coredump,basic: generalize O_TMPFILE handling a bit

This moves the O_TMPFILE handling from the coredumping code into common library
code, and generalizes it as open_tmpfile_linkable() + link_tmpfile(). The
existing open_tmpfile() function (which creates an unlinked temporary file that
cannot be linked into the fs) is renamed to open_tmpfile_unlinkable(), to make
the distinction clear. Thus, code may now choose between:

 a) open_tmpfile_linkable() + link_tmpfile()
 b) open_tmpfile_unlinkable()

Depending on whether they want a file that may be linked back into the fs later
on or not.

In a later commit we should probably convert fopen_temporary() to make use of
open_tmpfile_linkable().

Followup for: #3065

1 files changed, 3 insertions, 1 deletions

diff --git a/src/journal-remote/journal-gatewayd.c b/src/journal-remote/journal-gatewayd.c
index 60d897758b..4ad9184993 100644
--- a/src/journal-remote/journal-gatewayd.c
+++ b/src/journal-remote/journal-gatewayd.c
@@ -122,12 +122,14 @@ static int open_journal(RequestMeta *m) {
 }
 
 static int request_meta_ensure_tmp(RequestMeta *m) {
+        assert(m);
+
         if (m->tmp)
                 rewind(m->tmp);
         else {
                 int fd;
 
-                fd = open_tmpfile("/tmp", O_RDWR|O_CLOEXEC);
+                fd = open_tmpfile_unlinkable("/tmp", O_RDWR|O_CLOEXEC);
                 if (fd < 0)
                         return fd;