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- /* Convert COFF-format object file to BSD format.
- Used for converting the system libraries so GNU ld can link them.
- Copyright (C) 1988 Free Software Foundation, Inc.
-
- 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 1, 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., 675 Mass Ave, Cambridge, MA 02139, USA. */
-
- /*
- ** Robotussin - convert COFF format object files to BSD format.
- **
- ** written by Jeff Lewis, donated to the Free Software Foundation.
- **
- ** BUGS:
- ** Should do more to verify that the input COFF file meets our
- ** expectations.
- ** On machines where the structure of the COFF data in the file does not
- ** match the structure of the COFF data declared (when, for example
- ** sizeof (struct filhdr) != FILHSZ), this program will fail. (Don't
- ** ask me why this is ever allowed to come about). Accessor functions/
- ** macros that painstakingly extract the data out of the file and stuff
- ** it in the memory struct should be written to fix this on such machines.
- **
- ** CAVEATS:
- ** This program cannot claim correctness, however, it does appear
- ** to work on my fairly vanilla Sys5r2 machine. Someone with the time
- ** and a fine tooth comb (not to mention some documentation on COFF)
- ** should correct this!
- */
-
- #ifndef COFF_ENCAPSULATE
- #define COFF_ENCAPSULATE
- #endif
-
- /* Customization for particular machines. */
-
- #ifdef i386
- #define INPUT_MAGIC I386MAGIC
- #else /* not i386 */
- #if defined (m68k) || defined (mc68000)
- #define INPUT_MAGIC MC68MAGIC
- #endif
- #endif /* not i386 */
-
- #include <stdio.h>
- #include <varargs.h>
- #include <fcntl.h>
-
- #include "a.out.encap.h"
- #define N_ABSOLUTE N_ABS /* N_ABS will be redefined in syms.h */
- #undef N_ABS
-
- #include <filehdr.h>
- #include <aouthdr.h>
- #include <scnhdr.h>
- #include <syms.h>
- #include <reloc.h>
- /* Because of struct alignment on dwords sizeof (struct syment) is different
- than the syments stored in the file. Therefore, we must kludge: */
- #define sizeof_syment (SYMESZ)
- #define sizeof_reloc (RELSZ)
- #define sizeof_section (SCNHSZ)
- #define sizeof_coff_header (FILHSZ)
- /*
- Without the following, compiling this is a pain on a BSD4.3 Vax.
- Though that might not seem useful, the compatibility of byte order
- between a Vax and a 386 can come in handy for cross-debugging
- */
- #ifdef NO_VFPRINTF
- #define vfprintf(fp, format, ap) _doprnt (format, ap, fp)
- #endif /* not HAVE_VPRINTF */
-
- extern long lseek ();
- extern void exit ();
- extern char *memcpy ();
- extern int errno;
-
- void error (), sys_error ();
- static void reloc_segment ();
- char *mem_alloc ();
-
- int fd_in, fd_out; /* input and output file descriptors */
-
- struct filehdr coff_header; /* file header from the input file */
- struct exec bsd_header; /* file header for the output file */
-
- struct syment *coff_sym_listp; /* list of symbols from the input */
- int *symbol_map; /* mapping of input symbol #'s to
- output symbol numbers */
- char *text_and_data; /* space for text & data section data */
- char *relocations; /* space for output reloc entries */
- int verbose_flag; /* flag for debugging */
-
- struct scnhdr coff_text_header; /* COFF text section header */
- struct scnhdr coff_data_header; /* COFF data section header */
- struct scnhdr coff_bss_header; /* COFF bss section header */
- int text_sect_num; /* COFF section # for text */
- int data_sect_num; /* COFF section # for data */
- int bss_sect_num; /* COFF section # for bss */
-
- int
- main (argc, argv)
- int argc;
- char **argv;
- {
- int i, j;
- char *coff_string_table, *bsd_string_table;
- register char *pc, *pc2;
- int string_table_len;
- int symbol_count;
- struct scnhdr section;
- struct nlist name;
-
- if (argc < 3)
- error ("Usage: %s COFF-file BSD-file", argv[0]);
- if (argc > 3)
- verbose_flag = 1;
-
- fd_in = open (argv[1], O_RDONLY);
- if (fd_in < 0)
- sys_error ("can't open %s", argv[1]);
-
- fd_out = open (argv[2], O_WRONLY | O_CREAT | O_TRUNC, 0666);
- if (fd_out < 0)
- sys_error ("can't open %s", argv[2]);
-
- /*
- ** Read in the file header and all section headers searching
- ** for text, data and bss. We note the section #'s of these
- ** sections for use when examining symbols.
- */
-
- if (read (fd_in, &coff_header, sizeof_coff_header) != sizeof_coff_header)
- error ("can't read file header");
-
- if (coff_header.f_magic != INPUT_MAGIC)
- error ("bad magic number in coff file\n");
-
- lseek (fd_in, sizeof_coff_header + coff_header.f_opthdr, 0);
-
- for (i = 1; i <= coff_header.f_nscns; ++i)
- {
- if (read (fd_in, §ion, sizeof_section) != sizeof_section)
- error ("can't read section header #%d", i);
- if (strcmp (section.s_name, _TEXT) == 0)
- {
- text_sect_num = i;
- memcpy (&coff_text_header, §ion, sizeof section);
- }
- else if (strcmp (section.s_name, _DATA) == 0)
- {
- data_sect_num = i;
- memcpy (&coff_data_header, §ion, sizeof section);
- }
- else if (strcmp (section.s_name, _BSS) == 0)
- {
- bss_sect_num = i;
- memcpy (&coff_bss_header, §ion, sizeof section);
- }
- }
-
- #ifdef sun386
- /*
- The purpose of the following kludge is to cope with the discrepancy
- between coff_data_header.s_vaddr and coff_text_header.s_size; in a BSD
- object file, they are assumed equal. It should be ok to use
- coff_data_header.s_paddr, since it has no other apparent use.
- */
- coff_data_header.s_paddr = coff_text_header.s_size;
- coff_bss_header.s_paddr = coff_data_header.s_size + coff_text_header.s_size;
- #endif
-
- /*
- ** Pass1 thru the symbol table - count usable symbols and map
- ** old symbol #'s into new ones (as used by relocation
- ** info). We're only interested in keeping the kinds of symbols
- ** we'd expect to find in a BSD library object file: no debug
- ** symbols, file names, section definition symbols, etc.
- ** Section definition symbols are referenced by reloc entries
- ** in the COFF file, so we note their position with a negative
- ** symbol number indicating the section. -1 is used to flag
- ** symbols we're not interested in, yielding an unexpected error
- ** if we find any reloc entries referencing them.
- */
-
- coff_sym_listp =
- (struct syment *) mem_alloc (coff_header.f_nsyms * sizeof (struct syment));
- symbol_map = (int *) mem_alloc (coff_header.f_nsyms * sizeof *symbol_map);
- if (lseek (fd_in, coff_header.f_symptr, 0) < 0L)
- sys_error ("can't seek to COFF symbols");
- for (i = 0; i < coff_header.f_nsyms; ++i)
- {
- if (read (fd_in, coff_sym_listp + i, sizeof_syment) != sizeof_syment)
- error ("can't read COFF symbols");
- }
- symbol_count = 0;
- for (i = 0; i < coff_header.f_nsyms; ++i)
- {
- if (coff_sym_listp[i].n_scnum != N_DEBUG
- && coff_sym_listp[i].n_name[0] != '.'
- && coff_sym_listp[i].n_scnum != -1)
- {
- if (verbose_flag)
- printf ("map %d to %d\n", i, symbol_count);
- symbol_map[i] = symbol_count++;
- #ifdef sun386
- if (coff_sym_listp[i].n_scnum == data_sect_num)
- coff_sym_listp[i].n_value -=
- coff_data_header.s_vaddr - coff_data_header.s_paddr;
- else if (coff_sym_listp[i].n_scnum == bss_sect_num)
- coff_sym_listp[i].n_value -=
- coff_bss_header.s_vaddr - coff_bss_header.s_paddr;
- #endif
- }
- else
- {
- if (coff_sym_listp[i].n_sclass == C_STAT)
- {
- if (strcmp (coff_sym_listp[i].n_name, _TEXT) == 0)
- symbol_map[i] = -N_TEXT;
- else if (strcmp (coff_sym_listp[i].n_name, _DATA) == 0)
- symbol_map[i] = -N_DATA;
- else if (strcmp (coff_sym_listp[i].n_name, _BSS) == 0)
- symbol_map[i] = -N_BSS;
- else
- symbol_map[i] = -1;
- }
- else
- {
- symbol_map[i] = -1;
- }
- }
- /* skip auxillary entries */
- j = coff_sym_listp[i].n_numaux;
- if (j != 0)
- {
- if (j < 0)
- error ("invalid numaux");
- if (j != 1)
- fprintf (stderr, "unlikely numaux value\n");
- while (--j >= 0)
- ++i;
- }
- }
-
- /* now we know enough to write the output file header */
-
- N_SET_MAGIC (bsd_header, OMAGIC);
- bsd_header.a_text = coff_text_header.s_size;
- bsd_header.a_data = coff_data_header.s_size;
- bsd_header.a_bss = coff_bss_header.s_size;
- bsd_header.a_syms = symbol_count * sizeof (struct nlist);
- bsd_header.a_entry = 0;
- bsd_header.a_trsize = coff_text_header.s_nreloc * sizeof (struct relocation_info);
- bsd_header.a_drsize = coff_data_header.s_nreloc * sizeof (struct relocation_info);
- if (write (fd_out, &bsd_header, sizeof bsd_header) != sizeof bsd_header)
- sys_error ("can't write BSD header");
-
- /*
- ** Read in and save text and data sections - some data in
- ** these sections may need to be altered due to relocations.
- */
-
- text_and_data = (char *) mem_alloc (coff_text_header.s_size + coff_data_header.s_size);
- if (lseek (fd_in, coff_text_header.s_scnptr, 0) < 0L)
- sys_error ("can't seek to text section");
- if (read (fd_in, text_and_data, coff_text_header.s_size) != coff_text_header.s_size)
- error ("can't read text section");
- if (lseek (fd_in, coff_data_header.s_scnptr, 0) < 0L)
- sys_error ("can't seek to data section");
- if (read (fd_in, text_and_data + coff_text_header.s_size, coff_data_header.s_size) != coff_data_header.s_size)
- error ("can't read data section");
-
- /*
- ** Convert the relocation entries and do any text or data
- ** modifications necessary.
- */
-
- relocations = (char *) mem_alloc (bsd_header.a_trsize + bsd_header.a_drsize);
- reloc_segment (&coff_text_header, relocations);
- reloc_segment (&coff_data_header, relocations + bsd_header.a_trsize);
-
- if (write (fd_out, text_and_data, coff_text_header.s_size + coff_data_header.s_size)
- != coff_text_header.s_size + coff_data_header.s_size)
- sys_error ("can't write text and data sections");
- /* ZZ - are there any alignment considerations?? */
- if ((coff_text_header.s_size & 1) || (coff_data_header.s_size & 1))
- fprintf (stderr, "non-aligned text or data section\n");
- if (write (fd_out, relocations, bsd_header.a_trsize + bsd_header.a_drsize)
- != bsd_header.a_trsize + bsd_header.a_drsize)
- sys_error ("can't write relocation entries");
-
- /*
- ** Second pass thru the symbol table.
- ** a COFF symbol entry may contain up to 8 chars of symbol name
- ** in the entry itself - symbol names > 8 go into the string table,
- ** whereas the BSD entry puts all symbol names into the string
- ** table.
- */
-
- if (lseek (fd_in, coff_header.f_symptr + coff_header.f_nsyms * sizeof_syment, 0) < 0L)
- error ("can't seek to string table");
-
- i = read (fd_in, &string_table_len, sizeof string_table_len);
- if (i == sizeof string_table_len)
- {
- coff_string_table = mem_alloc (string_table_len);
- string_table_len -= sizeof string_table_len;
- i = read (fd_in, coff_string_table + sizeof string_table_len, string_table_len);
- if (i < 0)
- error ("can't read string table");
- if (i != string_table_len)
- error ("truncated string table - expected %d, got %d",
- string_table_len, i);
- }
- else
- {
- string_table_len = 0;
- }
- bsd_string_table = mem_alloc (string_table_len + coff_header.f_nsyms * (SYMNMLEN + 1));
- pc = bsd_string_table + sizeof string_table_len;
- for (i = 0; i < coff_header.f_nsyms; ++i)
- {
- if (coff_sym_listp[i].n_scnum != N_DEBUG
- && coff_sym_listp[i].n_name[0] != '.'
- && coff_sym_listp[i].n_scnum != -1)
- {
- if (coff_sym_listp[i].n_zeroes == 0)
- {
- j = pc - bsd_string_table;
- #ifndef nounderscore
- if (coff_sym_listp[i].n_sclass == C_EXT
- || coff_sym_listp[i].n_sclass == C_STAT)
- *pc++ = '_';
- #endif
- pc2 = coff_string_table + coff_sym_listp[i].n_offset;
- while (*pc++ = *pc2++)
- /* null */ ;
- name.n_un.n_strx = j;
- }
- else
- {
- pc2 = &coff_sym_listp[i].n_name[0];
- j = pc - bsd_string_table;
- #ifndef nounderscore
- if (coff_sym_listp[i].n_sclass == C_EXT
- || coff_sym_listp[i].n_sclass == C_STAT)
- *pc++ = '_';
- #endif
- {
- int x;
- for (x = 0; x < SYMNMLEN; x++)
- {
- if (*pc2 == 0)
- break;
- *pc++ = *pc2++;
- }
- *pc++ = 0;
- }
- name.n_un.n_strx = j;
- }
- switch (coff_sym_listp[i].n_scnum)
- {
- case N_ABS:
- name.n_type = N_ABSOLUTE;
- break;
- case N_UNDEF:
- name.n_type = N_UNDF;
- break;
- default:
- if (coff_sym_listp[i].n_scnum == text_sect_num)
- name.n_type = N_TEXT;
- else if (coff_sym_listp[i].n_scnum == data_sect_num)
- name.n_type = N_DATA;
- else if (coff_sym_listp[i].n_scnum == bss_sect_num)
- name.n_type = N_BSS;
- break;
- }
- if (coff_sym_listp[i].n_sclass == C_EXT)
- name.n_type |= N_EXT;
- name.n_other = 0;
- name.n_desc = 0;
- name.n_value = coff_sym_listp[i].n_value;
-
- if (write (fd_out, &name, sizeof name) != sizeof name)
- sys_error ("can't write symbol");
- }
- /* skip auxillary entries */
- j = coff_sym_listp[i].n_numaux;
- if (j != 0)
- {
- while (--j >= 0)
- ++i;
- }
- }
- i = *((int *) bsd_string_table) = pc - bsd_string_table;
- if (write (fd_out, bsd_string_table, i) != i)
- error ("can't write string table");
-
- close (fd_in);
- close (fd_out);
- exit (0);
- }
-
- /*
- ** Convert the relocation entries and do any text or data
- ** modifications necessary.
- */
-
- static void
- reloc_segment (section_headerp, reloc_infop)
- struct scnhdr *section_headerp;
- struct relocation_info *reloc_infop;
- {
- struct reloc coff_reloc;
- int i;
-
- if (lseek (fd_in, section_headerp->s_relptr, 0) < 0L)
- error ("can't seek to relocation entries");
- for (i = 0; i < section_headerp->s_nreloc; ++i)
- {
- if (read (fd_in, &coff_reloc, sizeof_reloc) != sizeof_reloc)
- error ("can't read relocation entry");
- #ifdef sun386
- coff_reloc.r_vaddr -=
- section_headerp->s_vaddr - section_headerp->s_paddr;
- #endif
- if (verbose_flag)
- printf ("vaddr = 0x%x, symndx = %d\n", coff_reloc.r_vaddr, coff_reloc.r_symndx);
- /*
- ** The reloc references a symbol declared common, thus the
- ** value of the symbol holds its size (in bytes). In COFF,
- ** apparently this info is also put into the binary -
- ** BSD doesn't like this, so we subtract it out.
- */
- if (coff_sym_listp[coff_reloc.r_symndx].n_scnum == N_UNDEF)
- {
- if (coff_sym_listp[coff_reloc.r_symndx].n_value != 0)
- {
- if (verbose_flag)
- printf ("adjust common 0x%x (%d)\n",
- coff_sym_listp[coff_reloc.r_symndx].n_value,
- coff_sym_listp[coff_reloc.r_symndx].n_value);
- switch (coff_reloc.r_type)
- {
- case R_RELBYTE:
- *((char *) (text_and_data + coff_reloc.r_vaddr))
- -= coff_sym_listp[coff_reloc.r_symndx].n_value;
- break;
- case R_RELWORD:
- *((short *) (text_and_data + coff_reloc.r_vaddr))
- -= coff_sym_listp[coff_reloc.r_symndx].n_value;
- break;
- case R_RELLONG:
- case R_DIR32: /* these are the only two that really show up */
- case R_PCRLONG:
- *((int *) (text_and_data + coff_reloc.r_vaddr))
- -= coff_sym_listp[coff_reloc.r_symndx].n_value;
- break;
- default:
- error ("unknown relocation type 0%o", coff_reloc.r_type);
- }
- }
- }
- /*
- ** >= 0 means its an extern - value is the output symbol #.
- ** < 0 means its an intern - value is N_TEXT, N_DATA or N_BSS.
- */
- if (symbol_map[coff_reloc.r_symndx] >= 0)
- {
- reloc_infop->r_symbolnum = symbol_map[coff_reloc.r_symndx];
- reloc_infop->r_extern = 1;
- }
- else
- {
- if (symbol_map[coff_reloc.r_symndx] == -1)
- error ("Oops! possible bug - reloc reference to ignored symbol");
- #ifdef sun386
- {
- int offset=0;
- switch (-symbol_map[coff_reloc.r_symndx])
- {
- case N_DATA:
- offset = coff_data_header.s_vaddr - coff_data_header.s_paddr;
- break;
- case N_BSS:
- offset = coff_bss_header.s_vaddr - coff_bss_header.s_paddr;
- break;
- }
- switch (coff_reloc.r_type)
- {
- case R_RELBYTE:
- *((char *) (text_and_data + coff_reloc.r_vaddr)) -= offset;
- break;
- case R_RELWORD:
- *((short *) (text_and_data + coff_reloc.r_vaddr)) -= offset;
- break;
- case R_RELLONG:
- case R_DIR32:
- case R_PCRLONG:
- *((int *) (text_and_data + coff_reloc.r_vaddr)) -= offset;
- break;
- default:
- error ("unknown relocation type 0%o", coff_reloc.r_type);
- }
- }
- #endif
- reloc_infop->r_symbolnum = -symbol_map[coff_reloc.r_symndx];
- reloc_infop->r_extern = 0;
- }
- /*
- ** COFF address includes the section address - BSD doesn't, so
- ** subtract it out.
- */
- #ifdef sun386
- coff_reloc.r_vaddr +=
- section_headerp->s_vaddr - section_headerp->s_paddr;
- #endif
- reloc_infop->r_address = coff_reloc.r_vaddr - section_headerp->s_vaddr;
- switch (coff_reloc.r_type)
- {
- case R_PCRLONG:
- reloc_infop->r_pcrel = 1;
- reloc_infop->r_length = 2; /* 4 bytes */
- break;
- case R_DIR32:
- case R_RELLONG:
- reloc_infop->r_pcrel = 0;
- reloc_infop->r_length = 2;
- break;
- default:
- error ("can't handle coff reloction type 0%o", coff_reloc.r_type);
- }
-
- if (verbose_flag)
- printf ("reloc: addr = 0x%x, synum = %d\n",
- reloc_infop->r_address, reloc_infop->r_symbolnum);
- reloc_infop->r_pad = 0;
- ++reloc_infop;
- }
- }
-
- void
- error (format, va_alist)
- char *format;
- va_dcl
- {
- va_list args;
-
- va_start (args);
- fprintf (stderr, "robotussin: ");
- vfprintf (stderr, format, args);
- putc ('\n', stderr);
- va_end (args);
- exit (1);
- }
-
- extern char *sys_errlist[];
- extern int errno;
-
- void
- sys_error (format, va_alist)
- char *format;
- va_dcl
- {
- va_list args;
-
- va_start (args);
- fprintf (stderr, "robotussin: ");
- vfprintf (stderr, format, args);
- fprintf (stderr, ": %s\n", sys_errlist[errno]);
- va_end (args);
- exit (1);
- }
-
- extern char *malloc ();
-
- char *
- mem_alloc (size)
- int size;
- {
- char *pc;
-
- if ((pc = malloc (size)) == NULL)
- error ("memory exhausted!");
- return pc;
- }
-
- /* end */
-