macro.c

操作系统源代码

/*************************************************************************
 *
 *  m a k e :   m a c r o . c
 *
 *  Macro control for make
 *========================================================================
 * Edition history
 *
 *  #    Date                         Comments                       By
 * --- -------- ---------------------------------------------------- ---
 *   1    ??                                                         ??
 *   2 23.08.89 Error message corrected                              RAL
 *   3 30.08.89 macro flags added, indention ch.                     PSH,RAL
 *   4 03.09.89 fixed LZ eliminated, doexp(...) changed              RAL
 *   5 06.09.89 M_MAKE added, setDFmacro added                       RAL
 *   6 20.09.89 work around for Minix PC ACK bug                     BE,RAL
 * ------------ Version 2.0 released ------------------------------- RAL
 *
 *************************************************************************/

#include "h.h"


static char   buf[256];

struct macro *getmp(name)
char *name;
{
  register struct macro *rp;

  for (rp = macrohead; rp; rp = rp->m_next)
		if (strcmp(name, rp->m_name) == 0)
			return rp;
  return (struct macro *)0;
}


char *getmacro(name)
char *name;
{
  struct macro *mp;

  if (mp = getmp(name))
		return mp->m_val;
/*	else*/
		return "";
}


struct macro *setmacro(name, val)
char *name;
char *val;
{
  register struct macro *rp;
  register char         *cp;


		/*  Replace macro definition if it exists  */
  for (rp = macrohead; rp; rp = rp->m_next)
	if (strcmp(name, rp->m_name) == 0) {
		if(rp->m_flag & M_OVERRIDE) return rp;	/* mustn't change */
		free(rp->m_val);	/*  Free space from old  */
		break;
		}

	if (!rp)		/*  If not defined, allocate space for new  */
	{
		if ((rp = (struct macro *)malloc(sizeof (struct macro)))
					 == (struct macro *)0)
			fatal("No memory for macro",(char *)0,0);

		rp->m_next = macrohead;
		macrohead = rp;
		rp->m_flag = FALSE;

		if ((cp = (char *) malloc(strlen(name)+1)) == (char *)0)
			fatal("No memory for macro",(char *)0,0);
		strcpy(cp, name);
		rp->m_name = cp;
	}

	if ((cp = (char *) malloc(strlen(val)+1)) == (char *)0)
		fatal("No memory for macro",(char *)0,0);
	strcpy(cp, val);		/*  Copy in new value  */
	rp->m_val = cp;

  return rp;
}


void setDFmacro(name, val)
char *name;
char *val;
{
  char        *c,*tmp;
  int          len;
  static char  filename[]="@F";
  static char  dirname[] ="@D";

  setmacro(name,val);
  *filename = *name;
  *dirname  = *name;
  /* Null string -- not defined macro */
  if ( !(*val)) {
     setmacro(filename,"");
     setmacro(dirname,"");
     return;
  }
  if (!(c = strrchr(val,(int)'/'))) {
     setmacro(filename,val);
     setmacro(dirname,"./");
     return;
  }
  setmacro(filename,c+1);
  len = c - val + 1;
  if((tmp = (char *) malloc(len + 1)) == (char *) 0)
     fatal("No memory for tmp",(char *)0,0);
  strncpy(tmp,val,len);
  tmp[len] = '\0';
  setmacro(dirname,tmp);
  free(tmp);
  return;
}

/*
 *	Do the dirty work for expand
 */
void doexp(to, from)
struct str *to;
char  *from;
{
  register char *rp;
  register char *p;
  char *q;
  struct macro *mp;
  int temp;			/* work-around for ACK bug (PC)*/


  rp  = from;
  temp= to->pos;
  p   = &(*to->ptr)[temp];
  while (*rp) {
	if (*rp != '$') {
		*p++ = *rp++;
		to->pos++;
	}
	else {
		q = buf;
		if (*++rp == '{')
			while (*++rp && *rp != '}')
				*q++ = *rp;
		else if (*rp == '(')
			while (*++rp && *rp != ')')
				*q++ = *rp;
		else if (!*rp) {
			*p++ = '$';
			to->pos++;
			break;
		}
		else
			*q++ = *rp;
		*q = '\0';
		if (*rp)
			rp++;
		if (!(mp = getmp(buf)))
			mp = setmacro(buf, "");
		if (mp->m_flag & M_MARK)
			fatal("Infinitely recursive macro %s", mp->m_name,0);
		mp->m_flag |= M_MARK;
		if ( mp->m_flag & M_MAKE) expmake = TRUE;
		doexp(to, mp->m_val);
		temp = to->pos;
		p = &(*to->ptr)[temp];
		mp->m_flag &= ~M_MARK;
	}
	if (to->pos >= to->len) {
		strrealloc (to);
		temp = to->pos;
		p =  &(*to->ptr)[temp];
	}
  }
  *p = '\0';
}


/*
 *	Expand any macros in str.
 */
void expand(strs)
struct str *strs;
{
  char  *a;

  if ((a = (char *) malloc(strlen(*strs->ptr)+1)) == (char *)0)
     fatal("No memory for temporary string",(char *)0,0);
  strcpy(a, *strs->ptr);
  strs->pos = 0;
  doexp(strs, a);
  free(a);
}