Expose device information in confirmation prompt

Signed-off-by: Mattias Andrée <maandree@kth.se>

4 files changed, 200 insertions, 4 deletions

diff --git a/ask.c b/ask.c
index bb8fa50..5917a12 100644
--- a/ask.c
+++ b/ask.c
@@ -5,6 +5,146 @@
 #endif
 
 
+struct devinfo {
+	char *part;
+	char *dev;
+	char *part_start;
+	char *part_size;
+	char *dev_size;
+	char *dev_wwid;
+	char *dev_model;
+	char *dev_serial;
+	char *dev_transport;
+};
+
+
+static void
+destroy_devinfo(struct devinfo *info)
+{
+	free(info->part);
+	free(info->dev);
+	free(info->part_start);
+	free(info->part_size);
+	free(info->dev_size);
+	free(info->dev_wwid);
+	free(info->dev_model);
+	free(info->dev_serial);
+	free(info->dev_transport);
+}
+
+
+static char *
+strip(char *s)
+{
+	char *ret = s;
+	if (s) {
+		char *p = s;
+		while (*s) {
+			while (*s && !isspace(*s))
+				s++;
+			p = s;
+			while (*s && isspace(*s))
+				s++;
+		}
+		*p = '\0';
+	}
+	return ret;
+}
+
+
+static char *
+fmtsize(char *s)
+{
+	uintmax_t val;
+	char *end, *ret;
+	char buf[256];
+
+	if (!s)
+		return NULL;
+
+	errno = 0;
+	val = strtoumax(s, &end, 10);
+	if (!isdigit(*s) || *end || errno || val > (uintmax_t)(OFF_MAX / 512)) {
+		free(s);
+		return NULL;
+	}
+
+	ret = estrdup(exact_and_human_size((off_t)val * 512, buf, 1));
+	free(s);
+	return ret;
+}
+
+
+static int
+get_devinfo(struct devinfo *info, const char *name)
+{
+	struct stat st;
+	char *path, *p;
+	int dfd;
+
+	info->part = NULL;
+	info->dev = NULL;
+	info->part_start = NULL;
+	info->part_size = NULL;
+	info->dev_size = NULL;
+	info->dev_wwid = NULL;
+	info->dev_model = NULL;
+	info->dev_serial = NULL;
+	info->dev_transport = NULL;
+
+	path = emalloc(sizeof("/sys/class/block/") + strlen(name));
+	p = stpcpy(stpcpy(path, "/sys/class/block/"), name);
+
+	dfd = open(path, O_PATH);
+	if (dfd < 0)
+		return 0;
+
+	info->part = strip(readtextfileat(dfd, "partition"));
+	if (info->part) {
+		info->part_start = fmtsize(strip(readtextfileat(dfd, "start")));
+		info->part_size = fmtsize(strip(readtextfileat(dfd, "size")));
+
+		close(dfd);
+
+		if (!isdigit(p[-1]))
+			return 1;
+		while (isdigit(p[-1]))
+			*--p = '\0';
+
+		dfd = open(path, O_PATH);
+		if (dfd < 0) {
+			if (isalpha(p[-1])) {
+				*--p = '\0';
+				dfd = open(path, O_PATH);
+			}
+			if (dfd < 0)
+				return 1;
+		}
+
+		if (fstatat(dfd, name, &st, 0) || !S_ISDIR(st.st_mode)) {
+			close(dfd);
+			return 1;
+		}
+
+		while (p[-1] != '/')
+			p--;
+		info->dev = estrdup(p);
+	}
+
+	info->dev_size = fmtsize(strip(readtextfileat(dfd, "size")));
+	info->dev_wwid = strip(readtextfileat(dfd, "wwid"));
+	if (!info->dev_wwid)
+		info->dev_wwid = strip(readtextfileat(dfd, "device/wwid"));
+	info->dev_model = strip(readtextfileat(dfd, "device/model"));
+	info->dev_serial = strip(readtextfileat(dfd, "device/serial"));
+	info->dev_transport = strip(readtextfileat(dfd, "device/transport"));
+
+	close(dfd);
+
+	return info->part || info->dev_size || info->dev_wwid || info->dev_model || info->dev_serial || info->dev_transport;
+}
+
+
 int
 confirm(const char *device, off_t off, off_t len, off_t end)
 {
@@ -66,8 +206,22 @@ confirm(const char *device, off_t off, off_t len, off_t end)
 #if defined(__linux__)
 	} else if (S_ISBLK(st.st_mode)) {
 		char *devname = get_device_name(major(st.st_rdev), minor(st.st_rdev));
-		if (devname) {
-			/* TODO display device identity and size (look in /sys/class/block/<devname>/) */
+		struct devinfo info;
+		if (devname && get_devinfo(&info, devname)) {
+			if ((dprintf(ttyfd, "\nFile is identified as block device %s. Details below:\n", devname) < 0) ||
+			    (info.part && info.dev && dprintf(ttyfd, "\tPartition %s of %s\n", info.part, info.dev) < 0) ||
+			    (info.part_size && dprintf(ttyfd, "\tSize of the partition: %s\n", info.part_size) < 0) ||
+			    (info.part_start && dprintf(ttyfd, "\tOffset of the partition: %s\n", info.part_start) < 0) ||
+			    (info.dev_size && dprintf(ttyfd, "\tSize of the device: %s\n", info.dev_size) < 0) ||
+			    (info.dev_model && dprintf(ttyfd, "\tModel of the device: %s\n", info.dev_model) < 0) ||
+			    (info.dev_serial && dprintf(ttyfd, "\tSerial number of the device: %s\n", info.dev_serial) < 0) ||
+			    (info.dev_transport && dprintf(ttyfd, "\tTransport type of the device: %s\n", info.dev_transport) < 0) ||
+			    (info.dev_wwid && dprintf(ttyfd, "\tWWID of the device: %s\n", info.dev_wwid) < 0))
+				goto printerror;
+			destroy_devinfo(&info);
+		} else if (devname) {
+			if (dprintf(ttyfd, "\nFile is identified as block device %s. No details available.\n", devname) < 0)
+				goto printerror;
 		}
 #endif
 	}
diff --git a/common.h b/common.h
index ad4b8a8..891f1c6 100644
--- a/common.h
+++ b/common.h
@@ -51,6 +51,7 @@ struct status {
 
 
 /* io.c */
+char *readtextfileat(int dfd, const char *path);
 void writeall(int fd, const void *data, size_t n, const char *fname);
 void filecpy(int fd, off_t src, off_t len, const char *fname);
 off_t filesize(int fd, const char *fname);
diff --git a/deadshred.c b/deadshred.c
index 8b8a74c..baa7bf6 100644
--- a/deadshred.c
+++ b/deadshred.c
@@ -57,8 +57,8 @@ print_status(int done, struct status *s)
 	libsimple_difftimespec(&time_spent, &s->now, &start_time);
 
 	sprintf(bufi == 0 ? buf1 : buf2,
-	        "%ji bytes (%s, %s, %.2lf %%) of %s (%s) shredded\033[K\n"
-	        "failed writes: %ju; bad sections: %ju (%ji bytes, %s, %s)\033[K\n"
+	        "%ji byte%s (%s, %s, %.2lf %%) of %s (%s) shredded\033[K\n"
+	        "failed writes: %ju; bad sections: %ju (%ji byte%s, %s, %s)\033[K\n"
 	        "time spent shredding: %s; performance: %s\033[K\n"
 	        "time since last successful write: %s\033[K\n"
 	        "maximum time until a successful write: %s\033[K\n"
@@ -66,6 +66,7 @@ print_status(int done, struct status *s)
 	        "%s",
 	        /* line 1 { */
 	        (intmax_t)s->shredded,
+	        s->shredded == 1 ? "" : "s",
 	        humansize1000(s->shredded, subbuf1),
 	        humansize1024(s->shredded, subbuf2),
 	        100 * (double)s->shredded / (double)total_size,
@@ -75,6 +76,7 @@ print_status(int done, struct status *s)
 	        s->bad_writes,
 	        s->bad_sections,
 	        (intmax_t)s->bad_bytes,
+	        s->bad_bytes == 1 ? "" : "s",
 	        humansize1000(s->bad_bytes, subbuf3),
 	        humansize1024(s->bad_bytes, subbuf4),
 	        /* } line 3 { */
diff --git a/io.c b/io.c
index 98afe53..063265b 100644
--- a/io.c
+++ b/io.c
@@ -2,6 +2,45 @@
 #include "common.h"
 
 
+char *
+readtextfileat(int dfd, const char *path)
+{
+	int fd;
+	char *text = NULL;
+	size_t size = 0;
+	size_t len = 0;
+	ssize_t r;
+
+	fd = openat(dfd, path, O_RDONLY);
+	if (fd < 0)
+		return NULL;
+
+	for (;;) {
+		if (len == size) {
+			size = size ? size * 2U : 64U;
+			text = erealloc(text, size);
+		}
+		r = read(fd, &text[len], size - len);
+		if (r <= 0) {
+			if (!r)
+				break;
+			if (errno == EINTR)
+				continue;
+			close(fd);
+			return NULL;
+		}
+		len += (size_t)r;
+	}
+
+	close(fd);
+
+	if (len == size)
+		text = erealloc(text, len + 1U);
+	text[len] = '\0';
+	return text;
+}
+
+
 void
 writeall(int fd, const void *data, size_t n, const char *fname)
 {