CMake: Search for asciidoctor-pdf separate from asciidoctor.

Search for asciidoctorj and asciidoctor-pdf and set
ASCIIDOCTOR_PDF_EXECUTABLE if either are found. Only enable the PDF
targets if we find ASCIIDOCTOR_PDF_EXECUTABLE.

Remove env.cmake since it's no longer needed.

Change-Id: Iee82b30eaa67d1ad3fd3a296d9997b0643a0cb4e
Reviewed-on: https://code.wireshark.org/review/27696
Reviewed-by: Gerald Combs <gerald@wireshark.org>
Petri-Dish: Gerald Combs <gerald@wireshark.org>
Tested-by: Petri Dish Buildbot
Reviewed-by: Anders Broman <a.broman58@gmail.com>

2 files changed, 46 insertions, 101 deletions

diff --git a/cmake/env.cmake b/cmake/env.cmake
deleted file mode 100644
index 677c94c4f9..0000000000
--- a/cmake/env.cmake
+++ /dev/null
@@ -1,76 +0,0 @@
-#
-# Set environment variables and execute a program.
-# Attempts to emulate "cmake -E env" which is only available since CMake 3.1.
-#
-# Copyright 2018 Peter Wu <peter@lekensteyn.nl>
-# SPDX-License-Identifier: MIT
-#
-# Usage:
-#
-#   cmake -P env.cmake [NAME=VALUE]... [COMMAND [ARG]...]
-#
-# Limitations due to CMake:
-#
-# - The command and arguments cannot be keywords for the "execute_process"
-#   command ("COMMAND", "ENCODING", "TIMEOUT", "WORKING_DIRECTORY", etc.).
-# - Empty arguments are ignored, arguments with a trailing backslash ("\") will
-#   have the slash replaced by a forward slash ("/").
-# - If a program fails, a message will be printed and exit code 1 is returned.
-
-# Choose between two evils for the command line limitations:
-# (1) Hard-coded number of maximum arguments and repetitive lines.
-# (2) Limitations on the arguments (due to use of lists).
-# (3) A combination of both.
-# For simplicity, (2) is chosen here.
-set(command)
-
-math(EXPR argsCount "${CMAKE_ARGC} - 1")
-set(skip_args ${argsCount})
-set(maybe_env TRUE)
-
-foreach(argNumber RANGE ${argsCount})
-  set(arg "${CMAKE_ARGV${argNumber}}")
-
-  if(skip_args EQUAL 0)
-    # Escape ";" (list separator) to avoid splitting arguments.
-    string(REPLACE ";" "\\;" argForList "${arg}")
-
-    # Prevent a trailing backslash from escaping the next list separator.
-    # Hopefully it is just a path separator, otherwise there will be problems.
-    if(argForList MATCHES "(.*)\\\\$")
-      message(WARNING "Trailing backslash is converted to forward slash in: ${arg}")
-      set(argForList "${CMAKE_MATCH_1}/")
-    endif()
-
-    if(argForList STREQUAL "")
-      message(WARNING "Empty arguments are currently not supported and ignored")
-    endif()
-
-    if(maybe_env)
-      # Try to parse NAME=VALUE
-      if(arg MATCHES "^([^=]+)=(.*)$")
-        set("ENV{${CMAKE_MATCH_1}}" "${CMAKE_MATCH_2}")
-      else()
-        set(maybe_env FALSE)
-        list(APPEND command "${argForList}")
-      endif()
-    else()
-      # Definitely no more env vars.
-      list(APPEND command "${argForList}")
-    endif()
-  else()
-    # Skip arguments until "-P env.cmake" is found.
-    if(arg STREQUAL "-P")
-      # just skip "env.cmake" from now on
-      set(skip_args 1)
-    else()
-      math(EXPR skip_args "${skip_args} - 1")
-    endif()
-  endif()
-endforeach()
-
-execute_process(COMMAND ${command} RESULT_VARIABLE exitCode)
-
-if(NOT exitCode EQUAL 0)
-  message(FATAL_ERROR "Process exited with ${exitCode}")
-endif()
diff --git a/cmake/modules/FindAsciidoctor.cmake b/cmake/modules/FindAsciidoctor.cmake
index f6328876d3..cdbb351311 100644
--- a/cmake/modules/FindAsciidoctor.cmake
+++ b/cmake/modules/FindAsciidoctor.cmake
@@ -19,6 +19,18 @@ FIND_PROGRAM(ASCIIDOCTOR_EXECUTABLE
     DOC "Path to Asciidoctor or AsciidoctorJ"
 )
 
+FIND_PROGRAM(ASCIIDOCTOR_PDF_EXECUTABLE
+    NAMES
+        asciidoctorj
+        asciidoctor-pdf
+    PATHS
+        /bin
+        /usr/bin
+        /usr/local/bin
+        ${CHOCOLATEY_BIN_PATH}
+    DOC "Path to Asciidoctor or AsciidoctorJ"
+)
+
 if(ASCIIDOCTOR_EXECUTABLE)
     # The AsciidctorJ wrapper script sets -Xmx256m. This isn't enough
     # for the User's Guide.
@@ -42,14 +54,8 @@ if(ASCIIDOCTOR_EXECUTABLE)
         --require ${CMAKE_CURRENT_SOURCE_DIR}/asciidoctor-macros/ws_salink-inline-macro.rb
     )
 
-    if(CMAKE_VERSION VERSION_LESS 3.1)
-        set(_env_command ${CMAKE_COMMAND} -P ${CMAKE_SOURCE_DIR}/cmake/env.cmake)
-    else()
-        set(_env_command ${CMAKE_COMMAND} -E env)
-    endif()
-
-    set(_asciidoctor_common_command ${_env_command}
-        TZ=UTC ASCIIDOCTORJ_OPTS="${_asciidoctorj_opts}"
+    set(_asciidoctor_common_command
+        ${CMAKE_COMMAND} -E env TZ=UTC ASCIIDOCTORJ_OPTS="${_asciidoctorj_opts}"
         ${ASCIIDOCTOR_EXECUTABLE}
         ${_asciidoctor_common_args}
     )
@@ -118,26 +124,41 @@ if(ASCIIDOCTOR_EXECUTABLE)
     # news: release-notes.txt
     #         ${CMAKE_COMMAND} -E copy_if_different release-notes.txt ../NEWS
 
-    MACRO( ASCIIDOCTOR2PDF _asciidocsource )
-        GET_FILENAME_COMPONENT( _source_base_name ${_asciidocsource} NAME_WE )
-        set( _output_pdf ${_source_base_name}.pdf )
+    if(ASCIIDOCTOR_PDF_EXECUTABLE)
 
-        ADD_CUSTOM_COMMAND(
+        set(_asciidoctor_pdf_common_command
+            ${CMAKE_COMMAND} -E env TZ=UTC ASCIIDOCTORJ_OPTS="${_asciidoctorj_opts}"
+            ${ASCIIDOCTOR_PDF_EXECUTABLE}
+            --require asciidoctor-pdf
+            --backend pdf
+            ${_asciidoctor_common_args}
+        )
+
+        MACRO( ASCIIDOCTOR2PDF _asciidocsource )
+            GET_FILENAME_COMPONENT( _source_base_name ${_asciidocsource} NAME_WE )
+            set( _output_pdf ${_source_base_name}.pdf )
+
+            ADD_CUSTOM_COMMAND(
             OUTPUT
-                ${_output_pdf}
-            COMMAND ${_asciidoctor_common_command}
-                --backend pdf
-                ${_asciidoctor_common_args}
-                --out-file ${_output_pdf}
-                ${CMAKE_CURRENT_SOURCE_DIR}/${_asciidocsource}
+                    ${_output_pdf}
+            COMMAND ${_asciidoctor_pdf_common_command}
+                    --out-file ${_output_pdf}
+                    ${CMAKE_CURRENT_SOURCE_DIR}/${_asciidocsource}
             DEPENDS
-                ${CMAKE_CURRENT_SOURCE_DIR}/${_asciidocsource}
-                ${ARGN}
-        )
-        add_custom_target(generate_${_output_pdf} DEPENDS ${_output_pdf})
-        set_asciidoctor_target_properties(generate_${_output_pdf})
-        unset(_output_pdf)
-    ENDMACRO()
+                    ${CMAKE_CURRENT_SOURCE_DIR}/${_asciidocsource}
+                    ${ARGN}
+            )
+            add_custom_target(generate_${_output_pdf} DEPENDS ${_output_pdf})
+            set_asciidoctor_target_properties(generate_${_output_pdf})
+            unset(_output_pdf)
+        ENDMACRO()
+
+    else(ASCIIDOCTOR_PDF_EXECUTABLE)
+
+        MACRO( ASCIIDOCTOR2PDF _asciidocsource )
+        ENDMACRO()
+
+    endif(ASCIIDOCTOR_PDF_EXECUTABLE)
 
 endif(ASCIIDOCTOR_EXECUTABLE)