Fix import of float attribute/value from environment (re: 960a1a99)

Bug 1: as of 960a1a99, floating point literals were no longer
recognised when importing variables from the environment. The
attribute was still imported but the value reverted to zero:

$ (export LC_NUMERIC=C; typeset -xF5 num=7.75; \
   ksh -c 'typeset -p num')
typeset -x -F 5 num=0.00000

Bug 2 (inherited from 93u+): The code that imported variable
attributes from the environment only checked '.' to determine
whether the float attribute should be set. It should check the
current radix point instead.

$ (export LC_NUMERIC=debug; typeset -xF5 num=7,75; \
   ksh -c 'typeset -p num')
typeset -x -i num=0
...or, after fixing bug 1 only, the output is:
typeset -x -i num=75000

src/cmd/ksh93/sh/arith.c: sh_strnum():
- When importing untrusted env vars at init time, handle not only
  "base#value" literals using strtonll, but also floating point
  literals using strtold. This fixes the bug without reallowing
  arbitary expressions. (re: 960a1a99)
- When not initialising, use sh.radixpoint (see f0386a87) instead
  of '.' to help decide whether to evaluate an arith expression.

src/cmd/ksh93/sh/init.c: env_import_attributes():
- Use sh.radixpoint instead of '.' to check for a decimal fraction.
  (This code is needed because doubles are exported as integers for
  ksh88 compatibility; see attstore() in name.c.)

NEWS

@@ -3,6 +3,11 @@ For full details, see the git log at: https://github.com/ksh93/ksh/tree/1.0
 
 Any uppercase BUG_* names are modernish shell bug IDs.
 
+2022-06-03:
+
+- Fixed a couple of bugs that caused floating point variables imported from
+  a parent ksh through the environment to be corrupted.
+
 2022-06-01:
 
 - New 'typeset' feature inspired by bash (and zsh and mksh): the -g flag

src/cmd/ksh93/include/version.h

@@ -21,7 +21,7 @@
 
 #define SH_RELEASE_FORK	"93u+m"		/* only change if you develop a new ksh93 fork */
 #define SH_RELEASE_SVER	"1.0.0-beta.2"	/* semantic version number: https://semver.org */
-#define SH_RELEASE_DATE	"2022-06-01"	/* must be in this format for $((.sh.version)) */
+#define SH_RELEASE_DATE	"2022-06-03"	/* must be in this format for $((.sh.version)) */
 #define SH_RELEASE_CPYR	"(c) 2020-2022 Contributors to ksh " SH_RELEASE_FORK
 
 /* Scripts sometimes field-split ${.sh.version}, so don't change amount of whitespace. */

src/cmd/ksh93/sh/arith.c

@@ -540,9 +540,12 @@ Sfdouble_t sh_strnum(register const char *str, char** ptr, int mode)
 		d = strtonll(str,&last,&base,-1);
 		if(*last && sh_isstate(SH_INIT))
 		{
-			/* This call is to handle "base#value" literals if we're importing untrusted env vars. */
+			/* Handle floating point or "base#value" literals if we're importing untrusted env vars. */
 			errno = 0;
-			d = strtonll(str, &last, NIL(char*), -1);
+			if(*last==sh.radixpoint)
+				d = strtold(str,&last);
+			else
+				d = strtonll(str,&last,NIL(char*),-1);
 		}
 		if(*last || errno)
 		{
@@ -555,7 +558,7 @@ Sfdouble_t sh_strnum(register const char *str, char** ptr, int mode)
 				d = 0.0;
 			else
 			{
-				if(!last || *last!='.' || last[1]!='.')
+				if(!last || *last!=sh.radixpoint || last[1]!=sh.radixpoint)
 					d = arith_strval(str,&last,arith,mode);
 				if(!ptr && *last && mode>0)
 				{

src/cmd/ksh93/sh/init.c

@@ -2089,17 +2089,17 @@ static void env_import_attributes(char *next)
 				/* check for floating */
 				char *dp, *val = nv_getval(np);
 				strtol(val,&dp,10);
-				if(*dp=='.' || *dp=='e' || *dp=='E')
+				if(*dp==sh.radixpoint || *dp=='e' || *dp=='E')
 				{
 					char *lp;
 					flag |= NV_DOUBLE;
-					if(*dp=='.')
+					if(*dp==sh.radixpoint)
 					{
 						strtol(dp+1,&lp,10);
 						if(*lp)
 							dp = lp;
 					}
-					if(*dp && *dp!='.')
+					if(*dp && *dp!=sh.radixpoint)
 					{
 						flag |= NV_EXPNOTE;
 						size = dp-val;

src/cmd/ksh93/tests/attributes.sh

@@ -787,5 +787,17 @@ got=${got/ -x/}
 [[ $got == "$exp" ]] || err_exit 'typeset -x causes zerofill width to change' \
 	"(expected $(printf %q "$exp"), got $(printf %q "$got"))"
 
+# ======
+# Check import of float attribute/value from environment
+exp='typeset -x -F 5 num=7.75000'
+got=$(typeset -xF5 num=7.75; "$SHELL" -c 'typeset -p num')
+[[ $got == "$exp" ]] || err_exit "floating '.' attribute/value not imported correctly" \
+	"(expected $(printf %q "$exp"), got $(printf %q "$got"))"
+# try again with AST debug locale which has the comma as the radix point
+exp='typeset -x -F 5 num=7,75000'
+got=$(export LC_NUMERIC=debug; typeset -xF5 num=7,75; "$SHELL" -c 'typeset -p num')
+[[ $got == "$exp" ]] || err_exit "floating ',' attribute/value not imported correctly" \
+	"(expected $(printf %q "$exp"), got $(printf %q "$got"))"
+
 # ======
 exit $((Errors<125?Errors:125))