From b968f8ed826b9cc662c1a484040c55b0e0ad18c4 Mon Sep 17 00:00:00 2001
From: Mattias Andrée <maandree@kth.se>
Date: Sun, 22 Sep 2024 00:17:14 +0200
Subject: Expose device information in confirmation prompt
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Signed-off-by: Mattias Andrée <maandree@kth.se>
---
 ask.c | 158 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 156 insertions(+), 2 deletions(-)

(limited to 'ask.c')

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
 	}
-- 
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