Imported reiserfsprogs-3.6.20

libmisc/device.c

@@ -0,0 +1,145 @@
+/*
+ * Copyright 1996-2004 by Hans Reiser, licensing governed by 
+ * reiserfsprogs/README
+ */
+
+#ifdef HAVE_CONFIG_H
+#  include <config.h>
+#endif
+
+#include "misc/device.h"
+#include "misc/misc.h"
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mount.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+
+#define MISC_DEVICE_STAT(Field, Type)					\
+Type misc_device_##Field(char *device) {				\
+	struct stat st;							\
+									\
+	if (stat(device, &st) == 0)					\
+		return st.st_##Field;					\
+									\
+	fprintf(stderr, "Stat of the device '%s' failed.\n", device);	\
+	return (Type)-1;						\
+}
+
+MISC_DEVICE_STAT(mode, mode_t);
+MISC_DEVICE_STAT(rdev, dev_t);
+
+int misc_device_valid_offset(int fd, long long int offset) {
+    long long int res;
+    char ch;
+
+    /*res = reiserfs_llseek (fd, offset, 0);*/
+    res = lseek (fd, (off_t)offset, SEEK_SET);
+    if (res < 0)
+	return 0;
+
+    /* if (read (fd, &ch, 1) < 0) does not wirk on files */
+    if (read (fd, &ch, 1) < 1)
+	return 0;
+
+
+    return 1;
+}
+
+/* To not have problem with last sectors on the block device when switching 
+   to smaller one. */
+#define MAX_BS (64 * 1024)
+
+/* calculates number of blocks in a file. Returns 0 for "sparse"
+   regular files and files other than regular files and block devices */
+unsigned long misc_device_count_blocks (char * filename, int blocksize)
+{
+    long long int high, low;
+    int fd;
+
+    fd = open (filename, O_RDONLY);
+    if (fd == -1) {
+	fprintf(stderr, "Failed to open '%s': %s.\n", filename, strerror(errno));
+	return 0;
+    }
+
+    if (!S_ISBLK(misc_device_mode(filename)) && 
+	!S_ISREG(misc_device_mode(filename))) 
+    {
+	close(fd);
+	return 0;
+    }
+
+#ifdef BLKGETSIZE64
+    {
+	unsigned long long size;
+	unsigned long sz;
+	
+	if (ioctl (fd, BLKGETSIZE64, &size) >= 0) {
+	    size = (size / MAX_BS) * MAX_BS / blocksize;
+	    sz = size;
+	    if ((unsigned long long)sz != size)
+		    misc_die ("misc_device_count_blocks: block device too large");
+
+	    close(fd);
+	    return sz;
+	}
+    }
+#endif
+
+
+#ifdef BLKGETSIZE
+    {
+	unsigned long long size;
+	unsigned long sz;
+	
+	if (ioctl (fd, BLKGETSIZE, &sz) >= 0) {
+	    size = sz;
+
+	    close(fd);
+	    return (size * 512 / MAX_BS) * MAX_BS / blocksize;
+	}
+    }
+#endif
+
+    low = 0;
+    for( high = 1; misc_device_valid_offset (fd, high); high *= 2 )
+	low = high;
+    while (low < high - 1) {
+	const long long int mid = ( low + high ) / 2;
+
+	if (misc_device_valid_offset (fd, mid))
+	    low = mid;
+	else
+	    high = mid;
+    }
+    
+    misc_device_valid_offset (fd, 0);
+
+    close (fd);
+    return (low + 1) * MAX_BS / MAX_BS / blocksize;
+}
+
+char misc_device_typec (unsigned short mode)
+{
+    if (S_ISBLK ((mode_t)mode))
+	return 'b';
+    if (S_ISCHR (mode))
+	return 'c';
+    if (S_ISDIR (mode))
+	return 'd';
+    if (S_ISREG (mode))
+	return '-';
+    if (S_ISFIFO (mode))
+	return 'p';
+    if (S_ISLNK (mode))
+	return 'l';
+    if (S_ISSOCK (mode))
+	return 's';
+    return '?';
+}
+