[Libguestfs] [PATCH 17/67] resize: Mark isatty function as "noalloc".

From: "Richard W.M. Jones" <rjones(a)redhat.com&gt; This turns it into an ordinary C call without the unnecessary [in this case] GC frame overhead. See: http://camltastic.blogspot.co.uk/2008/08/tip-calling-c-functions-directly... (cherry picked from commit 3d39549ded3e05df929547bb65ce620e6487a81b) --- resize/tTY.ml | 2 +- resize/tty-c.c | 11 +++++++---- 2 files changed, 8 insertions(+), 5 deletions(-) diff --git a/resize/tTY.ml b/resize/tTY.ml index 32c1f54..80f0e1e 100644 --- a/resize/tTY.ml +++ b/resize/tTY.ml @@ -16,4 +16,4 @@ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. *) -external isatty_stdout : unit -> bool = "virt_resize_isatty_stdout" +external isatty_stdout : unit -> bool = "virt_resize_isatty_stdout" "noalloc" diff --git a/resize/tty-c.c b/resize/tty-c.c index 040a132..64fa884 100644 --- a/resize/tty-c.c +++ b/resize/tty-c.c @@ -25,11 +25,14 @@ #include <caml/memory.h> #include <caml/mlvalues.h> -/* RHEL 5-era ocaml didn't have Unix.isatty. */ +/* RHEL 5-era ocaml didn't have Unix.isatty. + * + * Note this function is marked as "noalloc" so it must not call any + * OCaml allocation functions: + * http://camltastic.blogspot.co.uk/2008/08/tip-calling-c-functions-directly... + */ value virt_resize_isatty_stdout (value unitv) { - CAMLparam1 (unitv); - - CAMLreturn (isatty (1) ? Val_true : Val_false); + return isatty (1) ? Val_true : Val_false; } -- 1.8.3.1