check_by_ssh: Implement modern output functionality

2 files changed, 152 insertions, 53 deletions

diff --git a/plugins/check_by_ssh.c b/plugins/check_by_ssh.c
index a43c0d34..ad385fbd 100644
--- a/plugins/check_by_ssh.c
+++ b/plugins/check_by_ssh.c
@@ -26,16 +26,17 @@
  *
  *****************************************************************************/
 
-const char *progname = "check_by_ssh";
-const char *copyright = "2000-2024";
-const char *email = "devel@monitoring-plugins.org";
-
 #include "common.h"
+#include "output.h"
 #include "utils.h"
 #include "utils_cmd.h"
 #include "check_by_ssh.d/config.h"
 #include "states.h"
 
+const char *progname = "check_by_ssh";
+const char *copyright = "2000-2024";
+const char *email = "devel@monitoring-plugins.org";
+
 #ifndef NP_MAXARGS
 #       define NP_MAXARGS 1024
 #endif
@@ -71,6 +72,10 @@ int main(int argc, char **argv) {
 
         const check_by_ssh_config config = tmp_config.config;
 
+        if (config.output_format_is_set) {
+                mp_set_format(config.output_format);
+        }
+
         /* Set signal handling and alarm timeout */
         if (signal(SIGALRM, timeout_alarm_handler) == SIG_ERR) {
                 usage_va(_("Cannot catch SIGALRM"));
@@ -85,62 +90,101 @@ int main(int argc, char **argv) {
                 }
         }
 
-        output chld_out;
-        output chld_err;
-        mp_state_enum result = cmd_run_array(config.cmd.commargv, &chld_out, &chld_err, 0);
+        cmd_run_result child_result = cmd_run_array2(config.cmd.commargv, 0);
+        mp_check overall = mp_check_init();
 
         /* SSH returns 255 if connection attempt fails; include the first line of error output */
-        if (result == 255 && config.unknown_timeout) {
-                printf(_("SSH connection failed: %s\n"),
-                           chld_err.lines > 0 ? chld_err.line[0] : "(no error output)");
-                return STATE_UNKNOWN;
+        mp_subcheck sc_ssh_execution = mp_subcheck_init();
+        if (child_result.cmd_error_code == 255 && config.unknown_timeout) {
+                xasprintf(&sc_ssh_execution.output, "SSH connection failed: %s",
+                                  child_result.stderr.lines > 0 ? child_result.stderr.line[0]
+                                                                                                : "(no error output)");
+
+                sc_ssh_execution = mp_set_subcheck_state(sc_ssh_execution, STATE_UNKNOWN);
+                mp_add_subcheck_to_check(&overall, sc_ssh_execution);
+                mp_exit(overall);
         }
+        xasprintf(&sc_ssh_execution.output, "SSH connection succeeded");
+        sc_ssh_execution = mp_set_subcheck_state(sc_ssh_execution, STATE_OK);
+        mp_add_subcheck_to_check(&overall, sc_ssh_execution);
 
         if (verbose) {
-                for (size_t i = 0; i < chld_out.lines; i++) {
-                        printf("stdout: %s\n", chld_out.line[i]);
+                for (size_t i = 0; i < child_result.stdout.lines; i++) {
+                        printf("stdout: %s\n", child_result.stdout.line[i]);
                 }
-                for (size_t i = 0; i < chld_err.lines; i++) {
-                        printf("stderr: %s\n", chld_err.line[i]);
+                for (size_t i = 0; i < child_result.stderr.lines; i++) {
+                        printf("stderr: %s\n", child_result.stderr.line[i]);
                 }
         }
 
         size_t skip_stdout = 0;
-        if (config.skip_stdout == -1) { /* --skip-stdout specified without argument */
-                skip_stdout = chld_out.lines;
+        if (config.skip_stdout) { /* --skip-stdout specified without argument */
+                skip_stdout = child_result.stdout.lines;
         } else {
-                skip_stdout = config.skip_stdout;
+                skip_stdout = config.stdout_lines_to_ignore;
         }
 
         size_t skip_stderr = 0;
-        if (config.skip_stderr == -1) { /* --skip-stderr specified without argument */
-                skip_stderr = chld_err.lines;
+        if (config.skip_stderr) { /* --skip-stderr specified without argument */
+                skip_stderr = child_result.stderr.lines;
         } else {
-                skip_stderr = config.skip_stderr;
+                skip_stderr = config.sterr_lines_to_ignore;
         }
 
         /* Allow UNKNOWN or WARNING state for (non-skipped) output found on stderr */
-        if (chld_err.lines > (size_t)skip_stderr && (config.unknown_on_stderr || config.warn_on_stderr)) {
-                printf(_("Remote command execution failed: %s\n"), chld_err.line[skip_stderr]);
+        if (child_result.stderr.lines > skip_stderr &&
+                (config.unknown_on_stderr || config.warn_on_stderr)) {
+                mp_subcheck sc_stderr = mp_subcheck_init();
+                xasprintf(&sc_stderr.output, "remote command execution failed: %s",
+                                  child_result.stderr.line[skip_stderr]);
+
                 if (config.unknown_on_stderr) {
-                        return max_state_alt(result, STATE_UNKNOWN);
-                } else if (config.warn_on_stderr) {
-                        return max_state_alt(result, STATE_WARNING);
+                        sc_stderr = mp_set_subcheck_state(sc_stderr, STATE_UNKNOWN);
+                }
+
+                if (config.warn_on_stderr) {
+                        sc_stderr = mp_set_subcheck_state(sc_stderr, STATE_WARNING);
                 }
+
+                mp_add_subcheck_to_check(&overall, sc_stderr);
+                // TODO still exit here?
         }
 
         /* this is simple if we're not supposed to be passive.
          * Wrap up quickly and keep the tricks below */
         if (!config.passive) {
-                if (chld_out.lines > (size_t)skip_stdout) {
-                        for (size_t i = skip_stdout; i < chld_out.lines; i++) {
-                                puts(chld_out.line[i]);
+                mp_subcheck sc_active_check = mp_subcheck_init();
+                xasprintf(&sc_active_check.output, "command stdout:");
+
+                if (child_result.stdout.lines > skip_stdout) {
+                        for (size_t i = skip_stdout; i < child_result.stdout.lines; i++) {
+                                xasprintf(&sc_active_check.output, "%s\n%s", sc_active_check.output,
+                                                  child_result.stdout.line[i]);
                         }
                 } else {
-                        printf(_("%s - check_by_ssh: Remote command '%s' returned status %d\n"),
-                                   state_text(result), config.remotecmd, result);
+                        xasprintf(&sc_active_check.output, "remote command '%s' returned status %d",
+                                          config.remotecmd, child_result.cmd_error_code);
+                }
+
+                /* return error status from remote command */
+
+                switch (child_result.cmd_error_code) {
+                case 0:
+                        sc_active_check = mp_set_subcheck_state(sc_active_check, STATE_OK);
+                        break;
+                case 1:
+                        sc_active_check = mp_set_subcheck_state(sc_active_check, STATE_WARNING);
+                        break;
+                case 2:
+                        sc_active_check = mp_set_subcheck_state(sc_active_check, STATE_CRITICAL);
+                        break;
+                default:
+                        sc_active_check = mp_set_subcheck_state(sc_active_check, STATE_UNKNOWN);
+                        break;
                 }
-                return result; /* return error status from remote command */
+
+                mp_add_subcheck_to_check(&overall, sc_active_check);
+                mp_exit(overall);
         }
 
         /*
@@ -148,36 +192,57 @@ int main(int argc, char **argv) {
          */
 
         /* process output */
-        FILE *file_pointer = NULL;
-        if (!(file_pointer = fopen(config.outputfile, "a"))) {
-                printf(_("SSH WARNING: could not open %s\n"), config.outputfile);
-                exit(STATE_UNKNOWN);
+        mp_subcheck sc_passive_file = mp_subcheck_init();
+        FILE *output_file = NULL;
+        if (!(output_file = fopen(config.outputfile, "a"))) {
+                xasprintf(&sc_passive_file.output, "could not open %s", config.outputfile);
+                sc_passive_file = mp_set_subcheck_state(sc_passive_file, STATE_UNKNOWN);
+
+                mp_add_subcheck_to_check(&overall, sc_passive_file);
+                mp_exit(overall);
         }
 
+        xasprintf(&sc_passive_file.output, "opened output file %s", config.outputfile);
+        sc_passive_file = mp_set_subcheck_state(sc_passive_file, STATE_OK);
+        mp_add_subcheck_to_check(&overall, sc_passive_file);
+
         time_t local_time = time(NULL);
         unsigned int commands = 0;
         char *status_text;
         int cresult;
-        for (size_t i = skip_stdout; i < chld_out.lines; i++) {
-                status_text = chld_out.line[i++];
-                if (i == chld_out.lines || strstr(chld_out.line[i], "STATUS CODE: ") == NULL) {
-                        die(STATE_UNKNOWN, _("%s: Error parsing output\n"), progname);
+        mp_subcheck sc_parse_passive = mp_subcheck_init();
+        for (size_t i = skip_stdout; i < child_result.stdout.lines; i++) {
+                status_text = child_result.stdout.line[i++];
+                if (i == child_result.stdout.lines ||
+                        strstr(child_result.stdout.line[i], "STATUS CODE: ") == NULL) {
+
+                        sc_parse_passive = mp_set_subcheck_state(sc_parse_passive, STATE_UNKNOWN);
+                        xasprintf(&sc_parse_passive.output, "failed to parse output");
+                        mp_add_subcheck_to_check(&overall, sc_parse_passive);
+                        mp_exit(overall);
                 }
 
                 if (config.service[commands] && status_text &&
-                        sscanf(chld_out.line[i], "STATUS CODE: %d", &cresult) == 1) {
-                        fprintf(file_pointer, "[%d] PROCESS_SERVICE_CHECK_RESULT;%s;%s;%d;%s\n",
-                                        (int)local_time, config.host_shortname, config.service[commands++], cresult,
-                                        status_text);
+                        sscanf(child_result.stdout.line[i], "STATUS CODE: %d", &cresult) == 1) {
+                        fprintf(output_file, "[%d] PROCESS_SERVICE_CHECK_RESULT;%s;%s;%d;%s\n", (int)local_time,
+                                        config.host_shortname, config.service[commands++], cresult, status_text);
                 }
         }
 
+        sc_parse_passive = mp_set_subcheck_state(sc_parse_passive, STATE_OK);
+        xasprintf(&sc_parse_passive.output, "parsed and wrote output");
+        mp_add_subcheck_to_check(&overall, sc_parse_passive);
+
         /* Multiple commands and passive checking should always return OK */
-        exit(result);
+        mp_exit(overall);
 }
 
 /* process command-line arguments */
 check_by_ssh_config_wrapper process_arguments(int argc, char **argv) {
+        enum {
+                output_format_index = CHAR_MAX + 1,
+        };
+
         static struct option longopts[] = {
                 {"version", no_argument, 0, 'V'},
                 {"help", no_argument, 0, 'h'},
@@ -207,6 +272,7 @@ check_by_ssh_config_wrapper process_arguments(int argc, char **argv) {
                 {"ssh-option", required_argument, 0, 'o'},
                 {"quiet", no_argument, 0, 'q'},
                 {"configfile", optional_argument, 0, 'F'},
+                {"output-format", required_argument, 0, output_format_index},
                 {0, 0, 0, 0}};
 
         check_by_ssh_config_wrapper result = {
@@ -327,20 +393,27 @@ check_by_ssh_config_wrapper process_arguments(int argc, char **argv) {
                         break;
                 case 'S': /* skip n (or all) lines on stdout */
                         if (optarg == NULL) {
-                                result.config.skip_stdout = -1; /* skip all output on stdout */
+                                result.config.skip_stdout = true; /* skip all output on stdout */
+
+                                if (verbose) {
+                                        printf("Setting the skip_stdout flag\n");
+                                }
                         } else if (!is_integer(optarg)) {
                                 usage_va(_("skip-stdout argument must be an integer"));
                         } else {
-                                result.config.skip_stdout = atoi(optarg);
+                                result.config.stdout_lines_to_ignore = atoi(optarg);
                         }
                         break;
                 case 'E': /* skip n (or all) lines on stderr */
                         if (optarg == NULL) {
-                                result.config.skip_stderr = -1; /* skip all output on stderr */
+                                result.config.skip_stderr = true; /* skip all output on stderr */
+                                if (verbose) {
+                                        printf("Setting the skip_stderr flag\n");
+                                }
                         } else if (!is_integer(optarg)) {
                                 usage_va(_("skip-stderr argument must be an integer"));
                         } else {
-                                result.config.skip_stderr = atoi(optarg);
+                                result.config.sterr_lines_to_ignore = atoi(optarg);
                         }
                         break;
                 case 'e': /* exit with unknown if there is an output on stderr */
@@ -360,6 +433,18 @@ check_by_ssh_config_wrapper process_arguments(int argc, char **argv) {
                         result.config.cmd = comm_append(result.config.cmd, "-F");
                         result.config.cmd = comm_append(result.config.cmd, optarg);
                         break;
+                case output_format_index: {
+                        parsed_output_format parser = mp_parse_output_format(optarg);
+                        if (!parser.parsing_success) {
+                                // TODO List all available formats here, maybe add anothoer usage function
+                                printf("Invalid output format: %s\n", optarg);
+                                exit(STATE_UNKNOWN);
+                        }
+
+                        result.config.output_format_is_set = true;
+                        result.config.output_format = parser.output_format;
+                        break;
+                }
                 default: /* help */
                         usage5();
                 }
@@ -502,6 +587,7 @@ void print_help(void) {
         printf(" %s\n", "-U, --unknown-timeout");
         printf("    %s\n", _("Make connection problems return UNKNOWN instead of CRITICAL"));
         printf(UT_VERBOSE);
+        printf(UT_OUTPUT_FORMAT);
         printf("\n");
         printf(" %s\n", _("The most common mode of use is to refer to a local identity file with"));
         printf(" %s\n", _("the '-i' option. In this mode, the identity pair should have a null"));
diff --git a/plugins/check_by_ssh.d/config.h b/plugins/check_by_ssh.d/config.h
index 0e4b56d4..b6a57964 100644
--- a/plugins/check_by_ssh.d/config.h
+++ b/plugins/check_by_ssh.d/config.h
@@ -1,6 +1,7 @@
 #pragma once
 
 #include "../../config.h"
+#include "output.h"
 #include <stddef.h>
 
 typedef struct {
@@ -23,10 +24,16 @@ typedef struct {
         bool unknown_timeout;
         bool unknown_on_stderr;
         bool warn_on_stderr;
-        int skip_stdout;
-        int skip_stderr;
+        bool skip_stdout;
+        size_t stdout_lines_to_ignore;
+        bool skip_stderr;
+        size_t sterr_lines_to_ignore;
+
         bool passive;
         char *outputfile;
+
+        bool output_format_is_set;
+        mp_output_format output_format;
 } check_by_ssh_config;
 
 check_by_ssh_config check_by_ssh_config_init() {
@@ -49,10 +56,16 @@ check_by_ssh_config check_by_ssh_config_init() {
                 .unknown_timeout = false,
                 .unknown_on_stderr = false,
                 .warn_on_stderr = false,
-                .skip_stderr = 0,
-                .skip_stdout = 0,
+
+                .skip_stderr = false,
+                .stdout_lines_to_ignore = 0,
+                .skip_stdout = false,
+                .sterr_lines_to_ignore = 0,
+
                 .passive = false,
                 .outputfile = NULL,
+
+                .output_format_is_set = false,
         };
         return tmp;
 }