src/src/macro.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2018 */
   6 /* See the file NOTICE for conditions of use and distribution. */
   7
   8 /* Functions for handling macros */
   9
  10 #include "exim.h"
  11
  12 #ifdef MACRO_PREDEF
  13 # undef store_get
  14 # define store_get(nbytes) malloc((size_t)(nbytes))
  15 #define string_copyn(s, len) strndup(CS(s), (len))
  16 #endif
  17
  18 /*************************************************
  19 *       Deal with an assignment to a macro       *
  20 *************************************************/
  21
  22 /* We have a new definition; add to the collection.
  23 Items are numbered so we can avoid recursion in expansions.
  24
  25 Args:
  26  name   Name of the macro.  Will be copied.
  27  val    Expansion result for the macro.  Will be copied.
  28 */
  29
  30 macro_item *
  31 macro_create(const uschar * name, const uschar * val, BOOL command_line)
  32 {
  33 int namelen = Ustrlen(name);
  34 macro_item * m = store_get(sizeof(macro_item) + namelen);
  35
  36 /* fprintf(stderr, "%s: '%s' '%s'\n", __FUNCTION__, name, val); */
  37
  38 m->command_line = command_line;
  39 m->namelen = namelen;
  40 m->replen = Ustrlen(val);
  41 m->m_number = m_number++;
  42 memset(&m->tnode, 0, sizeof(tree_node));
  43 /* Use memcpy here not Ustrcpy to avoid spurious compiler-inserted check
  44 when building with fortify-source. We know there is room for the copy into
  45 this dummy for a variable-size array because of the way we did the memory
  46 allocation above. */
  47 memcpy(m->tnode.name, name, namelen+1);
  48 m->tnode.data.ptr = string_copyn(val, m->replen);
  49 (void) tree_insertnode(&tree_macros, &m->tnode);
  50
  51 return m;
  52 }
  53
  54
  55 /* Search for a macro, with an exact match on the name.
  56 Return the node, or NULL for not-found.
  57
  58 Arguments:      name    key to search for
  59 */
  60
  61 macro_item *
  62 macro_search(const uschar * name)
  63 {
  64 tree_node * t;
  65
  66 t = tree_search(tree_macros, name);
  67 return tnode_to_mitem(t);
  68 }
  69
  70
  71 /* Search for a macro with a (possibly improper) leading substring
  72 matching the given name.  Return the node, or NULL for not-found.
  73
  74 Arguments:      name    key to search on
  75 */
  76
  77 macro_item *
  78 macro_search_prefix(const uschar * s)
  79 {
  80 tree_node * t;
  81 int c;
  82
  83 for (t = tree_macros; t; t = c < 0 ? t->left : t->right)
  84   if ((c = Ustrncmp(s, t->name, tnode_to_mitem(t)->namelen)) == 0)
  85     return tnode_to_mitem(t);
  86 return NULL;
  87 }
  88
  89
  90 /* Search for the macro with the largest possible leading substring
  91 matching the given name. */
  92
  93 macro_item *
  94 macro_search_largest_prefix(const uschar * s)
  95 {
  96 macro_item * found;
  97 tree_node * child;
  98 int c;
  99
 100 if ((found = macro_search_prefix(s)))
 101   {
 102   /* There could be a node with a larger substring also matching the
 103   name.  If so it must be in the right subtree; either the right child
 104   or (if that sorts after the name) in the left subtree of the right child. */
 105
 106   child = found->tnode.right;
 107   while (child)
 108     if ((c = Ustrncmp(s, child->name, tnode_to_mitem(child)->namelen)) == 0)
 109       {
 110       found = tnode_to_mitem(child);
 111       child = found->tnode.right;
 112       }
 113     else if (c < 0 && (child = child->left))
 114       continue;
 115     else
 116       break;
 117   }
 118 return found;
 119 }
 120
 121
 122
 123 void
 124 macro_print(uschar * name, uschar * val, void * ctx)
 125 {
 126 BOOL names_only = (BOOL)(long)ctx;
 127 if (names_only)
 128   printf("%s\n", CS name);
 129 else
 130   printf("%s=%s\n", CS name, CS val);
 131 }
 132
 133
 134
 135 /* vi: aw ai sw=2
 136 */
 137 /* End of macro.c */