Adding upstream version 1:5.45.upstream/1%5.45upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 209 insertions, 0 deletions

diff --git a/src/is_simh.c b/src/is_simh.c
new file mode 100644
index 0000000..4e78173
--- /dev/null
+++ b/src/is_simh.c
@@ -0,0 +1,209 @@
+/*-
+ * Copyright (c) 2023 Christos Zoulas
+ * All rights reserved.
+ *
+ * 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, 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
+ */
+
+/*
+ * Parse SIM-H tape files
+ * http://simh.trailing-edge.com/docs/simh_magtape.pdf
+ */
+
+#ifndef TEST
+#include "file.h"
+
+#ifndef lint
+FILE_RCSID("@(#)$File: is_simh.c,v 1.10 2023/07/27 19:39:55 christos Exp $")
+#endif
+
+#include <string.h>
+#include <stddef.h>
+#include "magic.h"
+#else
+#include <stdint.h>
+#include <sys/types.h>
+#include <string.h>
+#include <stddef.h>
+#define CAST(a, b) (a)(b)
+#endif
+
+
+#ifdef DEBUG
+#include <stdio.h>
+#define DPRINTF(fmt, ...) printf(fmt, __VA_ARGS__)
+#else
+#define DPRINTF(fmt, ...)
+#endif
+
+/*
+ * if SIMH_TAPEMARKS == 0:
+ *	check all the records and tapemarks
+ * otherwise:
+ *	check only up-to the number of tapemarks specified
+ */
+#ifndef SIMH_TAPEMARKS
+#define SIMH_TAPEMARKS 10
+#endif
+
+typedef union {
+	char s[4];
+	uint32_t u;
+} myword; 
+
+static myword simh_bo;
+
+#define NEED_SWAP	(simh_bo.u == CAST(uint32_t, 0x01020304))
+
+/*
+ * swap an int
+ */
+static uint32_t
+swap4(uint32_t sv)
+{
+	myword d, s;
+	s.u = sv;
+	d.s[0] = s.s[3];
+	d.s[1] = s.s[2];
+	d.s[2] = s.s[1];
+	d.s[3] = s.s[0];
+	return d.u;
+}
+
+
+static uint32_t
+getlen(const unsigned char **uc)
+{
+	uint32_t n;
+	memcpy(&n, *uc, sizeof(n));
+	*uc += sizeof(n);
+	if (NEED_SWAP)
+		n = swap4(n);
+	if (n == 0xffffffff)	/* check for End of Medium */
+		return n;
+	n &= 0x00ffffff;	/* keep only the record len */
+	if (n & 1)
+		n++;
+	return n;
+}
+
+static int
+simh_parse(const unsigned char *uc, const unsigned char *ue)
+{
+	uint32_t nbytes, cbytes;
+	const unsigned char *orig_uc = uc;
+	size_t nt = 0, nr = 0;
+
+	(void)memcpy(simh_bo.s, "\01\02\03\04", 4);
+
+	while (ue - uc >= CAST(ptrdiff_t, sizeof(nbytes))) {
+		nbytes = getlen(&uc);
+		if ((nt > 0 || nr > 0) && nbytes == 0xFFFFFFFF)
+			/* EOM after at least one record or tapemark */
+			break;
+		if (nbytes == 0) {
+			nt++;	/* count tapemarks */
+#if SIMH_TAPEMARKS
+			if (nt == SIMH_TAPEMARKS)
+				break;
+#endif
+			continue;
+		}
+		/* handle a data record */
+		uc += nbytes;
+		if (ue - uc < CAST(ptrdiff_t, sizeof(nbytes)))
+			break;
+		cbytes = getlen(&uc);
+		if (nbytes != cbytes)
+			return 0;
+		nr++;
+	}
+	if (nt * sizeof(uint32_t) == CAST(size_t, uc - orig_uc))
+		return 0;	/* All examined data was tapemarks (0) */
+	if (nr == 0)		/* No records */
+		return 0;
+	return 1;
+}
+
+#ifndef TEST
+int
+file_is_simh(struct magic_set *ms, const struct buffer *b)
+{
+	const unsigned char *uc = CAST(const unsigned char *, b->fbuf);
+	const unsigned char *ue = uc + b->flen;
+	int mime = ms->flags & MAGIC_MIME;
+
+	if ((ms->flags & (MAGIC_APPLE|MAGIC_EXTENSION)) != 0)
+		return 0;
+
+	if (!simh_parse(uc, ue))
+		return 0;
+
+	if (mime == MAGIC_MIME_ENCODING)
+		return 1;
+
+	if (mime) {
+		if (file_printf(ms, "application/SIMH-tape-data") == -1)
+			return -1;
+		return 1;
+	}
+
+	if (file_printf(ms, "SIMH tape data") == -1)
+		return -1;
+
+	return 1;
+}
+
+#else
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <err.h>
+
+int
+main(int argc, char *argv[])
+{
+	int fd;
+	struct stat st;
+	unsigned char *p;
+
+	if ((fd = open(argv[1], O_RDONLY)) == -1)
+		err(EXIT_FAILURE, "Can't open `%s'", argv[1]);
+
+	if (fstat(fd, &st) == -1)
+		err(EXIT_FAILURE, "Can't stat `%s'", argv[1]);
+
+	if ((p = CAST(char *, malloc(st.st_size))) == NULL)
+		err(EXIT_FAILURE, "Can't allocate %jd bytes",
+		    (intmax_t)st.st_size);
+	if (read(fd, p, st.st_size) != st.st_size)
+		err(EXIT_FAILURE, "Can't read %jd bytes",
+		    (intmax_t)st.st_size);
+	printf("is simh %d\n", simh_parse(p, p + st.st_size));
+	return 0;
+}
+#endif