shared source/sscli20/tools/nmake/macro.cpp

   1 // ==++==
   2 //
   3 //
   4 //    Copyright (c) 2006 Microsoft Corporation.  All rights reserved.
   5 //
   6 //    The use and distribution terms for this software are contained in the file
   7 //    named license.txt, which can be found in the root of this distribution.
   8 //    By using this software in any fashion, you are agreeing to be bound by the
   9 //    terms of this license.
  10 //
  11 //    You must not remove this notice, or any other, from this software.
  12 //
  13 //
  14 // ==--==
  15 //  Macro.C - contains routines that have to do with macros
  16 //
  17 // Purpose:
  18 //  Contains routines that have to do with macros
  19
  20 #include "precomp.h"
  21 #ifdef _MSC_VER
  22 #pragma hdrstop
  23 #endif
  24
  25 static STRINGLIST **lastMacroChain = NULL;
  26
  27 // findMacro - look up a string in a hash table
  28 //
  29 //  Look up a macro name in a hash table and return the entry
  30 //  or NULL.
  31 //  If a macro and undefined, return NULL.
  32
  33 MACRODEF * findMacro(char *str)
  34 {
  35     unsigned n;
  36     char *string = str;
  37     STRINGLIST *found;
  38
  39     if (*string) {
  40         for (n = 0; *string; n += *string++);           //Hash
  41         n %= MAXMACRO;
  42 #if defined(STATISTICS)
  43         CntfindMacro++;
  44 #endif
  45         lastMacroChain = (STRINGLIST **)&macroTable[n];
  46         for (found = *lastMacroChain; found; found = found->next) {
  47 #if defined(STATISTICS)
  48             CntmacroChains++;
  49 #endif
  50             if (!_tcscmp(found->text, str)) {
  51                 return((((MACRODEF *)found)->flags & M_UNDEFINED) ? NULL : (MACRODEF *)found);
  52             }
  53         }
  54     } else {
  55         // set lastMacroChain, even for an empty name
  56         lastMacroChain = (STRINGLIST **)&macroTable[0];
  57     }
  58     return(NULL);
  59 }
  60
  61 // insertMacro
  62 //
  63 // Macro insertion requires that we JUST did a findMacro, which action set lastMacroChain.
  64
  65 void insertMacro(STRINGLIST * p)
  66 {
  67 #ifdef STATISTICS
  68     CntinsertMacro++;
  69 #endif
  70     assert(lastMacroChain != NULL);
  71     prependItem(lastMacroChain, p);
  72     lastMacroChain = NULL;
  73 }
  74
  75 // Init the macro table to a known state before continuing.
  76
  77 void initMacroTable(MACRODEF *table[])
  78 {
  79     unsigned num;
  80     for (num = 0; num < MAXMACRO; num++) {
  81         table[num] = NULL;
  82     }
  83 }