* Moved most code of the heavy elf.cpp into several smaller source files.

* Some style cleanup.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30808 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/system/runtime_loader/Jamfile

@@ -65,16 +65,26 @@ SEARCH on [ FGristFiles kernel_vsprintf.c ]
 SEARCH on [ FGristFiles KMessage.cpp ]
 	= [ FDirName $(HAIKU_TOP) src system kernel messaging ] ;
 
-Objects
-	runtime_loader.cpp
+
+local sources =
+	add_ons.cpp
 	elf.cpp
+	elf_haiku_version.cpp
+	elf_load_image.cpp
+	elf_symbol_lookup.cpp
+	elf_versioning.cpp
+	errors.cpp
 	export.cpp
 	heap.cpp
+	images.cpp
+	runtime_loader.cpp
 	utility.cpp
 ;
 
+Objects $(sources) ;
+
 Ld runtime_loader :
-	[ FGristFiles runtime_loader.o elf.o export.o heap.o utility.o ]
+	[ FGristFiles $(sources:S=$(SUFOBJ)) ]
 	libruntime_loader.a
 	libruntime_loader_$(TARGET_ARCH).a
 	$(TARGET_STATIC_LIBSUPC++)

src/system/runtime_loader/add_ons.cpp

@@ -0,0 +1,159 @@
+/*
+ * Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+
+#include "add_ons.h"
+
+#include <util/kernel_cpp.h>
+
+#include "runtime_loader_private.h"
+
+
+typedef DoublyLinkedList<RuntimeLoaderAddOn> AddOnList;
+
+
+static status_t register_defined_symbol_patcher(struct image_t* image,
+	runtime_loader_symbol_patcher* _patcher, void* cookie);
+static void unregister_defined_symbol_patcher(struct image_t* image,
+	runtime_loader_symbol_patcher* _patcher, void* cookie);
+static status_t register_undefined_symbol_patcher(struct image_t* image,
+	runtime_loader_symbol_patcher* _patcher, void* cookie);
+static void unregister_undefined_symbol_patcher(struct image_t* image,
+	runtime_loader_symbol_patcher* _patcher, void* cookie);
+
+
+static AddOnList sAddOns;
+
+static runtime_loader_add_on_export sRuntimeLoaderAddOnExport = {
+	register_defined_symbol_patcher,
+	unregister_defined_symbol_patcher,
+	register_undefined_symbol_patcher,
+	unregister_undefined_symbol_patcher
+};
+
+
+// #pragma mark - add-on support functions
+
+
+static status_t
+register_defined_symbol_patcher(struct image_t* image,
+	runtime_loader_symbol_patcher* _patcher, void* cookie)
+{
+	RuntimeLoaderSymbolPatcher* patcher
+		= new(mynothrow) RuntimeLoaderSymbolPatcher(_patcher, cookie);
+	if (patcher == NULL)
+		return B_NO_MEMORY;
+
+	patcher->next = image->defined_symbol_patchers;
+	image->defined_symbol_patchers = patcher;
+
+	return B_OK;
+}
+
+
+static void
+unregister_defined_symbol_patcher(struct image_t* image,
+	runtime_loader_symbol_patcher* _patcher, void* cookie)
+{
+	RuntimeLoaderSymbolPatcher** patcher = &image->defined_symbol_patchers;
+	while (*patcher != NULL) {
+		if ((*patcher)->patcher == _patcher && (*patcher)->cookie == cookie) {
+			RuntimeLoaderSymbolPatcher* toDelete = *patcher;
+			*patcher = (*patcher)->next;
+			delete toDelete;
+			return;
+		}
+		patcher = &(*patcher)->next;
+	}
+}
+
+
+static status_t
+register_undefined_symbol_patcher(struct image_t* image,
+	runtime_loader_symbol_patcher* _patcher, void* cookie)
+{
+	RuntimeLoaderSymbolPatcher* patcher
+		= new(mynothrow) RuntimeLoaderSymbolPatcher(_patcher, cookie);
+	if (patcher == NULL)
+		return B_NO_MEMORY;
+
+	patcher->next = image->undefined_symbol_patchers;
+	image->undefined_symbol_patchers = patcher;
+
+	return B_OK;
+}
+
+
+static void
+unregister_undefined_symbol_patcher(struct image_t* image,
+	runtime_loader_symbol_patcher* _patcher, void* cookie)
+{
+	RuntimeLoaderSymbolPatcher** patcher = &image->undefined_symbol_patchers;
+	while (*patcher != NULL) {
+		if ((*patcher)->patcher == _patcher && (*patcher)->cookie == cookie) {
+			RuntimeLoaderSymbolPatcher* toDelete = *patcher;
+			*patcher = (*patcher)->next;
+			delete toDelete;
+			return;
+		}
+		patcher = &(*patcher)->next;
+	}
+}
+
+
+// #pragma mark -
+
+
+void
+init_add_ons()
+{
+	// invoke static constructors
+	new(&sAddOns) AddOnList;
+}
+
+
+status_t
+add_add_on(image_t* image, runtime_loader_add_on* addOnStruct)
+{
+	RuntimeLoaderAddOn* addOn = new(mynothrow) RuntimeLoaderAddOn(image,
+		addOnStruct);
+	if (addOn == NULL)
+		return B_NO_MEMORY;
+
+	sAddOns.Add(addOn);
+	addOnStruct->init(&gRuntimeLoader, &sRuntimeLoaderAddOnExport);
+
+	return B_OK;
+}
+
+
+void
+image_event(image_t* image, uint32 event)
+{
+	AddOnList::Iterator it = sAddOns.GetIterator();
+	while (RuntimeLoaderAddOn* addOn = it.Next()) {
+		void (*function)(image_t* image) = NULL;
+
+		switch (event) {
+			case IMAGE_EVENT_LOADED:
+				function = addOn->addOn->image_loaded;
+				break;
+			case IMAGE_EVENT_RELOCATED:
+				function = addOn->addOn->image_relocated;
+				break;
+			case IMAGE_EVENT_INITIALIZED:
+				function = addOn->addOn->image_initialized;
+				break;
+			case IMAGE_EVENT_UNINITIALIZING:
+				function = addOn->addOn->image_uninitializing;
+				break;
+			case IMAGE_EVENT_UNLOADING:
+				function = addOn->addOn->image_unloading;
+				break;
+		}
+
+		if (function != NULL)
+			function(image);
+	}
+}

src/system/runtime_loader/add_ons.h

@@ -0,0 +1,59 @@
+/*
+ * Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef ADD_ONS_H
+#define ADD_ONS_H
+
+#include <OS.h>
+
+#include <util/DoublyLinkedList.h>
+
+#include <runtime_loader.h>
+
+
+// image events
+enum {
+	IMAGE_EVENT_LOADED,
+	IMAGE_EVENT_RELOCATED,
+	IMAGE_EVENT_INITIALIZED,
+	IMAGE_EVENT_UNINITIALIZING,
+	IMAGE_EVENT_UNLOADING
+};
+
+
+struct RuntimeLoaderAddOn
+		: public DoublyLinkedListLinkImpl<RuntimeLoaderAddOn> {
+	image_t*				image;
+	runtime_loader_add_on*	addOn;
+
+	RuntimeLoaderAddOn(image_t* image, runtime_loader_add_on* addOn)
+		:
+		image(image),
+		addOn(addOn)
+	{
+	}
+};
+
+
+struct RuntimeLoaderSymbolPatcher {
+	RuntimeLoaderSymbolPatcher*		next;
+	runtime_loader_symbol_patcher*	patcher;
+	void*							cookie;
+
+	RuntimeLoaderSymbolPatcher(runtime_loader_symbol_patcher* patcher,
+			void* cookie)
+		:
+		patcher(patcher),
+		cookie(cookie)
+	{
+	}
+};
+
+
+void		init_add_ons();
+status_t	add_add_on(image_t* image, runtime_loader_add_on* addOnStruct);
+void		image_event(image_t* image, uint32 event);
+
+
+#endif	// ADD_ONS_H

src/system/runtime_loader/elf_haiku_version.cpp

@@ -0,0 +1,234 @@
+/*
+ * Copyright 2008-2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+
+#include "elf_haiku_version.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <image_defs.h>
+#include <syscalls.h>
+
+#include "elf_symbol_lookup.h"
+
+
+// interim Haiku API versions
+#define HAIKU_VERSION_PRE_GLUE_CODE		0x00000010
+
+
+static bool
+analyze_object_gcc_version(int fd, image_t* image, Elf32_Ehdr& eheader,
+	int32 sheaderSize, char* buffer, size_t bufferSize)
+{
+	if (sheaderSize > (int)bufferSize) {
+		FATAL("Cannot handle section headers bigger than %lu\n", bufferSize);
+		return false;
+	}
+
+	// read section headers
+	ssize_t length = _kern_read(fd, eheader.e_shoff, buffer, sheaderSize);
+	if (length != sheaderSize) {
+		FATAL("Could not read section headers: %s\n", strerror(length));
+		return false;
+	}
+
+	// load the string section
+	Elf32_Shdr* sectionHeader
+		= (Elf32_Shdr*)(buffer + eheader.e_shstrndx * eheader.e_shentsize);
+
+	if (sheaderSize + sectionHeader->sh_size > bufferSize) {
+		FATAL("Buffer not big enough for section string section\n");
+		return false;
+	}
+
+	char* sectionStrings = buffer + bufferSize - sectionHeader->sh_size;
+	length = _kern_read(fd, sectionHeader->sh_offset, sectionStrings,
+		sectionHeader->sh_size);
+	if (length != (int)sectionHeader->sh_size) {
+		FATAL("Could not read section string section: %s\n", strerror(length));
+		return false;
+	}
+
+	// find the .comment section
+	off_t commentOffset = 0;
+	size_t commentSize = 0;
+	for (uint32 i = 0; i < eheader.e_shnum; i++) {
+		sectionHeader = (Elf32_Shdr*)(buffer + i * eheader.e_shentsize);
+		const char* sectionName = sectionStrings + sectionHeader->sh_name;
+		if (sectionHeader->sh_name != 0
+			&& strcmp(sectionName, ".comment") == 0) {
+			commentOffset = sectionHeader->sh_offset;
+			commentSize = sectionHeader->sh_size;
+			break;
+		}
+	}
+
+	if (commentSize == 0) {
+		FATAL("Could not find .comment section\n");
+		return false;
+	}
+
+	// read a part of the comment section
+	if (commentSize > 512)
+		commentSize = 512;
+
+	length = _kern_read(fd, commentOffset, buffer, commentSize);
+	if (length != (int)commentSize) {
+		FATAL("Could not read .comment section: %s\n", strerror(length));
+		return false;
+	}
+
+	// the common prefix of the strings in the .comment section
+	static const char* kGCCVersionPrefix = "GCC: (GNU) ";
+	size_t gccVersionPrefixLen = strlen(kGCCVersionPrefix);
+
+	size_t index = 0;
+	int gccMajor = 0;
+	int gccMiddle = 0;
+	int gccMinor = 0;
+	bool isHaiku = true;
+
+	// Read up to 10 comments. The first three or four are usually from the
+	// glue code.
+	for (int i = 0; i < 10; i++) {
+		// skip '\0'
+		while (index < commentSize && buffer[index] == '\0')
+			index++;
+		char* stringStart = buffer + index;
+
+		// find string end
+		while (index < commentSize && buffer[index] != '\0')
+			index++;
+
+		// ignore the entry at the end of the buffer
+		if (index == commentSize)
+			break;
+
+		// We have to analyze string like these:
+		// GCC: (GNU) 2.9-beos-991026
+		// GCC: (GNU) 2.95.3-haiku-080322
+		// GCC: (GNU) 4.1.2
+
+		// skip the common prefix
+		if (strncmp(stringStart, kGCCVersionPrefix, gccVersionPrefixLen) != 0)
+			continue;
+
+		// the rest is the GCC version
+		char* gccVersion = stringStart + gccVersionPrefixLen;
+		char* gccPlatform = strchr(gccVersion, '-');
+		char* patchLevel = NULL;
+		if (gccPlatform != NULL) {
+			*gccPlatform = '\0';
+			gccPlatform++;
+			patchLevel = strchr(gccPlatform, '-');
+			if (patchLevel != NULL) {
+				*patchLevel = '\0';
+				patchLevel++;
+			}
+		}
+
+		// split the gcc version into major, middle, and minor
+		int version[3] = { 0, 0, 0 };
+
+		for (int k = 0; gccVersion != NULL && k < 3; k++) {
+			char* dot = strchr(gccVersion, '.');
+			if (dot) {
+				*dot = '\0';
+				dot++;
+			}
+			version[k] = atoi(gccVersion);
+			gccVersion = dot;
+		}
+
+		// got any version?
+		if (version[0] == 0)
+			continue;
+
+		// Select the gcc version with the smallest major, but the greatest
+		// middle/minor. This should usually ignore the glue code version as
+		// well as cases where e.g. in a gcc 2 program a single C file has
+		// been compiled with gcc 4.
+		if (gccMajor == 0 || gccMajor > version[0]
+		 	|| (gccMajor == version[0]
+				&& (gccMiddle < version[1]
+					|| (gccMiddle == version[1] && gccMinor < version[2])))) {
+			gccMajor = version[0];
+			gccMiddle = version[1];
+			gccMinor = version[2];
+		}
+
+		if (gccMajor == 2 && gccPlatform != NULL
+			&& strcmp(gccPlatform, "haiku")) {
+			isHaiku = false;
+		}
+	}
+
+	if (gccMajor == 0)
+		return false;
+
+	if (gccMajor == 2) {
+		if (gccMiddle < 95)
+			image->abi = B_HAIKU_ABI_GCC_2_ANCIENT;
+		else if (isHaiku)
+			image->abi = B_HAIKU_ABI_GCC_2_HAIKU;
+		else
+			image->abi = B_HAIKU_ABI_GCC_2_BEOS;
+	} else
+		image->abi = gccMajor << 16;
+
+	return true;
+}
+
+
+void
+analyze_image_haiku_version_and_abi(int fd, image_t* image, Elf32_Ehdr& eheader,
+	int32 sheaderSize, char* buffer, size_t bufferSize)
+{
+	// Haiku API version
+	struct Elf32_Sym* symbol = find_symbol(image,
+		SymbolLookupInfo(B_SHARED_OBJECT_HAIKU_VERSION_VARIABLE_NAME,
+			B_SYMBOL_TYPE_DATA));
+	if (symbol != NULL && symbol->st_shndx != SHN_UNDEF
+		&& symbol->st_value > 0
+		&& ELF32_ST_TYPE(symbol->st_info) == STT_OBJECT
+		&& symbol->st_size >= sizeof(uint32)) {
+		image->api_version
+			= *(uint32*)(symbol->st_value + image->regions[0].delta);
+	} else
+		image->api_version = 0;
+
+	// Haiku ABI
+	symbol = find_symbol(image,
+		SymbolLookupInfo(B_SHARED_OBJECT_HAIKU_ABI_VARIABLE_NAME,
+			B_SYMBOL_TYPE_DATA));
+	if (symbol != NULL && symbol->st_shndx != SHN_UNDEF
+		&& symbol->st_value > 0
+		&& ELF32_ST_TYPE(symbol->st_info) == STT_OBJECT
+		&& symbol->st_size >= sizeof(uint32)) {
+		image->abi = *(uint32*)(symbol->st_value + image->regions[0].delta);
+	} else
+		image->abi = 0;
+
+	if (image->abi == 0) {
+		// No ABI version in the shared object, i.e. it has been built before
+		// that was introduced in Haiku. We have to try and analyze the gcc
+		// version.
+		if (!analyze_object_gcc_version(fd, image, eheader, sheaderSize,
+				buffer, bufferSize)) {
+			FATAL("Failed to get gcc version for %s\n", image->path);
+				// not really fatal, actually
+
+			// assume ancient BeOS
+			image->abi = B_HAIKU_ABI_GCC_2_ANCIENT;
+		}
+	}
+
+	// guess the API version, if we couldn't figure it out yet
+	if (image->api_version == 0) {
+		image->api_version = image->abi > B_HAIKU_ABI_GCC_2_BEOS
+			? HAIKU_VERSION_PRE_GLUE_CODE : B_HAIKU_VERSION_BEOS;
+	}
+}

src/system/runtime_loader/elf_haiku_version.h

@@ -0,0 +1,16 @@
+/*
+ * Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef ELF_HAIKU_VERSION_H
+#define ELF_HAIKU_VERSION_H
+
+#include "runtime_loader_private.h"
+
+
+void	analyze_image_haiku_version_and_abi(int fd, image_t* image,
+			Elf32_Ehdr& eheader, int32 sheaderSize, char* buffer,
+			size_t bufferSize);
+
+
+#endif	// ELF_HAIKU_VERSION_H

src/system/runtime_loader/elf_load_image.cpp

@@ -0,0 +1,547 @@
+/*
+ * Copyright 2008-2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Copyright 2003-2008, Axel Dörfler, axeld@pinc-software.de.
+ * Distributed under the terms of the MIT License.
+ *
+ * Copyright 2002, Manuel J. Petit. All rights reserved.
+ * Copyright 2001, Travis Geiselbrecht. All rights reserved.
+ * Distributed under the terms of the NewOS License.
+ */
+
+#include "elf_load_image.h"
+
+#include <stdio.h>
+#include <string.h>
+
+#include <syscalls.h>
+
+#include "add_ons.h"
+#include "elf_haiku_version.h"
+#include "elf_symbol_lookup.h"
+#include "elf_versioning.h"
+#include "images.h"
+#include "runtime_loader_private.h"
+
+
+static const char* sSearchPathSubDir = NULL;
+
+
+static const char*
+get_program_path()
+{
+	return gProgramImage != NULL ? gProgramImage->path : NULL;
+}
+
+
+static int32
+count_regions(char const* buff, int phnum, int phentsize)
+{
+	struct Elf32_Phdr* pheaders;
+	int32 count = 0;
+	int i;
+
+	for (i = 0; i < phnum; i++) {
+		pheaders = (struct Elf32_Phdr*)(buff + i * phentsize);
+
+		switch (pheaders->p_type) {
+			case PT_NULL:
+				// NOP header
+				break;
+			case PT_LOAD:
+				count += 1;
+				if (pheaders->p_memsz != pheaders->p_filesz) {
+					addr_t A = TO_PAGE_SIZE(pheaders->p_vaddr
+						+ pheaders->p_memsz);
+					addr_t B = TO_PAGE_SIZE(pheaders->p_vaddr
+						+ pheaders->p_filesz);
+
+					if (A != B)
+						count += 1;
+				}
+				break;
+			case PT_DYNAMIC:
+				// will be handled at some other place
+				break;
+			case PT_INTERP:
+				// should check here for appropiate interpreter
+				break;
+			case PT_NOTE:
+				// unsupported
+				break;
+			case PT_SHLIB:
+				// undefined semantics
+				break;
+			case PT_PHDR:
+				// we don't use it
+				break;
+			case PT_STACK:
+				// we don't use it
+				break;
+			default:
+				FATAL("unhandled pheader type in count 0x%lx\n",
+					pheaders->p_type);
+				return B_BAD_DATA;
+		}
+	}
+
+	return count;
+}
+
+
+static status_t
+parse_program_headers(image_t* image, char* buff, int phnum, int phentsize)
+{
+	struct Elf32_Phdr* pheader;
+	int regcount;
+	int i;
+
+	regcount = 0;
+	for (i = 0; i < phnum; i++) {
+		pheader = (struct Elf32_Phdr*)(buff + i * phentsize);
+
+		switch (pheader->p_type) {
+			case PT_NULL:
+				/* NOP header */
+				break;
+			case PT_LOAD:
+				if (pheader->p_memsz == pheader->p_filesz) {
+					/*
+					 * everything in one area
+					 */
+					image->regions[regcount].start = pheader->p_vaddr;
+					image->regions[regcount].size = pheader->p_memsz;
+					image->regions[regcount].vmstart
+						= PAGE_BASE(pheader->p_vaddr);
+					image->regions[regcount].vmsize
+						= TO_PAGE_SIZE(pheader->p_memsz
+							+ PAGE_OFFSET(pheader->p_vaddr));
+					image->regions[regcount].fdstart = pheader->p_offset;
+					image->regions[regcount].fdsize = pheader->p_filesz;
+					image->regions[regcount].delta = 0;
+					image->regions[regcount].flags = 0;
+					if (pheader->p_flags & PF_WRITE) {
+						// this is a writable segment
+						image->regions[regcount].flags |= RFLAG_RW;
+					}
+				} else {
+					/*
+					 * may require splitting
+					 */
+					addr_t A = TO_PAGE_SIZE(pheader->p_vaddr
+						+ pheader->p_memsz);
+					addr_t B = TO_PAGE_SIZE(pheader->p_vaddr
+						+ pheader->p_filesz);
+
+					image->regions[regcount].start = pheader->p_vaddr;
+					image->regions[regcount].size = pheader->p_filesz;
+					image->regions[regcount].vmstart
+						= PAGE_BASE(pheader->p_vaddr);
+					image->regions[regcount].vmsize
+						= TO_PAGE_SIZE(pheader->p_filesz
+							+ PAGE_OFFSET(pheader->p_vaddr));
+					image->regions[regcount].fdstart = pheader->p_offset;
+					image->regions[regcount].fdsize = pheader->p_filesz;
+					image->regions[regcount].delta = 0;
+					image->regions[regcount].flags = 0;
+					if (pheader->p_flags & PF_WRITE) {
+						// this is a writable segment
+						image->regions[regcount].flags |= RFLAG_RW;
+					}
+
+					if (A != B) {
+						/*
+						 * yeah, it requires splitting
+						 */
+						regcount += 1;
+						image->regions[regcount].start = pheader->p_vaddr;
+						image->regions[regcount].size
+							= pheader->p_memsz - pheader->p_filesz;
+						image->regions[regcount].vmstart
+							= image->regions[regcount-1].vmstart
+								+ image->regions[regcount-1].vmsize;
+						image->regions[regcount].vmsize
+							= TO_PAGE_SIZE(pheader->p_memsz
+									+ PAGE_OFFSET(pheader->p_vaddr))
+								- image->regions[regcount-1].vmsize;
+						image->regions[regcount].fdstart = 0;
+						image->regions[regcount].fdsize = 0;
+						image->regions[regcount].delta = 0;
+						image->regions[regcount].flags = RFLAG_ANON;
+						if (pheader->p_flags & PF_WRITE) {
+							// this is a writable segment
+							image->regions[regcount].flags |= RFLAG_RW;
+						}
+					}
+				}
+				regcount += 1;
+				break;
+			case PT_DYNAMIC:
+				image->dynamic_ptr = pheader->p_vaddr;
+				break;
+			case PT_INTERP:
+				// should check here for appropiate interpreter
+				break;
+			case PT_NOTE:
+				// unsupported
+				break;
+			case PT_SHLIB:
+				// undefined semantics
+				break;
+			case PT_PHDR:
+				// we don't use it
+				break;
+			case PT_STACK:
+				// we don't use it
+				break;
+			default:
+				FATAL("unhandled pheader type in parse 0x%lx\n",
+					pheader->p_type);
+				return B_BAD_DATA;
+		}
+	}
+
+	return B_OK;
+}
+
+
+static bool
+assert_dynamic_loadable(image_t* image)
+{
+	uint32 i;
+
+	if (!image->dynamic_ptr)
+		return true;
+
+	for (i = 0; i < image->num_regions; i++) {
+		if (image->dynamic_ptr >= image->regions[i].start
+			&& image->dynamic_ptr
+				< image->regions[i].start + image->regions[i].size) {
+			return true;
+		}
+	}
+
+	return false;
+}
+
+
+static bool
+parse_dynamic_segment(image_t* image)
+{
+	struct Elf32_Dyn* d;
+	int i;
+	int sonameOffset = -1;
+
+	image->symhash = 0;
+	image->syms = 0;
+	image->strtab = 0;
+
+	d = (struct Elf32_Dyn*)image->dynamic_ptr;
+	if (!d)
+		return true;
+
+	for (i = 0; d[i].d_tag != DT_NULL; i++) {
+		switch (d[i].d_tag) {
+			case DT_NEEDED:
+				image->num_needed += 1;
+				break;
+			case DT_HASH:
+				image->symhash
+					= (uint32*)(d[i].d_un.d_ptr + image->regions[0].delta);
+				break;
+			case DT_STRTAB:
+				image->strtab
+					= (char*)(d[i].d_un.d_ptr + image->regions[0].delta);
+				break;
+			case DT_SYMTAB:
+				image->syms = (struct Elf32_Sym*)
+					(d[i].d_un.d_ptr + image->regions[0].delta);
+				break;
+			case DT_REL:
+				image->rel = (struct Elf32_Rel*)
+					(d[i].d_un.d_ptr + image->regions[0].delta);
+				break;
+			case DT_RELSZ:
+				image->rel_len = d[i].d_un.d_val;
+				break;
+			case DT_RELA:
+				image->rela = (struct Elf32_Rela*)
+					(d[i].d_un.d_ptr + image->regions[0].delta);
+				break;
+			case DT_RELASZ:
+				image->rela_len = d[i].d_un.d_val;
+				break;
+			// TK: procedure linkage table
+			case DT_JMPREL:
+				image->pltrel = (struct Elf32_Rel*)
+					(d[i].d_un.d_ptr + image->regions[0].delta);
+				break;
+			case DT_PLTRELSZ:
+				image->pltrel_len = d[i].d_un.d_val;
+				break;
+			case DT_INIT:
+				image->init_routine
+					= (d[i].d_un.d_ptr + image->regions[0].delta);
+				break;
+			case DT_FINI:
+				image->term_routine
+					= (d[i].d_un.d_ptr + image->regions[0].delta);
+				break;
+			case DT_SONAME:
+				sonameOffset = d[i].d_un.d_val;
+				break;
+			case DT_VERSYM:
+				image->symbol_versions = (Elf32_Versym*)
+					(d[i].d_un.d_ptr + image->regions[0].delta);
+				break;
+			case DT_VERDEF:
+				image->version_definitions = (Elf32_Verdef*)
+					(d[i].d_un.d_ptr + image->regions[0].delta);
+				break;
+			case DT_VERDEFNUM:
+				image->num_version_definitions = d[i].d_un.d_val;
+				break;
+			case DT_VERNEED:
+				image->needed_versions = (Elf32_Verneed*)
+					(d[i].d_un.d_ptr + image->regions[0].delta);
+				break;
+			case DT_VERNEEDNUM:
+				image->num_needed_versions = d[i].d_un.d_val;
+				break;
+			default:
+				continue;
+		}
+	}
+
+	// lets make sure we found all the required sections
+	if (!image->symhash || !image->syms || !image->strtab)
+		return false;
+
+	if (sonameOffset >= 0)
+		strlcpy(image->name, STRING(image, sonameOffset), sizeof(image->name));
+
+	return true;
+}
+
+
+// #pragma mark -
+
+
+status_t
+parse_elf_header(struct Elf32_Ehdr* eheader, int32* _pheaderSize,
+	int32* _sheaderSize)
+{
+	if (memcmp(eheader->e_ident, ELF_MAGIC, 4) != 0)
+		return B_NOT_AN_EXECUTABLE;
+
+	if (eheader->e_ident[4] != ELFCLASS32)
+		return B_NOT_AN_EXECUTABLE;
+
+	if (eheader->e_phoff == 0)
+		return B_NOT_AN_EXECUTABLE;
+
+	if (eheader->e_phentsize < sizeof(struct Elf32_Phdr))
+		return B_NOT_AN_EXECUTABLE;
+
+	*_pheaderSize = eheader->e_phentsize * eheader->e_phnum;
+	*_sheaderSize = eheader->e_shentsize * eheader->e_shnum;
+
+	if (*_pheaderSize <= 0 || *_sheaderSize <= 0)
+		return B_NOT_AN_EXECUTABLE;
+
+	return B_OK;
+}
+
+
+status_t
+load_image(char const* name, image_type type, const char* rpath,
+	image_t** _image)
+{
+	int32 pheaderSize, sheaderSize;
+	char path[PATH_MAX];
+	ssize_t length;
+	char pheaderBuffer[4096];
+	int32 numRegions;
+	image_t* found;
+	image_t* image;
+	status_t status;
+	int fd;
+
+	struct Elf32_Ehdr eheader;
+
+	// Have we already loaded that image? Don't check for add-ons -- we always
+	// reload them.
+	if (type != B_ADD_ON_IMAGE) {
+		found = find_loaded_image_by_name(name, APP_OR_LIBRARY_TYPE);
+
+		if (found == NULL && type != B_APP_IMAGE) {
+			// Special case for add-ons that link against the application
+			// executable, with the executable not having a soname set.
+			if (const char* lastSlash = strrchr(name, '/')) {
+				if (strcmp(gProgramImage->name, lastSlash + 1) == 0)
+					found = gProgramImage;
+			}
+		}
+
+		if (found) {
+			atomic_add(&found->ref_count, 1);
+			*_image = found;
+			KTRACE("rld: load_container(\"%s\", type: %d, rpath: \"%s\") "
+				"already loaded", name, type, rpath);
+			return B_OK;
+		}
+	}
+
+	KTRACE("rld: load_container(\"%s\", type: %d, rpath: \"%s\")", name, type,
+		rpath);
+
+	strlcpy(path, name, sizeof(path));
+
+	// find and open the file
+	fd = open_executable(path, type, rpath, get_program_path(),
+		sSearchPathSubDir);
+	if (fd < 0) {
+		FATAL("cannot open file %s\n", name);
+		KTRACE("rld: load_container(\"%s\"): failed to open file", name);
+		return fd;
+	}
+
+	// normalize the image path
+	status = _kern_normalize_path(path, true, path);
+	if (status != B_OK)
+		goto err1;
+
+	// Test again if this image has been registered already - this time,
+	// we can check the full path, not just its name as noted.
+	// You could end up loading an image twice with symbolic links, else.
+	if (type != B_ADD_ON_IMAGE) {
+		found = find_loaded_image_by_name(path, APP_OR_LIBRARY_TYPE);
+		if (found) {
+			atomic_add(&found->ref_count, 1);
+			*_image = found;
+			_kern_close(fd);
+			KTRACE("rld: load_container(\"%s\"): already loaded after all",
+				name);
+			return B_OK;
+		}
+	}
+
+	length = _kern_read(fd, 0, &eheader, sizeof(eheader));
+	if (length != sizeof(eheader)) {
+		status = B_NOT_AN_EXECUTABLE;
+		FATAL("troubles reading ELF header\n");
+		goto err1;
+	}
+
+	status = parse_elf_header(&eheader, &pheaderSize, &sheaderSize);
+	if (status < B_OK) {
+		FATAL("incorrect ELF header\n");
+		goto err1;
+	}
+
+	// ToDo: what to do about this restriction??
+	if (pheaderSize > (int)sizeof(pheaderBuffer)) {
+		FATAL("Cannot handle program headers bigger than %lu\n",
+			sizeof(pheaderBuffer));
+		status = B_UNSUPPORTED;
+		goto err1;
+	}
+
+	length = _kern_read(fd, eheader.e_phoff, pheaderBuffer, pheaderSize);
+	if (length != pheaderSize) {
+		FATAL("Could not read program headers: %s\n", strerror(length));
+		status = B_BAD_DATA;
+		goto err1;
+	}
+
+	numRegions = count_regions(pheaderBuffer, eheader.e_phnum,
+		eheader.e_phentsize);
+	if (numRegions <= 0) {
+		FATAL("Troubles parsing Program headers, numRegions = %ld\n", numRegions);
+		status = B_BAD_DATA;
+		goto err1;
+	}
+
+	image = create_image(name, path, numRegions);
+	if (image == NULL) {
+		FATAL("Failed to allocate image_t object\n");
+		status = B_NO_MEMORY;
+		goto err1;
+	}
+
+	status = parse_program_headers(image, pheaderBuffer, eheader.e_phnum,
+		eheader.e_phentsize);
+	if (status < B_OK)
+		goto err2;
+
+	if (!assert_dynamic_loadable(image)) {
+		FATAL("Dynamic segment must be loadable (implementation restriction)\n");
+		status = B_UNSUPPORTED;
+		goto err2;
+	}
+
+	status = map_image(fd, path, image, type == B_APP_IMAGE);
+	if (status < B_OK) {
+		FATAL("Could not map image: %s\n", strerror(status));
+		status = B_ERROR;
+		goto err2;
+	}
+
+	if (!parse_dynamic_segment(image)) {
+		FATAL("Troubles handling dynamic section\n");
+		status = B_BAD_DATA;
+		goto err3;
+	}
+
+	if (eheader.e_entry != 0)
+		image->entry_point = eheader.e_entry + image->regions[0].delta;
+
+	analyze_image_haiku_version_and_abi(fd, image, eheader, sheaderSize,
+		pheaderBuffer, sizeof(pheaderBuffer));
+
+	// If this is the executable image, we init the search path
+	// subdir, if the compiler version doesn't match ours.
+	if (type == B_APP_IMAGE) {
+		#if __GNUC__ == 2
+			if ((image->abi & B_HAIKU_ABI_MAJOR) == B_HAIKU_ABI_GCC_4)
+				sSearchPathSubDir = "gcc4";
+		#elif __GNUC__ == 4
+			if ((image->abi & B_HAIKU_ABI_MAJOR) == B_HAIKU_ABI_GCC_2)
+				sSearchPathSubDir = "gcc2";
+		#endif
+	}
+
+	// init gcc version dependent image flags
+	// symbol resolution strategy
+	if (image->abi == B_HAIKU_ABI_GCC_2_ANCIENT)
+		image->find_undefined_symbol = find_undefined_symbol_beos;
+
+	// init version infos
+	status = init_image_version_infos(image);
+
+	image->type = type;
+	register_image(image, fd, path);
+	image_event(image, IMAGE_EVENT_LOADED);
+
+	_kern_close(fd);
+
+	enqueue_loaded_image(image);
+
+	*_image = image;
+
+	KTRACE("rld: load_container(\"%s\"): done: id: %ld (ABI: %#lx)", name,
+		image->id, image->abi);
+
+	return B_OK;
+
+err3:
+	unmap_image(image);
+err2:
+	delete_image_struct(image);
+err1:
+	_kern_close(fd);
+
+	KTRACE("rld: load_container(\"%s\"): failed: %s", name,
+		strerror(status));
+
+	return status;
+}

src/system/runtime_loader/elf_load_image.h

@@ -0,0 +1,17 @@
+/*
+ * Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef ELF_LOAD_IMAGE_H
+#define ELF_LOAD_IMAGE_H
+
+#include "runtime_loader_private.h"
+
+
+status_t	parse_elf_header(struct Elf32_Ehdr* eheader, int32* _pheaderSize,
+				int32* _sheaderSize);
+status_t	load_image(char const* name, image_type type, const char* rpath,
+				image_t** _image);
+
+
+#endif	// ELF_LOAD_IMAGE_H

src/system/runtime_loader/elf_symbol_lookup.cpp

@@ -0,0 +1,472 @@
+/*
+ * Copyright 2008-2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Copyright 2003-2008, Axel Dörfler, axeld@pinc-software.de.
+ * Distributed under the terms of the MIT License.
+ *
+ * Copyright 2002, Manuel J. Petit. All rights reserved.
+ * Copyright 2001, Travis Geiselbrecht. All rights reserved.
+ * Distributed under the terms of the NewOS License.
+ */
+
+#include "elf_symbol_lookup.h"
+
+#include <dlfcn.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "add_ons.h"
+#include "errors.h"
+#include "images.h"
+#include "runtime_loader_private.h"
+
+
+static bool
+equals_image_name(image_t* image, const char* name)
+{
+	const char* lastSlash = strrchr(name, '/');
+	return strcmp(image->name, lastSlash != NULL ? lastSlash + 1 : name) == 0;
+}
+
+
+/*!	This function is called when we run BeOS images on Haiku.
+	It allows us to redirect functions to ensure compatibility.
+*/
+static const char*
+beos_compatibility_map_symbol(const char* symbolName)
+{
+	struct symbol_mapping {
+		const char* from;
+		const char* to;
+	};
+	static const struct symbol_mapping kMappings[] = {
+		// TODO: Improve this, and also use it for libnet.so compatibility!
+		// Allow an image to provide a function that will be invoked for every
+		// (transitively) depending image. The function can return a table to
+		// remap symbols (probably better address to address). All the tables
+		// for a single image would be combined into a hash table and an
+		// undefined symbol patcher using this hash table would be added.
+		{"fstat", "__be_fstat"},
+		{"lstat", "__be_lstat"},
+		{"stat", "__be_stat"},
+	};
+	const uint32 kMappingCount = sizeof(kMappings) / sizeof(kMappings[0]);
+
+	for (uint32 i = 0; i < kMappingCount; i++) {
+		if (!strcmp(symbolName, kMappings[i].from))
+			return kMappings[i].to;
+	}
+
+	return symbolName;
+}
+
+
+// #pragma mark -
+
+
+uint32
+elf_hash(const char* _name)
+{
+	const uint8* name = (const uint8*)_name;
+
+	uint32 hash = 0;
+	uint32 temp;
+
+	while (*name) {
+		hash = (hash << 4) + *name++;
+		if ((temp = hash & 0xf0000000)) {
+			hash ^= temp >> 24;
+		}
+		hash &= ~temp;
+	}
+	return hash;
+}
+
+
+void
+patch_defined_symbol(image_t* image, const char* name, void** symbol,
+	int32* type)
+{
+	RuntimeLoaderSymbolPatcher* patcher = image->defined_symbol_patchers;
+	while (patcher != NULL && *symbol != 0) {
+		image_t* inImage = image;
+		patcher->patcher(patcher->cookie, NULL, image, name, &inImage,
+			symbol, type);
+		patcher = patcher->next;
+	}
+}
+
+
+void
+patch_undefined_symbol(image_t* rootImage, image_t* image, const char* name,
+	image_t** foundInImage, void** symbol, int32* type)
+{
+	if (*foundInImage != NULL)
+		patch_defined_symbol(*foundInImage, name, symbol, type);
+
+	RuntimeLoaderSymbolPatcher* patcher = image->undefined_symbol_patchers;
+	while (patcher != NULL) {
+		patcher->patcher(patcher->cookie, rootImage, image, name, foundInImage,
+			symbol, type);
+		patcher = patcher->next;
+	}
+}
+
+
+Elf32_Sym*
+find_symbol(image_t* image, const SymbolLookupInfo& lookupInfo)
+{
+	if (image->dynamic_ptr == 0)
+		return NULL;
+
+	Elf32_Sym* versionedSymbol = NULL;
+	uint32 versionedSymbolCount = 0;
+
+	uint32 bucket = lookupInfo.hash % HASHTABSIZE(image);
+
+	for (uint32 i = HASHBUCKETS(image)[bucket]; i != STN_UNDEF;
+			i = HASHCHAINS(image)[i]) {
+		Elf32_Sym* symbol = &image->syms[i];
+
+		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), lookupInfo.name)) {
+
+			// check if the type matches
+			uint32 type = ELF32_ST_TYPE(symbol->st_info);
+			if ((lookupInfo.type == B_SYMBOL_TYPE_TEXT && type != STT_FUNC)
+				|| (lookupInfo.type == B_SYMBOL_TYPE_DATA
+					&& type != STT_OBJECT)) {
+				continue;
+			}
+
+			// check the version
+
+			// Handle the simple cases -- the image doesn't have version
+			// information -- first.
+			if (image->symbol_versions == NULL) {
+				if (lookupInfo.version == NULL) {
+					// No specific symbol version was requested either, so the
+					// symbol is just fine.
+					return symbol;
+				}
+
+				// A specific version is requested. If it's the dependency
+				// referred to by the requested version, it's apparently an
+				// older version of the dependency and we're not happy.
+				if (equals_image_name(image, lookupInfo.version->file_name)) {
+					// TODO: That should actually be kind of fatal!
+					return NULL;
+				}
+
+				// This is some other image. We accept the symbol.
+				return symbol;
+			}
+
+			// The image has version information. Let's see what we've got.
+			uint32 versionID = image->symbol_versions[i];
+			uint32 versionIndex = VER_NDX(versionID);
+			elf_version_info& version = image->versions[versionIndex];
+
+			// skip local versions
+			if (versionIndex == VER_NDX_LOCAL)
+				continue;
+
+			if (lookupInfo.version != NULL) {
+				// a specific version is requested
+
+				// compare the versions
+				if (version.hash == lookupInfo.version->hash
+					&& strcmp(version.name, lookupInfo.version->name) == 0) {
+					// versions match
+					return symbol;
+				}
+
+				// The versions don't match. We're still fine with the
+				// base version, if it is public and we're not looking for
+				// the default version.
+				if ((versionID & VER_NDX_FLAG_HIDDEN) == 0
+					&& versionIndex == VER_NDX_GLOBAL
+					&& (lookupInfo.flags & LOOKUP_FLAG_DEFAULT_VERSION)
+						== 0) {
+					// TODO: Revise the default version case! That's how
+					// FreeBSD implements it, but glibc doesn't handle it
+					// specially.
+					return symbol;
+				}
+			} else {
+				// No specific version requested, but the image has version
+				// information. This can happen in either of these cases:
+				//
+				// * The dependent object was linked against an older version
+				//   of the now versioned dependency.
+				// * The symbol is looked up via find_image_symbol() or dlsym().
+				//
+				// In the first case we return the base version of the symbol
+				// (VER_NDX_GLOBAL or VER_NDX_INITIAL), or, if that doesn't
+				// exist, the unique, non-hidden versioned symbol.
+				//
+				// In the second case we want to return the public default
+				// version of the symbol. The handling is pretty similar to the
+				// first case, with the exception that we treat VER_NDX_INITIAL
+				// as regular version.
+
+				// VER_NDX_GLOBAL is always good, VER_NDX_INITIAL is fine, if
+				// we don't look for the default version.
+				if (versionIndex == VER_NDX_GLOBAL
+					|| ((lookupInfo.flags & LOOKUP_FLAG_DEFAULT_VERSION) == 0
+						&& versionIndex == VER_NDX_INITIAL)) {
+					return symbol;
+				}
+
+				// If not hidden, remember the version -- we'll return it, if
+				// it is the only one.
+				if ((versionID & VER_NDX_FLAG_HIDDEN) == 0) {
+					versionedSymbolCount++;
+					versionedSymbol = symbol;
+				}
+			}
+		}
+	}
+
+	return versionedSymbolCount == 1 ? versionedSymbol : NULL;
+}
+
+
+status_t
+find_symbol(image_t* image, const SymbolLookupInfo& lookupInfo,
+	void **_location)
+{
+	// get the symbol in the image
+	Elf32_Sym* symbol = find_symbol(image, lookupInfo);
+	if (symbol == NULL)
+		return B_ENTRY_NOT_FOUND;
+
+	void* location = (void*)(symbol->st_value + image->regions[0].delta);
+	int32 symbolType = lookupInfo.type;
+	patch_defined_symbol(image, lookupInfo.name, &location, &symbolType);
+
+	if (_location != NULL)
+		*_location = location;
+
+	return B_OK;
+}
+
+
+status_t
+find_symbol_breadth_first(image_t* image, const SymbolLookupInfo& lookupInfo,
+	image_t** _foundInImage, void** _location)
+{
+	image_t* queue[count_loaded_images()];
+	uint32 count = 0;
+	uint32 index = 0;
+	queue[count++] = image;
+	image->flags |= RFLAG_VISITED;
+
+	bool found = false;
+	while (index < count) {
+		// pop next image
+		image = queue[index++];
+
+		if (find_symbol(image, lookupInfo, _location) == B_OK) {
+			found = true;
+			break;
+		}
+
+		// push needed images
+		for (uint32 i = 0; i < image->num_needed; i++) {
+			image_t* needed = image->needed[i];
+			if ((needed->flags & RFLAG_VISITED) == 0) {
+				queue[count++] = needed;
+				needed->flags |= RFLAG_VISITED;
+			}
+		}
+	}
+
+	// clear visited flags
+	for (uint32 i = 0; i < count; i++)
+		queue[i]->flags &= ~RFLAG_VISITED;
+
+	return found ? B_OK : B_ENTRY_NOT_FOUND;
+}
+
+
+Elf32_Sym*
+find_undefined_symbol_beos(image_t* rootImage, image_t* image,
+	const SymbolLookupInfo& lookupInfo, image_t** foundInImage)
+{
+	// BeOS style symbol resolution: It is sufficient to check the direct
+	// dependencies. The linker would have complained, if the symbol wasn't
+	// there.
+	for (uint32 i = 0; i < image->num_needed; i++) {
+		if (image->needed[i]->dynamic_ptr) {
+			Elf32_Sym *symbol = find_symbol(image->needed[i],
+				lookupInfo);
+			if (symbol) {
+				*foundInImage = image->needed[i];
+				return symbol;
+			}
+		}
+	}
+
+	return NULL;
+}
+
+
+Elf32_Sym*
+find_undefined_symbol_global(image_t* rootImage, image_t* image,
+	const SymbolLookupInfo& lookupInfo, image_t** foundInImage)
+{
+	// Global load order symbol resolution: All loaded images are searched for
+	// the symbol in the order they have been loaded. We skip add-on images and
+	// RTLD_LOCAL images though.
+	image_t* otherImage = get_loaded_images().head;
+	while (otherImage != NULL) {
+		if (otherImage == rootImage
+			|| (otherImage->type != B_ADD_ON_IMAGE
+				&& (otherImage->flags
+					& (RTLD_GLOBAL | RFLAG_USE_FOR_RESOLVING)) != 0)) {
+			Elf32_Sym *symbol = find_symbol(otherImage, lookupInfo);
+			if (symbol) {
+				*foundInImage = otherImage;
+				return symbol;
+			}
+		}
+		otherImage = otherImage->next;
+	}
+
+	return NULL;
+}
+
+
+Elf32_Sym*
+find_undefined_symbol_add_on(image_t* rootImage, image_t* image,
+	const SymbolLookupInfo& lookupInfo, image_t** foundInImage)
+{
+// TODO: How do we want to implement this one? Using global scope resolution
+// might be undesired as it is now, since libraries could refer to symbols in
+// the add-on, which would result in add-on symbols implicitely becoming used
+// outside of the add-on. So the options would be to use the global scope but
+// skip the add-on, or to do breadth-first resolution in the add-on dependency
+// scope, also skipping the add-on itself. BeOS style resolution is safe, too,
+// but we miss out features like undefined symbols and preloading.
+	return find_undefined_symbol_beos(rootImage, image, lookupInfo,
+		foundInImage);
+}
+
+
+int
+resolve_symbol(image_t* rootImage, image_t* image, struct Elf32_Sym* sym,
+	addr_t* symAddress)
+{
+	switch (sym->st_shndx) {
+		case SHN_UNDEF:
+		{
+			struct Elf32_Sym* sharedSym;
+			image_t* sharedImage;
+			const char* symName = SYMNAME(image, sym);
+
+			// patch the symbol name
+			if (image->abi < B_HAIKU_ABI_GCC_2_HAIKU) {
+				// The image has been compiled with a BeOS compiler. This means
+				// we'll have to redirect some functions for compatibility.
+				symName = beos_compatibility_map_symbol(symName);
+			}
+
+			// get the version info
+			const elf_version_info* versionInfo = NULL;
+			if (image->symbol_versions != NULL) {
+				uint32 index = sym - image->syms;
+				uint32 versionIndex = VER_NDX(image->symbol_versions[index]);
+				if (versionIndex >= VER_NDX_INITIAL)
+					versionInfo = image->versions + versionIndex;
+			}
+
+			int32 type = B_SYMBOL_TYPE_ANY;
+			if (ELF32_ST_TYPE(sym->st_info) == STT_FUNC)
+				type = B_SYMBOL_TYPE_TEXT;
+			else if (ELF32_ST_TYPE(sym->st_info) == STT_OBJECT)
+				type = B_SYMBOL_TYPE_DATA;
+
+			// it's undefined, must be outside this image, try the other images
+			sharedSym = rootImage->find_undefined_symbol(rootImage, image,
+				SymbolLookupInfo(symName, type, versionInfo), &sharedImage);
+			void* location = NULL;
+
+			enum {
+				ERROR_NO_SYMBOL,
+				ERROR_WRONG_TYPE,
+				ERROR_NOT_EXPORTED,
+				ERROR_UNPATCHED
+			};
+			uint32 lookupError = ERROR_UNPATCHED;
+
+			if (sharedSym == NULL) {
+				// symbol not found at all
+				lookupError = ERROR_NO_SYMBOL;
+				sharedImage = NULL;
+			} else if (ELF32_ST_TYPE(sym->st_info) != STT_NOTYPE
+				&& ELF32_ST_TYPE(sym->st_info)
+					!= ELF32_ST_TYPE(sharedSym->st_info)) {
+				// symbol not of the requested type
+				lookupError = ERROR_WRONG_TYPE;
+				sharedImage = NULL;
+			} else if (ELF32_ST_BIND(sharedSym->st_info) != STB_GLOBAL
+				&& ELF32_ST_BIND(sharedSym->st_info) != STB_WEAK) {
+				// symbol not exported
+				lookupError = ERROR_NOT_EXPORTED;
+				sharedImage = NULL;
+			} else {
+				// symbol is fine, get its location
+				location = (void*)(sharedSym->st_value
+					+ sharedImage->regions[0].delta);
+			}
+
+			patch_undefined_symbol(rootImage, image, symName, &sharedImage,
+				&location, &type);
+
+			if (location == NULL) {
+				switch (lookupError) {
+					case ERROR_NO_SYMBOL:
+						FATAL("elf_resolve_symbol: could not resolve symbol "
+							"'%s'\n", symName);
+						break;
+					case ERROR_WRONG_TYPE:
+						FATAL("elf_resolve_symbol: found symbol '%s' in shared "
+							"image but wrong type\n", symName);
+						break;
+					case ERROR_NOT_EXPORTED:
+						FATAL("elf_resolve_symbol: found symbol '%s', but not "
+							"exported\n", symName);
+						break;
+					case ERROR_UNPATCHED:
+						FATAL("elf_resolve_symbol: found symbol '%s', but was "
+							"hidden by symbol patchers\n", symName);
+						break;
+				}
+
+				if (report_errors())
+					gErrorMessage.AddString("missing symbol", symName);
+
+				return B_MISSING_SYMBOL;
+			}
+
+			*symAddress = (addr_t)location;
+			return B_OK;
+		}
+
+		case SHN_ABS:
+			*symAddress = sym->st_value + image->regions[0].delta;
+			return B_NO_ERROR;
+
+		case SHN_COMMON:
+			// ToDo: finish this
+			FATAL("elf_resolve_symbol: COMMON symbol, finish me!\n");
+			return B_ERROR; //ERR_NOT_IMPLEMENTED_YET;
+
+		default:
+			// standard symbol
+			*symAddress = sym->st_value + image->regions[0].delta;
+			return B_NO_ERROR;
+	}
+}

src/system/runtime_loader/elf_symbol_lookup.h

@@ -0,0 +1,69 @@
+/*
+ * Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef ELF_SYMBOL_LOOKUP_H
+#define ELF_SYMBOL_LOOKUP_H
+
+#include <runtime_loader.h>
+
+
+// values for SymbolLookupInfo::flags
+#define LOOKUP_FLAG_DEFAULT_VERSION	0x01
+
+
+uint32 elf_hash(const char* name);
+
+
+struct SymbolLookupInfo {
+	const char*				name;
+	int32					type;
+	uint32					hash;
+	uint32					flags;
+	const elf_version_info*	version;
+
+	SymbolLookupInfo(const char* name, int32 type, uint32 hash,
+		const elf_version_info* version = NULL, uint32 flags = 0)
+		:
+		name(name),
+		type(type),
+		hash(hash),
+		flags(flags),
+		version(version)
+	{
+	}
+
+	SymbolLookupInfo(const char* name, int32 type,
+		const elf_version_info* version = NULL, uint32 flags = 0)
+		:
+		name(name),
+		type(type),
+		hash(elf_hash(name)),
+		flags(flags),
+		version(version)
+	{
+	}
+};
+
+
+void		patch_defined_symbol(image_t* image, const char* name,
+				void** symbol, int32* type);
+void		patch_undefined_symbol(image_t* rootImage, image_t* image,
+				const char* name, image_t** foundInImage, void** symbol,
+				int32* type);
+
+Elf32_Sym*	find_symbol(image_t* image, const SymbolLookupInfo& lookupInfo);
+status_t	find_symbol(image_t* image, const SymbolLookupInfo& lookupInfo,
+				void** _location);
+status_t	find_symbol_breadth_first(image_t* image,
+				const SymbolLookupInfo& lookupInfo, image_t** _foundInImage,
+				void** _location);
+Elf32_Sym*	find_undefined_symbol_beos(image_t* rootImage, image_t* image,
+				const SymbolLookupInfo& lookupInfo, image_t** foundInImage);
+Elf32_Sym*	find_undefined_symbol_global(image_t* rootImage, image_t* image,
+				const SymbolLookupInfo& lookupInfo, image_t** foundInImage);
+Elf32_Sym*	find_undefined_symbol_add_on(image_t* rootImage, image_t* image,
+				const SymbolLookupInfo& lookupInfo, image_t** foundInImage);
+
+
+#endif	// ELF_SYMBOL_LOOKUP_H

src/system/runtime_loader/elf_versioning.cpp

@@ -0,0 +1,203 @@
+/*
+ * Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+
+#include "elf_versioning.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "images.h"
+
+
+static status_t
+assert_defined_image_version(image_t* dependentImage, image_t* image,
+	const elf_version_info& neededVersion, bool weak)
+{
+	// If the image doesn't have version definitions, we print a warning and
+	// succeed. Weird, but that's how glibc does it. Not unlikely we'll fail
+	// later when resolving versioned symbols.
+	if (image->version_definitions == NULL) {
+		FATAL("%s: No version information available (required by %s)\n",
+			image->name, dependentImage->name);
+		return B_OK;
+	}
+
+	// iterate through the defined versions to find the given one
+	Elf32_Verdef* definition = image->version_definitions;
+	for (uint32 i = 0; i < image->num_version_definitions; i++) {
+		uint32 versionIndex = VER_NDX(definition->vd_ndx);
+		elf_version_info& info = image->versions[versionIndex];
+
+		if (neededVersion.hash == info.hash
+			&& strcmp(neededVersion.name, info.name) == 0) {
+			return B_OK;
+		}
+
+		definition = (Elf32_Verdef*)
+			((uint8*)definition + definition->vd_next);
+	}
+
+	// version not found -- fail, if not weak
+	if (!weak) {
+		FATAL("%s: version \"%s\" not found (required by %s)\n", image->name,
+			neededVersion.name, dependentImage->name);
+		return B_MISSING_SYMBOL;
+	}
+
+	return B_OK;
+}
+
+
+// #pragma mark -
+
+
+status_t
+init_image_version_infos(image_t* image)
+{
+	// First find out how many version infos we need -- i.e. get the greatest
+	// version index from the defined and needed versions (they use the same
+	// index namespace).
+	uint32 maxIndex = 0;
+
+	if (image->version_definitions != NULL) {
+		Elf32_Verdef* definition = image->version_definitions;
+		for (uint32 i = 0; i < image->num_version_definitions; i++) {
+			if (definition->vd_version != 1) {
+				FATAL("Unsupported version definition revision: %u\n",
+					definition->vd_version);
+				return B_BAD_VALUE;
+			}
+
+			uint32 versionIndex = VER_NDX(definition->vd_ndx);
+			if (versionIndex > maxIndex)
+				maxIndex = versionIndex;
+
+			definition = (Elf32_Verdef*)
+				((uint8*)definition	+ definition->vd_next);
+		}
+	}
+
+	if (image->needed_versions != NULL) {
+		Elf32_Verneed* needed = image->needed_versions;
+		for (uint32 i = 0; i < image->num_needed_versions; i++) {
+			if (needed->vn_version != 1) {
+				FATAL("Unsupported version needed revision: %u\n",
+					needed->vn_version);
+				return B_BAD_VALUE;
+			}
+
+			Elf32_Vernaux* vernaux
+				= (Elf32_Vernaux*)((uint8*)needed + needed->vn_aux);
+			for (uint32 k = 0; k < needed->vn_cnt; k++) {
+				uint32 versionIndex = VER_NDX(vernaux->vna_other);
+				if (versionIndex > maxIndex)
+					maxIndex = versionIndex;
+
+				vernaux = (Elf32_Vernaux*)((uint8*)vernaux + vernaux->vna_next);
+			}
+
+			needed = (Elf32_Verneed*)((uint8*)needed + needed->vn_next);
+		}
+	}
+
+	if (maxIndex == 0)
+		return B_OK;
+
+	// allocate the version infos
+	image->versions
+		= (elf_version_info*)malloc(sizeof(elf_version_info) * (maxIndex + 1));
+	if (image->versions == NULL) {
+		FATAL("Memory shortage in init_image_version_infos()");
+		return B_NO_MEMORY;
+	}
+	image->num_versions = maxIndex + 1;
+
+	// init the version infos
+
+	// version definitions
+	if (image->version_definitions != NULL) {
+		Elf32_Verdef* definition = image->version_definitions;
+		for (uint32 i = 0; i < image->num_version_definitions; i++) {
+			if (definition->vd_cnt > 0
+				&& (definition->vd_flags & VER_FLG_BASE) == 0) {
+				Elf32_Verdaux* verdaux
+					= (Elf32_Verdaux*)((uint8*)definition + definition->vd_aux);
+
+				uint32 versionIndex = VER_NDX(definition->vd_ndx);
+				elf_version_info& info = image->versions[versionIndex];
+				info.hash = definition->vd_hash;
+				info.name = STRING(image, verdaux->vda_name);
+			}
+
+			definition = (Elf32_Verdef*)
+				((uint8*)definition + definition->vd_next);
+		}
+	}
+
+	// needed versions
+	if (image->needed_versions != NULL) {
+		Elf32_Verneed* needed = image->needed_versions;
+		for (uint32 i = 0; i < image->num_needed_versions; i++) {
+			const char* fileName = STRING(image, needed->vn_file);
+
+			Elf32_Vernaux* vernaux
+				= (Elf32_Vernaux*)((uint8*)needed + needed->vn_aux);
+			for (uint32 k = 0; k < needed->vn_cnt; k++) {
+				uint32 versionIndex = VER_NDX(vernaux->vna_other);
+				elf_version_info& info = image->versions[versionIndex];
+				info.hash = vernaux->vna_hash;
+				info.name = STRING(image, vernaux->vna_name);
+				info.file_name = fileName;
+				info.hidden = (vernaux->vna_other & VER_NDX_FLAG_HIDDEN) != 0;
+
+				vernaux = (Elf32_Vernaux*)((uint8*)vernaux + vernaux->vna_next);
+			}
+
+			needed = (Elf32_Verneed*)((uint8*)needed + needed->vn_next);
+		}
+	}
+
+	return B_OK;
+}
+
+
+status_t
+check_needed_image_versions(image_t* image)
+{
+	if (image->needed_versions == NULL)
+		return B_OK;
+
+	Elf32_Verneed* needed = image->needed_versions;
+	for (uint32 i = 0; i < image->num_needed_versions; i++) {
+		const char* fileName = STRING(image, needed->vn_file);
+		image_t* dependency = find_loaded_image_by_name(fileName,
+			ALL_IMAGE_TYPES);
+		if (dependency == NULL) {
+			// This can't really happen, unless the object file is broken, since
+			// the file should also appear in DT_NEEDED.
+			FATAL("Version dependency \"%s\" not found", fileName);
+			return B_FILE_NOT_FOUND;
+		}
+
+		Elf32_Vernaux* vernaux
+			= (Elf32_Vernaux*)((uint8*)needed + needed->vn_aux);
+		for (uint32 k = 0; k < needed->vn_cnt; k++) {
+			uint32 versionIndex = VER_NDX(vernaux->vna_other);
+			elf_version_info& info = image->versions[versionIndex];
+
+			status_t error = assert_defined_image_version(image, dependency,
+				info, (vernaux->vna_flags & VER_FLG_WEAK) != 0);
+			if (error != B_OK)
+				return error;
+
+			vernaux = (Elf32_Vernaux*)((uint8*)vernaux + vernaux->vna_next);
+		}
+
+		needed = (Elf32_Verneed*)((uint8*)needed + needed->vn_next);
+	}
+
+	return B_OK;
+}

src/system/runtime_loader/elf_versioning.h

@@ -0,0 +1,15 @@
+/*
+ * Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef ELF_VERSIONING_H
+#define ELF_VERSIONING_H
+
+#include "runtime_loader_private.h"
+
+
+status_t	init_image_version_infos(image_t* image);
+status_t	check_needed_image_versions(image_t* image);
+
+
+#endif	// ELF_VERSIONING_H

src/system/runtime_loader/errors.cpp

@@ -0,0 +1,9 @@
+/*
+ * Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+
+#include "errors.h"
+
+
+KMessage gErrorMessage;

src/system/runtime_loader/errors.h

@@ -0,0 +1,23 @@
+/*
+ * Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef ERRORS_H
+#define ERRORS_H
+
+#include <util/KMessage.h>
+
+#include "runtime_loader_private.h"
+
+
+extern KMessage gErrorMessage;
+
+
+static inline bool
+report_errors()
+{
+	return gProgramArgs->error_port >= 0;
+}
+
+
+#endif	// ERRORS_H

src/system/runtime_loader/images.cpp

@@ -0,0 +1,541 @@
+/*
+ * Copyright 2008-2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Copyright 2003-2008, Axel Dörfler, axeld@pinc-software.de.
+ * Distributed under the terms of the MIT License.
+ *
+ * Copyright 2002, Manuel J. Petit. All rights reserved.
+ * Copyright 2001, Travis Geiselbrecht. All rights reserved.
+ * Distributed under the terms of the NewOS License.
+ */
+
+#include "images.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <syscalls.h>
+#include <vm_defs.h>
+
+#include "add_ons.h"
+#include "runtime_loader_private.h"
+
+
+#define RLD_PROGRAM_BASE 0x00200000
+	/* keep in sync with app ldscript */
+
+
+bool gInvalidImageIDs;
+
+static image_queue_t sLoadedImages = {0, 0};
+static image_queue_t sDisposableImages = {0, 0};
+static uint32 sLoadedImageCount = 0;
+
+
+//! Remaps the image ID of \a image after fork.
+static status_t
+update_image_id(image_t* image)
+{
+	int32 cookie = 0;
+	image_info info;
+	while (_kern_get_next_image_info(B_CURRENT_TEAM, &cookie, &info,
+			sizeof(image_info)) == B_OK) {
+		for (uint32 i = 0; i < image->num_regions; i++) {
+			if (image->regions[i].vmstart == (addr_t)info.text) {
+				image->id = info.id;
+				return B_OK;
+			}
+		}
+	}
+
+	FATAL("Could not update image ID %ld after fork()!\n", image->id);
+	return B_ENTRY_NOT_FOUND;
+}
+
+
+static void
+enqueue_image(image_queue_t* queue, image_t* image)
+{
+	image->next = NULL;
+
+	image->prev = queue->tail;
+	if (queue->tail)
+		queue->tail->next = image;
+
+	queue->tail = image;
+	if (!queue->head)
+		queue->head = image;
+}
+
+
+static void
+dequeue_image(image_queue_t* queue, image_t* image)
+{
+	if (image->next)
+		image->next->prev = image->prev;
+	else
+		queue->tail = image->prev;
+
+	if (image->prev)
+		image->prev->next = image->next;
+	else
+		queue->head = image->next;
+
+	image->prev = NULL;
+	image->next = NULL;
+}
+
+
+static image_t*
+find_image_in_queue(image_queue_t* queue, const char* name, bool isPath,
+	uint32 typeMask)
+{
+	for (image_t* image = queue->head; image; image = image->next) {
+		const char* imageName = isPath ? image->path : image->name;
+		int length = isPath ? sizeof(image->path) : sizeof(image->name);
+
+		if (!strncmp(imageName, name, length)
+			&& (typeMask & IMAGE_TYPE_TO_MASK(image->type)) != 0) {
+			return image;
+		}
+	}
+
+	return NULL;
+}
+
+
+static void
+update_image_flags_recursively(image_t* image, uint32 flagsToSet,
+	uint32 flagsToClear)
+{
+	image_t* queue[sLoadedImageCount];
+	uint32 count = 0;
+	uint32 index = 0;
+	queue[count++] = image;
+	image->flags |= RFLAG_VISITED;
+
+	while (index < count) {
+		// pop next image
+		image = queue[index++];
+
+		// push dependencies
+		for (uint32 i = 0; i < image->num_needed; i++) {
+			image_t* needed = image->needed[i];
+			if ((needed->flags & RFLAG_VISITED) == 0) {
+				queue[count++] = needed;
+				needed->flags |= RFLAG_VISITED;
+			}
+		}
+	}
+
+	// update flags
+	for (uint32 i = 0; i < count; i++) {
+		queue[i]->flags = (queue[i]->flags | flagsToSet)
+			& ~(flagsToClear | RFLAG_VISITED);
+	}
+}
+
+
+static uint32
+topological_sort(image_t* image, uint32 slot, image_t** initList,
+	uint32 sortFlag)
+{
+	uint32 i;
+
+	if (image->flags & sortFlag)
+		return slot;
+
+	image->flags |= sortFlag; /* make sure we don't visit this one */
+	for (i = 0; i < image->num_needed; i++)
+		slot = topological_sort(image->needed[i], slot, initList, sortFlag);
+
+	initList[slot] = image;
+	return slot + 1;
+}
+
+
+// #pragma mark -
+
+
+image_t*
+create_image(const char* name, const char* path, int regionCount)
+{
+	size_t allocSize = sizeof(image_t)
+		+ (regionCount - 1) * sizeof(elf_region_t);
+
+	image_t* image = (image_t*)malloc(allocSize);
+	if (image == NULL) {
+		FATAL("no memory for image %s\n", path);
+		return NULL;
+	}
+
+	memset(image, 0, allocSize);
+
+	strlcpy(image->path, path, sizeof(image->path));
+
+	// Make the last component of the supplied name the image name.
+	// If present, DT_SONAME will replace this name.
+	const char* lastSlash = strrchr(name, '/');
+	if (lastSlash != NULL)
+		strlcpy(image->name, lastSlash + 1, sizeof(image->name));
+	else
+		strlcpy(image->name, name, sizeof(image->name));
+
+	image->ref_count = 1;
+	image->num_regions = regionCount;
+
+	return image;
+}
+
+
+void
+delete_image_struct(image_t* image)
+{
+#ifdef DEBUG
+	size_t size = sizeof(image_t)
+		+ (image->num_regions - 1) * sizeof(elf_region_t);
+	memset(image->needed, 0xa5, sizeof(image->needed[0]) * image->num_needed);
+#endif
+	free(image->needed);
+	free(image->versions);
+
+	while (RuntimeLoaderSymbolPatcher* patcher
+			= image->defined_symbol_patchers) {
+		image->defined_symbol_patchers = patcher->next;
+		delete patcher;
+	}
+	while (RuntimeLoaderSymbolPatcher* patcher
+			= image->undefined_symbol_patchers) {
+		image->undefined_symbol_patchers = patcher->next;
+		delete patcher;
+	}
+
+#ifdef DEBUG
+	// overwrite images to make sure they aren't accidently reused anywhere
+	memset(image, 0xa5, size);
+#endif
+	free(image);
+}
+
+
+void
+delete_image(image_t* image)
+{
+	if (image == NULL)
+		return;
+
+	_kern_unregister_image(image->id);
+		// registered in load_container()
+
+	delete_image_struct(image);
+}
+
+
+void
+put_image(image_t* image)
+{
+	// If all references to the image are gone, add it to the disposable list
+	// and remove all dependencies
+
+	if (atomic_add(&image->ref_count, -1) == 1) {
+		size_t i;
+
+		dequeue_image(&sLoadedImages, image);
+		enqueue_image(&sDisposableImages, image);
+		sLoadedImageCount--;
+
+		for (i = 0; i < image->num_needed; i++)
+			put_image(image->needed[i]);
+	}
+}
+
+
+status_t
+map_image(int fd, char const* path, image_t* image, bool fixed)
+{
+	// cut the file name from the path as base name for the created areas
+	const char* baseName = strrchr(path, '/');
+	if (baseName != NULL)
+		baseName++;
+	else
+		baseName = path;
+
+	for (uint32 i = 0; i < image->num_regions; i++) {
+		char regionName[B_OS_NAME_LENGTH];
+		addr_t loadAddress;
+		uint32 addressSpecifier;
+
+		// for BeOS compatibility: if we load an old BeOS executable, we
+		// have to relocate it, if possible - we recognize it because the
+		// vmstart is set to 0 (hopefully always)
+		if (fixed && image->regions[i].vmstart == 0)
+			fixed = false;
+
+		snprintf(regionName, sizeof(regionName), "%s_seg%lu%s",
+			baseName, i, (image->regions[i].flags & RFLAG_RW) ? "rw" : "ro");
+
+		if (image->dynamic_ptr && !fixed) {
+			// relocatable image... we can afford to place wherever
+			if (i == 0) {
+				// but only the first segment gets a free ride
+				loadAddress = RLD_PROGRAM_BASE;
+				addressSpecifier = B_BASE_ADDRESS;
+			} else {
+				loadAddress = image->regions[i].vmstart
+					+ image->regions[i-1].delta;
+				addressSpecifier = B_EXACT_ADDRESS;
+			}
+		} else {
+			// not relocatable, put it where it asks or die trying
+			loadAddress = image->regions[i].vmstart;
+			addressSpecifier = B_EXACT_ADDRESS;
+		}
+
+		if (image->regions[i].flags & RFLAG_ANON) {
+			image->regions[i].id = _kern_create_area(regionName,
+				(void**)&loadAddress, addressSpecifier,
+				image->regions[i].vmsize, B_NO_LOCK,
+				B_READ_AREA | B_WRITE_AREA);
+
+			if (image->regions[i].id < 0)
+				return image->regions[i].id;
+
+			image->regions[i].delta = loadAddress - image->regions[i].vmstart;
+			image->regions[i].vmstart = loadAddress;
+		} else {
+			image->regions[i].id = _kern_map_file(regionName,
+				(void**)&loadAddress, addressSpecifier,
+				image->regions[i].vmsize, B_READ_AREA | B_WRITE_AREA,
+				REGION_PRIVATE_MAP, fd, PAGE_BASE(image->regions[i].fdstart));
+
+			if (image->regions[i].id < 0)
+				return image->regions[i].id;
+
+			TRACE(("\"%s\" at %p, 0x%lx bytes (%s)\n", path,
+				(void *)loadAddress, image->regions[i].vmsize,
+				image->regions[i].flags & RFLAG_RW ? "rw" : "read-only"));
+
+			image->regions[i].delta = loadAddress - image->regions[i].vmstart;
+			image->regions[i].vmstart = loadAddress;
+
+			// handle trailer bits in data segment
+			if (image->regions[i].flags & RFLAG_RW) {
+				addr_t startClearing;
+				addr_t toClear;
+
+				startClearing = image->regions[i].vmstart
+					+ PAGE_OFFSET(image->regions[i].start)
+					+ image->regions[i].size;
+				toClear = image->regions[i].vmsize
+					- PAGE_OFFSET(image->regions[i].start)
+					- image->regions[i].size;
+
+				TRACE(("cleared 0x%lx and the following 0x%lx bytes\n",
+					startClearing, toClear));
+				memset((void *)startClearing, 0, toClear);
+			}
+		}
+	}
+
+	if (image->dynamic_ptr)
+		image->dynamic_ptr += image->regions[0].delta;
+
+	return B_OK;
+}
+
+
+void
+unmap_image(image_t* image)
+{
+	for (uint32 i = 0; i < image->num_regions; i++) {
+		_kern_delete_area(image->regions[i].id);
+
+		image->regions[i].id = -1;
+	}
+}
+
+
+/*!	This function will change the protection of all read-only segments to really
+	be read-only.
+	The areas have to be read/write first, so that they can be relocated.
+*/
+void
+remap_images()
+{
+	for (image_t* image = sLoadedImages.head; image != NULL;
+			image = image->next) {
+		for (uint32 i = 0; i < image->num_regions; i++) {
+			if ((image->regions[i].flags & RFLAG_RW) == 0
+				&& (image->regions[i].flags & RFLAG_REMAPPED) == 0) {
+				// we only need to do this once, so we remember those we've already mapped
+				if (_kern_set_area_protection(image->regions[i].id,
+						B_READ_AREA | B_EXECUTE_AREA) == B_OK) {
+					image->regions[i].flags |= RFLAG_REMAPPED;
+				}
+			}
+		}
+	}
+}
+
+
+void
+register_image(image_t* image, int fd, const char* path)
+{
+	struct stat stat;
+	image_info info;
+
+	// TODO: set these correctly
+	info.id = 0;
+	info.type = image->type;
+	info.sequence = 0;
+	info.init_order = 0;
+	info.init_routine = (void (*)())image->init_routine;
+	info.term_routine = (void (*)())image->term_routine;
+
+	if (_kern_read_stat(fd, NULL, false, &stat, sizeof(struct stat)) == B_OK) {
+		info.device = stat.st_dev;
+		info.node = stat.st_ino;
+	} else {
+		info.device = -1;
+		info.node = -1;
+	}
+
+	strlcpy(info.name, path, sizeof(info.name));
+	info.text = (void *)image->regions[0].vmstart;
+	info.text_size = image->regions[0].vmsize;
+	info.data = (void *)image->regions[1].vmstart;
+	info.data_size = image->regions[1].vmsize;
+	info.api_version = image->api_version;
+	info.abi = image->abi;
+	image->id = _kern_register_image(&info, sizeof(image_info));
+}
+
+
+//! After fork, we lazily rebuild the image IDs of all loaded images.
+status_t
+update_image_ids()
+{
+	for (image_t* image = sLoadedImages.head; image; image = image->next) {
+		status_t status = update_image_id(image);
+		if (status != B_OK)
+			return status;
+	}
+	for (image_t* image = sDisposableImages.head; image; image = image->next) {
+		status_t status = update_image_id(image);
+		if (status != B_OK)
+			return status;
+	}
+
+	gInvalidImageIDs = false;
+	return B_OK;
+}
+
+
+image_queue_t&
+get_loaded_images()
+{
+	return sLoadedImages;
+}
+
+
+image_queue_t&
+get_disposable_images()
+{
+	return sDisposableImages;
+}
+
+
+uint32
+count_loaded_images()
+{
+	return sLoadedImageCount;
+}
+
+
+void
+enqueue_loaded_image(image_t* image)
+{
+	enqueue_image(&sLoadedImages, image);
+	sLoadedImageCount++;
+}
+
+
+void
+dequeue_loaded_image(image_t* image)
+{
+	dequeue_image(&sLoadedImages, image);
+	sLoadedImageCount--;
+}
+
+
+void
+dequeue_disposable_image(image_t* image)
+{
+	dequeue_image(&sDisposableImages, image);
+}
+
+
+image_t*
+find_loaded_image_by_name(char const* name, uint32 typeMask)
+{
+	bool isPath = strchr(name, '/') != NULL;
+	return find_image_in_queue(&sLoadedImages, name, isPath, typeMask);
+}
+
+
+image_t*
+find_loaded_image_by_id(image_id id, bool ignoreDisposable)
+{
+	if (gInvalidImageIDs) {
+		// After fork, we lazily rebuild the image IDs of all loaded images
+		update_image_ids();
+	}
+
+	for (image_t* image = sLoadedImages.head; image; image = image->next) {
+		if (image->id == id)
+			return image;
+	}
+
+	if (ignoreDisposable)
+		return NULL;
+
+	for (image_t* image = sDisposableImages.head; image; image = image->next) {
+		if (image->id == id)
+			return image;
+	}
+
+	return NULL;
+}
+
+
+void
+set_image_flags_recursively(image_t* image, uint32 flags)
+{
+	update_image_flags_recursively(image, flags, 0);
+}
+
+
+void
+clear_image_flags_recursively(image_t* image, uint32 flags)
+{
+	update_image_flags_recursively(image, 0, flags);
+}
+
+
+ssize_t
+get_sorted_image_list(image_t* image, image_t*** _list, uint32 sortFlag)
+{
+	image_t** list;
+
+	list = (image_t**)malloc(sLoadedImageCount * sizeof(image_t*));
+	if (list == NULL) {
+		FATAL("memory shortage in get_sorted_image_list()");
+		*_list = NULL;
+		return B_NO_MEMORY;
+	}
+
+	memset(list, 0, sLoadedImageCount * sizeof(image_t*));
+
+	*_list = list;
+	return topological_sort(image, 0, list, sortFlag);
+}

src/system/runtime_loader/images.h

@@ -0,0 +1,76 @@
+/*
+ * Copyright 2008-2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Copyright 2003-2008, Axel Dörfler, axeld@pinc-software.de.
+ * Distributed under the terms of the MIT License.
+ *
+ * Copyright 2002, Manuel J. Petit. All rights reserved.
+ * Copyright 2001, Travis Geiselbrecht. All rights reserved.
+ * Distributed under the terms of the NewOS License.
+ */
+#ifndef IMAGES_H
+#define IMAGES_H
+
+#include <runtime_loader.h>
+
+
+enum {
+	// the lower two bits are reserved for RTLD_NOW and RTLD_GLOBAL
+
+	RFLAG_RW					= 0x0010,
+	RFLAG_ANON					= 0x0020,
+
+	RFLAG_TERMINATED			= 0x0200,
+	RFLAG_INITIALIZED			= 0x0400,
+	RFLAG_SYMBOLIC				= 0x0800,
+	RFLAG_RELOCATED				= 0x1000,
+	RFLAG_PROTECTED				= 0x2000,
+	RFLAG_DEPENDENCIES_LOADED	= 0x4000,
+	RFLAG_REMAPPED				= 0x8000,
+
+	RFLAG_VISITED				= 0x10000,
+	RFLAG_USE_FOR_RESOLVING		= 0x20000
+		// temporarily set in the symbol resolution code
+};
+
+
+#define IMAGE_TYPE_TO_MASK(type)	(1 << ((type) - 1))
+#define ALL_IMAGE_TYPES				(IMAGE_TYPE_TO_MASK(B_APP_IMAGE) \
+									| IMAGE_TYPE_TO_MASK(B_LIBRARY_IMAGE) \
+									| IMAGE_TYPE_TO_MASK(B_ADD_ON_IMAGE) \
+									| IMAGE_TYPE_TO_MASK(B_SYSTEM_IMAGE))
+#define APP_OR_LIBRARY_TYPE			(IMAGE_TYPE_TO_MASK(B_APP_IMAGE) \
+									| IMAGE_TYPE_TO_MASK(B_LIBRARY_IMAGE))
+
+
+extern bool gInvalidImageIDs;
+
+
+image_t*	create_image(const char* name, const char* path, int regionCount);
+void		delete_image_struct(image_t* image);
+void		delete_image(image_t* image);
+void		put_image(image_t* image);
+
+status_t	map_image(int fd, char const* path, image_t* image, bool fixed);
+void		unmap_image(image_t* image);
+void		remap_images();
+
+void		register_image(image_t* image, int fd, const char* path);
+status_t	update_image_ids();
+
+image_queue_t& get_loaded_images();
+image_queue_t& get_disposable_images();
+uint32		count_loaded_images();
+void		enqueue_loaded_image(image_t* image);
+void		dequeue_loaded_image(image_t* image);
+void		dequeue_disposable_image(image_t* image);
+
+image_t*	find_loaded_image_by_name(char const* name, uint32 typeMask);
+image_t*	find_loaded_image_by_id(image_id id, bool ignoreDisposable);
+
+void		set_image_flags_recursively(image_t* image, uint32 flags);
+void		clear_image_flags_recursively(image_t* image, uint32 flags);
+ssize_t		get_sorted_image_list(image_t* image, image_t*** _list,
+				uint32 sortFlag);
+
+
+#endif	// IMAGES_H

src/system/runtime_loader/runtime_loader.cpp

@@ -20,14 +20,6 @@
 #include <algorithm>
 
 
-//#define TRACE_RLD
-#ifdef TRACE_RLD
-#	define TRACE(x) printf x
-#else
-#	define TRACE(x) ;
-#endif
-
-
 struct user_space_program_args *gProgramArgs;
 
 

src/system/runtime_loader/runtime_loader_private.h

@@ -5,46 +5,74 @@
  * Copyright 2002, Manuel J. Petit. All rights reserved.
  * Distributed under the terms of the NewOS License.
  */
-#ifndef RUNTIME_LOADER_H
-#define RUNTIME_LOADER_H
-
+#ifndef RUNTIME_LOADER_PRIVATE_H
+#define RUNTIME_LOADER_PRIVATE_H
 
 #include <user_runtime.h>
 #include <runtime_loader.h>
 
+#include "tracing_config.h"
 
-extern struct user_space_program_args *gProgramArgs;
+#include "utility.h"
+
+
+//#define TRACE_RLD
+#ifdef TRACE_RLD
+#	define TRACE(x) dprintf x
+#else
+#	define TRACE(x) ;
+#endif
+
+
+#if RUNTIME_LOADER_TRACING
+#	define KTRACE(x...)	ktrace_printf(x)
+#else
+#	define KTRACE(x...)
+#endif	// RUNTIME_LOADER_TRACING
+
+
+#define FATAL(x...)							\
+	do {									\
+		dprintf("runtime_loader: " x);		\
+		if (!gProgramLoaded)				\
+			printf("runtime_loader: " x);	\
+	} while (false)
+
+
+extern struct user_space_program_args* gProgramArgs;
 extern struct rld_export gRuntimeLoader;
-extern char *(*gGetEnv)(const char *name);
+extern char* (*gGetEnv)(const char* name);
+extern bool gProgramLoaded;
+extern image_t* gProgramImage;
 
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-int runtime_loader(void *arg);
-int open_executable(char *name, image_type type, const char *rpath,
-	const char *programPath, const char *compatibilitySubDir);
-status_t test_executable(const char *path, char *interpreter);
+int runtime_loader(void* arg);
+int open_executable(char* name, image_type type, const char* rpath,
+	const char* programPath, const char* compatibilitySubDir);
+status_t test_executable(const char* path, char* interpreter);
 
 void terminate_program(void);
-image_id load_program(char const *path, void **entry);
-image_id load_library(char const *path, uint32 flags, bool addOn,
+image_id load_program(char const* path, void** entry);
+image_id load_library(char const* path, uint32 flags, bool addOn,
 	void** _handle);
 status_t unload_library(void* handle, image_id imageID, bool addOn);
-status_t get_nth_symbol(image_id imageID, int32 num, char *nameBuffer,
-	int32 *_nameLength, int32 *_type, void **_location);
-status_t get_symbol(image_id imageID, char const *symbolName, int32 symbolType,
-	bool recursive, image_id *_inImage, void **_location);
+status_t get_nth_symbol(image_id imageID, int32 num, char* nameBuffer,
+	int32* _nameLength, int32* _type, void** _location);
+status_t get_symbol(image_id imageID, char const* symbolName, int32 symbolType,
+	bool recursive, image_id* _inImage, void** _location);
 status_t get_library_symbol(void* handle, void* caller, const char* symbolName,
-	void **_location);
-status_t get_next_image_dependency(image_id id, uint32 *cookie,
-	const char **_name);
-int resolve_symbol(image_t *rootImage, image_t *image, struct Elf32_Sym *sym,
-	addr_t *sym_addr);
+	void** _location);
+status_t get_next_image_dependency(image_id id, uint32* cookie,
+	const char** _name);
+int resolve_symbol(image_t* rootImage, image_t* image, struct Elf32_Sym* sym,
+	addr_t* sym_addr);
 
 
-status_t elf_verify_header(void *header, int32 length);
+status_t elf_verify_header(void* header, int32 length);
 void rldelf_init(void);
 void rldexport_init(void);
 status_t elf_reinit_after_fork(void);
@@ -52,10 +80,10 @@ status_t elf_reinit_after_fork(void);
 status_t heap_init(void);
 
 // arch dependent prototypes
-status_t arch_relocate_image(image_t *rootImage, image_t *image);
+status_t arch_relocate_image(image_t* rootImage, image_t* image);
 
 #ifdef __cplusplus
 }
 #endif
 
-#endif	/* RUNTIME_LOADER_H */
+#endif	/* RUNTIME_LOADER_PRIVATE_H */

src/system/runtime_loader/utility.cpp

@@ -58,6 +58,21 @@ printf(const char *format, ...)
 }
 
 
+extern "C" void
+dprintf(const char *format, ...)
+{
+	char buffer[1024];
+
+	va_list list;
+	va_start(list, format);
+
+	vsnprintf(buffer, sizeof(buffer), format, list);
+	_kern_debug_output(buffer);
+
+	va_end(list);
+}
+
+
 extern "C" uint32
 __swap_int32(uint32 value)
 {
@@ -79,8 +94,41 @@ _get_thread_info(thread_id thread, thread_info *info, size_t size)
 }
 
 
-status_t
+extern "C" status_t
 snooze(bigtime_t timeout)
 {
 	return B_ERROR;
 }
+
+
+/*!	Mini atoi(), so we don't have to include the libroot dependencies.
+ */
+extern "C" int
+atoi(const char* num)
+{
+	int result = 0;
+	while (*num >= '0' && *num <= '9') {
+		result = (result * 10) + (*num - '0');
+		num++;
+	}
+
+	return result;
+}
+
+
+#if RUNTIME_LOADER_TRACING
+
+extern "C" void
+ktrace_printf(const char *format, ...)
+{
+	va_list list;
+	va_start(list, format);
+
+	char buffer[1024];
+	vsnprintf(buffer, sizeof(buffer), format, list);
+	_kern_ktrace_output(buffer);
+
+	va_end(list);
+}
+
+#endif // RUNTIME_LOADER_TRACING

src/system/runtime_loader/utility.h

@@ -0,0 +1,28 @@
+/*
+ * Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef UTILITY_H
+#define UTILITY_H
+
+#include <OS.h>
+
+
+#define	PAGE_MASK (B_PAGE_SIZE - 1)
+
+#define	PAGE_OFFSET(x) ((x) & (PAGE_MASK))
+#define	PAGE_BASE(x) ((x) & ~(PAGE_MASK))
+#define TO_PAGE_SIZE(x) ((x + (PAGE_MASK)) & ~(PAGE_MASK))
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void dprintf(const char *format, ...);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif	// UTILITY_H