env: Fix crash when -S string is not empty but no operand follows.

split_spaces() set argc in main() incorrectly, which caused trouble for
getopt().

Examples:
  env -S '\c'
  env -S -i

PR:		197769
MFC after:	1 week

tools/regression/usr.bin/env/regress-env.rgdata

@@ -382,3 +382,36 @@ gblenv=OUTSIDEVAR=OutsideValue
    setenv:D=D_ThisisAlongstring_D1
    stdout:A_ThisisAlongstring_A1 B_ThisisAlongstring_B1 C_ThisisAlongstring_C1 D_ThisisAlongstring_D1 ScriptName: [%-script.pathname-%]
 [run]
+
+[test]
+   sb_args:sh
+   script:[%-testpgm.pathname-%] -S '\c' >/dev/null
+[run]
+[test]
+   sb_args:sh
+   script:[%-testpgm.pathname-%] -S'\c' >/dev/null
+[run]
+[test]
+   sb_args:sh
+   script:[%-testpgm.pathname-%] -u foo -S '\c' >/dev/null
+[run]
+[test]
+   sb_args:sh
+   script:[%-testpgm.pathname-%] -u foo -S'\c' >/dev/null
+[run]
+[test]
+   sb_args:sh
+   script:[%-testpgm.pathname-%] -S '-u bar \c' >/dev/null
+[run]
+[test]
+   sb_args:sh
+   script:[%-testpgm.pathname-%] -S'-u bar \c' >/dev/null
+[run]
+[test]
+   sb_args:sh
+   script:[%-testpgm.pathname-%] -u foo -S '-u bar \c' >/dev/null
+[run]
+[test]
+   sb_args:sh
+   script:[%-testpgm.pathname-%] -u foo -S'-u bar \c' >/dev/null
+[run]

tools/regression/usr.bin/env/regress-sb.rb

@@ -346,6 +346,7 @@ class RGTestOptions
 	#   "just anything" that matches the general pattern.  There are
 	#   no blanks in the recognized values, but I use an x-tended
 	#   regexp and then add blanks to make it more readable.
+	optval.gsub!(/\[%- testpgm\.pathname -%\]/x, $testpgm)
 	optval.gsub!(/\[%- testpgm\.basename -%\]/x, File.basename($testpgm))
 	optval.gsub!(/\[%- script\.pathname  -%\]/x, $scriptfile)
 

usr.bin/env/envopts.c

@@ -372,9 +372,9 @@ split_spaces(const char *str, int *origind, int *origc, char ***origv)
 	*nextarg = NULL;
 
 	/* Update optind/argc/argv in the calling routine */
-	*origind = 1;
-	*origc += addcount;
+	*origc += addcount - *origind + 1;
 	*origv = newargv;
+	*origind = 1;
 }
 
 /**