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-rw-r--r--libio/strops.c125
1 files changed, 83 insertions, 42 deletions
diff --git a/libio/strops.c b/libio/strops.c
index 2de83403a2..05270ce407 100644
--- a/libio/strops.c
+++ b/libio/strops.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1993, 1997-2003, 2004 Free Software Foundation, Inc.
+/* Copyright (C) 1993, 1997-2003, 2004, 2006 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
@@ -25,43 +25,12 @@
This exception applies to code released by its copyright holders
in files containing the exception. */
+#include <assert.h>
#include "strfile.h"
#include "libioP.h"
#include <string.h>
#include <stdio_ext.h>
-#if 0
-/* The following definitions are for exposition only.
- They map the terminology used in the ANSI/ISO C++ draft standard
- to the implementation. */
-
-/* allocated: set when a dynamic array object has been allocated, and
- hence should be freed by the destructor for the strstreambuf object. */
-#define ALLOCATED(FP) ((FP)->_f._IO_buf_base && DYNAMIC(FP))
-
-/* constant: set when the array object has const elements,
- so the output sequence cannot be written. */
-#define CONSTANT(FP) ((FP)->_f._IO_file_flags & _IO_NO_WRITES)
-
-/* alsize: the suggested minimum size for a dynamic array object. */
-#define ALSIZE(FP) ??? /* not stored */
-
-/* palloc: points to the function to call to allocate a dynamic array object.*/
-#define PALLOC(FP) \
- ((FP)->_s._allocate_buffer == default_alloc ? 0 : (FP)->_s._allocate_buffer)
-
-/* pfree: points to the function to call to free a dynamic array object. */
-#define PFREE(FP) \
- ((FP)->_s._free_buffer == default_free ? 0 : (FP)->_s._free_buffer)
-
-#endif
-
-#ifdef TODO
-/* An "unbounded buffer" is when a buffer is supplied, but with no
- specified length. An example is the buffer argument to sprintf.
- */
-#endif
-
void
_IO_str_init_static_internal (sf, ptr, size, pstart)
_IO_strfile *sf;
@@ -134,7 +103,7 @@ _IO_str_overflow (fp, c)
fp->_IO_write_ptr = fp->_IO_read_ptr;
fp->_IO_read_ptr = fp->_IO_read_end;
}
- pos = fp->_IO_write_ptr - fp->_IO_write_base;
+ pos = fp->_IO_write_ptr - fp->_IO_write_base;
if (pos >= (_IO_size_t) (_IO_blen (fp) + flush_only))
{
if (fp->_flags & _IO_USER_BUF) /* not allowed to enlarge */
@@ -143,7 +112,10 @@ _IO_str_overflow (fp, c)
{
char *new_buf;
char *old_buf = fp->_IO_buf_base;
- _IO_size_t new_size = 2 * _IO_blen (fp) + 100;
+ size_t old_blen = _IO_blen (fp);
+ _IO_size_t new_size = 2 * old_blen + 100;
+ if (new_size < old_blen)
+ return EOF;
new_buf
= (char *) (*((_IO_strfile *) fp)->_s._allocate_buffer) (new_size);
if (new_buf == NULL)
@@ -153,15 +125,13 @@ _IO_str_overflow (fp, c)
}
if (old_buf)
{
- memcpy (new_buf, old_buf, _IO_blen (fp));
+ memcpy (new_buf, old_buf, old_blen);
(*((_IO_strfile *) fp)->_s._free_buffer) (old_buf);
/* Make sure _IO_setb won't try to delete _IO_buf_base. */
fp->_IO_buf_base = NULL;
}
-#if 0
- if (lenp == &LEN(fp)) /* use '\0'-filling */
- memset (new_buf + pos, 0, blen() - pos);
-#endif
+ memset (new_buf + old_blen, '\0', new_size - old_blen);
+
INTUSE(_IO_setb) (fp, new_buf, new_buf + new_size, 1);
fp->_IO_read_base = new_buf + (fp->_IO_read_base - old_buf);
fp->_IO_read_ptr = new_buf + (fp->_IO_read_ptr - old_buf);
@@ -211,6 +181,71 @@ _IO_str_count (fp)
- fp->_IO_read_base);
}
+
+static int
+enlarge_userbuf (_IO_FILE *fp, _IO_off64_t offset, int reading)
+{
+ if ((_IO_ssize_t) offset <= _IO_blen (fp))
+ return 0;
+
+ _IO_ssize_t oldend = fp->_IO_write_end - fp->_IO_write_base;
+
+ /* Try to enlarge the buffer. */
+ if (fp->_flags & _IO_USER_BUF)
+ /* User-provided buffer. */
+ return 1;
+
+ _IO_size_t newsize = offset + 100;
+ char *oldbuf = fp->_IO_buf_base;
+ char *newbuf
+ = (char *) (*((_IO_strfile *) fp)->_s._allocate_buffer) (newsize);
+ if (newbuf == NULL)
+ return 1;
+
+ if (oldbuf != NULL)
+ {
+ memcpy (newbuf, oldbuf, _IO_blen (fp));
+ (*((_IO_strfile *) fp)->_s._free_buffer) (oldbuf);
+ /* Make sure _IO_setb won't try to delete
+ _IO_buf_base. */
+ fp->_IO_buf_base = NULL;
+ }
+
+ INTUSE(_IO_setb) (fp, newbuf, newbuf + newsize, 1);
+
+ if (reading)
+ {
+ fp->_IO_write_base = newbuf + (fp->_IO_write_base - oldbuf);
+ fp->_IO_write_ptr = newbuf + (fp->_IO_write_ptr - oldbuf);
+ fp->_IO_write_end = newbuf + (fp->_IO_write_end - oldbuf);
+ fp->_IO_read_ptr = newbuf + (fp->_IO_read_ptr - oldbuf);
+
+ fp->_IO_read_base = newbuf;
+ fp->_IO_read_end = fp->_IO_buf_end;
+ }
+ else
+ {
+ fp->_IO_read_base = newbuf + (fp->_IO_read_base - oldbuf);
+ fp->_IO_read_ptr = newbuf + (fp->_IO_read_ptr - oldbuf);
+ fp->_IO_read_end = newbuf + (fp->_IO_read_end - oldbuf);
+ fp->_IO_write_ptr = newbuf + (fp->_IO_write_ptr - oldbuf);
+
+ fp->_IO_write_base = newbuf;
+ fp->_IO_write_end = fp->_IO_buf_end;
+ }
+
+ /* Clear the area between the last write position and th
+ new position. */
+ assert (offset >= oldend);
+ if (reading)
+ memset (fp->_IO_read_base + oldend, '\0', offset - oldend);
+ else
+ memset (fp->_IO_write_base + oldend, '\0', offset - oldend);
+
+ return 0;
+}
+
+
_IO_off64_t
_IO_str_seekoff (fp, offset, dir, mode)
_IO_FILE *fp;
@@ -251,7 +286,10 @@ _IO_str_seekoff (fp, offset, dir, mode)
default: /* case _IO_seek_set: */
break;
}
- if (offset < 0 || (_IO_ssize_t) offset > cur_size)
+ if (offset < 0)
+ return EOF;
+ if ((_IO_ssize_t) offset > cur_size
+ && enlarge_userbuf (fp, offset, 1) != 0)
return EOF;
fp->_IO_read_ptr = fp->_IO_read_base + offset;
fp->_IO_read_end = fp->_IO_read_base + cur_size;
@@ -272,7 +310,10 @@ _IO_str_seekoff (fp, offset, dir, mode)
default: /* case _IO_seek_set: */
break;
}
- if (offset < 0 || (_IO_ssize_t) offset > cur_size)
+ if (offset < 0)
+ return EOF;
+ if ((_IO_ssize_t) offset > cur_size
+ && enlarge_userbuf (fp, offset, 0) != 0)
return EOF;
fp->_IO_write_ptr = fp->_IO_write_base + offset;
new_pos = offset;