DOS executable program before the coff image to load it in memory
and execute it. This is needed, because DOS cannot run coff files.
- All the functions below are called by the corresponding functions
- from coffswap.h.
- The only thing what they do is to adjust the information stored in
- the COFF file which are offset into the file.
- This is needed, because DJGPP uses a very special way to load and run
- the coff image. It loads the image in memory and assumes then, that the
- image had no stub by using the filepointers as pointers in the coff
- image and NOT in the file.
-
- To be compatible with any existing executables I have fixed this
- here and NOT in the DJGPP startup code. */
+ The COFF image is loaded in memory without the stub attached, so
+ all offsets are relative to the beginning of the image, not the
+ actual file. We handle this in bfd by setting bfd->origin to where
+ the COFF image starts. */
#define TARGET_SYM i386_coff_go32stubbed_vec
#define TARGET_NAME "coff-go32-exe"
#include "sysdep.h"
#include "bfd.h"
+#include "coff/msdos.h"
-/* All that ..._PRE and ...POST functions are called from the corresponding
- coff_swap... functions. The ...PRE functions are called at the beginning
- of the function and the ...POST functions at the end of the swap routines. */
+static bfd_cleanup go32exe_check_format (bfd *);
+static bfd_boolean go32exe_write_object_contents (bfd *);
+static bfd_boolean go32exe_mkobject (bfd *);
+static bfd_boolean go32exe_copy_private_bfd_data (bfd *, bfd *);
-static void
-adjust_filehdr_in_post (bfd *, void *, void *);
-static void
-adjust_filehdr_out_pre (bfd *, void *, void *);
-static void
-adjust_filehdr_out_post (bfd *, void *, void *);
-static void
-adjust_scnhdr_in_post (bfd *, void *, void *);
-static void
-adjust_scnhdr_out_pre (bfd *, void *, void *);
-static void
-adjust_scnhdr_out_post (bfd *, void *, void *);
-static void
-adjust_aux_in_post (bfd *, void *, int, int, int, int, void *);
-static void
-adjust_aux_out_pre (bfd *, void *, int, int, int, int, void *);
-static void
-adjust_aux_out_post (bfd *, void *, int, int, int, int, void *);
-static void
-create_go32_stub (bfd *);
-
-#define COFF_ADJUST_FILEHDR_IN_POST adjust_filehdr_in_post
-#define COFF_ADJUST_FILEHDR_OUT_PRE adjust_filehdr_out_pre
-#define COFF_ADJUST_FILEHDR_OUT_POST adjust_filehdr_out_post
-
-#define COFF_ADJUST_SCNHDR_IN_POST adjust_scnhdr_in_post
-#define COFF_ADJUST_SCNHDR_OUT_PRE adjust_scnhdr_out_pre
-#define COFF_ADJUST_SCNHDR_OUT_POST adjust_scnhdr_out_post
-
-#define COFF_ADJUST_AUX_IN_POST adjust_aux_in_post
-#define COFF_ADJUST_AUX_OUT_PRE adjust_aux_out_pre
-#define COFF_ADJUST_AUX_OUT_POST adjust_aux_out_post
-
-static bfd_cleanup go32_check_format (bfd *);
-
-#define COFF_CHECK_FORMAT go32_check_format
-
-static bfd_boolean
- go32_stubbed_coff_bfd_copy_private_bfd_data (bfd *, bfd *);
-
-#define coff_bfd_copy_private_bfd_data go32_stubbed_coff_bfd_copy_private_bfd_data
+#define COFF_CHECK_FORMAT go32exe_check_format
+#define COFF_WRITE_CONTENTS go32exe_write_object_contents
+#define coff_mkobject go32exe_mkobject
+#define coff_bfd_copy_private_bfd_data go32exe_copy_private_bfd_data
#include "coff-i386.c"
/* These bytes are a 2048-byte DOS executable, which loads the COFF
image into memory and then runs it. It is called 'stub'. */
-
-static const unsigned char stub_bytes[GO32_STUBSIZE] =
+#define GO32EXE_DEFAULT_STUB_SIZE 2048
+static const unsigned char go32exe_default_stub[GO32EXE_DEFAULT_STUB_SIZE] =
{
#include "go32stub.h"
};
-/*
- I have not commented each swap function below, because the
- technique is in any function the same. For the ...in function,
- all the pointers are adjusted by adding GO32_STUBSIZE and for the
- ...out function, it is subtracted first and after calling the
- standard swap function it is reset to the old value. */
-
-/* This macro is used for adjusting the filepointers, which
- is done only, if the pointer is nonzero. */
-
-#define ADJUST_VAL(val,diff) \
- if (val != 0) val += diff
-
-static void
-adjust_filehdr_in_post (bfd * abfd ATTRIBUTE_UNUSED,
- void * src,
- void * dst)
-{
- FILHDR *filehdr_src = (FILHDR *) src;
- struct internal_filehdr *filehdr_dst = (struct internal_filehdr *) dst;
-
- ADJUST_VAL (filehdr_dst->f_symptr, GO32_STUBSIZE);
-
- /* Save now the stub to be used later. Put the stub data to FILEHDR_DST
- first as coff_data (abfd) still does not exist. It may not even be ever
- created as we are just checking the file format of ABFD. */
- memcpy (filehdr_dst->go32stub, filehdr_src->stub, GO32_STUBSIZE);
- filehdr_dst->f_flags |= F_GO32STUB;
-}
-
-static void
-adjust_filehdr_out_pre (bfd * abfd, void * in, void * out)
-{
- struct internal_filehdr *filehdr_in = (struct internal_filehdr *) in;
- FILHDR *filehdr_out = (FILHDR *) out;
-
- /* Generate the stub. */
- create_go32_stub (abfd);
-
- /* Copy the stub to the file header. */
- if (coff_data (abfd)->go32stub != NULL)
- memcpy (filehdr_out->stub, coff_data (abfd)->go32stub, GO32_STUBSIZE);
- else
- /* Use the default. */
- memcpy (filehdr_out->stub, stub_bytes, GO32_STUBSIZE);
-
- ADJUST_VAL (filehdr_in->f_symptr, -GO32_STUBSIZE);
-}
-
-static void
-adjust_filehdr_out_post (bfd * abfd ATTRIBUTE_UNUSED,
- void * in,
- void * out ATTRIBUTE_UNUSED)
-{
- struct internal_filehdr *filehdr_in = (struct internal_filehdr *) in;
- /* Undo the above change. */
- ADJUST_VAL (filehdr_in->f_symptr, GO32_STUBSIZE);
-}
-
-static void
-adjust_scnhdr_in_post (bfd * abfd ATTRIBUTE_UNUSED,
- void * ext ATTRIBUTE_UNUSED,
- void * in)
-{
- struct internal_scnhdr *scnhdr_int = (struct internal_scnhdr *) in;
-
- ADJUST_VAL (scnhdr_int->s_scnptr, GO32_STUBSIZE);
- ADJUST_VAL (scnhdr_int->s_relptr, GO32_STUBSIZE);
- ADJUST_VAL (scnhdr_int->s_lnnoptr, GO32_STUBSIZE);
-}
-
-static void
-adjust_scnhdr_out_pre (bfd * abfd ATTRIBUTE_UNUSED,
- void * in,
- void * out ATTRIBUTE_UNUSED)
-{
- struct internal_scnhdr *scnhdr_int = (struct internal_scnhdr *) in;
-
- ADJUST_VAL (scnhdr_int->s_scnptr, -GO32_STUBSIZE);
- ADJUST_VAL (scnhdr_int->s_relptr, -GO32_STUBSIZE);
- ADJUST_VAL (scnhdr_int->s_lnnoptr, -GO32_STUBSIZE);
-}
-
-static void
-adjust_scnhdr_out_post (bfd * abfd ATTRIBUTE_UNUSED,
- void * in,
- void * out ATTRIBUTE_UNUSED)
-{
- struct internal_scnhdr *scnhdr_int = (struct internal_scnhdr *) in;
-
- ADJUST_VAL (scnhdr_int->s_scnptr, GO32_STUBSIZE);
- ADJUST_VAL (scnhdr_int->s_relptr, GO32_STUBSIZE);
- ADJUST_VAL (scnhdr_int->s_lnnoptr, GO32_STUBSIZE);
-}
-
-static void
-adjust_aux_in_post (bfd * abfd ATTRIBUTE_UNUSED,
- void * ext1 ATTRIBUTE_UNUSED,
- int type,
- int in_class,
- int indx ATTRIBUTE_UNUSED,
- int numaux ATTRIBUTE_UNUSED,
- void * in1)
-{
- union internal_auxent *in = (union internal_auxent *) in1;
-
- if (in_class == C_BLOCK || in_class == C_FCN || ISFCN (type)
- || ISTAG (in_class))
- {
- ADJUST_VAL (in->x_sym.x_fcnary.x_fcn.x_lnnoptr, GO32_STUBSIZE);
- }
-}
-
-static void
-adjust_aux_out_pre (bfd *abfd ATTRIBUTE_UNUSED,
- void * inp,
- int type,
- int in_class,
- int indx ATTRIBUTE_UNUSED,
- int numaux ATTRIBUTE_UNUSED,
- void * extp ATTRIBUTE_UNUSED)
-{
- union internal_auxent *in = (union internal_auxent *) inp;
-
- if (in_class == C_BLOCK || in_class == C_FCN || ISFCN (type)
- || ISTAG (in_class))
- {
- ADJUST_VAL (in->x_sym.x_fcnary.x_fcn.x_lnnoptr, -GO32_STUBSIZE);
- }
-}
-
-static void
-adjust_aux_out_post (bfd *abfd ATTRIBUTE_UNUSED,
- void * inp,
- int type,
- int in_class,
- int indx ATTRIBUTE_UNUSED,
- int numaux ATTRIBUTE_UNUSED,
- void * extp ATTRIBUTE_UNUSED)
-{
- union internal_auxent *in = (union internal_auxent *) inp;
-
- if (in_class == C_BLOCK || in_class == C_FCN || ISFCN (type)
- || ISTAG (in_class))
- {
- ADJUST_VAL (in->x_sym.x_fcnary.x_fcn.x_lnnoptr, GO32_STUBSIZE);
- }
-}
+/* Temporary location for stub read from input file. */
+static char * go32exe_temp_stub = NULL;
+static bfd_size_type go32exe_temp_stub_size = 0;
/* That's the function, which creates the stub. There are
different cases from where the stub is taken.
file.
If there was any error, the standard stub (compiled in this file)
- is taken. */
+ is taken.
+
+ Ideally this function should exec '$(TARGET)-stubify' to generate
+ a stub, like gcc does. */
static void
-create_go32_stub (bfd *abfd)
+go32exe_create_stub (bfd *abfd)
{
/* Do it only once. */
- if (coff_data (abfd)->go32stub == NULL)
+ if (coff_data (abfd)->stub == NULL)
{
char *stub;
struct stat st;
unsigned long coff_start;
long exe_start;
+ /* If we read a stub from an input file, use that one. */
+ if (go32exe_temp_stub != NULL)
+ {
+ coff_data (abfd)->stub = bfd_alloc (abfd,
+ go32exe_temp_stub_size);
+ if (coff_data (abfd)->stub == NULL)
+ return;
+ memcpy (coff_data (abfd)->stub, go32exe_temp_stub,
+ go32exe_temp_stub_size);
+ coff_data (abfd)->stub_size = go32exe_temp_stub_size;
+ free (go32exe_temp_stub);
+ go32exe_temp_stub = NULL;
+ go32exe_temp_stub_size = 0;
+ return;
+ }
+
/* Check at first the environment variable $(GO32STUB). */
stub = getenv ("GO32STUB");
/* Now check the environment variable $(STUB). */
if (_H (1))
coff_start += (long) _H (1) - 512L;
- /* Currently there is only a fixed stub size of 2048 bytes
- supported. */
- if (coff_start != 2048)
- {
- close (f);
- goto stub_end;
- }
exe_start = _H (4) * 16;
if ((long) lseek (f, exe_start, SEEK_SET) != exe_start)
{
goto stub_end;
}
/* Now we found a correct stub (hopefully). */
- coff_data (abfd)->go32stub = bfd_alloc (abfd, (bfd_size_type) coff_start);
- if (coff_data (abfd)->go32stub == NULL)
+ coff_data (abfd)->stub = bfd_alloc (abfd, (bfd_size_type) coff_start);
+ if (coff_data (abfd)->stub == NULL)
{
close (f);
return;
}
lseek (f, 0L, SEEK_SET);
- if ((unsigned long) read (f, coff_data (abfd)->go32stub, coff_start)
+ if ((unsigned long) read (f, coff_data (abfd)->stub, coff_start)
!= coff_start)
{
- bfd_release (abfd, coff_data (abfd)->go32stub);
- coff_data (abfd)->go32stub = NULL;
+ bfd_release (abfd, coff_data (abfd)->stub);
+ coff_data (abfd)->stub = NULL;
}
+ else
+ coff_data (abfd)->stub_size = coff_start;
close (f);
}
stub_end:
/* There was something wrong above, so use now the standard builtin
stub. */
- if (coff_data (abfd)->go32stub == NULL)
+ if (coff_data (abfd)->stub == NULL)
{
- coff_data (abfd)->go32stub
- = bfd_alloc (abfd, (bfd_size_type) GO32_STUBSIZE);
- if (coff_data (abfd)->go32stub == NULL)
+ coff_data (abfd)->stub
+ = bfd_alloc (abfd, (bfd_size_type) GO32EXE_DEFAULT_STUB_SIZE);
+ if (coff_data (abfd)->stub == NULL)
return;
- memcpy (coff_data (abfd)->go32stub, stub_bytes, GO32_STUBSIZE);
+ memcpy (coff_data (abfd)->stub, go32exe_default_stub,
+ GO32EXE_DEFAULT_STUB_SIZE);
+ coff_data (abfd)->stub_size = GO32EXE_DEFAULT_STUB_SIZE;
}
}
to the new obfd. */
static bfd_boolean
-go32_stubbed_coff_bfd_copy_private_bfd_data (bfd *ibfd, bfd *obfd)
+go32exe_copy_private_bfd_data (bfd *ibfd, bfd *obfd)
{
/* Check if both are the same targets. */
if (ibfd->xvec != obfd->xvec)
return TRUE;
- /* Check if we have a source stub. */
- if (coff_data (ibfd)->go32stub == NULL)
- return TRUE;
+ /* Make sure we have a source stub. */
+ BFD_ASSERT (coff_data (ibfd)->stub != NULL);
- /* As adjust_filehdr_out_pre may get called only after this function,
- optionally allocate the output stub. */
- if (coff_data (obfd)->go32stub == NULL)
- coff_data (obfd)->go32stub = bfd_alloc (obfd,
- (bfd_size_type) GO32_STUBSIZE);
+ /* Reallocate the output stub if necessary. */
+ if (coff_data (ibfd)->stub_size > coff_data (obfd)->stub_size)
+ coff_data (obfd)->stub = bfd_alloc (obfd, coff_data (ibfd)->stub_size);
+ if (coff_data (obfd)->stub == NULL)
+ return FALSE;
/* Now copy the stub. */
- if (coff_data (obfd)->go32stub != NULL)
- memcpy (coff_data (obfd)->go32stub, coff_data (ibfd)->go32stub,
- GO32_STUBSIZE);
+ memcpy (coff_data (obfd)->stub, coff_data (ibfd)->stub,
+ coff_data (ibfd)->stub_size);
+ coff_data (obfd)->stub_size = coff_data (ibfd)->stub_size;
+ obfd->origin = coff_data (obfd)->stub_size;
return TRUE;
}
-/* coff_object_p only checks 2 bytes F_MAGIC at GO32_STUBSIZE inside the file
- which is too fragile. */
+/* Cleanup function, returned from check_format hook. */
-static bfd_cleanup
-go32_check_format (bfd *abfd)
+static void
+go32exe_cleanup (bfd *abfd)
{
- char mz[2];
+ abfd->origin = 0;
+
+ if (go32exe_temp_stub != NULL)
+ free (go32exe_temp_stub);
+ go32exe_temp_stub = NULL;
+ go32exe_temp_stub_size = 0;
+}
- if (bfd_bread (mz, 2, abfd) != 2 || mz[0] != 'M' || mz[1] != 'Z')
+/* Check that there is a GO32 stub and read it to go32exe_temp_stub.
+ Then set abfd->origin so that the COFF image is read at the correct
+ file offset. */
+
+static bfd_cleanup
+go32exe_check_format (bfd *abfd)
+{
+ struct external_DOS_hdr filehdr_dos;
+ uint16_t num_pages;
+ uint16_t last_page_size;
+ uint32_t header_end;
+ bfd_size_type stubsize;
+
+ /* This format can not appear in an archive. */
+ if (abfd->origin != 0)
{
bfd_set_error (bfd_error_wrong_format);
return NULL;
}
+ bfd_set_error (bfd_error_system_call);
+
+ /* Read in the stub file header, which is a DOS MZ executable. */
+ if (bfd_bread (&filehdr_dos, DOS_HDR_SIZE, abfd) != DOS_HDR_SIZE)
+ goto fail;
+
+ /* Make sure that this is an MZ executable. */
+ if (H_GET_16 (abfd, filehdr_dos.e_magic) != IMAGE_DOS_SIGNATURE)
+ goto fail_format;
+
+ /* Determine the size of the stub */
+ num_pages = H_GET_16 (abfd, filehdr_dos.e_cp);
+ last_page_size = H_GET_16 (abfd, filehdr_dos.e_cblp);
+ stubsize = num_pages * 512;
+ if (last_page_size != 0)
+ stubsize += last_page_size - 512;
+
+ /* Save now the stub to be used later. Put the stub data to a temporary
+ location first as tdata still does not exist. It may not even
+ be ever created if we are just checking the file format of ABFD. */
+ bfd_seek (abfd, 0, SEEK_SET);
+ go32exe_temp_stub = bfd_malloc (stubsize);
+ if (go32exe_temp_stub == NULL)
+ goto fail;
+ if (bfd_bread (go32exe_temp_stub, stubsize, abfd) != stubsize)
+ goto fail;
+ go32exe_temp_stub_size = stubsize;
+
+ /* Confirm that this is a go32stub. */
+ header_end = H_GET_16 (abfd, filehdr_dos.e_cparhdr) * 16UL;
+ if (! CONST_STRNEQ (go32exe_temp_stub + header_end, "go32stub"))
+ goto fail_format;
+
+ /* Set origin to where the COFF header starts and seek there. */
+ abfd->origin = stubsize;
if (bfd_seek (abfd, 0, SEEK_SET) != 0)
- return NULL;
+ goto fail;
+
+ /* Call coff_object_p to read the COFF image. If this fails then the file
+ must be just a stub with no COFF data attached. */
+ bfd_cleanup cleanup = coff_object_p (abfd);
+ if (cleanup == NULL)
+ goto fail;
+ BFD_ASSERT (cleanup == _bfd_no_cleanup);
+
+ return go32exe_cleanup;
+
+ fail_format:
+ bfd_set_error (bfd_error_wrong_format);
+ fail:
+ go32exe_cleanup (abfd);
+ return NULL;
+}
+
+/* Write the stub to the output file, then call coff_write_object_contents. */
+
+static bfd_boolean
+go32exe_write_object_contents (bfd *abfd)
+{
+ const bfd_size_type pos = bfd_tell (abfd);
+ const bfd_size_type stubsize = coff_data (abfd)->stub_size;
+
+ BFD_ASSERT (stubsize != 0);
+
+ bfd_set_error (bfd_error_system_call);
- return coff_object_p (abfd);
+ /* Write the stub. */
+ abfd->origin = 0;
+ if (bfd_seek (abfd, 0, SEEK_SET) != 0)
+ return FALSE;
+ if (bfd_bwrite (coff_data (abfd)->stub, stubsize, abfd) != stubsize)
+ return FALSE;
+
+ /* Seek back to where we were. */
+ abfd->origin = stubsize;
+ if (bfd_seek (abfd, pos, SEEK_SET) != 0)
+ return FALSE;
+
+ return coff_write_object_contents (abfd);
+}
+
+/* mkobject hook. Called directly through bfd_set_format or via
+ coff_mkobject_hook etc from bfd_check_format. */
+
+static bfd_boolean
+go32exe_mkobject (bfd *abfd)
+{
+ coff_data_type *coff = NULL;
+ const bfd_size_type amt = sizeof (coff_data_type);
+
+ /* Don't output to an archive. */
+ if (abfd->my_archive != NULL)
+ return FALSE;
+
+ abfd->tdata.coff_obj_data = bfd_zalloc (abfd, amt);
+ if (abfd->tdata.coff_obj_data == NULL)
+ return FALSE;
+ coff = coff_data (abfd);
+ coff->symbols = NULL;
+ coff->conversion_table = NULL;
+ coff->raw_syments = NULL;
+ coff->relocbase = 0;
+ coff->local_toc_sym_map = 0;
+
+ go32exe_create_stub (abfd);
+ if (coff->stub == NULL)
+ {
+ bfd_release (abfd, coff);
+ return FALSE;
+ }
+ abfd->origin = coff->stub_size;
+
+/* make_abs_section(abfd);*/ /* ??? */
+
+ return TRUE;
}
projects / binutils-gdb.git / commitdiff