src/bpf_symtab.c

   1 /*
   2  * netsniff-ng - the packet sniffing beast
   3  * By Daniel Borkmann <daniel@netsniff-ng.org>
   4  * Copyright 2012 Daniel Borkmann <dborkma@tik.ee.ethz.ch>,
   5  * Swiss federal institute of technology (ETH Zurich)
   6  * Subject to the GPL, version 2.
   7  */
   8
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <string.h>
  12
  13 #include "bpf_symtab.h"
  14 #include "die.h"
  15 #include "xmalloc.h"
  16
  17 struct sym_entry {
  18         char *name;
  19         int type, declared;
  20 };
  21
  22 #define MAX_SYMBOLS     512
  23
  24 static struct sym_entry symbol_table[MAX_SYMBOLS];
  25 static size_t symbol_used = 0;
  26
  27 int bpf_symtab_find(const char *name)
  28 {
  29         int i;
  30
  31         for (i = 0; i < symbol_used; ++i)
  32                 if (!strcmp(symbol_table[i].name, name))
  33                         return i;
  34         return -1;
  35 }
  36
  37 void bpf_symtab_cleanup(void)
  38 {
  39         int i;
  40
  41         for (i = 0; i < symbol_used; ++i)
  42                 xfree(symbol_table[i].name);
  43
  44         symbol_used = 0;
  45 }
  46
  47 int bpf_symtab_insert(const char *name, int type)
  48 {
  49         if (symbol_used >= MAX_SYMBOLS)
  50                 panic("Symbol table overflow, %zu entries!\n", symbol_used);
  51
  52         symbol_table[symbol_used].name = xstrdup(name);
  53         symbol_table[symbol_used].type = type;
  54         symbol_table[symbol_used].declared = 0;
  55
  56         return symbol_used++;
  57 }
  58
  59 int bpf_symtab_type(int idx)
  60 {
  61         if (idx < 0 || idx >= symbol_used)
  62                 return -1;
  63
  64         return symbol_table[idx].type;
  65 }
  66
  67 void bpf_symtab_declare(int idx)
  68 {
  69         if (idx < 0 || idx >= symbol_used)
  70                 return;
  71
  72         symbol_table[idx].declared = 1;
  73 }
  74
  75 int bpf_symtab_declared(int idx)
  76 {
  77         if (idx < 0 || idx >= symbol_used)
  78                 return -1;
  79
  80         return symbol_table[idx].declared;
  81 }
  82
  83 const char *bpf_symtab_name(int idx)
  84 {
  85         if (idx < 0 || idx >= symbol_used)
  86                 return NULL;
  87
  88         return symbol_table[idx].name;
  89 }