Ticket #8064: 0001-Fix-dladdr-behaviour.patch

headers/private/runtime_loader/runtime_loader.h

@@ -36 +36 @@
     status_t (*get_nth_image_symbol)(image_id imageID, int32 num,
         char *symbolName, int32 *nameLength, int32 *symbolType,
         void **_location);
-    status_t (*get_symbol_at_address)(void* address, image_id* _imageID,
-        char* nameBuffer, int32* _nameLength, int32* _type, void** _location);
+    status_t (*get_nearest_symbol_at_address)(void* address,
+        image_id* _imageID, char** _imagePath, char** _symName, int32* _type,
+        void** _location);
     status_t (*test_executable)(const char *path, char *interpreter);
     status_t (*get_next_image_dependency)(image_id id, uint32 *cookie,
         const char **_name);

src/system/libroot/posix/dlfcn.c

@@ -74 +74 @@
 int
 dladdr(void *address, Dl_info *info)
 {
-    static char sImageName[MAXPATHLEN];
-    static char sSymbolName[NAME_MAX];
-
     image_id image;
-    int32 nameLength = sizeof(sSymbolName);
+    char* imagePath;
+    char* symName;
     void* location;
     image_info imageInfo;
-    sStatus = __gRuntimeLoader->get_symbol_at_address(address, &image,
-        sSymbolName, &nameLength, NULL, &location);
+
+    sStatus = __gRuntimeLoader->get_nearest_symbol_at_address(address, &image,
+        &imagePath, &symName, NULL, &location);
     if (sStatus != B_OK)
         return 0;
 
@@ -90 +89 @@
     if (sStatus != B_OK)
         return 0;
 
-    strlcpy(sImageName, imageInfo.name, MAXPATHLEN);
-    info->dli_fname = sImageName;
+    info->dli_fname = imagePath;
     info->dli_fbase = imageInfo.text;
-    info->dli_sname = sSymbolName;
+    info->dli_sname = symName;
     info->dli_saddr = location;
-
     return 1;
 }
 

src/system/runtime_loader/elf.cpp

@@ -710 +710 @@
 
 
 status_t
-get_symbol_at_address(void* address, image_id* _imageID, char* nameBuffer,
-    int32* _nameLength, int32* _type, void** _location)
+get_nearest_symbol_at_address(void* address, image_id* _imageID,
+    char** _imagePath, char** _symName, int32* _type, void** _location)
 {
     rld_lock();
 
@@ -721 +721 @@
         return B_BAD_VALUE;
     }
 
+    struct Elf32_Sym* foundSym = NULL;
+    addr_t foundLocation = (addr_t)NULL;
+
     for (uint32 i = 0; i < HASHTABSIZE(image); i++) {
         for (int32 j = HASHBUCKETS(image)[i]; j != STN_UNDEF;
                 j = HASHCHAINS(image)[j]) {
             struct Elf32_Sym *symbol = &image->syms[j];
             addr_t location = symbol->st_value + image->regions[0].delta;
 
-            if (location <= (addr_t)address
-                && location - 1 + symbol->st_size >= (addr_t)address) {
-                const char* symbolName = SYMNAME(image, symbol);
-                strlcpy(nameBuffer, symbolName, *_nameLength);
-                *_nameLength = strlen(symbolName);
-
-                int32 type;
-                if (ELF32_ST_TYPE(symbol->st_info) == STT_FUNC)
-                    type = B_SYMBOL_TYPE_TEXT;
-                else if (ELF32_ST_TYPE(symbol->st_info) == STT_OBJECT)
-                    type = B_SYMBOL_TYPE_DATA;
-                else
-                    type = B_SYMBOL_TYPE_ANY;
-                    // TODO: check with the return types of that BeOS function
-
-                if (_imageID != NULL)
-                    *_imageID = image->id;
-                if (_type != NULL)
-                    *_type = type;
-                if (_location != NULL)
-                    *_location = (void*)location;
+            if (location <= (addr_t)address && location >= foundLocation) {
+                foundSym = symbol;
+                foundLocation = location;
 
-                rld_unlock();
-                return B_OK;
+                // jump out if we have an exact match
+                if (foundLocation == (addr_t)address)
+                    goto out;
             }
         }
     }
 
+out:
+    if (_imageID != NULL)
+        *_imageID = image->id;
+    if (_imagePath != NULL)
+        *_imagePath = image->path;
+
+    if (foundSym != NULL) {
+        *_symName = SYMNAME(image, foundSym);
+
+        if (_type != NULL) {
+            if (ELF32_ST_TYPE(foundSym->st_info) == STT_FUNC)
+                *_type = B_SYMBOL_TYPE_TEXT;
+            else if (ELF32_ST_TYPE(foundSym->st_info) == STT_OBJECT)
+                *_type = B_SYMBOL_TYPE_DATA;
+            else
+                *_type = B_SYMBOL_TYPE_ANY;
+            // TODO: check with the return types of that BeOS function
+        }
+
+        if (_location != NULL)
+            *_location = (void*)foundLocation;
+    } else {
+        *_symName = NULL;
+        if (_location != NULL)
+            *_location = NULL;
+    }
+
     rld_unlock();
-    return B_BAD_VALUE;
+    return B_OK;
 }
 
 

src/system/runtime_loader/export.cpp

@@ -51 +51 @@
     get_symbol,
     get_library_symbol,
     get_nth_symbol,
-    get_symbol_at_address,
+    get_nearest_symbol_at_address,
     test_executable,
     get_next_image_dependency,
 

src/system/runtime_loader/runtime_loader_private.h

@@ -65 +65 @@
 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_at_address(void* address, image_id* _imageID,
-    char* nameBuffer, int32* _nameLength, int32* _type, void** _location);
+status_t get_nearest_symbol_at_address(void* address, image_id* _imageID,
+    char** _imagePath, char** _symName, 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,