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elf2ecoff.c revision 1.21
      1 /*	$NetBSD: elf2ecoff.c,v 1.21 2003/10/27 00:12:43 lukem Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1997 Jonathan Stone
      5  *    All rights reserved.
      6  * Copyright (c) 1995
      7  *	Ted Lemon (hereinafter referred to as the author)
      8  *
      9  * Redistribution and use in source and binary forms, with or without
     10  * modification, are permitted provided that the following conditions
     11  * are met:
     12  * 1. Redistributions of source code must retain the above copyright
     13  *    notice, this list of conditions and the following disclaimer.
     14  * 2. Redistributions in binary form must reproduce the above copyright
     15  *    notice, this list of conditions and the following disclaimer in the
     16  *    documentation and/or other materials provided with the distribution.
     17  * 3. The name of the author may not be used to endorse or promote products
     18  *    derived from this software without specific prior written permission.
     19  *
     20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND
     21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE
     24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     30  * SUCH DAMAGE.
     31  */
     32 
     33 /* elf2ecoff.c
     34 
     35    This program converts an elf executable to an ECOFF executable.
     36    No symbol table is retained.   This is useful primarily in building
     37    net-bootable kernels for machines (e.g., DECstation and Alpha) which
     38    only support the ECOFF object file format. */
     39 
     40 #if HAVE_NBTOOL_CONFIG_H
     41 #include "nbtool_config.h"
     42 #endif
     43 
     44 #include <sys/types.h>
     45 #include <err.h>
     46 #include <errno.h>
     47 #include <fcntl.h>
     48 #include <unistd.h>
     49 #include <sys/exec_elf.h>
     50 #include <stdio.h>
     51 #include <sys/exec_ecoff.h>
     52 #include <stdlib.h>
     53 #include <string.h>
     54 #include <limits.h>
     55 
     56 #define	ISLAST(p)	(p->n_un.n_name == 0 || p->n_un.n_name[0] == 0)
     57 
     58 struct sect {
     59 	unsigned long vaddr;
     60 	unsigned long len;
     61 };
     62 
     63 struct elf_syms {
     64 	int     nsymbols;
     65 	Elf32_Sym *elf_syms;
     66 	off_t   stringsize;
     67 	char   *stringtab;
     68 };
     69 
     70 struct ecoff_syms {
     71 	int     nsymbols;
     72 	struct ecoff_extsym *ecoff_syms;
     73 	off_t   stringsize;
     74 	char   *stringtab;
     75 };
     76 
     77 int     debug = 0;
     78 
     79 int     phcmp(Elf32_Phdr * h1, Elf32_Phdr * h2);
     80 
     81 
     82 char   *saveRead(int file, off_t offset, off_t len, char *name);
     83 void    safewrite(int outfile, void *buf, off_t len, const char *msg);
     84 void    copy(int, int, off_t, off_t);
     85 void    combine(struct sect * base, struct sect * new, int paddable);
     86 void    translate_syms(struct elf_syms *, struct ecoff_syms *);
     87 void
     88 elf_symbol_table_to_ecoff(int out, int in,
     89     struct ecoff_exechdr * ep,
     90     off_t symoff, off_t symsize,
     91     off_t stroff, off_t strsize);
     92 
     93 
     94 int
     95 make_ecoff_section_hdrs(struct ecoff_exechdr * ep,
     96     struct ecoff_scnhdr * esecs);
     97 
     98 void
     99 write_ecoff_symhdr(int outfile, struct ecoff_exechdr * ep,
    100     struct ecoff_symhdr * symhdrp,
    101     long nesyms, long extsymoff, long extstroff,
    102     long strsize);
    103 
    104 void    pad16(int fd, int size, const char *msg);
    105 void	bswap32_region(u_int32_t* , int);
    106 
    107 int    *symTypeTable;
    108 int	needswap;
    109 
    110 
    111 
    112 
    113 void
    114 elf_read_syms(struct elf_syms * elfsymsp, int infile,
    115     off_t symoff, off_t symsize, off_t stroff, off_t strsize);
    116 
    117 
    118 int
    119 main(int argc, char **argv, char **envp)
    120 {
    121 	Elf32_Ehdr ex;
    122 	Elf32_Phdr *ph;
    123 	Elf32_Shdr *sh;
    124 	char   *shstrtab;
    125 	int     strtabix, symtabix;
    126 	int     i, pad;
    127 	struct sect text, data, bss;	/* a.out-compatible sections */
    128 	struct sect rdata, sdata, sbss;	/* ECOFF-only sections */
    129 
    130 	struct ecoff_exechdr ep;
    131 	struct ecoff_scnhdr esecs[6];
    132 	struct ecoff_symhdr symhdr;
    133 
    134 	int     infile, outfile;
    135 	unsigned long cur_vma = ULONG_MAX;
    136 	int     symflag = 0;
    137 	int     nsecs = 0;
    138 	int	mipsel;
    139 
    140 
    141 	text.len = data.len = bss.len = 0;
    142 	text.vaddr = data.vaddr = bss.vaddr = 0;
    143 
    144 	rdata.len = sdata.len = sbss.len = 0;
    145 	rdata.vaddr = sdata.vaddr = sbss.vaddr = 0;
    146 
    147 	/* Check args... */
    148 	if (argc < 3 || argc > 4) {
    149 usage:
    150 		fprintf(stderr,
    151 		    "usage: elf2ecoff <elf executable> <ECOFF executable> [-s]\n");
    152 		exit(1);
    153 	}
    154 	if (argc == 4) {
    155 		if (strcmp(argv[3], "-s"))
    156 			goto usage;
    157 		symflag = 1;
    158 	}
    159 	/* Try the input file... */
    160 	if ((infile = open(argv[1], O_RDONLY)) < 0) {
    161 		fprintf(stderr, "Can't open %s for read: %s\n",
    162 		    argv[1], strerror(errno));
    163 		exit(1);
    164 	}
    165 	/* Read the header, which is at the beginning of the file... */
    166 	i = read(infile, &ex, sizeof ex);
    167 	if (i != sizeof ex) {
    168 		fprintf(stderr, "ex: %s: %s.\n",
    169 		    argv[1], i ? strerror(errno) : "End of file reached");
    170 		exit(1);
    171 	}
    172 	if (ex.e_ident[EI_DATA] == ELFDATA2LSB)
    173 		mipsel = 1;
    174 	else if (ex.e_ident[EI_DATA] == ELFDATA2MSB)
    175 		mipsel = 0;
    176 	else {
    177 		fprintf(stderr, "invalid ELF byte order %d\n",
    178 		    ex.e_ident[EI_DATA]);
    179 		exit(1);
    180 	}
    181 #if BYTE_ORDER == BIG_ENDIAN
    182 	if (mipsel)
    183 		needswap = 1;
    184 	else
    185 		needswap = 0;
    186 #elif BYTE_ORDER == LITTLE_ENDIAN
    187 	if (mipsel)
    188 		needswap = 0;
    189 	else
    190 		needswap = 1;
    191 #else
    192 #error "unknown endian"
    193 #endif
    194 
    195 	if (needswap) {
    196 		ex.e_type	= bswap16(ex.e_type);
    197 		ex.e_machine	= bswap16(ex.e_machine);
    198 		ex.e_version	= bswap32(ex.e_version);
    199 		ex.e_entry 	= bswap32(ex.e_entry);
    200 		ex.e_phoff	= bswap32(ex.e_phoff);
    201 		ex.e_shoff	= bswap32(ex.e_shoff);
    202 		ex.e_flags	= bswap32(ex.e_flags);
    203 		ex.e_ehsize	= bswap16(ex.e_ehsize);
    204 		ex.e_phentsize	= bswap16(ex.e_phentsize);
    205 		ex.e_phnum	= bswap16(ex.e_phnum);
    206 		ex.e_shentsize	= bswap16(ex.e_shentsize);
    207 		ex.e_shnum	= bswap16(ex.e_shnum);
    208 		ex.e_shstrndx	= bswap16(ex.e_shstrndx);
    209 	}
    210 
    211 	/* Read the program headers... */
    212 	ph = (Elf32_Phdr *) saveRead(infile, ex.e_phoff,
    213 	    ex.e_phnum * sizeof(Elf32_Phdr), "ph");
    214 	if (needswap)
    215 		bswap32_region((u_int32_t*)ph, sizeof(Elf32_Phdr) * ex.e_phnum);
    216 	/* Read the section headers... */
    217 	sh = (Elf32_Shdr *) saveRead(infile, ex.e_shoff,
    218 	    ex.e_shnum * sizeof(Elf32_Shdr), "sh");
    219 	if (needswap)
    220 		bswap32_region((u_int32_t*)sh, sizeof(Elf32_Shdr) * ex.e_shnum);
    221 
    222 	/* Read in the section string table. */
    223 	shstrtab = saveRead(infile, sh[ex.e_shstrndx].sh_offset,
    224 	    sh[ex.e_shstrndx].sh_size, "shstrtab");
    225 
    226 
    227 	/* Look for the symbol table and string table... Also map section
    228 	 * indices to symbol types for a.out */
    229 	symtabix = 0;
    230 	strtabix = 0;
    231 	for (i = 0; i < ex.e_shnum; i++) {
    232 		char   *name = shstrtab + sh[i].sh_name;
    233 		if (!strcmp(name, ".symtab"))
    234 			symtabix = i;
    235 		else
    236 			if (!strcmp(name, ".strtab"))
    237 				strtabix = i;
    238 
    239 	}
    240 
    241 	/* Figure out if we can cram the program header into an ECOFF
    242 	 * header...  Basically, we can't handle anything but loadable
    243 	 * segments, but we can ignore some kinds of segments.  We can't
    244 	 * handle holes in the address space.  Segments may be out of order,
    245 	 * so we sort them first. */
    246 
    247 	qsort(ph, ex.e_phnum, sizeof(Elf32_Phdr),
    248 	    (int (*) (const void *, const void *)) phcmp);
    249 
    250 	for (i = 0; i < ex.e_phnum; i++) {
    251 		/* Section types we can ignore... */
    252 		if (ph[i].p_type == PT_NULL || ph[i].p_type == PT_NOTE ||
    253 		    ph[i].p_type == PT_PHDR ||
    254 		    ph[i].p_type == PT_MIPS_REGINFO) {
    255 
    256 			if (debug) {
    257 				fprintf(stderr, "  skipping PH %d type %d flags 0x%x\n",
    258 				    i, ph[i].p_type, ph[i].p_flags);
    259 			}
    260 			continue;
    261 		}
    262 		/* Section types we can't handle... */
    263 		else
    264 			if (ph[i].p_type != PT_LOAD) {
    265 				fprintf(stderr, "Program header %d type %d can't be converted.\n",
    266 				    i, ph[i].p_type);
    267 				exit(1);
    268 			}
    269 		/* Writable (data) segment? */
    270 		if (ph[i].p_flags & PF_W) {
    271 			struct sect ndata, nbss;
    272 
    273 			ndata.vaddr = ph[i].p_vaddr;
    274 			ndata.len = ph[i].p_filesz;
    275 			nbss.vaddr = ph[i].p_vaddr + ph[i].p_filesz;
    276 			nbss.len = ph[i].p_memsz - ph[i].p_filesz;
    277 
    278 			if (debug) {
    279 				fprintf(stderr,
    280 				    "  combinining PH %d type %d flags 0x%x with data, ndata = %ld, nbss =%ld\n", i, ph[i].p_type, ph[i].p_flags, ndata.len, nbss.len);
    281 			}
    282 			combine(&data, &ndata, 0);
    283 			combine(&bss, &nbss, 1);
    284 		} else {
    285 			struct sect ntxt;
    286 
    287 			ntxt.vaddr = ph[i].p_vaddr;
    288 			ntxt.len = ph[i].p_filesz;
    289 			if (debug) {
    290 
    291 				fprintf(stderr,
    292 				    "  combinining PH %d type %d flags 0x%x with text, len = %ld\n",
    293 				    i, ph[i].p_type, ph[i].p_flags, ntxt.len);
    294 			}
    295 			combine(&text, &ntxt, 0);
    296 		}
    297 		/* Remember the lowest segment start address. */
    298 		if (ph[i].p_vaddr < cur_vma)
    299 			cur_vma = ph[i].p_vaddr;
    300 	}
    301 
    302 	/* Sections must be in order to be converted... */
    303 	if (text.vaddr > data.vaddr || data.vaddr > bss.vaddr ||
    304 	    text.vaddr + text.len > data.vaddr || data.vaddr + data.len > bss.vaddr) {
    305 		fprintf(stderr, "Sections ordering prevents a.out conversion.\n");
    306 		exit(1);
    307 	}
    308 	/* If there's a data section but no text section, then the loader
    309 	 * combined everything into one section.   That needs to be the text
    310 	 * section, so just make the data section zero length following text. */
    311 	if (data.len && !text.len) {
    312 		text = data;
    313 		data.vaddr = text.vaddr + text.len;
    314 		data.len = 0;
    315 	}
    316 	/* If there is a gap between text and data, we'll fill it when we copy
    317 	 * the data, so update the length of the text segment as represented
    318 	 * in a.out to reflect that, since a.out doesn't allow gaps in the
    319 	 * program address space. */
    320 	if (text.vaddr + text.len < data.vaddr)
    321 		text.len = data.vaddr - text.vaddr;
    322 
    323 	/* We now have enough information to cons up an a.out header... */
    324 	ep.a.magic = ECOFF_OMAGIC;
    325 	ep.a.vstamp = 2 * 256 + 10;	/* compatible with version 2.10 */
    326 	ep.a.tsize = text.len;
    327 	ep.a.dsize = data.len;
    328 	ep.a.bsize = bss.len;
    329 	ep.a.entry = ex.e_entry;
    330 	ep.a.text_start = text.vaddr;
    331 	ep.a.data_start = data.vaddr;
    332 	ep.a.bss_start = bss.vaddr;
    333 	ep.a.gprmask = 0xf3fffffe;
    334 	memset(&ep.a.cprmask, 0, sizeof ep.a.cprmask);
    335 	ep.a.gp_value = 0;	/* unused. */
    336 
    337 	if (mipsel)
    338 		ep.f.f_magic = ECOFF_MAGIC_MIPSEL;
    339 	else
    340 		ep.f.f_magic = ECOFF_MAGIC_MIPSEB;
    341 
    342 	ep.f.f_nscns = 6;
    343 	ep.f.f_timdat = 0;	/* bogus */
    344 	ep.f.f_symptr = 0;
    345 	ep.f.f_nsyms = sizeof(struct ecoff_symhdr);
    346 	ep.f.f_opthdr = sizeof ep.a;
    347 	ep.f.f_flags = 0x100f;	/* Stripped, not sharable. */
    348 
    349 	memset(esecs, 0, sizeof(esecs));
    350 
    351 	/* Make  ECOFF section headers, with empty stubs for
    352 	 * .rdata/.sdata/.sbss. */
    353 	make_ecoff_section_hdrs(&ep, esecs);
    354 
    355 	nsecs = ep.f.f_nscns;
    356 
    357 	if (needswap) {
    358 		ep.f.f_magic	= bswap16(ep.f.f_magic);
    359 		ep.f.f_nscns	= bswap16(ep.f.f_nscns);
    360 		ep.f.f_timdat	= bswap32(ep.f.f_timdat);
    361 		ep.f.f_symptr	= bswap32(ep.f.f_symptr);
    362 		ep.f.f_nsyms	= bswap32(ep.f.f_nsyms);
    363 		ep.f.f_opthdr	= bswap16(ep.f.f_opthdr);
    364 		ep.f.f_flags	= bswap16(ep.f.f_flags);
    365 		ep.a.magic	= bswap16(ep.a.magic);
    366 		ep.a.vstamp	= bswap16(ep.a.vstamp);
    367 		ep.a.tsize	= bswap32(ep.a.tsize);
    368 		ep.a.dsize	= bswap32(ep.a.dsize);
    369 		ep.a.bsize	= bswap32(ep.a.bsize);
    370 		ep.a.entry	= bswap32(ep.a.entry);
    371 		ep.a.text_start	= bswap32(ep.a.text_start);
    372 		ep.a.data_start	= bswap32(ep.a.data_start);
    373 		ep.a.bss_start	= bswap32(ep.a.bss_start);
    374 		ep.a.gprmask	= bswap32(ep.a.gprmask);
    375 		bswap32_region((u_int32_t*)ep.a.cprmask, sizeof(ep.a.cprmask));
    376 		ep.a.gp_value	= bswap32(ep.a.gp_value);
    377 		for (i = 0; i < sizeof(esecs) / sizeof(esecs[0]); i++) {
    378 			esecs[i].s_paddr	= bswap32(esecs[i].s_paddr);
    379 			esecs[i].s_vaddr	= bswap32(esecs[i].s_vaddr);
    380 			esecs[i].s_size 	= bswap32(esecs[i].s_size);
    381 			esecs[i].s_scnptr	= bswap32(esecs[i].s_scnptr);
    382 			esecs[i].s_relptr	= bswap32(esecs[i].s_relptr);
    383 			esecs[i].s_lnnoptr	= bswap32(esecs[i].s_lnnoptr);
    384 			esecs[i].s_nreloc	= bswap16(esecs[i].s_nreloc);
    385 			esecs[i].s_nlnno	= bswap16(esecs[i].s_nlnno);
    386 			esecs[i].s_flags	= bswap32(esecs[i].s_flags);
    387 		}
    388 	}
    389 
    390 	/* Make the output file... */
    391 	if ((outfile = open(argv[2], O_WRONLY | O_CREAT, 0777)) < 0) {
    392 		fprintf(stderr, "Unable to create %s: %s\n", argv[2], strerror(errno));
    393 		exit(1);
    394 	}
    395 	/* Truncate file... */
    396 	if (ftruncate(outfile, 0)) {
    397 		warn("ftruncate %s", argv[2]);
    398 	}
    399 	/* Write the headers... */
    400 	safewrite(outfile, &ep.f, sizeof(ep.f), "ep.f: write: %s\n");
    401 	if (debug)
    402 		fprintf(stderr, "wrote %d byte file header.\n", sizeof(ep.f));
    403 
    404 	safewrite(outfile, &ep.a, sizeof(ep.a), "ep.a: write: %s\n");
    405 	if (debug)
    406 		fprintf(stderr, "wrote %d byte a.out header.\n", sizeof(ep.a));
    407 
    408 	safewrite(outfile, &esecs, sizeof(esecs[0]) * nsecs,
    409 	    "esecs: write: %s\n");
    410 	if (debug)
    411 		fprintf(stderr, "wrote %d bytes of section headers.\n",
    412 		    sizeof(esecs[0]) * nsecs);
    413 
    414 
    415 	pad = ((sizeof ep.f + sizeof ep.a + sizeof esecs) & 15);
    416 	if (pad) {
    417 		pad = 16 - pad;
    418 		pad16(outfile, pad, "ipad: write: %s\n");
    419 		if (debug)
    420 			fprintf(stderr, "wrote %d byte pad.\n", pad);
    421 	}
    422 	/* Copy the loadable sections.   Zero-fill any gaps less than 64k;
    423 	 * complain about any zero-filling, and die if we're asked to
    424 	 * zero-fill more than 64k. */
    425 	for (i = 0; i < ex.e_phnum; i++) {
    426 		/* Unprocessable sections were handled above, so just verify
    427 		 * that the section can be loaded before copying. */
    428 		if (ph[i].p_type == PT_LOAD && ph[i].p_filesz) {
    429 			if (cur_vma != ph[i].p_vaddr) {
    430 				unsigned long gap = ph[i].p_vaddr - cur_vma;
    431 				char    obuf[1024];
    432 				if (gap > 65536) {
    433 					fprintf(stderr, "Intersegment gap (%ld bytes) too large.\n",
    434 					    gap);
    435 					exit(1);
    436 				}
    437 				if (debug)
    438 					fprintf(stderr, "Warning: %ld byte intersegment gap.\n", gap);
    439 				memset(obuf, 0, sizeof obuf);
    440 				while (gap) {
    441 					int     count = write(outfile, obuf, (gap > sizeof obuf
    442 						? sizeof obuf : gap));
    443 					if (count < 0) {
    444 						fprintf(stderr, "Error writing gap: %s\n",
    445 						    strerror(errno));
    446 						exit(1);
    447 					}
    448 					gap -= count;
    449 				}
    450 			}
    451 			if (debug)
    452 				fprintf(stderr, "writing %d bytes...\n", ph[i].p_filesz);
    453 			copy(outfile, infile, ph[i].p_offset, ph[i].p_filesz);
    454 			cur_vma = ph[i].p_vaddr + ph[i].p_filesz;
    455 		}
    456 	}
    457 
    458 
    459 	if (debug)
    460 		fprintf(stderr, "writing syms at offset 0x%lx\n",
    461 		    (u_long) ep.f.f_symptr + sizeof(symhdr));
    462 
    463 	/* Copy and translate the symbol table... */
    464 	elf_symbol_table_to_ecoff(outfile, infile, &ep,
    465 	    sh[symtabix].sh_offset, sh[symtabix].sh_size,
    466 	    sh[strtabix].sh_offset, sh[strtabix].sh_size);
    467 
    468 	/*
    469          * Write a page of padding for boot PROMS that read entire pages.
    470          * Without this, they may attempt to read past the end of the
    471          * data section, incur an error, and refuse to boot.
    472          */
    473 	{
    474 		char    obuf[4096];
    475 		memset(obuf, 0, sizeof obuf);
    476 		if (write(outfile, obuf, sizeof(obuf)) != sizeof(obuf)) {
    477 			fprintf(stderr, "Error writing PROM padding: %s\n",
    478 			    strerror(errno));
    479 			exit(1);
    480 		}
    481 	}
    482 
    483 	/* Looks like we won... */
    484 	exit(0);
    485 }
    486 
    487 void
    488 copy(out, in, offset, size)
    489 	int     out, in;
    490 	off_t   offset, size;
    491 {
    492 	char    ibuf[4096];
    493 	int     remaining, cur, count;
    494 
    495 	/* Go to the start of the ELF symbol table... */
    496 	if (lseek(in, offset, SEEK_SET) < 0) {
    497 		perror("copy: lseek");
    498 		exit(1);
    499 	}
    500 	remaining = size;
    501 	while (remaining) {
    502 		cur = remaining;
    503 		if (cur > sizeof ibuf)
    504 			cur = sizeof ibuf;
    505 		remaining -= cur;
    506 		if ((count = read(in, ibuf, cur)) != cur) {
    507 			fprintf(stderr, "copy: read: %s\n",
    508 			    count ? strerror(errno) : "premature end of file");
    509 			exit(1);
    510 		}
    511 		safewrite(out, ibuf, cur, "copy: write: %s\n");
    512 	}
    513 }
    514 /* Combine two segments, which must be contiguous.   If pad is true, it's
    515    okay for there to be padding between. */
    516 void
    517 combine(base, new, pad)
    518 	struct sect *base, *new;
    519 	int     pad;
    520 {
    521 	if (!base->len)
    522 		*base = *new;
    523 	else
    524 		if (new->len) {
    525 			if (base->vaddr + base->len != new->vaddr) {
    526 				if (pad)
    527 					base->len = new->vaddr - base->vaddr;
    528 				else {
    529 					fprintf(stderr,
    530 					    "Non-contiguous data can't be converted.\n");
    531 					exit(1);
    532 				}
    533 			}
    534 			base->len += new->len;
    535 		}
    536 }
    537 
    538 int
    539 phcmp(h1, h2)
    540 	Elf32_Phdr *h1, *h2;
    541 {
    542 	if (h1->p_vaddr > h2->p_vaddr)
    543 		return 1;
    544 	else
    545 		if (h1->p_vaddr < h2->p_vaddr)
    546 			return -1;
    547 		else
    548 			return 0;
    549 }
    550 
    551 char
    552        *
    553 saveRead(int file, off_t offset, off_t len, char *name)
    554 {
    555 	char   *tmp;
    556 	int     count;
    557 	off_t   off;
    558 	if ((off = lseek(file, offset, SEEK_SET)) < 0) {
    559 		fprintf(stderr, "%s: fseek: %s\n", name, strerror(errno));
    560 		exit(1);
    561 	}
    562 	if (!(tmp = (char *) malloc(len))) {
    563 		fprintf(stderr, "%s: Can't allocate %ld bytes.\n", name, (long) len);
    564 		exit(1);
    565 	}
    566 	count = read(file, tmp, len);
    567 	if (count != len) {
    568 		fprintf(stderr, "%s: read: %s.\n",
    569 		    name, count ? strerror(errno) : "End of file reached");
    570 		exit(1);
    571 	}
    572 	return tmp;
    573 }
    574 
    575 void
    576 safewrite(int outfile, void *buf, off_t len, const char *msg)
    577 {
    578 	int     written;
    579 	written = write(outfile, (char *) buf, len);
    580 	if (written != len) {
    581 		fprintf(stderr, msg, strerror(errno));
    582 		exit(1);
    583 	}
    584 }
    585 
    586 
    587 /*
    588  * Output only three ECOFF sections, corresponding to ELF psecs
    589  * for text, data, and bss.
    590  */
    591 int
    592 make_ecoff_section_hdrs(ep, esecs)
    593 	struct ecoff_exechdr *ep;
    594 	struct ecoff_scnhdr *esecs;
    595 
    596 {
    597 	ep->f.f_nscns = 6;	/* XXX */
    598 
    599 	strcpy(esecs[0].s_name, ".text");
    600 	strcpy(esecs[1].s_name, ".data");
    601 	strcpy(esecs[2].s_name, ".bss");
    602 
    603 	esecs[0].s_paddr = esecs[0].s_vaddr = ep->a.text_start;
    604 	esecs[1].s_paddr = esecs[1].s_vaddr = ep->a.data_start;
    605 	esecs[2].s_paddr = esecs[2].s_vaddr = ep->a.bss_start;
    606 	esecs[0].s_size = ep->a.tsize;
    607 	esecs[1].s_size = ep->a.dsize;
    608 	esecs[2].s_size = ep->a.bsize;
    609 
    610 	esecs[0].s_scnptr = ECOFF_TXTOFF(ep);
    611 	esecs[1].s_scnptr = ECOFF_DATOFF(ep);
    612 #if 0
    613 	esecs[2].s_scnptr = esecs[1].s_scnptr +
    614 	    ECOFF_ROUND(esecs[1].s_size, ECOFF_SEGMENT_ALIGNMENT(ep));
    615 #endif
    616 
    617 	esecs[0].s_relptr = esecs[1].s_relptr = esecs[2].s_relptr = 0;
    618 	esecs[0].s_lnnoptr = esecs[1].s_lnnoptr = esecs[2].s_lnnoptr = 0;
    619 	esecs[0].s_nreloc = esecs[1].s_nreloc = esecs[2].s_nreloc = 0;
    620 	esecs[0].s_nlnno = esecs[1].s_nlnno = esecs[2].s_nlnno = 0;
    621 
    622 	esecs[1].s_flags = 0x100;	/* ECOFF rdata */
    623 	esecs[3].s_flags = 0x200;	/* ECOFF sdata */
    624 	esecs[4].s_flags = 0x400;	/* ECOFF sbss */
    625 
    626 	/*
    627 	 * Set the symbol-table offset  to point at the end of any
    628 	 * sections we loaded above, so later code can use it to write
    629 	 * symbol table info..
    630 	 */
    631 	ep->f.f_symptr = esecs[1].s_scnptr + esecs[1].s_size;
    632 	return (ep->f.f_nscns);
    633 }
    634 
    635 
    636 /*
    637  * Write the ECOFF symbol header.
    638  * Guess at how big the symbol table will be.
    639  * Mark all symbols as EXTERN (for now).
    640  */
    641 void
    642 write_ecoff_symhdr(out, ep, symhdrp, nesyms, extsymoff, extstroff, strsize)
    643 	int     out;
    644 	struct ecoff_exechdr *ep;
    645 	struct ecoff_symhdr *symhdrp;
    646 	long    nesyms, extsymoff, extstroff, strsize;
    647 {
    648 	if (debug)
    649 		fprintf(stderr, "writing symhdr for %ld entries at offset 0x%lx\n",
    650 		    nesyms, (u_long) ep->f.f_symptr);
    651 
    652 	ep->f.f_nsyms = sizeof(struct ecoff_symhdr);
    653 
    654 	memset(symhdrp, 0, sizeof(*symhdrp));
    655 	symhdrp->esymMax = nesyms;
    656 	symhdrp->magic = 0x7009;/* XXX */
    657 	symhdrp->cbExtOffset = extsymoff;
    658 	symhdrp->cbSsExtOffset = extstroff;
    659 
    660 	symhdrp->issExtMax = strsize;
    661 	if (debug)
    662 		fprintf(stderr,
    663 		    "ECOFF symhdr: symhdr %x, strsize %lx, symsize %lx\n",
    664 		    sizeof(*symhdrp), strsize,
    665 		    (nesyms * sizeof(struct ecoff_extsym)));
    666 
    667 	if (needswap) {
    668 		bswap32_region((u_int32_t*)&symhdrp->ilineMax,
    669 		    sizeof(*symhdrp) -  sizeof(symhdrp->magic) -
    670 		    sizeof(symhdrp->ilineMax));
    671 		symhdrp->magic = bswap16(symhdrp->magic);
    672 		symhdrp->ilineMax = bswap16(symhdrp->ilineMax);
    673 	}
    674 
    675 	safewrite(out, symhdrp, sizeof(*symhdrp),
    676 	    "writing symbol header: %s\n");
    677 }
    678 
    679 
    680 void
    681 elf_read_syms(elfsymsp, in, symoff, symsize, stroff, strsize)
    682 	struct elf_syms *elfsymsp;
    683 	int     in;
    684 	off_t   symoff, symsize;
    685 	off_t   stroff, strsize;
    686 {
    687 	register int nsyms;
    688 	int i;
    689 	nsyms = symsize / sizeof(Elf32_Sym);
    690 
    691 	/* Suck in the ELF symbol list... */
    692 	elfsymsp->elf_syms = (Elf32_Sym *)
    693 	    saveRead(in, symoff, nsyms * sizeof(Elf32_Sym),
    694 	    "ELF symboltable");
    695 	elfsymsp->nsymbols = nsyms;
    696 	if (needswap) {
    697 		for (i = 0; i < nsyms; i++) {
    698 			Elf32_Sym *s = &elfsymsp->elf_syms[i];
    699 			s->st_name	= bswap32(s->st_name);
    700 			s->st_value	= bswap32(s->st_value);
    701 			s->st_size	= bswap32(s->st_size);
    702 			s->st_shndx	= bswap16(s->st_shndx);
    703 		}
    704 	}
    705 
    706 	/* Suck in the ELF string table... */
    707 	elfsymsp->stringtab = (char *)
    708 	    saveRead(in, stroff, strsize, "ELF string table");
    709 	elfsymsp->stringsize = strsize;
    710 }
    711 
    712 
    713 /*
    714  *
    715  */
    716 void
    717 elf_symbol_table_to_ecoff(out, in, ep, symoff, symsize, stroff, strsize)
    718 	int     out, in;
    719 	struct ecoff_exechdr *ep;
    720 	off_t   symoff, symsize;
    721 	off_t   stroff, strsize;
    722 {
    723 
    724 	struct elf_syms elfsymtab;
    725 	struct ecoff_syms ecoffsymtab;
    726 	register u_long ecoff_symhdr_off, symtaboff, stringtaboff;
    727 	register u_long nextoff, symtabsize, ecoff_strsize;
    728 	int     nsyms, i;
    729 	struct ecoff_symhdr symhdr;
    730 	int     padding;
    731 
    732 	/* Read in the ELF symbols. */
    733 	elf_read_syms(&elfsymtab, in, symoff, symsize, stroff, strsize);
    734 
    735 	/* Approximate translation to ECOFF. */
    736 	translate_syms(&elfsymtab, &ecoffsymtab);
    737 	nsyms = ecoffsymtab.nsymbols;
    738 
    739 	/* Compute output ECOFF symbol- and string-table offsets. */
    740 	ecoff_symhdr_off = ep->f.f_symptr;
    741 
    742 	nextoff = ecoff_symhdr_off + sizeof(struct ecoff_symhdr);
    743 	stringtaboff = nextoff;
    744 	ecoff_strsize = ECOFF_ROUND(ecoffsymtab.stringsize,
    745 	    (ECOFF_SEGMENT_ALIGNMENT(ep)));
    746 
    747 
    748 	nextoff = stringtaboff + ecoff_strsize;
    749 	symtaboff = nextoff;
    750 	symtabsize = nsyms * sizeof(struct ecoff_extsym);
    751 	symtabsize = ECOFF_ROUND(symtabsize, ECOFF_SEGMENT_ALIGNMENT(ep));
    752 
    753 	/* Write out the symbol header ... */
    754 	write_ecoff_symhdr(out, ep, &symhdr, nsyms, symtaboff,
    755 	    stringtaboff, ecoffsymtab.stringsize);
    756 
    757 	/* Write out the string table... */
    758 	padding = ecoff_strsize - ecoffsymtab.stringsize;
    759 	safewrite(out, ecoffsymtab.stringtab, ecoffsymtab.stringsize,
    760 	    "string table: write: %s\n");
    761 	if (padding)
    762 		pad16(out, padding, "string table: padding: %s\n");
    763 
    764 
    765 	/* Write out the symbol table... */
    766 	padding = symtabsize - (nsyms * sizeof(struct ecoff_extsym));
    767 
    768 	for (i = 0; i < nsyms; i++) {
    769 		struct ecoff_extsym *es = &ecoffsymtab.ecoff_syms[i];
    770 		es->es_flags	= bswap16(es->es_flags);
    771 		es->es_ifd	= bswap16(es->es_ifd);
    772 		bswap32_region(&es->es_strindex,
    773 		    sizeof(*es) - sizeof(es->es_flags) - sizeof(es->es_ifd));
    774 	}
    775 	safewrite(out, ecoffsymtab.ecoff_syms,
    776 	    nsyms * sizeof(struct ecoff_extsym),
    777 	    "symbol table: write: %s\n");
    778 	if (padding)
    779 		pad16(out, padding, "symbols: padding: %s\n");
    780 }
    781 
    782 
    783 
    784 /*
    785  * In-memory translation of ELF symbosl to ECOFF.
    786  */
    787 void
    788 translate_syms(elfp, ecoffp)
    789 	struct elf_syms *elfp;
    790 	struct ecoff_syms *ecoffp;
    791 {
    792 
    793 	int     i;
    794 	char   *oldstringbase;
    795 	char   *newstrings, *nsp;
    796 
    797 	int     nsyms, idx;
    798 
    799 	nsyms = elfp->nsymbols;
    800 	oldstringbase = elfp->stringtab;
    801 
    802 	/* Allocate space for corresponding ECOFF symbols. */
    803 	memset(ecoffp, 0, sizeof(*ecoffp));
    804 
    805 	ecoffp->nsymbols = 0;
    806 	ecoffp->ecoff_syms = malloc(sizeof(struct ecoff_extsym) * nsyms);
    807 
    808 	/* we are going to be no bigger than the ELF symbol table. */
    809 	ecoffp->stringsize = elfp->stringsize;
    810 	ecoffp->stringtab = malloc(elfp->stringsize);
    811 
    812 	newstrings = (char *) ecoffp->stringtab;
    813 	nsp = (char *) ecoffp->stringtab;
    814 	if (!newstrings) {
    815 		fprintf(stderr, "No memory for new string table!\n");
    816 		exit(1);
    817 	}
    818 	/* Copy and translate  symbols... */
    819 	idx = 0;
    820 	for (i = 0; i < nsyms; i++) {
    821 		int     binding, type;
    822 
    823 		binding = ELF32_ST_BIND((elfp->elf_syms[i].st_info));
    824 		type = ELF32_ST_TYPE((elfp->elf_syms[i].st_info));
    825 
    826 		/* skip strange symbols */
    827 		if (binding == 0) {
    828 			continue;
    829 		}
    830 		/* Copy the symbol into the new table */
    831 		strcpy(nsp, oldstringbase + elfp->elf_syms[i].st_name);
    832 		ecoffp->ecoff_syms[idx].es_strindex = nsp - newstrings;
    833 		nsp += strlen(nsp) + 1;
    834 
    835 		/* translate symbol types to ECOFF XXX */
    836 		ecoffp->ecoff_syms[idx].es_type = 1;
    837 		ecoffp->ecoff_syms[idx].es_class = 5;
    838 
    839 		/* Symbol values in executables should be compatible. */
    840 		ecoffp->ecoff_syms[idx].es_value = elfp->elf_syms[i].st_value;
    841 		ecoffp->ecoff_syms[idx].es_symauxindex = 0xfffff;
    842 
    843 		idx++;
    844 	}
    845 
    846 	ecoffp->nsymbols = idx;
    847 	ecoffp->stringsize = nsp - newstrings;
    848 }
    849 /*
    850  * pad to a 16-byte boundary
    851  */
    852 void
    853 pad16(int fd, int size, const char *msg)
    854 {
    855 	safewrite(fd, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0", size, msg);
    856 }
    857 
    858 /* swap a 32bit region */
    859 void
    860 bswap32_region(u_int32_t* p, int len)
    861 {
    862 	int i;
    863 
    864 	for (i = 0; i < len / sizeof(u_int32_t); i++, p++)
    865 		*p = bswap32(*p);
    866 }
    867