[RFC,v8,10/20] Abstract the loaded-DSO search code into a private helper function
Commit Message
---
elf/dl-load.c | 38 ++++++++++++++++++++++++++++++++++++++
sysdeps/generic/ldsodefs.h | 4 ++++
2 files changed, 42 insertions(+)
Comments
On 09/02/2021 14:18, Vivek Das Mohapatra via Libc-alpha wrote:
> ---
> elf/dl-load.c | 38 ++++++++++++++++++++++++++++++++++++++
> sysdeps/generic/ldsodefs.h | 4 ++++
> 2 files changed, 42 insertions(+)
>
> diff --git a/elf/dl-load.c b/elf/dl-load.c
> index 3c5f667717..2a01ab7ad2 100644
> --- a/elf/dl-load.c
> +++ b/elf/dl-load.c
> @@ -2038,6 +2038,44 @@ _dl_find_proxy (Lmid_t nsid, const char *name)
> return NULL;
> }
>
> +/* search for a shared object in a given namespace. */
Maybe capitalize the 'search'?
> +struct link_map *
> +_dl_find_dso (const char *name, Lmid_t nsid)
> +{
> + struct link_map *l;
> +
> + for (l = GL(dl_ns)[nsid]._ns_loaded; l; l = l->l_next)
> + {
> + /* If the requested name matches the soname of a loaded object,
> + use that object. Elide this check for names that have not
> + yet been opened. */
> + if (__glibc_unlikely ((l->l_faked | l->l_removed) != 0))
> + continue;
> + if (!_dl_name_match_p (name, l))
> + {
> + const char *soname;
> +
> + if (__glibc_likely (l->l_soname_added)
> + || l->l_info[DT_SONAME] == NULL)
> + continue;
> +
> + soname = ((const char *) D_PTR (l, l_info[DT_STRTAB])
> + + l->l_info[DT_SONAME]->d_un.d_val);
> + if (strcmp (name, soname) != 0)
> + continue;
> +
> + /* We have a match on a new name -- cache it. */
> + add_name_to_object (l, soname);
> + l->l_soname_added = 1;
> + }
> +
> + /* We have a match. */
> + return l;
> + }
> +
> + return NULL;
> +}
> +
> /* Map in the shared object file NAME. */
>
> struct link_map *
Ok,
> diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h
> index f58b4ac49f..d0b9a22779 100644
> --- a/sysdeps/generic/ldsodefs.h
> +++ b/sysdeps/generic/ldsodefs.h
> @@ -1242,6 +1242,10 @@ extern void _dl_show_scope (struct link_map *new, int from)
> extern struct link_map *_dl_find_dso_for_object (const ElfW(Addr) addr);
> rtld_hidden_proto (_dl_find_dso_for_object)
>
> +extern struct link_map *_dl_find_dso (const char *name, Lmid_t nsid);
> +rtld_hidden_proto (_dl_find_dso)
> +
> +
> /* Initialization which is normally done by the dynamic linker. */
> extern void _dl_non_dynamic_init (void)
> attribute_hidden;
>
Ok.
@@ -2038,6 +2038,44 @@ _dl_find_proxy (Lmid_t nsid, const char *name)
return NULL;
}
+/* search for a shared object in a given namespace. */
+struct link_map *
+_dl_find_dso (const char *name, Lmid_t nsid)
+{
+ struct link_map *l;
+
+ for (l = GL(dl_ns)[nsid]._ns_loaded; l; l = l->l_next)
+ {
+ /* If the requested name matches the soname of a loaded object,
+ use that object. Elide this check for names that have not
+ yet been opened. */
+ if (__glibc_unlikely ((l->l_faked | l->l_removed) != 0))
+ continue;
+ if (!_dl_name_match_p (name, l))
+ {
+ const char *soname;
+
+ if (__glibc_likely (l->l_soname_added)
+ || l->l_info[DT_SONAME] == NULL)
+ continue;
+
+ soname = ((const char *) D_PTR (l, l_info[DT_STRTAB])
+ + l->l_info[DT_SONAME]->d_un.d_val);
+ if (strcmp (name, soname) != 0)
+ continue;
+
+ /* We have a match on a new name -- cache it. */
+ add_name_to_object (l, soname);
+ l->l_soname_added = 1;
+ }
+
+ /* We have a match. */
+ return l;
+ }
+
+ return NULL;
+}
+
/* Map in the shared object file NAME. */
struct link_map *
@@ -1242,6 +1242,10 @@ extern void _dl_show_scope (struct link_map *new, int from)
extern struct link_map *_dl_find_dso_for_object (const ElfW(Addr) addr);
rtld_hidden_proto (_dl_find_dso_for_object)
+extern struct link_map *_dl_find_dso (const char *name, Lmid_t nsid);
+rtld_hidden_proto (_dl_find_dso)
+
+
/* Initialization which is normally done by the dynamic linker. */
extern void _dl_non_dynamic_init (void)
attribute_hidden;