utils.c

/* Capstone Disassembly Engine */
/* By Nguyen Anh Quynh <aquynh@gmail.com>, 2013-2019 */

#if defined(CAPSTONE_HAS_OSXKERNEL)
#include <Availability.h>
#include <libkern/libkern.h>
#else
#include <stdlib.h>
#endif
#include <string.h>

#include "utils.h"

// count number of positive members in a list.
// NOTE: list must be guaranteed to end in 0
unsigned int count_positive(const uint16_t *list)
{
	unsigned int c;

	for (c = 0; list[c] > 0; c++);

	return c;
}

// count number of positive members in a list.
// NOTE: list must be guaranteed to end in 0
unsigned int count_positive8(const unsigned char *list)
{
	unsigned int c;

	for (c = 0; list[c] > 0; c++);

	return c;
}

char *cs_strdup(const char *str)
{
	size_t len = strlen(str) + 1;
	void *new = cs_mem_malloc(len);

	if (new == NULL)
		return NULL;

	return (char *)memmove(new, str, len);
}

// we need this since Windows doesn't have snprintf()
int cs_snprintf(char *buffer, size_t size, const char *fmt, ...)
{
	int ret;

	va_list ap;
	va_start(ap, fmt);
	ret = cs_vsnprintf(buffer, size, fmt, ap);
	va_end(ap);

	return ret;
}

bool arr_exist8(unsigned char *arr, unsigned char max, unsigned int id)
{
	int i;

	for (i = 0; i < max; i++) {
		if (arr[i] == id)
			return true;
	}

	return false;
}

bool arr_exist(uint16_t *arr, unsigned char max, unsigned int id)
{
	int i;

	for (i = 0; i < max; i++) {
		if (arr[i] == id)
			return true;
	}

	return false;
}

// binary search for encoding in IndexType array
// return -1 if not found, or index if found
unsigned int binsearch_IndexTypeEncoding(const struct IndexType *index, size_t size, uint16_t encoding)
{
	// binary searching since the index is sorted in encoding order
	size_t left, right, m;

	right = size - 1;

	if (encoding < index[0].encoding || encoding > index[right].encoding)
		// not found
		return -1;

	left = 0;

	while(left <= right) {
		m = (left + right) / 2;
		if (encoding == index[m].encoding) {
			return m;
		}

		if (encoding < index[m].encoding)
			right = m - 1;
		else
			left = m + 1;
	}

	// not found
	return -1;
}

/// Reads 4 bytes in the endian order specified in MI->cs->mode.
uint32_t readBytes32(MCInst *MI, const uint8_t *Bytes)
{
	assert(MI && Bytes);
	uint32_t Insn;
	if (MODE_IS_BIG_ENDIAN(MI->csh->mode))
		Insn = (Bytes[3] << 0) | (Bytes[2] << 8) | (Bytes[1] << 16) |
		       ((uint32_t)Bytes[0] << 24);
	else
		Insn = ((uint32_t)Bytes[3] << 24) | (Bytes[2] << 16) |
		       (Bytes[1] << 8) | (Bytes[0] << 0);
	return Insn;
}

/// Reads 2 bytes in the endian order specified in MI->cs->mode.
uint16_t readBytes16(MCInst *MI, const uint8_t *Bytes)
{
	assert(MI && Bytes);
	uint16_t Insn;
	if (MODE_IS_BIG_ENDIAN(MI->csh->mode))
		Insn = (Bytes[0] << 8) | Bytes[1];
	else
		Insn = (Bytes[1] << 8) | Bytes[0];

	return Insn;
}