stdio/FreeBSD/fread.c.patch

   1 --- fread.c.orig        2008-08-29 21:58:50.000000000 -0700
   2 +++ fread.c     2008-09-02 02:18:06.000000000 -0700
   3 @@ -55,7 +55,7 @@ fread(buf, size, count, fp)
   4  {
   5         size_t resid;
   6         char *p;
   7 -       int r;
   8 +       int r, ret;
   9         size_t total;
  10
  11         /*
  12 @@ -71,21 +71,70 @@ fread(buf, size, count, fp)
  13                 fp->_r = 0;
  14         total = resid;
  15         p = buf;
  16 +       /* first deal with anything left in buffer, plus any ungetc buffers */
  17         while (resid > (r = fp->_r)) {
  18                 (void)memcpy((void *)p, (void *)fp->_p, (size_t)r);
  19                 fp->_p += r;
  20                 /* fp->_r = 0 ... done in __srefill */
  21                 p += r;
  22                 resid -= r;
  23 -               if (__srefill(fp)) {
  24 +               if ((ret = __srefill0(fp)) > 0)
  25 +                       break;
  26 +               else if (ret) {
  27                         /* no more input: return partial result */
  28                         FUNLOCKFILE(fp);
  29                         return ((total - resid) / size);
  30                 }
  31         }
  32 -       (void)memcpy((void *)p, (void *)fp->_p, resid);
  33 -       fp->_r -= resid;
  34 -       fp->_p += resid;
  35 +       /*
  36 +        * 5980080: don't use optimization if __SMBF not set (meaning setvbuf
  37 +        * was called, and the buffer belongs to the user).
  38 +        * 6180417: but for unbuffered (__SMBF is not set), so specifically
  39 +        * test for it.
  40 +        */
  41 +       if ((fp->_flags & (__SMBF | __SNBF)) && resid > fp->_bf._size) {
  42 +               struct __sbuf save;
  43 +               size_t n;
  44 +
  45 +               save = fp->_bf;
  46 +               fp->_bf._base = p;
  47 +               fp->_bf._size = resid;
  48 +               while (fp->_bf._size > 0) {
  49 +                       if ((ret = __srefill1(fp)) != 0) {
  50 +                               /* no more input: return partial result */
  51 +                               resid = fp->_bf._size;
  52 +                               fp->_bf = save;
  53 +                               fp->_p = fp->_bf._base;
  54 +                               /* fp->_r = 0;  already set in __srefill1 */
  55 +                               FUNLOCKFILE(fp);
  56 +                               return ((total - resid) / size);
  57 +                       }
  58 +                       fp->_bf._base += fp->_r;
  59 +                       fp->_bf._size -= fp->_r;
  60 +               }
  61 +               fp->_bf = save;
  62 +               n = fp->_bf._size * ((resid - 1) / fp->_bf._size);
  63 +               r = resid - n;
  64 +               (void)memcpy((void *)fp->_bf._base, (void *)(p + n), (size_t)r);
  65 +               fp->_p = fp->_bf._base + r;
  66 +               fp->_r = 0;
  67 +       } else {
  68 +               while (resid > (r = fp->_r)) {
  69 +                       (void)memcpy((void *)p, (void *)fp->_p, (size_t)r);
  70 +                       fp->_p += r;
  71 +                       /* fp->_r = 0 ... done in __srefill */
  72 +                       p += r;
  73 +                       resid -= r;
  74 +                       if (__srefill1(fp)) {
  75 +                               /* no more input: return partial result */
  76 +                               FUNLOCKFILE(fp);
  77 +                               return ((total - resid) / size);
  78 +                       }
  79 +               }
  80 +               (void)memcpy((void *)p, (void *)fp->_p, resid);
  81 +               fp->_r -= resid;
  82 +               fp->_p += resid;
  83 +       }
  84         FUNLOCKFILE(fp);
  85         return (count);
  86  }