string_pool.c

   1 #include <string.h>
   2
   3 #include "trp.h"
   4 #include "obj_pool.h"
   5 #include "string_pool.h"
   6
   7 typedef struct node_s node_t;
   8
   9 struct node_s {
  10     uint32_t offset;
  11      trp_node(node_t) children;
  12 };
  13
  14 typedef trp(node_t) tree_t;
  15
  16 static tree_t tree = { ~0 };
  17
  18 obj_pool_gen(node, node_t, 4096);
  19 obj_pool_gen(string, char, 4096);
  20
  21 static char *node_value(node_t * node)
  22 {
  23     return node ? string_pointer(node->offset) : NULL;
  24 }
  25
  26 static int node_value_cmp(node_t * a, node_t * b)
  27 {
  28     return strcmp(node_value(a), node_value(b));
  29 }
  30
  31 static int node_indentity_cmp(node_t * a, node_t * b)
  32 {
  33     int r = node_value_cmp(a, b);
  34     return r ? r : (((uintptr_t) a) > ((uintptr_t) b))
  35         - (((uintptr_t) a) < ((uintptr_t) b));
  36 }
  37
  38 trp_gen(static, tree_, tree_t, node_t, children, node,
  39         node_indentity_cmp);
  40
  41 static char *pool_fetch(uint32_t entry)
  42 {
  43     return node_value(node_pointer(entry));
  44 }
  45
  46 uint32_t pool_intern(char *key)
  47 {
  48     node_t *match = NULL;
  49     uint32_t key_len = strlen(key) + 1;
  50     node_t *node = node_pointer(node_alloc(1));
  51     node->offset = string_alloc(key_len);
  52     strcpy(node_value(node), key);
  53     match = tree_psearch(&tree, node);
  54     if (!match || node_value_cmp(node, match)) {
  55         tree_insert(&tree, node);
  56     } else {
  57         node_free(1);
  58         string_free(key_len);
  59         node = match;
  60     }
  61     return node_offset(node);
  62 }
  63
  64 uint32_t pool_tok_r(char *str, const char *delim, char **saveptr)
  65 {
  66     char *token = strtok_r(str, delim, saveptr);
  67     return token ? pool_intern(token) : ~0;
  68 }
  69
  70 void pool_print_seq(uint32_t len, uint32_t * seq, char delim, FILE * stream)
  71 {
  72     uint32_t i;
  73     for (i = 0; i < len; i++) {
  74         fputs(pool_fetch(seq[i]), stream);
  75         if (i < len - 1)
  76             fputc(delim, stream);
  77     }
  78 }
  79
  80 void pool_reset(void)
  81 {
  82     node_reset();
  83     string_reset();
  84 }