[1/2] Avoid manual memory management in go-lang.c
Commit Message
I noticed a couple of spots in go-lang.c that could be improved by
using unique_ptr.
---
gdb/dwarf2/read.c | 2 +-
gdb/go-exp.y | 8 ++++----
gdb/go-lang.c | 40 ++++++++++++++++++----------------------
gdb/go-lang.h | 11 ++++++++---
4 files changed, 31 insertions(+), 30 deletions(-)
Comments
Tom Tromey <tom@tromey.com> writes:
> I noticed a couple of spots in go-lang.c that could be improved by
> using unique_ptr.
> ---
> gdb/dwarf2/read.c | 2 +-
> gdb/go-exp.y | 8 ++++----
> gdb/go-lang.c | 40 ++++++++++++++++++----------------------
> gdb/go-lang.h | 11 ++++++++---
> 4 files changed, 31 insertions(+), 30 deletions(-)
>
> diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c
> index eb37c776989..4fd46fd43f8 100644
> --- a/gdb/dwarf2/read.c
> +++ b/gdb/dwarf2/read.c
> @@ -5838,7 +5838,7 @@ fixup_go_packaging (struct dwarf2_cu *cu)
> && sym->aclass () == LOC_BLOCK)
> {
> gdb::unique_xmalloc_ptr<char> this_package_name
> - (go_symbol_package_name (sym));
> + = go_symbol_package_name (sym);
>
> if (this_package_name == NULL)
> continue;
> diff --git a/gdb/go-exp.y b/gdb/go-exp.y
> index 242e7103b94..6aa4c426df6 100644
> --- a/gdb/go-exp.y
> +++ b/gdb/go-exp.y
> @@ -1396,16 +1396,16 @@ classify_name (struct parser_state *par_state, const struct block *block)
> current package. */
>
> {
> - char *current_package_name = go_block_package_name (block);
> + gdb::unique_xmalloc_ptr<char> current_package_name
> + = go_block_package_name (block);
>
> if (current_package_name != NULL)
> {
> struct stoken sval =
> - build_packaged_name (current_package_name,
> - strlen (current_package_name),
> + build_packaged_name (current_package_name.get (),
> + strlen (current_package_name.get ()),
> copy.c_str (), copy.size ());
>
> - xfree (current_package_name);
> sym = lookup_symbol (sval.ptr, block, VAR_DOMAIN,
> &is_a_field_of_this);
> if (sym.symbol)
> diff --git a/gdb/go-lang.c b/gdb/go-lang.c
> index 7549f14dc63..f9176ace71d 100644
> --- a/gdb/go-lang.c
> +++ b/gdb/go-lang.c
> @@ -163,11 +163,8 @@ unpack_package_and_object (char *buf,
>
> Space for the resulting strings is malloc'd in one buffer.
> PACKAGEP,OBJECTP,METHOD_TYPE* will (typically) point into this buffer.
> - [There are a few exceptions, but the caller is still responsible for
> - freeing the resulting pointer.]
> A pointer to this buffer is returned, or NULL if symbol isn't a
> mangled Go symbol.
> - The caller is responsible for freeing the result.
>
> *METHOD_TYPE_IS_POINTERP is set to a boolean indicating if
> the method type is a pointer.
> @@ -180,7 +177,7 @@ unpack_package_and_object (char *buf,
> If we ever need to unpack the method type, this routine should work
> for that too. */
>
> -static char *
> +static gdb::unique_xmalloc_ptr<char>
> unpack_mangled_go_symbol (const char *mangled_name,
> const char **packagep,
> const char **objectp,
> @@ -209,9 +206,10 @@ unpack_mangled_go_symbol (const char *mangled_name,
> /* main.init is mangled specially. */
> if (strcmp (mangled_name, "__go_init_main") == 0)
> {
> - char *package = xstrdup ("main");
> + gdb::unique_xmalloc_ptr<char> package
> + = make_unique_xstrdup ("main");
>
> - *packagep = package;
> + *packagep = package.get ();
> *objectp = "init";
> return package;
> }
> @@ -219,9 +217,10 @@ unpack_mangled_go_symbol (const char *mangled_name,
> /* main.main is mangled specially (missing prefix). */
> if (strcmp (mangled_name, "main.main") == 0)
> {
> - char *package = xstrdup ("main");
> + gdb::unique_xmalloc_ptr<char> package
> + = make_unique_xstrdup ("main");
>
> - *packagep = package;
> + *packagep = package.get ();
> *objectp = "main";
> return package;
> }
> @@ -261,7 +260,8 @@ unpack_mangled_go_symbol (const char *mangled_name,
>
> /* At this point we've decided we have a mangled Go symbol. */
>
> - buf = xstrdup (mangled_name);
> + gdb::unique_xmalloc_ptr<char> result = make_unique_xstrdup (mangled_name);
> + buf = result.get ();
>
> /* Search backwards looking for "N<digit(s)>". */
> p = buf + len;
> @@ -317,7 +317,7 @@ unpack_mangled_go_symbol (const char *mangled_name,
> }
>
> unpack_package_and_object (buf, packagep, objectp);
> - return buf;
> + return result;
> }
>
> /* Implements the la_demangle language_defn routine for language Go.
> @@ -381,10 +381,9 @@ go_language::demangle_symbol (const char *mangled_name, int options) const
> return make_unique_xstrdup ((const char *) obstack_finish (&tempbuf));
> }
>
> -/* Given a Go symbol, return its package or NULL if unknown.
> - Space for the result is malloc'd, caller must free. */
> +/* See go-lang.h. */
>
> -char *
> +gdb::unique_xmalloc_ptr<char>
> go_symbol_package_name (const struct symbol *sym)
> {
> const char *mangled_name = sym->linkage_name ();
> @@ -393,8 +392,7 @@ go_symbol_package_name (const struct symbol *sym)
> const char *method_type_package_name;
> const char *method_type_object_name;
> int method_type_is_pointer;
> - char *name_buf;
> - char *result;
> + gdb::unique_xmalloc_ptr<char> name_buf;
>
> gdb_assert (sym->language () == language_go);
> name_buf = unpack_mangled_go_symbol (mangled_name,
> @@ -405,15 +403,12 @@ go_symbol_package_name (const struct symbol *sym)
> /* Some Go symbols don't have mangled form we interpret (yet). */
> if (name_buf == NULL)
> return NULL;
> - result = xstrdup (package_name);
> - xfree (name_buf);
> - return result;
> + return make_unique_xstrdup (package_name);
> }
>
> -/* Return the package that BLOCK is in, or NULL if there isn't one.
> - Space for the result is malloc'd, caller must free. */
> +/* See go-lang.h. */
>
> -char *
> +gdb::unique_xmalloc_ptr<char>
> go_block_package_name (const struct block *block)
> {
> while (block != NULL)
> @@ -422,7 +417,8 @@ go_block_package_name (const struct block *block)
>
> if (function != NULL)
> {
> - char *package_name = go_symbol_package_name (function);
> + gdb::unique_xmalloc_ptr<char> package_name
> + = go_symbol_package_name (function);
>
> if (package_name != NULL)
> return package_name;
> diff --git a/gdb/go-lang.h b/gdb/go-lang.h
> index 1820b4c9658..877b6175534 100644
> --- a/gdb/go-lang.h
> +++ b/gdb/go-lang.h
> @@ -63,9 +63,14 @@ extern const char *go_main_name (void);
>
> extern enum go_type go_classify_struct_type (struct type *type);
>
> -extern char *go_symbol_package_name (const struct symbol *sym);
> -
> -extern char *go_block_package_name (const struct block *block);
> +/* Given a Go symbol, return its package or NULL if unknown. */
> +extern gdb::unique_xmalloc_ptr<char> go_symbol_package_name
> + (const struct symbol *sym);
> +
> +/* Return the package that BLOCK is in, or NULL if there isn't
> + one. */
> +extern gdb::unique_xmalloc_ptr<char> go_block_package_name
> + (const struct block *block);
Maybe replace NULL with nullptr in these comment. But otherwise, this
all looks great.
Reviewed-By: Andrew Burgess <aburgess@redhat.com>
Thanks,
Andrew
>
> extern const struct builtin_go_type *builtin_go_type (struct gdbarch *);
>
>
> --
> 2.39.1
>> +/* Given a Go symbol, return its package or NULL if unknown. */
>> +extern gdb::unique_xmalloc_ptr<char> go_symbol_package_name
>> + (const struct symbol *sym);
>> +
>> +/* Return the package that BLOCK is in, or NULL if there isn't
>> + one. */
>> +extern gdb::unique_xmalloc_ptr<char> go_block_package_name
>> + (const struct block *block);
Andrew> Maybe replace NULL with nullptr in these comment. But otherwise, this
Andrew> all looks great.
I've done this, thank you.
Tom
@@ -5838,7 +5838,7 @@ fixup_go_packaging (struct dwarf2_cu *cu)
&& sym->aclass () == LOC_BLOCK)
{
gdb::unique_xmalloc_ptr<char> this_package_name
- (go_symbol_package_name (sym));
+ = go_symbol_package_name (sym);
if (this_package_name == NULL)
continue;
@@ -1396,16 +1396,16 @@ classify_name (struct parser_state *par_state, const struct block *block)
current package. */
{
- char *current_package_name = go_block_package_name (block);
+ gdb::unique_xmalloc_ptr<char> current_package_name
+ = go_block_package_name (block);
if (current_package_name != NULL)
{
struct stoken sval =
- build_packaged_name (current_package_name,
- strlen (current_package_name),
+ build_packaged_name (current_package_name.get (),
+ strlen (current_package_name.get ()),
copy.c_str (), copy.size ());
- xfree (current_package_name);
sym = lookup_symbol (sval.ptr, block, VAR_DOMAIN,
&is_a_field_of_this);
if (sym.symbol)
@@ -163,11 +163,8 @@ unpack_package_and_object (char *buf,
Space for the resulting strings is malloc'd in one buffer.
PACKAGEP,OBJECTP,METHOD_TYPE* will (typically) point into this buffer.
- [There are a few exceptions, but the caller is still responsible for
- freeing the resulting pointer.]
A pointer to this buffer is returned, or NULL if symbol isn't a
mangled Go symbol.
- The caller is responsible for freeing the result.
*METHOD_TYPE_IS_POINTERP is set to a boolean indicating if
the method type is a pointer.
@@ -180,7 +177,7 @@ unpack_package_and_object (char *buf,
If we ever need to unpack the method type, this routine should work
for that too. */
-static char *
+static gdb::unique_xmalloc_ptr<char>
unpack_mangled_go_symbol (const char *mangled_name,
const char **packagep,
const char **objectp,
@@ -209,9 +206,10 @@ unpack_mangled_go_symbol (const char *mangled_name,
/* main.init is mangled specially. */
if (strcmp (mangled_name, "__go_init_main") == 0)
{
- char *package = xstrdup ("main");
+ gdb::unique_xmalloc_ptr<char> package
+ = make_unique_xstrdup ("main");
- *packagep = package;
+ *packagep = package.get ();
*objectp = "init";
return package;
}
@@ -219,9 +217,10 @@ unpack_mangled_go_symbol (const char *mangled_name,
/* main.main is mangled specially (missing prefix). */
if (strcmp (mangled_name, "main.main") == 0)
{
- char *package = xstrdup ("main");
+ gdb::unique_xmalloc_ptr<char> package
+ = make_unique_xstrdup ("main");
- *packagep = package;
+ *packagep = package.get ();
*objectp = "main";
return package;
}
@@ -261,7 +260,8 @@ unpack_mangled_go_symbol (const char *mangled_name,
/* At this point we've decided we have a mangled Go symbol. */
- buf = xstrdup (mangled_name);
+ gdb::unique_xmalloc_ptr<char> result = make_unique_xstrdup (mangled_name);
+ buf = result.get ();
/* Search backwards looking for "N<digit(s)>". */
p = buf + len;
@@ -317,7 +317,7 @@ unpack_mangled_go_symbol (const char *mangled_name,
}
unpack_package_and_object (buf, packagep, objectp);
- return buf;
+ return result;
}
/* Implements the la_demangle language_defn routine for language Go.
@@ -381,10 +381,9 @@ go_language::demangle_symbol (const char *mangled_name, int options) const
return make_unique_xstrdup ((const char *) obstack_finish (&tempbuf));
}
-/* Given a Go symbol, return its package or NULL if unknown.
- Space for the result is malloc'd, caller must free. */
+/* See go-lang.h. */
-char *
+gdb::unique_xmalloc_ptr<char>
go_symbol_package_name (const struct symbol *sym)
{
const char *mangled_name = sym->linkage_name ();
@@ -393,8 +392,7 @@ go_symbol_package_name (const struct symbol *sym)
const char *method_type_package_name;
const char *method_type_object_name;
int method_type_is_pointer;
- char *name_buf;
- char *result;
+ gdb::unique_xmalloc_ptr<char> name_buf;
gdb_assert (sym->language () == language_go);
name_buf = unpack_mangled_go_symbol (mangled_name,
@@ -405,15 +403,12 @@ go_symbol_package_name (const struct symbol *sym)
/* Some Go symbols don't have mangled form we interpret (yet). */
if (name_buf == NULL)
return NULL;
- result = xstrdup (package_name);
- xfree (name_buf);
- return result;
+ return make_unique_xstrdup (package_name);
}
-/* Return the package that BLOCK is in, or NULL if there isn't one.
- Space for the result is malloc'd, caller must free. */
+/* See go-lang.h. */
-char *
+gdb::unique_xmalloc_ptr<char>
go_block_package_name (const struct block *block)
{
while (block != NULL)
@@ -422,7 +417,8 @@ go_block_package_name (const struct block *block)
if (function != NULL)
{
- char *package_name = go_symbol_package_name (function);
+ gdb::unique_xmalloc_ptr<char> package_name
+ = go_symbol_package_name (function);
if (package_name != NULL)
return package_name;
@@ -63,9 +63,14 @@ extern const char *go_main_name (void);
extern enum go_type go_classify_struct_type (struct type *type);
-extern char *go_symbol_package_name (const struct symbol *sym);
-
-extern char *go_block_package_name (const struct block *block);
+/* Given a Go symbol, return its package or NULL if unknown. */
+extern gdb::unique_xmalloc_ptr<char> go_symbol_package_name
+ (const struct symbol *sym);
+
+/* Return the package that BLOCK is in, or NULL if there isn't
+ one. */
+extern gdb::unique_xmalloc_ptr<char> go_block_package_name
+ (const struct block *block);
extern const struct builtin_go_type *builtin_go_type (struct gdbarch *);