1berry/ruby
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

io.c: IO#pwrite uses tmp buffer to avoid parallel modification

Browse Source 
Since we release GVL, we must freeze and duplicate the string buffer
to prevent other threads from modifying our buffer while we are
waiting on pwrite(2).

* io.c (rb_io_pwrite): use_rb_str_tmp_frozen_{acquire/release}
  [Bug #14195]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61376 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
This commit is contained in:
normal 2017-12-21 00:26:24 +00:00
parent b895c402a5
commit 3b174fb7d6
1 changed files with 6 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
io.c
View File

@ -5186,12 +5186,11 @@ rb_io_pwrite(VALUE io, VALUE str, VALUE offset)
rb_io_t *fptr;
ssize_t n;
struct prdwr_internal_arg arg;
VALUE tmp;
if (!RB_TYPE_P(str, T_STRING))
str = rb_obj_as_string(str);
arg.buf = RSTRING_PTR(str);
arg.count = (size_t)RSTRING_LEN(str);
arg.offset = NUM2OFFT(offset);
io = GetWriteIO(io);
@ -5199,10 +5198,13 @@ rb_io_pwrite(VALUE io, VALUE str, VALUE offset)
rb_io_check_writable(fptr);
arg.fd = fptr->fd;
n = (ssize_t)rb_thread_io_blocking_region(internal_pwrite_func, &arg, fptr->fd);
RB_GC_GUARD(str);
tmp = rb_str_tmp_frozen_acquire(str);
arg.buf = RSTRING_PTR(tmp);
arg.count = (size_t)RSTRING_LEN(tmp);
n = (ssize_t)rb_thread_io_blocking_region(internal_pwrite_func, &arg, fptr->fd);
if (n == -1) rb_sys_fail_path(fptr->pathv);
rb_str_tmp_frozen_release(str, tmp);
return SSIZET2NUM(n);
}