mdw@git.distorted.org.uk Git - runlisp/blob - common.h

   1 /* -*-c-*-
   2  *
   3  * Common functionality of a less principled nature
   4  *
   5  * (c) 2020 Mark Wooding
   6  */
   7
   8 /*----- Licensing notice --------------------------------------------------*
   9  *
  10  * This file is part of Runlisp, a tool for invoking Common Lisp scripts.
  11  *
  12  * Runlisp is free software: you can redistribute it and/or modify it
  13  * under the terms of the GNU General Public License as published by the
  14  * Free Software Foundation; either version 3 of the License, or (at your
  15  * option) any later version.
  16  *
  17  * Runlisp is distributed in the hope that it will be useful, but WITHOUT
  18  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  19  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  20  * for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with Runlisp.  If not, see <https://www.gnu.org/licenses/>.
  24  */
  25
  26 #ifndef COMMON_H
  27 #define COMMON_H
  28
  29 #ifdef __cplusplus
  30   extern "C" {
  31 #endif
  32
  33 /*----- Externally defined types ------------------------------------------*/
  34
  35 struct dstr;
  36 struct argv;
  37
  38 /*----- Public variables --------------------------------------------------*/
  39
  40 extern struct config config;
  41 extern struct config_section *toplevel, *builtin, *common, *env;
  42 extern unsigned verbose;
  43
  44 /*----- Functions provided ------------------------------------------------*/
  45
  46 extern const char *my_getenv(const char */*name*/, const char */*dflt*/);
  47         /* Look up the environment variable NAME.
  48          *
  49          * If it's found, return the value; otherwise return DFLT.  This
  50          * function looks up the environment variable in the `@ENV'
  51          * configuration section, so (a) it's likely more efficient than
  52          * getenv(3), and (b) the `init_config' function must have been
  53          * called earlier.
  54          */
  55
  56 extern long parse_int(const char */*what*/, const char */*p*/,
  57                       long /*min*/, long /*max*/);
  58         /* Parse and return an integer from the string P.
  59          *
  60          * Report an error if the string doesn't look like an integer, or if
  61          * it's not between MIN and MAX (inclusive).  Qualify error messages
  62          * using the adjective WHAT.
  63          */
  64
  65 extern void argv_string(struct dstr */*d*/, const struct argv */*av*/);
  66         /* Format string-vector AV as a sequence of possibly-quoted words.
  67          *
  68          * Append the resulting list to D.
  69          */
  70
  71 extern int file_exists_p(const char */*path*/, unsigned /*f*/);
  72 #define FEF_EXEC 1u
  73 #define FEF_VERBOSE 2u
  74         /* Return whether PATH names an existing file.
  75          *
  76          * This will return zero if PATH names something which isn't a
  77          * regular file.  If `FEF_EXEC' is set in F, then additionally ensure
  78          * that it's executable by the (real) calling uid.  If `FEF_VERBOSE'
  79          * is set in F, then report on the outcome of the check to standard
  80          * error.
  81          */
  82
  83 extern int found_in_path_p(const char */*prog*/, unsigned /*f*/);
  84         /* Return whether PROG can be found in the `PATH'.
  85          *
  86          * If PROG is a pathname (absolute or relative -- i.e., if it
  87          * contains a `/'), then just check that it names an executable
  88          * program.  Otherwise check to see whether `DIR/PROG' exists and is
  89          * executable for any DIR in the `PATH'.  The flags F are as for
  90          * `file_exists_p'.
  91          */
  92
  93 extern int try_exec(struct argv */*av*/, unsigned /*f*/);
  94 #define TEF_DRYRUN 1u
  95 #define TEF_VERBOSE 2u
  96         /* Try to run a program as indicated by the argument list AV.
  97          *
  98          * This is essentially execvp(3).  If `TEF_VERBOSE' is set in F then
  99          * trace what's going on to standard error.  If `TEF_DRYRUN' is set
 100          * in F then don't actually try to run the program: just check
 101          * whether it exists and is vaguely plausible.  Return -1 if there
 102          * was a problem, or 0 if it was successful but didn't actually run
 103          * the program because of the flags settings.
 104          */
 105
 106 extern void init_config(void);
 107         /* Initialize the configuration machinery.
 108          *
 109          * This establishes the standard configuration sections `@CONFIG',
 110          * `@BUILTIN', `@COMMON', and `@ENV', setting the corresponding
 111          * global variables, and populates `@BUILTIN' (from compile-time
 112          * configuration) and `@ENV' (from the environment variables).
 113          */
 114
 115 extern void read_config_file(const char */*what*/,
 116                              const char */*file*/, unsigned /*f*/);
 117         /* Read a named configuration FILE.
 118          *
 119          * WHAT is an adjective describing the configuration file, to be used
 120          * in diagnostics; FILE is the actual filename to read; and F holds
 121          * `CF_...'  flags for `config_read_file', which actually does most
 122          * of the work.
 123          */
 124
 125 extern void read_config_dir(const char */*what*/,
 126                             const char */*path*/, unsigned /*f*/);
 127         /* Read all of the configuration files in directory PATH.
 128          *
 129          * WHAT is an adjective describing the configuration directory, to be
 130          * used in diagnostics; FILE is the actual filename to read; and F
 131          * holds `CF_...'  flags for `config_read_file', which actually reads
 132          * the files.
 133          *
 134          * All of the files named `*.conf' in the directory are read, in
 135          * ascending lexicographical order by name.  If `CF_NOENTOK' is set
 136          * in F, then ignore an error explaining that the directory doesn't
 137          * exist.  (This only ignores `ENOENT': any other problem is still a
 138          * fatal error.)
 139          */
 140
 141 extern void read_config_path(const char */*path*/, unsigned /*f*/);
 142         /* Read configuration from a file or directory PATH.
 143          *
 144          * If PATH exists and names a directory then process all of the files
 145          * within, as for `read_config_dir'; otherwise try to read it as a
 146          * file, as for `read_config_file'. The flags F are passed to the
 147          * respective function.
 148          */
 149
 150 extern int set_config_var(const char */*assign*/);
 151         /* Apply a configuration variable setting in command-line syntax.
 152          *
 153          * ASSIGN should be a string in the form `[SECT:]VAR=VALUE'.  Set VAR
 154          * to VALUE in section SECT (defaults to `@CONFIG').  The variable is
 155          * set with `CF_OVERRIDE' set to prevent the setting from being
 156          * overwritten by a configuration file.
 157          */
 158
 159 extern void load_default_config(void);
 160         /* Load the default configuration files.
 161          *
 162          * This will read `ETCDIR/runlisp.d/*.conf', `ETCDIR/runlisp.conf',
 163          * `~/.runlisp.conf', and `~/.config/runlisp.conf'.
 164          */
 165
 166 extern void dump_config(void);
 167         /* Dump the configuration to standard error. */
 168
 169 /*----- That's all, folks -------------------------------------------------*/
 170
 171 #ifdef __cplusplus
 172   }
 173 #endif
 174
 175 #endif