kbuild: do not quote string values in include/config/auto.conf

The previous commit fixed up all shell scripts to not include
include/config/auto.conf.

Now that include/config/auto.conf is only included by Makefiles,
we can change it into a more Make-friendly form.

Previously, Kconfig output string values enclosed with double-quotes
(both in the .config and include/config/auto.conf):

    CONFIG_X="foo bar"

Unlike shell, Make handles double-quotes (and single-quotes as well)
verbatim. We must rip them off when used.

There are some patterns:

  [1] $(patsubst "%",%,$(CONFIG_X))
  [2] $(CONFIG_X:"%"=%)
  [3] $(subst ",,$(CONFIG_X))
  [4] $(shell echo $(CONFIG_X))

These are not only ugly, but also fragile.

[1] and [2] do not work if the value contains spaces, like
   CONFIG_X=" foo bar "

[3] does not work correctly if the value contains double-quotes like
   CONFIG_X="foo\"bar"

[4] seems to work better, but has a cost of forking a process.

Anyway, quoted strings were always PITA for our Makefiles.

This commit changes Kconfig to stop quoting in include/config/auto.conf.

These are the string type symbols referenced in Makefiles or scripts:

    ACPI_CUSTOM_DSDT_FILE
    ARC_BUILTIN_DTB_NAME
    ARC_TUNE_MCPU
    BUILTIN_DTB_SOURCE
    CC_IMPLICIT_FALLTHROUGH
    CC_VERSION_TEXT
    CFG80211_EXTRA_REGDB_KEYDIR
    EXTRA_FIRMWARE
    EXTRA_FIRMWARE_DIR
    EXTRA_TARGETS
    H8300_BUILTIN_DTB
    INITRAMFS_SOURCE
    LOCALVERSION
    MODULE_SIG_HASH
    MODULE_SIG_KEY
    NDS32_BUILTIN_DTB
    NIOS2_DTB_SOURCE
    OPENRISC_BUILTIN_DTB
    SOC_CANAAN_K210_DTB_SOURCE
    SYSTEM_BLACKLIST_HASH_LIST
    SYSTEM_REVOCATION_KEYS
    SYSTEM_TRUSTED_KEYS
    TARGET_CPU
    UNUSED_KSYMS_WHITELIST
    XILINX_MICROBLAZE0_FAMILY
    XILINX_MICROBLAZE0_HW_VER
    XTENSA_VARIANT_NAME

I checked them one by one, and fixed up the code where necessary.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

1 files changed, 13 insertions, 11 deletions

diff --git a/scripts/kconfig/confdata.c b/scripts/kconfig/confdata.c
index 42bc56ee238c..59717be31210 100644
--- a/scripts/kconfig/confdata.c
+++ b/scripts/kconfig/confdata.c
@@ -244,19 +244,21 @@ static int conf_set_sym_val(struct symbol *sym, int def, int def_flags, char *p)
 				     p, sym->name);
 		return 1;
 	case S_STRING:
-		if (*p++ != '"')
-			break;
-		for (p2 = p; (p2 = strpbrk(p2, "\"\\")); p2++) {
-			if (*p2 == '"') {
-				*p2 = 0;
+		/* No escaping for S_DEF_AUTO (include/config/auto.conf) */
+		if (def != S_DEF_AUTO) {
+			if (*p++ != '"')
 				break;
+			for (p2 = p; (p2 = strpbrk(p2, "\"\\")); p2++) {
+				if (*p2 == '"') {
+					*p2 = 0;
+					break;
+				}
+				memmove(p2, p2 + 1, strlen(p2));
 			}
-			memmove(p2, p2 + 1, strlen(p2));
-		}
-		if (!p2) {
-			if (def != S_DEF_AUTO)
+			if (!p2) {
 				conf_warning("invalid string found");
-			return 1;
+				return 1;
+			}
 		}
 		/* fall through */
 	case S_INT:
@@ -700,7 +702,7 @@ static void print_symbol_for_dotconfig(FILE *fp, struct symbol *sym)
 
 static void print_symbol_for_autoconf(FILE *fp, struct symbol *sym)
 {
-	__print_symbol(fp, sym, OUTPUT_N_NONE, true);
+	__print_symbol(fp, sym, OUTPUT_N_NONE, false);
 }
 
 void print_symbol_for_listconfig(struct symbol *sym)