lib/defaults.h

   1 /*
   2  * FRR switchable defaults.
   3  * Copyright (C) 2017-2019  David Lamparter for NetDEF, Inc.
   4  *
   5  * Permission to use, copy, modify, and distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 #ifndef _FRR_DEFAULTS_H
  19 #define _FRR_DEFAULTS_H
  20
  21 #include "config.h"
  22
  23 #include <stdbool.h>
  24
  25 #include "compiler.h"
  26
  27 #ifdef HAVE_DATACENTER
  28
  29 #define DFLT_OSPF_LOG_ADJACENCY_CHANGES         1
  30 #define DFLT_OSPF6_LOG_ADJACENCY_CHANGES        1
  31
  32 #else  /* !HAVE_DATACENTER */
  33
  34 #define DFLT_OSPF_LOG_ADJACENCY_CHANGES         0
  35 #define DFLT_OSPF6_LOG_ADJACENCY_CHANGES        0
  36
  37 #endif /* !HAVE_DATACENTER */
  38
  39 /* frr_default wraps information about a default that has different
  40  * values depending on FRR version or default-set
  41  *
  42  * frr_default_entry describes one match rule and the resulting value;
  43  * entries are evaluated in order and the first matching is used.
  44  *
  45  * If both match_version and match_profile are specified, they must both
  46  * match.  A NULL value matches everything.
  47  */
  48 struct frr_default_entry {
  49         /* syntax: "(<|<=|==|>=|>) [whitespace] version", e.g.
  50          *   ">= 6.1-dev" "<6.0"
  51          */
  52         const char *match_version;
  53         /* exact profile string to compare against */
  54         const char *match_profile;
  55
  56         /* value to use */
  57         bool val_bool;
  58         const char *val_str;
  59         long val_long;
  60         unsigned long val_ulong;
  61         float val_float;
  62 };
  63
  64 /* one struct frr_default exists for each malleable default value */
  65 struct frr_default {
  66         struct frr_default *next;
  67
  68         /* for UI/debug use */
  69         const char *name;
  70
  71         /* the following two sets of variables differ because the written
  72          * config always targets the *current* FRR version
  73          *
  74          * e.g. if you load a config that has "frr version 5.0" on 6.0
  75          *   *dflt_long => set to the default value in 5.0
  76          *   *save_long => set to the default value in 6.0
  77          * config save will write "frr version 6.0" with 6.0 defaults
  78          */
  79
  80         /* variable holding the default value for reading/use */
  81         bool *dflt_bool;
  82         const char **dflt_str;
  83         long *dflt_long;
  84         unsigned long *dflt_ulong;
  85         float *dflt_float;
  86
  87         /* variable to use when comparing for config save */
  88         bool *save_bool;
  89         const char **save_str;
  90         long *save_long;
  91         unsigned long *save_ulong;
  92         float *save_float;
  93
  94         struct frr_default_entry entries[];
  95 };
  96
  97 #define _FRR_CFG_DEFAULT(type, typname, varname, ...) \
  98         static type DFLT_##varname;                                            \
  99         static type SAVE_##varname;                                            \
 100         static struct frr_default _dflt_##varname = {                          \
 101                 .name = #varname,                                              \
 102                 .dflt_##typname = &DFLT_##varname,                             \
 103                 .save_##typname = &SAVE_##varname,                             \
 104                 .entries = { __VA_ARGS__ },                                    \
 105         };                                                                     \
 106         static void _dfltinit_##varname(void)                                  \
 107                 __attribute__((_CONSTRUCTOR(1000)));                           \
 108         static void _dfltinit_##varname(void)                                  \
 109         {                                                                      \
 110                 frr_default_add(&_dflt_##varname);                             \
 111         }
 112
 113 /* use:
 114  *   FRR_CFG_DEFAULT_LONG(SHARP_BLUNTNESS,
 115  *      { .val_long = 2, .match_version = ">= 10.0" },
 116  *      { .val_long = 1, .match_profile = "datacenter" },
 117  *      { .val_long = 0 },
 118  *   )
 119  *
 120  * This will create DFLT_SHARP_BLUNTNESS and SAVE_SHARP_BLUNTNESS variables.
 121  *
 122  * Note: preprocessor defines cannot be used as variable names because they
 123  * will be expanded and blow up with a compile error.  Use an enum or add an
 124  * extra _ at the beginning (e.g. _SHARP_BLUNTNESS => DFLT__SHARP_BLUNTNESS)
 125  */
 126 #define FRR_CFG_DEFAULT_BOOL(varname, ...) \
 127         _FRR_CFG_DEFAULT(bool, bool, varname, ## __VA_ARGS__)
 128 #define FRR_CFG_DEFAULT_LONG(varname, ...) \
 129         _FRR_CFG_DEFAULT(long, long, varname, ## __VA_ARGS__)
 130 #define FRR_CFG_DEFAULT_ULONG(varname, ...) \
 131         _FRR_CFG_DEFAULT(unsigned long, ulong, varname, ## __VA_ARGS__)
 132 #define FRR_CFG_DEFAULT_FLOAT(varname, ...) \
 133         _FRR_CFG_DEFAULT(float, float, varname, ## __VA_ARGS__)
 134 #define FRR_CFG_DEFAULT_STR(varname, ...) \
 135         _FRR_CFG_DEFAULT(const char *, str, varname, ## __VA_ARGS__)
 136
 137
 138 /* daemons don't need to call any of these, libfrr handles that */
 139 extern void frr_default_add(struct frr_default *dflt);
 140 extern void frr_defaults_version_set(const char *version);
 141 extern void frr_defaults_profile_set(const char *profile);
 142 extern const char *frr_defaults_version(void);
 143 extern const char *frr_defaults_profile(void);
 144 extern void frr_defaults_apply(void);
 145
 146 extern const char *frr_defaults_profiles[];
 147 extern bool frr_defaults_profile_valid(const char *profile);
 148
 149 /* like strcmp(), but with version ordering */
 150 extern int frr_version_cmp(const char *aa, const char *bb);
 151
 152 #endif /* _FRR_DEFAULTS_H */