]> git.tuebingen.mpg.de Git - paraslash.git/commitdiff
Merge branch 'maint'
authorAndre Noll <maan@tuebingen.mpg.de>
Sun, 6 May 2018 08:37:42 +0000 (10:37 +0200)
committerAndre Noll <maan@tuebingen.mpg.de>
Sun, 6 May 2018 08:37:42 +0000 (10:37 +0200)
This fix for an ancient bug should also be in master.

* maint:
  server: Fix return value of com_ff().

1  2 
command.c

diff --combined command.c
index 6568b789339b25125fd54fad90d03abeceb515a2,6777ccc971e2590bd2d46879ba428ff1f327f7d8..aac344bc8027bd1dd638450af629740fbc36d875
+++ b/command.c
@@@ -1,4 -1,8 +1,4 @@@
 -/*
 - * Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>
 - *
 - * Licensed under the GPL v2. For licencing details see COPYING.
 - */
 +/* Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
  
  /** \file command.c Client authentication and server commands. */
  
  #include <arpa/inet.h>
  #include <sys/un.h>
  #include <netdb.h>
 +#include <lopsub.h>
  
 +#include "server.lsg.h"
  #include "para.h"
  #include "error.h"
  #include "crypt.h"
  #include "sideband.h"
  #include "command.h"
 -#include "server.cmdline.h"
  #include "string.h"
  #include "afh.h"
  #include "afs.h"
 +#include "net.h"
  #include "server.h"
  #include "list.h"
  #include "send.h"
  #include "sched.h"
  #include "vss.h"
 -#include "net.h"
  #include "daemon.h"
  #include "fd.h"
  #include "ipc.h"
 +#include "server_cmd.lsg.h"
  #include "user_list.h"
 -#include "server.command_list.h"
 -#include "afs.command_list.h"
  #include "signal.h"
  #include "version.h"
  
 -typedef int server_command_handler_t(struct command_context *);
 -static server_command_handler_t SERVER_COMMAND_HANDLERS;
 -server_command_handler_t AFS_COMMAND_HANDLERS;
 -
 -/* Defines one command of para_server. */
 -struct server_command {
 -      /* The name of the command. */
 -      const char *name;
 -      /* Pointer to the function that handles the command. */
 -      server_command_handler_t *handler;
 -      /* The privileges a user must have to execute this command. */
 -      unsigned int perms;
 -      /* One-line description of the command. */
 -      const char *description;
 -      /* Summary of the command line options. */
 -      const char *usage;
 -      /* The long help text. */
 -      const char *help;
 -};
 -
 -static struct server_command afs_cmds[] = {DEFINE_AFS_CMD_ARRAY};
 -static struct server_command server_cmds[] = {DEFINE_SERVER_CMD_ARRAY};
 +#define SERVER_CMD_AUX_INFO(_arg) _arg,
 +static const unsigned server_command_perms[] = {LSG_SERVER_CMD_AUX_INFOS};
 +#undef SERVER_CMD_AUX_INFO
 +#define SERVER_CMD_AUX_INFO(_arg) #_arg,
 +static const char * const server_command_perms_txt[] = {LSG_SERVER_CMD_AUX_INFOS};
 +#undef SERVER_CMD_AUX_INFO
  
  /** Commands including options must be shorter than this. */
  #define MAX_COMMAND_LEN 32768
@@@ -73,6 -93,21 +73,6 @@@ static char *vss_status_tohuman(unsigne
        return para_strdup("paused");
  }
  
 -/*
 - * return human readable permission string. Never returns NULL.
 - */
 -static char *cmd_perms_itohuman(unsigned int perms)
 -{
 -      char *msg = para_malloc(5 * sizeof(char));
 -
 -      msg[0] = perms & AFS_READ? 'a' : '-';
 -      msg[1] = perms & AFS_WRITE? 'A' : '-';
 -      msg[2] = perms & VSS_READ? 'v' : '-';
 -      msg[3] = perms & VSS_WRITE? 'V' : '-';
 -      msg[4] = '\0';
 -      return msg;
 -}
 -
  /*
   * Never returns NULL.
   */
@@@ -88,7 -123,7 +88,7 @@@ static char *vss_get_status_flags(unsig
        return msg;
  }
  
 -static unsigned get_status(struct misc_meta_data *nmmd, int parser_friendly,
 +static unsigned get_status(struct misc_meta_data *nmmd, bool parser_friendly,
                char **result)
  {
        char *status, *flags; /* vss status info */
        clock_get_realtime(&current_time);
        /*
         * The calls to WRITE_STATUS_ITEM() below never fail because
 -       * b->max_size is zero (unlimited), see para_printf(). However, clang
 -       * is not smart enough to prove this and complains nevertheless.
 +       * b->max_size is zero (unlimited), see \ref para_printf(). However,
 +       * clang is not smart enough to prove this and complains nevertheless.
         * Casting the return value to void silences clang.
         */
 -      (void)WRITE_STATUS_ITEM(&b, SI_STATUS, "%s\n", status);
 -      (void)WRITE_STATUS_ITEM(&b, SI_STATUS_FLAGS, "%s\n", flags);
 -      (void)WRITE_STATUS_ITEM(&b, SI_OFFSET, "%li\n", offset);
 -      (void)WRITE_STATUS_ITEM(&b, SI_AFS_MODE, "%s\n", mmd->afs_mode_string);
 -      (void)WRITE_STATUS_ITEM(&b, SI_STREAM_START, "%lu.%lu\n",
 +      (void)WRITE_STATUS_ITEM(&b, SI_status, "%s\n", status);
 +      (void)WRITE_STATUS_ITEM(&b, SI_status_flags, "%s\n", flags);
 +      (void)WRITE_STATUS_ITEM(&b, SI_offset, "%li\n", offset);
 +      (void)WRITE_STATUS_ITEM(&b, SI_afs_mode, "%s\n", mmd->afs_mode_string);
 +      (void)WRITE_STATUS_ITEM(&b, SI_stream_start, "%lu.%lu\n",
                (long unsigned)nmmd->stream_start.tv_sec,
                (long unsigned)nmmd->stream_start.tv_usec);
 -      (void)WRITE_STATUS_ITEM(&b, SI_CURRENT_TIME, "%lu.%lu\n",
 +      (void)WRITE_STATUS_ITEM(&b, SI_current_time, "%lu.%lu\n",
                (long unsigned)current_time.tv_sec,
                (long unsigned)current_time.tv_usec);
        free(flags);
        return b.offset;
  }
  
 -static int check_sender_args(int argc, char * const * argv, struct sender_command_data *scd)
 -{
 -      int i;
 -
 -      const char *subcmds[] = {SENDER_SUBCOMMANDS NULL};
 -      scd->sender_num = -1;
 -      if (argc < 3)
 -              return -E_COMMAND_SYNTAX;
 -      for (i = 0; senders[i].name; i++)
 -              if (!strcmp(senders[i].name, argv[1]))
 -                      break;
 -      PARA_DEBUG_LOG("%d:%s\n", argc, argv[1]);
 -      if (!senders[i].name)
 -              return -E_COMMAND_SYNTAX;
 -      scd->sender_num = i;
 -      for (i = 0; subcmds[i]; i++)
 -              if (!strcmp(subcmds[i], argv[2]))
 -                      break;
 -      if (!subcmds[i])
 -              return -E_COMMAND_SYNTAX;
 -      scd->cmd_num = i;
 -      if (!senders[scd->sender_num].client_cmds[scd->cmd_num])
 -              return -E_SENDER_CMD;
 -      switch (scd->cmd_num) {
 -      case SENDER_on:
 -      case SENDER_off:
 -              if (argc != 3)
 -                      return -E_COMMAND_SYNTAX;
 -              break;
 -      case SENDER_deny:
 -      case SENDER_allow:
 -              if (argc != 4 || parse_cidr(argv[3], scd->host,
 -                              sizeof(scd->host), &scd->netmask) == NULL)
 -                      return -E_COMMAND_SYNTAX;
 -              break;
 -      case SENDER_add:
 -      case SENDER_delete:
 -              if (argc != 4)
 -                      return -E_COMMAND_SYNTAX;
 -              return parse_fec_url(argv[3], scd);
 -      default:
 -              return -E_COMMAND_SYNTAX;
 -      }
 -      return 1;
 -}
 -
  /**
   * Send a sideband packet through a blocking file descriptor.
   *
@@@ -198,81 -279,6 +198,81 @@@ int send_strerror(struct command_contex
        return send_sb_va(&cc->scc, SBD_ERROR_LOG, "%s\n", para_strerror(err));
  }
  
 +/**
 + * Send an error context to a client,
 + *
 + * \param cc Client info.
 + * \param errctx The error context string.
 + *
 + * \return The return value of the underlying call to send_sb_va().
 + *
 + * This function frees the error context string after it was sent.
 + */
 +int send_errctx(struct command_context *cc, char *errctx)
 +{
 +      int ret;
 +
 +      if (!errctx)
 +              return 0;
 +      ret = send_sb_va(&cc->scc, SBD_ERROR_LOG, "%s\n", errctx);
 +      free(errctx);
 +      return ret;
 +}
 +
 +static int check_sender_args(struct command_context *cc,
 +              struct lls_parse_result *lpr, struct sender_command_data *scd)
 +{
 +      int i, ret;
 +      const char * const subcmds[] = {SENDER_SUBCOMMANDS};
 +      const char *arg;
 +      char *errctx;
 +      unsigned num_inputs = lls_num_inputs(lpr);
 +
 +      scd->sender_num = -1;
 +      ret = lls(lls_check_arg_count(lpr, 2, INT_MAX, &errctx));
 +      if (ret < 0) {
 +              send_errctx(cc, errctx);
 +              return ret;
 +      }
 +      arg = lls_input(0, lpr);
 +      for (i = 0; senders[i].name; i++)
 +              if (!strcmp(senders[i].name, arg))
 +                      break;
 +      if (!senders[i].name)
 +              return -E_COMMAND_SYNTAX;
 +      scd->sender_num = i;
 +      arg = lls_input(1, lpr);
 +      for (i = 0; i < NUM_SENDER_CMDS; i++)
 +              if (!strcmp(subcmds[i], arg))
 +                      break;
 +      if (i == NUM_SENDER_CMDS)
 +              return -E_COMMAND_SYNTAX;
 +      scd->cmd_num = i;
 +      if (!senders[scd->sender_num].client_cmds[scd->cmd_num])
 +              return -E_SENDER_CMD;
 +      switch (scd->cmd_num) {
 +      case SENDER_on:
 +      case SENDER_off:
 +              if (num_inputs != 2)
 +                      return -E_COMMAND_SYNTAX;
 +              break;
 +      case SENDER_deny:
 +      case SENDER_allow:
 +              if (num_inputs != 3 || parse_cidr(lls_input(2, lpr), scd->host,
 +                              sizeof(scd->host), &scd->netmask) == NULL)
 +                      return -E_COMMAND_SYNTAX;
 +              break;
 +      case SENDER_add:
 +      case SENDER_delete:
 +              if (num_inputs != 3)
 +                      return -E_COMMAND_SYNTAX;
 +              return parse_fec_url(lls_input(2, lpr), scd);
 +      default:
 +              return -E_COMMAND_SYNTAX;
 +      }
 +      return 1;
 +}
 +
  /**
   * Send a sideband packet through a blocking file descriptor.
   *
@@@ -323,13 -329,13 +323,13 @@@ fail
        return ret;
  }
  
 -static int com_sender(struct command_context *cc)
 +static int com_sender(struct command_context *cc, struct lls_parse_result *lpr)
  {
        int i, ret = 0;
        char *msg = NULL;
        struct sender_command_data scd;
  
 -      if (cc->argc < 2) {
 +      if (lls_num_inputs(lpr) == 0) {
                for (i = 0; senders[i].name; i++) {
                        char *tmp;
                        ret = xasprintf(&tmp, "%s%s\n", msg? msg : "",
                }
                return send_sb(&cc->scc, msg, ret, SBD_OUTPUT, false);
        }
 -      ret = check_sender_args(cc->argc, cc->argv, &scd);
 +      ret = check_sender_args(cc, lpr, &scd);
        if (ret < 0) {
                if (scd.sender_num < 0)
                        return ret;
 -              if (strcmp(cc->argv[2], "status") == 0)
 +              if (strcmp(lls_input(1, lpr), "status") == 0)
                        msg = senders[scd.sender_num].status();
                else
                        msg = senders[scd.sender_num].help();
        case SENDER_add:
        case SENDER_delete:
                assert(senders[scd.sender_num].resolve_target);
 -              ret = senders[scd.sender_num].resolve_target(cc->argv[3], &scd);
 +              ret = senders[scd.sender_num].resolve_target(lls_input(2, lpr),
 +                      &scd);
                if (ret < 0)
                        return ret;
        }
        }
        return (i < 10)? 1 : -E_LOCK;
  }
 +EXPORT_SERVER_CMD_HANDLER(sender);
  
 -/* server info */
 -static int com_si(struct command_context *cc)
 +static int com_si(struct command_context *cc,
 +              __a_unused struct lls_parse_result *lpr)
  {
 -      int ret;
        char *msg, *ut;
 +      int ret;
  
 -      if (cc->argc != 1)
 -              return -E_COMMAND_SYNTAX;
 -      mutex_lock(mmd_mutex);
        ut = daemon_get_uptime_str(now);
 +      mutex_lock(mmd_mutex);
        ret = xasprintf(&msg,
                "up: %s\nplayed: %u\n"
                "server_pid: %d\n"
                "supported audio formats: %s\n",
                ut, mmd->num_played,
                (int)getppid(),
 -              (int)mmd->afs_pid,
 +              (int)afs_pid,
                mmd->active_connections,
                mmd->num_commands,
                mmd->num_connects,
 -              conf.loglevel_arg,
 +              ENUM_STRING_VAL(LOGLEVEL),
                AUDIO_FORMAT_HANDLERS
        );
        mutex_unlock(mmd_mutex);
        free(ut);
        return send_sb(&cc->scc, msg, ret, SBD_OUTPUT, false);
  }
 +EXPORT_SERVER_CMD_HANDLER(si);
  
 -/* version */
 -static int com_version(struct command_context *cc)
 +static int com_version(struct command_context *cc, struct lls_parse_result *lpr)
  {
        char *msg;
        size_t len;
  
 -      if (cc->argc > 1 && strcmp(cc->argv[1], "-v") == 0)
 +      if (SERVER_CMD_OPT_GIVEN(VERSION, VERBOSE, lpr))
                len = xasprintf(&msg, "%s", version_text("server"));
        else
                len = xasprintf(&msg, "%s\n", version_single_line("server"));
        return send_sb(&cc->scc, msg, len, SBD_OUTPUT, false);
  }
 +EXPORT_SERVER_CMD_HANDLER(version);
  
  /** These status items are cleared if no audio file is currently open. */
  #define EMPTY_STATUS_ITEMS \
 -      ITEM(PATH) \
 -      ITEM(DIRECTORY) \
 -      ITEM(BASENAME) \
 -      ITEM(SCORE) \
 -      ITEM(ATTRIBUTES_BITMAP) \
 -      ITEM(ATTRIBUTES_TXT) \
 -      ITEM(HASH) \
 -      ITEM(IMAGE_ID) \
 -      ITEM(IMAGE_NAME) \
 -      ITEM(LYRICS_ID) \
 -      ITEM(LYRICS_NAME) \
 -      ITEM(BITRATE) \
 -      ITEM(FORMAT) \
 -      ITEM(FREQUENCY) \
 -      ITEM(CHANNELS) \
 -      ITEM(DURATION) \
 -      ITEM(SECONDS_TOTAL) \
 -      ITEM(NUM_PLAYED) \
 -      ITEM(LAST_PLAYED) \
 -      ITEM(TECHINFO) \
 -      ITEM(ARTIST) \
 -      ITEM(TITLE) \
 -      ITEM(YEAR) \
 -      ITEM(ALBUM) \
 -      ITEM(COMMENT) \
 -      ITEM(MTIME) \
 -      ITEM(FILE_SIZE) \
 -      ITEM(CHUNK_TIME) \
 -      ITEM(NUM_CHUNKS) \
 -      ITEM(AMPLIFICATION) \
 +      ITEM(path) \
 +      ITEM(directory) \
 +      ITEM(basename) \
 +      ITEM(score) \
 +      ITEM(attributes_bitmap) \
 +      ITEM(attributes_txt) \
 +      ITEM(hash) \
 +      ITEM(image_id) \
 +      ITEM(image_name) \
 +      ITEM(lyrics_id) \
 +      ITEM(lyrics_name) \
 +      ITEM(bitrate) \
 +      ITEM(format) \
 +      ITEM(frequency) \
 +      ITEM(channels) \
 +      ITEM(duration) \
 +      ITEM(seconds_total) \
 +      ITEM(num_played) \
 +      ITEM(last_played) \
 +      ITEM(techinfo) \
 +      ITEM(artist) \
 +      ITEM(title) \
 +      ITEM(year) \
 +      ITEM(album) \
 +      ITEM(comment) \
 +      ITEM(mtime) \
 +      ITEM(file_size) \
 +      ITEM(chunk_time) \
 +      ITEM(num_chunks) \
 +      ITEM(amplification) \
  
 -/**
 - * Write a list of audio-file related status items with empty values.
 - *
 - * This is used by vss when currently no audio file is open.
 +/*
 + * Create a set of audio-file related status items with empty values. These are
 + * written to stat clients when no audio file is open.
   */
 -static unsigned empty_status_items(int parser_friendly, char **result)
 +static unsigned empty_status_items(bool parser_friendly, char **result)
  {
        char *esi;
        unsigned len;
  }
  #undef EMPTY_STATUS_ITEMS
  
 -/* stat */
 -static int com_stat(struct command_context *cc)
 +static int com_stat(struct command_context *cc, struct lls_parse_result *lpr)
  {
 -      int i, ret;
 +      int ret;
        struct misc_meta_data tmp, *nmmd = &tmp;
        char *s;
 -      int32_t num = 0;
 -      int parser_friendly = 0;
 +      bool parser_friendly = SERVER_CMD_OPT_GIVEN(STAT, PARSER_FRIENDLY,
 +              lpr) > 0;
 +      uint32_t num = SERVER_CMD_UINT32_VAL(STAT, NUM, lpr);
  
        para_sigaction(SIGUSR1, dummy);
 -
 -      for (i = 1; i < cc->argc; i++) {
 -              const char *arg = cc->argv[i];
 -              if (arg[0] != '-')
 -                      break;
 -              if (!strcmp(arg, "--")) {
 -                      i++;
 -                      break;
 -              }
 -              if (!strncmp(arg, "-n=", 3)) {
 -                      ret = para_atoi32(arg + 3, &num);
 -                      if (ret < 0)
 -                              return ret;
 -                      continue;
 -              }
 -              if (!strcmp(arg, "-p")) {
 -                      parser_friendly = 1;
 -                      continue;
 -              }
 -              return -E_COMMAND_SYNTAX;
 -      }
 -      if (i != cc->argc)
 -              return -E_COMMAND_SYNTAX;
        for (;;) {
                /*
                 * Copy the mmd structure to minimize the time we hold the mmd
  out:
        return ret;
  }
 +EXPORT_SERVER_CMD_HANDLER(stat);
  
 -static int send_list_of_commands(struct command_context *cc, struct server_command *cmd,
 -              const char *handler)
 +/* fixed-length, human readable permission string */
 +const char *server_cmd_perms_str(unsigned int perms)
  {
 -      char *msg = NULL;
 +      static char result[5];
  
 -      for (; cmd->name; cmd++) {
 -              char *tmp, *perms = cmd_perms_itohuman(cmd->perms);
 -              tmp = make_message("%s\t%s\t%s\t%s\n", cmd->name, handler,
 -                      perms, cmd->description);
 -              free(perms);
 -              msg = para_strcat(msg, tmp);
 -              free(tmp);
 -      }
 -      assert(msg);
 -      return send_sb(&cc->scc, msg, strlen(msg), SBD_OUTPUT, false);
 +      result[0] = perms & AFS_READ? 'a' : '-';
 +      result[1] = perms & AFS_WRITE? 'A' : '-';
 +      result[2] = perms & VSS_READ? 'v' : '-';
 +      result[3] = perms & VSS_WRITE? 'V' : '-';
 +      result[4] = '\0';
 +      return result;
  }
  
 -/* returns string that must be freed by the caller */
 -static struct server_command *get_cmd_ptr(const char *name, char **handler)
 +static int send_list_of_commands(struct command_context *cc)
  {
 -      struct server_command *cmd;
 -
 -      for (cmd = server_cmds; cmd->name; cmd++)
 -              if (!strcmp(cmd->name, name)) {
 -                      if (handler)
 -                              *handler = para_strdup("server"); /* server commands */
 -                      return cmd;
 -              }
 -      /* not found, look for commands supported by afs */
 -      for (cmd = afs_cmds; cmd->name; cmd++)
 -              if (!strcmp(cmd->name, name)) {
 -                      if (handler)
 -                              *handler = para_strdup("afs");
 -                      return cmd;
 -              }
 -      return NULL;
 +      int i;
 +      const struct lls_command *cmd;
 +      char *msg = para_strdup("");
 +
 +      for (i = 1; (cmd = lls_cmd(i, server_cmd_suite)); i++) {
 +              const char *perms = server_cmd_perms_str(server_command_perms[i]);
 +              char *tmp = make_message("%s%s\t%s\t%s\n", msg,
 +                      lls_command_name(cmd), perms, lls_purpose(cmd));
 +              free(msg);
 +              msg = tmp;
 +      }
 +      return send_sb(&cc->scc, msg, strlen(msg), SBD_OUTPUT, false);
  }
  
 -/* help */
 -static int com_help(struct command_context *cc)
 +static int com_help(struct command_context *cc, struct lls_parse_result *lpr)
  {
 -      struct server_command *cmd;
 -      char *perms, *handler, *buf;
 +      const char *perms;
 +      char *long_help, *buf, *errctx;
        int ret;
 +      const struct lls_command *cmd;
  
 -      if (cc->argc < 2) {
 -              /* no argument given, print list of commands */
 -              if ((ret = send_list_of_commands(cc, server_cmds, "server")) < 0)
 -                      return ret;
 -              return send_list_of_commands(cc, afs_cmds, "afs");
 +      ret = lls(lls_check_arg_count(lpr, 0, 1, &errctx));
 +      if (ret < 0) {
 +              send_errctx(cc, errctx);
 +              return ret;
        }
 +      if (lls_num_inputs(lpr) == 0)
 +              return send_list_of_commands(cc);
        /* argument given for help */
 -      cmd = get_cmd_ptr(cc->argv[1], &handler);
 -      if (!cmd)
 -              return -E_BAD_CMD;
 -      perms = cmd_perms_itohuman(cmd->perms);
 -      ret = xasprintf(&buf, "%s - %s\n\n"
 -              "handler: %s\n"
 -              "permissions: %s\n"
 -              "usage: %s\n\n"
 -              "%s\n",
 -              cc->argv[1],
 -              cmd->description,
 -              handler,
 -              perms,
 -              cmd->usage,
 -              cmd->help
 -      );
 -      free(perms);
 -      free(handler);
 +      ret = lls(lls_lookup_subcmd(lls_input(0, lpr), server_cmd_suite,
 +              &errctx));
 +      if (ret < 0) {
 +              send_errctx(cc, errctx);
 +              return ret;
 +      }
 +      cmd = lls_cmd(ret, server_cmd_suite);
 +      perms = server_command_perms_txt[ret];
 +      long_help = lls_long_help(cmd);
 +      assert(long_help);
 +      ret = xasprintf(&buf, "%spermissions: %s\n", long_help, perms);
 +      free(long_help);
        return send_sb(&cc->scc, buf, ret, SBD_OUTPUT, false);
  }
 +EXPORT_SERVER_CMD_HANDLER(help);
  
 -/* hup */
 -static int com_hup(struct command_context *cc)
 +static int com_hup(__a_unused struct command_context *cc,
 +              __a_unused struct lls_parse_result *lpr)
  {
 -      if (cc->argc != 1)
 -              return -E_COMMAND_SYNTAX;
        kill(getppid(), SIGHUP);
        return 1;
  }
 +EXPORT_SERVER_CMD_HANDLER(hup);
  
 -/* term */
 -static int com_term(struct command_context *cc)
 +static int com_term(__a_unused struct command_context *cc,
 +              __a_unused struct lls_parse_result *lpr)
  {
 -      if (cc->argc != 1)
 -              return -E_COMMAND_SYNTAX;
        kill(getppid(), SIGTERM);
        return 1;
  }
 +EXPORT_SERVER_CMD_HANDLER(term);
  
 -static int com_play(struct command_context *cc)
 +static int com_play(__a_unused struct command_context *cc,
 +              __a_unused struct lls_parse_result *lpr)
  {
 -      if (cc->argc != 1)
 -              return -E_COMMAND_SYNTAX;
        mutex_lock(mmd_mutex);
        mmd->new_vss_status_flags |= VSS_PLAYING;
        mmd->new_vss_status_flags &= ~VSS_NOMORE;
        mutex_unlock(mmd_mutex);
        return 1;
  }
 +EXPORT_SERVER_CMD_HANDLER(play);
  
 -/* stop */
 -static int com_stop(struct command_context *cc)
 +static int com_stop(__a_unused struct command_context *cc,
 +              __a_unused struct lls_parse_result *lpr)
  {
 -      if (cc->argc != 1)
 -              return -E_COMMAND_SYNTAX;
        mutex_lock(mmd_mutex);
        mmd->new_vss_status_flags &= ~VSS_PLAYING;
        mmd->new_vss_status_flags &= ~VSS_REPOS;
        mutex_unlock(mmd_mutex);
        return 1;
  }
 +EXPORT_SERVER_CMD_HANDLER(stop);
  
 -/* pause */
 -static int com_pause(struct command_context *cc)
 +static int com_pause(__a_unused struct command_context *cc,
 +              __a_unused struct lls_parse_result *lpr)
  {
 -      if (cc->argc != 1)
 -              return -E_COMMAND_SYNTAX;
        mutex_lock(mmd_mutex);
        if (!vss_paused() && !vss_stopped()) {
                mmd->events++;
        mutex_unlock(mmd_mutex);
        return 1;
  }
 +EXPORT_SERVER_CMD_HANDLER(pause);
  
 -/* next */
 -static int com_next(struct command_context *cc)
 +static int com_next(__a_unused struct command_context *cc,
 +              __a_unused struct lls_parse_result *lpr)
  {
 -      if (cc->argc != 1)
 -              return -E_COMMAND_SYNTAX;
        mutex_lock(mmd_mutex);
        mmd->events++;
        mmd->new_vss_status_flags |= VSS_NEXT;
        mutex_unlock(mmd_mutex);
        return 1;
  }
 +EXPORT_SERVER_CMD_HANDLER(next);
  
 -/* nomore */
 -static int com_nomore(struct command_context *cc)
 +static int com_nomore(__a_unused struct command_context *cc,
 +              __a_unused struct lls_parse_result *lpr)
  {
 -      if (cc->argc != 1)
 -              return -E_COMMAND_SYNTAX;
        mutex_lock(mmd_mutex);
        if (vss_playing() || vss_paused())
                mmd->new_vss_status_flags |= VSS_NOMORE;
        mutex_unlock(mmd_mutex);
        return 1;
  }
 +EXPORT_SERVER_CMD_HANDLER(nomore);
  
 -/* ff */
 -static int com_ff(struct command_context *cc)
 +static int com_ff(__a_unused struct command_context *cc,
 +              struct lls_parse_result *lpr)
  {
        long promille;
        int ret, backwards = 0;
        unsigned i;
 -      char c;
 +      char c, *errctx;
  
 -      if (cc->argc != 2)
 -              return -E_COMMAND_SYNTAX;
 -      if (!(ret = sscanf(cc->argv[1], "%u%c", &i, &c)))
 +      ret = lls(lls_check_arg_count(lpr, 1, 1, &errctx));
 +      if (ret < 0) {
 +              send_errctx(cc, errctx);
 +              return ret;
 +      }
 +      if (!(ret = sscanf(lls_input(0, lpr), "%u%c", &i, &c)))
                return -E_COMMAND_SYNTAX;
        if (ret > 1 && c == '-')
                backwards = 1; /* jmp backwards */
        ret = -E_NO_AUDIO_FILE;
        if (!mmd->afd.afhi.chunks_total || !mmd->afd.afhi.seconds_total)
                goto out;
+       ret = 1;
        promille = (1000 * mmd->current_chunk) / mmd->afd.afhi.chunks_total;
        if (backwards)
                promille -= 1000 * i / mmd->afd.afhi.seconds_total;
        mmd->new_vss_status_flags |= VSS_REPOS;
        mmd->new_vss_status_flags &= ~VSS_NEXT;
        mmd->events++;
-       ret = 1;
  out:
        mutex_unlock(mmd_mutex);
        return ret;
  }
 +EXPORT_SERVER_CMD_HANDLER(ff);
  
 -/* jmp */
 -static int com_jmp(struct command_context *cc)
 +static int com_jmp(__a_unused struct command_context *cc,
 +              struct lls_parse_result *lpr)
  {
        long unsigned int i;
        int ret;
 +      char *errctx;
  
 -      if (cc->argc != 2)
 -              return -E_COMMAND_SYNTAX;
 -      if (sscanf(cc->argv[1], "%lu", &i) <= 0)
 -              return -E_COMMAND_SYNTAX;
 +      ret = lls(lls_check_arg_count(lpr, 1, 1, &errctx));
 +      if (ret < 0) {
 +              send_errctx(cc, errctx);
 +              return ret;
 +      }
 +      if (sscanf(lls_input(0, lpr), "%lu", &i) <= 0)
 +              return -ERRNO_TO_PARA_ERROR(EINVAL);
        mutex_lock(mmd_mutex);
        ret = -E_NO_AUDIO_FILE;
        if (!mmd->afd.afhi.chunks_total)
@@@ -738,15 -777,26 +738,15 @@@ out
        mutex_unlock(mmd_mutex);
        return ret;
  }
 +EXPORT_SERVER_CMD_HANDLER(jmp);
  
 -static int com_tasks(struct command_context *cc)
 -{
 -      char *tl = server_get_tasks();
 -      int ret = 1;
 -
 -      if (tl)
 -              ret = send_sb(&cc->scc, tl, strlen(tl), SBD_OUTPUT, false);
 -      return ret;
 -}
 -
 -/*
 - * check if perms are sufficient to exec a command having perms cmd_perms.
 - * Returns 0 if perms are sufficient, -E_PERM otherwise.
 - */
 -static int check_perms(unsigned int perms, const struct server_command *cmd_ptr)
 +/* deprecated, does nothing */
 +static int com_tasks(__a_unused struct command_context *cc,
 +              __a_unused struct lls_parse_result *lpr)
  {
 -      PARA_DEBUG_LOG("checking permissions\n");
 -      return (cmd_ptr->perms & perms) < cmd_ptr->perms ? -E_PERM : 0;
 +      return 1;
  }
 +EXPORT_SERVER_CMD_HANDLER(tasks);
  
  static void reset_signals(void)
  {
  }
  
  struct connection_features {
 -      bool aes_ctr128_requested;
 +      int dummy; /* none at the moment */
  };
  
  static int parse_auth_request(char *buf, int len, struct user **u,
                        if (strcmp(features[i], "sideband") == 0)
                                continue;
                        if (strcmp(features[i], "aes_ctr128") == 0)
 -                              cf->aes_ctr128_requested = true;
 +                              continue;
                        else {
                                ret = -E_BAD_FEATURE;
                                goto out;
@@@ -803,52 -853,40 +803,52 @@@ out
  
  #define HANDSHAKE_BUFSIZE 4096
  
 -static int run_command(struct command_context *cc, struct iovec *iov,
 -              const char *peername)
 +static int run_command(struct command_context *cc, struct iovec *iov)
  {
 -      int ret, i;
 -      char *p, *end;
 -      struct server_command *cmd;
 +      int ret, i, argc;
 +      char *p, *end, **argv;
 +      const struct lls_command *lcmd = NULL;
 +      unsigned perms;
 +      struct lls_parse_result *lpr;
 +      char *errctx;
  
        if (iov->iov_base == NULL || iov->iov_len == 0)
 -              return -E_BAD_CMD;
 +              return -ERRNO_TO_PARA_ERROR(EINVAL);
        p = iov->iov_base;
        p[iov->iov_len - 1] = '\0'; /* just to be sure */
 -      cmd = get_cmd_ptr(p, NULL);
 -      if (!cmd)
 -              return -E_BAD_CMD;
 -      ret = check_perms(cc->u->perms, cmd);
 -      if (ret < 0)
 +
 +      ret = lls(lls_lookup_subcmd(p, server_cmd_suite, &errctx));
 +      if (ret < 0) {
 +              send_errctx(cc, errctx);
                return ret;
 +      }
 +      perms = server_command_perms[ret];
 +      if ((perms & cc->u->perms) != perms)
 +              return -E_PERM;
 +      lcmd = lls_cmd(ret, server_cmd_suite);
        end = iov->iov_base + iov->iov_len;
        for (i = 0; p < end; i++)
                p += strlen(p) + 1;
 -      cc->argc = i;
 -      cc->argv = para_malloc((cc->argc + 1) * sizeof(char *));
 +      argc = i;
 +      argv = para_malloc((argc + 1) * sizeof(char *));
        for (i = 0, p = iov->iov_base; p < end; i++) {
 -              cc->argv[i] = para_strdup(p);
 +              argv[i] = para_strdup(p);
                p += strlen(p) + 1;
        }
 -      cc->argv[cc->argc] = NULL;
 -      PARA_NOTICE_LOG("calling com_%s() for %s@%s\n", cmd->name,
 -              cc->u->name, peername);
 -      ret = cmd->handler(cc);
 -      free_argv(cc->argv);
 +      argv[argc] = NULL;
 +      PARA_NOTICE_LOG("calling com_%s() for user %s\n",
 +              lls_command_name(lcmd), cc->u->name);
 +      ret = lls(lls_parse(argc, argv, lcmd, &lpr, &errctx));
 +      if (ret >= 0) {
 +              const struct server_cmd_user_data *ud = lls_user_data(lcmd);
 +              ret = ud->handler(cc, lpr);
 +              lls_free_parse_result(lpr, lcmd);
 +      } else
 +              send_errctx(cc, errctx);
 +      free_argv(argv);
        mutex_lock(mmd_mutex);
        mmd->num_commands++;
 -      if (ret >= 0 && (cmd->perms & AFS_WRITE))
 +      if (ret >= 0 && (perms & AFS_WRITE))
                mmd->events++;
        mutex_unlock(mmd_mutex);
        return ret;
   * Perform user authentication and execute a command.
   *
   * \param fd The file descriptor to send output to.
 - * \param peername Identifies the connecting peer.
   *
   * Whenever para_server accepts an incoming tcp connection on the port it
   * listens on, it forks and the resulting child calls this function.
   * permissions to execute that command, the function calls the corresponding
   * command handler which does argument checking and further processing.
   *
 - * In order to cope with DOS attacks, a timeout is set up which terminates
 + * In order to cope with DOS attacks, a timeout is set up which terminates
   * the function if the connection was not authenticated when the timeout
   * expires.
   *
 - * \sa alarm(2), crypt.c, crypt.h
 + * \sa alarm(2), \ref crypt.c, \ref crypt.h.
   */
 -__noreturn void handle_connect(int fd, const char *peername)
 +__noreturn void handle_connect(int fd)
  {
        int ret;
        unsigned char rand_buf[CHALLENGE_SIZE + 2 * SESSION_KEY_LEN];
        unsigned char challenge_hash[HASH_SIZE];
        char *command = NULL, *buf = para_malloc(HANDSHAKE_BUFSIZE) /* must be on the heap */;
        size_t numbytes;
 -      struct command_context cc_struct = {.peer = peername}, *cc = &cc_struct;
 +      struct command_context cc_struct = {.u = NULL}, *cc = &cc_struct;
        struct iovec iov;
        struct connection_features cf;
  
        alarm(0);
        PARA_INFO_LOG("good auth for %s\n", cc->u->name);
        /* init stream cipher keys with the second part of the random buffer */
 -      cc->scc.recv = sc_new(rand_buf + CHALLENGE_SIZE, SESSION_KEY_LEN,
 -              cf.aes_ctr128_requested);
 +      cc->scc.recv = sc_new(rand_buf + CHALLENGE_SIZE, SESSION_KEY_LEN);
        cc->scc.send = sc_new(rand_buf + CHALLENGE_SIZE + SESSION_KEY_LEN,
 -              SESSION_KEY_LEN, cf.aes_ctr128_requested);
 +              SESSION_KEY_LEN);
        ret = send_sb(&cc->scc, NULL, 0, SBD_PROCEED, false);
        if (ret < 0)
                goto net_err;
        ret = recv_sb(&cc->scc, SBD_COMMAND, MAX_COMMAND_LEN, &iov);
        if (ret < 0)
                goto net_err;
 -      ret = run_command(cc, &iov, peername);
 +      ret = run_command(cc, &iov);
        free(iov.iov_base);
        if (ret < 0)
                goto err_out;