/* * $Source$ * $State$ * * Simple tool to produce an utterly basic ELF executable * from an absolute ack.out file. Suitable for operating * systems like Linux. * * This tool produces an executable with a program header * only and no section header. * * Mostly pinched from the ARM cv (and then rewritten in * ANSI C). Which, according to the comment, was pinched * from m68k2; therefore I am merely continuing a time- * honoured tradition. * * (I was 10 when the original for this was checked into * CVS...) * * dtrg, 2006-10-17 */ #include #include #include #include #include #include #include "../../modules/src/object/obj.h" #include #include #include #include "out.h" #define ASSERT(x) switch (2) { case 0: case (x): ; } /* Global settings. */ int bigendian = 0; int elfmachine; /* Header and section table of an ack object file. */ struct outhead outhead; struct outsect outsect[S_MAX]; char* stringarea; char* outputfile = NULL; /* Name of output file, or NULL */ char* program; /* Name of current program: argv[0] */ FILE* input; /* Input stream */ FILE* output; /* Output stream */ #define readf(a, b, c) fread((a), (b), (int)(c), input) #define writef(a, b, c) fwrite((a), (b), (int)(c), output) /* Header and program header table of an ELF object file. */ #define ELF_HEADER_SIZE 0x34 #define PROGRAM_HEADER_SIZE 0x20 #define PROGRAM_HEADER_COUNT 1 unsigned long codeoffset; const char elf_le_ident_string[] = { 0x7F, 'E', 'L', 'F' }; /* Output file definitions and such */ #define HDR_LENGTH 32 char hdr[HDR_LENGTH] ; /* Segment numbers understood by aelflod. */ enum { TEXT = 0, ROM, DATA, BSS, NUM_SEGMENTS }; #define N_EXT 040 #define N_UNDEF 00 #define N_ABS 01 #define N_TEXT 02 #define N_DATA 03 #define N_BSS 04 #define N_FN 037 /* Produce an error message and exit. */ void fatal(const char* s, ...) { va_list ap; fprintf(stderr, "%s: ",program) ; va_start(ap, s); vfprintf(stderr, s, ap); va_end(ap); fprintf(stderr, "\n"); if (outputfile) unlink(outputfile); exit(1); } /* Calculate the result of a aligned to b (rounding up if necessary). * b must be a power of two. */ long align(long a, long b) { a += b - 1; return a & ~(b-1); } int follows(struct outsect* pa, struct outsect* pb) { /* return 1 if pa follows pb */ return (pa->os_base == align(pb->os_base+pb->os_size, pa->os_lign)); } /* Writes a byte. */ void emit8(unsigned char value) { writef(&value, 1, 1); } /* Writes out 16 and 32 bit words in the appropriate endianness. */ void emit16(unsigned short value) { unsigned char buffer[2]; if (bigendian) { buffer[0] = (value >> 8) & 0xFF; buffer[1] = (value >> 0) & 0xFF; } else { buffer[1] = (value >> 8) & 0xFF; buffer[0] = (value >> 0) & 0xFF; } writef(buffer, 1, sizeof(buffer)); } void emit32(unsigned long value) { unsigned char buffer[4]; if (bigendian) { buffer[0] = (value >> 24) & 0xFF; buffer[1] = (value >> 16) & 0xFF; buffer[2] = (value >> 8) & 0xFF; buffer[3] = (value >> 0) & 0xFF; } else { buffer[3] = (value >> 24) & 0xFF; buffer[2] = (value >> 16) & 0xFF; buffer[1] = (value >> 8) & 0xFF; buffer[0] = (value >> 0) & 0xFF; } writef(buffer, 1, sizeof(buffer)); } /* Copies the contents of a section from the input stream * to the output stream. */ void emits(struct outsect* section) { char buffer[BUFSIZ]; long n = section->os_flen; while (n > 0) { int blocksize = (n > BUFSIZ) ? BUFSIZ : n; readf(buffer, 1, blocksize); writef(buffer, 1, blocksize); n -= blocksize; } /* Zero fill any remaining space. */ if (section->os_flen != section->os_size) { long n = section->os_size - section->os_flen; memset(buffer, 0, BUFSIZ); while (n > 0) { int blocksize = (n > BUFSIZ) ? BUFSIZ : n; writef(buffer, 1, blocksize); n -= blocksize; } } } /* Writes out an ELF program header. */ void emitphdr(unsigned long address, unsigned long filesize, unsigned int memsize, unsigned int alignment, int flags) { static unsigned long fileoffset = 0; emit32(1); /* type = PT_LOAD */ emit32(fileoffset); /* file offset */ emit32(address); /* virtual address */ emit32(0); /* physical address */ emit32(filesize); /* file size */ emit32(memsize); /* memory size */ emit32(flags); /* executable, readable, writable */ emit32(alignment); /* alignment */ fileoffset += filesize; } /* Read the ack.out file header. */ int rhead(FILE* f, struct outhead* head) { char buf[SZ_HEAD], *c; if (fread(buf, sizeof(buf), 1, f) != 1) return 0; c = buf; head->oh_magic = uget2(c); c += 2; head->oh_stamp = uget2(c); c += 2; head->oh_flags = uget2(c); c += 2; head->oh_nsect = uget2(c); c += 2; head->oh_nrelo = uget2(c); c += 2; head->oh_nname = uget2(c); c += 2; head->oh_nemit = get4(c); c += 4; head->oh_nchar = get4(c); return 1; } /* Read an ack.out section header. */ int rsect(FILE* f, struct outsect* sect) { char buf[SZ_SECT], *c; if (fread(buf, sizeof(buf), 1, f) != 1) return 0; c = buf; sect->os_base = get4(c); c += 4; sect->os_size = get4(c); c += 4; sect->os_foff = get4(c); c += 4; sect->os_flen = get4(c); c += 4; sect->os_lign = get4(c); return 1 ; } int main(int argc, char* argv[]) { /* General housecleaning and setup. */ input = stdin; output = stdout; program = argv[0]; /* Read in and process any flags. */ while ((argc > 1) && (argv[1][0] == '-')) { switch (argv[1][1]) { case 'h': fprintf(stderr, "%s: Syntax: aelflod [-h] \n", program); exit(0); default: syntaxerror: fatal("syntax error --- try -h for help"); } argv++; argc--; } /* Process the rest of the arguments. */ switch (argc) { case 1: /* No parameters --- read from stdin, write to stdout. */ break; case 3: /* Both input and output files specified. */ output = fopen(argv[2], "w"); if (!output) fatal("unable to open output file."); outputfile = argv[2]; /* fall through */ case 2: /* Input file specified. */ input = fopen(argv[1], "r"); if (!input) fatal("unable to open input file."); break; default: goto syntaxerror; } /* Read and check the ack.out file header. */ if (!rhead(input,&outhead)) fatal("failed to read file header."); if (BADMAGIC(outhead)) fatal("this isn't an ack object file."); if (outhead.oh_nrelo > 0) fprintf(stderr, "Warning: relocation information present."); if (!((outhead.oh_nsect == NUM_SEGMENTS) || (outhead.oh_nsect == (NUM_SEGMENTS+1)))) fatal("the input file must have %d sections, not %ld.", NUM_SEGMENTS, outhead.oh_nsect); /* Read in the section headers. */ { int i; for (i=0; i