segment_report_module: Use a struct for build id information

Keep the three build id fields in a struct. This will be an important
clean up later.

Signed-off-by: Timm Bäder <tbaeder@redhat.com>

diff --git a/libdwfl/ChangeLog b/libdwfl/ChangeLog
index 7123b1824efa24467ed1a61d6b11ee590e9d4709..19c78e4ff7a2506dbc14c45b32fd42ad372aa37c 100644 (file)
--- a/libdwfl/ChangeLog
+++ b/libdwfl/ChangeLog
@@ -1,3 +1,8 @@
+2020-11-23  Timm Bäder  <tbaeder@redhat.com>
+
+       * segment_report_module.c (struct elf_build_id): New.
+       (dwfl_segment_report_module): Pass build_id as struct.
+
 2020-11-23  Timm Bäder  <tbaeder@redhat.com>
 
        * segment_report_module.c (dwfl_segment_report_module): Remove

diff --git a/libdwfl/dwfl_segment_report_module.c b/libdwfl/dwfl_segment_report_module.c
index 6399d5d9343143c36c994de00f0ca6dc2a70801a..af8c6b59678ce8174c74758f4a68a0ab1c30e68a 100644 (file)
--- a/libdwfl/dwfl_segment_report_module.c
+++ b/libdwfl/dwfl_segment_report_module.c
@@ -54,6 +54,13 @@
 # define MY_ELFDATA    ELFDATA2MSB
 #endif
 
+struct elf_build_id
+{
+  void *memory;
+  size_t len;
+  GElf_Addr vaddr;
+};
+
 
 /* Return user segment index closest to ADDR but not above it.
    If NEXT, return the closest to ADDR but not below it.  */
@@ -206,16 +213,16 @@ handle_file_note (GElf_Addr module_start, GElf_Addr module_end,
 
 static bool
 invalid_elf (Elf *elf, bool disk_file_has_build_id,
-            const void *build_id, size_t build_id_len)
+             struct elf_build_id *build_id)
 {
-  if (! disk_file_has_build_id && build_id_len > 0)
+  if (! disk_file_has_build_id && build_id->len > 0)
     {
       /* Module found in segments with build-id is more reliable
         than a module found via DT_DEBUG on disk without any
         build-id.   */
       return true;
     }
-  if (disk_file_has_build_id && build_id_len > 0)
+  if (disk_file_has_build_id && build_id->len > 0)
     {
       const void *elf_build_id;
       ssize_t elf_build_id_len;
@@ -224,8 +231,8 @@ invalid_elf (Elf *elf, bool disk_file_has_build_id,
       elf_build_id_len = INTUSE(dwelf_elf_gnu_build_id) (elf, &elf_build_id);
       if (elf_build_id_len > 0)
        {
-         if (build_id_len != (size_t) elf_build_id_len
-             || memcmp (build_id, elf_build_id, build_id_len) != 0)
+         if (build_id->len != (size_t) elf_build_id_len
+             || memcmp (build_id->memory, elf_build_id, build_id->len) != 0)
            return true;
        }
     }
@@ -429,16 +436,17 @@ dwfl_segment_report_module (Dwfl *dwfl, int ndx, const char *name,
   GElf_Xword dyn_filesz = 0;
 
   /* Collect the build ID bits here.  */
-  void *build_id = NULL;
-  size_t build_id_len = 0;
-  GElf_Addr build_id_vaddr = 0;
+  struct elf_build_id build_id;
+  build_id.memory = NULL;
+  build_id.len = 0;
+  build_id.vaddr =0;
 
   /* Consider a PT_NOTE we've found in the image.  */
   inline void consider_notes (GElf_Addr vaddr, GElf_Xword filesz,
                              GElf_Xword align)
   {
     /* If we have already seen a build ID, we don't care any more.  */
-    if (build_id != NULL || filesz == 0)
+    if (build_id.memory != NULL || filesz == 0)
       return;
 
     void *data;
@@ -495,11 +503,11 @@ dwfl_segment_report_module (Dwfl *dwfl, int ndx, const char *name,
            && nh->n_namesz == sizeof "GNU"
            && !memcmp (note_name, "GNU", sizeof "GNU"))
          {
-           build_id_vaddr = note_desc - (const void *) notes + vaddr;
-           build_id_len = nh->n_descsz;
-           build_id = malloc (nh->n_descsz);
-           if (likely (build_id != NULL))
-             memcpy (build_id, note_desc, build_id_len);
+           build_id.vaddr = note_desc - (const void *) notes + vaddr;
+           build_id.len = nh->n_descsz;
+           build_id.memory = malloc (build_id.len);
+           if (likely (build_id.memory != NULL))
+             memcpy (build_id.memory, note_desc, build_id.len);
            break;
          }
 
@@ -614,7 +622,7 @@ dwfl_segment_report_module (Dwfl *dwfl, int ndx, const char *name,
      header we read at START was not produced by these program headers.  */
   if (unlikely (!found_bias))
     {
-      free (build_id);
+      free (build_id.memory);
       goto out;
     }
 
@@ -669,7 +677,7 @@ dwfl_segment_report_module (Dwfl *dwfl, int ndx, const char *name,
          {
            if (module->elf != NULL
                && invalid_elf (module->elf, module->disk_file_has_build_id,
-                               build_id, build_id_len))
+                               &build_id))
              {
                elf_end (module->elf);
                close (module->fd);
@@ -685,7 +693,7 @@ dwfl_segment_report_module (Dwfl *dwfl, int ndx, const char *name,
          }
       if (skip_this_module)
        {
-         free (build_id);
+         free (build_id.memory);
          goto out;
        }
     }
@@ -704,7 +712,7 @@ dwfl_segment_report_module (Dwfl *dwfl, int ndx, const char *name,
          Dwfl_Error error = __libdw_open_file (&fd, &elf, true, false);
          if (error == DWFL_E_NOERROR)
            invalid = invalid_elf (elf, true /* disk_file_has_build_id */,
-                                  build_id, build_id_len);
+                                   &build_id);
        }
       if (invalid)
        {
@@ -848,11 +856,11 @@ dwfl_segment_report_module (Dwfl *dwfl, int ndx, const char *name,
   if (mod != NULL && (execlike || ehdr.e32.e_type == ET_EXEC))
     mod->is_executable = true;
 
-  if (likely (mod != NULL) && build_id != NULL
+  if (likely (mod != NULL) && build_id.memory != NULL
       && unlikely (INTUSE(dwfl_module_report_build_id) (mod,
-                                                       build_id,
-                                                       build_id_len,
-                                                       build_id_vaddr)))
+                                                       build_id.memory,
+                                                       build_id.len,
+                                                       build_id.vaddr)))
     {
       mod->gc = true;
       mod = NULL;
@@ -860,7 +868,7 @@ dwfl_segment_report_module (Dwfl *dwfl, int ndx, const char *name,
 
   /* At this point we do not need BUILD_ID or NAME any more.
      They have been copied.  */
-  free (build_id);
+  free (build_id.memory);
   finish_portion (&soname, &soname_size);
 
   if (unlikely (mod == NULL))