OpenE2K
/
glibc
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

(_IO_vasprintf): Try to avoid memory fragmentation by allocating new memory at the end instead of reallocating.

This commit is contained in:
Ulrich Drepper 2000-04-11 17:53:41 +00:00
parent 4a1a3c2158
commit 4100c5a0e6
1 changed files with 21 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

25
libio/vasprintf.c
View File

@ -1,4 +1,4 @@
/* Copyright (C) 1995, 1997, 1999 Free Software Foundation, Inc. /* Copyright (C) 1995, 1997, 1999, 2000 Free Software Foundation, Inc.
This file is part of the GNU IO Library. This file is part of the GNU IO Library.
This library is free software; you can redistribute it and/or This library is free software; you can redistribute it and/or
@ -43,6 +43,8 @@ _IO_vasprintf (result_ptr, format, args)
_IO_lock_t lock; _IO_lock_t lock;
#endif #endif
int ret; int ret;
_IO_size_t needed;
_IO_size_t allocated;
string = (char *) malloc (init_string_size); string = (char *) malloc (init_string_size);
if (string == NULL) if (string == NULL)
return -1; return -1;
@ -58,9 +60,24 @@ _IO_vasprintf (result_ptr, format, args)
ret = _IO_vfprintf ((_IO_FILE *) &sf, format, args); ret = _IO_vfprintf ((_IO_FILE *) &sf, format, args);
if (ret < 0) if (ret < 0)
return ret; return ret;
*result_ptr = (char *) realloc (sf._sbf._f._IO_buf_base, /* Only use realloc if the size we need is of the same order of
(sf._sbf._f._IO_write_ptr magnitude then the memory we allocated. */
- sf._sbf._f._IO_write_base) +1); needed = sf._sbf._f._IO_write_ptr - sf._sbf._f._IO_write_base + 1;
allocated = sf._sbf._f._IO_write_end - sf._sbf._f._IO_write_base;
if ((allocated << 1) <= needed)
*result_ptr = (char *) realloc (sf._sbf._f._IO_buf_base, needed);
else
{
*result_ptr = (char *) malloc (needed);
if (*result_ptr != NULL)
{
memcpy (*result_ptr, sf._sbf._f._IO_buf_base, needed);
free (sf._sbf._f._IO_buf_base);
}
else
/* We have no choice, use the buffer we already have. */
*result_ptr = (char *) realloc (sf._sbf._f._IO_buf_base, needed);
}
if (*result_ptr == NULL) if (*result_ptr == NULL)
*result_ptr = sf._sbf._f._IO_buf_base; *result_ptr = sf._sbf._f._IO_buf_base;
(*result_ptr)[sf._sbf._f._IO_write_ptr-sf._sbf._f._IO_write_base] = '\0'; (*result_ptr)[sf._sbf._f._IO_write_ptr-sf._sbf._f._IO_write_base] = '\0';