diff options
| -rw-r--r-- | lualibs-io.lua | 105 |
1 files changed, 77 insertions, 28 deletions
diff --git a/lualibs-io.lua b/lualibs-io.lua index 66e2793..a9269ab 100644 --- a/lualibs-io.lua +++ b/lualibs-io.lua @@ -6,7 +6,10 @@ if not modules then modules = { } end modules ['l-io'] = { license = "see context related readme files" } -local byte, find, gsub = string.byte, string.find, string.gsub +local io = io +local byte, find, gsub, format = string.byte, string.find, string.gsub, string.format +local concat = table.concat +local type = type if string.find(os.getenv("PATH"),";") then io.fileseparator, io.pathseparator = "\\", ";" @@ -14,16 +17,14 @@ else io.fileseparator, io.pathseparator = "/" , ":" end -function io.loaddata(filename,textmode) +function io.loaddata(filename,textmode) -- return nil if empty local f = io.open(filename,(textmode and 'r') or 'rb') if f then - -- collectgarbage("step") -- sometimes makes a big difference in mem consumption local data = f:read('*all') - -- garbagecollector.check(data) f:close() - return data - else - return nil + if #data > 0 then + return data + end end end @@ -31,19 +32,59 @@ function io.savedata(filename,data,joiner) local f = io.open(filename,"wb") if f then if type(data) == "table" then - f:write(table.join(data,joiner or "")) + f:write(concat(data,joiner or "")) elseif type(data) == "function" then data(f) else f:write(data or "") end f:close() + io.flush() return true else return false end end +function io.loadlines(filename,n) -- return nil if empty + local f = io.open(filename,'r') + if f then + if n then + local lines = { } + for i=1,n do + local line = f:read("*lines") + if line then + lines[#lines+1] = line + else + break + end + end + f:close() + lines = concat(lines,"\n") + if #lines > 0 then + return lines + end + else + local line = f:read("*line") or "" + assert(f:close()) + if #line > 0 then + return line + end + end + end +end + +function io.loadchunk(filename,n) + local f = io.open(filename,'rb') + if f then + local data = f:read(n or 1024) + f:close() + if #data > 0 then + return data + end + end +end + function io.exists(filename) local f = io.open(filename) if f == nil then @@ -66,12 +107,19 @@ function io.size(filename) end function io.noflines(f) - local n = 0 - for _ in f:lines() do - n = n + 1 + if type(f) == "string" then + local f = io.open(filename) + local n = f and io.noflines(f) or 0 + assert(f:close()) + return n + else + local n = 0 + for _ in f:lines() do + n = n + 1 + end + f:seek('set',0) + return n end - f:seek('set',0) - return n end local nextchar = { @@ -97,8 +145,6 @@ local nextchar = { function io.characters(f,n) if f then return nextchar[n or 1], f - else - return nil, nil end end @@ -107,40 +153,42 @@ local nextbyte = { local a, b, c, d = f:read(1,1,1,1) if d then return byte(a), byte(b), byte(c), byte(d) - else - return nil, nil, nil, nil + end + end, + [3] = function(f) + local a, b, c = f:read(1,1,1) + if b then + return byte(a), byte(b), byte(c) end end, [2] = function(f) local a, b = f:read(1,1) if b then return byte(a), byte(b) - else - return nil, nil end end, [1] = function (f) local a = f:read(1) if a then return byte(a) - else - return nil end end, [-2] = function (f) local a, b = f:read(1,1) if b then return byte(b), byte(a) - else - return nil, nil + end + end, + [-3] = function(f) + local a, b, c = f:read(1,1,1) + if b then + return byte(c), byte(b), byte(a) end end, [-4] = function(f) local a, b, c, d = f:read(1,1,1,1) if d then return byte(d), byte(c), byte(b), byte(a) - else - return nil, nil, nil, nil end end } @@ -157,12 +205,13 @@ function io.ask(question,default,options) while true do io.write(question) if options then - io.write(string.format(" [%s]",table.concat(options,"|"))) + io.write(format(" [%s]",concat(options,"|"))) end if default then - io.write(string.format(" [%s]",default)) + io.write(format(" [%s]",default)) end - io.write(string.format(" ")) + io.write(format(" ")) + io.flush() local answer = io.read() answer = gsub(answer,"^%s*(.*)%s*$","%1") if answer == "" and default then |