ENT-14193: Binary for agent driven cfengine

.gitignore

@@ -43,6 +43,7 @@ stamp-h1
 /cf-serverd/Makefile
 /cf-testd/Makefile
 /cf-upgrade/Makefile
+/cf-watchd/Makefile
 /contrib/vagrant-ci/centos-9s-x64/Makefile
 /examples/Makefile
 /ext/Makefile
@@ -112,6 +113,8 @@ xml_tmp_suite
 /cf-testd/cf-testd.exe
 /cf-upgrade/cf-upgrade
 /cf-upgrade/cf-upgrade.exe
+/cf-watchd/cf-watchd
+/cf-watchd/cf-watchd.exe
 /ext/rpmvercmp
 /ext/rpmvercmp.exe
 

Makefile.am

@@ -45,6 +45,7 @@ SUBDIRS = \
 	cf-upgrade \
 	cf-net \
 	cf-secret \
+	cf-watchd \
 	misc \
 	python \
 	ext \

cf-watchd/Makefile.am

@@ -0,0 +1,52 @@
+#
+#  Copyright 2021 Northern.tech AS
+#
+#  This file is part of CFEngine 3 - written and maintained by Northern.tech AS.
+#
+#  This program is free software; you can redistribute it and/or modify it
+#  under the terms of the GNU General Public License as published by the
+#  Free Software Foundation; version 3.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA
+#
+# To the extent this program is licensed as part of the Enterprise
+# versions of CFEngine, the applicable Commercial Open Source License
+# (COSL) may apply to this file if you as a licensee so wish it. See
+# included file COSL.txt.
+#
+noinst_LTLIBRARIES = libcf-watchd.la
+
+AM_CPPFLAGS = -I$(srcdir)/../libpromises -I$(srcdir)/../libntech/libutils \
+	-I$(srcdir)/../libcfecompat \
+	-I$(srcdir)/../libcfnet \
+	$(OPENSSL_CPPFLAGS) \
+	$(PCRE2_CPPFLAGS) \
+	$(ENTERPRISE_CPPFLAGS)
+
+AM_CFLAGS = @CFLAGS@ \
+	$(OPENSSL_CFLAGS) \
+	$(ENTERPRISE_CFLAGS)
+
+libcf_watchd_la_LIBADD = ../libpromises/libpromises.la
+
+libcf_watchd_la_SOURCES = cf-watchd.c
+
+if !BUILTIN_EXTENSIONS
+ bin_PROGRAMS = cf-watchd
+ cf_watchd_LDADD = libcf-watchd.la
+ cf_watchd_SOURCES =
+endif
+
+CLEANFILES = *.gcno *.gcda
+
+#
+# Some basic clean ups
+#
+MOSTLYCLEANFILES = *~ *.orig *.rej

cf-watchd/cf-watchd.c

@@ -0,0 +1,257 @@
+#include <stdio.h>
+#include <unistd.h>
+
+#include <exec_tools.h>
+#include <signals.h>
+#include <generic_agent.h>
+#include <logging.h>
+#include <eval_context.h>
+#include <cleanup.h>
+#include <man.h>
+#include <known_dirs.h>
+
+
+static GenericAgentConfig *CheckOpts(int argc, char **argv);
+static void WatchStart();
+
+/*****************************************************************************/
+/* Globals                                                                   */
+/*****************************************************************************/
+
+int NO_FORK = false;
+
+/*******************************************************************/
+/* Command line options                                            */
+/*******************************************************************/
+
+
+static const char *const CF_WATCHD_SHORT_DESCRIPTION =
+    "event watching daemon for CFEngine";
+
+static const char *const CF_WATCHD_MANPAGE_LONG_DESCRIPTION =
+    "cf-watchd is the event watching and reacting daemon for CFEngine. It watches specific events defined in the policy "
+    "and runs policy code on reaction to these events.";
+
+static const Component COMPONENT =
+{
+    .name = "cf-watchd",
+    .website = CF_WEBSITE,
+    .copyright = CF_COPYRIGHT
+};
+
+static const struct option OPTIONS[] =
+{
+    {"help", no_argument, 0, 'h'},
+    {"debug", no_argument, 0, 'd'},
+    {"verbose", no_argument, 0, 'v'},
+    {"version", no_argument, 0, 'V'},
+    {"no-lock", no_argument, 0, 'K'},
+    {"file", required_argument, 0, 'f'},
+    {"log-level", required_argument, 0, 'g'},
+    {"inform", no_argument, 0, 'I'},
+    {"no-fork", no_argument, 0, 'F'},
+    {"man", no_argument, 0, 'M'},
+    {"color", optional_argument, 0, 'C'},
+    {"timestamp", no_argument, 0, 'l'},
+    /* Only long option for the rest */
+    {"ignore-preferred-augments", no_argument, 0, 0},
+    {NULL, 0, 0, '\0'}
+};
+
+static const char *const HINTS[] =
+{
+    "Print the help message",
+    "Enable debugging output",
+    "Output verbose information about the behaviour of cf-watchd",
+    "Output the version of the software",
+    "Ignore system lock",
+    "Specify an alternative input file than the default. This option is overridden by FILE if supplied as argument.",
+    "Specify how detailed logs should be. Possible values: 'error', 'warning', 'notice', 'info', 'verbose', 'debug'",
+    "Print basic information about changes made to the system, i.e. promises repaired",
+    "Run process in foreground, not as a daemon",
+    "Outputs the man page of the program",
+    "Enable colorized output. Possible values: 'always', 'auto', 'never'. If option is used, the default value is 'auto'",
+    "Log timestamps on each line of log output",
+    "Ignore def_preferred.json file in favor of def.json",
+    NULL
+};
+
+/*****************************************************************************/
+
+int main(int argc, char **argv)
+{
+  GenericAgentConfig *config = CheckOpts(argc, argv);
+  EvalContext *ctx = EvalContextNew();
+  GenericAgentConfigApply(ctx, config);
+
+  pid_t existing_pid = ReadPID("cf-watchd.pid");
+  if ((existing_pid != -1) && (kill(existing_pid, 0) == 0))
+  {
+      Log(LOG_LEVEL_ERR, "Another instance of cf-watchd is already running, terminating");
+      return 1;
+  }
+
+#ifdef __MINGW32__
+
+  if (!NO_FORK)
+  {
+    Log(LOG_LEVEL_VERBOSE, "Windows does not support starting processes in the background - starting in foreground");
+  }
+
+#else /* !__MINGW32__ */
+
+  if ((!NO_FORK) && (fork() != 0))
+  {
+    Log(LOG_LEVEL_INFO, "cf-watchd: starting");
+    _exit(EXIT_SUCCESS);
+  }
+
+  if (!NO_FORK)
+  {
+      ActAsDaemon();
+  }
+
+#endif /* !__MINGW32__ */
+
+
+  umask(077);
+  WritePID("cf-watchd.pid");
+
+  signal(SIGINT, HandleSignalsForDaemon);
+  signal(SIGTERM, HandleSignalsForDaemon);
+  signal(SIGBUS, HandleSignalsForDaemon);
+  signal(SIGHUP, HandleSignalsForDaemon);
+  signal(SIGPIPE, SIG_IGN);
+  signal(SIGUSR1, HandleSignalsForDaemon);
+  signal(SIGUSR2, HandleSignalsForDaemon);
+
+  WatchStart();
+
+  GenericAgentFinalize(ctx, config);
+  CallCleanupFunctions();
+
+  return 0;
+}
+
+static GenericAgentConfig *CheckOpts(int argc, char **argv)
+{
+    extern char *optarg;
+    int c;
+    GenericAgentConfig *config = GenericAgentConfigNewDefault(AGENT_TYPE_WATCH, GetTTYInteractive());
+
+    int longopt_idx;
+    while ((c = getopt_long(argc, argv, "dvIf:g:VKMFhC::l",
+                            OPTIONS, &longopt_idx)) != -1)
+    {
+        switch (c)
+        {
+        case 'f':
+            GenericAgentConfigSetInputFile(config, GetInputDir(), optarg);
+            MINUSF = true;
+            break;
+
+        case 'd':
+            LogSetGlobalLevel(LOG_LEVEL_DEBUG);
+            NO_FORK = true;
+            break;
+
+        case 'K':
+            config->ignore_locks = true;
+            break;
+
+        case 'I':
+            LogSetGlobalLevel(LOG_LEVEL_INFO);
+            break;
+
+        case 'v':
+            LogSetGlobalLevel(LOG_LEVEL_VERBOSE);
+            NO_FORK = true;
+            break;
+
+        case 'g':
+            LogSetGlobalLevelArgOrExit(optarg);
+            break;
+
+        case 'F':
+            NO_FORK = true;
+            break;
+
+        case 'V':
+        {
+            Writer *w = FileWriter(stdout);
+            GenericAgentWriteVersion(w);
+            FileWriterDetach(w);
+        }
+        DoCleanupAndExit(EXIT_SUCCESS);
+
+        case 'h':
+        {
+            Writer *w = FileWriter(stdout);
+            WriterWriteHelp(w, &COMPONENT, OPTIONS, HINTS, NULL, false, true);
+            FileWriterDetach(w);
+        }
+        DoCleanupAndExit(EXIT_SUCCESS);
+
+        case 'M':
+        {
+            Writer *out = FileWriter(stdout);
+            ManPageWrite(out, "cf-watchd", time(NULL),
+                         CF_WATCHD_SHORT_DESCRIPTION,
+                         CF_WATCHD_MANPAGE_LONG_DESCRIPTION,
+                         OPTIONS, HINTS,
+                         NULL, false,
+                         true);
+            FileWriterDetach(out);
+            DoCleanupAndExit(EXIT_SUCCESS);
+        }
+
+        case 'C':
+            if (!GenericAgentConfigParseColor(config, optarg))
+            {
+                DoCleanupAndExit(EXIT_FAILURE);
+            }
+            break;
+
+        case 'l':
+            LoggingEnableTimestamps(true);
+            break;
+
+        /* long options only */
+        case 0:
+        {
+            const char *const option_name = OPTIONS[longopt_idx].name;
+            if (StringEqual(option_name, "ignore-preferred-augments"))
+            {
+                config->ignore_preferred_augments = true;
+            }
+            break;
+        }
+
+        default:
+        {
+            Writer *w = FileWriter(stdout);
+            WriterWriteHelp(w, &COMPONENT, OPTIONS, HINTS, NULL, false, true);
+            FileWriterDetach(w);
+        }
+        DoCleanupAndExit(EXIT_FAILURE);
+        }
+    }
+
+    if (!GenericAgentConfigParseArguments(config, argc - optind, argv + optind))
+    {
+        Log(LOG_LEVEL_ERR, "Too many arguments");
+        DoCleanupAndExit(EXIT_FAILURE);
+    }
+
+    return config;
+}
+
+static void WatchStart()
+{
+  for (int i = 0; !IsPendingTermination(); i++)
+  {
+    /* Do something */
+    Log(LOG_LEVEL_INFO, "cf-watchd: %d", i);
+    sleep(1);
+  }
+}

configure.ac

@@ -2005,6 +2005,7 @@ AC_CONFIG_FILES([Makefile
     cf-testd/Makefile
     cf-net/Makefile
     cf-secret/Makefile
+    cf-watchd/Makefile
     config.post.h
     contrib/vagrant-ci/centos-9s-x64/Makefile
     misc/Makefile

libpromises/cf3.defs.h

@@ -398,6 +398,7 @@ typedef enum
 #define CF_RUNC     "runagent"
 #define CF_KEYGEN   "keygenerator"
 #define CF_HUBC     "hub"
+#define CF_WATCHC   "watch"
 
 typedef enum
 {
@@ -409,6 +410,7 @@ typedef enum
     AGENT_TYPE_RUNAGENT,
     AGENT_TYPE_KEYGEN,
     AGENT_TYPE_HUB,
+    AGENT_TYPE_WATCH,
     AGENT_TYPE_NOAGENT
 } AgentType;
 

libpromises/constants.c

@@ -72,6 +72,7 @@ const char *const CF_AGENTTYPES[] =   /* see enum cfagenttype */
     CF_RUNC,
     CF_KEYGEN,
     CF_HUBC,
+    CF_WATCHC,
     "<notype>",
 };