From d8e35a4fed044b6722c1d46b9cbf394100e256f5 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Sat, 6 Oct 2012 13:08:54 +0300
Subject: [PATCH] More comprehensive check for mountable devices

---
 main.c | 90 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 89 insertions(+), 1 deletion(-)

diff --git a/main.c b/main.c
index 55cfe0f..6be8352 100644
--- a/main.c
+++ b/main.c
@@ -1,6 +1,8 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
 #include <dirent.h>
 #include <mntent.h>
 #include <sys/stat.h>
@@ -220,6 +222,92 @@ void free_mounted_devices(char **mounted)
 	free(mounted);
 }
 
+int is_removable(char *devpath)
+{
+	char fnbuf[256];
+	int len;
+	char *ptr;
+	int fd;
+
+	len = snprintf(fnbuf, sizeof(fnbuf), "/sys%s", devpath);
+	if(len+10>=(int)sizeof(fnbuf))
+		return 0;
+
+	for(ptr=fnbuf+len; (ptr>fnbuf && *ptr!='/'); --ptr) ;
+	strcpy(ptr, "/removable");
+	fd = open(fnbuf, O_RDONLY);
+	if(fd!=-1)
+	{
+		char c;
+		read(fd, &c, 1);
+		close(fd);
+		if(c=='1')
+		{
+			if(verbosity>=2)
+				printf("  Removable\n");
+			return 1;
+		}
+		if(verbosity>=2)
+			printf("  Not removable\n");
+	}
+
+	return 0;
+}
+
+int check_buses(char *devpath, char **buses)
+{
+	char fnbuf[256];
+	char *ptr;
+	int len;
+
+	len = snprintf(fnbuf, sizeof(fnbuf), "/sys%s", devpath);
+	if(len+10>=(int)sizeof(fnbuf))
+		return 0;
+
+	for(ptr=fnbuf+len; ptr>fnbuf+12; --ptr)
+		if(*ptr=='/')
+		{
+			char linkbuf[256];
+			strcpy(ptr, "/subsystem");
+			len = readlink(fnbuf, linkbuf, sizeof(linkbuf)-1);
+			*ptr = 0;
+
+			if(len!=-1)
+			{
+				int i;
+				linkbuf[len] = 0;
+				for(; (len>0 && linkbuf[len-1]!='/'); --len) ;
+				if(verbosity>=2)
+					printf("  Subsystem of %s is %s\n", fnbuf, linkbuf+len);
+				for(i=0; buses[i]; ++i)
+					if(strcmp(linkbuf+len, buses[i])==0)
+						return 1;
+			}
+		}
+
+	return 0;
+}
+
+int can_mount(Property *props)
+{
+	static char *removable_buses[] = { "usb", "firewire", 0 };
+	char *devpath;
+	int i;
+
+	if(!match_property_value(props, "DEVTYPE", "partition"))
+		return 0;
+
+	devpath = get_property_value(props, "DEVPATH");
+	if(is_removable(devpath))
+		return 1;
+
+	for(i=0; removable_buses[i]; ++i)
+		if(match_property_value(props, "ID_BUS", removable_buses[i]))
+			return 1;
+
+	return check_buses(devpath, removable_buses);
+}
+
 char **get_device_nodes(char *dirname)
 {
 	DIR *dir;
@@ -327,7 +415,7 @@ Device *get_devices(void)
 				printf("  %s = %s\n", props[j].name, props[j].value);
 		}
 
-		if(match_property_value(props, "ID_BUS", "usb") && match_property_value(props, "DEVTYPE", "partition"))
+		if(can_mount(props))
 		{
 			char *devname;
 			char *label;
-- 
2.45.2