In the --fast-read mode send SIGTERM to decompressor once we have extracted

all files we have been asked for. This vastly improves performance of
pkg_add(1), because usually it only extract +CONTENTS file in --fast-read
mode, checks it and only then extracts full content of tarball in normal
mode. Without this patch, it have had to decompress the tarball twice,
effectively doubling consumed CPU time.

MFC after:	1 week

1 files changed, 10 insertions, 6 deletions

diff --git a/contrib/tar/src/buffer.c b/contrib/tar/src/buffer.c
index d20f5aa2d169..2749aadecde6 100644
--- a/contrib/tar/src/buffer.c
+++ b/contrib/tar/src/buffer.c
@@ -1332,6 +1332,9 @@ close_archive (void)
      might become clever enough to just stop working, once there is no more
      work to do, we might have to revise this area in such time.  */
 
+  if (fast_read_option && namelist_freed)
+    kill(child_pid, SIGTERM);
+
   if (access_mode == ACCESS_READ
       && ! _isrmt (archive)
       && (S_ISFIFO (archive_stat.st_mode) || S_ISSOCK (archive_stat.st_mode)))
@@ -1358,12 +1361,13 @@ close_archive (void)
 	    break;
 	  }
 
-      if (WIFSIGNALED (wait_status))
-	ERROR ((0, 0, _("Child died with signal %d"),
-		WTERMSIG (wait_status)));
-      else if (WEXITSTATUS (wait_status) != 0)
-	ERROR ((0, 0, _("Child returned status %d"),
-		WEXITSTATUS (wait_status)));
+      if (!fast_read_option || !namelist_freed)
+        if (WIFSIGNALED (wait_status))
+	  ERROR ((0, 0, _("Child died with signal %d"),
+		  WTERMSIG (wait_status)));
+        else if (WEXITSTATUS (wait_status) != 0)
+	  ERROR ((0, 0, _("Child returned status %d"),
+		  WEXITSTATUS (wait_status)));
     }
 #endif /* !MSDOS */