| /* SPDX-License-Identifier: BSD-2-Clause */ |
| /* Copyright 1996-2025 The NASM Authors - All Rights Reserved */ |
| |
| /* |
| * ndisasm.c the Netwide Disassembler main module |
| */ |
| |
| #include "compiler.h" |
| |
| #include "nctype.h" |
| #include <errno.h> |
| |
| #include "insns.h" |
| #include "nasm.h" |
| #include "nasmlib.h" |
| #include "error.h" |
| #include "ver.h" |
| #include "sync.h" |
| #include "disasm.h" |
| |
| const char *_progname; |
| |
| static int bpl = 8; /* bytes per line of hex dump */ |
| |
| static void output_ins(uint64_t, const uint8_t *, int, const char *); |
| static bool skip(off_t *posp, off_t dist, FILE *fp); |
| |
| int main(int argc, char **argv) |
| { |
| uint8_t buffer[INSN_MAX * 2], *p; |
| const uint8_t *q; |
| char outbuf[256]; |
| char *pname = *argv; |
| char *filename = NULL; |
| uint64_t nextsync, synclen; |
| size_t lenread; |
| bool autosync = false; |
| int bits = 16, b; |
| bool eof; |
| iflag_t prefer; |
| bool rn_error; |
| uint64_t offset, dataread, datamax; |
| off_t fileoffs, initskip; |
| FILE *fp; |
| |
| _progname = argv[0]; |
| |
| reset_global_defaults(0); |
| nasm_ctype_init(); |
| iflag_clear_all(&prefer); |
| |
| offset = 0; |
| datamax = UINT64_C(-1); |
| initskip = 0; |
| |
| init_sync(); |
| |
| while (--argc) { |
| char *v, *vv, *p = *++argv; |
| if (*p == '-' && p[1]) { |
| p++; |
| while (*p) |
| switch (nasm_tolower(*p)) { |
| case 'a': /* auto or intelligent sync */ |
| case 'i': |
| autosync = true; |
| p++; |
| break; |
| case 'h': |
| usage(); |
| return 0; |
| case 'r': |
| case 'v': |
| fprintf(stderr, |
| "NDISASM version %s compiled on %s\n", |
| nasm_version, nasm_date); |
| return 0; |
| case 'u': /* -u for -b 32, -uu for -b 64 */ |
| if (bits < 64) |
| bits <<= 1; |
| p++; |
| break; |
| case 'l': |
| bits = 64; |
| p++; |
| break; |
| case 'w': |
| bpl = 16; |
| p++; |
| break; |
| case 'z': /* max number of bytes to read */ |
| v = p[1] ? p + 1 : --argc ? *++argv : NULL; |
| if (!v) { |
| fprintf(stderr, "%s: `-z' requires an argument\n", |
| pname); |
| return 1; |
| } |
| datamax = readnum(v, &rn_error); |
| if (rn_error) { |
| fprintf(stderr, |
| "%s: `-z' requires a numeric argument\n", |
| pname); |
| return 1; |
| } |
| p = ""; /* force to next argument */ |
| break; |
| |
| case 'b': /* bits */ |
| v = p[1] ? p + 1 : --argc ? *++argv : NULL; |
| if (!v) { |
| fprintf(stderr, "%s: `-b' requires an argument\n", |
| pname); |
| return 1; |
| } |
| b = readnum(v, &rn_error); |
| if (rn_error || |
| !(bits == 16 || bits == 32 || bits == 64)) { |
| fprintf(stderr, "%s: argument to `-b' should" |
| " be 16, 32 or 64\n", pname); |
| } else { |
| bits = b; |
| } |
| p = ""; /* force to next argument */ |
| break; |
| case 'o': /* origin */ |
| v = p[1] ? p + 1 : --argc ? *++argv : NULL; |
| if (!v) { |
| fprintf(stderr, "%s: `-o' requires an argument\n", |
| pname); |
| return 1; |
| } |
| offset = readnum(v, &rn_error); |
| if (rn_error) { |
| fprintf(stderr, |
| "%s: `-o' requires a numeric argument\n", |
| pname); |
| return 1; |
| } |
| p = ""; /* force to next argument */ |
| break; |
| case 's': /* sync point */ |
| v = p[1] ? p + 1 : --argc ? *++argv : NULL; |
| if (!v) { |
| fprintf(stderr, "%s: `-s' requires an argument\n", |
| pname); |
| return 1; |
| } |
| add_sync(readnum(v, &rn_error), 0L); |
| if (rn_error) { |
| fprintf(stderr, |
| "%s: `-s' requires a numeric argument\n", |
| pname); |
| return 1; |
| } |
| p = ""; /* force to next argument */ |
| break; |
| case 'e': /* skip a header */ |
| v = p[1] ? p + 1 : --argc ? *++argv : NULL; |
| if (!v) { |
| fprintf(stderr, "%s: `-e' requires an argument\n", |
| pname); |
| return 1; |
| } |
| initskip = readnum(v, &rn_error); |
| if (rn_error) { |
| fprintf(stderr, |
| "%s: `-e' requires a numeric argument\n", |
| pname); |
| return 1; |
| } |
| p = ""; /* force to next argument */ |
| break; |
| case 'k': /* skip a region */ |
| v = p[1] ? p + 1 : --argc ? *++argv : NULL; |
| if (!v) { |
| fprintf(stderr, "%s: `-k' requires an argument\n", |
| pname); |
| return 1; |
| } |
| vv = strchr(v, ','); |
| if (!vv) { |
| fprintf(stderr, |
| "%s: `-k' requires two numbers separated" |
| " by a comma\n", pname); |
| return 1; |
| } |
| *vv++ = '\0'; |
| nextsync = readnum(v, &rn_error); |
| if (rn_error) { |
| fprintf(stderr, |
| "%s: `-k' requires numeric arguments\n", |
| pname); |
| return 1; |
| } |
| synclen = readnum(vv, &rn_error); |
| if (rn_error) { |
| fprintf(stderr, |
| "%s: `-k' requires numeric arguments\n", |
| pname); |
| return 1; |
| } |
| add_sync(nextsync, synclen); |
| p = ""; /* force to next argument */ |
| break; |
| case 'p': /* preferred vendor */ |
| v = p[1] ? p + 1 : --argc ? *++argv : NULL; |
| if (!v) { |
| fprintf(stderr, "%s: `-p' requires an argument\n", |
| pname); |
| return 1; |
| } |
| if (!strcmp(v, "intel")) { |
| iflag_clear_all(&prefer); /* default */ |
| } else if (!strcmp(v, "amd")) { |
| iflag_clear_all(&prefer); |
| iflag_set(&prefer, IF_AMD); |
| iflag_set(&prefer, IF_3DNOW); |
| } else if (!strcmp(v, "cyrix")) { |
| iflag_clear_all(&prefer); |
| iflag_set(&prefer, IF_CYRIX); |
| iflag_set(&prefer, IF_3DNOW); |
| } else if (!strcmp(v, "idt") || |
| !strcmp(v, "centaur") || |
| !strcmp(v, "winchip")) { |
| iflag_clear_all(&prefer); |
| iflag_set(&prefer, IF_3DNOW); |
| } else { |
| fprintf(stderr, |
| "%s: unknown vendor `%s' specified with `-p'\n", |
| pname, v); |
| return 1; |
| } |
| p = ""; /* force to next argument */ |
| break; |
| default: /*bf */ |
| fprintf(stderr, "%s: unrecognised option `-%c'\n", |
| pname, *p); |
| return 1; |
| } |
| } else if (!filename) { |
| filename = p; |
| } else { |
| fprintf(stderr, "%s: more than one filename specified\n", |
| pname); |
| return 1; |
| } |
| } |
| |
| if (!filename) { |
| usage(); |
| return 1; |
| } |
| |
| if (strcmp(filename, "-")) { |
| fp = fopen(filename, "rb"); |
| if (!fp) { |
| fprintf(stderr, "%s: unable to open `%s': %s\n", |
| pname, filename, strerror(errno)); |
| return 1; |
| } |
| } else { |
| nasm_set_binary_mode(stdin); |
| fp = stdin; |
| } |
| |
| reset_global_defaults(bits); |
| |
| fileoffs = 0; |
| dataread = 0; |
| if (!skip(&fileoffs, initskip, fp)) |
| return 1; /* EOF before header */ |
| |
| /* |
| * This main loop is really horrible, and wants rewriting with |
| * an axe. It'll stay the way it is for a while though, until I |
| * find the energy... |
| */ |
| |
| q = p = buffer; |
| nextsync = next_sync(offset, &synclen); |
| lenread = 0; |
| eof = false; |
| |
| while (lenread > 0 || (dataread < datamax && !eof && !feof(fp))) { |
| size_t to_read = buffer + sizeof(buffer) - p; |
| if ((nextsync || synclen) && |
| to_read > nextsync - offset - (p - q)) |
| to_read = nextsync - offset - (p - q); |
| if (to_read > datamax - dataread) |
| to_read = datamax - dataread; |
| |
| lenread = 0; |
| if (to_read) { |
| lenread = fread(p, 1, to_read, fp); |
| dataread += lenread; |
| fileoffs += lenread; |
| p += lenread; |
| eof |= !lenread; /* help along systems with bad feof */ |
| } |
| |
| if ((nextsync || synclen) && offset == nextsync) { |
| if (synclen) { |
| fprintf(stdout, "%08"PRIX64" skipping 0x%"PRIX64" bytes\n", |
| offset, synclen); |
| offset += synclen; |
| dataread += synclen; |
| eof |= skip(&fileoffs, synclen, fp); |
| } |
| q = p = buffer; |
| nextsync = next_sync(offset, &synclen); |
| } |
| while (p > q && (p - q >= INSN_MAX || lenread == 0)) { |
| size_t lendis = disasm(q, INSN_MAX, outbuf, sizeof(outbuf), |
| bits, offset, autosync, &prefer); |
| if (!lendis || q + lendis > p || |
| ((nextsync || synclen) && lendis > nextsync - offset)) |
| lendis = eatbyte(*q, outbuf, sizeof(outbuf), bits); |
| output_ins(offset, q, lendis, outbuf); |
| q += lendis; |
| offset += lendis; |
| } |
| if (q >= buffer + INSN_MAX) { |
| int count = p - q; |
| memmove(buffer, q, count); |
| p -= (q - buffer); |
| q = buffer; |
| } |
| } |
| |
| if (fp != stdin) |
| fclose(fp); |
| |
| return 0; |
| } |
| |
| static void output_ins(uint64_t offset, const uint8_t *data, |
| int datalen, const char *insn) |
| { |
| int bytes; |
| int addrwidth; |
| addrwidth = fprintf(stdout, "%08"PRIX64" ", offset); |
| |
| bytes = 0; |
| while (datalen > 0 && bytes < bpl) { |
| fprintf(stdout, "%02X", *data++); |
| bytes++; |
| datalen--; |
| } |
| |
| fprintf(stdout, "%*s %s\n", (bpl - bytes) << 1, "", insn); |
| |
| while (datalen > 0) { |
| fprintf(stdout, "%*s", addrwidth, "-"); |
| bytes = 0; |
| while (datalen > 0 && bytes < bpl) { |
| fprintf(stdout, "%02X", *data++); |
| bytes++; |
| datalen--; |
| } |
| putchar('\n'); |
| } |
| } |
| |
| /* |
| * Skip a certain amount of data in a file, either by seeking if |
| * possible, or if that fails then by reading and discarding. |
| * Returns true if successful, false on EOF; updates posp. |
| */ |
| static bool skip(off_t *posp, off_t dist, FILE *fp) |
| { |
| if (!dist) |
| return true; |
| |
| /* |
| * Got to be careful with fseek: at least one fseek I've tried |
| * doesn't approve of SEEK_CUR (WHICH ONE?). Weird... |
| */ |
| if (!fseeko(fp, *posp + dist, SEEK_SET)) { |
| *posp += dist; |
| } else { |
| off_t pos = ftello(fp); |
| if (pos != (off_t)-1) { |
| /* Possibly a partial seek? */ |
| dist -= (pos - *posp); |
| *posp = pos; |
| } |
| |
| while (dist > 0) { |
| static char junk_buf[BUFSIZ]; |
| size_t len = sizeof junk_buf; |
| size_t skipped; |
| if (dist < (off_t)len) |
| len = dist; |
| skipped = fread(junk_buf, 1, len, fp); |
| dist -= skipped; |
| *posp += skipped; |
| if (skipped < len) |
| return false; /* EOF */ |
| } |
| } |
| |
| return true; |
| } |
