2021-09-27 13:05:35

by Masahiro Yamada

[permalink] [raw]
Subject: [PATCH] kconfig: remove 'const' from the return type of sym_escape_string()

sym_escape_string() returns a malloc'ed memory, so it must be freed
when it is done.

Currently, sym_escape_string() returns the malloc'ed memory as
(const char *), then it is casted to (void *) when it is passed to
free(). This is odd.

The return type of sym_escape_string() should be (char *).

Signed-off-by: Masahiro Yamada <[email protected]>
---

scripts/kconfig/conf.c | 10 +++++-----
scripts/kconfig/confdata.c | 8 ++++----
scripts/kconfig/lkc_proto.h | 2 +-
scripts/kconfig/symbol.c | 3 ++-
4 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/scripts/kconfig/conf.c b/scripts/kconfig/conf.c
index a6dad4a2e7a2..d8e1994bfed0 100644
--- a/scripts/kconfig/conf.c
+++ b/scripts/kconfig/conf.c
@@ -647,15 +647,15 @@ static void check_conf(struct menu *menu)
switch (input_mode) {
case listnewconfig:
if (sym->name) {
- const char *str;
-
if (sym->type == S_STRING) {
+ char *str;
+
str = sym_escape_string(sym);
printf("%s%s=%s\n", CONFIG_, sym->name, str);
- free((void *)str);
+ free(str);
} else {
- str = sym_get_string_value(sym);
- printf("%s%s=%s\n", CONFIG_, sym->name, str);
+ printf("%s%s=%s\n", CONFIG_, sym->name,
+ sym_get_string_value(sym));
}
}
break;
diff --git a/scripts/kconfig/confdata.c b/scripts/kconfig/confdata.c
index 4e053f2477f9..f7eac4beb128 100644
--- a/scripts/kconfig/confdata.c
+++ b/scripts/kconfig/confdata.c
@@ -728,7 +728,7 @@ static struct conf_printer header_printer_cb =
static void conf_write_symbol(FILE *fp, struct symbol *sym,
struct conf_printer *printer, void *printer_arg)
{
- const char *str;
+ char *str;

switch (sym->type) {
case S_UNKNOWN:
@@ -736,11 +736,11 @@ static void conf_write_symbol(FILE *fp, struct symbol *sym,
case S_STRING:
str = sym_escape_string(sym);
printer->print_symbol(fp, sym, str, printer_arg);
- free((void *)str);
+ free(str);
break;
default:
- str = sym_get_string_value(sym);
- printer->print_symbol(fp, sym, str, printer_arg);
+ printer->print_symbol(fp, sym, sym_get_string_value(sym),
+ printer_arg);
}
}

diff --git a/scripts/kconfig/lkc_proto.h b/scripts/kconfig/lkc_proto.h
index 035cc522808b..7ce4b666bba8 100644
--- a/scripts/kconfig/lkc_proto.h
+++ b/scripts/kconfig/lkc_proto.h
@@ -18,7 +18,7 @@ extern struct symbol * symbol_hash[SYMBOL_HASHSIZE];

struct symbol * sym_lookup(const char *name, int flags);
struct symbol * sym_find(const char *name);
-const char * sym_escape_string(struct symbol *sym);
+char *sym_escape_string(struct symbol *sym);
struct symbol ** sym_re_search(const char *pattern);
const char * sym_type_name(enum symbol_type type);
void sym_calc_value(struct symbol *sym);
diff --git a/scripts/kconfig/symbol.c b/scripts/kconfig/symbol.c
index 4a31bb943f79..57189a1ad797 100644
--- a/scripts/kconfig/symbol.c
+++ b/scripts/kconfig/symbol.c
@@ -871,7 +871,8 @@ struct symbol *sym_find(const char *name)
return symbol;
}

-const char *sym_escape_string(struct symbol *sym)
+/* the returned pointer must be freed on the caller side */
+char *sym_escape_string(struct symbol *sym)
{
const char *in, *p;
size_t reslen;
--
2.30.2


2021-09-28 10:07:12

by Nicolas Schier

[permalink] [raw]
Subject: Re: [PATCH] kconfig: remove 'const' from the return type of sym_escape_string()

On Mon, Sep 27, 2021 at 09:59:44PM +0900, Masahiro Yamada wrote:
> sym_escape_string() returns a malloc'ed memory, so it must be freed
> when it is done.
>
> Currently, sym_escape_string() returns the malloc'ed memory as
> (const char *), then it is casted to (void *) when it is passed to
> free(). This is odd.
>
> The return type of sym_escape_string() should be (char *).
>
> Signed-off-by: Masahiro Yamada <[email protected]>

Reviewed-by: Nicolas Schier <[email protected]>

> ---
>
> scripts/kconfig/conf.c | 10 +++++-----
> scripts/kconfig/confdata.c | 8 ++++----
> scripts/kconfig/lkc_proto.h | 2 +-
> scripts/kconfig/symbol.c | 3 ++-
> 4 files changed, 12 insertions(+), 11 deletions(-)
>
> diff --git a/scripts/kconfig/conf.c b/scripts/kconfig/conf.c
> index a6dad4a2e7a2..d8e1994bfed0 100644
> --- a/scripts/kconfig/conf.c
> +++ b/scripts/kconfig/conf.c
> @@ -647,15 +647,15 @@ static void check_conf(struct menu *menu)
> switch (input_mode) {
> case listnewconfig:
> if (sym->name) {
> - const char *str;
> -
> if (sym->type == S_STRING) {
> + char *str;
> +
> str = sym_escape_string(sym);
> printf("%s%s=%s\n", CONFIG_, sym->name, str);
> - free((void *)str);
> + free(str);
> } else {
> - str = sym_get_string_value(sym);
> - printf("%s%s=%s\n", CONFIG_, sym->name, str);
> + printf("%s%s=%s\n", CONFIG_, sym->name,
> + sym_get_string_value(sym));
> }
> }
> break;
> diff --git a/scripts/kconfig/confdata.c b/scripts/kconfig/confdata.c
> index 4e053f2477f9..f7eac4beb128 100644
> --- a/scripts/kconfig/confdata.c
> +++ b/scripts/kconfig/confdata.c
> @@ -728,7 +728,7 @@ static struct conf_printer header_printer_cb =
> static void conf_write_symbol(FILE *fp, struct symbol *sym,
> struct conf_printer *printer, void *printer_arg)
> {
> - const char *str;
> + char *str;
>
> switch (sym->type) {
> case S_UNKNOWN:
> @@ -736,11 +736,11 @@ static void conf_write_symbol(FILE *fp, struct symbol *sym,
> case S_STRING:
> str = sym_escape_string(sym);
> printer->print_symbol(fp, sym, str, printer_arg);
> - free((void *)str);
> + free(str);
> break;
> default:
> - str = sym_get_string_value(sym);
> - printer->print_symbol(fp, sym, str, printer_arg);
> + printer->print_symbol(fp, sym, sym_get_string_value(sym),
> + printer_arg);
> }
> }
>
> diff --git a/scripts/kconfig/lkc_proto.h b/scripts/kconfig/lkc_proto.h
> index 035cc522808b..7ce4b666bba8 100644
> --- a/scripts/kconfig/lkc_proto.h
> +++ b/scripts/kconfig/lkc_proto.h
> @@ -18,7 +18,7 @@ extern struct symbol * symbol_hash[SYMBOL_HASHSIZE];
>
> struct symbol * sym_lookup(const char *name, int flags);
> struct symbol * sym_find(const char *name);
> -const char * sym_escape_string(struct symbol *sym);
> +char *sym_escape_string(struct symbol *sym);
> struct symbol ** sym_re_search(const char *pattern);
> const char * sym_type_name(enum symbol_type type);
> void sym_calc_value(struct symbol *sym);
> diff --git a/scripts/kconfig/symbol.c b/scripts/kconfig/symbol.c
> index 4a31bb943f79..57189a1ad797 100644
> --- a/scripts/kconfig/symbol.c
> +++ b/scripts/kconfig/symbol.c
> @@ -871,7 +871,8 @@ struct symbol *sym_find(const char *name)
> return symbol;
> }
>
> -const char *sym_escape_string(struct symbol *sym)
> +/* the returned pointer must be freed on the caller side */
> +char *sym_escape_string(struct symbol *sym)
> {
> const char *in, *p;
> size_t reslen;
> --
> 2.30.2
>