From 4703e28188daf3ee335616289d7831e9ab2d4b5f Mon Sep 17 00:00:00 2001
From: "Karl O. Pinc" <kop@karlpinc.com>
Date: Tue, 5 Sep 2023 15:09:33 -0500
Subject: [PATCH] Fiddle with m4 include path resolution

---
 Makefile                                      |  1 +
 README                                        | 15 +++++++++++++++
 db/include/constants.m4                       |  2 +-
 db/include/macros.m4                          |  2 +-
 doc/include/constants.m4                      |  2 +-
 include/{constants.m4 => global_constants.m4} |  4 ++--
 include/{macros.m4 => global_macros.m4}       |  4 ++--
 7 files changed, 23 insertions(+), 7 deletions(-)
 rename include/{constants.m4 => global_constants.m4} (94%)
 rename include/{macros.m4 => global_macros.m4} (93%)

diff --git a/Makefile b/Makefile
index edc0c95..ea06649 100644
--- a/Makefile
+++ b/Makefile
@@ -30,6 +30,7 @@
 #
 MAKE_FILES := make_files
 EMACS_BK_CHR := ~
+export M4_GLOBAL_INCLUDE_PATH := include
 
 # Make "help" be the default target
 include $(MAKE_FILES)/help.mk
diff --git a/README b/README
index a1790a4..5d53daf 100644
--- a/README
+++ b/README
@@ -1 +1,16 @@
 Type "make" in this directory for help on the build system.
+
+Note that while some subdirectories have their own Makefile, all make
+invocations should be from this directory.  All dependencies are not
+guarenteed to be examined otherwise.
+
+
+Notes on the build system:
+
+To maintain sanity with m4 includes, each file within a particular
+branch of the file system directory structure is expected to be
+unique.  This means that it is never necessary for a file to include()
+a file of the same name elsewhere within that branch.  We then supply
+multiple -I arguments to the m4 commands, one for each include
+directory and all m4 include() directives can be file names,
+not qualifed with directory names.
diff --git a/db/include/constants.m4 b/db/include/constants.m4
index b1ca11a..71b328a 100644
--- a/db/include/constants.m4
+++ b/db/include/constants.m4
@@ -28,7 +28,7 @@ dnl   Have m4 discard output generated in this file (see bottom)
 divert(`-1')
 
 dnl Include shared constants
-include(include/constants.m4)
+include(global_constants.m4)
 
 dnl
 dnl General symbols
diff --git a/db/include/macros.m4 b/db/include/macros.m4
index 0623631..425c882 100644
--- a/db/include/macros.m4
+++ b/db/include/macros.m4
@@ -33,7 +33,7 @@ dnl   Have m4 discard output generated in this file (see bottom)
 divert(`-1')
 
 dnl Include standard macros
-include(include/macros.m4)
+include(global_macros.m4)
 
 define(`sdb_generated_sql',
 `-- DO NOT EDIT THIS FILE.  It was automatically generated.  Edit
diff --git a/doc/include/constants.m4 b/doc/include/constants.m4
index 986526d..0ecdb22 100644
--- a/doc/include/constants.m4
+++ b/doc/include/constants.m4
@@ -27,7 +27,7 @@ dnl   Have m4 discard output generated in this file (see bottom)
 divert(`-1')
 
 dnl Include shared constants
-include(include/constants.m4)
+include(global_constants.m4)
 
 dnl
 dnl Symbols for transforming paths to images, which vary by the
diff --git a/include/constants.m4 b/include/global_constants.m4
similarity index 94%
rename from include/constants.m4
rename to include/global_constants.m4
index cc6c14d..b6cc777 100644
--- a/include/constants.m4
+++ b/include/global_constants.m4
@@ -17,11 +17,11 @@ dnl
 dnl
 changequote([{[,]}])dnl m4 foolery so includes include only once.
 dnl                     Once the macro is in the text, change the quotes back
-ifdef([{[_constants.m4]}], [{[changequote(`,')]}], [{[dnl  (see bottom)
+ifdef([{[_global_constants.m4]}], [{[changequote(`,')]}], [{[dnl  (see bottom)
 changequote(`,')dnl
 dnl
 dnl Standard test for having already included the file.
-define(`_constants.m4')dnl
+define(`_global_constants.m4')dnl
 dnl
 dnl   Have m4 discard output generated in this file (see bottom)
 divert(`-1')
diff --git a/include/macros.m4 b/include/global_macros.m4
similarity index 93%
rename from include/macros.m4
rename to include/global_macros.m4
index 2a032c0..b8fcbc9 100644
--- a/include/macros.m4
+++ b/include/global_macros.m4
@@ -22,11 +22,11 @@ dnl
 dnl
 changequote([{[,]}])dnl m4 foolery so includes include only once.
 dnl                     Once the macro is in the text, change the quotes back
-ifdef([{[_macros.m4]}], [{[changequote(`,')]}], [{[dnl  (see bottom)
+ifdef([{[_global_macros.m4]}], [{[changequote(`,')]}], [{[dnl  (see bottom)
 changequote(`,')dnl
 dnl
 dnl Standard test for having already included the file.
-define(`_macros.m4')dnl
+define(`_global_macros.m4')dnl
 dnl
 dnl   Have m4 discard output generated in this file (see bottom)
 divert(`-1')
-- 
2.34.1