postlicyd/filter.h

   1 /******************************************************************************/
   2 /*          pfixtools: a collection of postfix related tools                  */
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  30 /******************************************************************************/
  31
  32 /*
  33  * Copyright © 2008 Florent Bruneau
  34  */
  35
  36 #ifndef PFIXTOOLS_FILTER_H
  37 #define PFIXTOOLS_FILTER_H
  38
  39 #include "common.h"
  40 #include "filter_tokens.h"
  41 #include "hook_tokens.h"
  42 #include "param_tokens.h"
  43 #include "query.h"
  44 #include "array.h"
  45
  46
  47 typedef filter_token filter_type_t;
  48 typedef hook_token   filter_result_t;
  49 typedef param_token  filter_param_id_t;
  50
  51 typedef struct filter_hook_t {
  52     filter_result_t type;
  53     char *value;
  54
  55     int counter;
  56     int cost;
  57
  58     unsigned postfix:1;
  59     unsigned async:1;
  60     int filter_id;
  61
  62 } filter_hook_t;
  63 ARRAY(filter_hook_t)
  64
  65 typedef struct filter_param_t {
  66     filter_param_id_t type;
  67     char  *value;
  68     int    value_len;
  69 } filter_param_t;
  70 ARRAY(filter_param_t)
  71
  72 /** Description of a filter.
  73  */
  74 typedef struct filter_t {
  75     char *name;
  76     filter_type_t type;
  77
  78     A(filter_hook_t)   hooks;
  79     void *data;
  80
  81     A(filter_param_t) params;
  82
  83     /* Loop checking flags.
  84      */
  85     int last_seen;
  86 } filter_t;
  87 ARRAY(filter_t)
  88
  89 #define MAX_COUNTERS (64)
  90
  91 /** Context of the query. To be filled with data to use when
  92  * performing asynchronous filtering.
  93  */
  94 typedef struct filter_context_t {
  95     /* filter context
  96      */
  97     const filter_t *current_filter;
  98     void *contexts[FTK_count];
  99
 100     /* message context
 101      */
 102     char instance[64];
 103     uint32_t counters[MAX_COUNTERS];
 104
 105     /* connection context
 106      */
 107     void *data;
 108 } filter_context_t;
 109
 110
 111 #define FILTER_INIT { NULL, FTK_UNKNOWN, ARRAY_INIT, NULL, ARRAY_INIT, -1 }
 112 #define CHECK_FILTER(Filter)                                                   \
 113     assert(Filter != FTK_UNKNOWN && Filter != FTK_count                        \
 114            && "Unknown filter type")
 115 #define CHECK_HOOK(Hook)                                                       \
 116     assert(Hook != HTK_UNKNOWN && Hook != HTK_count                            \
 117            && "Unknown hook")
 118 #define CHECK_PARAM(Param)                                                     \
 119     assert(Param != ATK_UNKNOWN && Param != ATK_count                          \
 120            && "Unknown param")
 121
 122
 123 /* Callback to be implemented by a filter.
 124  */
 125
 126 typedef filter_result_t (*filter_runner_t)(const filter_t *filter,
 127                                            const query_t *query,
 128                                            filter_context_t *context);
 129 typedef bool (*filter_constructor_t)(filter_t *filter);
 130 typedef void (*filter_destructor_t)(filter_t *filter);
 131
 132 typedef void *(*filter_context_constructor_t)(void);
 133 typedef void (*filter_context_destructor_t)(void*);
 134
 135 typedef void (*filter_async_handler_t)(filter_context_t *context,
 136                                        const filter_hook_t *result);
 137
 138 /** Number of filter currently running.
 139  */
 140 extern uint32_t filter_running;
 141
 142 /* Registration.
 143  */
 144
 145 __attribute__((nonnull(1,4)))
 146 filter_type_t filter_register(const char *type, filter_constructor_t constructor,
 147                               filter_destructor_t destructor, filter_runner_t runner,
 148                               filter_context_constructor_t context_constructor,
 149                               filter_context_destructor_t context_destructor);
 150
 151 __attribute__((nonnull(2)))
 152 filter_result_t filter_hook_register(filter_type_t filter, const char *name);
 153
 154 __attribute__((nonnull(2)))
 155 filter_param_id_t filter_param_register(filter_type_t filter, const char *name);
 156
 157 __attribute__((nonnull))
 158 void filter_async_handler_register(filter_async_handler_t handler);
 159
 160 /* Filter builder.
 161  */
 162
 163 __attribute__((nonnull(1)))
 164 static inline void filter_init(filter_t *filter)
 165 {
 166     const filter_t f = FILTER_INIT;
 167     *filter = f;
 168 }
 169
 170 __attribute__((nonnull(1,2)))
 171 void filter_set_name(filter_t *filter, const char *name, int len);
 172
 173 __attribute__((nonnull(1,2)))
 174 bool filter_set_type(filter_t *filter, const char *type, int len);
 175
 176 __attribute__((nonnull(1,2,4)))
 177 bool filter_add_param(filter_t *filter, const char *name, int name_len,
 178                       const char *value, int value_len);
 179
 180 __attribute__((nonnull(1,2,4)))
 181 bool filter_add_hook(filter_t *filter, const char *name, int name_len,
 182                      const char *value, int value_len);
 183
 184 __attribute__((nonnull(1)))
 185 bool filter_build(filter_t *filter);
 186
 187 __attribute__((nonnull(1,2)))
 188 static inline int filter_find_with_name(const A(filter_t) *array, const char *name)
 189 {
 190     int start = 0;
 191     int end   = array->len;
 192
 193     while (start < end) {
 194         int mid = (start + end) / 2;
 195         int cmp = strcmp(name, array_elt(*array, mid).name);
 196
 197         if (cmp == 0) {
 198             return mid;
 199         } else if (cmp < 0) {
 200             end = mid;
 201         } else {
 202             start = mid + 1;
 203         }
 204     }
 205     return -1;
 206 }
 207
 208 __attribute__((nonnull(1,2)))
 209 bool filter_update_references(filter_t *filter, A(filter_t) *array);
 210
 211 __attribute__((nonnull(1)))
 212 bool filter_check_safety(A(filter_t) *array);
 213
 214 __attribute__((nonnull(1)))
 215 static inline void filter_hook_wipe(filter_hook_t *hook)
 216 {
 217     p_delete(&hook->value);
 218 }
 219
 220 __attribute__((nonnull(1)))
 221 static inline void filter_params_wipe(filter_param_t *param)
 222 {
 223     p_delete(&param->value);
 224 }
 225
 226 __attribute__((nonnull(1)))
 227 void filter_wipe(filter_t *filter);
 228
 229
 230 /* Runner.
 231  */
 232
 233 __attribute__((nonnull(1,2)))
 234 const filter_hook_t *filter_run(const filter_t *filter, const query_t *query,
 235                                 filter_context_t *context);
 236
 237 __attribute__((nonnull(1,2)))
 238 bool filter_test(const filter_t *filter, const query_t *query,
 239                  filter_context_t *context, filter_result_t expt);
 240
 241
 242 /* Parsing Helpers
 243  */
 244
 245 #define FILTER_PARAM_PARSE_STRING(Param, Dest)                                 \
 246     case ATK_ ## Param: {                                                      \
 247         (Dest) = param->value;                                                 \
 248     } break
 249
 250 #define FILTER_PARAM_PARSE_INT(Param, Dest)                                    \
 251     case ATK_ ## Param: {                                                      \
 252         char *next;                                                            \
 253         (Dest) = strtol(param->value, &next, 10);                              \
 254         PARSE_CHECK(!*next, "invalid %s value %.*s", atokens[ATK_ ## Param],   \
 255                     param->value_len, param->value);                           \
 256      } break
 257
 258 #define FILTER_PARAM_PARSE_BOOLEAN(Param, Dest)                                \
 259     case ATK_ ## Param: {                                                      \
 260         if (param->value_len == 1 && param->value[0] == '1') {                 \
 261             (Dest) = true;                                                     \
 262         } else if (param->value_len == 1 && param->value[0] == '0') {          \
 263             (Dest) = false;                                                    \
 264         } else if (param->value_len == 4                                       \
 265                    && ascii_tolower(param->value[0]) == 't'                    \
 266                    && ascii_tolower(param->value[1]) == 'r'                    \
 267                    && ascii_tolower(param->value[2]) == 'u'                    \
 268                    && ascii_tolower(param->value[3]) == 'e') {                 \
 269             (Dest) = true;                                                     \
 270         } else if (param->value_len == 5                                       \
 271                    && ascii_tolower(param->value[0]) == 'f'                    \
 272                    && ascii_tolower(param->value[1]) == 'a'                    \
 273                    && ascii_tolower(param->value[2]) == 'l'                    \
 274                    && ascii_tolower(param->value[3]) == 's'                    \
 275                    && ascii_tolower(param->value[4]) == 'e') {                 \
 276             (Dest) = false;                                                    \
 277         } else {                                                               \
 278             PARSE_CHECK(false, "invalid %s value %.*s", atokens[ATK_ ## Param],\
 279                         param->value_len, param->value);                       \
 280         }                                                                      \
 281     } break
 282
 283
 284 /* Filter context
 285  */
 286
 287 __attribute__((nonnull(1)))
 288 void filter_context_prepare(filter_context_t *context, void* qctx);
 289
 290 __attribute__((nonnull))
 291 void filter_context_wipe(filter_context_t *context);
 292
 293 __attribute__((nonnull))
 294 void filter_context_clean(filter_context_t *context);
 295
 296 __attribute__((nonnull))
 297 void filter_post_async_result(filter_context_t *context, filter_result_t result);
 298
 299 #endif