diff options
Diffstat (limited to 'REORG.TODO/elf/dl-tunables.h')
| -rw-r--r-- | REORG.TODO/elf/dl-tunables.h | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/REORG.TODO/elf/dl-tunables.h b/REORG.TODO/elf/dl-tunables.h new file mode 100644 index 0000000000..6c49dcbf47 --- /dev/null +++ b/REORG.TODO/elf/dl-tunables.h @@ -0,0 +1,115 @@ +/* The tunable framework. See the README to know how to use the tunable in + a glibc module. + + Copyright (C) 2016-2017 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 + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#ifndef _TUNABLES_H_ +#define _TUNABLES_H_ + +#if !HAVE_TUNABLES +static inline void +__always_inline +__tunables_init (char **unused __attribute__ ((unused))) +{ + /* This is optimized out if tunables are not enabled. */ +} +#else + +# include <stddef.h> +# include "dl-tunable-types.h" + +/* A tunable. */ +struct _tunable +{ + const char *name; /* Internal name of the tunable. */ + tunable_type_t type; /* Data type of the tunable. */ + tunable_val_t val; /* The value. */ + bool initialized; /* Flag to indicate that the tunable is + initialized. */ + tunable_seclevel_t security_level; /* Specify the security level for the + tunable with respect to AT_SECURE + programs. See description of + tunable_seclevel_t to see a + description of the values. + + Note that even if the tunable is + read, it may not get used by the + target module if the value is + considered unsafe. */ + /* Compatibility elements. */ + const char *env_alias; /* The compatibility environment + variable name. */ +}; + +typedef struct _tunable tunable_t; + +/* Full name for a tunable is top_ns.tunable_ns.id. */ +# define TUNABLE_NAME_S(top,ns,id) #top "." #ns "." #id + +# define TUNABLE_ENUM_NAME(__top,__ns,__id) TUNABLE_ENUM_NAME1 (__top,__ns,__id) +# define TUNABLE_ENUM_NAME1(__top,__ns,__id) __top ## _ ## __ns ## _ ## __id + +# include "dl-tunable-list.h" + +extern void __tunables_init (char **); +extern void __tunable_get_val (tunable_id_t, void *, tunable_callback_t); +extern void __tunable_set_val (tunable_id_t, void *); +rtld_hidden_proto (__tunables_init) +rtld_hidden_proto (__tunable_get_val) + +/* Define TUNABLE_GET and TUNABLE_SET in short form if TOP_NAMESPACE and + TUNABLE_NAMESPACE are defined. This is useful shorthand to get and set + tunables within a module. */ +#if defined TOP_NAMESPACE && defined TUNABLE_NAMESPACE +# define TUNABLE_GET(__id, __type, __cb) \ + TUNABLE_GET_FULL (TOP_NAMESPACE, TUNABLE_NAMESPACE, __id, __type, __cb) +# define TUNABLE_SET(__id, __type, __val) \ + TUNABLE_SET_FULL (TOP_NAMESPACE, TUNABLE_NAMESPACE, __id, __type, __val) +#else +# define TUNABLE_GET(__top, __ns, __id, __type, __cb) \ + TUNABLE_GET_FULL (__top, __ns, __id, __type, __cb) +# define TUNABLE_SET(__top, __ns, __id, __type, __val) \ + TUNABLE_SET_FULL (__top, __ns, __id, __type, __val) +#endif + +/* Get and return a tunable value. If the tunable was set externally and __CB + is defined then call __CB before returning the value. */ +# define TUNABLE_GET_FULL(__top, __ns, __id, __type, __cb) \ +({ \ + tunable_id_t id = TUNABLE_ENUM_NAME (__top, __ns, __id); \ + __type ret; \ + __tunable_get_val (id, &ret, __cb); \ + ret; \ +}) + +/* Set a tunable value. */ +# define TUNABLE_SET_FULL(__top, __ns, __id, __type, __val) \ +({ \ + __tunable_set_val (TUNABLE_ENUM_NAME (__top, __ns, __id), \ + & (__type) {__val}); \ +}) + +/* Namespace sanity for callback functions. Use this macro to keep the + namespace of the modules clean. */ +# define TUNABLE_CALLBACK(__name) _dl_tunable_ ## __name + +# define TUNABLES_FRONTEND_valstring 1 +/* The default value for TUNABLES_FRONTEND. */ +# define TUNABLES_FRONTEND_yes TUNABLES_FRONTEND_valstring +#endif +#endif |