Add a -E flag, similar to -e (overide variables from environment) except

that -E only operates for a specified variable.  Useful since the -e option
will often pull-in many unwanted variable overrides (esp. in a make world
situation).  Uses include overriding BINOWN (which cannot be done by normal
methods or through abuses of MAKEFLAGS) or likely for ports to honour CFLAGS
(provided they're running on a system whose make(1) has this option).

4 files changed, 47 insertions, 14 deletions

diff --git a/usr.bin/make/main.c b/usr.bin/make/main.c
index 6b06e68..ea47823 100644
--- a/usr.bin/make/main.c
+++ b/usr.bin/make/main.c
@@ -47,7 +47,7 @@ static const char copyright[] =
 static char sccsid[] = "@(#)main.c	8.3 (Berkeley) 3/19/94";
 #endif
 static const char rcsid[] =
-	"$Id: main.c,v 1.30 1999/03/01 06:01:05 imp Exp $";
+	"$Id: main.c,v 1.31 1999/07/31 20:40:23 hoek Exp $";
 #endif /* not lint */
 
 /*-
@@ -137,6 +137,7 @@ Boolean			beSilent;	/* -s flag */
 Boolean			beVerbose;	/* -v flag */
 Boolean			oldVars;	/* variable substitution style */
 Boolean			checkEnvFirst;	/* -e flag */
+Lst			envFirstVars;	/* (-E) vars to override from env */
 static Boolean		jobsRunning;	/* TRUE if the jobs might be running */
 
 static void		MainParseArgs __P((int, char **));
@@ -173,9 +174,9 @@ MainParseArgs(argc, argv)
 
 	optind = 1;	/* since we're called more than once */
 #ifdef REMOTE
-# define OPTFLAGS "BD:I:L:PSV:d:ef:ij:km:nqrstv"
+# define OPTFLAGS "BD:E:I:L:PSV:d:ef:ij:km:nqrstv"
 #else
-# define OPTFLAGS "BD:I:PSV:d:ef:ij:km:nqrstv"
+# define OPTFLAGS "BD:E:I:PSV:d:ef:ij:km:nqrstv"
 #endif
 rearg:	while((c = getopt(argc, argv, OPTFLAGS)) != -1) {
 		switch(c) {
@@ -279,6 +280,15 @@ rearg:	while((c = getopt(argc, argv, OPTFLAGS)) != -1) {
 			Var_Append(MAKEFLAGS, optarg, VAR_GLOBAL);
 			break;
 		}
+		case 'E':
+			p = malloc(strlen(optarg) + 1);
+			if (!p)
+				Punt("make: cannot allocate memory.");
+			(void)strcpy(p, optarg);
+			(void)Lst_AtEnd(envFirstVars, (ClientData)p);
+			Var_Append(MAKEFLAGS, "-E", VAR_GLOBAL);
+			Var_Append(MAKEFLAGS, optarg, VAR_GLOBAL);
+			break;
 		case 'e':
 			checkEnvFirst = TRUE;
 			Var_Append(MAKEFLAGS, "-e", VAR_GLOBAL);
@@ -599,6 +609,7 @@ main(argc, argv)
 
 	create = Lst_Init(FALSE);
 	makefiles = Lst_Init(FALSE);
+	envFirstVars = Lst_Init(FALSE);
 	printVars = FALSE;
 	variables = Lst_Init(FALSE);
 	beSilent = FALSE;		/* Print commands as executed */
@@ -1295,7 +1306,7 @@ static void
 usage()
 {
 	(void)fprintf(stderr, "%s\n%s\n%s\n",
-"usage: make [-Beiknqrstv] [-D variable] [-d flags] [-f makefile]",
+"usage: make [-Beiknqrstv] [-D variable] [-d flags] [-E variable] [-f makefile]",
 "            [-I directory] [-j max_jobs] [-m directory] [-V variable]",
 "            [variable=value] [target ...]");
 	exit(2);
diff --git a/usr.bin/make/make.1 b/usr.bin/make/make.1
index e4d9833..1b228ce 100644
--- a/usr.bin/make/make.1
+++ b/usr.bin/make/make.1
@@ -30,7 +30,7 @@
 .\" SUCH DAMAGE.
 .\"
 .\"	from: @(#)make.1	8.4 (Berkeley) 3/19/94
-.\"	$Id: make.1,v 1.16 1998/11/29 13:46:39 pds Exp $
+.\"	$Id: make.1,v 1.17 1999/04/19 07:30:03 imp Exp $
 .\"
 .Dd March 19, 1994
 .Dt MAKE 1
@@ -43,6 +43,7 @@
 .Op Fl Beiknqrstv
 .Op Fl D Ar variable
 .Op Fl d Ar flags
+.Op Fl E Ar variable
 .Op Fl f Ar makefile
 .Op Fl I Ar directory
 .Bk -words
@@ -118,9 +119,12 @@ Print debugging information about target list maintenance.
 .It Ar v
 Print debugging information about variable assignment.
 .El
+.It Fl E Ar variable
+Specify a variable whose environment value (if any) will override
+macro assignments within makefiles.
 .It Fl e
-Specify that environment variables override macro assignments within
-makefiles.
+Specify that environment values override macro assignments within
+makefiles for all variables.
 .It Fl f Ar makefile
 Specify a makefile to read instead of the default
 .Ql Pa makefile
diff --git a/usr.bin/make/make.h b/usr.bin/make/make.h
index 52d01db..fad9a9d 100644
--- a/usr.bin/make/make.h
+++ b/usr.bin/make/make.h
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)make.h	8.3 (Berkeley) 6/13/95
- *	$Id: make.h,v 1.7 1997/02/22 19:27:16 peter Exp $
+ *	$Id: make.h,v 1.8 1998/11/14 16:15:04 dg Exp $
  */
 
 /*-
@@ -311,7 +311,10 @@ extern Boolean 	queryFlag;    	/* TRUE if we aren't supposed to really make
 				 * of-date */
 
 extern Boolean	checkEnvFirst;	/* TRUE if environment should be searched for
-				 * variables before the global context */
+				 * all variables before the global context */
+extern Lst	envFirstVars;	/* List of specific variables for which the
+				 * environment should be searched before the
+				 * global context */
 
 extern GNode    *DEFAULT;    	/* .DEFAULT rule */
 
diff --git a/usr.bin/make/var.c b/usr.bin/make/var.c
index 5ae9a1a..92b35b8 100644
--- a/usr.bin/make/var.c
+++ b/usr.bin/make/var.c
@@ -35,7 +35,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	$Id: var.c,v 1.11 1998/06/02 13:11:04 thepish Exp $
+ *	$Id: var.c,v 1.12 1999/04/19 07:30:04 imp Exp $
  */
 
 #ifndef lint
@@ -218,6 +218,7 @@ VarFind (name, ctxt, flags)
 				 * FIND_ENV set means to look in the
 				 * environment */
 {
+    Boolean		localCheckEnvFirst;
     LstNode         	var;
     Var		  	*v;
 
@@ -256,6 +257,20 @@ VarFind (name, ctxt, flags)
 				name = TARGET;
 			break;
 		}
+
+    /*
+     * Note whether this is one of the specific variables we were told through
+     * the -E flag to use environment-variable-override for.
+     */
+    if (Lst_Find (envFirstVars, (ClientData)name,
+		  (int (*)(ClientData, ClientData)) strcmp) != NILLNODE)
+    {
+	localCheckEnvFirst = TRUE;
+    }
+    else {
+	localCheckEnvFirst = FALSE;
+    }
+
     /*
      * First look for the variable in the given context. If it's not there,
      * look for it in VAR_CMD, VAR_GLOBAL and the environment, in that order,
@@ -266,8 +281,8 @@ VarFind (name, ctxt, flags)
     if ((var == NILLNODE) && (flags & FIND_CMD) && (ctxt != VAR_CMD)) {
 	var = Lst_Find (VAR_CMD->context, (ClientData)name, VarCmp);
     }
-    if (!checkEnvFirst && (var == NILLNODE) && (flags & FIND_GLOBAL) &&
-	(ctxt != VAR_GLOBAL))
+    if ((var == NILLNODE) && (flags & FIND_GLOBAL) && (ctxt != VAR_GLOBAL) &&
+	!checkEnvFirst && !localCheckEnvFirst)
     {
 	var = Lst_Find (VAR_GLOBAL->context, (ClientData)name, VarCmp);
     }
@@ -287,8 +302,8 @@ VarFind (name, ctxt, flags)
 
 	    v->flags = VAR_FROM_ENV;
 	    return (v);
-	} else if (checkEnvFirst && (flags & FIND_GLOBAL) &&
-		   (ctxt != VAR_GLOBAL))
+	} else if ((checkEnvFirst || localCheckEnvFirst) &&
+		   (flags & FIND_GLOBAL) && (ctxt != VAR_GLOBAL))
 	{
 	    var = Lst_Find (VAR_GLOBAL->context, (ClientData)name, VarCmp);
 	    if (var == NILLNODE) {