Merge branch 'ps/build-meson-fixes-0130'

Assorted fixes and improvements to the build procedure based on
meson.

* ps/build-meson-fixes-0130:
  gitlab-ci: restrict maximum number of link jobs on Windows
  meson: consistently use custom program paths to resolve programs
  meson: fix overwritten `git` variable
  meson: prevent finding sed(1) in a loop
  meson: improve handling of `sane_tool_path` option
  meson: improve PATH handling
  meson: drop separate version library
  meson: stop linking libcurl into all executables
  meson: introduce `libgit_curl` dependency
  meson: simplify use of the common-main library
  meson: inline the static 'git' library
  meson: fix OpenSSL fallback when not explicitly required
  meson: fix exec path with enabled runtime prefix

8 files changed, 89 insertions, 98 deletions

diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 3f29181708..86996fe941 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -164,7 +164,7 @@ build:msvc-meson:
   extends: .msvc-meson
   stage: build
   script:
-    - meson setup build -Dperl=disabled
+    - meson setup build -Dperl=disabled -Dbackend_max_links=1
     - meson compile -C build
   artifacts:
     paths:
diff --git a/Documentation/howto/meson.build b/Documentation/howto/meson.build
index c023c10416..92a08b13ee 100644
--- a/Documentation/howto/meson.build
+++ b/Documentation/howto/meson.build
@@ -41,7 +41,7 @@ custom_target(
 foreach howto : howto_sources
   howto_stripped = custom_target(
     command: [
-      find_program('sed'),
+      sed,
       '-e',
       '1,/^$/d',
       '@INPUT@',
diff --git a/Documentation/meson.build b/Documentation/meson.build
index 1129ce4c85..0a0f2bfa14 100644
--- a/Documentation/meson.build
+++ b/Documentation/meson.build
@@ -207,9 +207,9 @@ manpages = {
 
 docs_backend = get_option('docs_backend')
 if docs_backend == 'auto'
-  if find_program('asciidoc', required: false).found()
+  if find_program('asciidoc', dirs: program_path, required: false).found()
     docs_backend = 'asciidoc'
-  elif find_program('asciidoctor', required: false).found()
+  elif find_program('asciidoctor', dirs: program_path, required: false).found()
     docs_backend = 'asciidoctor'
   else
     error('Neither asciidoc nor asciidoctor were found.')
@@ -217,7 +217,7 @@ if docs_backend == 'auto'
 endif
 
 if docs_backend == 'asciidoc'
-  asciidoc = find_program('asciidoc', required: true)
+  asciidoc = find_program('asciidoc', dirs: program_path)
   asciidoc_html = 'xhtml11'
   asciidoc_docbook = 'docbook'
   xmlto_extra = [ ]
@@ -246,7 +246,7 @@ if docs_backend == 'asciidoc'
     asciidoc_conf,
   ]
 elif docs_backend == 'asciidoctor'
-  asciidoctor = find_program('asciidoctor', required: true)
+  asciidoctor = find_program('asciidoctor', dirs: program_path)
   asciidoc_html = 'xhtml5'
   asciidoc_docbook = 'docbook5'
   xmlto_extra = [
@@ -284,8 +284,7 @@ elif docs_backend == 'asciidoctor'
   ]
 endif
 
-git = find_program('git', required: false)
-xmlto = find_program('xmlto')
+xmlto = find_program('xmlto', dirs: program_path)
 
 cmd_lists = [
   'cmds-ancillaryinterrogators.adoc',
@@ -406,7 +405,7 @@ if get_option('docs').contains('html')
     pointing_to: 'git.html',
   )
 
-  xsltproc = find_program('xsltproc')
+  xsltproc = find_program('xsltproc', dirs: program_path)
 
   user_manual_xml = custom_target(
     command: asciidoc_common_options + [
diff --git a/meson.build b/meson.build
index 021a182135..516207f9cf 100644
--- a/meson.build
+++ b/meson.build
@@ -191,30 +191,29 @@ project('git', 'c',
 fs = import('fs')
 
 program_path = []
-# Git for Windows provides all the tools we need to build Git.
-if host_machine.system() == 'windows'
-  program_path += [ 'C:/Program Files/Git/bin', 'C:/Program Files/Git/usr/bin' ]
+if get_option('sane_tool_path').length() != 0
+  program_path = get_option('sane_tool_path')
+elif host_machine.system() == 'windows'
+  # Git for Windows provides all the tools we need to build Git.
+  program_path = [ 'C:/Program Files/Git/bin', 'C:/Program Files/Git/usr/bin' ]
 endif
 
 cygpath = find_program('cygpath', dirs: program_path, required: false)
 diff = find_program('diff', dirs: program_path)
+git = find_program('git', dirs: program_path, required: false)
+sed = find_program('sed', dirs: program_path)
 shell = find_program('sh', dirs: program_path)
 tar = find_program('tar', dirs: program_path)
 
-script_environment = environment()
-foreach tool : ['cat', 'cut', 'grep', 'sed', 'sort', 'tr', 'uname']
-  program = find_program(tool, dirs: program_path)
-  script_environment.prepend('PATH', fs.parent(program.full_path()))
+# Sanity-check that programs required for the build exist.
+foreach tool : ['cat', 'cut', 'grep', 'sort', 'tr', 'uname']
+  find_program(tool, dirs: program_path)
 endforeach
 
-git = find_program('git', dirs: program_path, required: false)
-if git.found()
-  script_environment.prepend('PATH', fs.parent(git.full_path()))
-endif
-
-if get_option('sane_tool_path') != ''
-  script_environment.prepend('PATH', get_option('sane_tool_path'))
-endif
+script_environment = environment()
+foreach path : program_path
+  script_environment.prepend('PATH', path)
+endforeach
 
 # The environment used by GIT-VERSION-GEN. Note that we explicitly override
 # environment variables that might be set by the user. This is by design so
@@ -479,6 +478,7 @@ libgit_sources = [
   'userdiff.c',
   'utf8.c',
   'varint.c',
+  'version.c',
   'versioncmp.c',
   'walker.c',
   'wildmatch.c',
@@ -678,8 +678,9 @@ else
   build_options_config.set('WITH_BREAKING_CHANGES', '')
 endif
 
-if get_option('sane_tool_path') != ''
-  build_options_config.set_quoted('BROKEN_PATH_FIX', 's|^\# @BROKEN_PATH_FIX@$|git_broken_path_fix "' + get_option('sane_tool_path') + '"|')
+if get_option('sane_tool_path').length() != 0
+  sane_tool_path = (host_machine.system() == 'windows' ? ';' : ':').join(get_option('sane_tool_path'))
+  build_options_config.set_quoted('BROKEN_PATH_FIX', 's|^\# @BROKEN_PATH_FIX@$|git_broken_path_fix "' + sane_tool_path + '"|')
 else
   build_options_config.set_quoted('BROKEN_PATH_FIX', '/^\# @BROKEN_PATH_FIX@$/d')
 endif
@@ -699,7 +700,6 @@ libgit_c_args = [
   '-DETC_GITATTRIBUTES="' + get_option('gitattributes') + '"',
   '-DETC_GITCONFIG="' + get_option('gitconfig') + '"',
   '-DFALLBACK_RUNTIME_PREFIX="' + get_option('prefix') + '"',
-  '-DGIT_EXEC_PATH="' + get_option('prefix') / get_option('libexecdir') / 'git-core"',
   '-DGIT_HOST_CPU="' + host_machine.cpu_family() + '"',
   '-DGIT_HTML_PATH="' + get_option('datadir') / 'doc/git-doc"',
   '-DGIT_INFO_PATH="' + get_option('infodir') + '"',
@@ -963,7 +963,9 @@ if curl.found()
     use_curl_for_imap_send = true
   endif
 
-  libgit_dependencies += curl
+  # Most executables don't have to link against libcurl, but we still need its
+  # include directories so that we can resolve LIBCURL_VERSION in "help.c".
+  libgit_dependencies += curl.partial_dependency(includes: true)
   libgit_c_args += '-DCURL_DISABLE_TYPECHECK'
   build_options_config.set('NO_CURL', '')
 else
@@ -1388,7 +1390,11 @@ if https_backend == 'auto' and security_framework.found()
 endif
 
 openssl_required = 'openssl' in [csprng_backend, https_backend, sha1_backend, sha1_unsafe_backend, sha256_backend]
-openssl = dependency('openssl', required: openssl_required, default_options: ['default_library=static'])
+openssl = dependency('openssl',
+  required: openssl_required,
+  allow_fallback: openssl_required or https_backend == 'auto',
+  default_options: ['default_library=static'],
+)
 if https_backend == 'auto' and openssl.found()
   https_backend = 'openssl'
 endif
@@ -1402,6 +1408,7 @@ elif https_backend == 'openssl'
 else
   # We either couldn't find any dependencies with 'auto' or the user requested
   # 'none'. Both cases are benign.
+  https_backend = 'none'
 endif
 
 if https_backend != 'openssl'
@@ -1501,6 +1508,7 @@ endif
 if get_option('runtime_prefix')
   libgit_c_args += '-DRUNTIME_PREFIX'
   build_options_config.set('RUNTIME_PREFIX', 'true')
+  git_exec_path = get_option('libexecdir') / 'git-core'
 
   if compiler.has_header('mach-o/dyld.h')
     libgit_c_args += '-DHAVE_NS_GET_EXECUTABLE_PATH'
@@ -1537,7 +1545,9 @@ if get_option('runtime_prefix')
   endif
 else
   build_options_config.set('RUNTIME_PREFIX', 'false')
+  git_exec_path = get_option('prefix') / get_option('libexecdir') / 'git-core'
 endif
+libgit_c_args += '-DGIT_EXEC_PATH="' + git_exec_path + '"'
 
 git_version_file = custom_target(
   command: [
@@ -1568,32 +1578,18 @@ version_def_h = custom_target(
   depends: [git_version_file],
   env: version_gen_environment,
 )
-
-# Build a separate library for "version.c" so that we do not have to rebuild
-# everything when the current Git commit changes.
-libgit_version_library = static_library('git-version',
-  sources: [
-    'version.c',
-    version_def_h,
-  ],
-  c_args: libgit_c_args + [
-    '-DGIT_VERSION_H="' + version_def_h.full_path() + '"',
-  ],
-  dependencies: libgit_dependencies,
-  include_directories: libgit_include_directories,
-)
-
-libgit_library = static_library('git',
-  sources: libgit_sources,
-  c_args: libgit_c_args,
-  link_with: libgit_version_library,
-  dependencies: libgit_dependencies,
-  include_directories: libgit_include_directories,
-)
+libgit_sources += version_def_h
 
 libgit = declare_dependency(
+  link_with: static_library('git',
+    sources: libgit_sources,
+    c_args: libgit_c_args + [
+      '-DGIT_VERSION_H="' + version_def_h.full_path() + '"',
+    ],
+    dependencies: libgit_dependencies,
+    include_directories: libgit_include_directories,
+  ),
   compile_args: libgit_c_args,
-  link_with: libgit_library,
   dependencies: libgit_dependencies,
   include_directories: libgit_include_directories,
 )
@@ -1634,88 +1630,89 @@ if host_machine.system() == 'windows'
     error('Unsupported compiler ' + compiler.get_id())
   endif
 endif
-common_main_library = static_library('common-main',
-  sources: common_main_sources,
-  c_args: libgit_c_args,
-  dependencies: libgit_dependencies,
-  include_directories: libgit_include_directories,
-)
-common_main = declare_dependency(
-  link_with: common_main_library,
+
+libgit_commonmain = declare_dependency(
+  link_with: static_library('common-main',
+    sources: common_main_sources,
+    dependencies: [ libgit ],
+  ),
   link_args: common_main_link_args,
+  dependencies: [ libgit ],
 )
 
 bin_wrappers = [ ]
 test_dependencies = [ ]
 
-git = executable('git',
+git_builtin = executable('git',
   sources: builtin_sources + 'git.c',
-  dependencies: [libgit, common_main],
+  dependencies: [libgit_commonmain],
   install: true,
   install_dir: get_option('libexecdir') / 'git-core',
 )
-bin_wrappers += git
+bin_wrappers += git_builtin
 
 test_dependencies += executable('git-daemon',
   sources: 'daemon.c',
-  dependencies: [libgit, common_main],
+  dependencies: [libgit_commonmain],
   install: true,
   install_dir: get_option('libexecdir') / 'git-core',
 )
 
 test_dependencies += executable('git-sh-i18n--envsubst',
   sources: 'sh-i18n--envsubst.c',
-  dependencies: [libgit, common_main],
+  dependencies: [libgit_commonmain],
   install: true,
   install_dir: get_option('libexecdir') / 'git-core',
 )
 
 bin_wrappers += executable('git-shell',
   sources: 'shell.c',
-  dependencies: [libgit, common_main],
+  dependencies: [libgit_commonmain],
   install: true,
   install_dir: get_option('libexecdir') / 'git-core',
 )
 
 test_dependencies += executable('git-http-backend',
   sources: 'http-backend.c',
-  dependencies: [libgit, common_main],
+  dependencies: [libgit_commonmain],
   install: true,
   install_dir: get_option('libexecdir') / 'git-core',
 )
 
 bin_wrappers += executable('scalar',
   sources: 'scalar.c',
-  dependencies: [libgit, common_main],
+  dependencies: [libgit_commonmain],
   install: true,
   install_dir: get_option('libexecdir') / 'git-core',
 )
 
 if get_option('curl').enabled()
-  curl_sources = [
-    'http.c',
-    'http-walker.c',
-  ]
+  libgit_curl = declare_dependency(
+    sources: [
+      'http.c',
+      'http-walker.c',
+    ],
+    dependencies: [libgit_commonmain, curl],
+  )
 
-  git_remote_http = executable('git-remote-http',
-    sources: curl_sources + 'remote-curl.c',
-    dependencies: [libgit, common_main],
+  test_dependencies += executable('git-remote-http',
+    sources: 'remote-curl.c',
+    dependencies: [libgit_curl],
     install: true,
     install_dir: get_option('libexecdir') / 'git-core',
   )
-  test_dependencies += git_remote_http
 
   test_dependencies += executable('git-http-fetch',
-    sources: curl_sources + 'http-fetch.c',
-    dependencies: [libgit, common_main],
+    sources: 'http-fetch.c',
+    dependencies: [libgit_curl],
     install: true,
     install_dir: get_option('libexecdir') / 'git-core',
   )
 
   if expat.found()
     test_dependencies += executable('git-http-push',
-      sources: curl_sources + 'http-push.c',
-      dependencies: [libgit, common_main],
+      sources: 'http-push.c',
+      dependencies: [libgit_curl],
       install: true,
       install_dir: get_option('libexecdir') / 'git-core',
     )
@@ -1723,8 +1720,8 @@ if get_option('curl').enabled()
 
   foreach alias : [ 'git-remote-https', 'git-remote-ftp', 'git-remote-ftps' ]
     test_dependencies += executable(alias,
-      objects: git_remote_http.extract_all_objects(recursive: false),
-      dependencies: [libgit, common_main],
+      sources: 'remote-curl.c',
+      dependencies: [libgit_curl],
     )
 
     install_symlink(alias + executable_suffix,
@@ -1734,22 +1731,17 @@ if get_option('curl').enabled()
   endforeach
 endif
 
-imap_send_sources = ['imap-send.c']
-if use_curl_for_imap_send
-  imap_send_sources += curl_sources
-endif
-
 test_dependencies += executable('git-imap-send',
-  sources: imap_send_sources,
-  dependencies: [libgit, common_main],
+  sources: 'imap-send.c',
+  dependencies: [ use_curl_for_imap_send ? libgit_curl : libgit_commonmain ],
   install: true,
   install_dir: get_option('libexecdir') / 'git-core',
 )
 
 foreach alias : [ 'git-receive-pack', 'git-upload-archive', 'git-upload-pack' ]
   bin_wrappers += executable(alias,
-    objects: git.extract_all_objects(recursive: false),
-    dependencies: [libgit, common_main],
+    objects: git_builtin.extract_all_objects(recursive: false),
+    dependencies: [libgit_commonmain],
   )
 
   install_symlink(alias + executable_suffix,
diff --git a/meson_options.txt b/meson_options.txt
index 5c12e9055e..9e81379099 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -13,8 +13,8 @@ option('perl_cpan_fallback', type: 'boolean', value: true,
   description: 'Install bundled copies of CPAN modules that serve as a fallback in case the modules are not available on the system.')
 option('runtime_prefix', type: 'boolean', value: false,
   description: 'Resolve ancillary tooling and support files relative to the location of the runtime binary instead of hard-coding them into the binary.')
-option('sane_tool_path', type: 'string', value: '',
-  description: 'A colon-separated list of paths to prepend to PATH if your tools in /usr/bin are broken.')
+option('sane_tool_path', type: 'array', value: [],
+  description: 'An array of paths to pick up tools from in case the normal tools are broken or lacking.')
 
 # Build information compiled into Git and other parts like documentation.
 option('build_date', type: 'string', value: '',
diff --git a/oss-fuzz/meson.build b/oss-fuzz/meson.build
index ed79665501..878afd8426 100644
--- a/oss-fuzz/meson.build
+++ b/oss-fuzz/meson.build
@@ -15,6 +15,6 @@ foreach fuzz_program : fuzz_programs
       'dummy-cmd-main.c',
       fuzz_program,
     ],
-    dependencies: [libgit, common_main],
+    dependencies: [libgit_commonmain],
   )
 endforeach
diff --git a/t/helper/meson.build b/t/helper/meson.build
index 1d6154ce97..d2cabaa2bc 100644
--- a/t/helper/meson.build
+++ b/t/helper/meson.build
@@ -80,14 +80,14 @@ test_tool_sources = [
 
 test_tool = executable('test-tool',
   sources: test_tool_sources,
-  dependencies: [libgit, common_main],
+  dependencies: [libgit_commonmain],
 )
 bin_wrappers += test_tool
 test_dependencies += test_tool
 
 test_fake_ssh = executable('test-fake-ssh',
   sources: 'test-fake-ssh.c',
-  dependencies: [libgit, common_main],
+  dependencies: [libgit_commonmain],
 )
 bin_wrappers += test_fake_ssh
 test_dependencies += test_fake_ssh
diff --git a/t/meson.build b/t/meson.build
index 780939d49f..25ce072707 100644
--- a/t/meson.build
+++ b/t/meson.build
@@ -43,7 +43,7 @@ clar_sources += custom_target(
 
 clar_unit_tests = executable('unit-tests',
   sources: clar_sources + clar_test_suites,
-  dependencies: [libgit, common_main],
+  dependencies: [libgit_commonmain],
 )
 test('unit-tests', clar_unit_tests)
 
@@ -72,7 +72,7 @@ foreach unit_test_program : unit_test_programs
       'unit-tests/lib-reftable.c',
       unit_test_program,
     ],
-    dependencies: [libgit, common_main],
+    dependencies: [libgit_commonmain],
   )
   test(unit_test_name, unit_test,
     workdir: meson.current_source_dir(),