From: Tom Tromey <tom@tromey.com>
Date: Sat, 24 Aug 2024 14:37:15 +0000 (-0600)
Subject: Capture the current directory and debug directory in DWARF reader
X-Git-Tag: gdb-16-branchpoint~631
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=3fbf1a34f10aa6a67d9f96c437e8f9dc57832d22;p=thirdparty%2Fbinutils-gdb.git

Capture the current directory and debug directory in DWARF reader

This changes the DWARF reader to capture the current working directory
and the current debug directory.  This avoids races when the DWARF
reader is working in the background.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31716
---

diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c
index 95498bf01ed..bd2de028d1d 100644
--- a/gdb/dwarf2/read.c
+++ b/gdb/dwarf2/read.c
@@ -1252,7 +1252,9 @@ line_header_eq_voidp (const void *item_lhs, const void *item_rhs)
 dwarf2_per_bfd::dwarf2_per_bfd (bfd *obfd, const dwarf2_debug_sections *names,
 				bool can_copy_)
   : obfd (obfd),
-    can_copy (can_copy_)
+    can_copy (can_copy_),
+    captured_cwd (current_directory),
+    captured_debug_dir (debug_file_directory)
 {
   if (names == NULL)
     names = &dwarf2_elf_names;
@@ -9046,10 +9048,12 @@ try_open_dwop_file (dwarf2_per_objfile *per_objfile,
   gdb::unique_xmalloc_ptr<char> search_path_holder;
   if (search_cwd)
     {
-      if (!debug_file_directory.empty ())
+      const std::string &debug_dir = per_objfile->per_bfd->captured_debug_dir;
+
+      if (!debug_dir.empty ())
 	{
 	  search_path_holder.reset (concat (".", dirname_separator_string,
-					    debug_file_directory.c_str (),
+					    debug_dir.c_str (),
 					    (char *) NULL));
 	  search_path = search_path_holder.get ();
 	}
@@ -9057,7 +9061,7 @@ try_open_dwop_file (dwarf2_per_objfile *per_objfile,
 	search_path = ".";
     }
   else
-    search_path = debug_file_directory.c_str ();
+    search_path = per_objfile->per_bfd->captured_debug_dir.c_str ();
 
   /* Add the path for the executable binary to the list of search paths.  */
   std::string objfile_dir = ldirname (objfile_name (per_objfile->objfile));
@@ -9072,7 +9076,8 @@ try_open_dwop_file (dwarf2_per_objfile *per_objfile,
 
   gdb::unique_xmalloc_ptr<char> absolute_name;
   desc = openp (search_path, flags, file_name,
-		O_RDONLY | O_BINARY, &absolute_name);
+		O_RDONLY | O_BINARY, &absolute_name,
+		per_objfile->per_bfd->captured_cwd.c_str ());
   if (desc < 0)
     return NULL;
 
@@ -9126,7 +9131,7 @@ open_dwo_file (dwarf2_per_objfile *per_objfile,
   /* That didn't work, try debug-file-directory, which, despite its name,
      is a list of paths.  */
 
-  if (debug_file_directory.empty ())
+  if (per_objfile->per_bfd->captured_debug_dir.empty ())
     return NULL;
 
   return try_open_dwop_file (per_objfile, file_name,
@@ -9407,7 +9412,7 @@ open_dwp_file (dwarf2_per_objfile *per_objfile, const char *file_name)
      [IWBN if the dwp file name was recorded in the executable, akin to
      .gnu_debuglink, but that doesn't exist yet.]
      Strip the directory from FILE_NAME and search again.  */
-  if (!debug_file_directory.empty ())
+  if (!per_objfile->per_bfd->captured_debug_dir.empty ())
     {
       /* Don't implicitly search the current directory here.
 	 If the user wants to search "." to handle this case,
diff --git a/gdb/dwarf2/read.h b/gdb/dwarf2/read.h
index 7c42017c3d6..728f2b55224 100644
--- a/gdb/dwarf2/read.h
+++ b/gdb/dwarf2/read.h
@@ -558,6 +558,12 @@ public:
   std::unordered_map<sect_offset, std::vector<sect_offset>,
 		     gdb::hash_enum<sect_offset>>
     abstract_to_concrete;
+
+  /* Current directory, captured at the moment that object this was
+     created.  */
+  std::string captured_cwd;
+  /* Captured copy of debug_file_directory.  */
+  std::string captured_debug_dir;
 };
 
 /* An iterator for all_units that is based on index.  This