+dwfl_report_elf_baseaddr

4 files changed, 43 insertions, 9 deletions

diff --git a/libdwfl/dwfl_report_elf.c b/libdwfl/dwfl_report_elf.c
index d7061704..08ad37c8 100644
--- a/libdwfl/dwfl_report_elf.c
+++ b/libdwfl/dwfl_report_elf.c
@@ -41,7 +41,8 @@
 Dwfl_Module *
 internal_function
 __libdwfl_report_elf (Dwfl *dwfl, const char *name, const char *file_name,
-		      int fd, Elf *elf, GElf_Addr base, bool sanity)
+		      int fd, Elf *elf, GElf_Addr base, bool base_is_bias,
+		      bool sanity)
 {
   GElf_Ehdr ehdr_mem, *ehdr = gelf_getehdr (elf, &ehdr_mem);
   if (ehdr == NULL)
@@ -181,11 +182,19 @@ __libdwfl_report_elf (Dwfl *dwfl, const char *name, const char *file_name,
 	    {
 	      vaddr = ph->p_vaddr & -ph->p_align;
 	      address_sync = ph->p_vaddr + ph->p_memsz;
-	      start = base + vaddr;
 	      break;
 	    }
 	}
-      bias = base;
+      if (base_is_bias)
+	{
+	  start = base + vaddr;
+	  bias = base;
+	}
+      else
+	{
+	  start = base;
+	  bias = base - vaddr;
+	}
 
       for (size_t i = phnum; i-- > 0;)
 	{
@@ -195,7 +204,7 @@ __libdwfl_report_elf (Dwfl *dwfl, const char *name, const char *file_name,
 	  if (ph->p_type == PT_LOAD
 	      && ph->p_vaddr + ph->p_memsz > 0)
 	    {
-	      end = base + (ph->p_vaddr + ph->p_memsz);
+	      end = bias + (ph->p_vaddr + ph->p_memsz);
 	      break;
 	    }
 	}
@@ -246,8 +255,9 @@ __libdwfl_report_elf (Dwfl *dwfl, const char *name, const char *file_name,
 }
 
 Dwfl_Module *
-dwfl_report_elf (Dwfl *dwfl, const char *name,
-		 const char *file_name, int fd, GElf_Addr base)
+internal_function
+__libdwfl_report_elf_open (Dwfl *dwfl, const char *name, const char *file_name,
+			   int fd, GElf_Addr base, bool base_is_bias)
 {
   bool closefd = false;
   if (fd < 0)
@@ -270,7 +280,7 @@ dwfl_report_elf (Dwfl *dwfl, const char *name,
     }
 
   Dwfl_Module *mod = __libdwfl_report_elf (dwfl, name, file_name,
-					   fd, elf, base, true);
+					   fd, elf, base, base_is_bias, true);
   if (mod == NULL)
     {
       elf_end (elf);
@@ -280,4 +290,19 @@ dwfl_report_elf (Dwfl *dwfl, const char *name,
 
   return mod;
 }
+
+Dwfl_Module *
+dwfl_report_elf (Dwfl *dwfl, const char *name,
+		 const char *file_name, int fd, GElf_Addr base)
+{
+  return __libdwfl_report_elf_open (dwfl, name, file_name, fd, base, true);
+}
 INTDEF (dwfl_report_elf)
+
+Dwfl_Module *
+dwfl_report_elf_baseaddr (Dwfl *dwfl, const char *name,
+			  const char *file_name, int fd, GElf_Addr base)
+{
+  return __libdwfl_report_elf_open (dwfl, name, file_name, fd, base, false);
+}
+INTDEF (dwfl_report_elf_baseaddr)
diff --git a/libdwfl/libdwfl.h b/libdwfl/libdwfl.h
index 8498c0cd..a2ab8246 100644
--- a/libdwfl/libdwfl.h
+++ b/libdwfl/libdwfl.h
@@ -146,6 +146,13 @@ extern Dwfl_Module *dwfl_report_elf (Dwfl *dwfl, const char *name,
 				     const char *file_name, int fd,
 				     GElf_Addr base);
 
+/* See dwfl_report_elf except that BASE is the page-aligned absolute VMA
+   address where the ELF file should start.  Any possible file prelinking of
+   the disk file is compensated.  */
+extern Dwfl_Module *dwfl_report_elf_baseaddr (Dwfl *dwfl, const char *name,
+					      const char *file_name, int fd,
+					      GElf_Addr base);
+
 /* Similar, but report the module for offline use.  All ET_EXEC files
    being reported must be reported before any relocatable objects.
    If this is used, dwfl_report_module and dwfl_report_elf may not be
diff --git a/libdwfl/libdwflP.h b/libdwfl/libdwflP.h
index ca8be2f2..e5e638c9 100644
--- a/libdwfl/libdwflP.h
+++ b/libdwfl/libdwflP.h
@@ -353,7 +353,8 @@ extern int __libdwfl_crc32_file (int fd, uint32_t *resp) attribute_hidden;
    Consumes ELF on success, not on failure.  */
 extern Dwfl_Module *__libdwfl_report_elf (Dwfl *dwfl, const char *name,
 					  const char *file_name, int fd,
-					  Elf *elf, GElf_Addr base, bool sanity)
+					  Elf *elf, GElf_Addr base,
+					  bool base_is_bias, bool sanity)
   internal_function;
 
 /* Meat of dwfl_report_offline.  */
diff --git a/libdwfl/offline.c b/libdwfl/offline.c
index 26a6bd66..28d2782e 100644
--- a/libdwfl/offline.c
+++ b/libdwfl/offline.c
@@ -127,7 +127,8 @@ process_elf (Dwfl *dwfl, const char *name, const char *file_name, int fd,
 	     Elf *elf)
 {
   Dwfl_Module *mod = __libdwfl_report_elf (dwfl, name, file_name, fd, elf,
-					   dwfl->offline_next_address, false);
+					   dwfl->offline_next_address, true,
+					   false);
   if (mod != NULL)
     {
       /* If this is an ET_EXEC file with fixed addresses, the address range