diff options
Diffstat (limited to 'resolv/res_libc.c')
-rw-r--r-- | resolv/res_libc.c | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/resolv/res_libc.c b/resolv/res_libc.c new file mode 100644 index 0000000000..14d565df0d --- /dev/null +++ b/resolv/res_libc.c @@ -0,0 +1,98 @@ +/* + * Copyright (c) 1995-1999 by Internet Software Consortium. + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS + * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE + * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL + * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR + * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS + * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS + * SOFTWARE. + */ + +/* Define some functions that go int libc.so. */ + +#if defined(LIBC_SCCS) && !defined(lint) +static const char rcsid[] = "$Id$"; +#endif /* LIBC_SCCS and not lint */ + +#include <sys/types.h> +#include <sys/param.h> +#include <sys/socket.h> +#include <sys/time.h> + +#include <netinet/in.h> +#include <arpa/inet.h> +#include <arpa/nameser.h> + +#include <ctype.h> +#include <netdb.h> +#include <resolv.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#undef _res + +struct __res_state _res; + +/* This is the old res_init function. It has been moved from + res_data.c to this file since res_init should go into libc.so but + the rest of res_data not. */ + + +int +res_init(void) { + extern int __res_vinit(res_state, int); + + /* + * These three fields used to be statically initialized. This made + * it hard to use this code in a shared library. It is necessary, + * now that we're doing dynamic initialization here, that we preserve + * the old semantics: if an application modifies one of these three + * fields of _res before res_init() is called, res_init() will not + * alter them. Of course, if an application is setting them to + * _zero_ before calling res_init(), hoping to override what used + * to be the static default, we can't detect it and unexpected results + * will follow. Zero for any of these fields would make no sense, + * so one can safely assume that the applications were already getting + * unexpected results. + * + * _res.options is tricky since some apps were known to diddle the bits + * before res_init() was first called. We can't replicate that semantic + * with dynamic initialization (they may have turned bits off that are + * set in RES_DEFAULT). Our solution is to declare such applications + * "broken". They could fool us by setting RES_INIT but none do (yet). + */ + if (!_res.retrans) + _res.retrans = RES_TIMEOUT; + if (!_res.retry) + _res.retry = 4; + if (!(_res.options & RES_INIT)) + _res.options = RES_DEFAULT; + + /* + * This one used to initialize implicitly to zero, so unless the app + * has set it to something in particular, we can randomize it now. + */ + if (!_res.id) + _res.id = res_randomid(); + + return (__res_vinit(&_res, 1)); +} + +/* We need a resolver context - in unthreaded apps, this weak function + provides it. */ + +struct __res_state * +weak_const_function +__res_state(void) +{ + return &_res; +} |