gpg: Minor doc enhancement

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estream: Migrate from Pth to nPth.

--

Actually the mutex stuff was never used since we switched to nPth.
estream: Replace locking macros by functions.

* common/estream.c: Replace most macros.
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The macros were too hard to read and actually blew up the source.
estream: Add debug code to the lock functions.

* common/estream.c (dbg_lock_0, dbg_lock_1, dbg_lock_1): New.
estream: Fix deadlock in es_fileno.

* src/estream.c (es_fileno_unlocked): Call the unlocked functions.
estream: Implement "samethread" mode keyword.

* src/estream.c (estream_internal): Add field SAMETHREAD.
(init_stream_lock, lock_stream, trylock_stream, unlock_stream): Use it.
(parse_mode): Add arg SAMETHREAD and parse that keyword.
(es_initialize): Rename to ...
(init_stream_obj): this.  Add arg SAMETHREAD.
(es_create): Add arg SAMETHREAD.  Call init_stream_lock after
init_stream_obj.
(doreadline): Call es_create with samethread flag.
(es_fopen, es_mopen, es_fopenmem, es_fopencookie, do_fdopen)
(do_fpopen, do_w32open): Implement "samethread" keyword.
(es_freopen): Take samthread flag from old stream.
(es_tmpfile): Call es)_create w/o samethread.
--

Note: Unfortunately es_tmpfile has no mode arg so that we can't use
samethread.
common: Cleanup the use of USE_NPTH and HAVE_NPTH macros.

* configure.ac (HAVE_NPTH): New ac_define.
* common/estream.c: Use USE_NPTH instead of HAVE_NPTH.
* common/http.c: Ditto.  Replace remaining calls to pth by npth calls.
(connect_server): Remove useless _().
* common/exechelp-posix.c, common/exechelp-w32.c
* common/exechelp-w32ce.c: Use HAVE_PTH to include npth.h.
* common/init.c (_init_common_subsystems): Remove call to pth_init.
* common/sysutils.c (gnupg_sleep): Use npth_sleep.
* scd/ccid-driver.c (my_sleep): Ditto.
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USE_NPTH is used in case were we may build with and without nPth.  The
missing definition HAVE_NPTH didn't allowed us to build outher sources
with nPTh support.
http: Revamp TLS API.

* configure.ac (NEED_GNUTLS_VERSION): New.
(HTTP_USE_GNUTLS, LIBGNUTLS_CFLAGS, LIBGNUTLS_LIBS): New ac_subst.

* common/http.h (http_session_t): New.
* common/http.c: Remove compatibility for gnutls < 3.0.
(http_session_s): New.
(cookie_s): Replace gnutls_session_t by http_session_t.
(tls_callback, tls_ca_certlist): New variables.
(my_socket_unref): Add preclose args.
(my_npth_read, my_npth_write): New.
(make_header_line): Fix bug using int* instead of char*.
(http_register_tls_callback): New.
(http_register_tls_ca): New.
(http_session_new): New.
(http_session_release): New.
(http_get_header_names): New.
(escape_data): Add hack to escape in forms mode.
(send_request) [HTTP_USE_GNUTLS]: Support SNI.
(send_request) [HTTP_USE_GNUTLS]: Fix use of make_header_line.
(send_gnutls_bye): New.
(cookie_close): Make use of preclose feature.
(http_verify_server_credentials): New.
(main) [TEST]: Remove test code.
* common/t-http.c: New.
* common/tls-ca.pem: New.
* common/Makefile.am (tls_sources): New. Move http code to here.
(libcommontls_a_SOURCES): New.
(libcommontlsnpth_a_SOURCES): New.
(EXTRA_DIST): Add tls-ca.pem
(module_maint_tests): Add t-http.
(t_http_SOURCES, t_http_CFLAGS, t_http_LDADD): New.

* dirmngr/Makefile.am (dirmngr_LDADD): Add libcommontlsnpth.
--

This new TLS API for http.c is much more flexible than the crude old
hack.
common: Fix test for openpgp_oid_is_ed25519.

* common/t-openpgp-oid.c (test_openpgp_oid_is_ed25519): Add correct
value.