From e5e72e456dd1418b083e3feed94356231851f046 Mon Sep 17 00:00:00 2001
From: Mike Frysinger <vapier@gentoo.org>
Date: Sat, 18 Oct 2014 16:55:45 -0400
Subject: [PATCH] ddnuke: include percent and stop when we hit the disk limit

---
 ddnuke.c | 45 ++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 40 insertions(+), 5 deletions(-)

diff --git a/ddnuke.c b/ddnuke.c
index 3d01d36..774830e 100644
--- a/ddnuke.c
+++ b/ddnuke.c
@@ -3,11 +3,15 @@
  * written by Mike Frysinger <vapier>
  */
 
+#pragma GCC diagnostic warning "-Wall"
+#pragma GCC diagnostic warning "-Wextra"
+
 #define _FILE_OFFSET_BITS 64
 #define _LARGEFILE_SOURCE
 #define _LARGEFILE64_SOURCE
 #define _GNU_SOURCE
 
+#include <errno.h>
 #include <fcntl.h>
 #include <inttypes.h>
 #include <locale.h>
@@ -16,13 +20,16 @@
 #include <string.h>
 #include <time.h>
 #include <unistd.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <linux/fs.h>
 
 static const char zero[1024 * 1024];
 
 #define errp(msg, args...) \
 	do { \
-		printf("%s: " msg ": %m\n", argv[0], ## args); \
-		return 1; \
+		printf("%s: " msg ": %m\n", program_invocation_short_name, ## args); \
+		exit(1); \
 	} while (0)
 
 static unsigned long long mbps(struct timespec *stime, struct timespec *etime, off_t len)
@@ -35,6 +42,30 @@ static unsigned long long mbps(struct timespec *stime, struct timespec *etime, o
 	return 1000 * len / dtime;
 }
 
+static off_t get_blk_size(int fd)
+{
+	uint64_t size;
+	if (ioctl(fd, BLKGETSIZE64, &size))
+		errp("ioctl(BLKGETSIZE64) failed");
+	return size;
+}
+
+static off_t get_size(int fd)
+{
+	struct stat st;
+
+	if (fstat(fd, &st))
+		errp("could not stat %i", fd);
+
+	if (S_ISREG(st.st_mode))
+		return st.st_size;
+	else if (S_ISBLK(st.st_mode))
+		return get_blk_size(fd);
+
+	errno = EINVAL;
+	errp("unknown type of file");
+}
+
 int main(int argc, char *argv[])
 {
 	off_t offset = 0;
@@ -57,6 +88,8 @@ int main(int argc, char *argv[])
 	if (fd == -1)
 		errp("open(%s) failed", file);
 
+	off_t max_size = get_size(fd);
+
 	if (lseek(fd, offset, SEEK_SET) != offset)
 		errp("lseek(%"PRIu64"u) failed", offset);
 
@@ -65,10 +98,10 @@ int main(int argc, char *argv[])
 	clock_gettime(CLOCK_MONOTONIC, &stime);
 	itime = stime;
 
-	off_t pos = 0, last_pos = 0;
+	off_t pos = offset, last_pos = 0;
 	ssize_t ret;
 	int fsync_pos = 0;
-	while (1) {
+	while (pos < max_size) {
 		ret = write(fd, zero, sizeof(zero));
 		pos += ret;
 		if (ret != sizeof(zero)) {
@@ -77,7 +110,8 @@ int main(int argc, char *argv[])
 			return 0;
 		}
 
-		printf("%'llu bytes (%'llu MB/s)%20s\r", (unsigned long long)pos, speed, "");
+		printf("%'llu bytes %u%% (%'llu MB/s)%20s\r", (unsigned long long)pos,
+			(unsigned)((pos * 100) / max_size), speed, "");
 
 		if ((++fsync_pos % 16) == 0) {
 			speed = mbps(&stime, &etime, pos - last_pos);
@@ -87,5 +121,6 @@ int main(int argc, char *argv[])
 		}
 	}
 
+	printf("\n");
 	return 0;
 }
-- 
2.39.5