]> git.tuebingen.mpg.de Git - dss.git/commitdiff
Merge topic branch t/realpath into pu
authorAndre Noll <maan@tuebingen.mpg.de>
Mon, 6 May 2024 20:31:16 +0000 (22:31 +0200)
committerAndre Noll <maan@tuebingen.mpg.de>
Mon, 6 May 2024 20:31:16 +0000 (22:31 +0200)
Started on 2024-04-27

* refs/heads/t/realpath:
  Resolve config file path only once.
  Use standard realpath().

1  2 
dss.c
ipc.c

diff --combined dss.c
index 7d906b2fa19552eb03087e9a4cfe64a39eceefa6,e709d34e0d7a0d6b12a3d74b3c0f0d7eaa901c2d..f7919c0dfd267f21bad649845642f5003e0a3c83
--- 1/dss.c
--- 2/dss.c
+++ b/dss.c
@@@ -65,6 -65,8 +65,8 @@@ static const struct lls_command *subcmd
  static bool daemonized;
  /** Non-NULL if we log to a file. */
  static FILE *logfile;
+ /* Realpath of the config file. */
+ static char *config_file;
  /** The read end of the signal pipe */
  static int signal_pipe;
  /** Process id of current pre-create-hook/rsync/post-create-hook process. */
@@@ -271,27 -273,37 +273,37 @@@ static __printf_1_2 void dss_msg(const 
        va_end(argp);
  }
  
- static char *get_config_file_name(void)
+ static void set_config_file_name(void)
  {
-       char *home, *config_file;
  
-       if (OPT_GIVEN(DSS, CONFIG_FILE))
-               return dss_strdup(OPT_STRING_VAL(DSS, CONFIG_FILE));
-       home = get_homedir();
-       config_file = make_message("%s/.dssrc", home);
-       free(home);
-       return config_file;
+       if (OPT_GIVEN(DSS, CONFIG_FILE)) {
+               const char *arg = OPT_STRING_VAL(DSS, CONFIG_FILE);
+               config_file = realpath(arg, NULL);
+               if (!config_file) {
+                       DSS_EMERG_LOG(("could not resolve path %s: %s\n", arg,
+                               strerror(errno)));
+                       exit(EXIT_FAILURE);
+               }
+       } else {
+               char *home = get_homedir();
+               char *arg = make_message("%s/.dssrc", home);
+               free(home);
+               config_file = realpath(arg, NULL);
+               if (config_file)
+                       free(arg);
+               else /* not fatal */
+                       config_file = arg;
+       }
+       DSS_DEBUG_LOG(("config file: %s\n", config_file));
  }
  
  static int send_signal(int sig, bool wait)
  {
        pid_t pid;
-       char *config_file = get_config_file_name();
        int ret = get_dss_pid(config_file, &pid);
        unsigned ms = 32;
        struct timespec ts;
  
-       free(config_file);
        if (ret < 0)
                return ret;
        if (OPT_GIVEN(DSS, DRY_RUN)) {
@@@ -1166,7 -1178,6 +1178,6 @@@ static int lopsub_error(int lopsub_ret
  static int parse_config_file(bool sighup, const struct lls_command *cmd)
  {
        int ret, fd = -1;
-       char *config_file = get_config_file_name();
        struct stat statbuf;
        void *map;
        size_t sz;
@@@ -1258,7 -1269,6 +1269,6 @@@ close_fd
        if (fd >= 0)
                close(fd);
  out:
-       free(config_file);
        return ret;
  }
  
@@@ -1589,10 -1599,8 +1599,8 @@@ static void exit_hook(int exit_code
  
  static void lock_dss_or_die(void)
  {
-       char *config_file = get_config_file_name();
        int ret = lock_dss(config_file);
  
-       free(config_file);
        if (ret < 0) {
                DSS_EMERG_LOG(("failed to lock: %s\n", dss_strerror(-ret)));
                exit(EXIT_FAILURE);
  static int com_run(void)
  {
        int ret, fd = -1;
-       char *config_file;
        pid_t pid;
  
        if (OPT_GIVEN(DSS, DRY_RUN)) {
                DSS_ERROR_LOG(("dry run not supported by this command\n"));
                return -E_SYNTAX;
        }
-       config_file = get_config_file_name();
        ret = get_dss_pid(config_file, &pid);
-       free(config_file);
        if (ret >= 0) {
                DSS_ERROR_LOG(("pid %d\n", (int)pid));
                return -E_ALREADY_RUNNING;
@@@ -1820,7 -1825,6 +1825,7 @@@ static int setup_signal_handling(void
        return install_sighandler(SIGCHLD);
  }
  
 +const char *dss_version(void);
  static void handle_version_and_help(void)
  {
        char *txt;
        else if (OPT_GIVEN(DSS, HELP))
                txt = lls_short_help(CMD_PTR(DSS));
        else if (OPT_GIVEN(DSS, VERSION))
 -              txt = make_message("%s\n", VERSION_STRING);
 +              txt = make_message("%s\n", dss_version());
        else
                return;
        printf("%s", txt);
        exit(EXIT_SUCCESS);
  }
  
 -static void show_subcommand_summary(void)
 +static void show_subcommand_summary(bool verbose)
  {
        const struct lls_command *cmd;
        int i;
  
 -      printf("Available subcommands:\n");
 +      printf("Available subcommands: ");
 +      if (!verbose) {
 +              for (i = 1; (cmd = lls_cmd(i, dss_suite)); i++) {
 +                      if (i > 1)
 +                              printf(", ");
 +                      printf("%s", lls_command_name(cmd));
 +              }
 +              printf("\n");
 +              return;
 +      }
 +      printf("\n");
        for (i = 1; (cmd = lls_cmd(i, dss_suite)); i++) {
                const char *name = lls_command_name(cmd);
                const char *purpose = lls_purpose(cmd);
                printf("%-11s%s\n", name, purpose);
        }
 -      exit(EXIT_SUCCESS);
  }
  
 +static int com_help(void)
 +{
 +      int ret;
 +      char *errctx, *help;
 +      const char *arg;
 +      const struct lls_command *cmd;
 +
 +      ret = lls_check_arg_count(sublpr, 0, 1, &errctx);
 +      if (ret < 0)
 +              return lopsub_error(ret, &errctx);
 +      if (lls_num_inputs(sublpr) == 0) {
 +              show_subcommand_summary(OPT_GIVEN(HELP, LONG));
 +              return 0;
 +      }
 +      arg = lls_input(0, sublpr);
 +      ret = lls_lookup_subcmd(arg, dss_suite, &errctx);
 +      if (ret < 0)
 +              return lopsub_error(ret, &errctx);
 +      cmd = lls_cmd(ret, dss_suite);
 +      if (OPT_GIVEN(HELP, LONG))
 +              help = lls_long_help(cmd);
 +      else
 +              help = lls_short_help(cmd);
 +      printf("%s\n", help);
 +      free(help);
 +      return 0;
 +}
 +EXPORT_CMD_HANDLER(help);
 +
  int main(int argc, char **argv)
  {
        int ret;
                goto out;
        }
        lpr = cmdline_lpr;
+       set_config_file_name();
        ret = parse_config_file(false /* no SIGHUP */, CMD_PTR(DSS));
        if (ret < 0)
                goto out;
        handle_version_and_help();
        num_inputs = lls_num_inputs(lpr);
 -      if (num_inputs == 0)
 -              show_subcommand_summary();
 +      if (num_inputs == 0) { /* show verbose summary */
 +              show_subcommand_summary(true);
 +              ret = 0;
 +              goto out;
 +      }
        ret = lls_lookup_subcmd(argv[argc - num_inputs], dss_suite, &errctx);
        if (ret < 0) {
                ret = lopsub_error(ret, &errctx);
@@@ -1951,5 -1915,6 +1957,6 @@@ out
        lls_free_parse_result(sublpr, subcmd);
        if (sublpr != cmdline_sublpr)
                lls_free_parse_result(cmdline_sublpr, subcmd);
+       free(config_file);
        exit(ret >= 0? EXIT_SUCCESS : EXIT_FAILURE);
  }
diff --combined ipc.c
index 7e870533a8fbbdff5a35703be7fd434b8205924c,2ccd156abb283a8cc0c7eeb33750edd6bc8da60b..d814d8f6e457759bd6f40a014435d12d1699cbf9
--- 1/ipc.c
--- 2/ipc.c
+++ b/ipc.c
@@@ -33,7 -33,7 +33,7 @@@
  
  /*
   * SuperFastHash, by Paul Hsieh.
 - * http://www.azillionmonkeys.com/qed/hash.html
 + * https://www.azillionmonkeys.com/qed/hash.html
   */
  static uint32_t super_fast_hash(const uint8_t *data, uint32_t len, uint32_t hash)
  {
        return hash;
  }
  
- /*
-  * Return the canonical absolute name of a given file name.
-  *
-  * Slightly modified version of glibc's realpath, Copyright (C)
-  * 1996-2002,2004,2005,2006,2008 Free Software Foundation, Inc.
-  *
-  * A canonical name does not contain any `.', `..' components nor any repeated
-  * path separators ('/') or symlinks. All path components must exist. The
-  * result is malloc'd and must be freed by the caller.
-  */
- static int dss_realpath(const char *name, char **resolved_path)
- {
-       char *rpath = NULL, *dest, *extra_buf = NULL;
-       const char *start, *end, *rpath_limit;
-       long int path_max;
-       int ret, num_links = 0;
-       if (name[0] == '\0') {
-               /*
-                * As per Single Unix Specification V2 we must return an error
-                * if the name argument points to an empty string.
-                */
-               ret = -ERRNO_TO_DSS_ERROR(ENOENT);
-               goto error;
-       }
- #ifdef PATH_MAX
-       path_max = PATH_MAX;
- #else
-       /*
-        * From realpath(3): Asking pathconf(3) does not really help, since on
-        * the one hand POSIX warns that the result of pathconf(3) may be
-        * huge and unsuitable for mallocing memory. And on the other hand
-        * pathconf(3) may return -1 to signify that PATH_MAX is not bounded.
-        */
-       path_max = pathconf(name, _PC_PATH_MAX);
-       if (path_max <= 0 || path_max >= 4096)
-               path_max = 4096;
- #endif
-       rpath = dss_malloc(path_max);
-       rpath_limit = rpath + path_max;
-       if (name[0] != '/') {
-               if (!getcwd(rpath, path_max)) {
-                       ret = -ERRNO_TO_DSS_ERROR(errno);
-                       goto error;
-               }
-               dest = memchr(rpath, '\0', path_max);
-       } else {
-               rpath[0] = '/';
-               dest = rpath + 1;
-       }
-       for (start = end = name; *start; start = end) {
-               struct stat st;
-               int n;
-               /* Skip sequence of multiple path-separators.  */
-               while (*start == '/')
-                       ++start;
-               /* Find end of path component.  */
-               for (end = start; *end && *end != '/'; ++end)
-                       /* Nothing.  */ ;
-               if (end - start == 0)
-                       break;
-               else if (end - start == 1 && start[0] == '.')
-                       /* nothing */ ;
-               else if (end - start == 2 && start[0] == '.' && start[1] == '.') {
-                       /* Back up to previous component, ignore if at root already.  */
-                       if (dest > rpath + 1)
-                               while ((--dest)[-1] != '/') ;
-               } else {
-                       size_t new_size;
-                       if (dest[-1] != '/')
-                               *dest++ = '/';
-                       if (dest + (end - start) >= rpath_limit) {
-                               ptrdiff_t dest_offset = dest - rpath;
-                               new_size = rpath_limit - rpath;
-                               if (end - start + 1 > path_max)
-                                       new_size += end - start + 1;
-                               else
-                                       new_size += path_max;
-                               rpath = dss_realloc(rpath, new_size);
-                               rpath_limit = rpath + new_size;
-                               dest = rpath + dest_offset;
-                       }
-                       memcpy(dest, start, end - start);
-                       dest += end - start;
-                       *dest = '\0';
-                       if (stat(rpath, &st) < 0) {
-                               ret = -ERRNO_TO_DSS_ERROR(errno);
-                               goto error;
-                       }
-                       if (S_ISLNK(st.st_mode)) {
-                               char *buf = alloca(path_max);
-                               size_t len;
-                               if (++num_links > MAXSYMLINKS) {
-                                       ret = -ERRNO_TO_DSS_ERROR(ELOOP);
-                                       goto error;
-                               }
-                               n = readlink(rpath, buf, path_max - 1);
-                               if (n < 0) {
-                                       ret = -ERRNO_TO_DSS_ERROR(errno);
-                                       goto error;
-                               }
-                               buf[n] = '\0';
-                               if (!extra_buf)
-                                       extra_buf = alloca(path_max);
-                               len = strlen(end);
-                               if ((long int) (n + len) >= path_max) {
-                                       ret = -ERRNO_TO_DSS_ERROR(ENAMETOOLONG);
-                                       goto error;
-                               }
-                               /* Careful here, end may be a pointer into extra_buf... */
-                               memmove(&extra_buf[n], end, len + 1);
-                               end = memcpy(extra_buf, buf, n);
-                               if (buf[0] == '/') /* It's an absolute symlink */
-                                       dest = rpath + 1;
-                               else /* Back up to previous component, ignore if at root already: */
-                                       if (dest > rpath + 1)
-                                               while ((--dest)[-1] != '/')
-                                                       ; /* nothing */
-                       } else if (!S_ISDIR(st.st_mode) && *end != '\0') {
-                               ret = -ERRNO_TO_DSS_ERROR(ENOTDIR);
-                               goto error;
-                       }
-               }
-       }
-       if (dest > rpath + 1 && dest[-1] == '/')
-               --dest;
-       *dest = '\0';
-       *resolved_path = rpath;
-       return 1;
- error:
-       free(rpath);
-       *resolved_path = NULL;
-       return ret;
- }
  static int get_key_or_die(const char *config_file)
  {
-       int ret;
-       struct stat statbuf;
-       char *rpath;
        assert(config_file);
-       if (stat(config_file, &statbuf) == 0) {
-               ret = dss_realpath(config_file, &rpath);
-               if (ret < 0) {
-                       DSS_EMERG_LOG(("could not resolve path %s: %s\n", config_file,
-                               dss_strerror(-ret)));
-                       exit(EXIT_FAILURE);
-               }
-               DSS_DEBUG_LOG(("resolved path: %s\n", rpath));
-       } else
-               /*
-                * This happens if the user did not specify a config file, and
-                * the default config file does not exist.  Another (unlikely)
-                * possibility is that the config file was removed between
-                * startup and this call. We don't care about these corner
-                * cases too much and just use the unresolved path in this
-                * case.
-                */
-               rpath = dss_strdup(config_file);
-       ret = super_fast_hash((uint8_t *)rpath, strlen(rpath), 0) >> 1;
-       free(rpath);
-       return ret;
+       return super_fast_hash((uint8_t *)config_file, strlen(config_file), 0) >> 1;
  }
  
  static int mutex_get(key_t key, int flags)