summaryrefslogtreecommitdiffstats
path: root/Modules/ExternalData.cmake
diff options
context:
space:
mode:
authorBrad King <brad.king@kitware.com>2013-01-24 18:29:48 (GMT)
committerBrad King <brad.king@kitware.com>2013-01-24 18:32:17 (GMT)
commitab26249db107146fc9ad624ac9dddc4052e798d6 (patch)
treede6903f12cd6c799f1f3f6f0d2b13b34a601548f /Modules/ExternalData.cmake
parent21fc6c46df7f2271d7baace04f239f031785b917 (diff)
downloadCMake-ab26249db107146fc9ad624ac9dddc4052e798d6.zip
CMake-ab26249db107146fc9ad624ac9dddc4052e798d6.tar.gz
CMake-ab26249db107146fc9ad624ac9dddc4052e798d6.tar.bz2
Add ExternalData module
Take files we previously distributed in ITK 4.3.1: CMake/ExternalData.cmake CMake/ExternalData_config.cmake.in and add them for distribution in upstream CMake. Update the copyright notice block format to follow CMake conventions.
Diffstat (limited to 'Modules/ExternalData.cmake')
-rw-r--r--Modules/ExternalData.cmake710
1 files changed, 710 insertions, 0 deletions
diff --git a/Modules/ExternalData.cmake b/Modules/ExternalData.cmake
new file mode 100644
index 0000000..84020f9
--- /dev/null
+++ b/Modules/ExternalData.cmake
@@ -0,0 +1,710 @@
+# - Manage data files stored outside source tree
+# Use this module to unambiguously reference data files stored outside the
+# source tree and fetch them at build time from arbitrary local and remote
+# content-addressed locations. Functions provided by this module recognize
+# arguments with the syntax "DATA{<name>}" as references to external data,
+# replace them with full paths to local copies of those data, and create build
+# rules to fetch and update the local copies.
+#
+# The DATA{} syntax is literal and the <name> is a full or relative path
+# within the source tree. The source tree must contain either a real data
+# file at <name> or a "content link" at <name><ext> containing a hash of the
+# real file using a hash algorithm corresponding to <ext>. For example, the
+# argument "DATA{img.png}" may be satisfied by either a real "img.png" file in
+# the current source directory or a "img.png.md5" file containing its MD5 sum.
+#
+# The 'ExternalData_Expand_Arguments' function evaluates DATA{} references
+# in its arguments and constructs a new list of arguments:
+# ExternalData_Expand_Arguments(
+# <target> # Name of data management target
+# <outVar> # Output variable
+# [args...] # Input arguments, DATA{} allowed
+# )
+# It replaces each DATA{} reference in an argument with the full path of a
+# real data file on disk that will exist after the <target> builds.
+#
+# The 'ExternalData_Add_Test' function wraps around the CMake add_test()
+# command but supports DATA{} references in its arguments:
+# ExternalData_Add_Test(
+# <target> # Name of data management target
+# ... # Arguments of add_test(), DATA{} allowed
+# )
+# It passes its arguments through ExternalData_Expand_Arguments and then
+# invokes add_test() using the results.
+#
+# The 'ExternalData_Add_Target' function creates a custom target to manage
+# local instances of data files stored externally:
+# ExternalData_Add_Target(
+# <target> # Name of data management target
+# )
+# It creates custom commands in the target as necessary to make data files
+# available for each DATA{} reference previously evaluated by other functions
+# provided by this module. A list of URL templates must be provided in the
+# variable ExternalData_URL_TEMPLATES using the placeholders "%(algo)" and
+# "%(hash)" in each template. Data fetch rules try each URL template in order
+# by substituting the hash algorithm name for "%(algo)" and the hash value for
+# "%(hash)".
+#
+# The following hash algorithms are supported:
+# %(algo) <ext> Description
+# ------- ----- -----------
+# MD5 .md5 Message-Digest Algorithm 5, RFC 1321
+# Note that the hashes are used only for unique data identification and
+# download verification. This is not security software.
+#
+# Example usage:
+# include(ExternalData)
+# set(ExternalData_URL_TEMPLATES "file:///local/%(algo)/%(hash)"
+# "http://data.org/%(algo)/%(hash)")
+# ExternalData_Add_Test(MyData
+# NAME MyTest
+# COMMAND MyExe DATA{MyInput.png}
+# )
+# ExternalData_Add_Target(MyData)
+# When test "MyTest" runs the "DATA{MyInput.png}" argument will be replaced by
+# the full path to a real instance of the data file "MyInput.png" on disk. If
+# the source tree contains a content link such as "MyInput.png.md5" then the
+# "MyData" target creates a real "MyInput.png" in the build tree.
+#
+# The DATA{} syntax can automatically recognize and fetch a file series. If
+# the source tree contains a group of files or content links named like a
+# series then a DATA{} reference to one member adds rules to fetch all of
+# them. Although all members of a series are fetched, only the file
+# originally named by the DATA{} argument is substituted for it. Two
+# variables configure recognition of a series from DATA{<name>}. First,
+# ExternalData_SERIES_PARSE is a regex of the form "^(...)(...)(...)$" to
+# parse <prefix>, <number>, and <suffix> parts from <name>. Second,
+# ExternalData_SERIES_MATCH is a regex matching the <number> part of series
+# members named <prefix><number><suffix>. Note that the <suffix> of a series
+# does not include a hash-algorithm extension. Both series configuration
+# variables have default values that work well for common cases.
+#
+# The DATA{} syntax can alternatively match files associated with the named
+# file and contained in the same directory. Associated files may be specified
+# by options using the syntax DATA{<name>,<opt1>,<opt2>,...}. Each option may
+# specify one file by name or specify a regular expression to match file names
+# using the syntax REGEX:<regex>. For example, the arguments
+# DATA{MyData/MyInput.mhd,MyInput.img} # File pair
+# DATA{MyData/MyFrames00.png,REGEX:MyFrames[0-9]+\\.png} # Series
+# will pass MyInput.mha and MyFrames00.png on the command line but ensure
+# that the associated files are present next to them.
+#
+# The variable ExternalData_LINK_CONTENT may be set to the name of a supported
+# hash algorithm to enable automatic conversion of real data files referenced
+# by the DATA{} syntax into content links. For each such <file> a content
+# link named "<file><ext>" is created. The original file is renamed to the
+# form ".ExternalData_<algo>_<hash>" to stage it for future transmission to
+# one of the locations in the list of URL templates (by means outside the
+# scope of this module). The data fetch rule created for the content link
+# will use the staged object if it cannot be found using any URL template.
+#
+# The variable ExternalData_OBJECT_STORES may be set to a list of local
+# directories that store objects using the layout <dir>/%(algo)/%(hash).
+# These directories will be searched first for a needed object. If the object
+# is not available in any store then it will be fetched remotely using the URL
+# templates and added to the first local store listed. If no stores are
+# specified the default is a location inside the build tree.
+#
+# The variable ExternalData_SOURCE_ROOT may be set to the highest source
+# directory containing any path named by a DATA{} reference. The default is
+# CMAKE_SOURCE_DIR. ExternalData_SOURCE_ROOT and CMAKE_SOURCE_DIR must refer
+# to directories within a single source distribution (e.g. they come together
+# in one tarball).
+#
+# The variable ExternalData_BINARY_ROOT may be set to the directory to hold
+# the real data files named by expanded DATA{} references. The default is
+# CMAKE_BINARY_DIR. The directory layout will mirror that of content links
+# under ExternalData_SOURCE_ROOT.
+#
+# Variables ExternalData_TIMEOUT_INACTIVITY and ExternalData_TIMEOUT_ABSOLUTE
+# set the download inactivity and absolute timeouts, in seconds. The defaults
+# are 60 seconds and 300 seconds, respectively. Set either timeout to 0
+# seconds to disable enforcement. The inactivity timeout is enforced only
+# with CMake >= 2.8.5.
+
+#=============================================================================
+# Copyright 2010-2013 Kitware, Inc.
+#
+# Distributed under the OSI-approved BSD License (the "License");
+# see accompanying file Copyright.txt for details.
+#
+# This software is distributed WITHOUT ANY WARRANTY; without even the
+# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+# See the License for more information.
+#=============================================================================
+# (To distribute this file outside of CMake, substitute the full
+# License text for the above reference.)
+
+function(ExternalData_add_test target)
+ ExternalData_expand_arguments("${target}" testArgs ${ARGN})
+ add_test(${testArgs})
+endfunction()
+
+function(ExternalData_add_target target)
+ if(NOT ExternalData_URL_TEMPLATES)
+ message(FATAL_ERROR "ExternalData_URL_TEMPLATES is not set!")
+ endif()
+ if(NOT ExternalData_OBJECT_STORES)
+ set(ExternalData_OBJECT_STORES ${CMAKE_BINARY_DIR}/ExternalData/Objects)
+ endif()
+ set(config ${CMAKE_CURRENT_BINARY_DIR}/${target}_config.cmake)
+ configure_file(${_ExternalData_SELF_DIR}/ExternalData_config.cmake.in ${config} @ONLY)
+
+ set(files "")
+
+ # Set "_ExternalData_FILE_${file}" for each output file to avoid duplicate
+ # rules. Use local data first to prefer real files over content links.
+
+ # Custom commands to copy or link local data.
+ get_property(data_local GLOBAL PROPERTY _ExternalData_${target}_LOCAL)
+ foreach(entry IN LISTS data_local)
+ string(REPLACE "|" ";" tuple "${entry}")
+ list(GET tuple 0 file)
+ list(GET tuple 1 name)
+ if(NOT DEFINED "_ExternalData_FILE_${file}")
+ set("_ExternalData_FILE_${file}" 1)
+ add_custom_command(
+ COMMENT "Generating ${file}"
+ OUTPUT "${file}"
+ COMMAND ${CMAKE_COMMAND} -Drelative_top=${CMAKE_BINARY_DIR}
+ -Dfile=${file} -Dname=${name}
+ -DExternalData_ACTION=local
+ -DExternalData_CONFIG=${config}
+ -P ${_ExternalData_SELF}
+ DEPENDS "${name}"
+ )
+ list(APPEND files "${file}")
+ endif()
+ endforeach()
+
+ # Custom commands to fetch remote data.
+ get_property(data_fetch GLOBAL PROPERTY _ExternalData_${target}_FETCH)
+ foreach(entry IN LISTS data_fetch)
+ string(REPLACE "|" ";" tuple "${entry}")
+ list(GET tuple 0 file)
+ list(GET tuple 1 name)
+ list(GET tuple 2 ext)
+ set(stamp "${ext}-stamp")
+ if(NOT DEFINED "_ExternalData_FILE_${file}")
+ set("_ExternalData_FILE_${file}" 1)
+ add_custom_command(
+ # Users care about the data file, so hide the hash/timestamp file.
+ COMMENT "Generating ${file}"
+ # The hash/timestamp file is the output from the build perspective.
+ # List the real file as a second output in case it is a broken link.
+ # The files must be listed in this order so CMake can hide from the
+ # make tool that a symlink target may not be newer than the input.
+ OUTPUT "${file}${stamp}" "${file}"
+ # Run the data fetch/update script.
+ COMMAND ${CMAKE_COMMAND} -Drelative_top=${CMAKE_BINARY_DIR}
+ -Dfile=${file} -Dname=${name} -Dext=${ext}
+ -DExternalData_ACTION=fetch
+ -DExternalData_CONFIG=${config}
+ -P ${_ExternalData_SELF}
+ # Update whenever the object hash changes.
+ DEPENDS "${name}${ext}"
+ )
+ list(APPEND files "${file}${stamp}")
+ endif()
+ endforeach()
+
+ # Custom target to drive all update commands.
+ add_custom_target(${target} ALL DEPENDS ${files})
+endfunction()
+
+function(ExternalData_expand_arguments target outArgsVar)
+ # Replace DATA{} references with real arguments.
+ set(data_regex "DATA{([^{}\r\n]*)}")
+ set(other_regex "([^D]|D[^A]|DA[^T]|DAT[^A]|DATA[^{])+|.")
+ set(outArgs "")
+ foreach(arg IN LISTS ARGN)
+ if("x${arg}" MATCHES "${data_regex}")
+ # Split argument into DATA{}-pieces and other pieces.
+ string(REGEX MATCHALL "${data_regex}|${other_regex}" pieces "${arg}")
+ # Compose output argument with DATA{}-pieces replaced.
+ set(outArg "")
+ foreach(piece IN LISTS pieces)
+ if("x${piece}" MATCHES "^x${data_regex}$")
+ # Replace this DATA{}-piece with a file path.
+ string(REGEX REPLACE "${data_regex}" "\\1" data "${piece}")
+ _ExternalData_arg("${target}" "${piece}" "${data}" file)
+ set(outArg "${outArg}${file}")
+ else()
+ # No replacement needed for this piece.
+ set(outArg "${outArg}${piece}")
+ endif()
+ endforeach()
+ list(APPEND outArgs "${outArg}")
+ else()
+ # No replacements needed in this argument.
+ list(APPEND outArgs "${arg}")
+ endif()
+ endforeach()
+ set("${outArgsVar}" "${outArgs}" PARENT_SCOPE)
+endfunction()
+
+#-----------------------------------------------------------------------------
+# Private helper interface
+
+set(_ExternalData_SELF "${CMAKE_CURRENT_LIST_FILE}")
+get_filename_component(_ExternalData_SELF_DIR "${_ExternalData_SELF}" PATH)
+
+function(_ExternalData_compute_hash var_hash algo file)
+ if("${algo}" STREQUAL "MD5")
+ # TODO: Errors
+ execute_process(COMMAND "${CMAKE_COMMAND}" -E md5sum "${file}"
+ OUTPUT_VARIABLE output)
+ string(SUBSTRING "${output}" 0 32 hash)
+ set("${var_hash}" "${hash}" PARENT_SCOPE)
+ else()
+ # TODO: Other hashes.
+ message(FATAL_ERROR "Hash algorithm ${algo} unimplemented.")
+ endif()
+endfunction()
+
+function(_ExternalData_random var)
+ if(NOT ${CMAKE_VERSION} VERSION_LESS 2.8.5)
+ string(RANDOM LENGTH 6 random)
+ elseif(EXISTS /dev/urandom)
+ file(READ /dev/urandom random LIMIT 4 HEX)
+ else()
+ message(FATAL_ERROR "CMake >= 2.8.5 required in this environment")
+ endif()
+ set("${var}" "${random}" PARENT_SCOPE)
+endfunction()
+
+function(_ExternalData_exact_regex regex_var string)
+ string(REGEX REPLACE "([][+.*()^])" "\\\\\\1" regex "${string}")
+ set("${regex_var}" "${regex}" PARENT_SCOPE)
+endfunction()
+
+function(_ExternalData_atomic_write file content)
+ _ExternalData_random(random)
+ set(tmp "${file}.tmp${random}")
+ file(WRITE "${tmp}" "${content}")
+ file(RENAME "${tmp}" "${file}")
+endfunction()
+
+function(_ExternalData_link_content name var_ext)
+ if("${ExternalData_LINK_CONTENT}" MATCHES "^(MD5)$")
+ set(algo "${ExternalData_LINK_CONTENT}")
+ else()
+ message(FATAL_ERROR
+ "Unknown hash algorithm specified by ExternalData_LINK_CONTENT:\n"
+ " ${ExternalData_LINK_CONTENT}")
+ endif()
+ _ExternalData_compute_hash(hash "${algo}" "${name}")
+ get_filename_component(dir "${name}" PATH)
+ set(staged "${dir}/.ExternalData_${algo}_${hash}")
+ set(ext ".md5")
+ _ExternalData_atomic_write("${name}${ext}" "${hash}\n")
+ file(RENAME "${name}" "${staged}")
+ set("${var_ext}" "${ext}" PARENT_SCOPE)
+
+ file(RELATIVE_PATH relname "${ExternalData_SOURCE_ROOT}" "${name}${ext}")
+ message(STATUS "Linked ${relname} to ExternalData ${algo}/${hash}")
+endfunction()
+
+function(_ExternalData_arg target arg options var_file)
+ # Separate data path from the options.
+ string(REPLACE "," ";" options "${options}")
+ list(GET options 0 data)
+ list(REMOVE_AT options 0)
+
+ # Convert to full path.
+ if(IS_ABSOLUTE "${data}")
+ set(absdata "${data}")
+ else()
+ # TODO: If ${data} does not start in "./" or "../" then use search path?
+ get_filename_component(absdata "${CMAKE_CURRENT_SOURCE_DIR}/${data}" ABSOLUTE)
+ endif()
+
+ # Convert to relative path under the source tree.
+ if(NOT ExternalData_SOURCE_ROOT)
+ set(ExternalData_SOURCE_ROOT "${CMAKE_SOURCE_DIR}")
+ endif()
+ set(top_src "${ExternalData_SOURCE_ROOT}")
+ file(RELATIVE_PATH reldata "${top_src}" "${absdata}")
+ if(IS_ABSOLUTE "${reldata}" OR "${reldata}" MATCHES "^\\.\\./")
+ message(FATAL_ERROR "Data file referenced by argument\n"
+ " ${arg}\n"
+ "does not lie under the top-level source directory\n"
+ " ${top_src}\n")
+ endif()
+ if(NOT ExternalData_BINARY_ROOT)
+ set(ExternalData_BINARY_ROOT "${CMAKE_BINARY_DIR}")
+ endif()
+ set(top_bin "${ExternalData_BINARY_ROOT}")
+
+ # Handle in-source builds gracefully.
+ if("${top_src}" STREQUAL "${top_bin}")
+ if(ExternalData_LINK_CONTENT)
+ message(WARNING "ExternalData_LINK_CONTENT cannot be used in-source")
+ set(ExternalData_LINK_CONTENT 0)
+ endif()
+ set(top_same 1)
+ endif()
+
+ set(external "") # Entries external to the source tree.
+ set(internal "") # Entries internal to the source tree.
+ set(have_original 0)
+
+ # Process options.
+ set(associated_files "")
+ set(associated_regex "")
+ foreach(opt ${options})
+ if("x${opt}" MATCHES "^xREGEX:[^:/]+$")
+ # Regular expression to match associated files.
+ string(REGEX REPLACE "^REGEX:" "" regex "${opt}")
+ list(APPEND associated_regex "${regex}")
+ elseif("x${opt}" MATCHES "^[^][:/*?]+$")
+ # Specific associated file.
+ list(APPEND associated_files "${opt}")
+ else()
+ message(FATAL_ERROR "Unknown option \"${opt}\" in argument\n"
+ " ${arg}\n")
+ endif()
+ endforeach()
+
+ if(associated_files OR associated_regex)
+ # Load the named data file and listed/matching associated files.
+ _ExternalData_arg_single()
+ _ExternalData_arg_associated()
+ elseif("${reldata}" MATCHES "(^|/)[^/.]+$")
+ # Files with no extension cannot be a series.
+ _ExternalData_arg_single()
+ else()
+ # Match a whole file series by default.
+ _ExternalData_arg_series()
+ endif()
+
+ if(NOT have_original)
+ message(FATAL_ERROR "Data file referenced by argument\n"
+ " ${arg}\n"
+ "corresponds to source tree path\n"
+ " ${reldata}\n"
+ "that does not exist (with or without an extension)!")
+ endif()
+
+ if(external)
+ # Make the series available in the build tree.
+ set_property(GLOBAL APPEND PROPERTY
+ _ExternalData_${target}_FETCH "${external}")
+ set_property(GLOBAL APPEND PROPERTY
+ _ExternalData_${target}_LOCAL "${internal}")
+ set("${var_file}" "${top_bin}/${reldata}" PARENT_SCOPE)
+ else()
+ # The whole series is in the source tree.
+ set("${var_file}" "${top_src}/${reldata}" PARENT_SCOPE)
+ endif()
+endfunction()
+
+macro(_ExternalData_arg_associated)
+ # Associated files lie in the same directory.
+ get_filename_component(reldir "${reldata}" PATH)
+ if(reldir)
+ set(reldir "${reldir}/")
+ endif()
+ _ExternalData_exact_regex(reldir_regex "${reldir}")
+
+ # Find files named explicitly.
+ foreach(file ${associated_files})
+ _ExternalData_exact_regex(file_regex "${file}")
+ _ExternalData_arg_find_files("${reldir}${file}" "${reldir_regex}${file_regex}")
+ endforeach()
+
+ # Find files matching the given regular expressions.
+ set(all "")
+ set(sep "")
+ foreach(regex ${associated_regex})
+ set(all "${all}${sep}${reldir_regex}${regex}")
+ set(sep "|")
+ endforeach()
+ _ExternalData_arg_find_files("${reldir}" "${all}")
+endmacro()
+
+macro(_ExternalData_arg_single)
+ # Match only the named data by itself.
+ _ExternalData_exact_regex(data_regex "${reldata}")
+ _ExternalData_arg_find_files("${reldata}" "${data_regex}")
+endmacro()
+
+macro(_ExternalData_arg_series)
+ # Configure series parsing and matching.
+ if(ExternalData_SERIES_PARSE)
+ if(NOT "${ExternalData_SERIES_PARSE}" MATCHES
+ "^\\^\\([^()]*\\)\\([^()]*\\)\\([^()]*\\)\\$$")
+ message(FATAL_ERROR
+ "ExternalData_SERIES_PARSE is set to\n"
+ " ${ExternalData_SERIES_PARSE}\n"
+ "which is not of the form\n"
+ " ^(...)(...)(...)$\n")
+ endif()
+ set(series_parse "${ExternalData_SERIES_PARSE}")
+ else()
+ set(series_parse "^(.*)()(\\.[^./]*)$")
+ endif()
+ if(ExternalData_SERIES_MATCH)
+ set(series_match "${ExternalData_SERIES_MATCH}")
+ else()
+ set(series_match "[_.]?[0-9]*")
+ endif()
+
+ # Parse the base, number, and extension components of the series.
+ string(REGEX REPLACE "${series_parse}" "\\1;\\2;\\3" tuple "${reldata}")
+ list(LENGTH tuple len)
+ if(NOT "${len}" EQUAL 3)
+ message(FATAL_ERROR "Data file referenced by argument\n"
+ " ${arg}\n"
+ "corresponds to path\n"
+ " ${reldata}\n"
+ "that does not match regular expression\n"
+ " ${series_parse}")
+ endif()
+ list(GET tuple 0 relbase)
+ list(GET tuple 2 ext)
+
+ # Glob files that might match the series.
+ # Then match match base, number, and extension.
+ _ExternalData_exact_regex(series_base "${relbase}")
+ _ExternalData_exact_regex(series_ext "${ext}")
+ _ExternalData_arg_find_files("${relbase}*${ext}"
+ "${series_base}${series_match}${series_ext}")
+endmacro()
+
+function(_ExternalData_arg_find_files pattern regex)
+ file(GLOB globbed RELATIVE "${top_src}" "${top_src}/${pattern}*")
+ foreach(entry IN LISTS globbed)
+ string(REGEX REPLACE "^(${regex})(\\.md5|)$" "\\1;\\2" tuple "${entry}")
+ list(LENGTH tuple len)
+ if("${len}" EQUAL 2)
+ list(GET tuple 0 relname)
+ list(GET tuple 1 alg)
+ set(name "${top_src}/${relname}")
+ set(file "${top_bin}/${relname}")
+ if(alg)
+ list(APPEND external "${file}|${name}|${alg}")
+ elseif(ExternalData_LINK_CONTENT)
+ _ExternalData_link_content("${name}" alg)
+ list(APPEND external "${file}|${name}|${alg}")
+ elseif(NOT top_same)
+ list(APPEND internal "${file}|${name}")
+ endif()
+ if("${relname}" STREQUAL "${reldata}")
+ set(have_original 1)
+ endif()
+ endif()
+ endforeach()
+ set(external "${external}" PARENT_SCOPE)
+ set(internal "${internal}" PARENT_SCOPE)
+ set(have_original "${have_original}" PARENT_SCOPE)
+endfunction()
+
+#-----------------------------------------------------------------------------
+# Private script mode interface
+
+if(CMAKE_GENERATOR OR NOT ExternalData_ACTION)
+ return()
+endif()
+
+if(ExternalData_CONFIG)
+ include(${ExternalData_CONFIG})
+endif()
+if(NOT ExternalData_URL_TEMPLATES)
+ message(FATAL_ERROR "No ExternalData_URL_TEMPLATES set!")
+endif()
+
+function(_ExternalData_link_or_copy src dst)
+ # Create a temporary file first.
+ get_filename_component(dst_dir "${dst}" PATH)
+ file(MAKE_DIRECTORY "${dst_dir}")
+ _ExternalData_random(random)
+ set(tmp "${dst}.tmp${random}")
+ if(UNIX)
+ # Create a symbolic link.
+ set(tgt "${src}")
+ if(relative_top)
+ # Use relative path if files are close enough.
+ file(RELATIVE_PATH relsrc "${relative_top}" "${src}")
+ file(RELATIVE_PATH relfile "${relative_top}" "${dst}")
+ if(NOT IS_ABSOLUTE "${relsrc}" AND NOT "${relsrc}" MATCHES "^\\.\\./" AND
+ NOT IS_ABSOLUTE "${reldst}" AND NOT "${reldst}" MATCHES "^\\.\\./")
+ file(RELATIVE_PATH tgt "${dst_dir}" "${src}")
+ endif()
+ endif()
+ execute_process(COMMAND "${CMAKE_COMMAND}" -E create_symlink "${tgt}" "${tmp}" RESULT_VARIABLE result)
+ else()
+ # Create a copy.
+ execute_process(COMMAND "${CMAKE_COMMAND}" -E copy "${src}" "${tmp}" RESULT_VARIABLE result)
+ endif()
+ if(result)
+ file(REMOVE "${tmp}")
+ message(FATAL_ERROR "Failed to create\n ${tmp}\nfrom\n ${obj}")
+ endif()
+
+ # Atomically create/replace the real destination.
+ file(RENAME "${tmp}" "${dst}")
+endfunction()
+
+function(_ExternalData_download_file url file err_var msg_var)
+ set(retry 3)
+ while(retry)
+ math(EXPR retry "${retry} - 1")
+ if("${CMAKE_VERSION}" VERSION_GREATER 2.8.4.20110602)
+ if(ExternalData_TIMEOUT_INACTIVITY)
+ set(inactivity_timeout INACTIVITY_TIMEOUT ${ExternalData_TIMEOUT_INACTIVITY})
+ elseif(NOT "${ExternalData_TIMEOUT_INACTIVITY}" EQUAL 0)
+ set(inactivity_timeout INACTIVITY_TIMEOUT 60)
+ else()
+ set(inactivity_timeout "")
+ endif()
+ else()
+ set(inactivity_timeout "")
+ endif()
+ if(ExternalData_TIMEOUT_ABSOLUTE)
+ set(absolute_timeout TIMEOUT ${ExternalData_TIMEOUT_ABSOLUTE})
+ elseif(NOT "${ExternalData_TIMEOUT_ABSOLUTE}" EQUAL 0)
+ set(absolute_timeout TIMEOUT 300)
+ else()
+ set(absolute_timeout "")
+ endif()
+ file(DOWNLOAD "${url}" "${file}" STATUS status LOG log ${inactivity_timeout} ${absolute_timeout} SHOW_PROGRESS)
+ list(GET status 0 err)
+ list(GET status 1 msg)
+ if(err)
+ if("${msg}" MATCHES "HTTP response code said error" AND
+ "${log}" MATCHES "error: 503")
+ set(msg "temporarily unavailable")
+ endif()
+ elseif("${log}" MATCHES "\nHTTP[^\n]* 503")
+ set(err TRUE)
+ set(msg "temporarily unavailable")
+ endif()
+ if(NOT err OR NOT "${msg}" MATCHES "partial|timeout|temporarily")
+ break()
+ elseif(retry)
+ message(STATUS "[download terminated: ${msg}, retries left: ${retry}]")
+ endif()
+ endwhile()
+ set("${err_var}" "${err}" PARENT_SCOPE)
+ set("${msg_var}" "${msg}" PARENT_SCOPE)
+endfunction()
+
+function(_ExternalData_download_object name hash algo var_obj)
+ # Search all object stores for an existing object.
+ foreach(dir ${ExternalData_OBJECT_STORES})
+ set(obj "${dir}/${algo}/${hash}")
+ if(EXISTS "${obj}")
+ message(STATUS "Found object: \"${obj}\"")
+ set("${var_obj}" "${obj}" PARENT_SCOPE)
+ return()
+ endif()
+ endforeach()
+
+ # Download object to the first store.
+ list(GET ExternalData_OBJECT_STORES 0 store)
+ set(obj "${store}/${algo}/${hash}")
+
+ _ExternalData_random(random)
+ set(tmp "${obj}.tmp${random}")
+ set(found 0)
+ set(tried "")
+ foreach(url_template IN LISTS ExternalData_URL_TEMPLATES)
+ string(REPLACE "%(hash)" "${hash}" url_tmp "${url_template}")
+ string(REPLACE "%(algo)" "${algo}" url "${url_tmp}")
+ message(STATUS "Fetching \"${url}\"")
+ _ExternalData_download_file("${url}" "${tmp}" err errMsg)
+ set(tried "${tried}\n ${url}")
+ if(err)
+ set(tried "${tried} (${errMsg})")
+ else()
+ # Verify downloaded object.
+ _ExternalData_compute_hash(dl_hash "${algo}" "${tmp}")
+ if("${dl_hash}" STREQUAL "${hash}")
+ set(found 1)
+ break()
+ else()
+ set(tried "${tried} (wrong hash ${algo}=${dl_hash})")
+ if("$ENV{ExternalData_DEBUG_DOWNLOAD}" MATCHES ".")
+ file(RENAME "${tmp}" "${store}/${algo}/${dl_hash}")
+ endif()
+ endif()
+ endif()
+ file(REMOVE "${tmp}")
+ endforeach()
+
+ get_filename_component(dir "${name}" PATH)
+ set(staged "${dir}/.ExternalData_${algo}_${hash}")
+
+ if(found)
+ file(RENAME "${tmp}" "${obj}")
+ message(STATUS "Downloaded object: \"${obj}\"")
+ elseif(EXISTS "${staged}")
+ set(obj "${staged}")
+ message(STATUS "Staged object: \"${obj}\"")
+ else()
+ message(FATAL_ERROR "Object ${algo}=${hash} not found at:${tried}")
+ endif()
+
+ set("${var_obj}" "${obj}" PARENT_SCOPE)
+endfunction()
+
+if("${ExternalData_ACTION}" STREQUAL "fetch")
+ foreach(v ExternalData_OBJECT_STORES file name ext)
+ if(NOT DEFINED "${v}")
+ message(FATAL_ERROR "No \"-D${v}=\" value provided!")
+ endif()
+ endforeach()
+
+ file(READ "${name}${ext}" hash)
+ string(STRIP "${hash}" hash)
+
+ if("${ext}" STREQUAL ".md5")
+ set(algo "MD5")
+ else()
+ message(FATAL_ERROR "Unknown hash algorithm extension \"${ext}\"")
+ endif()
+
+ _ExternalData_download_object("${name}" "${hash}" "${algo}" obj)
+
+ # Check if file already corresponds to the object.
+ set(stamp "${ext}-stamp")
+ set(file_up_to_date 0)
+ if(EXISTS "${file}" AND EXISTS "${file}${stamp}")
+ file(READ "${file}${stamp}" f_hash)
+ string(STRIP "${f_hash}" f_hash)
+ if("${f_hash}" STREQUAL "${hash}")
+ #message(STATUS "File already corresponds to object")
+ set(file_up_to_date 1)
+ endif()
+ endif()
+
+ if(file_up_to_date)
+ # Touch the file to convince the build system it is up to date.
+ execute_process(COMMAND "${CMAKE_COMMAND}" -E touch "${file}")
+ else()
+ _ExternalData_link_or_copy("${obj}" "${file}")
+ endif()
+
+ # Atomically update the hash/timestamp file to record the object referenced.
+ _ExternalData_atomic_write("${file}${stamp}" "${hash}\n")
+elseif("${ExternalData_ACTION}" STREQUAL "local")
+ foreach(v file name)
+ if(NOT DEFINED "${v}")
+ message(FATAL_ERROR "No \"-D${v}=\" value provided!")
+ endif()
+ endforeach()
+ _ExternalData_link_or_copy("${name}" "${file}")
+elseif("${ExternalData_ACTION}" STREQUAL "store")
+ foreach(v dir file)
+ if(NOT DEFINED "${v}")
+ message(FATAL_ERROR "No \"-D${v}=\" value provided!")
+ endif()
+ endforeach()
+ if(NOT DEFINED algo)
+ set(algo "MD5")
+ endif()
+ _ExternalData_compute_hash(hash "${algo}" "${file}")
+else()
+ message(FATAL_ERROR "Unknown ExternalData_ACTION=[${ExternalData_ACTION}]")
+endif()