message: use vendored sprintf everywhere
diff: // Version 2.0, that can be found in the LICENSE file.
  #include <cstdarg>
  -#include <cstdio> // for sprintf
  #include <cstdlib> // for abort
  #include <unistd.h>
  #include "common.h"
  -#ifdef __APPLE__
  #include "rpl_printf.c"
  -#endif
  // mutex protecting debug and __mesh_assert_fail to avoid concurrent
  // use of static buffers by multiple threads
  @@ -35,11 +32,7 @@ void mesh::debug(const char *fmt, ...) {
  va_list args;
  va_start(args, fmt);
  -#ifdef __APPLE__
  int len = rpl_vsnprintf(buf, buf_len - 1, fmt, args);
  -#else
  - int len = vsnprintf(buf, buf_len - 1, fmt, args);
  -#endif
  va_end(args);
  buf[buf_len - 1] = 0;
  @@ -64,12 +57,12 @@ void mesh::internal::__mesh_assert_fail(const char *assertion, const char *file,
  va_list args;
  va_start(args, fmt);
  - (void)vsnprintf(usr, usr_len - 1, fmt, args);
  + (void)rpl_vsnprintf(usr, usr_len - 1, fmt, args);
  va_end(args);
  usr[usr_len - 1] = 0;
  - int len = snprintf(buf, buf_len - 1, "%s:%d:%s: ASSERTION '%s' FAILED: %s\n", file, line, func, assertion, usr);
  + int len = rpl_snprintf(buf, buf_len - 1, "%s:%d:%s: ASSERTION '%s' FAILED: %s\n", file, line, func, assertion, usr);
  if (len > 0) {
  auto _ __attribute__((unused)) = write(STDERR_FILENO, buf, len);
  }
  