luci-base: Make default for FileUpload 'safe'

Some files and pointers to files are not safe to remove without a replacement
file and config pointing to the file.  For instance for uhttpd application in
the works, removing the certificate or key config or files without having the
replacements in places renders the WeUI inaccessible.

The only other place where FileUpload is currently used is for wifi certificates
for which the 'safe' handling is also preferred.  Therefore make the default for
the FileUpload widget the safe handling and add a property self.unsafeupload that
allows for the old unsafe handling should it prove useful in some case.

Also allow to specify a file already on router instead of uploading a file.

Signed-off By: Daniel Dickinson <openwrt@daniel.thecshore.com>

modules/luci-base/luasrc/cbi.lua

@@ -1811,6 +1811,7 @@ function Button.__init__(self, ...)
 	self.template  = "cbi/button"
 	self.inputstyle = nil
 	self.rmempty = true
+        self.unsafeupload = false
 end
 
 
@@ -1827,9 +1828,15 @@ function FileUpload.__init__(self, ...)
 end
 
 function FileUpload.formcreated(self, section)
+	if self.unsafeupload then
 		return AbstractValue.formcreated(self, section) or
 			self.map:formvalue("cbi.rlf."..section.."."..self.option) or
-		self.map:formvalue("cbi.rlf."..section.."."..self.option..".x")
+			self.map:formvalue("cbi.rlf."..section.."."..self.option..".x") or
+			self.map:formvalue("cbid."..self.map.config.."."..section.."."..self.option..".textbox")
+	else
+		return AbstractValue.formcreated(self, section) or
+			self.map:formvalue("cbid."..self.map.config.."."..section.."."..self.option..".textbox")
+	end
 end
 
 function FileUpload.cfgvalue(self, section)
@@ -1840,9 +1847,16 @@ function FileUpload.cfgvalue(self, section)
 	return nil
 end
 
+-- If we have a new value, use it
+-- otherwise use old value
+-- deletion should be managed by a separate button object
+-- unless self.unsafeupload is set in which case if the user
+-- choose to remove the old file we do so.
+-- Also, allow to specify (via textbox) a file already on router
 function FileUpload.formvalue(self, section)
 	local val = AbstractValue.formvalue(self, section)
 	if val then
+		if self.unsafeupload then
 			if not self.map:formvalue("cbi.rlf."..section.."."..self.option) and
 		   	    not self.map:formvalue("cbi.rlf."..section.."."..self.option..".x")
 			then
@@ -1850,16 +1864,32 @@ function FileUpload.formvalue(self, section)
 			end
 			fs.unlink(val)
 			self.value = nil
-	end
 			return nil
+                elseif val ~= "" then
+			return val
+                end
+	end
+	val = luci.http.formvalue("cbid."..self.map.config.."."..section.."."..self.option..".textbox")
+	if val == "" then
+		val = nil
+	end
+        if not self.unsafeupload then
+		if not val then
+			val = self.map:formvalue("cbi.rlf."..section.."."..self.option)
+		end
+        end
+	return val
 end
 
 function FileUpload.remove(self, section)
+	if self.unsafeupload then
 		local val = AbstractValue.formvalue(self, section)
 		if val and fs.access(val) then fs.unlink(val) end
 		return AbstractValue.remove(self, section)
+	else
+		return nil
+	end
 end
-
 
 FileBrowser = class(AbstractValue)
 

modules/luci-base/luasrc/view/cbi/upload.htm

@@ -6,9 +6,19 @@
 <%+cbi/valueheader%>
 	<% if s then %>
 		<%:Uploaded File%> (<%=t.byte_format(s.size)%>)
+                <% if self.unsafeupload then %>
 		    <input type="hidden"<%= attr("value", v) .. attr("name", cbid) .. attr("id", cbid) %> />
 		    <input class="cbi-button cbi-input-image" type="image" value="<%:Replace entry%>" name="cbi.rlf.<%=section .. "." .. self.option%>" alt="<%:Replace entry%>" title="<%:Replace entry%>" src="<%=resource%>/cbi/reload.gif" />
-	<% else %>
+                <% end %>
+	<% end %>
+
+        <% if not self.unsafeupload then %>
+		<input type="hidden"<%= attr("value", v) .. attr("name", "cbi.rlf." .. section .. "." .. self.option) .. attr("id", "cbi.rlf." .. section .. "." .. self.option) %> />
+	<% end %>
+		
+	<% if (not s) or (s and not self.unsafeupload) then %>
 		<input class="cbi-input-file" type="file"<%= attr("name", cbid) .. attr("id", cbid) %> />
 	<% end %>
+	<input type="text" class="cbi-input-text" onchange="cbi_d_update(this.id)"<%=
+		attr("name", cbid .. ".textbox") .. attr("id", cbid .. ".textbox") .. attr("value", luci.cbi.AbstractValue.cfgvalue(self, section) or self.default) .. ifattr(self.size, "size") .. ifattr(self.placeholder, "placeholder") .. ifattr(self.readonly, "readonly") .. ifattr(self.maxlength, "maxlength") %> />
 <%+cbi/valuefooter%>