src/command.h

   1 /*
   2  * Copyright 1994 Christopher Seiwald.
   3  *
   4  * This file is part of Jam - see jam.c for Copyright information.
   5  */
   6 /*
   7  * command.h - the CMD structure and routines to manipulate them
   8  *
   9  * Both ACTION and CMD contain a rule, targets, and sources.  An
  10  * ACTION describes a rule to be applied to the given targets and
  11  * sources; a CMD is what actually gets executed by the shell.  The
  12  * differences are due to:
  13  *
  14  *  ACTIONS must be combined if 'actions together' is given.
  15  *  ACTIONS must be split if 'actions piecemeal' is given.
  16  *  ACTIONS must have current sources omitted for 'actions updated'.
  17  *
  18  * The CMD datatype holds a single command that is to be executed
  19  * against a target, and they can chain together to represent the
  20  * full collection of commands used to update a target.
  21  *
  22  * Structures:
  23  *
  24  *  CMD - an action, ready to be formatted into a buffer and executed
  25  *
  26  * External routines:
  27  *
  28  *  cmd_new() - return a new CMD or 0 if too many args
  29  *  cmd_free() - delete CMD and its parts
  30  *  cmd_next() - walk the CMD chain
  31  */
  32 #ifndef JAMH_COMMAND_H
  33 #define JAMH_COMMAND_H
  34
  35
  36 /*
  37  * CMD - an action, ready to be formatted into a buffer and executed
  38  */
  39 typedef struct _cmd CMD;
  40
  41 struct _cmd {
  42   CMD *next;
  43   CMD *tail;    /* valid on in head */
  44   RULE *rule;    /* rule->actions contains shell script */
  45   LIST *shell;   /* $(SHELL) value */
  46   LOL args;   /* LISTs for $(<), $(>) */
  47   char buf[MAXLINE]; /* actual commands */
  48 };
  49
  50
  51 extern CMD *cmd_new (
  52   RULE *rule,    /* rule (referenced) */
  53   LIST *targets, /* $(<) (freed) */
  54   LIST *sources, /* $(>) (freed) */
  55   LIST *shell,   /* $(SHELL) (freed) */
  56   int maxline);  /* max line length */
  57
  58 extern void cmd_free (CMD *cmd);
  59
  60 #define cmd_next(c)  ((c)->next)
  61
  62
  63 #endif