Explicitly check for file existance and read permission of --info input file

before handing it over to the desktop tools

2 files changed, 54 insertions, 3 deletions

diff --git a/portland/xdg-utils/scripts/xdg-mime.in b/portland/xdg-utils/scripts/xdg-mime.in
index 73298fe..5c9063a 100755
--- a/portland/xdg-utils/scripts/xdg-mime.in
+++ b/portland/xdg-utils/scripts/xdg-mime.in
@@ -350,6 +350,8 @@ if [ "$action" = "makedefault" ]; then
 fi
 
 if [ "$action" = "info" ]; then
+    check_input_file "$filename"
+
     detectDE
 
     if [ x"$DE" = x"" ]; then
diff --git a/portland/xdg-utils/scripts/xdg-utils-common.in b/portland/xdg-utils/scripts/xdg-utils-common.in
index 4204998..a8ab2dc 100644
--- a/portland/xdg-utils/scripts/xdg-utils-common.in
+++ b/portland/xdg-utils/scripts/xdg-utils-common.in
@@ -36,7 +36,7 @@ exit_failure_syntax()
         echo "Try '@NAME@ --help' for more information." >&2
     else
         usage
-        echo "Use 'man @NAME@' or '@NAME@ --manual' for additional info." 
+        echo "Use 'man @NAME@' or '@NAME@ --manual' for additional info."
     fi
 
     exit 1
@@ -78,6 +78,55 @@ exit_failure_operation_failed()
     exit 4
 }
 
+#------------------------------------------------------------
+# Exit script on insufficient permission to read a specified file
+
+exit_failure_file_permission_read()
+{
+    if [ $# -gt 0 ]; then
+        echo "@NAME@: $@" >&2
+    fi
+
+    exit 5
+}
+
+#------------------------------------------------------------
+# Exit script on insufficient permission to read a specified file
+
+exit_failure_file_permission_write()
+{
+    if [ $# -gt 0 ]; then
+        echo "@NAME@: $@" >&2
+    fi
+
+    exit 6
+}
+
+check_input_file()
+{
+    if [ ! -e "$1" ]; then
+        exit_failure_file_missing "file '$1' does not exist"
+    fi
+    if [ ! -r "$1" ]; then
+        exit_failure_file_permission_read "no permission to read file '$1'"
+    fi
+}
+
+check_output_file()
+{
+    # if the file exists, check if it is writeable
+    # if it does not exists, check if we are allowed to write on the directory
+    if [ -e "$1" ]; then
+        if [ ! -w "$1" ]; then
+            exit_failure_file_permission_write "no permission to write to file '$1'"
+        fi
+    else
+        DIR=`dirname "$1"`
+        if [ ! -w "$DIR" -o ! -x "$DIR" ]; then
+            exit_failure_file_permission_write "no permission to create file '$1'"
+        fi
+    fi
+}
 
 #----------------------------------------
 # Checks for shared commands, e.g. --help
@@ -91,7 +140,7 @@ check_common_commands()
         case "$parm" in
             --help)
             usage
-            echo "Use 'man @NAME@' or '@NAME@ --manual' for additional info." 
+            echo "Use 'man @NAME@' or '@NAME@ --manual' for additional info."
             exit_success
             ;;
 
@@ -111,7 +160,7 @@ check_common_commands()
 check_common_commands "$@"
 if [ ${XDG_UTILS_DEBUG_LEVEL-0} -lt 1 ]; then
     # Be silent
-    xdg_redirect_output=" > /dev/null 2> /dev/null" 
+    xdg_redirect_output=" > /dev/null 2> /dev/null"
 else
     # All output to stderr
     xdg_redirect_output=" >&2"