postlicyd/counters.c

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  33 /******************************************************************************/
  34
  35 /*
  36  * Copyright © 2008 Florent Bruneau
  37  */
  38
  39 #include "filter.h"
  40 #include "config.h"
  41 #include "query.h"
  42
  43 typedef struct counter_config_t {
  44     int counter;
  45     uint32_t hard_threshold;
  46     uint32_t soft_threshold;
  47 } counter_config_t;
  48
  49
  50 static counter_config_t *counter_config_new(void)
  51 {
  52     return p_new(counter_config_t, 1);
  53 }
  54
  55 static void counter_config_delete(counter_config_t **config)
  56 {
  57     if (*config) {
  58         p_delete(config);
  59     }
  60 }
  61
  62 static bool counter_filter_constructor(filter_t *filter)
  63 {
  64     counter_config_t *config = counter_config_new();
  65     config->counter = -1;
  66
  67 #define PARSE_CHECK(Expr, Str, ...)                                            \
  68     if (!(Expr)) {                                                             \
  69         err(Str, ##__VA_ARGS__);                                               \
  70         counter_config_delete(&config);                                          \
  71         return false;                                                          \
  72     }
  73
  74     config->hard_threshold = 1;
  75     config->soft_threshold = 1;
  76     foreach (filter_param_t *param, filter->params) {
  77         switch (param->type) {
  78           FILTER_PARAM_PARSE_INT(COUNTER, config->counter);
  79           FILTER_PARAM_PARSE_INT(HARD_THRESHOLD, config->hard_threshold);
  80           FILTER_PARAM_PARSE_INT(SOFT_THRESHOLD, config->soft_threshold);
  81           default: break;
  82         }
  83     }}
  84
  85     PARSE_CHECK(config->counter >= 0 && config->counter < MAX_COUNTERS,
  86                 "invalid counter number: %d", config->counter);
  87     filter->data = config;
  88     return true;
  89 }
  90
  91 static void counter_filter_destructor(filter_t *filter)
  92 {
  93     counter_config_t *config = filter->data;
  94     counter_config_delete(&config);
  95     filter->data = config;
  96 }
  97
  98 static filter_result_t counter_filter(const filter_t *filter, const query_t *query,
  99                                       filter_context_t *context)
 100 {
 101     const counter_config_t *counter = filter->data;
 102     const uint32_t val = context->counters[counter->counter];
 103
 104     if (val >= counter->hard_threshold) {
 105         return HTK_HARD_MATCH;
 106     } else if (val >= counter->soft_threshold) {
 107         return HTK_SOFT_MATCH;
 108     } else {
 109         return HTK_FAIL;
 110     }
 111 }
 112
 113 static int counter_init(void)
 114 {
 115     filter_type_t type =  filter_register("counter", counter_filter_constructor,
 116                                           counter_filter_destructor, counter_filter,
 117                                           NULL, NULL);
 118     /* Hooks.
 119      */
 120     (void)filter_hook_register(type, "fail");
 121     (void)filter_hook_register(type, "hard_match");
 122     (void)filter_hook_register(type, "soft_match");
 123
 124     /* Parameters.
 125      */
 126     (void)filter_param_register(type, "counter");
 127     (void)filter_param_register(type, "hard_threshold");
 128     (void)filter_param_register(type, "soft_threshold");
 129     return 0;
 130 }
 131 module_init(counter_init);