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From: "Vivek Das Mohapatra" <vivek@collabora.com>
To: libc-alpha@sourceware.org
Subject: [RFC][PATCH v11 2/7] Abstract loaded-DSO search code into a helper function
Date: Wed,  9 Jun 2021 18:16:13 +0100	[thread overview]
Message-ID: <20210609171618.20674-3-vivek@collabora.com> (raw)
In-Reply-To: <20210609171618.20674-1-vivek@collabora.com>

---
 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 918ec7546c..579ec92b9b 100644
--- a/elf/dl-load.c
+++ b/elf/dl-load.c
@@ -2027,6 +2027,44 @@ open_path (const char *name, size_t namelen, int mode,
   return -1;
 }
 
+/* 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 != NULL; 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 *
diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h
index 176394de4d..44e7097712 100644
--- a/sysdeps/generic/ldsodefs.h
+++ b/sysdeps/generic/ldsodefs.h
@@ -1287,6 +1287,10 @@ 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;
-- 
2.20.1


  parent reply	other threads:[~2021-06-09 17:16 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-09 17:16 [RFC][PATCH v11 0/7] Implementation of RTLD_SHARED for dlmopen Vivek Das Mohapatra
2021-06-09 17:16 ` [RFC][PATCH v11 1/7] Define a new dynamic section tag - DT_GNU_FLAGS_1 (bug 22745) Vivek Das Mohapatra
2021-06-09 17:16 ` Vivek Das Mohapatra [this message]
2021-06-09 17:16 ` [RFC][PATCH v11 3/7] Use the new DSO finder helper function Vivek Das Mohapatra
2021-06-09 17:16 ` [RFC][PATCH v11 4/7] Add DT_GNU_FLAGS_1/DF_GNU_1_UNIQUE to glibc DSOs (bug 22745) Vivek Das Mohapatra
2021-06-09 17:16 ` [RFC][PATCH v11 5/7] Implement dlmopen RTLD_SHARED flag " Vivek Das Mohapatra
2021-06-09 17:16 ` [RFC][PATCH v11 6/7] Add dlmopen / RTLD_SHARED tests Vivek Das Mohapatra
2021-06-09 17:16 ` [RFC][PATCH v11 7/7] Restore separate libc loading for the TLS/namespace storage test Vivek Das Mohapatra
2021-06-09 18:29 ` [RFC][PATCH v11 0/7] Implementation of RTLD_SHARED for dlmopen Florian Weimer
2021-06-09 22:50   ` Vivek Das Mohapatra
2021-06-16 13:08     ` [External] : " Alfonso Alfonso Peterssen
2021-06-20 23:18       ` Vivek Das Mohapatra

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