recomp.c

/* Bvim - BVi IMproved, binary analysis framework
 *
 * Copyright 1996-2004 by Gerhard Buergmann <gerhard@puon.at>
 * Copyright 2011 by Anton Kochkov <anton.kochkov@gmail.com>
 *
 * This file is part of Bvim.
 *
 * Bvim 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.
 *
 * Bvim 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 Bvim.  If not, see <http://www.gnu.org/licenses/>.
 */ 

/* You cannot use a common regexp subroutine, because \0 is a regular
 * character in a binary string !
 */

#include	"bvim.h"
#include	"blocks.h"
#include	"set.h"
#include	"ui.h"

#include	"messages.h"

char *poi;
int smode;
int again = 0;
int magic = 1;
int ignore_case = 0;

extern long bytepos;
extern int ignore_case;

/*
 *  Compiling an ASCII sequence to a regex string
 */
// TODO: Add return codes/error codes
int ascii_comp(smem, pattern)
char *smem;
char *pattern;
{
	char *end;
	char *comp;
	char cc, cc1;
	char *counter;
	int count;
	int bracket, dot;

	comp = smem;
	poi = pattern;
	while (*poi != END) {
		bracket = FALSE;
		if (magic) {
			if (*poi == '[')
				bracket = TRUE;
		} else {
			if (*poi == '\\' && *(poi + 1) == '[') {
				bracket = TRUE;
				poi++;
			}
		}
		if (bracket) {
			if (!(end = strchr(poi, ']'))) {
				//bvim_error(core, buf, "Missing ]");
				return 1;
			}
			poi++;
			if (*poi == ']' || (*poi == '^' && *(poi + 1) == ']')) {
				//bvim_error(core, buf, BVI_ERROR_EMPTYCLASS);
				return 1;
			}
			if (magic) {
				if (*(end + 1) == '*')
					*comp++ = STAR;
				else
					*comp++ = ONE;
			} else {
				if (*(end + 1) == '\\' && *(end + 2) == '*')
					*comp++ = STAR;
				else
					*comp++ = ONE;
			}
			count = 0;
			counter = comp;
			comp++;
			if (*poi != '^') {
				*comp++ = '\0';
				count++;
			}

			while (end > poi) {
				if (*poi == '-') {
					if (ignore_case) {
						cc = toupper(*(poi - 1));
						cc1 = toupper(*(poi + 1));
					} else {
						cc = *(poi - 1);
						cc1 = *(poi + 1);
					}
					while (cc <= cc1) {
						*comp++ = cc++;
						count++;
					}
					poi++;
					poi++;
				} else {
					count++;
					if (ignore_case)
						*comp++ = toupper(*poi++);
					else
						*comp++ = *poi++;
				}
			}
			poi++;
			*counter = count;
		} else {
			dot = FALSE;
			if (magic) {
				if (*poi == '.')
					dot = TRUE;
			} else {
				if (*poi == '\\' && *(poi + 1) == '.') {
					dot = TRUE;
					poi++;
				}
			}

			if (*poi == '\\') {
				switch (*(poi + 1)) {
				case 'n':
					*++poi = '\n';
					break;
				case 'r':
					*++poi = '\r';
					break;
				case 't':
					*++poi = '\t';
					break;
				case '0':
					*++poi = '\0';
					break;
				default:
					++poi;
				}
			}
			if (magic)
				if (*(poi + 1) == '*')
					*comp++ = STAR;
				else
					*comp++ = ONE;
			else if (*(poi + 1) == '\\' && *(poi + 2) == '*')
				*comp++ = STAR;
			else
				*comp++ = ONE;

			if (dot) {
				*comp++ = 0;
				poi++;
			} else {
				*comp++ = 1;
				if (ignore_case)
					*comp++ = toupper(*poi++);
				else
					*comp++ = *poi++;
			}
		}
		if (magic) {
			if (*poi == '*')
				poi++;
		} else {
			if (*poi == '\\' && *(poi + 1) == '*') {
				poi++;
				poi++;
			}
		}
	}
	*comp = END;
	smode = ASCII;
	return 0;
}

/*
 * Compiling a hex expression to a regex string
 */
// TODO: Add return codes/error codes
int hex_comp(smem, pattern)
char *smem;
char *pattern;
{
	char *end;
	char *comp;
	int cc, ccm;
	char *counter;
	int count, nr;

	comp = smem;
	poi = pattern;
	while (*poi != END) {
		while (*poi == ' ' || *poi == '\t')
			poi++;
		if (*poi == '[') {
			if (!(end = strchr(poi, ']'))) {
				//bvim_error(core, buf, "Missing ]");
				return 1;
			}
			poi++;
			while (*poi == ' ' || *poi == '\t')
				poi++;

			if (*poi == ']' || (*poi == '^' && *(poi + 1) == ']')) {
				//bvim_error(core, buf, BVI_ERROR_EMPTYCLASS);
				return 1;
			}
			if (*(end + 1) == '*')
				*comp++ = STAR;
			else
				*comp++ = ONE;
			count = 1;
			counter = comp;
			comp++;
			if (*poi == '^')
				*comp++ = *poi++;
			else
				*comp++ = '\0';
			while (end > poi) {
				if (*poi == ' ' || *poi == '\t')
					poi++;
				else if (*poi == '-') {
					cc = *(comp - 1);
					poi++;
					if ((ccm = hexchar()) < 0)
						return 1;
					while (cc <= ccm) {
						*comp++ = cc++;
						count++;
					}
					poi++;
					poi++;
				} else {
					if ((nr = hexchar()) < 0)
						return 1;
					count++;
					*comp++ = nr;
				}
			}
			poi++;
			*counter = count;
			if (*poi == '*')
				poi++;
		} else if (*poi == '"') {
			poi++;
			if (!(end = strchr(poi, '"'))) {
				/*
				   bvim_error(core, buf, "Missing '\"'");
				   return 1;
				 */
				end = poi + strlen(poi);
			}
			while (end > poi) {
				*comp++ = 1;
				*comp++ = 1;
				if (ignore_case)
					*comp++ = toupper(*poi++);
				else
					*comp++ = *poi++;
			}
			poi++;
		} else {
			if (*poi == '.') {
				if (*(poi + 1) == '*') {
					*comp++ = STAR;
					poi++;
				} else
					*comp++ = ONE;
				*comp++ = 0;
				poi++;
			} else {
				if ((nr = hexchar()) < 0)
					return 1;
				if (*poi == '*') {
					poi++;
					*comp++ = STAR;
				} else
					*comp++ = ONE;
				*comp++ = 1;
				*comp++ = nr;
			}
		}
	}
	*comp = END;
	smode = HEX;
	return 0;
}

int hexchar()
{
	unsigned int nr;
	char tmpbuf[3];

	if (isxdigit(*poi)) {
		tmpbuf[0] = *poi++;
		tmpbuf[1] = '\0';
		if (isxdigit(*poi))
			tmpbuf[1] = *poi++;
		tmpbuf[2] = '\0';
		sscanf(tmpbuf, "%2x", &nr);
		while (*poi == ' ' || *poi == '\t')
			poi++;
		return nr;
	} else {
		//bvim_error(core, buf, "Bad hex character@in expression");
		return -1;
	}
}