postlicyd/counters.c

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  30 /******************************************************************************/
  31
  32 /*
  33  * Copyright © 2008 Florent Bruneau
  34  */
  35
  36 #include "filter.h"
  37 #include "config.h"
  38 #include "query.h"
  39
  40 typedef struct counter_config_t {
  41     int counter;
  42     uint32_t hard_threshold;
  43     uint32_t soft_threshold;
  44 } counter_config_t;
  45
  46
  47 static counter_config_t *counter_config_new(void)
  48 {
  49     return p_new(counter_config_t, 1);
  50 }
  51
  52 static void counter_config_delete(counter_config_t **config)
  53 {
  54     if (*config) {
  55         p_delete(config);
  56     }
  57 }
  58
  59 static bool counter_filter_constructor(filter_t *filter)
  60 {
  61     counter_config_t *config = counter_config_new();
  62     config->counter = -1;
  63
  64 #define PARSE_CHECK(Expr, Str, ...)                                            \
  65     if (!(Expr)) {                                                             \
  66         err(Str, ##__VA_ARGS__);                                               \
  67         counter_config_delete(&config);                                          \
  68         return false;                                                          \
  69     }
  70
  71     foreach (filter_param_t *param, filter->params) {
  72         switch (param->type) {
  73           FILTER_PARAM_PARSE_INT(COUNTER, config->counter);
  74           FILTER_PARAM_PARSE_INT(HARD_THRESHOLD, config->hard_threshold);
  75           FILTER_PARAM_PARSE_INT(SOFT_THRESHOLD, config->soft_threshold);
  76           default: break;
  77         }
  78     }}
  79
  80     PARSE_CHECK(config->counter >= 0 && config->counter < MAX_COUNTERS,
  81                 "invalid counter number: %d", config->counter);
  82     filter->data = config;
  83     return true;
  84 }
  85
  86 static void counter_filter_destructor(filter_t *filter)
  87 {
  88     counter_config_t *config = filter->data;
  89     counter_config_delete(&config);
  90     filter->data = config;
  91 }
  92
  93 static filter_result_t counter_filter(const filter_t *filter, const query_t *query,
  94                                       filter_context_t *context)
  95 {
  96     const counter_config_t *counter = filter->data;
  97     const uint32_t val = context->counters[counter->counter];
  98
  99     if (val >= counter->hard_threshold) {
 100         return HTK_HARD_MATCH;
 101     } else if (val >= counter->soft_threshold) {
 102         return HTK_SOFT_MATCH;
 103     } else {
 104         return HTK_FAIL;
 105     }
 106 }
 107
 108 static int counter_init(void)
 109 {
 110     filter_type_t type =  filter_register("counter", counter_filter_constructor,
 111                                           counter_filter_destructor, counter_filter,
 112                                           NULL, NULL);
 113     /* Hooks.
 114      */
 115     (void)filter_hook_register(type, "fail");
 116     (void)filter_hook_register(type, "hard_match");
 117     (void)filter_hook_register(type, "soft_match");
 118
 119     /* Parameters.
 120      */
 121     (void)filter_param_register(type, "counter");
 122     (void)filter_param_register(type, "hard_threshold");
 123     (void)filter_param_register(type, "soft_threshold");
 124     return 0;
 125 }
 126 module_init(counter_init);