-/* Copyright (C) 1985, 1986, 1987, 1988, 1990, 1992, 1999, 2000, 2001,
- 2002, 2003, 2004, 2005, 2006, 2007, 2008
+/* Copyright (C) 1985-1988, 1990, 1992, 1999-2012
Free Software Foundation, Inc.
This file is part of GNU Emacs.
* unexec.c - Convert a running program into an a.out file.
*
* Author: Spencer W. Thomas
- * Computer Science Dept.
- * University of Utah
+ * Computer Science Dept.
+ * University of Utah
* Date: Tue Mar 2 1982
* Modified heavily since then.
*
* Synopsis:
- * unexec (new_name, old_name, data_start, bss_start, entry_address)
- * char *new_name, *old_name;
- * unsigned data_start, bss_start, entry_address;
+ * unexec (const char *new_name, const char *old_name);
*
* Takes a snapshot of the program and makes an a.out format file in the
* file named by the string argument new_name.
* If old_name is non-NULL, the symbol table will be taken from the given file.
* On some machines, an existing old_name file is required.
*
- * The boundaries within the a.out file may be adjusted with the data_start
- * and bss_start arguments. Either or both may be given as 0 for defaults.
- *
- * Data_start gives the boundary between the text segment and the data
- * segment of the program. The text segment can contain shared, read-only
- * program code and literal data, while the data segment is always unshared
- * and unprotected. Data_start gives the lowest unprotected address.
- * The value you specify may be rounded down to a suitable boundary
- * as required by the machine you are using.
- *
- * Bss_start indicates how much of the data segment is to be saved in the
- * a.out file and restored when the program is executed. It gives the lowest
- * unsaved address, and is rounded up to a page boundary. The default when 0
- * is given assumes that the entire data segment is to be stored, including
- * the previous data and bss as well as any additional storage allocated with
- * break (2).
- *
- * The new file is set up to start at entry_address.
- *
*/
/* Even more heavily modified by james@bigtex.cactus.org of Dell Computer Co.
/* We do not use mmap because that fails with NFS.
Instead we read the whole file, modify it, and write it out. */
-#ifndef emacs
-#define fatal(a, b, c) fprintf (stderr, a, b, c), exit (1)
-#include <string.h>
-#else
#include <config.h>
+#include <unexec.h>
+
extern void fatal (const char *msgid, ...);
-#endif
#include <sys/types.h>
+#include <stdint.h>
#include <stdio.h>
#include <sys/stat.h>
#include <memory.h>
#include <fcntl.h>
#if !defined (__NetBSD__) && !defined (__OpenBSD__)
#include <elf.h>
-#endif
+#endif /* not __NetBSD__ and not __OpenBSD__ */
#include <sys/mman.h>
#if defined (_SYSTYPE_SYSV)
#include <sys/elf_mips.h>
long cbRfdOffset;
long cbExtOffset;
} HDRR, *pHDRR;
-#define cbHDRR sizeof(HDRR)
+#define cbHDRR sizeof (HDRR)
#define hdrNil ((pHDRR)0)
#endif
#endif
#ifndef ElfW
-# ifdef __STDC__
-# define ElfBitsW(bits, type) Elf##bits##_##type
-# else
-# define ElfBitsW(bits, type) Elf/**/bits/**/_/**/type
-# endif
+# define ElfBitsW(bits, type) Elf##bits##_##type
# ifdef _LP64
# define ELFSIZE 64
# else
# define ElfW(type) ElfExpandBitsW (ELFSIZE, type)
#endif
-#ifndef ELF_BSS_SECTION_NAME
-#define ELF_BSS_SECTION_NAME ".bss"
-#endif
-
/* Get the address of a particular section or program header entry,
* accounting for the size of the entries.
*/
*/
#define OLD_SECTION_H(n) \
- (*(ElfW(Shdr) *) ((byte *) old_section_h + old_file_h->e_shentsize * (n)))
+ (*(ElfW (Shdr) *) ((byte *) old_section_h + old_file_h->e_shentsize * (n)))
#define NEW_SECTION_H(n) \
- (*(ElfW(Shdr) *) ((byte *) new_section_h + new_file_h->e_shentsize * (n)))
-#define OLD_PROGRAM_H(n) \
- (*(ElfW(Phdr) *) ((byte *) old_program_h + old_file_h->e_phentsize * (n)))
+ (*(ElfW (Shdr) *) ((byte *) new_section_h + new_file_h->e_shentsize * (n)))
#define NEW_PROGRAM_H(n) \
- (*(ElfW(Phdr) *) ((byte *) new_program_h + new_file_h->e_phentsize * (n)))
+ (*(ElfW (Phdr) *) ((byte *) new_program_h + new_file_h->e_phentsize * (n)))
#define PATCH_INDEX(n) \
do { \
/* Round X up to a multiple of Y. */
-static ElfW(Addr)
-round_up (x, y)
- ElfW(Addr) x, y;
+static ElfW (Addr)
+round_up (ElfW (Addr) x, ElfW (Addr) y)
{
int rem = x % y;
if (rem == 0)
if NOERROR is 0; we return -1 if NOERROR is nonzero. */
static int
-find_section (name, section_names, file_name, old_file_h, old_section_h, noerror)
- char *name;
- char *section_names;
- char *file_name;
- ElfW(Ehdr) *old_file_h;
- ElfW(Shdr) *old_section_h;
- int noerror;
+find_section (const char *name, const char *section_names, const char *file_name,
+ ElfW (Ehdr) *old_file_h, ElfW (Shdr) *old_section_h, int noerror)
{
int idx;
*
*/
void
-unexec (new_name, old_name, data_start, bss_start, entry_address)
- char *new_name, *old_name;
- unsigned data_start, bss_start, entry_address;
+unexec (const char *new_name, const char *old_name)
{
int new_file, old_file, new_file_size;
+#if defined (emacs) || !defined (DEBUG)
+ void *new_break;
+#endif
+
/* Pointers to the base of the image of the two files. */
caddr_t old_base, new_base;
/* Pointers to the file, program and section headers for the old and
new files. */
- ElfW(Ehdr) *old_file_h, *new_file_h;
- ElfW(Phdr) *old_program_h, *new_program_h;
- ElfW(Shdr) *old_section_h, *new_section_h;
+ ElfW (Ehdr) *old_file_h, *new_file_h;
+ ElfW (Phdr) *old_program_h, *new_program_h;
+ ElfW (Shdr) *old_section_h, *new_section_h;
/* Point to the section name table in the old file. */
char *old_section_names;
- ElfW(Addr) old_bss_addr, new_bss_addr;
- ElfW(Word) old_bss_size, new_data2_size;
- ElfW(Off) new_data2_offset;
- ElfW(Addr) new_data2_addr;
+ ElfW (Addr) old_bss_addr, new_bss_addr;
+ ElfW (Word) old_bss_size, new_data2_size;
+ ElfW (Off) new_data2_offset;
+ ElfW (Addr) new_data2_addr;
+ ElfW (Off) old_bss_offset;
+ ElfW (Word) new_data2_incr;
int n, nn;
int old_bss_index, old_sbss_index, old_plt_index;
int old_data_index, new_data2_index;
+#if defined _SYSTYPE_SYSV || defined __sgi
int old_mdebug_index;
+#endif
struct stat stat_buf;
int old_file_size;
/* Get pointers to headers & section names */
- old_file_h = (ElfW(Ehdr) *) old_base;
- old_program_h = (ElfW(Phdr) *) ((byte *) old_base + old_file_h->e_phoff);
- old_section_h = (ElfW(Shdr) *) ((byte *) old_base + old_file_h->e_shoff);
+ old_file_h = (ElfW (Ehdr) *) old_base;
+ old_program_h = (ElfW (Phdr) *) ((byte *) old_base + old_file_h->e_phoff);
+ old_section_h = (ElfW (Shdr) *) ((byte *) old_base + old_file_h->e_shoff);
old_section_names = (char *) old_base
+ OLD_SECTION_H (old_file_h->e_shstrndx).sh_offset;
/* Find the mdebug section, if any. */
+#if defined _SYSTYPE_SYSV || defined __sgi
old_mdebug_index = find_section (".mdebug", old_section_names,
old_name, old_file_h, old_section_h, 1);
+#endif
/* Find the old .bss section. Figure out parameters of the new
data2 and bss sections. */
{
old_bss_addr = OLD_SECTION_H (old_bss_index).sh_addr;
old_bss_size = OLD_SECTION_H (old_bss_index).sh_size;
+ old_bss_offset = OLD_SECTION_H (old_bss_index).sh_offset;
new_data2_index = old_bss_index;
}
else if (old_plt_index != -1
+ OLD_SECTION_H (old_plt_index).sh_size;
if (old_sbss_index != -1)
old_bss_size += OLD_SECTION_H (old_sbss_index).sh_size;
+ old_bss_offset = OLD_SECTION_H (old_plt_index).sh_offset;
new_data2_index = old_plt_index;
}
else
old_bss_addr = OLD_SECTION_H (old_sbss_index).sh_addr;
old_bss_size = OLD_SECTION_H (old_bss_index).sh_size
+ OLD_SECTION_H (old_sbss_index).sh_size;
+ old_bss_offset = OLD_SECTION_H (old_sbss_index).sh_offset;
new_data2_index = old_sbss_index;
}
old_name, old_file_h, old_section_h, 0);
#if defined (emacs) || !defined (DEBUG)
- new_bss_addr = (ElfW(Addr)) sbrk (0);
+ new_break = sbrk (0);
+ new_bss_addr = (ElfW (Addr)) new_break;
#else
new_bss_addr = old_bss_addr + old_bss_size + 0x1234;
#endif
new_data2_addr = old_bss_addr;
new_data2_size = new_bss_addr - old_bss_addr;
- new_data2_offset = OLD_SECTION_H (old_data_index).sh_offset +
- (new_data2_addr - OLD_SECTION_H (old_data_index).sh_addr);
+ new_data2_offset = OLD_SECTION_H (old_data_index).sh_offset
+ + (new_data2_addr - OLD_SECTION_H (old_data_index).sh_addr);
+ /* This is the amount by which the sections following the bss sections
+ must be shifted in the image. It can differ from new_data2_size if
+ the end of the old .data section (and thus the offset of the .bss
+ section) was unaligned. */
+ new_data2_incr = new_data2_size + (new_data2_offset - old_bss_offset);
#ifdef DEBUG
fprintf (stderr, "old_bss_index %d\n", old_bss_index);
fprintf (stderr, "old_bss_addr %x\n", old_bss_addr);
fprintf (stderr, "old_bss_size %x\n", old_bss_size);
+ fprintf (stderr, "old_bss_offset %x\n", old_bss_offset);
fprintf (stderr, "new_bss_addr %x\n", new_bss_addr);
fprintf (stderr, "new_data2_addr %x\n", new_data2_addr);
fprintf (stderr, "new_data2_size %x\n", new_data2_size);
fprintf (stderr, "new_data2_offset %x\n", new_data2_offset);
+ fprintf (stderr, "new_data2_incr %x\n", new_data2_incr);
#endif
- if ((unsigned) new_bss_addr < (unsigned) old_bss_addr + old_bss_size)
+ if ((uintptr_t) new_bss_addr < (uintptr_t) old_bss_addr + old_bss_size)
fatal (".bss shrank when undumping???\n", 0, 0);
/* Set the output file to the right size. Allocate a buffer to hold
if (new_file < 0)
fatal ("Can't creat (%s): errno %d\n", new_name, errno);
- new_file_size = stat_buf.st_size + old_file_h->e_shentsize + new_data2_size;
+ new_file_size = stat_buf.st_size + old_file_h->e_shentsize + new_data2_incr;
if (ftruncate (new_file, new_file_size))
fatal ("Can't ftruncate (%s): errno %d\n", new_name, errno);
if (new_base == MAP_FAILED)
fatal ("Can't allocate buffer for %s\n", old_name, 0);
- new_file_h = (ElfW(Ehdr) *) new_base;
- new_program_h = (ElfW(Phdr) *) ((byte *) new_base + old_file_h->e_phoff);
- new_section_h = (ElfW(Shdr) *)
- ((byte *) new_base + old_file_h->e_shoff + new_data2_size);
+ new_file_h = (ElfW (Ehdr) *) new_base;
+ new_program_h = (ElfW (Phdr) *) ((byte *) new_base + old_file_h->e_phoff);
+ new_section_h = (ElfW (Shdr) *)
+ ((byte *) new_base + old_file_h->e_shoff + new_data2_incr);
/* Make our new file, program and section headers as copies of the
originals. */
/* Fix up file header. We'll add one section. Section header is
further away now. */
- new_file_h->e_shoff += new_data2_size;
+ new_file_h->e_shoff += new_data2_incr;
new_file_h->e_shnum += 1;
#ifdef DEBUG
for (n = new_file_h->e_phnum - 1; n >= 0; n--)
{
/* Compute maximum of all requirements for alignment of section. */
- ElfW(Word) alignment = (NEW_PROGRAM_H (n)).p_align;
+ ElfW (Word) alignment = (NEW_PROGRAM_H (n)).p_align;
if ((OLD_SECTION_H (old_bss_index)).sh_addralign > alignment)
alignment = OLD_SECTION_H (old_bss_index).sh_addralign;
NEW_PROGRAM_H (n).p_vaddr += new_data2_size - old_bss_size;
if (NEW_PROGRAM_H (n).p_offset >= new_data2_offset)
- NEW_PROGRAM_H (n).p_offset += new_data2_size;
+ NEW_PROGRAM_H (n).p_offset += new_data2_incr;
}
#endif
gets its value adjusted. .bss size becomes zero and new address
is set. data2 section header gets added by copying the existing
.data header and modifying the offset, address and size. */
- for (old_data_index = 1; old_data_index < (int) old_file_h->e_shnum;
- old_data_index++)
- if (!strcmp (old_section_names + OLD_SECTION_H (old_data_index).sh_name,
- ".data"))
- break;
- if (old_data_index == old_file_h->e_shnum)
- fatal ("Can't find .data in %s.\n", old_name, 0);
/* Walk through all section headers, insert the new data2 section right
before the new bss section. */
)
{
/* NN should be `old_s?bss_index + 1' at this point. */
- NEW_SECTION_H (nn).sh_offset =
- NEW_SECTION_H (new_data2_index).sh_offset + new_data2_size;
- NEW_SECTION_H (nn).sh_addr =
- NEW_SECTION_H (new_data2_index).sh_addr + new_data2_size;
+ NEW_SECTION_H (nn).sh_offset = new_data2_offset + new_data2_size;
+ NEW_SECTION_H (nn).sh_addr = new_data2_addr + new_data2_size;
/* Let the new bss section address alignment be the same as the
section address alignment followed the old bss section, so
this section will be placed in exactly the same place. */
else
{
/* Any section that was originally placed after the .bss
- section should now be off by NEW_DATA2_SIZE. If a
+ section should now be off by NEW_DATA2_INCR. If a
section overlaps the .bss section, consider it to be
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.
+
+> 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 + NEW_SECTION_H (nn).sh_size
- > new_data2_offset)
- NEW_SECTION_H (nn).sh_offset += new_data2_size;
+ 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
header table should now be off by the size of one section
/* The conditional bit below was in Oliva's original code
(1999-08-25) and seems to have been dropped by mistake
subsequently. It prevents a crash at startup under X in
- `IRIX64 6.5 6.5.17m', whether compiled on that relase or
+ `IRIX64 6.5 6.5.17m', whether compiled on that release or
an earlier one. It causes no trouble on the other ELF
platforms I could test (Irix 6.5.15m, Solaris 8, Debian
Potato x86, Debian Woody SPARC); however, it's reported
memcpy (NEW_SECTION_H (nn).sh_offset + new_base, src,
NEW_SECTION_H (nn).sh_size);
-#ifdef __alpha__
+#if defined __alpha__ && !defined __OpenBSD__
/* Update Alpha COFF symbol table: */
if (strcmp (old_section_names + OLD_SECTION_H (n).sh_name, ".mdebug")
== 0)
symhdr->cbRfdOffset += new_data2_size;
symhdr->cbExtOffset += new_data2_size;
}
-#endif /* __alpha__ */
+#endif /* __alpha__ && !__OpenBSD__ */
#if defined (_SYSTYPE_SYSV)
if (NEW_SECTION_H (nn).sh_type == SHT_MIPS_DEBUG
&& old_mdebug_index != -1)
- {
- int diff = NEW_SECTION_H(nn).sh_offset
- - OLD_SECTION_H(old_mdebug_index).sh_offset;
+ {
+ int diff = NEW_SECTION_H (nn).sh_offset
+ - OLD_SECTION_H (old_mdebug_index).sh_offset;
HDRR *phdr = (HDRR *)(NEW_SECTION_H (nn).sh_offset + new_base);
if (diff)
if (NEW_SECTION_H (nn).sh_type == SHT_SYMTAB
|| NEW_SECTION_H (nn).sh_type == SHT_DYNSYM)
{
- ElfW(Shdr) *spt = &NEW_SECTION_H (nn);
+ ElfW (Shdr) *spt = &NEW_SECTION_H (nn);
unsigned int num = spt->sh_size / spt->sh_entsize;
- ElfW(Sym) * sym = (ElfW(Sym) *) (NEW_SECTION_H (nn).sh_offset +
+ ElfW (Sym) * sym = (ElfW (Sym) *) (NEW_SECTION_H (nn).sh_offset +
new_base);
for (; num--; sym++)
{
for (n = new_file_h->e_shnum - 1; n; n--)
{
byte *symnames;
- ElfW(Sym) *symp, *symendp;
+ ElfW (Sym) *symp, *symendp;
if (NEW_SECTION_H (n).sh_type != SHT_DYNSYM
&& NEW_SECTION_H (n).sh_type != SHT_SYMTAB)
symnames = ((byte *) new_base
+ NEW_SECTION_H (NEW_SECTION_H (n).sh_link).sh_offset);
- symp = (ElfW(Sym) *) (NEW_SECTION_H (n).sh_offset + new_base);
- symendp = (ElfW(Sym) *) ((byte *)symp + NEW_SECTION_H (n).sh_size);
+ symp = (ElfW (Sym) *) (NEW_SECTION_H (n).sh_offset + new_base);
+ 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--;
+ if (nn == old_bss_index)
+ memset (new, 0, symp->st_size);
+ else
+ {
+ 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
that it can undo relocations performed by the runtime linker. */
for (n = new_file_h->e_shnum - 1; n; n--)
{
- ElfW(Shdr) section = NEW_SECTION_H (n);
+ ElfW (Shdr) section = NEW_SECTION_H (n);
/* Cause a compilation error if anyone uses n instead of nn below. */
- struct {int a;} n;
- (void)n.a; /* Prevent `unused variable' warnings. */
+ #define n ((void) 0);
+ n /* Prevent 'macro "n" is not used' warnings. */
switch (section.sh_type)
{
|| !strcmp ((old_section_names + NEW_SECTION_H (nn).sh_name),
".data1"))
{
- ElfW(Addr) offset = (NEW_SECTION_H (nn).sh_addr
+ ElfW (Addr) offset = (NEW_SECTION_H (nn).sh_addr
- NEW_SECTION_H (nn).sh_offset);
caddr_t reloc = old_base + section.sh_offset, end;
for (end = reloc + section.sh_size; reloc < end;
reloc += section.sh_entsize)
{
- ElfW(Addr) addr = ((ElfW(Rel) *) reloc)->r_offset - offset;
+ ElfW (Addr) addr = ((ElfW (Rel) *) reloc)->r_offset - offset;
#ifdef __alpha__
/* The Alpha ELF binutils currently have a bug that
sometimes results in relocs that contain all
zeroes. Work around this for now... */
- if (((ElfW(Rel) *) reloc)->r_offset == 0)
+ if (((ElfW (Rel) *) reloc)->r_offset == 0)
continue;
#endif
- memcpy (new_base + addr, old_base + addr, sizeof(ElfW(Addr)));
+ memcpy (new_base + addr, old_base + addr, sizeof (ElfW (Addr)));
}
}
break;
}
+
+ #undef n
}
/* Write out new_file, and free the buffers. */
if (write (new_file, new_base, new_file_size) != new_file_size)
-#ifndef emacs
- fatal ("Didn't write %d bytes: errno %d\n",
- new_file_size, errno);
-#else
fatal ("Didn't write %d bytes to %s: errno %d\n",
- new_file_size, new_base, errno);
-#endif
+ new_file_size, new_name, errno);
munmap (old_base, old_file_size);
munmap (new_base, new_file_size);
if (chmod (new_name, stat_buf.st_mode) == -1)
fatal ("Can't chmod (%s): errno %d\n", new_name, errno);
}
-
-/* arch-tag: e02e1512-95e2-4ef0-bba7-b6bce658f1e3
- (do not change this comment) */
HCoop / bpt / emacs.git / blobdiff