/* Tang Yuhang <tyh000011112222@gmail.com> 2016 */
#include <string.h>
#include <ctype.h>
#include <errno.h>

#include <capstone.h>


void print_insn_detail_x86(csh ud, cs_mode mode, cs_insn *ins);
void print_insn_detail_arm(csh handle, cs_insn *ins);
void print_insn_detail_arm64(csh handle, cs_insn *ins);
void print_insn_detail_mips(csh handle, cs_insn *ins);
void print_insn_detail_ppc(csh handle, cs_insn *ins);
void print_insn_detail_sparc(csh handle, cs_insn *ins);
void print_insn_detail_sysz(csh handle, cs_insn *ins);
void print_insn_detail_xcore(csh handle, cs_insn *ins);

void print_string_hex(char *comment, unsigned char *str, size_t len)
{
	unsigned char *c;

	printf("%s", comment);
	for (c = str; c < str + len; c++) {
		printf("0x%02x ", *c & 0xff);
	}

	printf("\n");
}

// convert hexchar to hexnum
static uint8_t char_to_hexnum(char c)
{
	if (c >= '0' && c <= '9') {
		return (uint8_t)(c - '0');
	}

	if (c >= 'a' && c <= 'f') {
		return (uint8_t)(10 + c - 'a');
	}

	//  c >= 'A' && c <= 'F'
	return (uint8_t)(10 + c - 'A');
}

// convert user input (char[]) to uint8_t[], each element of which is
// valid hexadecimal, and return actual length of uint8_t[] in @size.
static uint8_t *preprocess(char *code, size_t *size)
{
	size_t i = 0, j = 0;
	uint8_t high, low;
	uint8_t *result;

	result = (uint8_t *)malloc(strlen(code));
	if (result != NULL) {
		while (code[i] != '\0') {
			if (isxdigit(code[i]) && isxdigit(code[i+1])) {
				high = 16 * char_to_hexnum(code[i]);
				low = char_to_hexnum(code[i+1]);
				result[j] = high + low;
				i++;
				j++;
			}
			i++;
		}
		*size = j;
	}

	return result;
}

static void usage(char *prog)
{
	printf("Cstool for Capstone Disassembler Engine v%u.%u.%u\n\n", CS_VERSION_MAJOR, CS_VERSION_MINOR, CS_VERSION_EXTRA);
	printf("Syntax: %s [-d] <arch+mode> <assembly-hexstring> [start-address-in-hex-format]\n", prog);
	printf("\nThe following <arch+mode> options are supported:\n");

	if (cs_support(CS_ARCH_X86)) {
		printf("        x16:       16-bit mode (X86)\n");
		printf("        x32:       32-bit mode (X86)\n");
		printf("        x64:       64-bit mode (X86)\n");
		printf("        x16att:    16-bit mode (X86) syntax-att\n");
		printf("        x32att:    32-bit mode (X86) syntax-att\n");
		printf("        x64att:    64-bit mode (X86) syntax-att\n");
	}

	if (cs_support(CS_ARCH_ARM)) {
		printf("        arm:       arm\n");
		printf("        armbe:     arm + big endian\n");
		printf("        thumb:     thumb mode\n");
		printf("        thumbbe:   thumb + big endian\n");
		printf("        cortexm:   thumb + cortex-m extensions\n");

	}

	if (cs_support(CS_ARCH_ARM64)) {
		printf("        arm64:     aarch64 mode\n");
		printf("        arm64be:   aarch64 + big endian\n");
	}

	if (cs_support(CS_ARCH_MIPS)) {
		printf("        mips:      mips32 + little endian\n");
		printf("        mipsbe:    mips32 + big endian\n");
		printf("        mips64:    mips64 + little endian\n");
		printf("        mips64be:  mips64 + big endian\n");
	}

	if (cs_support(CS_ARCH_PPC)) {
		printf("        ppc64:     ppc64 + little endian\n");
		printf("        ppc64be:   ppc64 + big endian\n");
	}

	if (cs_support(CS_ARCH_SPARC)) {
		printf("        sparc:     sparc\n");
	}

	if (cs_support(CS_ARCH_SYSZ)) {
		printf("        systemz:   systemz (s390x)\n");
	}

	if (cs_support(CS_ARCH_XCORE)) {
		printf("        xcore:     xcore\n");
	}

	printf("\n");
}

int main(int argc, char **argv)
{
	csh handle;
	char *mode;
	uint8_t *assembly;
	size_t count, size;
	uint64_t address = 0;
	cs_insn *insn;
	cs_err err;
	cs_mode md;
	cs_arch arch;
	bool detail_flag = false;
	bool x86_att_syntax = false;

	if (argc != 3 && argc != 4 && argc != 5) {
		usage(argv[0]);
		return -1;
	}

	if (!strcmp(argv[1], "-d")) {
		if (argc == 3) {
			usage(argv[0]);
			return -1;
		}
		detail_flag = true;
		mode = argv[2];
		assembly = preprocess(argv[3], &size);
		if (argc == 5) {
			char *temp;
			address = strtoull(argv[4], &temp, 16);
			if (temp == argv[4] || *temp != '\0' || errno == ERANGE) {
				printf("ERROR: invalid address argument, quit!\n");
				return -2;
			}
		}
	} else {
		if (argc == 5) {
			usage(argv[0]);
			return -1;
		}

		mode = argv[1];
		assembly = preprocess(argv[2], &size);
		if (assembly == NULL) {
			printf("ERROR: invalid assembler-string argument, quit!\n");
			return -3;
		}

		if (argc == 4) {
			// cstool <arch> <assembly> <address>
			char *temp;
			address = strtoull(argv[3], &temp, 16);
			if (temp == argv[3] || *temp != '\0' || errno == ERANGE) {
				printf("ERROR: invalid address argument, quit!\n");
				return -2;
			}
		}
	}

	if (!strcmp(mode, "arm") || !strcmp(mode, "arml") || !strcmp(mode, "armle")) {
		arch = CS_ARCH_ARM;
		md = CS_MODE_ARM | CS_MODE_LITTLE_ENDIAN;
	} else if (!strcmp(mode, "armb") || !strcmp(mode, "armbe") ) {
		arch = CS_ARCH_ARM;
		md = CS_MODE_ARM | CS_MODE_BIG_ENDIAN;
	} else if (!strcmp(mode, "thumb") || !strcmp(mode, "thumble")) {
		arch = CS_ARCH_ARM;
		md = CS_MODE_THUMB | CS_MODE_LITTLE_ENDIAN;
	} else if (!strcmp(mode, "thumbbe")) {
		arch = CS_ARCH_ARM;
		md = CS_MODE_THUMB | CS_MODE_BIG_ENDIAN;
	} else if (!strcmp(mode, "cortexm")) {
		arch = CS_ARCH_ARM;
		md = CS_MODE_THUMB | CS_MODE_MCLASS | CS_MODE_LITTLE_ENDIAN;
	} else if (!strcmp(mode, "arm64")) {
		arch = CS_ARCH_ARM64;
		md = CS_MODE_LITTLE_ENDIAN;
	} else if (!strcmp(mode, "arm64be")) {
		arch = CS_ARCH_ARM64;
		md = CS_MODE_BIG_ENDIAN;
	} else if (!strcmp(mode, "mips")) {
		arch = CS_ARCH_MIPS;
		md = CS_MODE_MIPS32 | CS_MODE_LITTLE_ENDIAN;
	} else if (!strcmp(mode, "mipsbe")) {
		arch = CS_ARCH_MIPS;
		md = CS_MODE_MIPS32 | CS_MODE_BIG_ENDIAN;
	} else if (!strcmp(mode, "mips64")) {
		arch = CS_ARCH_MIPS;
		md = CS_MODE_MIPS64 | CS_MODE_LITTLE_ENDIAN;
	} else if (!strcmp(mode, "mips64be")) {
		arch = CS_ARCH_MIPS;
		md = CS_MODE_MIPS64 | CS_MODE_BIG_ENDIAN;
	} else if (!strcmp(mode, "x16")) {
		arch = CS_ARCH_X86;
		md = CS_MODE_16;
	} else if (!strcmp(mode, "x32")) {
		arch = CS_ARCH_X86;
		md = CS_MODE_32;
	} else if (!strcmp(mode, "x64")) {
		arch = CS_ARCH_X86;
		md = CS_MODE_64;
	} else if (!strcmp(mode, "x16att")) {
		arch = CS_ARCH_X86;
		md = CS_MODE_16;
		x86_att_syntax = true;
	} else if (!strcmp(mode,"x32att")) {
		arch = CS_ARCH_X86;
		md = CS_MODE_32;
		x86_att_syntax = true;
	} else if (!strcmp(mode,"x64att")) {
		arch = CS_ARCH_X86;
		md = CS_MODE_64;
		x86_att_syntax = true;
	} else if (!strcmp(mode,"ppc64")) {
		arch = CS_ARCH_PPC;
		md = CS_MODE_64 | CS_MODE_LITTLE_ENDIAN;
	} else if (!strcmp(mode,"ppc64be")) {
		arch = CS_ARCH_PPC;
		md = CS_MODE_64 | CS_MODE_BIG_ENDIAN;
	} else if (!strcmp(mode,"sparc")) {
		arch = CS_ARCH_SPARC;
		md = CS_MODE_BIG_ENDIAN;
	} else if (!strcmp(mode, "systemz") || !strcmp(mode, "sysz") || !strcmp(mode, "s390x")) {
		arch = CS_ARCH_SYSZ;
		md = CS_MODE_BIG_ENDIAN;
	} else if (!strcmp(mode,"xcore")) {
		arch = CS_ARCH_XCORE;
		md = CS_MODE_BIG_ENDIAN;
	} else {
		printf("ERROR: unknown architecture '%s'!\n", mode);
		usage(argv[0]);
		return -1;
	}

	err = cs_open(arch, md, &handle);

	if (err) {
		printf("ERROR: Failed on cs_open(), quit!\n");
		usage(argv[0]);
		return -1;
	}

	if (arch == CS_ARCH_X86 && x86_att_syntax) {
		cs_option(handle, CS_OPT_SYNTAX, CS_OPT_SYNTAX_ATT);
	}

	if (detail_flag) {
		cs_option(handle, CS_OPT_DETAIL, CS_OPT_ON);
	}

	count = cs_disasm(handle, assembly, size, address, 0, &insn);
	if (count > 0) {
		size_t i;

		for (i = 0; i < count; i++) {
			int j;
			printf("%"PRIx64"  ", insn[i].address);
			for (j = 0; j < insn[i].size; j++) {
				if (j > 0)
					putchar(' ');
				printf("%02x", insn[i].bytes[j]);
			}
			// X86 instruction size is variable.
			// align assembly instruction after the opcode
			if (arch == CS_ARCH_X86) {

				for (; j < 16; j++) {
					printf("  ");
				}
			}

			printf("  %s\t%s\n", insn[i].mnemonic, insn[i].op_str);

			if (detail_flag) {
				if (arch == CS_ARCH_X86) {
					print_insn_detail_x86(handle, md, &insn[i]);
				}

				if (arch == CS_ARCH_ARM) {
					print_insn_detail_arm(handle, &insn[i]);
				}

				if (arch == CS_ARCH_ARM64) {
					print_insn_detail_arm64(handle,&insn[i]);
				}

				if (arch == CS_ARCH_MIPS) {
					print_insn_detail_mips(handle, &insn[i]);
				}

				if (arch == CS_ARCH_PPC) {
					print_insn_detail_ppc(handle, &insn[i]);
				}

				if (arch == CS_ARCH_SPARC) {
					print_insn_detail_sparc(handle, &insn[i]);
				}

				if (arch == CS_ARCH_SYSZ) {
					print_insn_detail_sysz(handle, &insn[i]);
				}

				if (arch == CS_ARCH_XCORE) {
					print_insn_detail_xcore(handle, &insn[i]);
				}

				if (insn[i].detail->groups_count) {
					int j;

					printf("\tGroups: ");
					for(j = 0; j < insn[i].detail->groups_count; j++) {
						printf("%s ", cs_group_name(handle, insn[i].detail->groups[j]));
					}
					printf("\n");
				}

				printf("\n");
			}
		}
		cs_free(insn, count);
	} else {
		printf("ERROR: invalid assembly code\n");
		return(-4);
	}

	cs_close(&handle);

	return 0;
}