Allow using snprintf() instead of sprintf() in wrappers

We aim to produce code that works with C90 or C++98 so we can't
assume snprintf() is available, but it almost always is (even
on systems from before it was standardised) so having a way to
use it is helpful.

Enable this automatically if the compiler claims conformance
with at least C90 or C++98 and check SWIG_HAVE_SNPRINTF to allow
turning on manually, but disable if SWIG_NO_SNPRINTF if defined.

The fallback is to call sprintf() without a buffer size check -
checking after the call is really shutting the stable door after
the horse has bolted, and most of our uses either have a fixed maximum
possible size or dynamically allocate a buffer that's large enough.

Fixes: #2502 (sprintf deprecation warnings on macos)
Fixes: #2548

1 files changed, 5 insertions, 5 deletions

diff --git a/Lib/ocaml/cstring.i b/Lib/ocaml/cstring.i
index f1190ad5c..8b72be9d0 100644
--- a/Lib/ocaml/cstring.i
+++ b/Lib/ocaml/cstring.i
@@ -25,7 +25,7 @@
  *
  *     %cstring_bounded_output(char *outx, 512);
  *     void foo(char *outx) {
- *         sprintf(outx,"blah blah\n");
+ *         strcpy(outx,"blah blah\n");
  *     }
  *
  */
@@ -144,7 +144,7 @@
  *
  *     %cstring_output_maxsize(char *outx, int max) {
  *     void foo(char *outx, int max) {
- *         sprintf(outx,"blah blah\n");
+ *         strcpy(outx,"blah blah\n");
  *     }
  */
 
@@ -175,7 +175,7 @@
  *
  *     %cstring_output_maxsize(char *outx, int *max) {
  *     void foo(char *outx, int *max) {
- *         sprintf(outx,"blah blah\n");
+ *         strcpy(outx,"blah blah\n");
  *         *max = strlen(outx);  
  *     }
  */
@@ -213,7 +213,7 @@
  *     %cstring_output_allocated(char **outx, free($1));
  *     void foo(char **outx) {
  *         *outx = (char *) malloc(512);
- *         sprintf(outx,"blah blah\n");
+ *         strcpy(outx,"blah blah\n");
  *     }
  */
 
@@ -241,7 +241,7 @@
  *     %cstring_output_allocated(char **outx, int *sz, free($1));
  *     void foo(char **outx, int *sz) {
  *         *outx = (char *) malloc(512);
- *         sprintf(outx,"blah blah\n");
+ *         strcpy(outx,"blah blah\n");
  *         *sz = strlen(outx);
  *     }
  */