gcc/pcp.h

   1 /* pcp.h -- Describes the format of a precompiled file
   2    Copyright (C) 1990 Free Software Foundation, Inc.
   3
   4 This file is part of GNU CC.
   5
   6 GNU CC is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU CC is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU CC; see the file COPYING.  If not, write to
  18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20
  21
  22 /* Structure allocated for every string in a precompiled file */
  23 typedef struct stringdef STRINGDEF;
  24 struct stringdef
  25 {
  26   U_CHAR *contents;             /* String to include */
  27   int len;                      /* Its length */
  28   int writeflag;                /* Whether we write this */
  29   int lineno;                   /* Linenumber of source file */
  30   U_CHAR *filename;             /* Name of source file */
  31   STRINGDEF *chain;             /* Global list of strings in natural order */
  32   int output_mark;              /* Where in the output this goes */
  33 };
  34
  35 typedef struct keydef KEYDEF;
  36 struct keydef
  37 {
  38   STRINGDEF *str;
  39   KEYDEF *chain;
  40 };
  41
  42 /* Format: */
  43 /* A precompiled file starts with a series of #define and #undef
  44  statements:
  45     #define MAC DEF     ---   Indicates MAC must be defined with defn DEF
  46     #define MAC         ---   Indicates MAC must be defined with any defn
  47     #undef MAC          ---   Indicates MAC cannot be defined
  48
  49 These preconditions must be true for a precompiled file to be used.
  50 The preconditions section is null terminated. */
  51
  52 /* Then, there is a four byte number (in network byte order) which */
  53  /* indicates the number of strings the file contains. */
  54
  55 /* Each string contains a STRINGDEF structure.  The only component of */
  56  /* the STRINGDEF structure which is used is the lineno field, which */
  57  /* should hold the line number in the original header file.  */
  58  /* Then follows the string, followed by a null.  Then comes a four */
  59  /* byte number (again, in network byte order) indicating the number */
  60  /* of keys for this string.  Each key is a KEYDEF structure, with */
  61  /* irrelevant contents, followed by the null-terminated string. */
  62
  63 /* If the number of keys is 0, then there are no keys for the string, */
  64  /* in other words, the string will never be included.  If the number */
  65  /* of keys is -1, this is a special flag indicating there are no keys */
  66  /* in the file, and the string is mandatory (that is, it must be */
  67  /* included regardless in the included output).  */
  68
  69 /* A file, then, looks like this:
  70
  71   Precondition 1
  72   Precondition 2
  73   .
  74   .
  75   .
  76   <NUL>
  77   Number of strings
  78     STRINGDEF
  79     String . . . <NUL>
  80     Number of keys
  81       KEYDEF
  82       Key . . . <NUL>
  83       KEYDEF
  84       Key . . . <NUL>
  85       .
  86       .
  87       .
  88     STRINGDEF
  89     String . . . <NUL>
  90     Number of keys
  91       KEYDEF
  92       Key . . . <NUL>
  93       .
  94       .
  95       .
  96     .
  97     .
  98     .
  99
 100 */