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iftop 1.0pre4

    1: /* hash table */
    2: 
    3: #include <stdio.h>
    4: #include <stdlib.h>
    5: #include <string.h>
    6: #include "addr_hash.h"
    7: #include "hash.h"
    8: #include "iftop.h"
    9: 
   10: #define hash_table_size 256
   11: 
   12: int compare(void* a, void* b) {
   13:     addr_pair* aa = (addr_pair*)a;
   14:     addr_pair* bb = (addr_pair*)b;
   15: 
   16:     if (aa->af != bb->af)
   17:         return 0;
   18: 
   19:     if (aa->af == AF_INET6) {
   20:        return (IN6_ARE_ADDR_EQUAL(&aa->src6, &bb->src6)
   21:                && aa->src_port == bb->src_port
   22:                && IN6_ARE_ADDR_EQUAL(&aa->dst6, &bb->dst6)
   23:                && aa->dst_port == bb->dst_port
   24:                && aa->protocol == bb->protocol);
   25:     }
   26: 
   27:     /* AF_INET or unknown. */
   28:     return (aa->src.s_addr == bb->src.s_addr 
   29:             && aa->src_port == bb->src_port
   30:             && aa->dst.s_addr == bb->dst.s_addr
   31:             && aa->dst_port == bb->dst_port
   32:             && aa->protocol == bb->protocol);
   33: }
   34: 
   35: static int __inline__ hash_uint32(uint32_t n) {
   36:     return ((n & 0x000000FF)
   37:             + ((n & 0x0000FF00) >> 8)
   38:             + ((n & 0x00FF0000) >> 16)
   39:             + ((n & 0xFF000000) >> 24));
   40: }
   41: 
   42: int hash(void* key) {
   43:     int hash;
   44:     addr_pair* ap = (addr_pair*)key;
   45: 
   46:     if (ap->af == AF_INET6) {
   47:         uint32_t* addr6 = (uint32_t*)ap->src6.s6_addr;
   48: 
   49:         hash = ( hash_uint32(addr6[0])
   50:                 + hash_uint32(addr6[1])
   51:                 + hash_uint32(addr6[2])
   52:                 + hash_uint32(addr6[3])
   53:                 + ap->src_port) % 0xFF;
   54: 
   55:         addr6 = (uint32_t*)ap->dst6.s6_addr;
   56:         hash = ( hash + hash_uint32(addr6[0])
   57:                 + hash_uint32(addr6[1])
   58:                 + hash_uint32(addr6[2])
   59:                 + hash_uint32(addr6[3])
   60:                 + ap->dst_port) % 0xFF;
   61:     } else {
   62:         in_addr_t addr = ap->src.s_addr;
   63: 
   64:         hash = ( hash_uint32(addr)
   65:                 + ap->src_port) % 0xFF;
   66: 
   67:         addr = ap->dst.s_addr;
   68:         hash = ( hash + hash_uint32(addr)
   69:                 + ap->dst_port) % 0xFF;
   70:     }
   71: 
   72:     return hash;
   73: }
   74: 
   75: void* copy_key(void* orig) {
   76:     addr_pair* copy;
   77:     copy = xmalloc(sizeof *copy);
   78:     *copy = *(addr_pair*)orig;
   79:     return copy;
   80: }
   81: 
   82: void delete_key(void* key) {
   83:     free(key);
   84: }
   85: 
   86: /*
   87:  * Allocate and return a hash
   88:  */
   89: hash_type* addr_hash_create() {
   90:     hash_type* hash_table;
   91:     hash_table = xcalloc(hash_table_size, sizeof *hash_table);
   92:     hash_table->size = hash_table_size;
   93:     hash_table->compare = &compare;
   94:     hash_table->hash = &hash;
   95:     hash_table->delete_key = &delete_key;
   96:     hash_table->copy_key = &copy_key;
   97:     hash_initialise(hash_table);
   98:     return hash_table;
   99: }
  100: