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