[Libguestfs] [PATCH 08/10] daemon: move make_exclude_from_file as common helper

[Pino Toscano]

It will be useful also for APIs different than tar-out, so move it to
guestfsd.c, and add it a parameter to specify the function name that
invoked it.

This is mostly code motion.
---
 daemon/daemon.h   |  2 ++
 daemon/guestfsd.c | 62 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 daemon/tar.c      | 58 +--------------------------------------------------
 3 files changed, 65 insertions(+), 57 deletions(-)

diff --git a/daemon/daemon.h b/daemon/daemon.h
index 8097bfc..793074d 100644
--- a/daemon/daemon.h
+++ b/daemon/daemon.h
@@ -147,6 +147,8 @@ extern int random_name (char *template);
 
 extern char *get_random_uuid (void);
 
+extern char *make_exclude_from_file (const char *function, char *const *excludes);
+
 extern int asprintf_nowarn (char **strp, const char *fmt, ...);
 
 /*-- in names.c (auto-generated) --*/
diff --git a/daemon/guestfsd.c b/daemon/guestfsd.c
index 57e3886..a848fe1 100644
--- a/daemon/guestfsd.c
+++ b/daemon/guestfsd.c
@@ -1247,6 +1247,68 @@ get_random_uuid (void)
 
 }
 
+/**
+ * Turn list C<excludes> into a temporary file, and return a string
+ * containing the temporary file name.  Caller must unlink the file
+ * and free the string.
+ *
+ * C<function> is the function that invoked this helper, and it is
+ * used mainly for errors/debugging.
+ */
+char *
+make_exclude_from_file (const char *function, char *const *excludes)
+{
+  size_t i;
+  int fd;
+  char template[] = "/tmp/excludesXXXXXX";
+  char *ret;
+
+  fd = mkstemp (template);
+  if (fd == -1) {
+    reply_with_perror ("mkstemp");
+    return NULL;
+  }
+
+  for (i = 0; excludes[i] != NULL; ++i) {
+    if (strchr (excludes[i], '\n')) {
+      reply_with_error ("%s: excludes file patterns cannot contain \\n character",
+                        function);
+      goto error;
+    }
+
+    if (xwrite (fd, excludes[i], strlen (excludes[i])) == -1 ||
+        xwrite (fd, "\n", 1) == -1) {
+      reply_with_perror ("write");
+      goto error;
+    }
+
+    if (verbose)
+      fprintf (stderr, "%s: adding excludes pattern '%s'\n",
+               function, excludes[i]);
+  }
+
+  if (close (fd) == -1) {
+    reply_with_perror ("close");
+    fd = -1;
+    goto error;
+  }
+  fd = -1;
+
+  ret = strdup (template);
+  if (ret == NULL) {
+    reply_with_perror ("strdup");
+    goto error;
+  }
+
+  return ret;
+
+ error:
+  if (fd >= 0)
+    close (fd);
+  unlink (template);
+  return NULL;
+}
+
 void
 cleanup_free_mountable (mountable_t *mountable)
 {
diff --git a/daemon/tar.c b/daemon/tar.c
index ea8b342..c23aa0a 100644
--- a/daemon/tar.c
+++ b/daemon/tar.c
@@ -268,62 +268,6 @@ do_txz_in (const char *dir)
   return do_tar_in (dir, "xz", 0, 0, 0);
 }
 
-/* Turn list 'excludes' into a temporary file, and return a string
- * containing the temporary file name.  Caller must unlink the file
- * and free the string.
- */
-static char *
-make_exclude_from_file (char *const *excludes)
-{
-  size_t i;
-  int fd;
-  char template[] = "/tmp/excludesXXXXXX";
-  char *ret;
-
-  fd = mkstemp (template);
-  if (fd == -1) {
-    reply_with_perror ("mkstemp");
-    return NULL;
-  }
-
-  for (i = 0; excludes[i] != NULL; ++i) {
-    if (strchr (excludes[i], '\n')) {
-      reply_with_error ("tar-out: excludes file patterns cannot contain \\n character");
-      goto error;
-    }
-
-    if (xwrite (fd, excludes[i], strlen (excludes[i])) == -1 ||
-        xwrite (fd, "\n", 1) == -1) {
-      reply_with_perror ("write");
-      goto error;
-    }
-
-    if (verbose)
-      fprintf (stderr, "tar-out: adding excludes pattern '%s'\n", excludes[i]);
-  }
-
-  if (close (fd) == -1) {
-    reply_with_perror ("close");
-    fd = -1;
-    goto error;
-  }
-  fd = -1;
-
-  ret = strdup (template);
-  if (ret == NULL) {
-    reply_with_perror ("strdup");
-    goto error;
-  }
-
-  return ret;
-
- error:
-  if (fd >= 0)
-    close (fd);
-  unlink (template);
-  return NULL;
-}
-
 /* Has one FileOut parameter. */
 /* Takes optional arguments, consult optargs_bitmask. */
 int
@@ -367,7 +311,7 @@ do_tar_out (const char *dir, const char *compress, int numericowner,
     numericowner = 0;
 
   if ((optargs_bitmask & GUESTFS_TAR_OUT_EXCLUDES_BITMASK)) {
-    exclude_from_file = make_exclude_from_file (excludes);
+    exclude_from_file = make_exclude_from_file ("tar-out", excludes);
     if (!exclude_from_file)
       return -1;
   }
-- 
2.9.3