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