Add the first Conan-based dependecies

add_conan_lib cmake function is defined, that allows to add a dependency using Conan with two possible system fallbacks:

1. pkg_check_modules is invoked, if `PGK_CONFIG ...` is present
2. find_package is invoked if `FIND_PACKAGE_OPTIONS` is present and `pkg_check_modules` has failed

If `ALWAYS_ALLOW_CONAN_FALLBACK` is present - `obey_system_dependencies` will be ignored for the package

Currently, the following dependencies are retrieved using Conan:

* zlib
* expat
* wxwidgets
* libmp3lame
* libid3tag
* libmad

The last three libraries are included in this commit, as they depend on zlib.
Properly pass **arch** and **os.version** to Conan

src/AboutDialog.cpp

@@ -62,7 +62,7 @@ hold information about one contributor to Audacity.
 // RevisionIdent.h may contain #defines like these ones:
 //#define REV_LONG "28864acb238cb3ca71dda190a2d93242591dd80e"
 //#define REV_TIME "Sun Apr 12 12:40:22 2015 +0100"
-#include <RevisionIdent.h>
+#include "RevisionIdent.h"
 
 #ifndef REV_TIME
 #define REV_TIME "unknown date and time"

src/CMakeLists.txt

@@ -21,12 +21,13 @@ if( GIT_FOUND )
    add_custom_target(
       version
       COMMAND
-         ${CMAKE_COMMAND} -D GIT=${GIT_EXECUTABLE}
-                          -D _PRVDIR=${_PRVDIR}
-                          -P ${CMAKE_MODULE_PATH}/Version.cmake
+         ${CMAKE_COMMAND} -D GIT="${GIT_EXECUTABLE}"
+                          -D "_PRVDIR=${_PRVDIR}"
+                          -P "${AUDACITY_MODULE_PATH}/Version.cmake"
       WORKING_DIRECTORY
          ${topdir}
    )
+
    add_dependencies( ${TARGET} version )
 endif()
 
@@ -40,6 +41,17 @@ if( CMAKE_SYSTEM_NAME MATCHES "Darwin" )
    set( USE_AUDIO_UNITS ${${_OPT}use_audio_units} CACHE INTERNAL "" )
 endif()
 
+# Detect, which version of FileDialog to use for
+# We always assume that GTK is used on platforms other than Windows and macOS,
+# as there is no other implementation avalaible now
+if( CMAKE_SYSTEM_NAME MATCHES "Darwin" )
+   set( wxIS_MAC on )
+elseif( CMAKE_SYSTEM_NAME MATCHES "Windows" )
+   set ( wxIS_WIN on )
+else()
+   set ( wxIS_GTK on)
+endif()
+
 # Handle Ladspa option
 cmd_option(
    ${_OPT}use_ladspa
@@ -1054,17 +1066,18 @@ list( APPEND LDFLAGS
 list( APPEND LIBRARIES
    PUBLIC
       ${CMAKE_REQUIRED_LIBRARIES}
-      wxWidgets
-      expat
-      lame
+      ZLIB::ZLIB
+      wxwidgets::wxwidgets
+      expat::expat
+      libmp3lame::libmp3lame
       libsndfile
       libsoxr
       portaudio-v19
       sqlite
       $<$<BOOL:${USE_FFMPEG}>:ffmpeg>
-      $<$<BOOL:${USE_LIBID3TAG}>:libid3tag>
+      $<$<BOOL:${USE_LIBID3TAG}>:libid3tag::libid3tag>
       $<$<BOOL:${USE_LIBFLAC}>:libflac>
-      $<$<BOOL:${USE_LIBMAD}>:libmad>
+      $<$<BOOL:${USE_LIBMAD}>:libmad::libmad>
       $<$<BOOL:${USE_LIBOGG}>:libogg>
       $<$<BOOL:${USE_LIBVORBIS}>:libvorbis>
       $<$<BOOL:${USE_LIBTWOLAME}>:twolame>
@@ -1115,15 +1128,9 @@ if( CMAKE_SYSTEM_NAME MATCHES "Windows" )
    )
 
    # Copy over the wxWidgets DLLs
-   if( ${_OPT}use_wxwidgets STREQUAL "system" )
-      set( wxlibs "$ENV{WXWIN}" )
-   else()
-      set( wxlibs "${CMAKE_BINARY_DIR}" )
-   endif()
 
    # Convert the paths to native
-   file( TO_NATIVE_PATH "${_INTDIR}/dlls" dlls )
-   file( TO_NATIVE_PATH "${wxWidgets_LIB_DIR}" libdir )
+   file( TO_NATIVE_PATH "${CMAKE_BINARY_DIR}/bin/shared" libdir )
    file( TO_NATIVE_PATH "${_EXEDIR}" exedir )
 
    # Copy the required wxWidgets libs into the bundle
@@ -1133,8 +1140,8 @@ if( CMAKE_SYSTEM_NAME MATCHES "Windows" )
       COMMAND
          ${CMAKE_COMMAND} -D SRC="${_EXEDIR}/Audacity.exe"
                           -D DST="${_EXEDIR}"
-                          -D WXWIN="${libdir}"
-                          -P ${CMAKE_MODULE_PATH}/CopyLibs.cmake
+                          -D WXWIN="${libdir}/$<CONFIG>/"
+                          -P ${AUDACITY_MODULE_PATH}/CopyLibs.cmake
       POST_BUILD
    )
 
@@ -1218,7 +1225,8 @@ elseif( CMAKE_SYSTEM_NAME MATCHES "Darwin" )
       COMMAND
          ${CMAKE_COMMAND} -D SRC="${_EXEDIR}/Audacity"
                           -D DST="${_PKGLIB}"
-                          -P ${CMAKE_MODULE_PATH}/CopyLibs.cmake
+                          -D WXWIN="${CMAKE_BINARY_DIR}/lib/shared/$<CONFIG>"
+                          -P ${AUDACITY_MODULE_PATH}/CopyLibs.cmake
       POST_BUILD
    )
 
@@ -1283,8 +1291,8 @@ else()
       COMMAND
          ${CMAKE_COMMAND} -D SRC="${_EXEDIR}/audacity"
                           -D DST="${_DEST}/${_PKGLIB}"
-                          -D WXWIN="${WXWIN}"
-                          -P ${CMAKE_MODULE_PATH}/CopyLibs.cmake
+                          -D WXWIN="${CMAKE_BINARY_DIR}/lib/shared/$<CONFIG>"
+                          -P ${AUDACITY_MODULE_PATH}/CopyLibs.cmake
       POST_BUILD
    )
 endif()