int streambuf::xsgetn(char* s, int n)
{
register int more = n;
for (;;) {
int count = _egptr - _gptr; // Data available.
if (count > 0) {
if (count > more)
count = more;
if (count > 20) {
memcpy(s, _gptr, count);
s += count;
_gptr += count;
}
else if (count <= 0)
count = 0;
else {
register char *p = _gptr;
for (register int i = count; --i >= 0; ) *s++ = *p++;
_gptr = p;
}
more -= count;
}
if (more == 0 || __underflow(this) == EOF)
break;
}
return n - more;
}
int streambuf::ignore(int n)
{
register int more = n;
for (;;) {
int count = _egptr - _gptr; // Data available.
if (count > 0) {
if (count > more)
count = more;
_gptr += count;
more -= count;
}
if (more == 0 || __underflow(this) == EOF)
break;
}
return n - more;
}
_IO_size_t
_IO_default_xsgetn (_IO_FILE *fp, void *data, _IO_size_t n)
{
_IO_size_t more = n;
char *s = (char*) data;
for (;;)
{
/* Data available. */
if (fp->_IO_read_ptr < fp->_IO_read_end)
{
_IO_size_t count = fp->_IO_read_end - fp->_IO_read_ptr;
if (count > more)
count = more;
if (count > 20)
{
#ifdef _LIBC
s = __mempcpy (s, fp->_IO_read_ptr, count);
#else
memcpy (s, fp->_IO_read_ptr, count);
s += count;
#endif
fp->_IO_read_ptr += count;
}
else if (count)
{
char *p = fp->_IO_read_ptr;
int i = (int) count;
while (--i >= 0)
*s++ = *p++;
fp->_IO_read_ptr = p;
}
more -= count;
}
if (more == 0 || __underflow (fp) == EOF)
break;
}
return n - more;
}
_IO_size_t
_IO_file_xsgetn (_IO_FILE *fp, void *data, _IO_size_t n)
{
_IO_size_t want, have;
_IO_ssize_t count;
char *s = data;
want = n;
if (fp->_IO_buf_base == NULL)
{
/* Maybe we already have a push back pointer. */
if (fp->_IO_save_base != NULL)
{
free (fp->_IO_save_base);
fp->_flags &= ~_IO_IN_BACKUP;
}
_IO_doallocbuf (fp);
}
while (want > 0)
{
have = fp->_IO_read_end - fp->_IO_read_ptr;
if (want <= have)
{
memcpy (s, fp->_IO_read_ptr, want);
fp->_IO_read_ptr += want;
want = 0;
}
else
{
if (have > 0)
{
#ifdef _LIBC
s = __mempcpy (s, fp->_IO_read_ptr, have);
#else
memcpy (s, fp->_IO_read_ptr, have);
s += have;
#endif
want -= have;
fp->_IO_read_ptr += have;
}
/* Check for backup and repeat */
if (_IO_in_backup (fp))
{
_IO_switch_to_main_get_area (fp);
continue;
}
/* If we now want less than a buffer, underflow and repeat
the copy. Otherwise, _IO_SYSREAD directly to
the user buffer. */
if (fp->_IO_buf_base
&& want < (size_t) (fp->_IO_buf_end - fp->_IO_buf_base))
{
if (__underflow (fp) == EOF)
break;
continue;
}
/* These must be set before the sysread as we might longjmp out
waiting for input. */
_IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base);
_IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base);
/* Try to maintain alignment: read a whole number of blocks. */
count = want;
if (fp->_IO_buf_base)
{
_IO_size_t block_size = fp->_IO_buf_end - fp->_IO_buf_base;
if (block_size >= 128)
count -= want % block_size;
}
count = _IO_SYSREAD (fp, s, count);
if (count <= 0)
{
if (count == 0)
fp->_flags |= _IO_EOF_SEEN;
else
fp->_flags |= _IO_ERR_SEEN;
break;
}
s += count;
want -= count;
if (fp->_offset != _IO_pos_BAD)
_IO_pos_adjust (fp->_offset, count);
}
}
return n - want;
}
_IO_ssize_t
_IO_getdelim(char **lineptr, _IO_size_t *n, int delimiter, _IO_FILE *fp)
{
_IO_ssize_t result;
_IO_ssize_t cur_len = 0;
_IO_ssize_t len;
if (lineptr == NULL || n == NULL)
{
MAYBE_SET_EINVAL;
return -1;
}
CHECK_FILE (fp, -1);
_IO_acquire_lock(fp);
if (_IO_ferror_unlocked(fp))
{
result = -1;
goto unlock_return;
}
if (*lineptr == NULL || *n == 0)
{
*n = 120;
*lineptr = (char *) malloc(*n);
if (*lineptr == NULL)
{
result = -1;
goto unlock_return;
}
}
len = fp->_IO_read_end - fp->_IO_read_ptr;
if (len <= 0)
{
if (__underflow(fp) == EOF)
{
result = -1;
goto unlock_return;
}
len = fp->_IO_read_end - fp->_IO_read_ptr;
}
for (;;)
{
_IO_size_t needed;
char *t;
t = (char *) memchr((void *) fp->_IO_read_ptr, delimiter, len);
if (t != NULL)
len = (t - fp->_IO_read_ptr) + 1;
if (__glibc_unlikely(len >= SSIZE_MAX - cur_len))
{
__set_errno(EOVERFLOW);
result = -1;
goto unlock_return;
}
/* Make enough space for len+1 (for final NUL) bytes. */
needed = cur_len + len + 1;
if (needed > *n)
{
char *new_lineptr;
if (needed < 2 * *n)
needed = 2 * *n; /* Be generous. */
new_lineptr = (char *) realloc(*lineptr, needed);
if (new_lineptr == NULL)
{
result = -1;
goto unlock_return;
}
*lineptr = new_lineptr;
*n = needed;
}
memcpy(*lineptr + cur_len, (void *) fp->_IO_read_ptr, len);
fp->_IO_read_ptr += len;
cur_len += len;
if (t != NULL || __underflow(fp) == EOF)
break;
len = fp->_IO_read_end - fp->_IO_read_ptr;
}
(*lineptr)[cur_len] = '\0';
result = cur_len;
unlock_return:
_IO_release_lock(fp);
return result;
}
