changed C source to use C booleans with backward compatibility

Fix "Under source code control" date for new version.h file.

Sorted the order of symbols printed by "make env".

Test if <stdbool.h> exists and set HAVE_STDBOOL_H accordingly
in have_stdbool.h.  Added HAVE_STDBOOL_H to allow one to force
this value.

Added "bool.h" include file to support use of boolean symbols,
true and false for pre-c99 C compilers.  The "bool.h" include
file defines TRUE as true, FALSE as false, and BOOL as bool:
for backward compatibility.

The sign in a ZVALUE is now of type SIGN, whcih is either
SB32 when CALC2_COMPAT is defined, or a bool.

Replaced in C source, TRUE with true, FALSE with false, and
BOOL with bool.

custom/Makefile

@@ -691,6 +691,7 @@ c_argv.o: ../alloc.h
 c_argv.o: ../attribute.h
 c_argv.o: ../banned.h
 c_argv.o: ../block.h
+c_argv.o: ../bool.h
 c_argv.o: ../byteswap.h
 c_argv.o: ../calc.h
 c_argv.o: ../calcerr.h
@@ -722,6 +723,7 @@ c_devnull.o: ../alloc.h
 c_devnull.o: ../attribute.h
 c_devnull.o: ../banned.h
 c_devnull.o: ../block.h
+c_devnull.o: ../bool.h
 c_devnull.o: ../byteswap.h
 c_devnull.o: ../calcerr.h
 c_devnull.o: ../charbit.h
@@ -753,6 +755,7 @@ c_help.o: ../alloc.h
 c_help.o: ../attribute.h
 c_help.o: ../banned.h
 c_help.o: ../block.h
+c_help.o: ../bool.h
 c_help.o: ../byteswap.h
 c_help.o: ../calcerr.h
 c_help.o: ../charbit.h
@@ -784,6 +787,7 @@ c_pmodm127.o: ../alloc.h
 c_pmodm127.o: ../attribute.h
 c_pmodm127.o: ../banned.h
 c_pmodm127.o: ../block.h
+c_pmodm127.o: ../bool.h
 c_pmodm127.o: ../byteswap.h
 c_pmodm127.o: ../calcerr.h
 c_pmodm127.o: ../charbit.h
@@ -814,6 +818,7 @@ c_pzasusb8.o: ../alloc.h
 c_pzasusb8.o: ../attribute.h
 c_pzasusb8.o: ../banned.h
 c_pzasusb8.o: ../block.h
+c_pzasusb8.o: ../bool.h
 c_pzasusb8.o: ../byteswap.h
 c_pzasusb8.o: ../calcerr.h
 c_pzasusb8.o: ../charbit.h
@@ -844,6 +849,7 @@ c_register.o: ../alloc.h
 c_register.o: ../attribute.h
 c_register.o: ../banned.h
 c_register.o: ../block.h
+c_register.o: ../bool.h
 c_register.o: ../byteswap.h
 c_register.o: ../calc.h
 c_register.o: ../calcerr.h
@@ -875,6 +881,7 @@ c_sysinfo.o: ../alloc.h
 c_sysinfo.o: ../attribute.h
 c_sysinfo.o: ../banned.h
 c_sysinfo.o: ../block.h
+c_sysinfo.o: ../bool.h
 c_sysinfo.o: ../byteswap.h
 c_sysinfo.o: ../calc.h
 c_sysinfo.o: ../calcerr.h
@@ -913,6 +920,7 @@ custtbl.o: ../alloc.h
 custtbl.o: ../attribute.h
 custtbl.o: ../banned.h
 custtbl.o: ../block.h
+custtbl.o: ../bool.h
 custtbl.o: ../byteswap.h
 custtbl.o: ../calcerr.h
 custtbl.o: ../charbit.h

custom/c_pmodm127.c

@@ -70,7 +70,7 @@ ZVALUE p255 = {
 
 /* static declarations */
 S_FUNC void zmod5_or_zmod(ZVALUE *zp);
-STATIC BOOL havelastmod = FALSE;
+STATIC bool havelastmod = false;
 STATIC ZVALUE lastmod[1];
 STATIC ZVALUE lastmodinv[1];
 
@@ -122,14 +122,14 @@ c_pmodm127(char *UNUSED(name), int UNUSED(count), VALUE **vals)
 	if (havelastmod && zcmp(q, *lastmod)) {
 		zfree(*lastmod);
 		zfree(*lastmodinv);
-		havelastmod = FALSE;
+		havelastmod = false;
 	}
 	if (!havelastmod) {
 		zcopy(q, lastmod);
 		zbitvalue(2 * q.len * BASEB, &temp);
 		zquo(temp, q, lastmodinv, 0);
 		zfree(temp);
-		havelastmod = TRUE;
+		havelastmod = true;
 	}
 
 	/*

custom/c_sysinfo.c

@@ -136,8 +136,8 @@ STATIC struct infoname sys_info[] = {
      (FULL)E__COUNT},
     {"E__HIGHEST", "highest calc error", NULL,
      (FULL)E__HIGHEST},
-    {"FALSE", "boolean false", NULL,
-     (FULL)FALSE},
+    {"false", "boolean false", NULL,
+     (FULL)false},
     {"FILEPOS_BITS", "file position size in bits", NULL,
      (FULL)FILEPOS_BITS},
     {"FULL_BITS", "bits in a FULL", NULL,
@@ -248,8 +248,8 @@ STATIC struct infoname sys_info[] = {
      (FULL)TOPHALF},
     {"TOPLONG", "top long bit", NULL,
      (FULL)TOPLONG},
-    {"TRUE", "boolean true", NULL,
-     (FULL)TRUE},
+    {"true", "boolean true", NULL,
+     (FULL)true},
     {"USUAL_ELEMENTS", "usual number of elements for objects", NULL,
      (FULL)USUAL_ELEMENTS},
     {"REGNUM_MAX", "highest custom register number", NULL,

custom/custtbl.c

@@ -39,16 +39,16 @@
  * custom_compiled - determine if custom functions are compiled into libcustcalc
  *
  * returns:
-s*	TRUE  ==> libcustcalc was compiled with CUSTOM defined
- *	FALSE ==> libcustcalc was compiled with CUSTOM undefined
+s*	true  ==> libcustcalc was compiled with CUSTOM defined
+ *	false ==> libcustcalc was compiled with CUSTOM undefined
  */
-E_FUNC BOOL
+E_FUNC bool
 custom_compiled(void)
 {
 #if defined(CUSTOM)
-	return TRUE;
+	return true;
 #else /* CUSTOM */
-	return FALSE;
+	return false;
 #endif /* CUSTOM */
 }