iconv: Suppress intermediate errors with //TRANSLIT (bug 34236)

When tentatively converting characters on behalf of
__gconv_transliterate, do not create a persistent error.  Just
produce a local error, and rely on __gconv_transliterate to
produce the error if all transliteration options are exhausted.

This fixes transliteration of “½” to ASCII, which cannot use the
“ 1⁄2 ” alternative.  Eventually, the “ 1/2 ” alternative is chosen,
but the error sticks.  Therefore, iconv exited with status 1 before
this change.

Adjust iconv/tst-iconv_prog.sh to test both C and en_US.UTF-8 locales.
This requires changing the way the ICONV template is defined, so that
run_program_env is evaluated multiple times.

Fixes commit 9a4b0eaf72 ("iconv: do not
report error exit with transliteration [BZ #32448]"),
commit 6cbf845fcd ("iconv: Preserve
iconv -c error exit on invalid inputs (bug 32046)"), and bug 34236.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>

iconv/Makefile

@@ -139,7 +139,8 @@ $(objpfx)test-iconvconfig.out: $(objpfx)iconvconfig
 	 rm -f $$tmp) > $@; \
 	$(evaluate-test)
 
-$(objpfx)tst-iconv_prog.out: tst-iconv_prog.sh $(objpfx)iconv_prog
+$(objpfx)tst-iconv_prog.out: tst-iconv_prog.sh $(objpfx)iconv_prog \
+  $(gen-locales)
 	$(BASH) $< $(common-objdir) '$(test-wrapper-env)' \
 		 '$(run-program-env)' '$(rpath-link)' > $@; \
 	$(evaluate-test)

iconv/loop.c

@@ -144,8 +144,10 @@
     if (irreversible == NULL)						      \
       {									      \
 	/* This means we are in call from __gconv_transliterate.  In this     \
-	   case we are not doing any error recovery ourselves.  */	      \
-	result = __gconv_mark_illegal_input (step_data);		      \
+	   case we are not doing any error recovery ourselves.  Do not create \
+	   a persistent error state.  If __gconv_transliterate exhausts all   \
+	   alternatives, it will call __gconv_mark_illegal_input itself.  */  \
+	result = __GCONV_ILLEGAL_INPUT;					      \
 	break;								      \
       }									      \
 									      \

iconv/tst-iconv_prog.sh

@@ -29,10 +29,10 @@ LIBPATH=$codir:$codir/iconvdata
 
 # How the start the iconv(1) program.  $from is not defined/expanded yet.
 ICONV='
+$test_wrapper_env $run_program_env
 $codir/elf/ld.so --library-path $library_path:$LIBPATH --inhibit-rpath ${from}.so
 $codir/iconv/iconv_prog
 '
-ICONV="$test_wrapper_env $run_program_env $ICONV"
 
 TIMEOUTFACTOR=${TIMEOUTFACTOR:-1}
 
@@ -220,6 +220,7 @@ testarray=(
 "\x00\x00;;INVALID;UTF-8;1"
 "\x00\x00;;UTF-8;INVALID;1"
 "\xc3\xa9;;UTF-8;ASCII//TRANSLIT;0"
+"X\xc2\xbdY;;UTF-8;ASCII//TRANSLIT;0"
 )
 
 # Requires $twobyte input, $c flag, $from, and $to to be set; sets $ret
@@ -280,7 +281,9 @@ check_errtest_result ()
   fi
 }
 
-for testcommand in "${testarray[@]}"; do
+run_test_array ()
+{
+  for testcommand in "${testarray[@]}"; do
     twobyte="$(echo "$testcommand" | cut -d";" -f 1)"
     c="$(echo "$testcommand" | cut -d";" -f 2)"
     from="$(echo "$testcommand" | cut -d";" -f 3)"
@@ -288,4 +291,11 @@ for testcommand in "${testarray[@]}"; do
     eret="$(echo "$testcommand" | cut -d";" -f 5)"
     execute_test
     check_errtest_result
-done
+  done
+}
+
+echo "info: testing C locale"
+run_test_array
+echo "info: testing en_US.UTF-8 locale"
+run_program_env="$run_program_env LC_ALL=en_US.UTF-8"
+run_test_array