runtime loader: Add support for $ORIGIN in rpath

Like in Linux it resolves to the directory of the shared object whose
needed library is to be loaded.

src/system/runtime_loader/elf.cpp

@@ -119,7 +119,7 @@ load_immediate_dependencies(image_t *image)
 				const char *name = STRING(image, neededOffset);
 
 				status_t loadStatus = load_image(name, B_LIBRARY_IMAGE,
-					rpath, &image->needed[j]);
+					rpath, image->path, &image->needed[j]);
 				if (loadStatus < B_OK) {
 					status = loadStatus;
 					// correct error code in case the file could not been found
@@ -308,7 +308,7 @@ preload_image(char const* path)
 	KTRACE("rld: preload_image(\"%s\")", path);
 
 	image_t *image = NULL;
-	status_t status = load_image(path, B_LIBRARY_IMAGE, NULL, &image);
+	status_t status = load_image(path, B_LIBRARY_IMAGE, NULL, NULL, &image);
 	if (status < B_OK) {
 		KTRACE("rld: preload_image(\"%s\") failed to load container: %s", path,
 			strerror(status));
@@ -410,7 +410,7 @@ load_program(char const *path, void **_entry)
 
 	TRACE(("rld: load %s\n", path));
 
-	status = load_image(path, B_APP_IMAGE, NULL, &gProgramImage);
+	status = load_image(path, B_APP_IMAGE, NULL, NULL, &gProgramImage);
 	if (status < B_OK)
 		goto err;
 
@@ -516,7 +516,7 @@ load_library(char const *path, uint32 flags, bool addOn, void** _handle)
 		}
 	}
 
-	status = load_image(path, type, NULL, &image);
+	status = load_image(path, type, NULL, NULL, &image);
 	if (status < B_OK) {
 		rld_unlock();
 		KTRACE("rld: load_library(\"%s\") failed to load container: %s", path,

src/system/runtime_loader/elf_load_image.cpp

@@ -377,7 +377,7 @@ parse_elf_header(elf_ehdr* eheader, int32* _pheaderSize,
 
 status_t
 load_image(char const* name, image_type type, const char* rpath,
-	image_t** _image)
+	const char* requestingObjectPath, image_t** _image)
 {
 	int32 pheaderSize, sheaderSize;
 	char path[PATH_MAX];
@@ -421,7 +421,7 @@ load_image(char const* name, image_type type, const char* rpath,
 
 	// find and open the file
 	fd = open_executable(path, type, rpath, get_program_path(),
-		sSearchPathSubDir);
+		requestingObjectPath, sSearchPathSubDir);
 	if (fd < 0) {
 		FATAL("Cannot open file %s: %s\n", name, strerror(fd));
 		KTRACE("rld: load_container(\"%s\"): failed to open file", name);

src/system/runtime_loader/elf_load_image.h

@@ -11,7 +11,7 @@
 status_t	parse_elf_header(elf_ehdr* eheader, int32* _pheaderSize,
 				int32* _sheaderSize);
 status_t	load_image(char const* name, image_type type, const char* rpath,
-				image_t** _image);
+				const char* requestingObjectPath, image_t** _image);
 
 
 #endif	// ELF_LOAD_IMAGE_H

src/system/runtime_loader/runtime_loader.cpp

@@ -94,10 +94,59 @@ search_path_for_type(image_type type)
 }
 
 
+static bool
+replace_executable_path_placeholder(const char*& dir, int& dirLength,
+	const char* placeholder, size_t placeholderLength,
+	const char* replacementSubPath, char*& buffer, size_t& bufferSize,
+	status_t& _error)
+{
+	if (dirLength < (int)placeholderLength
+		|| strncmp(dir, placeholder, placeholderLength) != 0) {
+		return false;
+	}
+
+	if (replacementSubPath == NULL) {
+		_error = B_ENTRY_NOT_FOUND;
+		return true;
+	}
+
+	char* lastSlash = strrchr(replacementSubPath, '/');
+
+	// Copy replacementSubPath without the last component (the application file
+	// name, respectively the requesting executable file name).
+	size_t toCopy;
+	if (lastSlash != NULL) {
+		toCopy = lastSlash - replacementSubPath;
+		strlcpy(buffer, replacementSubPath,
+			std::min((ssize_t)bufferSize, lastSlash + 1 - replacementSubPath));
+	} else {
+		replacementSubPath = ".";
+		toCopy = 1;
+		strlcpy(buffer, ".", bufferSize);
+	}
+
+	if (toCopy >= bufferSize) {
+		_error = B_NAME_TOO_LONG;
+		return true;
+	}
+
+	memcpy(buffer, replacementSubPath, toCopy);
+	buffer[toCopy] = '\0';
+
+	buffer += toCopy;
+	bufferSize -= toCopy;
+	dir += placeholderLength;
+	dirLength -= placeholderLength;
+
+	_error = B_OK;
+	return true;
+}
+
+
 static int
 try_open_executable(const char *dir, int dirLength, const char *name,
-	const char *programPath, const char *abiSpecificSubDir, char *path,
-	size_t pathLength)
+	const char *programPath, const char *requestingObjectPath,
+	const char *abiSpecificSubDir, char *path, size_t pathLength)
 {
 	size_t nameLength = strlen(name);
 	struct stat stat;
@@ -111,24 +160,12 @@ try_open_executable(const char *dir, int dirLength, const char *name,
 		if (programPath == NULL)
 			programPath = gProgramArgs->program_path;
 
-		if (dirLength >= 2 && strncmp(dir, "%A", 2) == 0) {
-			// Replace %A with current app folder path (of course,
-			// this must be the first part of the path)
-			char *lastSlash = strrchr(programPath, '/');
-			int bytesCopied;
-
-			// copy what's left (when the application name is removed)
-			if (lastSlash != NULL) {
-				strlcpy(buffer, programPath,
-					std::min((long)pathLength, lastSlash + 1 - programPath));
-			} else
-				strlcpy(buffer, ".", pathLength);
-
-			bytesCopied = strlen(buffer);
-			buffer += bytesCopied;
-			pathLength -= bytesCopied;
-			dir += 2;
-			dirLength -= 2;
+		if (replace_executable_path_placeholder(dir, dirLength, "%A", 2,
+				programPath, buffer, pathLength, status)
+			|| replace_executable_path_placeholder(dir, dirLength, "$ORIGIN", 7,
+				requestingObjectPath, buffer, pathLength, status)) {
+			if (status != B_OK)
+				return status;
 		} else if (abiSpecificSubDir != NULL) {
 			// We're looking for a library or an add-on and the executable has
 			// not been compiled with a compiler using the same ABI as the one
@@ -187,8 +224,8 @@ try_open_executable(const char *dir, int dirLength, const char *name,
 
 static int
 search_executable_in_path_list(const char *name, const char *pathList,
-	int pathListLen, const char *programPath, const char *abiSpecificSubDir,
-	char *pathBuffer, size_t pathBufferLength)
+	int pathListLen, const char *programPath, const char *requestingObjectPath,
+	const char *abiSpecificSubDir, char *pathBuffer, size_t pathBufferLength)
 {
 	const char *pathListEnd = pathList + pathListLen;
 	status_t status = B_ENTRY_NOT_FOUND;
@@ -205,7 +242,8 @@ search_executable_in_path_list(const char *name, const char *pathList,
 			pathEnd++;
 
 		fd = try_open_executable(pathList, pathEnd - pathList, name,
-			programPath, abiSpecificSubDir, pathBuffer, pathBufferLength);
+			programPath, requestingObjectPath, abiSpecificSubDir, pathBuffer,
+			pathBufferLength);
 		if (fd >= 0) {
 			// see if it's a dir
 			struct stat stat;
@@ -228,7 +266,8 @@ search_executable_in_path_list(const char *name, const char *pathList,
 
 int
 open_executable(char *name, image_type type, const char *rpath,
-	const char *programPath, const char *abiSpecificSubDir)
+	const char *programPath, const char *requestingObjectPath,
+	const char *abiSpecificSubDir)
 {
 	char buffer[PATH_MAX];
 	int fd = B_ENTRY_NOT_FOUND;
@@ -266,12 +305,13 @@ open_executable(char *name, image_type type, const char *rpath,
 			// If there is no ';', we set only secondList to simplify things.
 		if (firstList) {
 			fd = search_executable_in_path_list(name, firstList,
-				semicolon - firstList, programPath, NULL, buffer,
-				sizeof(buffer));
+				semicolon - firstList, programPath, requestingObjectPath, NULL,
+				buffer, sizeof(buffer));
 		}
 		if (fd < 0) {
 			fd = search_executable_in_path_list(name, secondList,
-				strlen(secondList), programPath, NULL, buffer, sizeof(buffer));
+				strlen(secondList), programPath, requestingObjectPath, NULL,
+				buffer, sizeof(buffer));
 		}
 	}
 
@@ -280,7 +320,7 @@ open_executable(char *name, image_type type, const char *rpath,
 	if (fd < 0) {
 		if (const char *paths = search_path_for_type(type)) {
 			fd = search_executable_in_path_list(name, paths, strlen(paths),
-				programPath, abiSpecificSubDir, buffer, sizeof(buffer));
+				programPath, NULL, abiSpecificSubDir, buffer, sizeof(buffer));
 		}
 	}
 
@@ -337,7 +377,7 @@ test_executable(const char *name, char *invoker)
 
 	strlcpy(path, name, sizeof(path));
 
-	fd = open_executable(path, B_APP_IMAGE, NULL, NULL, NULL);
+	fd = open_executable(path, B_APP_IMAGE, NULL, NULL, NULL, NULL);
 	if (fd < B_OK)
 		return fd;
 

src/system/runtime_loader/runtime_loader_private.h

@@ -56,7 +56,8 @@ extern "C" {
 
 int runtime_loader(void* arg, void* commpage);
 int open_executable(char* name, image_type type, const char* rpath,
-	const char* programPath, const char* abiSpecificSubDir);
+	const char* programPath, const char* requestingObjectPath,
+	const char* abiSpecificSubDir);
 status_t test_executable(const char* path, char* interpreter);
 status_t get_executable_architecture(const char* path,
 	const char** _architecture);