Adding upstream version 3.5.upstream/3.5upstream

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

1 files changed, 279 insertions, 0 deletions

diff --git a/util.c b/util.c
new file mode 100644
index 0000000..2770b1d
--- /dev/null
+++ b/util.c
@@ -0,0 +1,279 @@
+/*
+ * Common "util" functions
+ * This file is part of the dmidecode project.
+ *
+ *   Copyright (C) 2002-2018 Jean Delvare <jdelvare@suse.de>
+ *
+ *   This program 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 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program 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 this program; if not, write to the Free Software
+ *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ *
+ *   For the avoidance of doubt the "preferred form" of this code is one which
+ *   is in an open unpatent encumbered format. Where cryptographic key signing
+ *   forms part of the process of creating an executable the information
+ *   including keys needed to generate an equivalently functional executable
+ *   are deemed to be part of the source code.
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include "config.h"
+
+#ifdef USE_MMAP
+#include <sys/mman.h>
+#ifndef MAP_FAILED
+#define MAP_FAILED ((void *) -1)
+#endif /* !MAP_FAILED */
+#endif /* USE MMAP */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <fcntl.h>
+#include <errno.h>
+
+#include "types.h"
+#include "util.h"
+
+static int myread(int fd, u8 *buf, size_t count, const char *prefix)
+{
+	ssize_t r = 1;
+	size_t r2 = 0;
+
+	while (r2 != count && r != 0)
+	{
+		r = read(fd, buf + r2, count - r2);
+		if (r == -1)
+		{
+			if (errno != EINTR)
+			{
+				perror(prefix);
+				return -1;
+			}
+		}
+		else
+			r2 += r;
+	}
+
+	if (r2 != count)
+	{
+		fprintf(stderr, "%s: Unexpected end of file\n", prefix);
+		return -1;
+	}
+
+	return 0;
+}
+
+int checksum(const u8 *buf, size_t len)
+{
+	u8 sum = 0;
+	size_t a;
+
+	for (a = 0; a < len; a++)
+		sum += buf[a];
+	return (sum == 0);
+}
+
+/*
+ * Reads all of file from given offset, up to max_len bytes.
+ * A buffer of at most max_len bytes is allocated by this function, and
+ * needs to be freed by the caller.
+ * This provides a similar usage model to mem_chunk()
+ *
+ * Returns a pointer to the allocated buffer, or NULL on error, and
+ * sets max_len to the length actually read.
+ */
+void *read_file(off_t base, size_t *max_len, const char *filename)
+{
+	struct stat statbuf;
+	int fd;
+	u8 *p;
+
+	/*
+	 * Don't print error message on missing file, as we will try to read
+	 * files that may or may not be present.
+	 */
+	if ((fd = open(filename, O_RDONLY)) == -1)
+	{
+		if (errno != ENOENT)
+			perror(filename);
+		return NULL;
+	}
+
+	/*
+	 * Check file size, don't allocate more than can be read.
+	 */
+	if (fstat(fd, &statbuf) == 0)
+	{
+		if (base >= statbuf.st_size)
+		{
+			fprintf(stderr, "%s: Can't read data beyond EOF\n",
+				filename);
+			p = NULL;
+			goto out;
+		}
+		if (*max_len > (size_t)statbuf.st_size - base)
+			*max_len = statbuf.st_size - base;
+	}
+
+	if ((p = malloc(*max_len)) == NULL)
+	{
+		perror("malloc");
+		goto out;
+	}
+
+	if (lseek(fd, base, SEEK_SET) == -1)
+	{
+		fprintf(stderr, "%s: ", filename);
+		perror("lseek");
+		goto err_free;
+	}
+
+	if (myread(fd, p, *max_len, filename) == 0)
+		goto out;
+
+err_free:
+	free(p);
+	p = NULL;
+
+out:
+	if (close(fd) == -1)
+		perror(filename);
+
+	return p;
+}
+
+#ifdef USE_MMAP
+static void safe_memcpy(void *dest, const void *src, size_t n)
+{
+#ifdef USE_SLOW_MEMCPY
+	size_t i;
+
+	for (i = 0; i < n; i++)
+		*((u8 *)dest + i) = *((const u8 *)src + i);
+#else
+	memcpy(dest, src, n);
+#endif /* USE_SLOW_MEMCPY */
+}
+#endif /* USE_MMAP */
+
+/*
+ * Copy a physical memory chunk into a memory buffer.
+ * This function allocates memory.
+ */
+void *mem_chunk(off_t base, size_t len, const char *devmem)
+{
+	struct stat statbuf;
+	void *p = NULL;
+	int fd;
+#ifdef USE_MMAP
+	off_t mmoffset;
+	void *mmp;
+#endif
+
+	/*
+	 * Safety check: if running as root, devmem is expected to be a
+	 * character device file.
+	 */
+	if ((fd = open(devmem, O_RDONLY)) == -1
+	 || fstat(fd, &statbuf) == -1
+	 || (geteuid() == 0 && !S_ISCHR(statbuf.st_mode)))
+	{
+		fprintf(stderr, "Can't read memory from %s\n", devmem);
+		if (fd == -1)
+			return NULL;
+		goto out;
+	}
+
+	if ((p = malloc(len)) == NULL)
+	{
+		perror("malloc");
+		goto out;
+	}
+
+#ifdef USE_MMAP
+	/*
+	 * mmap() will fail with SIGBUS if trying to map beyond the end of
+	 * the file.
+	 */
+	if (S_ISREG(statbuf.st_mode) && base + (off_t)len > statbuf.st_size)
+	{
+		fprintf(stderr, "mmap: Can't map beyond end of file %s\n",
+			devmem);
+		goto err_free;
+	}
+
+#ifdef _SC_PAGESIZE
+	mmoffset = base % sysconf(_SC_PAGESIZE);
+#else
+	mmoffset = base % getpagesize();
+#endif /* _SC_PAGESIZE */
+	/*
+	 * Please note that we don't use mmap() for performance reasons here,
+	 * but to workaround problems many people encountered when trying
+	 * to read from /dev/mem using regular read() calls.
+	 */
+	mmp = mmap(NULL, mmoffset + len, PROT_READ, MAP_SHARED, fd, base - mmoffset);
+	if (mmp == MAP_FAILED)
+		goto try_read;
+
+	safe_memcpy(p, (u8 *)mmp + mmoffset, len);
+
+	if (munmap(mmp, mmoffset + len) == -1)
+	{
+		fprintf(stderr, "%s: ", devmem);
+		perror("munmap");
+	}
+
+	goto out;
+
+try_read:
+#endif /* USE_MMAP */
+	if (lseek(fd, base, SEEK_SET) == -1)
+	{
+		fprintf(stderr, "%s: ", devmem);
+		perror("lseek");
+		goto err_free;
+	}
+
+	if (myread(fd, p, len, devmem) == 0)
+		goto out;
+
+err_free:
+	free(p);
+	p = NULL;
+
+out:
+	if (close(fd) == -1)
+		perror(devmem);
+
+	return p;
+}
+
+/* Returns end - start + 1, assuming start < end */
+u64 u64_range(u64 start, u64 end)
+{
+	u64 res;
+
+	res.h = end.h - start.h;
+	res.l = end.l - start.l;
+
+	if (end.l < start.l)
+		res.h--;
+	if (++res.l == 0)
+		res.h++;
+
+	return res;
+}