 -0700
Subject: [PATCH] Linux: gate WSC source files and zlib system deps on
 HC_NOWEBSOCKETS/HC_NOZLIB

After #965, websocketpp_websocket.cpp was added to LINUX_SOURCE_FILES unconditionally
and install_dependencies.bash installed zlib1g/zlib1g-dev unconditionally. Consumers
opting out via HC_NOWEBSOCKETS or HC_NOZLIB still paid the build/dep cost.

- CMakeLists.txt: gate websocketpp_websocket.{cpp,h} + x509_cert_utilities.hpp on
  NOT DEFINED HC_NOWEBSOCKETS (matches existing HC_NOZLIB gating pattern at line 89).
- install_dependencies.bash: skip zlib1g/zlib1g-dev when HC_NOZLIB=true or
  HC_NOWEBSOCKETS=true (compression cannot run without zlib, and websockets are
  the only consumer of compression).

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
---
 Build/libHttpClient.Linux/CMakeLists.txt            | 11 ++++++++---
 Build/libHttpClient.Linux/install_dependencies.bash |  9 ++++++++-
 2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/Build/libHttpClient.Linux/CMakeLists.txt b/Build/libHttpClient.Linux/CMakeLists.txt
index 87622d76..7d298ecb 100644
--- a/Build/libHttpClient.Linux/CMakeLists.txt
+++ b/Build/libHttpClient.Linux/CMakeLists.txt
@@ -81,11 +81,16 @@ set(LINUX_SOURCE_FILES
     "${PATH_TO_ROOT}/Source/Platform/Linux/PlatformComponents_Linux.cpp"
     "${PATH_TO_ROOT}/Source/Task/ThreadPool_stl.cpp"
     "${PATH_TO_ROOT}/Source/Task/WaitTimer_stl.cpp"
-    "${PATH_TO_ROOT}/Source/WebSocket/Websocketpp/websocketpp_websocket.cpp"
-    "${PATH_TO_ROOT}/Source/WebSocket/Websocketpp/websocketpp_websocket.h"
-    "${PATH_TO_ROOT}/Source/WebSocket/Websocketpp/x509_cert_utilities.hpp"
     )
 
+if (NOT DEFINED HC_NOWEBSOCKETS)
+    list(APPEND LINUX_SOURCE_FILES
+        "${PATH_TO_ROOT}/Source/WebSocket/Websocketpp/websocketpp_websocket.cpp"
+        "${PATH_TO_ROOT}/Source/WebSocket/Websocketpp/websocketpp_websocket.h"
+        "${PATH_TO_ROOT}/Source/WebSocket/Websocketpp/x509_cert_utilities.hpp"
+    )
+endif()
+
 if (NOT DEFINED HC_NOZLIB)
     set(ZLIB_SOURCE_FILES
        "${PATH_TO_ROOT}/External/zlib/adler32.c"
diff --git a/Build/libHttpClient.Linux/install_dependencies.bash b/Build/libHttpClient.Linux/install_dependencies.bash
index 1b85ec62..377ed5f8 100755
--- a/Build/libHttpClient.Linux/install_dependencies.bash
+++ b/Build/libHttpClient.Linux/install_dependencies.bash
@@ -26,7 +26,14 @@ done
 set -- "${POSITIONAL_ARGS[@]}" # restore positional parameters
 
 build_dependencies=(clang make autoconf automake libtool)
-library_dependencies=(zlib1g zlib1g-dev)
+library_dependencies=()
+
+# zlib is only needed when zlib support is enabled (default on) AND websockets are enabled,
+# since WebSocket Compression (HC_ENABLE_WEBSOCKET_COMPRESSION, default ON) depends on zlib.
+# Consumers that opt out via HC_NOZLIB=true or HC_NOWEBSOCKETS=true do not need zlib system packages.
+if [ "${HC_NOZLIB}" != "true" ] && [ "${HC_NOWEBSOCKETS}" != "true" ]; then
+  library_dependencies+=(zlib1g zlib1g-dev)
+fi
 
 if [ "$DO_INSTALL" = false ]; then