/*	$OpenBSD: softmagic.c,v 1.16 2010/01/17 20:36:21 chl Exp $ */
/*
 * Copyright (c) Ian F. Darwin 1986-1995.
 * Software written by Ian F. Darwin and others;
 * maintained 1995-present by Christos Zoulas and others.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice immediately at the beginning of the file, without modification,
 *    this list of conditions, and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
/*
 * softmagic - interpret variable magic from MAGIC
 */
#include <r_userconf.h>

#if !USE_LIB_MAGIC

#include <r_util.h>
#include "file.h"
#include "r_regex.h"
#include "r_util/r_time.h"

static void magic_debug(RMagic *ms, const char *fmt, ...) {
	if ((ms->flags & R_MAGIC_DEBUG) == 0) {
		return;
	}
	va_list ap;
	va_start (ap, fmt);
	char *msg = r_str_newvf (fmt, ap);
	va_end (ap);
	if (msg) {
		R_LOG_DEBUG ("%s", msg);
		free (msg);
	}
}

static bool magic_hasbytes(size_t nbytes, st64 offset, size_t need) {
	size_t uoffset;

	if (offset < 0) {
		return false;
	}
	uoffset = (size_t)offset;
	if (uoffset > nbytes) {
		return false;
	}
	return need <= nbytes - uoffset;
}

/*
 * Macro to give description string according to whether we want plain
 * text or MIME type
 */
#define R_MAGIC_DESC ((ms->flags & R_MAGIC_MIME)? m->mimetype: m->desc)

static bool desc_wants_string(const char *desc) {
	const char *p = desc;
	while ((p = strchr (p, '%'))) {
		p++;
		p += strspn (p, "-0123456789.");
		if (*p == 's') {
			return true;
		}
	}
	return false;
}

static st32 mprint(RMagic *ms, struct r_magic *m) {
	union VALUETYPE *const p = &ms->ms_value;
	const char *desc = R_MAGIC_DESC;
	const bool as_str = desc_wants_string (desc);
	char pp[ASCTIME_BUF_MAXLEN];
	char num[32];
	ut64 v;
	ut64 t;
	int rc;

	switch (m->type) {
	case FILE_BYTE:
		v = __magic_file_signextend (ms, m, (ut64)p->b);
		snprintf (num, sizeof (num), "%c", (ut8)v);
		rc = as_str? __magic_file_printf (ms, desc, num): __magic_file_printf (ms, desc, (ut8)v);
		t = ms->offset + sizeof (char);
		break;
	case FILE_SHORT:
	case FILE_BESHORT:
	case FILE_LESHORT:
		v = __magic_file_signextend (ms, m, (ut64)p->h);
		snprintf (num, sizeof (num), "%hu", (unsigned short)v);
		rc = as_str? __magic_file_printf (ms, desc, num): __magic_file_printf (ms, desc, (unsigned short)v);
		t = ms->offset + sizeof (short);
		break;
	case FILE_LONG:
	case FILE_BELONG:
	case FILE_LELONG:
	case FILE_MELONG:
		v = __magic_file_signextend (ms, m, (ut64)p->l);
		snprintf (num, sizeof (num), "%u", (ut32)v);
		rc = as_str? __magic_file_printf (ms, desc, num): __magic_file_printf (ms, desc, (ut32)v);
		t = ms->offset + sizeof (st32);
		break;
	case FILE_QUAD:
	case FILE_BEQUAD:
	case FILE_LEQUAD:
		v = __magic_file_signextend (ms, m, p->q);
		rc = __magic_file_printf (ms, desc, (ut64)v);
		t = ms->offset + sizeof (ut64);
		break;
	case FILE_STRING:
	case FILE_PSTRING:
	case FILE_BESTRING16:
	case FILE_LESTRING16:
		if (m->reln == '=' || m->reln == '!') {
			rc = __magic_file_printf (ms, desc, m->value.s);
			t = ms->offset + m->vallen;
		} else {
			if (*m->value.s == '\0') {
				p->s[strcspn (p->s, "\n")] = '\0';
			}
			rc = __magic_file_printf (ms, desc, p->s);
			t = ms->offset + strlen (p->s) + (m->type == FILE_PSTRING);
		}
		break;
	case FILE_DATE:
	case FILE_BEDATE:
	case FILE_LEDATE:
	case FILE_MEDATE:
		rc = __magic_file_printf (ms, desc, __magic_file_fmttime (p->l, 1, pp));
		t = ms->offset + sizeof (time_t);
		break;
	case FILE_LDATE:
	case FILE_BELDATE:
	case FILE_LELDATE:
	case FILE_MELDATE:
		rc = __magic_file_printf (ms, desc, __magic_file_fmttime (p->l, 0, pp));
		t = ms->offset + sizeof (time_t);
		break;
	case FILE_QDATE:
	case FILE_BEQDATE:
	case FILE_LEQDATE:
		rc = __magic_file_printf (ms, desc, __magic_file_fmttime ((ut32)p->q, 1, pp));
		t = ms->offset + sizeof (ut64);
		break;
	case FILE_QLDATE:
	case FILE_BEQLDATE:
	case FILE_LEQLDATE:
		rc = __magic_file_printf (ms, desc, __magic_file_fmttime ((ut32)p->q, 0, pp));
		t = ms->offset + sizeof (ut64);
		break;
	case FILE_FLOAT:
	case FILE_BEFLOAT:
	case FILE_LEFLOAT:
		snprintf (num, sizeof (num), "%g", p->f);
		rc = as_str? __magic_file_printf (ms, desc, num): __magic_file_printf (ms, desc, p->f);
		t = ms->offset + sizeof (float);
		break;
	case FILE_DOUBLE:
	case FILE_BEDOUBLE:
	case FILE_LEDOUBLE:
		snprintf (num, sizeof (num), "%g", p->d);
		rc = as_str? __magic_file_printf (ms, desc, num): __magic_file_printf (ms, desc, p->d);
		t = ms->offset + sizeof (double);
		break;
	case FILE_REGEX:
		{
			char *cp = r_str_ndup (ms->search.s, ms->search.rm_len);
			rc = __magic_file_printf (ms, desc, r_str_get (cp));
			free (cp);
			t = ms->search.offset + ((m->str_flags & REGEX_OFFSET_START)? 0: ms->search.rm_len);
		}
		break;
	case FILE_SEARCH:
		rc = __magic_file_printf (ms, desc, m->value.s);
		t = ms->search.offset + ((m->str_flags & REGEX_OFFSET_START)? 0: m->vallen);
		break;
	case FILE_DEFAULT:
		rc = __magic_file_printf (ms, desc, m->value.s);
		t = ms->offset;
		break;
	default:
		__magic_file_magerror (ms, "invalid m->type (%d) in mprint()", m->type);
		return -1;
	}
	return rc == -1? -1: (st32)t;
}

#define DO_CVT(fld, cast) \
	if (m->num_mask) \
		switch (m->mask_op & FILE_OPS_MASK) { \
		case FILE_OPAND: \
			p->fld &= cast m->num_mask; \
			break; \
		case FILE_OPOR: \
			p->fld |= cast m->num_mask; \
			break; \
		case FILE_OPXOR: \
			p->fld ^= cast m->num_mask; \
			break; \
		case FILE_OPADD: \
			p->fld += cast m->num_mask; \
			break; \
		case FILE_OPMINUS: \
			p->fld -= cast m->num_mask; \
			break; \
		case FILE_OPMULTIPLY: \
			p->fld *= cast m->num_mask; \
			break; \
		case FILE_OPDIVIDE: \
			p->fld /= cast m->num_mask; \
			break; \
		case FILE_OPMODULO: \
			p->fld %= cast m->num_mask; \
			break; \
		} \
	if (m->mask_op & FILE_OPINVERSE) \
	p->fld = ~p->fld

static void cvt_8(union VALUETYPE *p, const struct r_magic *m) {
	DO_CVT (b, (ut8));
}

static void cvt_16(union VALUETYPE *p, const struct r_magic *m) {
	DO_CVT (h, (ut16));
}

static void cvt_32(union VALUETYPE *p, const struct r_magic *m) {
	DO_CVT (l, (ut32));
}

static void cvt_64(union VALUETYPE *p, const struct r_magic *m) {
	DO_CVT (q, (ut64));
}

#define DO_CVT2(fld, cast) \
	if (m->num_mask) \
		switch (m->mask_op & FILE_OPS_MASK) { \
		case FILE_OPADD: \
			p->fld += cast m->num_mask; \
			break; \
		case FILE_OPMINUS: \
			p->fld -= cast m->num_mask; \
			break; \
		case FILE_OPMULTIPLY: \
			p->fld *= cast m->num_mask; \
			break; \
		case FILE_OPDIVIDE: \
			p->fld /= cast m->num_mask; \
			break; \
		}

static void cvt_float(union VALUETYPE *p, const struct r_magic *m) {
	DO_CVT2 (f, (float));
}

static void cvt_double(union VALUETYPE *p, const struct r_magic *m) {
	DO_CVT2 (d, (double));
}

static st32 apply_indir_op(st32 value, st32 off, int op) {
	if (off) {
		switch (op & FILE_OPS_MASK) {
		case FILE_OPAND: value &= off; break;
		case FILE_OPOR: value |= off; break;
		case FILE_OPXOR: value ^= off; break;
		case FILE_OPADD: value += off; break;
		case FILE_OPMINUS: value -= off; break;
		case FILE_OPMULTIPLY: value *= off; break;
		case FILE_OPDIVIDE: value /= off; break;
		case FILE_OPMODULO: value %= off; break;
		}
	}
	return (op & FILE_OPINVERSE)? ~value: value;
}

static st32 magic_melong(const ut8 *hl) {
	return (st32) ((hl[1] << 24) | (hl[0] << 16) | (hl[3] << 8) | hl[2]);
}

static bool magic_get_indir_value(st32 *out, const union VALUETYPE *p, int type) {
	switch (type) {
	case FILE_BYTE:
		*out = p->b;
		return true;
	case FILE_SHORT:
		*out = p->h;
		return true;
	case FILE_BESHORT:
		*out = (st16)r_read_be16 (p->hs);
		return true;
	case FILE_LESHORT:
		*out = (st16)r_read_le16 (p->hs);
		return true;
	case FILE_LONG:
		*out = p->l;
		return true;
	case FILE_BELONG:
		*out = (st32)r_read_be32 (p->hl);
		return true;
	case FILE_LELONG:
		*out = (st32)r_read_le32 (p->hl);
		return true;
	case FILE_MELONG:
		*out = magic_melong (p->hl);
		return true;
	default:
		return false;
	}
}

static void magic_rstrip_newline(char *s) {
	size_t len = strlen (s);
	if (len > 0 && s[len - 1] == '\n') {
		s[len - 1] = '\0';
	}
}

/*
 * Convert the byte order of the data we are looking at
 * While we're here, let's apply the mask operation
 *(unless you have a better idea)
 */
static int mconvert(RMagic *ms, struct r_magic *m) {
	union VALUETYPE *const p = &ms->ms_value;

	switch (m->type) {
	case FILE_BYTE:
		cvt_8 (p, m);
		return 1;
	case FILE_SHORT:
		cvt_16 (p, m);
		return 1;
	case FILE_LONG:
	case FILE_DATE:
	case FILE_LDATE:
		cvt_32 (p, m);
		return 1;
	case FILE_QUAD:
	case FILE_QDATE:
	case FILE_QLDATE:
		cvt_64 (p, m);
		return 1;
	case FILE_STRING:
	case FILE_BESTRING16:
	case FILE_LESTRING16:
		p->s[sizeof (p->s) - 1] = '\0';
		magic_rstrip_newline (p->s);
		return 1;
	case FILE_PSTRING:
		{
			char *ptr1 = p->s, *ptr2 = ptr1 + 1;
			size_t len = *p->s;
			if (len >= sizeof (p->s)) {
				len = sizeof (p->s) - 1;
			}
			while (len--) {
				*ptr1++ = *ptr2++;
			}
			*ptr1 = '\0';
			magic_rstrip_newline (p->s);
			return 1;
		}
	case FILE_BESHORT:
		p->h = (short)r_read_be16 (p->hs);
		cvt_16 (p, m);
		return 1;
	case FILE_BELONG:
	case FILE_BEDATE:
	case FILE_BELDATE:
		p->l = (st32)r_read_be32 (p->hl);
		cvt_32 (p, m);
		return 1;
	case FILE_BEQUAD:
	case FILE_BEQDATE:
	case FILE_BEQLDATE:
		p->q = r_read_be64 (p->hq);
		cvt_64 (p, m);
		return 1;
	case FILE_LESHORT:
		p->h = (short)r_read_le16 (p->hs);
		cvt_16 (p, m);
		return 1;
	case FILE_LELONG:
	case FILE_LEDATE:
	case FILE_LELDATE:
		p->l = (st32)r_read_le32 (p->hl);
		cvt_32 (p, m);
		return 1;
	case FILE_LEQUAD:
	case FILE_LEQDATE:
	case FILE_LEQLDATE:
		p->q = r_read_le64 (p->hq);
		cvt_64 (p, m);
		return 1;
	case FILE_MELONG:
	case FILE_MEDATE:
	case FILE_MELDATE:
		p->l = magic_melong (p->hl);
		cvt_32 (p, m);
		return 1;
	case FILE_FLOAT:
		cvt_float (p, m);
		return 1;
	case FILE_BEFLOAT:
		p->l = r_read_be32 (p->hl);
		cvt_float (p, m);
		return 1;
	case FILE_LEFLOAT:
		p->l = r_read_le32 (p->hl);
		cvt_float (p, m);
		return 1;
	case FILE_DOUBLE:
		cvt_double (p, m);
		return 1;
	case FILE_BEDOUBLE:
		p->q = r_read_be64 (p->hq);
		cvt_double (p, m);
		return 1;
	case FILE_LEDOUBLE:
		p->q = r_read_le64 (p->hq);
		cvt_double (p, m);
		return 1;
	case FILE_REGEX:
	case FILE_SEARCH:
	case FILE_DEFAULT:
		return 1;
	default:
		__magic_file_magerror (ms, "invalid type %d in mconvert()", m->type);
		return 0;
	}
}

static void magic_debug_dump(RMagic *ms, struct r_magic *m, ut32 offset, const union VALUETYPE *p) {
	if ((ms->flags & R_MAGIC_DEBUG) == 0) {
		return;
	}
	char *const escaped = r_str_escape_raw ((const ut8 *)p, (int)sizeof (*p));
	if (escaped) {
		magic_debug (ms, "mget @%u: %s", offset, escaped);
		free (escaped);
	} else {
		magic_debug (ms, "mget @%u", offset);
	}
	__magic_file_mdump (ms, m);
}

static int mcopy(RMagic *ms, union VALUETYPE *p, int type, int indir, const ut8 *s, ut32 offset, size_t nbytes, size_t linecnt) {
	// Search and regex types just point into the source buffer.
	if (indir == 0) {
		switch (type) {
		case FILE_SEARCH:
		case FILE_REGEX:
			if (!s || offset > nbytes) {
				ms->search.s = NULL;
				ms->search.s_len = 0;
				return 0;
			}
			{
				const char *buf = (const char *)s + offset;
				const char *end = (const char *)s + nbytes;
				const char *last = end;
				size_t lines = (type == FILE_REGEX)? linecnt: 0;
				// Regex tests only see the first linecnt lines
				for (; lines && buf < end; lines--) {
					const char *nl = memchr (buf, '\n', end - buf);
					if (!nl && !(nl = memchr (buf, '\r', end - buf))) {
						break;
					}
					last = nl;
					buf = nl + ((nl[0] == '\r' && nl + 1 < end && nl[1] == '\n')? 2: 1);
				}
				ms->search.s = (const char *)s + offset;
				ms->search.s_len = (lines? end: last) - ms->search.s;
				ms->search.offset = offset;
				ms->search.rm_len = 0;
			}
			return 0;
		case FILE_BESTRING16:
		case FILE_LESTRING16:
			{
				const ut8 *src = s + offset;
				const ut8 *esrc = s + nbytes;
				char *dst = p->s;
				char *edst = &p->s[sizeof (p->s) - 1];

				if (type == FILE_BESTRING16) {
					src++;
				}

				/* check for pointer overflow */
				if (src < s) {
					__magic_file_magerror (ms, "invalid offset %u in mcopy()", offset);
					return -1;
				}
				for (/*EMPTY*/; src < esrc; src += 2, dst++) {
					if (dst < edst) {
						*dst = *src;
					} else {
						break;
					}
					if (*dst == '\0') {
						if (type == FILE_BESTRING16? *(src - 1) != '\0': *(src + 1) != '\0') {
							*dst = ' ';
						}
					}
				}
				*edst = '\0';
				return 0;
			}
		case FILE_STRING: /* XXX - these two should not need */
		case FILE_PSTRING: /* to copy anything, but do anyway. */
		default:
			break;
		}
	}

	if (offset >= nbytes) {
		(void)memset (p, '\0', sizeof (*p));
		return 0;
	}
	nbytes = (nbytes - offset < sizeof (*p))? nbytes - offset: sizeof (*p);

	(void)memcpy (p, s + offset, nbytes);

	if (nbytes < sizeof (*p)) {
		(void)memset (((char *) (void *)p) + nbytes, '\0', sizeof (*p) - nbytes);
	}
	return 0;
}

static int mget(RMagic *ms, const ut8 *s, struct r_magic *m, size_t nbytes, unsigned int cont_level) {
	ut32 offset = ms->offset;
	const ut32 count = m->str_range;
	union VALUETYPE *const p = &ms->ms_value;

	if (mcopy (ms, p, m->type, m->flag & INDIR, s, offset, nbytes, count) == -1) {
		return -1;
	}

	magic_debug_dump (ms, m, offset, p);

	if (m->flag & INDIR) {
		int off = m->in_offset;
		if (m->in_op & FILE_OPINDIRECT) {
			st64 qoff = (st64)offset + off;
			if (!magic_hasbytes (nbytes, qoff, file_magic_type_bytes (m, m->in_type))) {
				return 0;
			}
			const union VALUETYPE *const q =
				((const void *) (s + (size_t)qoff));
			st32 qvalue;
			if (magic_get_indir_value (&qvalue, q, m->in_type)) {
				off = qvalue;
			}
		}
		if (!magic_hasbytes (nbytes, offset, file_magic_type_bytes (m, m->in_type))) {
			return 0;
		}
		st32 pvalue;
		if (magic_get_indir_value (&pvalue, p, m->in_type)) {
			off = apply_indir_op (pvalue, off, m->in_op);
		}
		if (off < 0) {
			return 0;
		}
		offset = (ut32)off;

		if (m->flag & INDIROFFADD) {
			// relative offsets are invalid at level 0, there is no
			// previous match to add to (the parser only warns)
			if (cont_level == 0) {
				return 0;
			}
			st64 noff = (st64)offset + ms->c.li[cont_level - 1].off;
			if (noff < 0) {
				return 0;
			}
			offset = (ut32)noff;
		}
		if (mcopy (ms, p, m->type, 0, s, offset, nbytes, count) == -1) {
			return -1;
		}
		ms->offset = offset;

		magic_debug_dump (ms, m, offset, p);
	}

	/* Verify we have enough data to match magic type */
	if (m->type != FILE_DEFAULT && !magic_hasbytes (nbytes, offset, file_magic_type_bytes (m, m->type))) {
		return 0;
	}
	return mconvert (ms, m);
}

static ut64 file_strncmp(const char *s1, const char *s2, size_t len, ut32 flags) {
	// Compare unsigned bytes so ctype calls stay valid.
	const ut8 *a = (const ut8 *)s1;
	const ut8 *b = (const ut8 *)s2;
	ut64 v;

	// Match strncmp semantics, but ignore embedded NULs.
	v = 0;
	if (0L == flags) { /* normal string: do it fast */
		while (len-- > 0) {
			if ((v = *b++ - *a++) != '\0') {
				break;
			}
		}
	} else { /* combine the others */
		while (len-- > 0) {
			if ((flags & STRING_IGNORE_LOWERCASE) &&
				islower (*a)) {
				if ((v = tolower (*b++) - *a++) != '\0') {
					break;
				}
			} else if ((flags & STRING_IGNORE_UPPERCASE) && isupper (*a)) {
				if ((v = toupper (*b++) - *a++) != '\0') {
					break;
				}
			} else if ((flags & STRING_COMPACT_BLANK) && isspace (*a)) {
				a++;
				if (isspace (*b++)) {
					while (isspace (*b)) {
						b++;
					}
				} else {
					v = 1;
					break;
				}
			} else if ((flags & STRING_COMPACT_OPTIONAL_BLANK) && isspace (*a)) {
				a++;
				while (isspace (*b)) {
					b++;
				}
			} else {
				if ((v = *b++ - *a++) != '\0') {
					break;
				}
			}
		}
	}
	return v;
}

static int magiccheck(RMagic *ms, struct r_magic *m, const RRegex *rx) {
	ut64 l = m->value.q;
	ut64 v;
	float fl, fv;
	double dl, dv;
	int matched;
	union VALUETYPE *const p = &ms->ms_value;

	switch (m->type) {
	case FILE_BYTE:
		v = p->b;
		break;
	case FILE_SHORT:
	case FILE_BESHORT:
	case FILE_LESHORT:
		v = p->h;
		break;
	case FILE_LONG:
	case FILE_BELONG:
	case FILE_LELONG:
	case FILE_MELONG:
	case FILE_DATE:
	case FILE_BEDATE:
	case FILE_LEDATE:
	case FILE_MEDATE:
	case FILE_LDATE:
	case FILE_BELDATE:
	case FILE_LELDATE:
	case FILE_MELDATE:
		v = p->l;
		break;
	case FILE_QUAD:
	case FILE_LEQUAD:
	case FILE_BEQUAD:
	case FILE_QDATE:
	case FILE_BEQDATE:
	case FILE_LEQDATE:
	case FILE_QLDATE:
	case FILE_BEQLDATE:
	case FILE_LEQLDATE:
		v = p->q;
		break;
	case FILE_FLOAT:
	case FILE_BEFLOAT:
	case FILE_LEFLOAT:
		fl = m->value.f;
		fv = p->f;
		switch (m->reln) {
		case 'x': matched = 1; break;
		case '!': matched = fv != fl; break;
		case '=': matched = fv == fl; break;
		case '>': matched = fv > fl; break;
		case '<': matched = fv < fl; break;
		default:
			__magic_file_magerror (ms, "cannot happen with float: invalid relation `%c'", m->reln);
			return -1;
		}
		return matched;
	case FILE_DOUBLE:
	case FILE_BEDOUBLE:
	case FILE_LEDOUBLE:
		dl = m->value.d;
		dv = p->d;
		switch (m->reln) {
		case 'x': matched = 1; break;
		case '!': matched = dv != dl; break;
		case '=': matched = dv == dl; break;
		case '>': matched = dv > dl; break;
		case '<': matched = dv < dl; break;
		default:
			__magic_file_magerror (ms, "cannot happen with double: invalid relation `%c'", m->reln);
			return -1;
		}
		return matched;
	case FILE_DEFAULT:
		l = 0;
		v = 0;
		break;
	case FILE_STRING:
	case FILE_PSTRING:
	case FILE_BESTRING16:
	case FILE_LESTRING16:
		l = 0;
		v = file_strncmp (m->value.s, p->s, (size_t)m->vallen, file_magic_type_is_string16 (m->type)? 0: m->str_flags);
		break;
	case FILE_SEARCH: { /* search ms->search.s for the string m->value.s */
		size_t idx;

		if (!ms->search.s) {
			return 0;
		}

		const size_t slen = R_MIN (m->vallen, sizeof (m->value.s));
		l = 0;
		v = 0;

		for (idx = 0; m->str_range == 0 || idx < m->str_range; idx++) {
			if (slen > ms->search.s_len || idx > ms->search.s_len - slen) {
				break;
			}
			v = file_strncmp (m->value.s, ms->search.s + idx, slen, m->str_flags);
			if (v == 0) { /* found match */
				ms->search.offset += idx;
				break;
			}
		}
		break;
	}
	case FILE_REGEX:
		{
			RRegexMatch pmatch[1] = {{ .rm_so = 0, .rm_eo = ms->search.s_len }};
			if (!ms->search.s || !rx) {
				return 0;
			}
			const int rc = r_regex_exec (rx, ms->search.s, 1, pmatch, R_REGEX_STARTEND);
			if (rc && rc != R_REGEX_NOMATCH) {
				__magic_file_magerror (ms, "regexec error %d", rc);
				return -1;
			}
			l = 0;
			v = rc == R_REGEX_NOMATCH;
			if (!v) {
				ms->search.s += pmatch[0].rm_so;
				ms->search.offset += pmatch[0].rm_so;
				ms->search.rm_len = pmatch[0].rm_eo - pmatch[0].rm_so;
			}
			break;
		}
	default:
		__magic_file_magerror (ms, "invalid type %d in magiccheck()", m->type);
		return -1;
	}

	v = __magic_file_signextend (ms, m, v);
	const bool is_unsigned = m->flag & UNSIGNED;
	switch (m->reln) {
	case 'x':
		matched = 1;
		break;
	case '!':
		matched = v != l;
		break;
	case '=':
		matched = v == l;
		break;
	case '>':
		matched = is_unsigned? v > l: (st64)v > (st64)l;
		break;
	case '<':
		matched = is_unsigned? v < l: (st64)v < (st64)l;
		break;
	case '&':
		matched = (v & l) == l;
		break;
	case '^':
		matched = (v & l) != l;
		break;
	default:
		__magic_file_magerror (ms, "cannot happen: invalid relation `%c'", m->reln);
		return -1;
	}
	magic_debug (ms, "0x%" PFMT64x " %c 0x%" PFMT64x " = %d", v, m->reln, l, matched);
	return matched;
}

static int print_sep(RMagic *ms, int firstline) {
	return firstline? 0: __magic_file_printf (ms, "\n- ");
}

/*
 * Go through the whole list, stopping if you find a match.  Process all
 * the continuations of that match before returning.
 *
 * We support multi-level continuations:
 *
 *	At any time when processing a successful top-level match, there is a
 *	current continuation level; it represents the level of the last
 *	successfully matched continuation.
 *
 *	Continuations above that level are skipped as, if we see one, it
 *	means that the continuation that controls them - i.e, the
 *	lower-level continuation preceding them - failed to match.
 *
 *	Continuations below that level are processed as, if we see one,
 *	it means we've finished processing or skipping higher-level
 *	continuations under the control of a successful or unsuccessful
 *	lower-level continuation, and are now seeing the next lower-level
 *	continuation and should process it.  The current continuation
 *	level reverts to the level of the one we're seeing.
 *
 *	Continuations at the current level are processed as, if we see
 *	one, there's no lower-level continuation that may have failed.
 *
 *	If a continuation matches, we bump the current continuation level
 *	so that higher-level continuations are processed.
 */
static bool root_prefix_matches(const struct r_magic_root *root, const ut8 *s, size_t nbytes) {
	return !root->prefix_len || (magic_hasbytes (nbytes, root->offset, root->prefix_len) && !memcmp (s + root->offset, root->prefix, root->prefix_len));
}

// Returns -1 on error, 0 on mismatch, 1 on match and 2 when the data is too short
static int mtest(RMagic *ms, const struct mlist *ml, ut32 idx, const ut8 *s, size_t nbytes, unsigned int cont_level) {
	struct r_magic *m = &ml->magic[idx];
	const int got = mget (ms, s, m, nbytes, cont_level);
	if (got <= 0) {
		return got? -1: (m->reln == '!')? 1: 2;
	}
	return magiccheck (ms, m, ml->rx? ml->rx[idx]: NULL);
}

static int match(RMagic *ms, const struct mlist *ml, const ut8 *s, size_t nbytes, int mode) {
	int returnval = 0;
	ut32 i;

	if (__magic_file_check_mem (ms, 0) == -1) {
		return -1;
	}
	// Merge the roots indexed by the first byte with the unindexed ones in database order
	const struct r_magic_root *a = ml->roots + ml->bucket[nbytes? s[0]: 256];
	const struct r_magic_root *a_end = ml->roots + (nbytes? ml->bucket[s[0] + 1]: ml->bucket[256]);
	const struct r_magic_root *b = ml->roots + ml->bucket[256];
	const struct r_magic_root *b_end = ml->roots + ml->bucket[257];
	while (a < a_end || b < b_end) {
		const struct r_magic_root *root = (b == b_end || (a < a_end && a->start < b->start))? a++: b++;
		if (root->bintest != mode || !root_prefix_matches (root, s, nbytes)) {
			continue;
		}
		struct r_magic *m = &ml->magic[root->start];
		ms->offset = m->offset;
		ms->line = m->lineno;
		int ret = mtest (ms, ml, root->start, s, nbytes, 0);
		if (ret == -1) {
			return -1;
		}
		if (ret != 1) {
			continue;
		}
		const bool firstline = r_strbuf_is_empty (&ms->o.sb);
		bool printed_something = false;
		bool need_separator = false;
		if (*R_MAGIC_DESC) {
			need_separator = true;
			printed_something = true;
			if (print_sep (ms, firstline) == -1) {
				return -1;
			}
		}
		if ((ms->c.li[0].off = mprint (ms, m)) == -1) {
			return -1;
		}
		unsigned int cont_level = 1;
		if (__magic_file_check_mem (ms, cont_level) == -1) {
			return -1;
		}
		for (i = root->start + 1; i < root->end; i++) {
			m = &ml->magic[i];
			ms->line = m->lineno;
			if (cont_level < m->cont_level) {
				continue;
			}
			// Drop back to the level of this continuation
			cont_level = m->cont_level;
			struct level_info *li = &ms->c.li[cont_level];
			ms->offset = m->offset;
			if (m->flag & OFFADD) {
				ms->offset += ms->c.li[cont_level - 1].off;
			}
			if ((m->cond == COND_ELSE || m->cond == COND_ELIF) && li->last_match == 1) {
				continue;
			}
			ret = mtest (ms, ml, i, s, nbytes, cont_level);
			if (ret == -1) {
				return -1;
			}
			if (ret == 2) {
				continue;
			}
			li->last_match = ret;
			if (!ret) {
				continue;
			}
			if (m->type != FILE_DEFAULT) {
				li->got_match = 1;
			} else if (li->got_match) {
				li->got_match = 0;
				continue;
			}
			if (*R_MAGIC_DESC) {
				if (!printed_something) {
					printed_something = true;
					if (print_sep (ms, firstline) == -1) {
						return -1;
					}
				}
				if (need_separator && !(m->flag & NOSPACE) && __magic_file_printf (ms, " ") == -1) {
					return -1;
				}
				need_separator = true;
			}
			if ((li->off = mprint (ms, m)) == -1) {
				return -1;
			}
			// Process any deeper continuations
			if (__magic_file_check_mem (ms, ++cont_level) == -1) {
				return -1;
			}
		}
		if (printed_something) {
			returnval = 1;
			if (!(ms->flags & R_MAGIC_CONTINUE)) {
				break;
			}
		}
	}
	return returnval;
}

int __magic_file_softmagic(RMagic *ms, const ut8 *buf, size_t nbytes, int mode) {
	struct mlist *ml;
	int rv = 0;
	R_VEC_FOREACH (&ms->mlist, ml) {
		const int ret = match (ms, ml, buf, nbytes, mode);
		if (ret == -1) {
			return -1;
		}
		if (ret) {
			rv = 1;
			if (!(ms->flags & R_MAGIC_CONTINUE)) {
				break;
			}
		}
	}
	return rv;
}
#endif