src/common/container.h

   1 /* Copyright 2003-2004 Roger Dingledine
   2  * Copyright 2004-2007 Roger Dingledine, Nick Mathewson */
   3 /* See LICENSE for licensing information */
   4 /* $Id$ */
   5
   6 #ifndef __CONTAINER_H
   7 #define __CONTAINER_H
   8 #define CONTAINER_H_ID \
   9   "$Id$"
  10
  11 #include "util.h"
  12
  13 /** A resizeable list of pointers, with associated helpful functionality.
  14  *
  15  * The members of this struct are exposed only so that macros and inlines can
  16  * use them; all access to smartlist internals should go throuch the functions
  17  * and macros defined here.
  18  **/
  19 typedef struct smartlist_t {
  20   /** <b>list</b> has enough capacity to store exactly <b>capacity</b> elements
  21    * before it needs to be resized.  Only the first <b>num_used</b> (\<=
  22    * capacity) elements point to valid data.
  23    */
  24   void **list;
  25   int num_used;
  26   int capacity;
  27 } smartlist_t;
  28
  29 smartlist_t *smartlist_create(void);
  30 void smartlist_free(smartlist_t *sl);
  31 void smartlist_set_capacity(smartlist_t *sl, int n);
  32 void smartlist_clear(smartlist_t *sl);
  33 void smartlist_add(smartlist_t *sl, void *element);
  34 void smartlist_add_all(smartlist_t *sl, const smartlist_t *s2);
  35 void smartlist_remove(smartlist_t *sl, const void *element);
  36 void *smartlist_pop_last(smartlist_t *sl);
  37 void smartlist_reverse(smartlist_t *sl);
  38 void smartlist_string_remove(smartlist_t *sl, const char *element);
  39 int smartlist_isin(const smartlist_t *sl, const void *element) ATTR_PURE;
  40 int smartlist_string_isin(const smartlist_t *sl, const char *element)
  41   ATTR_PURE;
  42 int smartlist_string_pos(const smartlist_t *, const char *elt) ATTR_PURE;
  43 int smartlist_string_isin_case(const smartlist_t *sl, const char *element)
  44   ATTR_PURE;
  45 int smartlist_string_num_isin(const smartlist_t *sl, int num) ATTR_PURE;
  46 int smartlist_digest_isin(const smartlist_t *sl, const char *element)
  47   ATTR_PURE;
  48 int smartlist_overlap(const smartlist_t *sl1, const smartlist_t *sl2)
  49   ATTR_PURE;
  50 void smartlist_intersect(smartlist_t *sl1, const smartlist_t *sl2);
  51 void smartlist_subtract(smartlist_t *sl1, const smartlist_t *sl2);
  52
  53 /* smartlist_choose() is defined in crypto.[ch] */
  54 #ifdef DEBUG_SMARTLIST
  55 /** Return the number of items in sl.
  56  */
  57 static INLINE int smartlist_len(const smartlist_t *sl) ATTR_PURE;
  58 static INLINE int smartlist_len(const smartlist_t *sl) {
  59   tor_assert(sl);
  60   return (sl)->num_used;
  61 }
  62 /** Return the <b>idx</b>th element of sl.
  63  */
  64 static INLINE void *smartlist_get(const smartlist_t *sl, int idx) ATTR_PURE;
  65 static INLINE void *smartlist_get(const smartlist_t *sl, int idx) {
  66   tor_assert(sl);
  67   tor_assert(idx>=0);
  68   tor_assert(sl->num_used > idx);
  69   return sl->list[idx];
  70 }
  71 static INLINE void smartlist_set(smartlist_t *sl, int idx, void *val) {
  72   tor_assert(sl);
  73   tor_assert(idx>=0);
  74   tor_assert(sl->num_used > idx);
  75   sl->list[idx] = val;
  76 }
  77 #else
  78 #define smartlist_len(sl) ((sl)->num_used)
  79 #define smartlist_get(sl, idx) ((sl)->list[idx])
  80 #define smartlist_set(sl, idx, val) ((sl)->list[idx] = (val))
  81 #endif
  82
  83 /** Exchange the elements at indices <b>idx1</b> and <b>idx2</b> of the
  84  * smartlist <b>sl</b>. */
  85 static INLINE void smartlist_swap(smartlist_t *sl, int idx1, int idx2)
  86 {
  87   if (idx1 != idx2) {
  88     void *elt = smartlist_get(sl, idx1);
  89     smartlist_set(sl, idx1, smartlist_get(sl, idx2));
  90     smartlist_set(sl, idx2, elt);
  91   }
  92 }
  93
  94 void smartlist_del(smartlist_t *sl, int idx);
  95 void smartlist_del_keeporder(smartlist_t *sl, int idx);
  96 void smartlist_insert(smartlist_t *sl, int idx, void *val);
  97 void smartlist_sort(smartlist_t *sl,
  98                     int (*compare)(const void **a, const void **b));
  99 void smartlist_uniq(smartlist_t *sl,
 100                     int (*compare)(const void **a, const void **b),
 101                     void (*free_fn)(void *elt));
 102 void smartlist_sort_strings(smartlist_t *sl);
 103 void smartlist_sort_digests(smartlist_t *sl);
 104 void smartlist_uniq_strings(smartlist_t *sl);
 105 void smartlist_uniq_digests(smartlist_t *sl);
 106 void *smartlist_bsearch(smartlist_t *sl, const void *key,
 107                         int (*compare)(const void *key, const void **member))
 108  ATTR_PURE;
 109 int smartlist_bsearch_idx(const smartlist_t *sl, const void *key,
 110                           int (*compare)(const void *key, const void **member),
 111                           int *found_out)
 112  ATTR_PURE;
 113
 114 void smartlist_pqueue_add(smartlist_t *sl,
 115                           int (*compare)(const void *a, const void *b),
 116                           void *item);
 117 void *smartlist_pqueue_pop(smartlist_t *sl,
 118                            int (*compare)(const void *a, const void *b));
 119 void smartlist_pqueue_assert_ok(smartlist_t *sl,
 120                                 int (*compare)(const void *a, const void *b));
 121
 122 #define SPLIT_SKIP_SPACE   0x01
 123 #define SPLIT_IGNORE_BLANK 0x02
 124 int smartlist_split_string(smartlist_t *sl, const char *str, const char *sep,
 125                            int flags, int max);
 126 char *smartlist_join_strings(smartlist_t *sl, const char *join, int terminate,
 127                              size_t *len_out) ATTR_MALLOC;
 128 char *smartlist_join_strings2(smartlist_t *sl, const char *join,
 129                               size_t join_len, int terminate, size_t *len_out)
 130   ATTR_MALLOC;
 131
 132 /** Iterate over the items in a smartlist <b>sl</b>, in order.  For each item,
 133  * assign it to a new local variable of type <b>type</b> named <b>var</b>, and
 134  * execute the statement <b>cmd</b>.  Inside the loop, the loop index can
 135  * be accessed as <b>var</b>_sl_idx and the length of the list can be accessed
 136  * as <b>var</b>_sl_len.
 137  *
 138  * NOTE: Do not change the length of the list while the loop is in progress,
 139  * unless you adjust the _sl_len variable correspondingly.  See second example
 140  * below.
 141  *
 142  * Example use:
 143  * <pre>
 144  *   smartlist_t *list = smartlist_split("A:B:C", ":", 0, 0);
 145  *   SMARTLIST_FOREACH(list, char *, cp,
 146  *   {
 147  *     printf("%d: %s\n", cp_sl_idx, cp);
 148  *     tor_free(cp);
 149  *   });
 150  *   smartlist_free(list);
 151  * </pre>
 152  *
 153  * Example use (advanced):
 154  * <pre>
 155  *   SMARTLIST_FOREACH(list, char *, cp,
 156  *   {
 157  *     if (!strcmp(cp, "junk")) {
 158  *       smartlist_del(list, cp_sl_idx);
 159  *       tor_free(cp);
 160  *       --cp_sl_len; // decrement length of list so we don't run off the end
 161  *       --cp_sl_idx; // decrement idx so we consider the item that moved here
 162  *     }
 163  *   });
 164  * </pre>
 165  */
 166 #define SMARTLIST_FOREACH(sl, type, var, cmd)                   \
 167   STMT_BEGIN                                                    \
 168     int var ## _sl_idx, var ## _sl_len=(sl)->num_used;          \
 169     type var;                                                   \
 170     for (var ## _sl_idx = 0; var ## _sl_idx < var ## _sl_len;   \
 171          ++var ## _sl_idx) {                                    \
 172       var = (sl)->list[var ## _sl_idx];                         \
 173       cmd;                                                      \
 174     } STMT_END
 175
 176 /** Helper: While in a SMARTLIST_FOREACH loop over the list <b>sl</b> indexed
 177  * with the variable <b>var</b>, remove the current element in a way that
 178  * won't confuse the loop. */
 179 #define SMARTLIST_DEL_CURRENT(sl, var)          \
 180   STMT_BEGIN                                    \
 181     smartlist_del(sl, var ## _sl_idx);          \
 182     --var ## _sl_idx;                           \
 183     --var ## _sl_len;                           \
 184   STMT_END
 185
 186 #define DECLARE_MAP_FNS(maptype, keytype, prefix)                       \
 187   typedef struct maptype maptype;                                       \
 188   typedef struct prefix##entry_t *prefix##iter_t;                       \
 189   maptype* prefix##new(void);                                           \
 190   void* prefix##set(maptype *map, keytype key, void *val);              \
 191   void* prefix##get(const maptype *map, keytype key);                   \
 192   void* prefix##remove(maptype *map, keytype key);                      \
 193   void prefix##free(maptype *map, void (*free_val)(void*));             \
 194   int prefix##isempty(const maptype *map);                              \
 195   int prefix##size(const maptype *map);                                 \
 196   prefix##iter_t *prefix##iter_init(maptype *map);                      \
 197   prefix##iter_t *prefix##iter_next(maptype *map, prefix##iter_t *iter); \
 198   prefix##iter_t *prefix##iter_next_rmv(maptype *map, prefix##iter_t *iter); \
 199   void prefix##iter_get(prefix##iter_t *iter, keytype *keyp, void **valp); \
 200   int prefix##iter_done(prefix##iter_t *iter);                          \
 201   void prefix##assert_ok(const maptype *map)
 202
 203 /* Map from const char * to void *. Implemented with a hash table. */
 204 DECLARE_MAP_FNS(strmap_t, const char *, strmap_);
 205 DECLARE_MAP_FNS(digestmap_t, const char *, digestmap_);
 206 #undef DECLARE_MAP_FNS
 207
 208 void* strmap_set_lc(strmap_t *map, const char *key, void *val);
 209 void* strmap_get_lc(const strmap_t *map, const char *key);
 210 void* strmap_remove_lc(strmap_t *map, const char *key);
 211
 212 #define DECLARE_TYPED_DIGESTMAP_FNS(prefix, maptype, valtype)           \
 213   typedef struct maptype maptype;                                       \
 214   typedef struct prefix##iter_t prefix##iter_t;                         \
 215   static INLINE maptype* prefix##new(void)                              \
 216   {                                                                     \
 217     return (maptype*)digestmap_new();                                   \
 218   }                                                                     \
 219   static INLINE valtype* prefix##get(maptype *map, const char *key)     \
 220   {                                                                     \
 221     return (valtype*)digestmap_get((digestmap_t*)map, key);             \
 222   }                                                                     \
 223   static INLINE valtype* prefix##set(maptype *map, const char *key,     \
 224                                      valtype *val)                      \
 225   {                                                                     \
 226     return (valtype*)digestmap_set((digestmap_t*)map, key, val);        \
 227   }                                                                     \
 228   static INLINE valtype* prefix##remove(maptype *map, const char *key)  \
 229   {                                                                     \
 230     return (valtype*)digestmap_remove((digestmap_t*)map, key);          \
 231   }                                                                     \
 232   static INLINE void prefix##free(maptype *map, void (*free_val)(void*)) \
 233   {                                                                     \
 234     digestmap_free((digestmap_t*)map, free_val);                        \
 235   }                                                                     \
 236   static INLINE int prefix##isempty(maptype *map)                       \
 237   {                                                                     \
 238     return digestmap_isempty((digestmap_t*)map);                        \
 239   }                                                                     \
 240   static INLINE int prefix##size(maptype *map)                          \
 241   {                                                                     \
 242     return digestmap_size((digestmap_t*)map);                           \
 243   }                                                                     \
 244   static INLINE prefix##iter_t *prefix##iter_init(maptype *map)         \
 245   {                                                                     \
 246     return (prefix##iter_t*) digestmap_iter_init((digestmap_t*)map);    \
 247   }                                                                     \
 248   static INLINE prefix##iter_t *prefix##iter_next(maptype *map,         \
 249                                                   prefix##iter_t *iter) \
 250   {                                                                     \
 251     return (prefix##iter_t*) digestmap_iter_next(                       \
 252                        (digestmap_t*)map, (digestmap_iter_t*)iter);     \
 253   }                                                                     \
 254   static INLINE prefix##iter_t *prefix##iter_next_rmv(maptype *map,     \
 255                                                   prefix##iter_t *iter) \
 256   {                                                                     \
 257     return (prefix##iter_t*) digestmap_iter_next_rmv(                   \
 258                        (digestmap_t*)map, (digestmap_iter_t*)iter);     \
 259   }                                                                     \
 260   static INLINE void prefix##iter_get(prefix##iter_t *iter,             \
 261                                       const char **keyp,                \
 262                                       valtype **valp)                   \
 263   {                                                                     \
 264     void *v;                                                            \
 265     digestmap_iter_get((digestmap_iter_t*) iter, keyp, &v);             \
 266     *valp = v;                                                          \
 267   }                                                                     \
 268   static INLINE int prefix##iter_done(prefix##iter_t *iter)             \
 269   {                                                                     \
 270     return digestmap_iter_done((digestmap_iter_t*)iter);                \
 271   }
 272
 273 #if SIZEOF_INT == 4
 274 #define BITARRAY_SHIFT 5
 275 #elif SIZEOF_INT == 8
 276 #define BITARRAY_SHIFT 6
 277 #else
 278 #error "int is neither 4 nor 8 bytes. I can't deal with that."
 279 #endif
 280 #define BITARRAY_MASK ((1u<<BITARRAY_SHIFT)-1)
 281
 282 /** A random-access array of one-bit-wide elements. */
 283 typedef unsigned int bitarray_t;
 284 /** Create a new bit array that can hold <b>n_bits</b> bits. */
 285 static INLINE bitarray_t *
 286 bitarray_init_zero(int n_bits)
 287 {
 288   size_t sz = (n_bits+BITARRAY_MASK) / (1u << BITARRAY_SHIFT);
 289   return tor_malloc_zero(sz*sizeof(unsigned int));
 290 }
 291 /** Free the bit array <b>ba</b>. */
 292 static INLINE void
 293 bitarray_free(bitarray_t *ba)
 294 {
 295   tor_free(ba);
 296 }
 297 /** Set the <b>bit</b>th bit in <b>b</b> to 1. */
 298 static INLINE void
 299 bitarray_set(bitarray_t *b, int bit)
 300 {
 301   b[bit >> BITARRAY_SHIFT] |= (1u << (bit & BITARRAY_MASK));
 302 }
 303 /** Set the <b>bit</b>th bit in <b>b</b> to 0. */
 304 static INLINE void
 305 bitarray_clear(bitarray_t *b, int bit)
 306 {
 307   b[bit >> BITARRAY_SHIFT] &= ~ (1u << (bit & BITARRAY_MASK));
 308 }
 309 /** Return true iff <b>bit</b>th bit in <b>b</b> is nonzero.  NOTE: does
 310  * not necessarily return 1 on true. */
 311 static INLINE unsigned int
 312 bitarray_is_set(bitarray_t *b, int bit)
 313 {
 314   return b[bit >> BITARRAY_SHIFT] & (1u << (bit & BITARRAY_MASK));
 315 }
 316
 317 /* These functions, given an <b>array</b> of <b>n_elements</b>, return the
 318  * <b>nth</b> lowest element. <b>nth</b>=0 gives the lowest element;
 319  * <b>n_elements</b>-1 gives the highest; and (<b>n_elements</b>-1) / 2 gives
 320  * the median.  As a side effect, the elements of <b>array</b> are sorted. */
 321 int find_nth_int(int *array, int n_elements, int nth);
 322 time_t find_nth_time(time_t *array, int n_elements, int nth);
 323 double find_nth_double(double *array, int n_elements, int nth);
 324 uint32_t find_nth_uint32(uint32_t *array, int n_elements, int nth);
 325 static INLINE int
 326 median_int(int *array, int n_elements)
 327 {
 328   return find_nth_int(array, n_elements, (n_elements-1)/2);
 329 }
 330 static INLINE time_t
 331 median_time(time_t *array, int n_elements)
 332 {
 333   return find_nth_time(array, n_elements, (n_elements-1)/2);
 334 }
 335 static INLINE double
 336 median_double(double *array, int n_elements)
 337 {
 338   return find_nth_double(array, n_elements, (n_elements-1)/2);
 339 }
 340 static INLINE uint32_t
 341 median_uint32(uint32_t *array, int n_elements)
 342 {
 343   return find_nth_uint32(array, n_elements, (n_elements-1)/2);
 344 }
 345
 346 #endif
 347