exporter: fix remaining OOM (#12126)

plugins/exporter.koplugin/target/markdown.lua

@@ -125,10 +125,8 @@ function MarkdownExporter:export(t)
     local file = io.open(path, "w")
     if not file then return false end
     for idx, book in ipairs(t) do
-        file:write(md.prepareBookContent(book, self.settings.formatting_options, self.settings.highlight_formatting))
-        if idx < #t then
-            file:write("\n")
-        end
+        local tbl = md.prepareBookContent(book, self.settings.formatting_options, self.settings.highlight_formatting)
+        file:write(table.concat(tbl, "\n"))
     end
     file:write("\n\n_Generated at: " .. self:getTimeStamp() .. "_")
     file:close()
@@ -136,8 +134,9 @@ function MarkdownExporter:export(t)
 end
 
 function MarkdownExporter:share(t)
-    local content = md.prepareBookContent(t, self.settings.formatting_options, self.settings.highlight_formatting) .. "\n\n_Generated at: " .. self:getTimeStamp() .. "_"
-    self:shareText(content)
+    local tbl = md.prepareBookContent(t, self.settings.formatting_options, self.settings.highlight_formatting)
+    table.insert(tbl, "\n_Generated at: " .. self:getTimeStamp() .. "_")
+    self:shareText(table.concat(tbl, "\n"))
 end
 
 return MarkdownExporter

plugins/exporter.koplugin/target/text.lua

@@ -10,43 +10,45 @@ local TextExporter = require("base"):new {
 }
 
 local function format(booknotes)
+    local tbl = {}
+
+    -- Use wide_space to avoid crengine to treat it specially.
     local wide_space = "\227\128\128"
-    local content = ""
+
     if booknotes.title then
-        content = content .. wide_space .. booknotes.title .. "\n" .. wide_space .. "\n"
+        table.insert(tbl, wide_space .. booknotes.title)
+        table.insert(tbl, wide_space)
     end
     for ___, entry in ipairs(booknotes) do
         for ____, clipping in ipairs(entry) do
             if clipping.chapter then
-                content = content .. wide_space .. clipping.chapter .. "\n" .. wide_space .. "\n"
+                table.insert(tbl, wide_space .. clipping.chapter)
+                table.insert(tbl, wide_space)
             end
             local text = T(_("-- Page: %1, added on %2\n"), clipping.page, os.date("%c", clipping.time))
-            content = content .. wide_space .. wide_space .. text
+            table.insert(tbl, wide_space .. wide_space .. text)
             if clipping.text then
-                content = content .. clipping.text
+                table.insert(tbl, clipping.text)
             end
             if clipping.note then
-                content = content .. "\n---\n" .. clipping.note
+                table.insert(tbl, "\n---\n" .. clipping.note)
             end
             if clipping.image then
-                content = content .. _("<An image>")
+                table.insert(tbl, _("<An image>"))
             end
-            content = content .. "\n-=-=-=-=-=-\n"
+            table.insert(tbl, "-=-=-=-=-=-")
         end
     end
-    content = content .. "\n"
-    return content
+    return tbl
 end
 
 function TextExporter:export(t)
-    -- Use wide_space to avoid crengine to treat it specially.
-
     local path = self:getFilePath(t)
     local file = io.open(path, "a")
     if not file then return false end
     for __, booknotes in ipairs(t) do
-        local content = format(booknotes)
-        file:write(content)
+        local tbl = format(booknotes)
+        file:write(table.concat(tbl, "\n"))
     end
     file:close()
     return true

plugins/exporter.koplugin/template/md.lua

@@ -36,29 +36,28 @@ local formatters = {
 }
 
 local function prepareBookContent(book, formatting_options, highlight_formatting)
-    local content = ""
+    local tbl = {}
     local current_chapter = nil
-    content = content .. "# " .. book.title .. "\n"
+    table.insert(tbl, "# " .. book.title)
     local author = book.author or _("N/A")
-    content = content .. "##### " .. author:gsub("\n", ", ") .. "\n\n"
+    table.insert(tbl, "##### " .. author:gsub("\n", ", ") .. "\n")
     for _, note in ipairs(book) do
         local entry = note[1]
         if entry.chapter ~= current_chapter then
             current_chapter = entry.chapter
-            content = content .. "## " .. current_chapter .. "\n"
+            table.insert(tbl, "## " .. current_chapter)
         end
-        content = content .. "### Page " .. entry.page .. " @ " .. os.date("%d %B %Y %I:%M:%S %p", entry.time) .. "\n"
+        table.insert(tbl, "### Page " .. entry.page .. " @ " .. os.date("%d %B %Y %I:%M:%S %p", entry.time))
         if highlight_formatting then
-            content = content .. string.format(formatters[formatting_options[entry.drawer]].formatter, entry.text) .."\n"
+            table.insert(tbl, string.format(formatters[formatting_options[entry.drawer]].formatter, entry.text))
         else
-            content = content .. entry.text .. "\n"
+            table.insert(tbl, entry.text)
         end
         if entry.note then
-            content = content .. "\n---\n" .. entry.note .. "\n"
+            table.insert(tbl, "\n---\n" .. entry.note)
         end
-        content = content .. "\n"
     end
-    return content
+    return tbl
 end
 
 return {