From d3be43fcc5165b7680c9073438ad60a3652c1703 Mon Sep 17 00:00:00 2001 From: Ryan Lortie Date: Mon, 3 Jun 2013 15:43:01 -0400 Subject: [PATCH] g_file_set_contents(): use posix_fallocate() Extents-based filesystems like knowing in advance how much data will be written to a file in order to prevent fragmentation. If we have it, use posix_fallocate() before writing data in g_file_set_contents(). https://bugzilla.gnome.org/show_bug.cgi?id=701560 --- configure.ac | 2 +- glib/gfileutils.c | 7 +++++++ 2 files changed, 8 insertions(+), 1 deletion(-) diff --git a/configure.ac b/configure.ac index eb37a4d..53b38bc 100644 --- a/configure.ac +++ b/configure.ac @@ -1056,7 +1056,7 @@ AC_MSG_RESULT($glib_ssize_type) # Check for some functions AC_CHECK_FUNCS(lstat strerror strsignal memmove vsnprintf stpcpy strcasecmp strncasecmp poll getcwd vasprintf setenv unsetenv getc_unlocked readlink symlink fdwalk memmem) AC_CHECK_FUNCS(chown lchmod lchown fchmod fchown link utimes getgrgid getpwuid getresuid) -AC_CHECK_FUNCS(getmntent_r setmntent endmntent hasmntopt getfsstat getvfsstat) +AC_CHECK_FUNCS(getmntent_r setmntent endmntent hasmntopt getfsstat getvfsstat posix_fallocate) # Check for high-resolution sleep functions AC_CHECK_FUNCS(splice) AC_CHECK_FUNCS(prlimit) diff --git a/glib/gfileutils.c b/glib/gfileutils.c index 5ef87a9..d0c1fc9 100644 --- a/glib/gfileutils.c +++ b/glib/gfileutils.c @@ -1059,6 +1059,13 @@ write_to_temp_file (const gchar *contents, if (length > 0) { gsize n_written; + +#ifdef HAVE_POSIX_FALLOCATE + /* We do this on a 'best effort' basis... It may not be supported + * on the underlying filesystem. + */ + (void) posix_fallocate (fd, 0, length); +#endif errno = 0; -- 2.7.4