From 88a8ef949c315b2023c4476589fd4e4fb1169b28 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=89rico=20Nogueira?= <erico.erc@gmail.com>
Date: Fri, 18 Jun 2021 12:48:40 -0300
Subject: [PATCH] Remove OpenSSL locking from kicad_curl.

It's fair to assume all libcurl versions in circulation will already be
using OpenSSL>=1.1.0. This code is also unnecessary on platforms that
use other libcurl SSL backends, such as Debian's libcurl-gnutls package.
---
 common/CMakeLists.txt            |   6 --
 common/kicad_curl/kicad_curl.cpp | 104 -------------------------------
 2 files changed, 110 deletions(-)

diff --git a/common/CMakeLists.txt b/common/CMakeLists.txt
index 3498d28c32..3b3fbe7ced 100644
--- a/common/CMakeLists.txt
+++ b/common/CMakeLists.txt
@@ -19,11 +19,6 @@ include_directories(
     ${INC_AFTER}
     )
 
-if( NOT APPLE )     # windows and linux use openssl under curl
-    find_package( OpenSSL REQUIRED )
-    include_directories( SYSTEM ${OPENSSL_INCLUDE_DIR} )
-endif()
-
 set( GAL_SRCS
     # Common part
     basic_gal.cpp
@@ -489,7 +484,6 @@ target_link_libraries( common
     pybind11::embed
     ${Boost_LIBRARIES}
     ${CURL_LIBRARIES}
-    ${OPENSSL_LIBRARIES}        # empty on Apple
     ${wxWidgets_LIBRARIES}
     ${EXTRA_LIBS}
     )
diff --git a/common/kicad_curl/kicad_curl.cpp b/common/kicad_curl/kicad_curl.cpp
index a1131d9837..5cc2843ce6 100644
--- a/common/kicad_curl/kicad_curl.cpp
+++ b/common/kicad_curl/kicad_curl.cpp
@@ -39,106 +39,6 @@ static volatile bool s_initialized;
 
 static std::mutex s_lock;        // for s_initialized
 
-// Assume that on these platforms libcurl uses OpenSSL
-#if defined(__linux__) || defined(__MINGW32__)
-
-#include <openssl/crypto.h>
-
-static std::mutex* s_crypto_locks;
-
-/*
- * From OpenSSL v1.1.0, the CRYPTO_set_locking_callback macro is a no-op.
- *
- * Once this is the minimum OpenSSL version, the entire s_crypto_locks
- * system and related functions can be removed.
- *
- * In the meantime, use this macro to determine when to use the callback.
- * Keep them compiling until then to prevent accidentally breaking older
- * version builds.
- *
- * https://github.com/openssl/openssl/issues/1260
- */
-#if OPENSSL_VERSION_NUMBER < 0x10100000L
-#define USE_OPENSSL_LOCKING_CALLBACKS
-#endif
-
-
-static void lock_callback( int mode, int type, const char* file, int line )
-{
-    (void)file;
-    (void)line;
-
-    wxASSERT( s_crypto_locks && unsigned( type ) < unsigned( CRYPTO_num_locks() ) );
-
-    if( mode & CRYPTO_LOCK )
-    {
-        s_crypto_locks[ type ].lock();
-    }
-    else
-    {
-        s_crypto_locks[ type ].unlock();
-    }
-}
-
-
-static void init_locks()
-{
-    s_crypto_locks = new std::mutex[ CRYPTO_num_locks() ];
-
-    // From http://linux.die.net/man/3/crypto_set_id_callback:
-
-    /*
-
-    OpenSSL can safely be used in multi-threaded applications provided that at
-    least two callback functions are set, locking_function and threadid_func.
-
-    locking_function(int mode, int n, const char *file, int line) is needed to
-    perform locking on shared data structures. (Note that OpenSSL uses a number
-    of global data structures that will be implicitly shared whenever multiple
-    threads use OpenSSL.) Multi-threaded applications will crash at random if it
-    is not set.
-
-    threadid_func( CRYPTO_THREADID *id) is needed to record the
-    currently-executing thread's identifier into id. The implementation of this
-    callback should not fill in id directly, but should use
-    CRYPTO_THREADID_set_numeric() if thread IDs are numeric, or
-    CRYPTO_THREADID_set_pointer() if they are pointer-based. If the application
-    does not register such a callback using CRYPTO_THREADID_set_callback(), then
-    a default implementation is used - on Windows and BeOS this uses the
-    system's default thread identifying APIs, and on all other platforms it uses
-    the address of errno. The latter is satisfactory for thread-safety if and
-    only if the platform has a thread-local error number facility.
-
-    Dick: "sounds like CRYPTO_THREADID_set_callback() is not mandatory on our
-    2 OpenSSL platforms."
-
-    */
-
-    CRYPTO_set_locking_callback( &lock_callback );
-
-#ifndef USE_OPENSSL_LOCKING_CALLBACKS
-    // Ignore the unused function (the above macro didn't use it)
-    (void) &lock_callback;
-#endif
-}
-
-
-static void kill_locks()
-{
-    CRYPTO_set_locking_callback( NULL );
-
-    delete[] s_crypto_locks;
-
-    s_crypto_locks = NULL;
-}
-
-#else
-
-inline void init_locks()    { /* dummy */ }
-inline void kill_locks()    { /* dummy */ }
-
-#endif
-
 /// At process termination, using atexit() keeps the CURL stuff out of the
 /// singletops and PGM_BASE.
 static void at_terminate()
@@ -163,8 +63,6 @@ void KICAD_CURL::Init()
                 THROW_IO_ERROR( "curl_global_init() failed." );
             }
 
-            init_locks();
-
             s_initialized = true;
         }
     }
@@ -196,8 +94,6 @@ void KICAD_CURL::Cleanup()
         {
             curl_global_cleanup();
 
-            kill_locks();
-
             atexit( &at_terminate );
 
             s_initialized = false;