Prefer other types to int in extract.c

* src/extract.c (fd_chmod, extract_chdir, open_output_file)
(extract_file, extract_link, extract_symlink, extract_node)
(extract_fifo, tar_extractor_t, pepare_to_extract): Prefer char to
int for typeflag, since it’s a char.  All uses changed.
(fd_chmod): Use clearer code for errno.
(extract_dir, extract_file, create_placeholder_file, extract_link)
(extract_symlink, extract_node, extract_fifo, tar_extractor_t):
Return bool true for success, false for failure.  All uses changed.
(open_output_file): Prefer bool for boolean.
(prepare_to_extract): Simplify by returning the extractor a null
pointer, rather than storing through a pointer to an extractor.

src/extract.c

@@ -272,9 +272,9 @@ fd_i_chmod (int fd, char const *file, mode_t mode, int atflag)
    notation.
  */
 static int
-fd_chmod(int fd, char const *file_name, int mode, int atflag, int typeflag)
+fd_chmod (int fd, char const *file_name, int mode, int atflag, char typeflag)
 {
-  int chmod_errno = fd_i_chmod (fd, file_name, mode, atflag) == 0 ? 0 : errno;
+  int chmod_errno = fd_i_chmod (fd, file_name, mode, atflag) < 0 ? errno : 0;
 
   /* On Solaris, chmod may fail if we don't have PRIV_ALL, because
      setuid-root files would otherwise be a backdoor.  See
@@ -283,7 +283,7 @@ fd_chmod(int fd, char const *file_name, int mode, int atflag, int typeflag)
   if (chmod_errno == EPERM && (mode & S_ISUID)
       && priv_set_restore_linkdir () == 0)
     {
-      chmod_errno = fd_i_chmod (fd, file_name, mode, atflag) == 0 ? 0 : errno;
+      chmod_errno = fd_i_chmod (fd, file_name, mode, atflag) < 0 ? errno : 0;
       priv_set_remove_linkdir ();
     }
 
@@ -293,7 +293,7 @@ fd_chmod(int fd, char const *file_name, int mode, int atflag, int typeflag)
      supported and if the file is not a symlink.  This
      introduces a race, alas.  */
   if (atflag && typeflag != SYMTYPE && ! implemented (chmod_errno))
-    chmod_errno = fd_i_chmod (fd, file_name, mode, 0) == 0 ? 0 : errno;
+    chmod_errno = fd_i_chmod (fd, file_name, mode, 0) < 0 ? errno : 0;
 
   if (chmod_errno && (typeflag != SYMTYPE || implemented (chmod_errno)))
     {
@@ -1061,8 +1061,8 @@ safe_dir_mode (struct stat const *st)
 
 /* Extractor functions for various member types */
 
-static int
+static bool
-extract_dir (char *file_name, int typeflag)
+extract_dir (char *file_name, char typeflag)
 {
   int status;
   mode_t mode;
@@ -1114,7 +1114,7 @@ extract_dir (char *file_name, int typeflag)
 
 	      if (keep_directory_symlink_option
 		  && is_directory_link (file_name, &st))
-		return 0;
+		return true;
 
 	      if ((st.st_mode != 0 && fstatat_flags == 0)
 		  || deref_stat (file_name, &st) == 0)
@@ -1127,7 +1127,7 @@ extract_dir (char *file_name, int typeflag)
 		      if (interdir_made)
 			{
 			  repair_delayed_set_stat (file_name, &st);
-			  return 0;
+			  return true;
 			}
 		      else if (old_files_option == NO_OVERWRITE_DIR_OLD_FILES)
 			{
@@ -1179,7 +1179,7 @@ extract_dir (char *file_name, int typeflag)
 	  if (errno != EEXIST)
 	    {
 	      mkdir_error (file_name);
-	      return 1;
+	      return false;
 	    }
 	  break;
 	}
@@ -1192,13 +1192,13 @@ extract_dir (char *file_name, int typeflag)
     delay_set_stat (file_name, &current_stat_info,
 		    current_mode, current_mode_mask,
 		    current_stat_info.stat.st_mode, atflag);
-  return status;
+  return status == 0;
 }
 
 
 
 static int
-open_output_file (char const *file_name, int typeflag, mode_t mode,
+open_output_file (char const *file_name, char typeflag, mode_t mode,
                   int file_created, mode_t *current_mode,
                   mode_t *current_mode_mask)
 {
@@ -1214,11 +1214,11 @@ open_output_file (char const *file_name, int typeflag, mode_t mode,
 
   if (typeflag == CONTTYPE)
     {
-      static int conttype_diagnosed;
+      static bool conttype_diagnosed;
 
       if (!conttype_diagnosed)
 	{
-	  conttype_diagnosed = 1;
+	  conttype_diagnosed = true;
 	  warnopt (WARN_CONTIGUOUS_CAST, 0,
 		   _("Extracting contiguous files as regular files"));
 	}
@@ -1270,8 +1270,8 @@ open_output_file (char const *file_name, int typeflag, mode_t mode,
   return fd;
 }
 
-static int
+static bool
-extract_file (char *file_name, int typeflag)
+extract_file (char *file_name, char typeflag)
 {
   int fd;
   off_t size;
@@ -1291,7 +1291,7 @@ extract_file (char *file_name, int typeflag)
       if (fd < 0)
 	{
 	  skip_member ();
-	  return 0;
+	  return true;
 	}
     }
   else
@@ -1315,9 +1315,9 @@ extract_file (char *file_name, int typeflag)
 	    {
 	      skip_member ();
 	      if (recover == RECOVER_SKIP)
-		return 0;
+		return true;
 	      open_error (file_name);
-	      return 1;
+	      return false;
 	    }
 	}
     }
@@ -1368,7 +1368,7 @@ extract_file (char *file_name, int typeflag)
      it doesn't exist, or we don't want to touch it anyway.  */
 
   if (to_stdout_option)
-    return 0;
+    return true;
 
   if (! to_command_option)
     set_stat (file_name, &current_stat_info, fd,
@@ -1383,7 +1383,7 @@ extract_file (char *file_name, int typeflag)
   if (to_command_option)
     sys_wait_command ();
 
-  return status;
+  return status == 0;
 }
 
 /* Return true if NAME is a delayed link.  This can happen only if the link
@@ -1423,7 +1423,7 @@ find_delayed_link_source (char const *name)
    process.
 */
 
-static int
+static bool
 create_placeholder_file (char *file_name, bool is_symlink, bool *interdir_made)
 {
   int fd;
@@ -1437,7 +1437,7 @@ create_placeholder_file (char *file_name, bool is_symlink, bool *interdir_made)
 	     that the link being extracted is a duplicate of an already
 	     processed one.  Skip it.
 	   */
-	  return 0;
+	  return true;
 	}
 
       switch (maybe_recoverable (file_name, false, interdir_made))
@@ -1446,11 +1446,11 @@ create_placeholder_file (char *file_name, bool is_symlink, bool *interdir_made)
 	  continue;
 
 	case RECOVER_SKIP:
-	  return 0;
+	  return true;
 
 	case RECOVER_NO:
 	  open_error (file_name);
-	  return -1;
+	  return false;
 	}
       }
 
@@ -1508,14 +1508,14 @@ create_placeholder_file (char *file_name, bool is_symlink, bool *interdir_made)
       if ((h = find_direct_ancestor (file_name)) != NULL)
 	mark_after_links (h);
 
-      return 0;
+      return true;
     }
 
-  return -1;
+  return false;
 }
 
-static int
+static bool
-extract_link (char *file_name, MAYBE_UNUSED int typeflag)
+extract_link (char *file_name, MAYBE_UNUSED char typeflag)
 {
   bool interdir_made = false;
   char const *link_name;
@@ -1555,7 +1555,7 @@ extract_link (char *file_name, MAYBE_UNUSED int typeflag)
 		}
 	    }
 
-	  return 0;
+	  return true;
 	}
       else if ((e == EEXIST && strcmp (link_name, file_name) == 0)
 	       || ((fstatat (chdir_fd, link_name, &st1, AT_SYMLINK_NOFOLLOW)
@@ -1564,7 +1564,7 @@ extract_link (char *file_name, MAYBE_UNUSED int typeflag)
 		       == 0)
 		   && st1.st_dev == st2.st_dev
 		   && st1.st_ino == st2.st_ino))
-	return 0;
+	return true;
 
       errno = e;
     }
@@ -1572,17 +1572,17 @@ extract_link (char *file_name, MAYBE_UNUSED int typeflag)
 	 == RECOVER_OK);
 
   if (rc == RECOVER_SKIP)
-    return 0;
+    return true;
   if (!(incremental_option && errno == EEXIST))
     {
       link_error (link_name, file_name);
-      return 1;
+      return false;
     }
-  return 0;
+  return true;
 }
 
-static int
+static bool
-extract_symlink (char *file_name, MAYBE_UNUSED int typeflag)
+extract_symlink (char *file_name, MAYBE_UNUSED char typeflag)
 {
   bool interdir_made = false;
 
@@ -1598,7 +1598,7 @@ extract_symlink (char *file_name, MAYBE_UNUSED int typeflag)
 	continue;
 
       case RECOVER_SKIP:
-	return 0;
+	return true;
 
       case RECOVER_NO:
 	if (!implemented (errno))
@@ -1614,17 +1614,17 @@ extract_symlink (char *file_name, MAYBE_UNUSED int typeflag)
 	    return extract_link (file_name, typeflag);
 	  }
 	symlink_error (current_stat_info.link_name, file_name);
-	return -1;
+	return false;
       }
 
   set_stat (file_name, &current_stat_info, -1, 0, 0,
 	    SYMTYPE, false, AT_SYMLINK_NOFOLLOW);
-  return 0;
+  return true;
 }
 
 #if S_IFCHR || S_IFBLK
-static int
+static bool
-extract_node (char *file_name, int typeflag)
+extract_node (char *file_name, char typeflag)
 {
   bool interdir_made = false;
   mode_t mode = (current_stat_info.stat.st_mode & (MODE_RWX | S_IFBLK | S_IFCHR)
@@ -1638,23 +1638,23 @@ extract_node (char *file_name, int typeflag)
 	continue;
 
       case RECOVER_SKIP:
-	return 0;
+	return true;
 
       case RECOVER_NO:
 	mknod_error (file_name);
-	return -1;
+	return false;
       }
 
   set_stat (file_name, &current_stat_info, -1,
 	    mode & ~ current_umask, MODE_RWX,
 	    typeflag, false, AT_SYMLINK_NOFOLLOW);
-  return 0;
+  return true;
 }
 #endif
 
 #if HAVE_MKFIFO || defined mkfifo
-static int
+static bool
-extract_fifo (char *file_name, int typeflag)
+extract_fifo (char *file_name, char typeflag)
 {
   bool interdir_made = false;
   mode_t mode = (current_stat_info.stat.st_mode & MODE_RWX
@@ -1667,31 +1667,31 @@ extract_fifo (char *file_name, int typeflag)
 	continue;
 
       case RECOVER_SKIP:
-	return 0;
+	return true;
 
       case RECOVER_NO:
 	mkfifo_error (file_name);
-	return -1;
+	return false;
       }
 
   set_stat (file_name, &current_stat_info, -1,
 	    mode & ~ current_umask, MODE_RWX,
 	    typeflag, false, AT_SYMLINK_NOFOLLOW);
-  return 0;
+  return true;
 }
 #endif
 
-typedef int (*tar_extractor_t) (char *file_name, int typeflag);
+typedef bool (*tar_extractor_t) (char *file_name, char typeflag);
 
 
 /* Prepare to extract a file. Find extractor function.
-   Return true to proceed with the extraction, false to skip the current
+   Return an extractor to proceed with the extraction,
-   member.  */
+   a null pointer to skip the current member.  */
 
-static bool
+static tar_extractor_t
-prepare_to_extract (char const *file_name, int typeflag, tar_extractor_t *fun)
+prepare_to_extract (char const *file_name, char typeflag)
 {
-  tar_extractor_t extractor = NULL;
+  tar_extractor_t extractor;
 
   /* Select the extractor */
   switch (typeflag)
@@ -1705,10 +1705,8 @@ prepare_to_extract (char const *file_name, int typeflag, tar_extractor_t *fun)
     case CONTTYPE:
       /* Appears to be a file.  But BSD tar uses the convention that a slash
 	 suffix means a directory.  */
-      if (current_stat_info.had_trailing_slash)
+      extractor = (current_stat_info.had_trailing_slash
-	extractor = extract_dir;
+		   ? extract_dir : extract_file);
-      else
-	extractor = extract_file;
       break;
 
     case SYMTYPE:
@@ -1747,17 +1745,17 @@ prepare_to_extract (char const *file_name, int typeflag, tar_extractor_t *fun)
       break;
 
     case GNUTYPE_VOLHDR:
-      return false;
+      return NULL;
 
     case GNUTYPE_MULTIVOL:
       paxerror (0, _("%s: Cannot extract -- file is continued from another volume"),
 		quotearg_colon (current_stat_info.file_name));
-      return false;
+      return NULL;
 
     case GNUTYPE_LONGNAME:
     case GNUTYPE_LONGLINK:
       paxerror (0, _("Unexpected long name header"));
-      return false;
+      return NULL;
 
     default:
       warnopt (WARN_UNKNOWN_CAST, 0,
@@ -1769,7 +1767,7 @@ prepare_to_extract (char const *file_name, int typeflag, tar_extractor_t *fun)
   if (to_stdout_option || to_command_option)
     {
       if (extractor != extract_file)
-	return false;
+	return NULL;
     }
   else
     {
@@ -1783,7 +1781,7 @@ prepare_to_extract (char const *file_name, int typeflag, tar_extractor_t *fun)
 	      && errno && errno != ENOENT)
 	    {
 	      unlink_error (file_name);
-	      return false;
+	      return NULL;
 	    }
 	  break;
 
@@ -1792,7 +1790,7 @@ prepare_to_extract (char const *file_name, int typeflag, tar_extractor_t *fun)
 	    {
 	      warnopt (WARN_IGNORE_NEWER, 0, _("Current %s is newer or same age"),
 		       quote (file_name));
-	      return false;
+	      return NULL;
 	    }
 	  break;
 
@@ -1800,9 +1798,7 @@ prepare_to_extract (char const *file_name, int typeflag, tar_extractor_t *fun)
 	  break;
 	}
     }
-  *fun = extractor;
+  return extractor;
-
-  return true;
 }
 
 /* Extract a file from the archive.  */
@@ -1810,7 +1806,6 @@ void
 extract_archive (void)
 {
   char typeflag;
-  tar_extractor_t fun;
   bool skip_dotdot_name;
 
   fatal_exit_hook = extract_finish;
@@ -1859,12 +1854,14 @@ extract_archive (void)
 
   /* Extract the archive entry according to its type.  */
   /* KLUDGE */
-  typeflag = sparse_member_p (&current_stat_info) ?
+  typeflag = (sparse_member_p (&current_stat_info)
-                  GNUTYPE_SPARSE : current_header->header.typeflag;
+	      ? GNUTYPE_SPARSE : current_header->header.typeflag);
 
-  if (prepare_to_extract (current_stat_info.file_name, typeflag, &fun))
+  tar_extractor_t fun = prepare_to_extract (current_stat_info.file_name,
+					    typeflag);
+  if (fun)
     {
-      if (fun (current_stat_info.file_name, typeflag) == 0)
+      if (fun (current_stat_info.file_name, typeflag))
 	return;
     }
   else