# HG changeset patch # User lost # Date 1232764465 0 # Node ID 8272b46b5a34bb5c5d50366160852fb6631d8616 # Parent 3476629ee0ced0a3a977fc5be2f200fcd13dfaba Added lwobjdump for debugging object files diff -r 3476629ee0ce -r 8272b46b5a34 src/Makefile.am --- a/src/Makefile.am Sat Jan 24 02:22:13 2009 +0000 +++ b/src/Makefile.am Sat Jan 24 02:34:25 2009 +0000 @@ -1,3 +1,4 @@ -bin_PROGRAMS = lwlink +bin_PROGRAMS = lwlink lwobjdump lwlink_SOURCES = main.c lwlink.c util.c readfiles.c expr.c script.c link.c output.c +lwobjdump_SOURCES = objdump.c util.c EXTRA_DIST = lwlink.h util.h expr.h diff -r 3476629ee0ce -r 8272b46b5a34 src/objdump.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/objdump.c Sat Jan 24 02:34:25 2009 +0000 @@ -0,0 +1,303 @@ +/* +objdump.c +Copyright © 2009 William Astle + +This file is part of LWLINK + +LWLINK 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, see . + + +A standalone program to dump an object file in a text form to stdout + +*/ + +#include +#include + +#include "util.h" + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +void read_lwobj16v0(unsigned char *filedata, long filesize); + +/* +The logic of reading the entire file into memory is simple. All the symbol +names in the file are NUL terminated strings and can be used directly without +making additional copies. +*/ +int main(int argc, char **argv) +{ + int i; + long size; + FILE *f; + long bread; + unsigned char *filedata; + + if (argc != 2) + { + fprintf(stderr, "Must specify exactly one input file.\n"); + exit(1); + } + + f = fopen(argv[1], "rb"); + if (!f) + { + fprintf(stderr, "Can't open file %s:", argv[1]); + perror(""); + exit(1); + } + fseek(f, 0, SEEK_END); + size = ftell(f); + rewind(f); + + filedata = lw_malloc(size); + + bread = fread(filedata, 1, size, f); + if (bread < size) + { + fprintf(stderr, "Short read on file %s (%ld/%ld):", argv[1], bread, size); + perror(""); + exit(1); + } + + fclose(f); + + if (!memcmp(filedata, "LWOBJ16", 8)) + { + // read v0 LWOBJ16 file + read_lwobj16v0(filedata, size); + } + else + { + fprintf(stderr, "%s: unknown file format\n", argv[1]); + exit(1); + } + exit(0); +} + +// this macro is used to bail out if we run off the end of the file data +// while parsing - it keeps the code below cleaner +#define NEXTBYTE() do { cc++; if (cc > filesize) { fprintf(stderr, "***invalid file format\n"); exit(1); } } while (0) +// this macro is used to refer to the current byte in the stream +#define CURBYTE() (filedata[cc < filesize ? cc : filesize - 1]) +// this one will leave the input pointer past the trailing NUL +#define CURSTR() read_lwobj16v0_str(&cc, &filedata, filesize) +unsigned char *read_lwobj16v0_str(long *cc1, unsigned char **filedata1, long filesize) +{ + int cc = *cc1; + unsigned char *filedata = *filedata1; + unsigned char *fp; + fp = &CURBYTE(); + while (CURBYTE()) + NEXTBYTE(); + NEXTBYTE(); + *cc1 = cc; + *filedata1 = filedata; + return fp; +} +// the function below can be switched to dealing with data coming from a +// source other than an in-memory byte pool by adjusting the input data +// in "fn" and the above two macros +void read_lwobj16v0(unsigned char *filedata, long filesize) +{ + unsigned char *fp; + long cc; + int val; + int bss; + + static char *opernames[] = { + "?", + "PLUS", + "MINUS", + "TIMES", + "DIVIDE", + "MOD", + "INTDIV", + "BWAND", + "BWOR", + "BWXOR", + "AND", + "OR", + "NEG", + "COM" + }; + static const int numopers = 13; + + // start reading *after* the magic number + cc = 8; + + while (1) + { + bss = 0; + + // bail out if no more sections + if (!(CURBYTE())) + break; + + fp = CURSTR(); + + printf("SECTION %s\n", fp); + + // read flags + while (CURBYTE()) + { + switch (CURBYTE()) + { + case 0x01: + printf(" FLAG: BSS\n"); + bss = 1; + break; + + default: + printf(" FLAG: %02X (unknown)\n", CURBYTE()); + break; + } + NEXTBYTE(); + } + // skip NUL terminating flags + NEXTBYTE(); + + printf(" Local symbols:\n"); + // now parse the local symbol table + while (CURBYTE()) + { + fp = CURSTR(); + + // fp is the symbol name + val = (CURBYTE()) << 8; + NEXTBYTE(); + val |= (CURBYTE()); + NEXTBYTE(); + // val is now the symbol value + + printf(" %s=%04X\n", fp, val); + + } + // skip terminating NUL + NEXTBYTE(); + + printf(" Exported symbols\n"); + + // now parse the exported symbol table + while (CURBYTE()) + { + fp = CURSTR(); + + // fp is the symbol name + val = (CURBYTE()) << 8; + NEXTBYTE(); + val |= (CURBYTE()); + NEXTBYTE(); + // val is now the symbol value + + printf(" %s=%04X\n", fp, val); + } + // skip terminating NUL + NEXTBYTE(); + + // now parse the incomplete references and make a list of + // external references that need resolution + printf(" Incomplete references\n"); + while (CURBYTE()) + { + printf(" ("); + // parse the expression + while (CURBYTE()) + { + int tt = CURBYTE(); + NEXTBYTE(); + switch (tt) + { + case 0x01: + // 16 bit integer + tt = CURBYTE() << 8; + NEXTBYTE(); + tt |= CURBYTE(); + NEXTBYTE(); + // normalize for negatives... + if (tt > 0x7fff) + tt -= 0x10000; + printf(" I16=%d", tt); + break; + + case 0x02: + // external symbol reference + printf(" ES=%s", CURSTR()); + break; + + case 0x03: + // internal symbol reference + printf(" IS=%s", CURSTR()); + break; + + case 0x04: + // operator + if (CURBYTE() > 0 && CURBYTE() <= numopers) + printf(" OP=%s", opernames[CURBYTE()]); + else + printf(" OP=?"); + NEXTBYTE(); + break; + + case 0x05: + // section base reference (NULL internal reference is + // the section base address + printf(" SB"); + break; + + default: + printf(" ERR"); + } + } + // skip the NUL + NEXTBYTE(); + + // fetch the offset + val = CURBYTE() << 8; + NEXTBYTE(); + val |= CURBYTE() & 0xff; + NEXTBYTE(); + printf(" ) @ %04X\n", val); + } + // skip the NUL terminating the relocations + NEXTBYTE(); + + // now set code location and size and verify that the file + // contains data going to the end of the code (if !SECTION_BSS) + val = CURBYTE() << 8; + NEXTBYTE(); + val |= CURBYTE(); + NEXTBYTE(); + + printf(" CODE %04X bytes", val); + + // skip the code if we're not in a BSS section + if (!bss) + { + int i; + for (i = 0; i < val; i++) + { + if (! (i % 16)) + { + printf("\n %04X ", i); + } + printf("%02X", CURBYTE()); + NEXTBYTE(); + } + } + printf("\n"); + } +}