mdw@git.distorted.org.uk Git - sw-tools/blob - src/sw_env.h

   1 /* -*-c-*-
   2  *
   3  * $Id: sw_env.h,v 1.3 2004/04/08 01:52:19 mdw Exp $
   4  *
   5  * Mangling of environment variables
   6  *
   7  * (c) 1999 EBI
   8  */
   9
  10 /*----- Licensing notice --------------------------------------------------*
  11  *
  12  * This file is part of sw-tools.
  13  *
  14  * sw-tools is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * sw-tools is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with sw-tools; if not, write to the Free Software Foundation,
  26  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  27  */
  28
  29 #ifndef SW_ENV_H
  30 #define SW_ENV_H
  31
  32 #ifdef __cplusplus
  33   extern "C" {
  34 #endif
  35
  36 /*----- Header files ------------------------------------------------------*/
  37
  38 #include <stdio.h>
  39
  40 #include <mLib/dstr.h>
  41 #include <mLib/env.h>
  42 #include <mLib/sym.h>
  43
  44 /*----- Important constants -----------------------------------------------*/
  45
  46 enum {
  47   ENV_OK = 0,                           /* Parsed OK */
  48   ENV_EOF,                              /* End-of-file encountered */
  49   ENV_VCHAR,                            /* Bad character in variable name */
  50   ENV_SUBST,                            /* Bad parameter substitution */
  51   ENV_QUOTE,                            /* Mismatched quote */
  52   ENV_BRACE,                            /* Missing brace character */
  53   ENV_SYSTEM,                           /* System error (see @errno@) */
  54   ENV_INTERNAL                          /* Internal error */
  55 };
  56
  57 enum {
  58   EVF_INCSPC = 1,                       /* Allow spaces in values */
  59   EVF_BACKTICK = 2,                     /* Make backtick self-delimiting */
  60   EVF_SKIP = 4,                         /* Skipping this section of text */
  61   EVF_INITSPC = 8                       /* Allow and ignore leading space */
  62 };
  63
  64 /*----- Functions provided ------------------------------------------------*/
  65
  66 /* --- @env_error@ --- *
  67  *
  68  * Arguments:   @int e@ = error code
  69  *
  70  * Returns:     String representation of error.
  71  *
  72  * Use:         Transforms an error into something a user can understand.
  73  */
  74
  75 extern const char *env_error(int /*e*/);
  76
  77 /* --- @env_var@ --- *
  78  *
  79  * Arguments:   @sym_table *t@ = pointer to symbol table
  80  *              @FILE *fp@ = pointer to stream to read from
  81  *              @dstr *d@ = pointer to output variable
  82  *
  83  * Returns:     One of the @ENV_@ constants.
  84  *
  85  * Use:         Scans a variable name from the input stream.
  86  */
  87
  88 extern int env_var(sym_table */*t*/, FILE */*fp*/, dstr */*d*/);
  89
  90 /* --- @env_value@ --- *
  91  *
  92  * Arguments:   @sym_table *t@ = pointer to symbol table
  93  *              @FILE *fp@ = pointer to stream to read from
  94  *              @dstr *d@ = pointer to output variable
  95  *              @unsigned f@ = various interesting flags
  96  *
  97  * Returns:     0 if OK, @EOF@ if end-of-file encountered, or >0 on error.
  98  *
  99  * Use:         Scans a value from the input stream.  The value read may be
 100  *              quoted in a Bourne-shell sort of a way, and contain Bourne-
 101  *              shell-like parameter substitutions.  Some substitutions
 102  *              aren't available because they're too awkward to implement.
 103  */
 104
 105 extern int env_value(sym_table */*t*/, FILE */*fp*/,
 106                      dstr */*d*/, unsigned /*f*/);
 107
 108 /* --- @env_read@ --- *
 109  *
 110  * Arguments:   @sym_table *t@ = pointer to symbol table
 111  *              @FILE *fp@ = file handle to read
 112  *              @unsigned f@ = various flags
 113  *
 114  * Returns:     Zero if OK, @EOF@ for end-of-file, or error code.
 115  *
 116  * Use:         Reads the environment assignment statements in the file.
 117  */
 118
 119 extern int env_read(sym_table */*t*/, FILE */*fp*/, unsigned /*f*/);
 120
 121 /* --- @env_file@ --- *
 122  *
 123  * Arguments:   @sym_table *t@ = pointer to symbol table
 124  *              @const char *name@ = pointer to filename
 125  *
 126  * Returns:     Zero if OK, or an error code.
 127  *
 128  * Use:         Reads a named file of environment assignments.
 129  */
 130
 131 extern int env_file(sym_table */*t*/, const char */*name*/);
 132
 133 /*----- That's all, folks -------------------------------------------------*/
 134
 135 #ifdef __cplusplus
 136   }
 137 #endif
 138
 139 #endif