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-rw-r--r--Help/command/add_custom_command.rst14
-rw-r--r--Help/command/add_custom_target.rst14
-rw-r--r--Help/release/dev/command-job-server-aware.rst5
-rw-r--r--Source/cmAddCustomCommandCommand.cxx19
-rw-r--r--Source/cmAddCustomTargetCommand.cxx17
-rw-r--r--Source/cmGlobalBorlandMakefileGenerator.h2
-rw-r--r--Source/cmGlobalGenerator.h2
-rw-r--r--Source/cmGlobalJOMMakefileGenerator.h2
-rw-r--r--Source/cmGlobalNMakeMakefileGenerator.h2
-rw-r--r--Source/cmGlobalUnixMakefileGenerator3.h2
-rw-r--r--Source/cmGlobalWatcomWMakeGenerator.h2
-rw-r--r--Tests/RunCMake/CMakeLists.txt3
-rw-r--r--Tests/RunCMake/Make/DetectJobServer-absent-parallel-build-stderr.txt1
-rw-r--r--Tests/RunCMake/Make/DetectJobServer-absent.cmake13
-rw-r--r--Tests/RunCMake/Make/DetectJobServer-present.cmake13
-rw-r--r--Tests/RunCMake/Make/GNUMakeJobServerAware-check.cmake12
-rw-r--r--Tests/RunCMake/Make/GNUMakeJobServerAware.cmake12
-rw-r--r--Tests/RunCMake/Make/RunCMakeTest.cmake40
-rw-r--r--Tests/RunCMake/detect_jobserver.c204
19 files changed, 378 insertions, 1 deletions
diff --git a/Help/command/add_custom_command.rst b/Help/command/add_custom_command.rst
index 6dc6832..d523ba8 100644
--- a/Help/command/add_custom_command.rst
+++ b/Help/command/add_custom_command.rst
@@ -24,6 +24,7 @@ The first signature is for adding a custom command to produce an output:
[COMMENT comment]
[DEPFILE depfile]
[JOB_POOL job_pool]
+ [JOB_SERVER_AWARE <bool>]
[VERBATIM] [APPEND] [USES_TERMINAL]
[COMMAND_EXPAND_LISTS]
[DEPENDS_EXPLICIT_ONLY])
@@ -221,6 +222,19 @@ The options are:
Using a pool that is not defined by :prop_gbl:`JOB_POOLS` causes
an error by ninja at build time.
+``JOB_SERVER_AWARE``
+ .. versionadded:: 3.28
+
+ Specify that the command is GNU Make job server aware.
+
+ For the :generator:`Unix Makefiles`, :generator:`MSYS Makefiles`, and
+ :generator:`MinGW Makefiles` generators this will add the ``+`` prefix to the
+ recipe line. See the `GNU Make Documentation`_ for more information.
+
+ This option is silently ignored by other generators.
+
+.. _`GNU Make Documentation`: https://www.gnu.org/software/make/manual/html_node/MAKE-Variable.html
+
``MAIN_DEPENDENCY``
Specify the primary input source file to the command. This is
treated just like any value given to the ``DEPENDS`` option
diff --git a/Help/command/add_custom_target.rst b/Help/command/add_custom_target.rst
index 545b9a5..ef0c8d9 100644
--- a/Help/command/add_custom_target.rst
+++ b/Help/command/add_custom_target.rst
@@ -12,6 +12,7 @@ Add a target with no output so it will always be built.
[WORKING_DIRECTORY dir]
[COMMENT comment]
[JOB_POOL job_pool]
+ [JOB_SERVER_AWARE <bool>]
[VERBATIM] [USES_TERMINAL]
[COMMAND_EXPAND_LISTS]
[SOURCES src1 [src2...]])
@@ -146,6 +147,19 @@ The options are:
Using a pool that is not defined by :prop_gbl:`JOB_POOLS` causes
an error by ninja at build time.
+``JOB_SERVER_AWARE``
+ .. versionadded:: 3.28
+
+ Specify that the command is GNU Make job server aware.
+
+ For the :generator:`Unix Makefiles`, :generator:`MSYS Makefiles`, and
+ :generator:`MinGW Makefiles` generators this will add the ``+`` prefix to the
+ recipe line. See the `GNU Make Documentation`_ for more information.
+
+ This option is silently ignored by other generators.
+
+.. _`GNU Make Documentation`: https://www.gnu.org/software/make/manual/html_node/MAKE-Variable.html
+
``SOURCES``
Specify additional source files to be included in the custom target.
Specified source files will be added to IDE project files for
diff --git a/Help/release/dev/command-job-server-aware.rst b/Help/release/dev/command-job-server-aware.rst
new file mode 100644
index 0000000..224c739
--- /dev/null
+++ b/Help/release/dev/command-job-server-aware.rst
@@ -0,0 +1,5 @@
+command-job-server-aware
+------------------------
+
+* The :command:`add_custom_command` and :command:`add_custom_target`
+ commands gained a ``JOB_SERVER_AWARE`` option.
diff --git a/Source/cmAddCustomCommandCommand.cxx b/Source/cmAddCustomCommandCommand.cxx
index b1398db..044b5df 100644
--- a/Source/cmAddCustomCommandCommand.cxx
+++ b/Source/cmAddCustomCommandCommand.cxx
@@ -19,6 +19,7 @@
#include "cmPolicies.h"
#include "cmStringAlgorithms.h"
#include "cmSystemTools.h"
+#include "cmValue.h"
bool cmAddCustomCommandCommand(std::vector<std::string> const& args,
cmExecutionStatus& status)
@@ -39,6 +40,7 @@ bool cmAddCustomCommandCommand(std::vector<std::string> const& args,
std::string working;
std::string depfile;
std::string job_pool;
+ std::string job_server_aware;
std::string comment_buffer;
const char* comment = nullptr;
std::vector<std::string> depends;
@@ -78,6 +80,7 @@ bool cmAddCustomCommandCommand(std::vector<std::string> const& args,
doing_working_directory,
doing_depfile,
doing_job_pool,
+ doing_job_server_aware,
doing_nothing
};
@@ -95,6 +98,7 @@ bool cmAddCustomCommandCommand(std::vector<std::string> const& args,
MAKE_STATIC_KEYWORD(DEPFILE);
MAKE_STATIC_KEYWORD(IMPLICIT_DEPENDS);
MAKE_STATIC_KEYWORD(JOB_POOL);
+ MAKE_STATIC_KEYWORD(JOB_SERVER_AWARE);
MAKE_STATIC_KEYWORD(MAIN_DEPENDENCY);
MAKE_STATIC_KEYWORD(OUTPUT);
MAKE_STATIC_KEYWORD(OUTPUTS);
@@ -126,6 +130,7 @@ bool cmAddCustomCommandCommand(std::vector<std::string> const& args,
keyPRE_BUILD,
keyPRE_LINK,
keySOURCE,
+ keyJOB_SERVER_AWARE,
keyTARGET,
keyUSES_TERMINAL,
keyVERBATIM,
@@ -190,6 +195,8 @@ bool cmAddCustomCommandCommand(std::vector<std::string> const& args,
}
} else if (copy == keyJOB_POOL) {
doing = doing_job_pool;
+ } else if (copy == keyJOB_SERVER_AWARE) {
+ doing = doing_job_server_aware;
}
} else {
std::string filename;
@@ -226,6 +233,9 @@ bool cmAddCustomCommandCommand(std::vector<std::string> const& args,
case doing_job_pool:
job_pool = copy;
break;
+ case doing_job_server_aware:
+ job_server_aware = copy;
+ break;
case doing_working_directory:
working = copy;
break;
@@ -324,6 +334,15 @@ bool cmAddCustomCommandCommand(std::vector<std::string> const& args,
return false;
}
+ // If using a GNU Make generator and `JOB_SERVER_AWARE` is set then
+ // prefix all commands with '+'.
+ if (cmIsOn(job_server_aware) &&
+ mf.GetGlobalGenerator()->IsGNUMakeJobServerAware()) {
+ for (auto& commandLine : commandLines) {
+ commandLine.insert(commandLine.begin(), "+");
+ }
+ }
+
// Choose which mode of the command to use.
auto cc = cm::make_unique<cmCustomCommand>();
cc->SetByproducts(byproducts);
diff --git a/Source/cmAddCustomTargetCommand.cxx b/Source/cmAddCustomTargetCommand.cxx
index a246d06..6339062 100644
--- a/Source/cmAddCustomTargetCommand.cxx
+++ b/Source/cmAddCustomTargetCommand.cxx
@@ -17,6 +17,7 @@
#include "cmStringAlgorithms.h"
#include "cmSystemTools.h"
#include "cmTarget.h"
+#include "cmValue.h"
bool cmAddCustomTargetCommand(std::vector<std::string> const& args,
cmExecutionStatus& status)
@@ -54,6 +55,7 @@ bool cmAddCustomTargetCommand(std::vector<std::string> const& args,
const char* comment = nullptr;
std::vector<std::string> sources;
std::string job_pool;
+ std::string JOB_SERVER_AWARE;
// Keep track of parser state.
enum tdoing
@@ -65,6 +67,7 @@ bool cmAddCustomTargetCommand(std::vector<std::string> const& args,
doing_comment,
doing_source,
doing_job_pool,
+ doing_JOB_SERVER_AWARE,
doing_nothing
};
tdoing doing = doing_command;
@@ -102,6 +105,8 @@ bool cmAddCustomTargetCommand(std::vector<std::string> const& args,
doing = doing_comment;
} else if (copy == "JOB_POOL") {
doing = doing_job_pool;
+ } else if (copy == "JOB_SERVER_AWARE") {
+ doing = doing_JOB_SERVER_AWARE;
} else if (copy == "COMMAND") {
doing = doing_command;
@@ -148,6 +153,9 @@ bool cmAddCustomTargetCommand(std::vector<std::string> const& args,
case doing_job_pool:
job_pool = copy;
break;
+ case doing_JOB_SERVER_AWARE:
+ JOB_SERVER_AWARE = copy;
+ break;
default:
status.SetError("Wrong syntax. Unknown type of argument.");
return false;
@@ -212,6 +220,15 @@ bool cmAddCustomTargetCommand(std::vector<std::string> const& args,
return false;
}
+ // If using a GNU Make generator and `JOB_SERVER_AWARE` is set then
+ // prefix all commands with '+'.
+ if (cmIsOn(JOB_SERVER_AWARE) &&
+ mf.GetGlobalGenerator()->IsGNUMakeJobServerAware()) {
+ for (auto& commandLine : commandLines) {
+ commandLine.insert(commandLine.begin(), "+");
+ }
+ }
+
// Add the utility target to the makefile.
auto cc = cm::make_unique<cmCustomCommand>();
cc->SetWorkingDirectory(working_directory.c_str());
diff --git a/Source/cmGlobalBorlandMakefileGenerator.h b/Source/cmGlobalBorlandMakefileGenerator.h
index 049d6ba..a2adbd0 100644
--- a/Source/cmGlobalBorlandMakefileGenerator.h
+++ b/Source/cmGlobalBorlandMakefileGenerator.h
@@ -54,6 +54,8 @@ public:
bool AllowDeleteOnError() const override { return false; }
bool CanEscapeOctothorpe() const override { return true; }
+ bool IsGNUMakeJobServerAware() const override { return false; }
+
protected:
std::vector<GeneratedMakeCommand> GenerateBuildCommand(
const std::string& makeProgram, const std::string& projectName,
diff --git a/Source/cmGlobalGenerator.h b/Source/cmGlobalGenerator.h
index 9aefaff..0e40813 100644
--- a/Source/cmGlobalGenerator.h
+++ b/Source/cmGlobalGenerator.h
@@ -161,6 +161,8 @@ public:
virtual bool CheckCxxModuleSupport() { return false; }
+ virtual bool IsGNUMakeJobServerAware() const { return false; }
+
bool Compute();
virtual void AddExtraIDETargets() {}
diff --git a/Source/cmGlobalJOMMakefileGenerator.h b/Source/cmGlobalJOMMakefileGenerator.h
index 5e74875..cd3ed33 100644
--- a/Source/cmGlobalJOMMakefileGenerator.h
+++ b/Source/cmGlobalJOMMakefileGenerator.h
@@ -47,6 +47,8 @@ public:
void EnableLanguage(std::vector<std::string> const& languages, cmMakefile*,
bool optional) override;
+ bool IsGNUMakeJobServerAware() const override { return false; }
+
protected:
std::vector<GeneratedMakeCommand> GenerateBuildCommand(
const std::string& makeProgram, const std::string& projectName,
diff --git a/Source/cmGlobalNMakeMakefileGenerator.h b/Source/cmGlobalNMakeMakefileGenerator.h
index 436ebca..167889c 100644
--- a/Source/cmGlobalNMakeMakefileGenerator.h
+++ b/Source/cmGlobalNMakeMakefileGenerator.h
@@ -53,6 +53,8 @@ public:
void EnableLanguage(std::vector<std::string> const& languages, cmMakefile*,
bool optional) override;
+ bool IsGNUMakeJobServerAware() const override { return false; }
+
protected:
std::vector<GeneratedMakeCommand> GenerateBuildCommand(
const std::string& makeProgram, const std::string& projectName,
diff --git a/Source/cmGlobalUnixMakefileGenerator3.h b/Source/cmGlobalUnixMakefileGenerator3.h
index 760679a..ee78351 100644
--- a/Source/cmGlobalUnixMakefileGenerator3.h
+++ b/Source/cmGlobalUnixMakefileGenerator3.h
@@ -120,6 +120,8 @@ public:
void Configure() override;
+ bool IsGNUMakeJobServerAware() const override { return true; }
+
/**
* Generate the all required files for building this project/tree. This
* basically creates a series of LocalGenerators for each directory and
diff --git a/Source/cmGlobalWatcomWMakeGenerator.h b/Source/cmGlobalWatcomWMakeGenerator.h
index 5579120..8b24679 100644
--- a/Source/cmGlobalWatcomWMakeGenerator.h
+++ b/Source/cmGlobalWatcomWMakeGenerator.h
@@ -53,6 +53,8 @@ public:
bool AllowNotParallel() const override { return false; }
bool AllowDeleteOnError() const override { return false; }
+ bool IsGNUMakeJobServerAware() const override { return false; }
+
protected:
std::vector<GeneratedMakeCommand> GenerateBuildCommand(
const std::string& makeProgram, const std::string& projectName,
diff --git a/Tests/RunCMake/CMakeLists.txt b/Tests/RunCMake/CMakeLists.txt
index 8baa98f..584edd7 100644
--- a/Tests/RunCMake/CMakeLists.txt
+++ b/Tests/RunCMake/CMakeLists.txt
@@ -171,8 +171,9 @@ endif()
if(NOT CMAKE_GENERATOR MATCHES "Visual Studio|Xcode")
add_RunCMake_test(CMP0065 -DCMAKE_SYSTEM_NAME=${CMAKE_SYSTEM_NAME})
endif()
+add_executable(detect_jobserver detect_jobserver.c)
if(CMAKE_GENERATOR MATCHES "Make")
- add_RunCMake_test(Make -DMAKE_IS_GNU=${MAKE_IS_GNU})
+ add_RunCMake_test(Make -DMAKE_IS_GNU=${MAKE_IS_GNU} -DDETECT_JOBSERVER=$<TARGET_FILE:detect_jobserver>)
endif()
unset(ninja_test_with_qt_version)
unset(ninja_qt_args)
diff --git a/Tests/RunCMake/Make/DetectJobServer-absent-parallel-build-stderr.txt b/Tests/RunCMake/Make/DetectJobServer-absent-parallel-build-stderr.txt
new file mode 100644
index 0000000..c63bde3
--- /dev/null
+++ b/Tests/RunCMake/Make/DetectJobServer-absent-parallel-build-stderr.txt
@@ -0,0 +1 @@
+^(Warning: (Borland's make|NMake|Watcom's WMake) does not support parallel builds\. Ignoring parallel build command line option\.)?$
diff --git a/Tests/RunCMake/Make/DetectJobServer-absent.cmake b/Tests/RunCMake/Make/DetectJobServer-absent.cmake
new file mode 100644
index 0000000..e3dddc0
--- /dev/null
+++ b/Tests/RunCMake/Make/DetectJobServer-absent.cmake
@@ -0,0 +1,13 @@
+# Verifies that the jobserver connection is absent
+add_custom_command(OUTPUT custom_command.txt
+ JOB_SERVER_AWARE OFF
+ COMMENT "Should not detect jobserver"
+ COMMAND ${DETECT_JOBSERVER} --absent "custom_command.txt"
+)
+
+# trigger the custom command to run
+add_custom_target(dummy ALL
+ JOB_SERVER_AWARE OFF
+ DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/custom_command.txt
+ COMMAND ${DETECT_JOBSERVER} --absent "custom_target.txt"
+)
diff --git a/Tests/RunCMake/Make/DetectJobServer-present.cmake b/Tests/RunCMake/Make/DetectJobServer-present.cmake
new file mode 100644
index 0000000..a33658f
--- /dev/null
+++ b/Tests/RunCMake/Make/DetectJobServer-present.cmake
@@ -0,0 +1,13 @@
+# Verifies that the jobserver is present
+add_custom_command(OUTPUT custom_command.txt
+ JOB_SERVER_AWARE ON
+ COMMENT "Should detect jobserver support"
+ COMMAND ${DETECT_JOBSERVER} --present "custom_command.txt"
+)
+
+# trigger the custom command to run
+add_custom_target(dummy ALL
+ JOB_SERVER_AWARE ON
+ DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/custom_command.txt
+ COMMAND ${DETECT_JOBSERVER} --present "custom_target.txt"
+)
diff --git a/Tests/RunCMake/Make/GNUMakeJobServerAware-check.cmake b/Tests/RunCMake/Make/GNUMakeJobServerAware-check.cmake
new file mode 100644
index 0000000..7c5c296
--- /dev/null
+++ b/Tests/RunCMake/Make/GNUMakeJobServerAware-check.cmake
@@ -0,0 +1,12 @@
+# This test verifies that the commands in the generated Makefiles contain the
+# `+` prefix
+function(check_for_plus_prefix target)
+ set(file "${RunCMake_BINARY_DIR}/GNUMakeJobServerAware-build/${target}")
+ file(READ "${file}" build_file)
+ if(NOT "${build_file}" MATCHES [[\+]])
+ message(FATAL_ERROR "The file ${file} does not contain the expected prefix in the custom command.")
+ endif()
+endfunction()
+
+check_for_plus_prefix("CMakeFiles/dummy.dir/build.make")
+check_for_plus_prefix("CMakeFiles/dummy2.dir/build.make")
diff --git a/Tests/RunCMake/Make/GNUMakeJobServerAware.cmake b/Tests/RunCMake/Make/GNUMakeJobServerAware.cmake
new file mode 100644
index 0000000..951c2d7
--- /dev/null
+++ b/Tests/RunCMake/Make/GNUMakeJobServerAware.cmake
@@ -0,0 +1,12 @@
+add_custom_command(
+ OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/custom-command"
+ JOB_SERVER_AWARE ON
+ COMMAND $(CMAKE_COMMAND) -E touch "${CMAKE_CURRENT_BINARY_DIR}/custom-command"
+)
+add_custom_target(dummy ALL DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/custom-command")
+
+add_custom_target(
+ dummy2 ALL
+ JOB_SERVER_AWARE ON
+ COMMAND ${CMAKE_COMMAND} -E true
+)
diff --git a/Tests/RunCMake/Make/RunCMakeTest.cmake b/Tests/RunCMake/Make/RunCMakeTest.cmake
index c7717ec..12904c8 100644
--- a/Tests/RunCMake/Make/RunCMakeTest.cmake
+++ b/Tests/RunCMake/Make/RunCMakeTest.cmake
@@ -70,3 +70,43 @@ if(NOT RunCMake_GENERATOR STREQUAL "Watcom WMake")
run_CMP0113(OLD)
run_CMP0113(NEW)
endif()
+
+function(detect_jobserver_present is_parallel)
+ set(RunCMake_TEST_BINARY_DIR ${RunCMake_BINARY_DIR}/DetectJobServer-present-build)
+ set(RunCMake_TEST_NO_CLEAN 1)
+ set(RunCMake_TEST_OPTIONS "-DDETECT_JOBSERVER=${DETECT_JOBSERVER}")
+ run_cmake(DetectJobServer-present)
+ if (is_parallel)
+ run_cmake_command(DetectJobServer-present-parallel-build ${CMAKE_COMMAND} --build . -j4)
+ else()
+ run_cmake_command(DetectJobServer-present-build ${CMAKE_COMMAND} --build .)
+ endif()
+endfunction()
+
+function(detect_jobserver_absent is_parallel)
+ set(RunCMake_TEST_BINARY_DIR ${RunCMake_BINARY_DIR}/DetectJobServer-absent-build)
+ set(RunCMake_TEST_NO_CLEAN 1)
+ set(RunCMake_TEST_OPTIONS "-DDETECT_JOBSERVER=${DETECT_JOBSERVER}")
+ run_cmake(DetectJobServer-absent)
+ if (is_parallel)
+ run_cmake_command(DetectJobServer-absent-parallel-build ${CMAKE_COMMAND} --build . -j4)
+ else()
+ run_cmake_command(DetectJobServer-absent-build ${CMAKE_COMMAND} --build .)
+ endif()
+endfunction()
+
+# Jobservers are currently only supported by GNU makes, except MSYS2 make
+if(MAKE_IS_GNU AND NOT RunCMake_GENERATOR MATCHES "MSYS Makefiles")
+ detect_jobserver_present(ON)
+else()
+ detect_jobserver_absent(ON)
+endif()
+# No matter which generator is used, the jobserver should not be present if a
+# parallel build is not requested
+detect_jobserver_absent(OFF)
+
+if(MAKE_IS_GNU)
+ # In GNU makes, `JOB_SERVER_AWARE` support is implemented by prefixing
+ # commands with the '+' operator.
+ run_cmake(GNUMakeJobServerAware)
+endif()
diff --git a/Tests/RunCMake/detect_jobserver.c b/Tests/RunCMake/detect_jobserver.c
new file mode 100644
index 0000000..a6c1a7c
--- /dev/null
+++ b/Tests/RunCMake/detect_jobserver.c
@@ -0,0 +1,204 @@
+#ifndef _CRT_SECURE_NO_WARNINGS
+# define _CRT_SECURE_NO_WARNINGS
+#endif
+
+#if defined(_MSC_VER) && _MSC_VER >= 1928
+# pragma warning(disable : 5105) /* macro expansion warning in windows.h */
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define MAX_MESSAGE_LENGTH 1023
+#define USAGE "Usage: %s [--present|--absent] <output_file>\n"
+
+// Extracts --jobserver-auth=<string> or --jobserver-fds=<string> from
+// MAKEFLAGS. The returned pointer points to the start of <string> Returns NULL
+// if MAKEFLAGS is not set or does not contain --jobserver-auth or
+// --jobserver-fds
+char* jobserver_auth(char* message)
+{
+ const char* jobserver_auth = "--jobserver-auth=";
+ const char* jobserver_fds = "--jobserver-fds=";
+ char* auth;
+ char* fds;
+ char* start;
+ char* end;
+ char* result;
+ size_t len;
+
+ char* makeflags = getenv("MAKEFLAGS");
+ if (makeflags == NULL) {
+ strncpy(message, "MAKEFLAGS not set", MAX_MESSAGE_LENGTH);
+ return NULL;
+ }
+
+ // write MAKEFLAGS to stdout for debugging
+ fprintf(stdout, "MAKEFLAGS: %s\n", makeflags);
+
+ auth = strstr(makeflags, jobserver_auth);
+ fds = strstr(makeflags, jobserver_fds);
+ if (auth == NULL && fds == NULL) {
+ strncpy(message, "No jobserver found", MAX_MESSAGE_LENGTH);
+ return NULL;
+ } else if (auth != NULL) {
+ start = auth + strlen(jobserver_auth);
+ } else {
+ start = fds + strlen(jobserver_fds);
+ }
+
+ end = strchr(start, ' ');
+ if (end == NULL) {
+ end = start + strlen(start);
+ }
+ len = (size_t)(end - start);
+ result = (char*)malloc(len + 1);
+ strncpy(result, start, len);
+ result[len] = '\0';
+
+ return result;
+}
+
+#if defined(_WIN32)
+# include <windows.h>
+
+int windows_semaphore(const char* semaphore, char* message)
+{
+ // Open the semaphore
+ HANDLE hSemaphore = OpenSemaphoreA(SEMAPHORE_ALL_ACCESS, FALSE, semaphore);
+
+ if (hSemaphore == NULL) {
+# if defined(_MSC_VER) && _MSC_VER < 1900
+ sprintf(message, "Error opening semaphore: %s (%ld)\n", semaphore,
+ GetLastError());
+# else
+ snprintf(message, MAX_MESSAGE_LENGTH,
+ "Error opening semaphore: %s (%ld)\n", semaphore, GetLastError());
+# endif
+ return 1;
+ }
+
+ strncpy(message, "Success", MAX_MESSAGE_LENGTH);
+ return 0;
+}
+#else
+# include <errno.h>
+# include <fcntl.h>
+
+int test_fd(int read_fd, int write_fd, char* message)
+{
+ // Detect if the file descriptors are valid
+ int read_good = fcntl(read_fd, F_GETFD) != -1;
+ int read_error = errno;
+
+ int write_good = fcntl(write_fd, F_GETFD) != -1;
+ int write_error = errno;
+
+ if (!read_good || !write_good) {
+ snprintf(message, MAX_MESSAGE_LENGTH,
+ "Error opening file descriptors: %d (%s), %d (%s)\n", read_fd,
+ strerror(read_error), write_fd, strerror(write_error));
+ return 1;
+ }
+
+ snprintf(message, MAX_MESSAGE_LENGTH, "Success\n");
+ return 0;
+}
+
+int posix(const char* jobserver, char* message)
+{
+ int read_fd;
+ int write_fd;
+ const char* path;
+
+ // First try to parse as "R,W" file descriptors
+ if (sscanf(jobserver, "%d,%d", &read_fd, &write_fd) == 2) {
+ return test_fd(read_fd, write_fd, message);
+ }
+
+ // Then try to parse as "fifo:PATH"
+ if (strncmp(jobserver, "fifo:", 5) == 0) {
+ path = jobserver + 5;
+ read_fd = open(path, O_RDONLY);
+ write_fd = open(path, O_WRONLY);
+ return test_fd(read_fd, write_fd, message);
+ }
+
+ // We don't understand the format
+ snprintf(message, MAX_MESSAGE_LENGTH, "Unrecognized jobserver format: %s\n",
+ jobserver);
+ return 1;
+}
+#endif
+
+// Takes 2 arguments:
+// Either --present or --absent to indicate we expect the jobserver to be
+// "present and valid", or "absent or invalid"
+//
+// if `--present` is passed, the exit code will be 0 if the jobserver is
+// present, 1 if it is absent if `--absent` is passed, the exit code will be 0
+// if the jobserver is absent, 1 if it is present in either case, if there is
+// some fatal error (e.g the output file cannot be opened), the exit code will
+// be 2
+int main(int argc, char** argv)
+{
+ char message[MAX_MESSAGE_LENGTH + 1];
+ char* output_file;
+ FILE* fp;
+ int expecting_present;
+ int expecting_absent;
+ char* jobserver;
+ int result;
+
+ if (argc != 3) {
+ fprintf(stderr, USAGE, argv[0]);
+ return 2;
+ }
+
+ expecting_present = strcmp(argv[1], "--present") == 0;
+ expecting_absent = strcmp(argv[1], "--absent") == 0;
+ if (!expecting_present && !expecting_absent) {
+ fprintf(stderr, USAGE, argv[0]);
+ return 2;
+ }
+
+ output_file = argv[2];
+ fp = fopen(output_file, "w");
+ if (fp == NULL) {
+ fprintf(stderr, "Error opening output file: %s\n", output_file);
+ return 2;
+ }
+
+ jobserver = jobserver_auth(message);
+ if (jobserver == NULL) {
+ if (expecting_absent) {
+ fprintf(stdout, "Success\n");
+ return 0;
+ }
+
+ fprintf(stderr, "%s\n", message);
+ return 1;
+ }
+
+#if defined(_WIN32)
+ result = windows_semaphore(jobserver, message);
+#else
+ result = posix(jobserver, message);
+#endif
+ free(jobserver);
+ message[MAX_MESSAGE_LENGTH] = 0;
+
+ if (result == 0 && expecting_present) {
+ fprintf(stdout, "Success\n");
+ return 0;
+ }
+
+ if (result == 1 && expecting_absent) {
+ fprintf(stdout, "Success\n");
+ return 0;
+ }
+
+ fprintf(stderr, "%s\n", message);
+ return 1;
+}