Use longjmp at setjmp where possible

Where we can we should use longjmp and setjmp in preference to swapcontext/
setcontext as they seem to be more performant.
Reviewed-by: NRich Salz <rsalz@openssl.org>

crypto/async/Makefile

@@ -77,7 +77,7 @@ clean:
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-arch/async_posix.o: ../../include/openssl/async.h
+arch/async_posix.o: ../../e_os.h ../../include/openssl/async.h
 arch/async_posix.o: ../../include/openssl/crypto.h
 arch/async_posix.o: ../../include/openssl/e_os2.h
 arch/async_posix.o: ../../include/openssl/opensslconf.h
@@ -90,9 +90,10 @@ arch/async_posix.o: arch/../arch/async_posix.h arch/../arch/async_win.h
 arch/async_posix.o: arch/../async_locl.h arch/async_posix.c
 arch/async_win.o: ../../include/openssl/async.h arch/async_win.c
 arch/async_win.o: arch/async_win.h
-async.o: ../../include/openssl/async.h ../../include/openssl/crypto.h
-async.o: ../../include/openssl/e_os2.h ../../include/openssl/opensslconf.h
-async.o: ../../include/openssl/opensslv.h ../../include/openssl/ossl_typ.h
-async.o: ../../include/openssl/safestack.h ../../include/openssl/stack.h
-async.o: ../../include/openssl/symhacks.h arch/async_null.h arch/async_posix.h
-async.o: arch/async_win.h async.c async_locl.h
+async.o: ../../e_os.h ../../include/openssl/async.h
+async.o: ../../include/openssl/crypto.h ../../include/openssl/e_os2.h
+async.o: ../../include/openssl/opensslconf.h ../../include/openssl/opensslv.h
+async.o: ../../include/openssl/ossl_typ.h ../../include/openssl/safestack.h
+async.o: ../../include/openssl/stack.h ../../include/openssl/symhacks.h
+async.o: arch/async_null.h arch/async_posix.h arch/async_win.h async.c
+async.o: async_locl.h

crypto/async/arch/async_posix.c

@@ -75,6 +75,7 @@ int ASYNC_FIBRE_init(ASYNC_FIBRE *fibre)
     fibre->fibre.uc_stack.ss_sp = stack;
     fibre->fibre.uc_stack.ss_size = STACKSIZE;
     fibre->fibre.uc_link = NULL;
+    fibre->env_init = 0;
 
     return 1;
 }

crypto/async/arch/async_posix.h

@@ -62,20 +62,34 @@
 #  define ASYNC_ARCH
 
 #  include <ucontext.h>
+#  include <setjmp.h>
+#  include "e_os.h"
 
 extern __thread ASYNC_CTX *sysvctx;
 
 typedef struct async_fibre_st {
     ucontext_t fibre;
+    jmp_buf env;
+    int env_init;
 } ASYNC_FIBRE;
 
 #  define ASYNC_set_ctx(nctx)             (sysvctx = (nctx))
 #  define ASYNC_get_ctx()                 (sysvctx)
-#  define ASYNC_FIBRE_swapcontext(o,n,r) \
-            ((r)? \
-                !swapcontext(&(o)->fibre, &(n)->fibre) \
-            : \
-                !setcontext(&(n)->fibre))
+
+static inline int ASYNC_FIBRE_swapcontext(ASYNC_FIBRE *o, ASYNC_FIBRE *n, int r)
+{
+    o->env_init = 1;
+
+    if (!r || !setjmp(o->env)) {
+        if (n->env_init)
+            longjmp(n->env, 1);
+        else
+            setcontext(&n->fibre);
+    }
+
+    return 1;
+}
+
 #  define ASYNC_FIBRE_makecontext(c) \
             (ASYNC_FIBRE_init(c) \
             && !getcontext(&(c)->fibre) \

util/libeay.num

@@ -4651,6 +4651,6 @@ TS_RESP_CTX_set_signer_digest           5010	EXIST::FUNCTION:
 TS_CONF_set_signer_digest               5011	EXIST::FUNCTION:
 ENGINE_load_dasync                      5012	EXIST::FUNCTION:ENGINE,STATIC_ENGINE
 ASYNC_pause_job                         5013	EXIST::FUNCTION:
-ASYNC_job_is_waiting                    5014	EXIST::FUNCTION:
+ASYNC_job_is_waiting                    5014	NOEXIST::FUNCTION:
 ASYNC_in_job                            5015	EXIST::FUNCTION:
 ASYNC_start_job                         5016	EXIST::FUNCTION: