From 7547ebbd7b7c316520259e7ca6071dc9fe8bd8aa Mon Sep 17 00:00:00 2001
From: Davin McCall <davmac@davmac.org>
Date: Mon, 23 Dec 2019 12:57:49 +1000
Subject: [PATCH] Add SHUTDOWN_PREFIX build variable, controls name of shutdown
 executable

Useful for installing Dinit alongside eg Sys V init.
---
 BUILD.txt          | 15 ++++++++++++++-
 src/Makefile       | 12 ++++++------
 src/dinit.cc       |  2 +-
 src/mconfig-gen.cc |  1 +
 4 files changed, 22 insertions(+), 8 deletions(-)

diff --git a/BUILD.txt b/BUILD.txt
index 43d5fb3..7d656b0 100644
--- a/BUILD.txt
+++ b/BUILD.txt
@@ -63,7 +63,12 @@ SYSCONTROLSOCKET=...
 BUILD_SHUTDOWN=yes|no
     Whether to build the "shutdown" (and "halt" etc) utilities. These are only useful
     if dinit is the system init (i.e. the PID 1 process). You probably don't want this
-    unless building for Linux. 
+    unless building for Linux.
+SHUTDOWN_PREFIX=...
+    Name prefix for "shutdown", "halt" and "reboot" commands (if they are built). This affects
+    both the output, and what command dinit will execute as part of system shutdown.
+    If you want to install Dinit alongside another init system with its own shutdown/halt/reboot
+    commands, set this (for eg. to "dinit-").
 USE_UTMPX=1|0
     Whether to build support for manipulating the utmp/utmpx database via the related POSIX
     functions. If not set to any value, support is enabled for certain systems automatically
@@ -72,6 +77,7 @@ SANITIZE_OPTS=...
     Any options to enable run-time sanitizers or additional safety checks. This will be used
     only when building tests. It can safely be left blank.
 
+
 Running test suite
 =-=-=-=-=-=-=-=-=-
 
@@ -96,6 +102,13 @@ If you get this, either disable the address sanitizer or make sure you have over
 
 Any test failures will abort the test suite run immediately.
 
+To run the integration tests:
+
+    make check-igr
+    
+(The integration tests are more fragile than the unit tests, but give a better indication that
+Dinit will actually work correctly on your system).
+
 In addition to the standard test suite, there is experimental support for fuzzing the control
 protocol handling using LLVM/clang's fuzzer (libFuzzer). Change to the `src/tests/cptests`
 directory and build the "fuzz" target:
diff --git a/src/Makefile b/src/Makefile
index 88ecb15..c9910eb 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -6,7 +6,7 @@ HOSTLDFLAGS ?= $(LDFLAGS)
 STRIPOPTS ?= -s
 
 ifeq ($(BUILD_SHUTDOWN),yes)
-  SHUTDOWN=shutdown
+  SHUTDOWN=$(SHUTDOWN_PREFIX)shutdown
 endif
 
 dinit_objects = dinit.o load-service.o service.o proc-service.o baseproc-service.o control.o dinit-log.o \
@@ -27,7 +27,7 @@ all: dinit dinitctl dinitcheck $(SHUTDOWN)
 	fi
 
 includes/mconfig.h: mconfig-gen
-	./mconfig-gen SBINDIR=$(SBINDIR) SYSCONTROLSOCKET=$(SYSCONTROLSOCKET) \
+	./mconfig-gen SBINDIR=$(SBINDIR) SYSCONTROLSOCKET=$(SYSCONTROLSOCKET) SHUTDOWN_PREFIX=$(SHUTDOWN_PREFIX) \
 		$(if $(USE_UTMPX),USE_UTMPX=$(USE_UTMPX),) > includes/mconfig.h
 
 mconfig-gen: mconfig-gen.cc ../mconfig
@@ -44,8 +44,8 @@ dinitctl: dinitctl.o
 dinitcheck: dinitcheck.o options-processing.o
 	$(CXX) -o dinitcheck dinitcheck.o options-processing.o $(LDFLAGS)
 
-shutdown: shutdown.o
-	$(CXX) -o shutdown shutdown.o $(LDFLAGS)
+$(SHUTDOWNPREFIX)shutdown: shutdown.o
+	$(CXX) -o $(SHUTDOWNPREFIX)shutdown shutdown.o $(LDFLAGS)
 
 $(objects): %.o: %.cc
 	$(CXX) $(CXXOPTS) -MMD -MP -Iincludes -Idasynq -c $< -o $@
@@ -63,8 +63,8 @@ install: all
 	install -d $(DESTDIR)$(SBINDIR)
 	install $(STRIPOPTS) dinit dinitctl dinitcheck $(SHUTDOWN) $(DESTDIR)$(SBINDIR)
 ifeq ($(BUILD_SHUTDOWN),yes)
-	ln -f $(DESTDIR)$(SBINDIR)/shutdown $(DESTDIR)$(SBINDIR)/halt
-	ln -f $(DESTDIR)$(SBINDIR)/shutdown $(DESTDIR)$(SBINDIR)/reboot
+	ln -f $(DESTDIR)$(SBINDIR)/$(SHUTDOWN) $(DESTDIR)$(SBINDIR)/$(SHUTDOWNPREFIX)halt
+	ln -f $(DESTDIR)$(SBINDIR)/$(SHUTDOWN) $(DESTDIR)$(SBINDIR)/$(SHUTDOWNPREFIX)reboot
 endif
 
 clean:
diff --git a/src/dinit.cc b/src/dinit.cc
index a5a7cd4..1c78278 100644
--- a/src/dinit.cc
+++ b/src/dinit.cc
@@ -174,7 +174,7 @@ namespace {
     log_flush_timer_t log_flush_timer;
 
     // These need to be at namespace scope to prevent causing stack allocations when using them:
-    constexpr auto shutdown_exec = literal(SBINDIR) + "/" + "shutdown";
+    constexpr auto shutdown_exec = literal(SBINDIR) + "/" + SHUTDOWN_PREFIX + "shutdown";
     constexpr auto error_exec_sd = literal("Error executing ") + shutdown_exec + ": ";
 }
 
diff --git a/src/mconfig-gen.cc b/src/mconfig-gen.cc
index 4ab7075..3b6af17 100644
--- a/src/mconfig-gen.cc
+++ b/src/mconfig-gen.cc
@@ -71,6 +71,7 @@ int main(int argc, char **argv)
     cout << "\n// Constants\n";
     cout << "constexpr static char SYSCONTROLSOCKET[] = " << stringify(vars["SYSCONTROLSOCKET"]) << ";\n";
     cout << "constexpr static char SBINDIR[] = " << stringify(vars["SBINDIR"]) << ";\n";
+    cout << "constexpr static char SHUTDOWN_PREFIX[] = " << stringify(vars["SHUTDOWN_PREFIX"]) << ";\n";
 
     cout << "\n#endif\n";
     return 0;
-- 
2.25.1