conf/conf.c

   1 /*
   2  *      BIRD Internet Routing Daemon -- Configuration File Handling
   3  *
   4  *      (c) 1998--2000 Martin Mares <mj@ucw.cz>
   5  *
   6  *      Can be freely distributed and used under the terms of the GNU GPL.
   7  */
   8
   9 #include <setjmp.h>
  10 #include <stdarg.h>
  11
  12 #define LOCAL_DEBUG
  13
  14 #include "nest/bird.h"
  15 #include "nest/route.h"
  16 #include "nest/protocol.h"
  17 #include "nest/iface.h"
  18 #include "lib/resource.h"
  19 #include "lib/string.h"
  20 #include "lib/event.h"
  21 #include "conf/conf.h"
  22 #include "filter/filter.h"
  23
  24 static jmp_buf conf_jmpbuf;
  25
  26 struct config *config, *new_config, *old_config, *future_config;
  27 static event *config_event;
  28 int shutting_down;
  29
  30 struct config *
  31 config_alloc(byte *name)
  32 {
  33   pool *p = rp_new(&root_pool, "Config");
  34   linpool *l = lp_new(p, 4080);
  35   struct config *c = lp_allocz(l, sizeof(struct config));
  36
  37   c->pool = p;
  38   cfg_mem = c->mem = l;
  39   c->file_name = cfg_strdup(name);
  40   return c;
  41 }
  42
  43 int
  44 config_parse(struct config *c)
  45 {
  46   debug("Parsing configuration file `%s'\n", c->file_name);
  47   new_config = c;
  48   cfg_mem = c->mem;
  49   if (setjmp(conf_jmpbuf))
  50     return 0;
  51   cf_lex_init(0);
  52   sysdep_preconfig(c);
  53   protos_preconfig(c);
  54   rt_preconfig(c);
  55   cf_parse();
  56   filters_postconfig();                 /* FIXME: Do we really need this? */
  57   protos_postconfig(c);
  58 #ifdef IPV6
  59   if (!c->router_id)
  60     cf_error("Router ID must be configured manually on IPv6 routers");
  61 #endif
  62   return 1;
  63 }
  64
  65 int
  66 cli_parse(struct config *c)
  67 {
  68   new_config = c;
  69   c->sym_fallback = config->sym_hash;
  70   cfg_mem = c->mem;
  71   if (setjmp(conf_jmpbuf))
  72     return 0;
  73   cf_lex_init(1);
  74   cf_parse();
  75   return 1;
  76 }
  77
  78 void
  79 config_free(struct config *c)
  80 {
  81   rfree(c->pool);
  82 }
  83
  84 void
  85 config_add_obstacle(struct config *c)
  86 {
  87   DBG("+++ adding obstacle %d\n", c->obstacle_count);
  88   c->obstacle_count++;
  89 }
  90
  91 void
  92 config_del_obstacle(struct config *c)
  93 {
  94   DBG("+++ deleting obstacle %d\n", c->obstacle_count);
  95   c->obstacle_count--;
  96   if (!c->obstacle_count)
  97     {
  98       ASSERT(config_event);
  99       ev_schedule(config_event);
 100     }
 101 }
 102
 103 static int
 104 global_commit(struct config *new, struct config *old)
 105 {
 106   if (!old)
 107     return 0;
 108   if (!new->router_id)
 109     new->router_id = old->router_id;
 110   if (new->router_id != old->router_id)
 111     return 1;
 112   return 0;
 113 }
 114
 115 static int
 116 config_do_commit(struct config *c)
 117 {
 118   int force_restart, nobs;
 119
 120   DBG("do_commit\n");
 121   old_config = config;
 122   config = new_config = c;
 123   if (old_config)
 124     old_config->obstacle_count++;
 125   DBG("sysdep_commit\n");
 126   force_restart = sysdep_commit(c, old_config);
 127   DBG("global_commit\n");
 128   force_restart |= global_commit(c, old_config);
 129   DBG("rt_commit\n");
 130   rt_commit(c, old_config);
 131   DBG("protos_commit\n");
 132   protos_commit(c, old_config, force_restart);
 133   new_config = NULL;                    /* Just to be sure nobody uses that now */
 134   if (old_config)
 135     nobs = --old_config->obstacle_count;
 136   else
 137     nobs = 0;
 138   DBG("do_commit finished with %d obstacles remaining\n", nobs);
 139   return !nobs;
 140 }
 141
 142 static int
 143 config_done(void *unused)
 144 {
 145   struct config *c;
 146
 147   DBG("config_done\n");
 148   for(;;)
 149     {
 150       if (config->shutdown)
 151         sysdep_shutdown_done();
 152       log(L_INFO "Reconfigured");
 153       if (old_config)
 154         {
 155           config_free(old_config);
 156           old_config = NULL;
 157         }
 158       if (!future_config)
 159         break;
 160       c = future_config;
 161       future_config = NULL;
 162       log(L_INFO "Switching to queued configuration...");
 163       if (!config_do_commit(c))
 164         break;
 165     }
 166   return 0;
 167 }
 168
 169 int
 170 config_commit(struct config *c)
 171 {
 172   if (!config)                          /* First-time configuration */
 173     {
 174       config_do_commit(c);
 175       return CONF_DONE;
 176     }
 177   if (old_config)                       /* Reconfiguration already in progress */
 178     {
 179       if (shutting_down)
 180         {
 181           log(L_INFO "New configuration discarded due to shutdown");
 182           config_free(c);
 183           return CONF_SHUTDOWN;
 184         }
 185       if (future_config)
 186         {
 187           log(L_INFO "Queueing new configuration, ignoring the one already queued");
 188           config_free(future_config);
 189         }
 190       else
 191         log(L_INFO "Queued new configuration");
 192       future_config = c;
 193       return CONF_QUEUED;
 194     }
 195   if (config_do_commit(c))
 196     {
 197       config_done(NULL);
 198       return CONF_DONE;
 199     }
 200   if (!config_event)
 201     {
 202       config_event = ev_new(&root_pool);
 203       config_event->hook = config_done;
 204     }
 205   return CONF_PROGRESS;
 206 }
 207
 208 void
 209 order_shutdown(void)
 210 {
 211   struct config *c;
 212
 213   if (shutting_down)
 214     return;
 215   log(L_INFO "Shutting down");
 216   c = lp_alloc(config->mem, sizeof(struct config));
 217   memcpy(c, config, sizeof(struct config));
 218   init_list(&c->protos);
 219   init_list(&c->tables);
 220   c->shutdown = 1;
 221   config_commit(c);
 222   shutting_down = 1;
 223 }
 224
 225 void
 226 cf_error(char *msg, ...)
 227 {
 228   char buf[1024];
 229   va_list args;
 230
 231   va_start(args, msg);
 232   if (bvsnprintf(buf, sizeof(buf), msg, args) < 0)
 233     strcpy(buf, "<bug: error message too long>");
 234   new_config->err_msg = cfg_strdup(buf);
 235   new_config->err_lino = conf_lino;
 236   longjmp(conf_jmpbuf, 1);
 237 }
 238
 239 char *
 240 cfg_strdup(char *c)
 241 {
 242   int l = strlen(c) + 1;
 243   char *z = cfg_allocu(l);
 244   memcpy(z, c, l);
 245   return z;
 246 }