1                 : /*
       2                 :  * Copyright 2008 The Native Client Authors. All rights reserved.
       3                 :  * Use of this source code is governed by a BSD-style license that can
       4                 :  * be found in the LICENSE file.
       5                 :  */
       6                 : 
       7                 : /*
       8                 :  * NaCl Generic I/O interface.
       9                 :  */
      10                 : #include "native_client/src/include/portability.h"
      11                 : 
      12                 : #include <stdlib.h>
      13                 : 
      14                 : #include "native_client/src/shared/gio/gio.h"
      15                 : 
      16                 : size_t gvprintf(struct Gio *gp,
      17                 :              char const *fmt,
      18          285275 :              va_list    ap) {
      19          285275 :   size_t    bufsz = 1024;
      20          285275 :   char      *buf = malloc(bufsz);
      21                 :   int       rv;
      22                 : 
      23          285275 :   if (!buf) return -1;
      24                 : 
      25          570550 :   while ((rv = vsnprintf(buf, bufsz, fmt, ap)) < 0 || (unsigned) rv >= bufsz) {
      26               0 :     free(buf);
      27               0 :     buf = 0;
      28                 : 
      29                 :     /**
      30                 :      * Since the buffer size wasn't big enough, we want to double it.
      31                 :      * Stop doubling when we reach SIZE_MAX / 2, though, otherwise we
      32                 :      * risk wraparound.
      33                 :      */
      34               0 :     if (bufsz < SIZE_MAX / 2) {
      35               0 :       bufsz *= 2;
      36               0 :       buf = malloc(bufsz);
      37                 :     }
      38                 : 
      39               0 :     if (!buf) {
      40               0 :       return (size_t) -1;
      41                 :     }
      42                 :   }
      43          285275 :   if (rv >= 0) {
      44          285275 :     rv = (int) (*gp->vtbl->Write)(gp, buf, rv);
      45                 :   }
      46          285275 :   free(buf);
      47                 : 
      48          285275 :   return rv;
      49                 : }
      50                 : 
      51                 : 
      52                 : size_t gprintf(struct Gio *gp,
      53          275603 :                char const *fmt, ...) {
      54                 :   va_list ap;
      55                 :   size_t  rv;
      56                 : 
      57          275603 :   va_start(ap, fmt);
      58          275603 :   rv = gvprintf(gp, fmt, ap);
      59          275603 :   va_end(ap);
      60                 : 
      61          275603 :   return rv;
      62                 : }