Re: [Qemu-devel] [PATCH v2 06/12] qga: move option parsing to seperate function

[Michael Roth <mdroth@linux.vnet.ibm.com>]

Quoting marcandre.lureau@redhat.com (2015-08-25 17:10:18)
> From: Marc-André Lureau <marcandre.lureau@redhat.com>
> 
> Move option parsing out of giant main().
> 
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>

Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>

> ---
>  qga/main.c | 165 +++++++++++++++++++++++++++++++++++--------------------------
>  1 file changed, 96 insertions(+), 69 deletions(-)
> 
> diff --git a/qga/main.c b/qga/main.c
> index 83b7804..a8dda38 100644
> --- a/qga/main.c
> +++ b/qga/main.c
> @@ -941,19 +941,28 @@ static GList *split_list(gchar *str, const gchar separator)
>      return list;
>  }
> 
> -int main(int argc, char **argv)
> -{
> -    const char *sopt = "hVvdm:p:l:f:F::b:s:t:";
> -    char *method = NULL, *channel_path = NULL;
> -    char *log_filepath = NULL;
> -    char *pid_filepath = NULL;
> +typedef struct GAConfig {
> +    char *channel_path;
> +    char *method;
> +    char *log_filepath;
> +    char *pid_filepath;
>  #ifdef CONFIG_FSFREEZE
> -    char *fsfreeze_hook = NULL;
> +    char *fsfreeze_hook;
>  #endif
> -    char *state_dir = NULL;
> +    char *state_dir;
>  #ifdef _WIN32
> -    const char *service = NULL;
> +    const char *service;
>  #endif
> +    GList *blacklist;
> +    int daemonize;
> +    GLogLevelFlags log_level;
> +} GAConfig;
> +
> +static GAConfig *config_parse(int argc, char **argv)
> +{
> +    GAConfig *config = g_new0(GAConfig, 1);
> +    const char *sopt = "hVvdm:p:l:f:F::b:s:t:D";
> +    int opt_ind = 0, ch;
>      const struct option lopt[] = {
>          { "help", 0, NULL, 'h' },
>          { "version", 0, NULL, 'V' },
> @@ -973,74 +982,71 @@ int main(int argc, char **argv)
>          { "statedir", 1, NULL, 't' },
>          { NULL, 0, NULL, 0 }
>      };
> -    int opt_ind = 0, ch, daemonize = 0;
> -    GLogLevelFlags log_level = G_LOG_LEVEL_ERROR | G_LOG_LEVEL_CRITICAL;
> -    GList *blacklist = NULL;
> -    GAState *s;
> 
> -    module_call_init(MODULE_INIT_QAPI);
> +    config->log_level = G_LOG_LEVEL_ERROR | G_LOG_LEVEL_CRITICAL;
> 
> -    init_dfl_pathnames();
>      while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
>          switch (ch) {
>          case 'm':
> -            method = g_strdup(optarg);
> +            config->method = g_strdup(optarg);
>              break;
>          case 'p':
> -            channel_path = g_strdup(optarg);
> +            config->channel_path = g_strdup(optarg);
>              break;
>          case 'l':
> -            log_filepath = g_strdup(optarg);
> +            config->log_filepath = g_strdup(optarg);
>              break;
>          case 'f':
> -            pid_filepath = g_strdup(optarg);
> +            config->pid_filepath = g_strdup(optarg);
>              break;
>  #ifdef CONFIG_FSFREEZE
>          case 'F':
> -            fsfreeze_hook = g_strdup(optarg ?: QGA_FSFREEZE_HOOK_DEFAULT);
> +            config->fsfreeze_hook = g_strdup(optarg ?: QGA_FSFREEZE_HOOK_DEFAULT);
>              break;
>  #endif
>          case 't':
> -            state_dir = g_strdup(optarg);
> +            config->state_dir = g_strdup(optarg);
>              break;
>          case 'v':
>              /* enable all log levels */
> -            log_level = G_LOG_LEVEL_MASK;
> +            config->log_level = G_LOG_LEVEL_MASK;
>              break;
>          case 'V':
>              printf("QEMU Guest Agent %s\n", QEMU_VERSION);
>              exit(EXIT_SUCCESS);
>          case 'd':
> -            daemonize = 1;
> +            config->daemonize = 1;
>              break;
>          case 'b': {
>              if (is_help_option(optarg)) {
>                  qmp_for_each_command(ga_print_cmd, NULL);
>                  exit(EXIT_SUCCESS);
>              }
> -            blacklist = g_list_concat(blacklist, split_list(optarg, ','));
> +            config->blacklist = g_list_concat(config->blacklist,
> +                                             split_list(optarg, ','));
>              break;
>          }
>  #ifdef _WIN32
>          case 's':
> -            service = optarg;
> -            if (strcmp(service, "install") == 0) {
> +            config->service = optarg;
> +            if (strcmp(config->service, "install") == 0) {
>                  if (ga_install_vss_provider()) {
>                      exit(EXIT_FAILURE);
>                  }
> -                if (ga_install_service(channel_path, log_filepath, state_dir)) {
> +                if (ga_install_service(config->channel_path,
> +                                       config->log_filepath, config->state_dir)) {
>                      exit(EXIT_FAILURE);
>                  }
>                  exit(EXIT_SUCCESS);
> -            } else if (strcmp(service, "uninstall") == 0) {
> +            } else if (strcmp(config->service, "uninstall") == 0) {
>                  ga_uninstall_vss_provider();
>                  exit(ga_uninstall_service());
> -            } else if (strcmp(service, "vss-install") == 0) {
> +            } else if (strcmp(config->service, "vss-install") == 0) {
>                  if (ga_install_vss_provider()) {
>                      exit(EXIT_FAILURE);
>                  }
>                  exit(EXIT_SUCCESS);
> -            } else if (strcmp(service, "vss-uninstall") == 0) {
> +            } else if (strcmp(config->service, "vss-uninstall") == 0) {
>                  ga_uninstall_vss_provider();
>                  exit(EXIT_SUCCESS);
>              } else {
> @@ -1059,12 +1065,39 @@ int main(int argc, char **argv)
>          }
>      }
> 
> -    if (pid_filepath == NULL) {
> -        pid_filepath = g_strdup(dfl_pathnames.pidfile);
> +    return config;
> +}
> +
> +static void config_free(GAConfig *config)
> +{
> +    g_free(config->method);
> +    g_free(config->log_filepath);
> +    g_free(config->pid_filepath);
> +    g_free(config->state_dir);
> +    g_free(config->channel_path);
> +#ifdef CONFIG_FSFREEZE
> +    g_free(config->fsfreeze_hook);
> +#endif
> +    g_free(config);
> +}
> +
> + int main(int argc, char **argv)
> +{
> +    GAState *s;
> +    GAConfig *config;
> +
> +    module_call_init(MODULE_INIT_QAPI);
> +
> +    init_dfl_pathnames();
> +
> +    config = config_parse(argc, argv);
> +
> +    if (config->pid_filepath == NULL) {
> +        config->pid_filepath = g_strdup(dfl_pathnames.pidfile);
>      }
> 
> -    if (state_dir == NULL) {
> -        state_dir = g_strdup(dfl_pathnames.state_dir);
> +    if (config->state_dir == NULL) {
> +        config->state_dir = g_strdup(dfl_pathnames.state_dir);
>      }
> 
>  #ifdef _WIN32
> @@ -1074,25 +1107,25 @@ int main(int argc, char **argv)
>       * error later on, we won't try to clean up the directory, it is considered
>       * persistent.
>       */
> -    if (g_mkdir_with_parents(state_dir, S_IRWXU) == -1) {
> +    if (g_mkdir_with_parents(config->state_dir, S_IRWXU) == -1) {
>          g_critical("unable to create (an ancestor of) the state directory"
> -                   " '%s': %s", state_dir, strerror(errno));
> +                   " '%s': %s", config->state_dir, strerror(errno));
>          return EXIT_FAILURE;
>      }
>  #endif
> 
>      s = g_malloc0(sizeof(GAState));
> -    s->log_level = log_level;
> +    s->log_level = config->log_level;
>      s->log_file = stderr;
>  #ifdef CONFIG_FSFREEZE
> -    s->fsfreeze_hook = fsfreeze_hook;
> +    s->fsfreeze_hook = config->fsfreeze_hook;
>  #endif
>      g_log_set_default_handler(ga_log, s);
>      g_log_set_fatal_mask(NULL, G_LOG_LEVEL_ERROR);
>      ga_enable_logging(s);
>      s->state_filepath_isfrozen = g_strdup_printf("%s/qga.state.isfrozen",
> -                                                 state_dir);
> -    s->pstate_filepath = g_strdup_printf("%s/qga.state", state_dir);
> +                                                 config->state_dir);
> +    s->pstate_filepath = g_strdup_printf("%s/qga.state", config->state_dir);
>      s->frozen = false;
> 
>  #ifndef _WIN32
> @@ -1125,23 +1158,23 @@ int main(int argc, char **argv)
>  #endif
> 
>      if (ga_is_frozen(s)) {
> -        if (daemonize) {
> +        if (config->daemonize) {
>              /* delay opening/locking of pidfile till filesystems are unfrozen */
> -            s->deferred_options.pid_filepath = pid_filepath;
> +            s->deferred_options.pid_filepath = config->pid_filepath;
>              become_daemon(NULL);
>          }
> -        if (log_filepath) {
> +        if (config->log_filepath) {
>              /* delay opening the log file till filesystems are unfrozen */
> -            s->deferred_options.log_filepath = log_filepath;
> +            s->deferred_options.log_filepath = config->log_filepath;
>          }
>          ga_disable_logging(s);
>          qmp_for_each_command(ga_disable_non_whitelisted, NULL);
>      } else {
> -        if (daemonize) {
> -            become_daemon(pid_filepath);
> +        if (config->daemonize) {
> +            become_daemon(config->pid_filepath);
>          }
> -        if (log_filepath) {
> -            FILE *log_file = ga_open_logfile(log_filepath);
> +        if (config->log_filepath) {
> +            FILE *log_file = ga_open_logfile(config->log_filepath);
>              if (!log_file) {
>                  g_critical("unable to open specified log file: %s",
>                             strerror(errno));
> @@ -1159,14 +1192,15 @@ int main(int argc, char **argv)
>          goto out_bad;
>      }
> 
> -    blacklist = ga_command_blacklist_init(blacklist);
> -    if (blacklist) {
> -        s->blacklist = blacklist;
> +    config->blacklist = ga_command_blacklist_init(config->blacklist);
> +    if (config->blacklist) {
> +        GList *l = config->blacklist;
> +        s->blacklist = config->blacklist;
>          do {
> -            g_debug("disabling command: %s", (char *)blacklist->data);
> -            qmp_disable_command(blacklist->data);
> -            blacklist = g_list_next(blacklist);
> -        } while (blacklist);
> +            g_debug("disabling command: %s", (char *)l->data);
> +            qmp_disable_command(l->data);
> +            l = g_list_next(l);
> +        } while (l);
>      }
>      s->command_state = ga_command_state_new();
>      ga_command_state_init(s, s->command_state);
> @@ -1181,14 +1215,14 @@ int main(int argc, char **argv)
>  #endif
> 
>      s->main_loop = g_main_loop_new(NULL, false);
> -    if (!channel_init(ga_state, method, channel_path)) {
> +    if (!channel_init(ga_state, config->method, config->channel_path)) {
>          g_critical("failed to initialize guest agent channel");
>          goto out_bad;
>      }
>  #ifndef _WIN32
>      g_main_loop_run(ga_state->main_loop);
>  #else
> -    if (daemonize) {
> +    if (config->daemonize) {
>          SERVICE_TABLE_ENTRY service_table[] = {
>              { (char *)QGA_SERVICE_NAME, service_main }, { NULL, NULL } };
>          StartServiceCtrlDispatcher(service_table);
> @@ -1200,24 +1234,17 @@ int main(int argc, char **argv)
>      ga_command_state_cleanup_all(ga_state->command_state);
>      ga_channel_free(ga_state->channel);
> 
> -    if (daemonize) {
> -        unlink(pid_filepath);
> +    if (config->daemonize) {
> +        unlink(config->pid_filepath);
>      }
>      return 0;
> 
>  out_bad:
> -    if (daemonize) {
> -        unlink(pid_filepath);
> +    if (config->daemonize) {
> +        unlink(config->pid_filepath);
>      }
> 
> -    g_free(method);
> -    g_free(log_filepath);
> -    g_free(pid_filepath);
> -    g_free(state_dir);
> -    g_free(channel_path);
> -#ifdef CONFIG_FSFREEZE
> -    g_free(fsfreeze_hook);
> -#endif
> +    config_free(config);
> 
>      return EXIT_FAILURE;
>  }
> -- 
> 2.4.3
>