filefrag.c (frag_report): Automatically detect files that are

	stored using the new experimental file fragments format,
	and use the non-ext2 algorithm for determing the number of
	extents.  Avoid reporting a false discontinuity if there
	is a non-allocated block (or extent) at the beginning of
	the file.

diff --git a/misc/ChangeLog b/misc/ChangeLog
index b94adb3..e1a6da8 100644 (file)
--- a/misc/ChangeLog
+++ b/misc/ChangeLog
@@ -1,3 +1,12 @@
+2005-03-18  Theodore Ts'o  <tytso@mit.edu>
+
+       * filefrag.c (frag_report): Automatically detect files that are
+               stored using the new experimental file fragments format,
+               and use the non-ext2 algorithm for determing the number of
+               extents.  Avoid reporting a false discontinuity if there
+               is a non-allocated block (or extent) at the beginning of
+               the file.
+
 2006-02-05  Theodore Ts'o  <tytso@mit.edu>
 
        * Release of E2fsprogs 1.36

diff --git a/misc/filefrag.c b/misc/filefrag.c
index 8463efd..1ba7cc6 100644 (file)
--- a/misc/filefrag.c
+++ b/misc/filefrag.c
@@ -44,6 +44,9 @@ int verbose = 0;
 #define FIBMAP    _IO(0x00,1)  /* bmap access */
 #define FIGETBSZ   _IO(0x00,2) /* get the block size used for bmap */
 
+#define EXT3_EXTENTS_FL                        0x00080000 /* Inode uses extents */
+#define        EXT3_IOC_GETFLAGS               _IOR('f', 1, long)
+
 static unsigned long get_bmap(int fd, unsigned long block)
 {
        int     ret;
@@ -72,6 +75,7 @@ static void frag_report(const char *filename)
        long            cylgroups;
        int             discont = 0, expected;
        int             is_ext2 = 0;
+       unsigned int    flags;
 
        if (statfs(filename, &fsinfo) < 0) {
                perror("statfs");
@@ -106,6 +110,15 @@ static void frag_report(const char *filename)
                close(fd);
                return;
        }
+       if (ioctl(fd, EXT3_IOC_GETFLAGS, &flags) < 0) {
+               perror("EXT3_IOC_GETFLAGS");
+               close(fd);
+               return;
+       }
+       if (flags & EXT3_EXTENTS_FL) {
+               printf("File is stored in extents format\n");
+               is_ext2 = 0;
+       }
        if (verbose)
                printf("Blocksize of file %s is %ld\n", filename, bs);
        bpib = bs / 4;
@@ -126,14 +139,15 @@ static void frag_report(const char *filename)
                                last_block++;
                }
                block = get_bmap(fd, i);
-               if (i && block && (block != last_block +1) ) {
+               if (block == 0)
+                       continue;
+               if (last_block && (block != last_block +1) ) {
                        if (verbose)
                                printf("Discontinuity: Block %ld is at %ld (was %ld)\n",
                                       i, block, last_block);
                        discont++;
                }
-               if (block)
-                       last_block = block;
+               last_block = block;
        }
        if (discont==0)
                printf("%s: 1 extent found", filename);