e2image: clean up progress reporting

The old progress reporting code would crash on small file systems.
For example:

    cp /dev/null /tmp/foo.img
    mke2fs -t ext4 -F /tmp/foo.img 100
    e2image -o 0 -O 4096 -rap /tmp/foo.img

Fix this, and while we're at it, factor out the code to make it easier
to read and maintain.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/misc/e2image.c b/misc/e2image.c
index 5e38bb0..352fbb2 100644 (file)
--- a/misc/e2image.c
+++ b/misc/e2image.c
@@ -540,6 +540,16 @@ static void sigint_handler(int unused EXT2FS_ATTR((unused)))
        signal (SIGINT, SIG_DFL);
 }
 
+#define calc_percent(a, b) ((int) ((100.0 * (((float) (a)) / \
+                                            ((float) (b)))) + 0.5))
+#define calc_rate(t, b, d) (((float)(t) / ((1024 * 1024) / (b))) / (d))
+
+static int print_progress(blk64_t num, blk64_t total)
+{
+       return printf(_("%llu / %llu blocks (%d%%)"), num, total,
+                     calc_percent(num, total));
+}
+
 static void output_meta_data_blocks(ext2_filsys fs, int fd, int flags)
 {
        errcode_t       retval;
@@ -566,10 +576,7 @@ static void output_meta_data_blocks(ext2_filsys fs, int fd, int flags)
        }
        if (show_progress) {
                printf(_("Copying "));
-               bscount = printf(_("%llu / %llu blocks (%llu%%)"),
-                                total_written,
-                                meta_blocks_count,
-                                (total_written + 50) / ((meta_blocks_count + 50) / 100));
+               bscount = print_progress(total_written, meta_blocks_count);
                fflush(stdout);
                last_update = time(NULL);
                start_time = time(NULL);
@@ -606,11 +613,8 @@ more_blocks:
                                 "interrupt again if you are sure\n"));
                        if (show_progress) {
                                printf(_("Copying "));
-                               bscount = printf(_("%llu / %llu blocks (%llu%%)"),
-                                                total_written,
-                                                meta_blocks_count,
-                                                (total_written + 50) / ((meta_blocks_count + 50)
-                                                                        / 100));
+                               bscount = print_progress(total_written,
+                                                        meta_blocks_count);
                                fflush(stdout);
                        }
 
@@ -621,23 +625,18 @@ more_blocks:
                        last_update = time(NULL);
                        while (bscount--)
                                printf("\b");
-                       bscount = printf(_("%llu / %llu blocks (%llu%%)"),
-                                        total_written,
-                                        meta_blocks_count,
-                                        (total_written + 50) /
-                                        ((meta_blocks_count + 50) / 100));
+                       bscount = print_progress(total_written,
+                                                meta_blocks_count);
                        duration = time(NULL) - start_time;
                        if (duration > 5) {
-                               time_t est = (duration *
-                                             meta_blocks_count / total_written) -
-                                       (duration);
+                               time_t est = (duration * meta_blocks_count /
+                                             total_written) - duration;
                                char buff[30];
                                strftime(buff, 30, "%T", gmtime(&est));
                                bscount += printf(_(" %s remaining at %.2f MB/s"),
-                                                 buff,
-                                                 ((float)total_written /
-                                                  ((1024 * 1024) / fs->blocksize)) /
-                                                 duration);
+                                                 buff, calc_rate(total_written,
+                                                                 fs->blocksize,
+                                                                 duration));
                        }
                        fflush (stdout);
                }
@@ -701,14 +700,9 @@ more_blocks:
                strftime(buff, 30, "%T", gmtime(&duration));
                printf(_("\b\b\b\b\b\b\b\bCopied %llu / %llu blocks (%llu%%) "
                         "in %s at %.2f MB/s       \n"),
-                      total_written,
-                      meta_blocks_count,
-                      (total_written + 50) / ((meta_blocks_count + 50) / 100),
-                      buff,
-                      ((float)total_written /
-                       ((1024 * 1024) / fs->blocksize)) /
-                      duration);
-
+                      total_written, meta_blocks_count,
+                      calc_percent(total_written, meta_blocks_count), buff,
+                      calc_rate(total_written, fs->blocksize, duration));
        }
 #ifdef HAVE_FTRUNCATE64
        if (sparse) {