[OE-core] [PATCH 1/6] eglibc: relocatable SDK changes

[Laurentiu Palcu]

Modifying the dynamic loader path in all binaries by the SDK installer
would not be possible because we cannot know in advance the SDK target
location. Hence, the PT_INTERP section size has been set to 4096 (which
is the maximum path lengh in Linux).

Also, for the dynamic loader SYSDIRS and ld.so.cache paths, special
4096 bytes sections were allocated so that we can easily parse the ELF
binary at install time and modify the paths.

Signed-off-by: Laurentiu Palcu <laurentiu.palcu at intel.com>
---
 .../eglibc/eglibc-2.15/relocatable_sdk.patch       |   70 ++++++++++++++++++++
 meta/recipes-core/eglibc/eglibc_2.15.bb            |    6 +-
 2 files changed, 74 insertions(+), 2 deletions(-)
 create mode 100644 meta/recipes-core/eglibc/eglibc-2.15/relocatable_sdk.patch

diff --git a/meta/recipes-core/eglibc/eglibc-2.15/relocatable_sdk.patch b/meta/recipes-core/eglibc/eglibc-2.15/relocatable_sdk.patch
new file mode 100644
index 0000000..6c6f601
--- /dev/null
+++ b/meta/recipes-core/eglibc/eglibc-2.15/relocatable_sdk.patch
@@ -0,0 +1,70 @@
+Index: libc/elf/interp.c
+===================================================================
+--- libc.orig/elf/interp.c
++++ libc/elf/interp.c
+@@ -17,5 +17,5 @@
+    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+    02111-1307 USA.  */
+ 
+-const char __invoke_dynamic_linker__[] __attribute__ ((section (".interp")))
++const char __invoke_dynamic_linker__[4096] __attribute__ ((section (".interp")))
+   = RUNTIME_LINKER;
+Index: libc/elf/dl-load.c
+===================================================================
+--- libc.orig/elf/dl-load.c
++++ libc/elf/dl-load.c
+@@ -145,8 +145,8 @@ static size_t max_capstrlen attribute_re
+ /* Get the generated information about the trusted directories.  */
+ #include "trusted-dirs.h"
+ 
+-static const char system_dirs[] = SYSTEM_DIRS;
+-static const size_t system_dirs_len[] =
++static const char system_dirs[4096] __attribute__ ((section (".sysdirs"))) = SYSTEM_DIRS;
++volatile static const size_t system_dirs_len[] __attribute__ ((section (".sysdirslen"))) =
+ {
+   SYSTEM_DIRS_LEN
+ };
+Index: libc/elf/dl-cache.c
+===================================================================
+--- libc.orig/elf/dl-cache.c
++++ libc/elf/dl-cache.c
+@@ -134,6 +134,10 @@ do									      \
+ while (0)
+ 
+ 
++const char LD_SO_CACHE[4096] __attribute__ ((section (".ldsocache"))) =
++		SYSCONFDIR "/ld.so.cache";
++
++
+ int
+ internal_function
+ _dl_cache_libcmp (const char *p1, const char *p2)
+Index: libc/elf/ldconfig.c
+===================================================================
+--- libc.orig/elf/ldconfig.c
++++ libc/elf/ldconfig.c
+@@ -167,6 +167,9 @@ static struct argp argp =
+   options, parse_opt, NULL, doc, NULL, more_help, NULL
+ };
+ 
++
++extern const char LD_SO_CACHE[4096] __attribute__ ((section (".ldsocache")));
++
+ /* Check if string corresponds to an important hardware capability or
+    a platform.  */
+ static int
+Index: libc/sysdeps/generic/dl-cache.h
+===================================================================
+--- libc.orig/sysdeps/generic/dl-cache.h
++++ libc/sysdeps/generic/dl-cache.h
+@@ -28,10 +28,6 @@
+   ((flags) == 1 || (flags) == _DL_CACHE_DEFAULT_ID)
+ #endif
+ 
+-#ifndef LD_SO_CACHE
+-# define LD_SO_CACHE SYSCONFDIR "/ld.so.cache"
+-#endif
+-
+ #ifndef add_system_dir
+ # define add_system_dir(dir) add_dir (dir)
+ #endif
diff --git a/meta/recipes-core/eglibc/eglibc_2.15.bb b/meta/recipes-core/eglibc/eglibc_2.15.bb
index d9cb048..69db5c9 100644
--- a/meta/recipes-core/eglibc/eglibc_2.15.bb
+++ b/meta/recipes-core/eglibc/eglibc_2.15.bb
@@ -3,7 +3,7 @@ require eglibc.inc
 SRCREV = "19294"
 
 DEPENDS += "gperf-native"
-PR = "r12"
+PR = "r13"
 PR_append = "+svnr${SRCPV}"
 
 EGLIBC_BRANCH="eglibc-2_15"
@@ -33,7 +33,9 @@ LIC_FILES_CHKSUM = "file://LICENSES;md5=98a1128c4b58120182cbea3b1752d8b9 \
       file://posix/rxspencer/COPYRIGHT;md5=dc5485bb394a13b2332ec1c785f5d83a \
       file://COPYING.LIB;md5=bbb461211a33b134d42ed5ee802b37ff "
 
-SRC_URI_append_virtclass-nativesdk = " file://ld-search-order.patch"
+SRC_URI_append_virtclass-nativesdk = " file://ld-search-order.patch \
+            file://relocatable_sdk.patch \
+            "
 S = "${WORKDIR}/${EGLIBC_BRANCH}/libc"
 B = "${WORKDIR}/build-${TARGET_SYS}"
 
-- 
1.7.9.5