On December 14, 2021 2:50:15 PM GMT-03:00, Douglas Raillard <douglas.raillard@xxxxxxx> wrote:
>On 12/14/21 2:55 PM, Arnaldo Carvalho de Melo wrote:
>> Em Tue, Dec 07, 2021 at 05:31:49PM +0000, Douglas RAILLARD escreveu:
>>> From: Douglas Raillard <douglas.raillard@xxxxxxx>
>>>
>>> Add the prefix specified by --expanded_prefix to type names that have
>>> not been specificaly requested using -C. This allows manual namespacing
>>> so that these inner types will not conflict with existing headers.
>>>
>>> Signed-off-by: Douglas Raillard <douglas.raillard@xxxxxxx>
>>> ---
>>> dwarves.h | 1 +
>>> pahole.c | 29 +++++++++++++++++++++++++++--
>>> 2 files changed, 28 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/dwarves.h b/dwarves.h
>>> index fc5b3fa..0967e5c 100644
>>> --- a/dwarves.h
>>> +++ b/dwarves.h
>>> @@ -90,6 +90,7 @@ struct conf_load {
>>> */
>>> struct conf_fprintf {
>>> const char *prefix;
>>> + const char *name_prefix;
>>> const char *suffix;
>>> int32_t type_spacing;
>>> int32_t name_spacing;
>>> diff --git a/pahole.c b/pahole.c
>>> index 42ba110..e0a1438 100644
>>> --- a/pahole.c
>>> +++ b/pahole.c
>>> @@ -2882,6 +2882,33 @@ out_btf:
>>>
>>> bool include_decls = find_pointers_in_structs != 0 || stats_formatter == nr_methods_formatter;
>>> struct prototype *prototype, *n;
>>> + static type_id_t class_id;
>>> +
>>> + uint32_t id;
>>> + struct tag *pos;
>>> + bool skip;
>>> + const char *prefix = conf_load->conf_fprintf->name_prefix;
>>> + const size_t prefix_len = prefix ? strlen(prefix) : 0;
>>> + cu__for_each_type(cu, id, pos) {
>>> + if (tag__is_type(pos)) {
>>> + const char *name = type__name(tag__type(pos));
>>> + if (name && prefix) {
>>> + skip = false;
>>> + list_for_each_entry_safe(prototype, n, &class_names, node) {
>>> + if (!strcmp(prototype->name, name)) {
>>> + skip = true;
>>> + break;
>>> + }
>>> + }
>>> + if (!skip) {
>>> + const size_t len = 1024 + prefix_len;
>>> + char *bf = malloc(len);
>>> + snprintf(bf, len, "%s%s", prefix, name);
>>> + tag__namespace(pos)->name = bf;
>>> + }
>>> + }
>>> + }
>>> + }
>>
>> I don't like this change in place mode, but I understand it is easier to
>> do it here instead of in all types fprintf routines, but perhaps its
>> better that way, I'll check how big it would be.
>
>I don't really like it either but the alternative is something like that:
>https://github.com/douglas-raillard-arm/pahole/commit/a3d4e224b2a0cb8196db0f8536bd77f976e364ca
>
>The worst is not the size of the patch, it's the inability to check that it's actually complete.
>Any spot where the prefix should be applied and where it is not will result in a broken header.
>This also stands for any future addition to dwarves_fprintf.c.
>
>One way to make the substitution safer is to completely ban direct access to the name and force
>to go through an accessor that would apply the prefix,
I like this, and we have tag__name(), I'm AFK now, will check if it fits.
Looking at your patch in te link you just provided
- Arnaldo
> but this leads to either memory management
>issue or inefficiency (as we would need to return copies so the caller can free it).
>
>>
>>>
>>> list_for_each_entry_safe(prototype, n, &class_names, node) {
>>>
>>> @@ -2891,8 +2918,6 @@ out_btf:
>>> prototype->type_enum_resolved = type__find_type_enum(tag__type(prototype->class), cu, prototype->type_enum) == 0;
>>> continue;
>>> }
>>> -
>>> - static type_id_t class_id;
>>> struct tag *class = cu__find_type_by_name(cu, prototype->name, include_decls, &class_id);
>>>
>>> // couldn't find that class name in this CU, continue to the next one.
>>> --
>>> 2.25.1
>>
>
