(unexec): Consider a section to precede the .bss section

if its addresses overlap that of .bss.
(unexec) [NS_IMPL_GNUSTEP]: Copy ObjC-related data from old file
instead of dumping process.

diff --git a/src/ChangeLog b/src/ChangeLog
index b8e23d74d41334da227282d9df21f61cd098da01..f68a937aa5e1a72a15c5f712fb7b9355959b257f 100644 (file)
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,14 @@
+2009-05-06  YAMAMOTO Mitsuharu  <mituharu@math.s.chiba-u.ac.jp>
+
+       * keyboard.h (add_user_signal): Fix typo in extern.
+
+       * lisp.h (add_user_signal): Remove extern.
+
+       * unexelf.c (unexec): Consider a section to precede the .bss section
+       if its addresses overlap that of .bss.
+       (unexec) [NS_IMPL_GNUSTEP]: Copy ObjC-related data from old file
+       instead of dumping process.
+
 2009-05-06  Stefan Monnier  <monnier@iro.umontreal.ca>
 
        * keyboard.c (syms_of_keyboard): Staticpro pending_funcalls.

diff --git a/src/unexelf.c b/src/unexelf.c
index 83e57003759a7ac3e107d5d833470881f49be829..45de52dffda6e0c22d23ff041b45ef874b65ca17 100644 (file)
--- a/src/unexelf.c
+++ b/src/unexelf.c
@@ -985,9 +985,29 @@ unexec (new_name, old_name, data_start, bss_start, entry_address)
             placed after the .bss section.  Overlap can occur if the
             section just before .bss has less-strict alignment; this
             was observed between .symtab and .bss on Solaris 2.5.1
-            (sparc) with GCC snapshot 960602.  */
+            (sparc) with GCC snapshot 960602.
 
-         if (NEW_SECTION_H (nn).sh_offset >= old_bss_offset)
+> dump -h temacs
+
+temacs:
+
+          **** SECTION HEADER TABLE ****
+[No]   Type    Flags   Addr         Offset       Size          Name
+       Link    Info    Adralgn      Entsize
+
+[22]   1       3       0x335150     0x315150     0x4           .data.rel.local
+       0       0       0x4          0            
+
+[23]   8       3       0x335158     0x315158     0x42720       .bss
+       0       0       0x8          0            
+
+[24]   2       0       0            0x315154     0x1c9d0       .symtab
+       25      1709    0x4          0x10         
+         */
+
+         if (NEW_SECTION_H (nn).sh_offset >= old_bss_offset
+             || (NEW_SECTION_H (nn).sh_offset + NEW_SECTION_H (nn).sh_size
+                 > new_data2_offset))
            NEW_SECTION_H (nn).sh_offset += new_data2_incr;
 
          /* Any section that was originally placed after the section
@@ -1206,11 +1226,41 @@ unexec (new_name, old_name, data_start, bss_start, entry_address)
       symendp = (ElfW(Sym) *) ((byte *)symp + NEW_SECTION_H (n).sh_size);
 
       for (; symp < symendp; symp ++)
-       if (strcmp ((char *) (symnames + symp->st_name), "_end") == 0
-           || strcmp ((char *) (symnames + symp->st_name), "end") == 0
-           || strcmp ((char *) (symnames + symp->st_name), "_edata") == 0
-           || strcmp ((char *) (symnames + symp->st_name), "edata") == 0)
-         memcpy (&symp->st_value, &new_bss_addr, sizeof (new_bss_addr));
+       {
+         if (strcmp ((char *) (symnames + symp->st_name), "_end") == 0
+             || strcmp ((char *) (symnames + symp->st_name), "end") == 0
+             || strcmp ((char *) (symnames + symp->st_name), "_edata") == 0
+             || strcmp ((char *) (symnames + symp->st_name), "edata") == 0)
+           memcpy (&symp->st_value, &new_bss_addr, sizeof (new_bss_addr));
+
+         /* Strictly speaking, #ifdef below is not necessary.  But we
+            keep it to indicate that this kind of change may also be
+            necessary for other unexecs to support GNUstep.  */
+#ifdef NS_IMPL_GNUSTEP
+         /* ObjC runtime modifies the values of some data structures
+            such as classes and selectors in the .data section after
+            loading.  As the dump process copies the .data section
+            from the current process, that causes problems when the
+            modified classes are reinitialized in the dumped
+            executable.  We copy such data from the old file, not
+            from the current process.  */
+         if (strncmp ((char *) (symnames + symp->st_name),
+                      "_OBJC_", sizeof ("_OBJC_") - 1) == 0)
+           {
+             caddr_t old, new;
+
+             new = ((symp->st_value - NEW_SECTION_H (symp->st_shndx).sh_addr)
+                    + NEW_SECTION_H (symp->st_shndx).sh_offset + new_base);
+             /* "Unpatch" index.  */
+             nn = symp->st_shndx;
+             if (nn > old_bss_index)
+               nn--;
+             old = ((symp->st_value - NEW_SECTION_H (symp->st_shndx).sh_addr)
+                    + OLD_SECTION_H (nn).sh_offset + old_base);
+             memcpy (new, old, symp->st_size);
+           }
+#endif
+       }
     }
 
   /* This loop seeks out relocation sections for the data section, so