[src/trunk]: src/usr.bin/make Reviewed by: apb

[sjg <sjg%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/0f9ec796266c
branches:  trunk
changeset: 747285:0f9ec796266c
user:      sjg <sjg%NetBSD.org@localhost>
date:      Tue Sep 08 17:29:20 2009 +0000

description:
Reviewed by: apb

Use .MAKE.LEVEL to track recursion.
The first instance of make will have .MAKE.LEVEL 0, which
can be handy for excluding rules which should not apply
in a sub-make.
gmake and freebsd's make have a similar mechanism, but each
uses a different variable to track it.  Since we cannot be
compatible with both, we allow the makefiles to cope if they want
by handling the export of .MAKE.LEVEL+1 in Var_Set().

diffstat:

 usr.bin/make/main.c |  11 ++++++++---
 usr.bin/make/make.1 |  15 +++++++++++++--
 usr.bin/make/make.h |   3 ++-
 usr.bin/make/var.c  |  23 ++++++++++++++++++++---
 4 files changed, 43 insertions(+), 9 deletions(-)

diffs (143 lines):

diff -r 78bf1c58ea38 -r 0f9ec796266c usr.bin/make/main.c
--- a/usr.bin/make/main.c       Tue Sep 08 17:16:33 2009 +0000
+++ b/usr.bin/make/main.c       Tue Sep 08 17:29:20 2009 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: main.c,v 1.172 2009/09/03 06:45:23 dholland Exp $      */
+/*     $NetBSD: main.c,v 1.173 2009/09/08 17:29:20 sjg Exp $   */
 
 /*
  * Copyright (c) 1988, 1989, 1990, 1993
@@ -69,7 +69,7 @@
  */
 
 #ifndef MAKE_NATIVE
-static char rcsid[] = "$NetBSD: main.c,v 1.172 2009/09/03 06:45:23 dholland Exp $";
+static char rcsid[] = "$NetBSD: main.c,v 1.173 2009/09/08 17:29:20 sjg Exp $";
 #else
 #include <sys/cdefs.h>
 #ifndef lint
@@ -81,7 +81,7 @@
 #if 0
 static char sccsid[] = "@(#)main.c     8.3 (Berkeley) 3/19/94";
 #else
-__RCSID("$NetBSD: main.c,v 1.172 2009/09/03 06:45:23 dholland Exp $");
+__RCSID("$NetBSD: main.c,v 1.173 2009/09/08 17:29:20 sjg Exp $");
 #endif
 #endif /* not lint */
 #endif
@@ -916,7 +916,12 @@
         */
        {
            char tmp[64];
+           const char *ep;
 
+           if (!(ep = getenv(MAKE_LEVEL))) {
+               ep = "0";
+           }
+           Var_Set(MAKE_LEVEL, ep, VAR_GLOBAL, 0);
            snprintf(tmp, sizeof(tmp), "%u", getpid());
            Var_Set(".MAKE.PID", tmp, VAR_GLOBAL, 0);
            snprintf(tmp, sizeof(tmp), "%u", getppid());
diff -r 78bf1c58ea38 -r 0f9ec796266c usr.bin/make/make.1
--- a/usr.bin/make/make.1       Tue Sep 08 17:16:33 2009 +0000
+++ b/usr.bin/make/make.1       Tue Sep 08 17:29:20 2009 +0000
@@ -1,4 +1,4 @@
-.\"    $NetBSD: make.1,v 1.160 2009/08/26 23:18:57 sjg Exp $
+.\"    $NetBSD: make.1,v 1.161 2009/09/08 17:29:20 sjg Exp $
 .\"
 .\" Copyright (c) 1990, 1993
 .\"    The Regents of the University of California.  All rights reserved.
@@ -29,7 +29,7 @@
 .\"
 .\"    from: @(#)make.1        8.4 (Berkeley) 3/19/94
 .\"
-.Dd August 26, 2009
+.Dd September 7, 2009
 .Dt MAKE 1
 .Os
 .Sh NAME
@@ -660,6 +660,17 @@
 .Nm ,
 which is useful for tracking dependencies.
 Each makefile is recorded only once, regardless of the number of times read.
+.It Va .MAKE.LEVEL
+The recursion depth of
+.Nm .
+The initial instance of 
+.Nm
+will be 0, and an incremented value is put into the environment
+to be seen by the next generation.  
+This allows tests like:
+.Li .if ${.MAKE.LEVEL} == 0
+to protect things which should only be evaluated in the initial instance of
+.Nm .
 .It Va .MAKE.PID
 The process-id of
 .Nm .
diff -r 78bf1c58ea38 -r 0f9ec796266c usr.bin/make/make.h
--- a/usr.bin/make/make.h       Tue Sep 08 17:16:33 2009 +0000
+++ b/usr.bin/make/make.h       Tue Sep 08 17:29:20 2009 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: make.h,v 1.78 2009/01/24 14:43:28 dsl Exp $    */
+/*     $NetBSD: make.h,v 1.79 2009/09/08 17:29:20 sjg Exp $    */
 
 /*
  * Copyright (c) 1988, 1989, 1990, 1993
@@ -398,6 +398,7 @@
 #define        MAKE_JOB_PREFIX ".MAKE.JOB.PREFIX" /* prefix for job target output */
 #define        MAKE_EXPORTED   ".MAKE.EXPORTED"   /* variables we export */
 #define        MAKE_MAKEFILES  ".MAKE.MAKEFILES"  /* all the makefiles we read */
+#define        MAKE_LEVEL      ".MAKE.LEVEL"      /* recursion level */
 
 /*
  * debug control:
diff -r 78bf1c58ea38 -r 0f9ec796266c usr.bin/make/var.c
--- a/usr.bin/make/var.c        Tue Sep 08 17:16:33 2009 +0000
+++ b/usr.bin/make/var.c        Tue Sep 08 17:29:20 2009 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: var.c,v 1.153 2009/09/07 17:56:24 sjg Exp $    */
+/*     $NetBSD: var.c,v 1.154 2009/09/08 17:29:20 sjg Exp $    */
 
 /*
  * Copyright (c) 1988, 1989, 1990, 1993
@@ -69,14 +69,14 @@
  */
 
 #ifndef MAKE_NATIVE
-static char rcsid[] = "$NetBSD: var.c,v 1.153 2009/09/07 17:56:24 sjg Exp $";
+static char rcsid[] = "$NetBSD: var.c,v 1.154 2009/09/08 17:29:20 sjg Exp $";
 #else
 #include <sys/cdefs.h>
 #ifndef lint
 #if 0
 static char sccsid[] = "@(#)var.c      8.3 (Berkeley) 3/19/94";
 #else
-__RCSID("$NetBSD: var.c,v 1.153 2009/09/07 17:56:24 sjg Exp $");
+__RCSID("$NetBSD: var.c,v 1.154 2009/09/08 17:29:20 sjg Exp $");
 #endif
 #endif /* not lint */
 #endif
@@ -811,6 +811,23 @@
 
        Var_Append(MAKEOVERRIDES, name, VAR_GLOBAL);
     }
+    /*
+     * Another special case.
+     * Several make's support this sort of mechanism for tracking
+     * recursion - but each uses a different name.
+     * We allow the makefiles to update .MAKE.LEVEL and ensure
+     * children see a correctly incremented value.
+     */
+    if (ctxt == VAR_GLOBAL && strcmp(MAKE_LEVEL, name) == 0) {
+       char tmp[64];
+       int level;
+       
+       level = atoi(val);
+       snprintf(tmp, sizeof(tmp), "%u", level + 1);
+       setenv(MAKE_LEVEL, tmp, 1);
+    }
+       
+       
  out:
     if (expanded_name != NULL)
        free(expanded_name);