[haiku-commits] r39646 - in haiku/trunk: headers/private/kernel src/system/kernel
- From: ingo_weinhold@xxxxxx
- To: haiku-commits@xxxxxxxxxxxxx
- Date: Fri, 26 Nov 2010 14:32:25 +0100 (CET)
Author: bonefish
Date: 2010-11-26 14:32:24 +0100 (Fri, 26 Nov 2010)
New Revision: 39646
Changeset: http://dev.haiku-os.org/changeset/39646
Modified:
haiku/trunk/headers/private/kernel/elf_priv.h
haiku/trunk/src/system/kernel/elf.cpp
Log:
* elf_find_symbol(): Skip undefined symbols and symbols with the wrong binding.
* Implemented missing handling of symbolically linked images and of weak
symbols.
Modified: haiku/trunk/headers/private/kernel/elf_priv.h
===================================================================
--- haiku/trunk/headers/private/kernel/elf_priv.h 2010-11-26 13:24:10 UTC
(rev 39645)
+++ haiku/trunk/headers/private/kernel/elf_priv.h 2010-11-26 13:32:24 UTC
(rev 39646)
@@ -34,6 +34,8 @@
addr_t dynamic_section; // pointer to the
dynamic section
struct elf_linked_image *linked_images;
+ bool symbolic;
+
struct Elf32_Ehdr *elf_header;
// pointer to symbol participation data structures
Modified: haiku/trunk/src/system/kernel/elf.cpp
===================================================================
--- haiku/trunk/src/system/kernel/elf.cpp 2010-11-26 13:24:10 UTC (rev
39645)
+++ haiku/trunk/src/system/kernel/elf.cpp 2010-11-26 13:32:24 UTC (rev
39646)
@@ -19,6 +19,8 @@
#include <stdio.h>
#include <ctype.h>
+#include <algorithm>
+
#include <AutoDeleter.h>
#include <boot/kernel_args.h>
#include <debug.h>
@@ -603,8 +605,14 @@
for (uint32 i = HASHBUCKETS(image)[hash]; i != STN_UNDEF;
i = HASHCHAINS(image)[i]) {
Elf32_Sym* symbol = &image->syms[i];
- if (strcmp(SYMNAME(image, symbol), name) != 0)
+
+ // consider only symbols with the right name and binding
+ if (symbol->st_shndx == SHN_UNDEF
+ || ((ELF32_ST_BIND(symbol->st_info) != STB_GLOBAL)
+ && (ELF32_ST_BIND(symbol->st_info) != STB_WEAK))
+ || strcmp(SYMNAME(image, symbol), name) != 0) {
continue;
+ }
// check the version
@@ -767,6 +775,16 @@
case DT_VERNEEDNUM:
image->num_needed_versions = d[i].d_un.d_val;
break;
+ case DT_SYMBOLIC:
+ image->symbolic = true;
+ break;
+ case DT_FLAGS:
+ {
+ uint32 flags = d[i].d_un.d_val;
+ if ((flags & DF_SYMBOLIC) != 0)
+ image->symbolic = true;
+ break;
+ }
default:
continue;
@@ -979,7 +997,13 @@
return B_OK;
}
- // Non-local symbols we try to resolve to the kernel image first.
+ // Non-local symbols we try to resolve to the kernel image first. Unless
+ // the image is linked symbolically, then vice versa.
+ elf_image_info* firstImage = sharedImage;
+ elf_image_info* secondImage = image;
+ if (image->symbolic)
+ std::swap(firstImage, secondImage);
+
const char *symbolName = SYMNAME(image, symbol);
// get the version info
@@ -992,13 +1016,23 @@
}
// find the symbol
- elf_image_info* foundImage = sharedImage;
- struct Elf32_Sym* foundSymbol = elf_find_symbol(sharedImage, symbolName,
+ elf_image_info* foundImage = firstImage;
+ struct Elf32_Sym* foundSymbol = elf_find_symbol(firstImage, symbolName,
versionInfo, false);
- if (foundSymbol == NULL) {
- // not found yet, try to resolve in the requesting image
- foundImage = image;
- foundSymbol = elf_find_symbol(image, symbolName, versionInfo,
false);
+ if (foundSymbol == NULL
+ || ELF32_ST_BIND(foundSymbol->st_info) == STB_WEAK) {
+ // Not found or found a weak definition -- try to resolve in
the other
+ // image.
+ Elf32_Sym* secondSymbol = elf_find_symbol(secondImage,
symbolName,
+ versionInfo, false);
+ // If we found a symbol -- take it in case we didn't have a
symbol
+ // before or the new symbol is not weak.
+ if (secondSymbol != NULL
+ && (foundSymbol == NULL
+ || ELF32_ST_BIND(secondSymbol->st_info) !=
STB_WEAK)) {
+ foundImage = secondImage;
+ foundSymbol = secondSymbol;
+ }
}
if (foundSymbol == NULL) {
@@ -1015,18 +1049,14 @@
// make sure they're the same type
if (ELF32_ST_TYPE(symbol->st_info) !=
ELF32_ST_TYPE(foundSymbol->st_info)) {
- dprintf("elf_resolve_symbol: found symbol '%s' in shared image "
- "but wrong type\n", symbolName);
+ dprintf("elf_resolve_symbol: found symbol '%s' in image '%s' "
+ "(requested by image '%s') but wrong type (%d vs.
%d)\n",
+ symbolName, foundImage->name, image->name,
+ ELF32_ST_TYPE(foundSymbol->st_info),
+ ELF32_ST_TYPE(symbol->st_info));
return B_MISSING_SYMBOL;
}
- if (ELF32_ST_BIND(foundSymbol->st_info) != STB_GLOBAL
- && ELF32_ST_BIND(foundSymbol->st_info) != STB_WEAK) {
- TRACE(("elf_resolve_symbol: found symbol '%s' but not
exported\n",
- symbolName));
- return B_MISSING_SYMBOL;
- }
-
*_symbolAddress = foundSymbol->st_value + foundImage->text_region.delta;
return B_OK;
}
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- » [haiku-commits] r39646 - in haiku/trunk: headers/private/kernel src/system/kernel - ingo_weinhold
