cmake: dedupe and merge config detection

Before this patch CMake did feature detections in three files:
`src/CMakefiles.txt`, `examples/CMakefiles.txt` and
`tests/CMakefiles.txt`.

Merge and move them to the root `CMakefiles.txt`.

After this patch we end up with a single `src/libssh2_config.h`. This
brings CMake in sync with autotools builds, which already worked with
a single config header.

This also prevents mistakes where feature detection went out of sync
between `src` & `tests` (see ae90a35d15).
`tests` do compile sources from `src` directly, so these should always
be in sync.

It also allows to better integrate hand-crafted, platform-specific
config headers into the builds, like the one currently residing in
the `win32` directory (and also in `vms` and `os400`). Subject to an
upcoming PR.

Also fix a warning revealed after this patch made CMake correctly
enable `HAVE_GETTIMEOFDAY` for `example` programs.

Closes #906

example/CMakeLists.txt

@@ -33,9 +33,12 @@
 # USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
 # OF SUCH DAMAGE.
 
-include(CheckIncludeFiles)
 include(CopyRuntimeDependencies)
 
+list(APPEND LIBRARIES ${SOCKET_LIBRARIES})
+
+add_definitions(-DHAVE_CONFIG_H)
+
 set(EXAMPLES
   direct_tcpip
   ssh2
@@ -61,31 +64,14 @@ set(EXAMPLES
   subsystem_netconf
   tcpip-forward)
 
-list(APPEND LIBRARIES ${SOCKET_LIBRARIES})
-
 foreach(example ${EXAMPLES})
   add_executable(example-${example} ${example}.c)
   list(APPEND EXAMPLE_TARGETS example-${example})
   # to find generated header
-  target_include_directories(example-${example} PRIVATE ${CMAKE_CURRENT_BINARY_DIR})
+  target_include_directories(example-${example} PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/../src)
   target_link_libraries(example-${example} ${LIB_STATIC} ${LIBRARIES})
 endforeach()
 add_target_to_copy_dependencies(
   TARGET copy_example_dependencies
   DEPENDENCIES ${RUNTIME_DEPENDENCIES}
   BEFORE_TARGETS ${EXAMPLE_TARGETS})
-
-## Platform checks
-check_include_files(inttypes.h HAVE_INTTYPES_H)
-check_include_files(unistd.h HAVE_UNISTD_H)
-check_include_files(stdlib.h HAVE_STDLIB_H)
-check_include_files(sys/select.h HAVE_SYS_SELECT_H)
-check_include_files(sys/socket.h HAVE_SYS_SOCKET_H)
-check_include_files(sys/time.h HAVE_SYS_TIME_H)
-check_include_files(arpa/inet.h HAVE_ARPA_INET_H)
-check_include_files(netinet/in.h HAVE_NETINET_IN_H)
-check_include_files(winsock2.h HAVE_WINSOCK2_H)
-
-configure_file(
-  ${CMAKE_CURRENT_SOURCE_DIR}/libssh2_config_cmake.h.in
-  ${CMAKE_CURRENT_BINARY_DIR}/libssh2_config.h)

example/Makefile.am

@@ -1,6 +1,6 @@
 AUTOMAKE_OPTIONS = foreign nostdinc
 
-EXTRA_DIST = libssh2_config_cmake.h.in CMakeLists.txt
+EXTRA_DIST = CMakeLists.txt
 
 # examples
 noinst_PROGRAMS = \

example/libssh2_config_cmake.h.in

@@ -1,46 +0,0 @@
-/* Copyright (c) 2014 Alexander Lamaison <alexander.lamaison@gmail.com>
- *
- * Redistribution and use in source and binary forms,
- * with or without modification, are permitted provided
- * that the following conditions are met:
- *
- *   Redistributions of source code must retain the above
- *   copyright notice, this list of conditions and the
- *   following disclaimer.
- *
- *   Redistributions in binary form must reproduce the above
- *   copyright notice, this list of conditions and the following
- *   disclaimer in the documentation and/or other materials
- *   provided with the distribution.
- *
- *   Neither the name of the copyright holder nor the names
- *   of any other contributors may be used to endorse or
- *   promote products derived from this software without
- *   specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
- * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
- * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
- * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
- * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
- * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
- * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
- * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
- * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
- * OF SUCH DAMAGE.
- */
-
-/* Headers */
-#cmakedefine HAVE_UNISTD_H
-#cmakedefine HAVE_INTTYPES_H
-#cmakedefine HAVE_STDLIB_H
-#cmakedefine HAVE_SYS_SELECT_H
-#cmakedefine HAVE_SYS_SOCKET_H
-#cmakedefine HAVE_SYS_TIME_H
-#cmakedefine HAVE_ARPA_INET_H
-#cmakedefine HAVE_NETINET_IN_H
-#cmakedefine HAVE_WINSOCK2_H

example/scp_nonblock.c

@@ -276,7 +276,8 @@ int main(int argc, char *argv[])
 
     time_ms = tvdiff(end, start);
     fprintf(stderr, "Got %ld bytes in %ld ms = %.1f bytes/sec spin: %d\n",
-            (long)total, time_ms, (double)total/(time_ms/1000.0), spin);
+            (long)total, time_ms,
+            (double)total/((double)time_ms/1000.0), spin);
 #else
     fprintf(stderr, "Got %ld bytes spin: %d\n", (long)total, spin);
 #endif

example/sftp_nonblock.c

@@ -283,7 +283,8 @@ int main(int argc, char *argv[])
     gettimeofday(&end, NULL);
     time_ms = tvdiff(end, start);
     fprintf(stderr, "Got %ld bytes in %ld ms = %.1f bytes/sec spin: %d\n",
-            (long)total, time_ms, (double)total/(time_ms/1000.0), spin);
+            (long)total, time_ms,
+            (double)total/((double)time_ms/1000.0), spin);
 #else
     fprintf(stderr, "Got %ld bytes spin: %d\n", (long)total, spin);
 #endif