diff options
Diffstat (limited to 'binutils-2.25/bfd/coff-stgo32.c')
| -rw-r--r-- | binutils-2.25/bfd/coff-stgo32.c | 425 |
1 files changed, 425 insertions, 0 deletions
diff --git a/binutils-2.25/bfd/coff-stgo32.c b/binutils-2.25/bfd/coff-stgo32.c new file mode 100644 index 00000000..882ddd2f --- /dev/null +++ b/binutils-2.25/bfd/coff-stgo32.c @@ -0,0 +1,425 @@ +/* BFD back-end for Intel 386 COFF files (DJGPP variant with a stub). + Copyright 1997, 1998, 1999, 2000, 2001, 2002, 2005, 2006, 2007, 2009, + 2011, 2012 Free Software Foundation, Inc. + Written by Robert Hoehne. + + This file is part of BFD, the Binary File Descriptor library. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, + MA 02110-1301, USA. */ + +/* This file handles now also stubbed coff images. The stub is a small + 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. */ + +#define TARGET_SYM go32stubbedcoff_vec +#define TARGET_NAME "coff-go32-exe" +#define TARGET_UNDERSCORE '_' +#define COFF_GO32_EXE +#define COFF_LONG_SECTION_NAMES +#define COFF_SUPPORT_GNU_LINKONCE +#define COFF_LONG_FILENAMES + +#define COFF_SECTION_ALIGNMENT_ENTRIES \ +{ COFF_SECTION_NAME_EXACT_MATCH (".data"), \ + COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 4 }, \ +{ COFF_SECTION_NAME_EXACT_MATCH (".text"), \ + COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 4 }, \ +{ COFF_SECTION_NAME_PARTIAL_MATCH (".debug"), \ + COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 0 }, \ +{ COFF_SECTION_NAME_PARTIAL_MATCH (".gnu.linkonce.wi"), \ + COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 0 } + +#include "sysdep.h" +#include "bfd.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 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 const bfd_target *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 + +#include "coff-i386.c" + +/* This macro is used, because I cannot assume the endianness of the + host system. */ +#define _H(index) (H_GET_16 (abfd, (header + index * 2))) + +/* 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] = +{ +#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); + } +} + +/* That's the function, which creates the stub. There are + different cases from where the stub is taken. + At first the environment variable $(GO32STUB) is checked and then + $(STUB) if it was not set. + If it exists and points to a valid stub the stub is taken from + that file. This file can be also a whole executable file, because + the stub is computed from the exe information at the start of that + file. + + If there was any error, the standard stub (compiled in this file) + is taken. */ + +static void +create_go32_stub (bfd *abfd) +{ + /* Do it only once. */ + if (coff_data (abfd)->go32stub == NULL) + { + char *stub; + struct stat st; + int f; + unsigned char header[10]; + char magic[8]; + unsigned long coff_start; + long exe_start; + + /* Check at first the environment variable $(GO32STUB). */ + stub = getenv ("GO32STUB"); + /* Now check the environment variable $(STUB). */ + if (stub == NULL) + stub = getenv ("STUB"); + if (stub == NULL) + goto stub_end; + if (stat (stub, &st) != 0) + goto stub_end; +#ifdef O_BINARY + f = open (stub, O_RDONLY | O_BINARY); +#else + f = open (stub, O_RDONLY); +#endif + if (f < 0) + goto stub_end; + if (read (f, &header, sizeof (header)) < 0) + { + close (f); + goto stub_end; + } + if (_H (0) != 0x5a4d) /* It is not an exe file. */ + { + close (f); + goto stub_end; + } + /* Compute the size of the stub (it is every thing up + to the beginning of the coff image). */ + coff_start = (long) _H (2) * 512L; + 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) + { + close (f); + goto stub_end; + } + if (read (f, &magic, 8) != 8) + { + close (f); + goto stub_end; + } + if (! CONST_STRNEQ (magic, "go32stub")) + { + close (f); + 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) + { + close (f); + return; + } + lseek (f, 0L, SEEK_SET); + if ((unsigned long) read (f, coff_data (abfd)->go32stub, coff_start) + != coff_start) + { + bfd_release (abfd, coff_data (abfd)->go32stub); + coff_data (abfd)->go32stub = NULL; + } + close (f); + } +stub_end: + /* There was something wrong above, so use now the standard builtin + stub. */ + if (coff_data (abfd)->go32stub == NULL) + { + coff_data (abfd)->go32stub + = bfd_alloc (abfd, (bfd_size_type) GO32_STUBSIZE); + if (coff_data (abfd)->go32stub == NULL) + return; + memcpy (coff_data (abfd)->go32stub, stub_bytes, GO32_STUBSIZE); + } +} + +/* If ibfd was a stubbed coff image, copy the stub from that bfd + to the new obfd. */ + +static bfd_boolean +go32_stubbed_coff_bfd_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; + + /* 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); + + /* Now copy the stub. */ + if (coff_data (obfd)->go32stub != NULL) + memcpy (coff_data (obfd)->go32stub, coff_data (ibfd)->go32stub, + GO32_STUBSIZE); + + return TRUE; +} + +/* coff_object_p only checks 2 bytes F_MAGIC at GO32_STUBSIZE inside the file + which is too fragile. */ + +static const bfd_target * +go32_check_format (bfd *abfd) +{ + char mz[2]; + + if (bfd_bread (mz, 2, abfd) != 2 || mz[0] != 'M' || mz[1] != 'Z') + { + bfd_set_error (bfd_error_wrong_format); + return NULL; + } + + if (bfd_seek (abfd, 0, SEEK_SET) != 0) + return NULL; + + return coff_object_p (abfd); +} |