[PATCH v3 2/3] dbghelp: Search debug info with buildid for RSDS debug entry w/o filenames.

[Eric Pouech]

From: Eric Pouech

Signed-off-by: Eric Pouech 
---
 dlls/dbghelp/dbghelp_private.h |  2 ++
 dlls/dbghelp/module.c          | 20 ++++++++++++++++++--
 dlls/dbghelp/pe_module.c       | 24 ++++++++++++++++++++++++
 3 files changed, 44 insertions(+), 2 deletions(-)

diff --git a/dlls/dbghelp/dbghelp_private.h b/dlls/dbghelp/dbghelp_private.h
index d8761bd599a..8def6a7dae6 100644
--- a/dlls/dbghelp/dbghelp_private.h
+++ b/dlls/dbghelp/dbghelp_private.h
@@ -788,6 +788,8 @@ extern BOOL         pe_unmap_directory(struct module* module, int dirno, const c
 extern DWORD        pe_get_file_indexinfo(void* image, DWORD size, SYMSRV_INDEX_INFOW* info);
 extern const BYTE*  pe_lock_region_from_rva(struct module *module, DWORD rva, DWORD size, DWORD *length);
 extern BOOL         pe_unlock_region(struct module *module, const BYTE* region);
+struct image_file_map;
+extern BOOL         pe_has_buildid_debug(struct image_file_map *fmap, GUID *guid);

/* source.c */
 extern unsigned     source_new(struct module* module, const char* basedir, const char* source);
diff --git a/dlls/dbghelp/module.c b/dlls/dbghelp/module.c
index 478017900dd..b8848f4010a 100644
--- a/dlls/dbghelp/module.c
+++ b/dlls/dbghelp/module.c
@@ -527,6 +527,7 @@ static BOOL image_check_debug_link_gnu_id(const WCHAR* file, struct image_file_m
 {
     struct image_section_map buildid_sect;
     DWORD read_bytes;
+    GUID guid;
     HANDLE handle;
     WCHAR *path;
     WORD magic;
@@ -545,6 +546,9 @@ static BOOL image_check_debug_link_gnu_id(const WCHAR* file, struct image_file_m
         ret = elf_map_handle(handle, fmap);
     CloseHandle(handle);

+    if (ret && pe_has_buildid_debug(fmap, &guid))
+        return TRUE;
+
     if (ret && image_find_section(fmap, ".note.gnu.build-id", &buildid_sect))
     {
         const UINT32* note;
@@ -557,12 +561,13 @@ static BOOL image_check_debug_link_gnu_id(const WCHAR* file, struct image_file_m
             {
                 if (note[1] == idlen && !memcmp(note + 3 + ((note[0] + 3) >> 2), id, idlen))
                     return TRUE;
-                WARN("mismatch in buildid information for %s\n", debugstr_w(file));
             }
         }
         image_unmap_section(&buildid_sect);
         image_unmap_file(fmap);
     }
+    if (ret)
+        WARN("mismatch in buildid information for %s\n", debugstr_w(file));
     return FALSE;
 }

@@ -844,7 +849,18 @@ BOOL image_check_alternate(struct image_file_map* fmap, const struct module* mod
     struct image_file_map* fmap_link = NULL;

/* if present, add the .gnu_debuglink file as an alternate to current one */
-    if (image_find_section(fmap, ".note.gnu.build-id", &buildid_sect))
+    if (fmap->modtype == DMT_PE)
+    {
+        GUID guid;
+
+        if (pe_has_buildid_debug(fmap, &guid))
+        {
+            /* reorder bytes to match little endian order */
+            fmap_link = image_locate_build_id_target((const BYTE*)&guid, sizeof(guid));
+        }
+    }
+    /* if present, add the .note.gnu.build-id as an alternate to current one */
+    if (!fmap_link && image_find_section(fmap, ".note.gnu.build-id", &buildid_sect))
     {
         const UINT32* note;

diff --git a/dlls/dbghelp/pe_module.c b/dlls/dbghelp/pe_module.c
index 75060e2dfa6..bd3d6000535 100644
--- a/dlls/dbghelp/pe_module.c
+++ b/dlls/dbghelp/pe_module.c
@@ -1036,3 +1036,27 @@ DWORD pe_get_file_indexinfo(void* image, DWORD size, SYMSRV_INDEX_INFOW* info)
     }
     return msc_get_file_indexinfo(image, dbg, dirsize / sizeof(*dbg), info);
 }
+
+/* check if image contains a debug entry that contains a gcc/mingw - clang build-id information */
+BOOL pe_has_buildid_debug(struct image_file_map *fmap, GUID *guid)
+{
+    BOOL ret = FALSE;
+
+    if (fmap->modtype == DMT_PE)
+    {
+        SYMSRV_INDEX_INFOW info = {.sizeofstruct = sizeof(info)};
+        const void *image = pe_map_full(fmap, NULL);
+
+        if (image)
+        {
+            DWORD retval = pe_get_file_indexinfo((void*)image, GetFileSize(fmap->u.pe.hMap, NULL), &info);
+            if ((retval == ERROR_SUCCESS || retval == ERROR_BAD_EXE_FORMAT) && info.age && !info.pdbfile[0])
+            {
+                *guid = info.guid;
+                ret = TRUE;
+            }
+            pe_unmap_full(fmap);
+        }
+    }
+    return ret;
+}