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-rw-r--r--lualibs-io.lua186
1 files changed, 186 insertions, 0 deletions
diff --git a/lualibs-io.lua b/lualibs-io.lua
new file mode 100644
index 0000000..5a126da
--- /dev/null
+++ b/lualibs-io.lua
@@ -0,0 +1,186 @@
+if not modules then modules = { } end modules ['l-io'] = {
+ version = 1.001,
+ comment = "companion to luat-lib.mkiv",
+ author = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+ copyright = "PRAGMA ADE / ConTeXt Development Team",
+ license = "see context related readme files"
+}
+
+local byte, find, gsub = string.byte, string.find, string.gsub
+
+if string.find(os.getenv("PATH"),";") then
+ io.fileseparator, io.pathseparator = "\\", ";"
+else
+ io.fileseparator, io.pathseparator = "/" , ":"
+end
+
+function io.loaddata(filename,textmode)
+ 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
+ end
+end
+
+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 ""))
+ elseif type(data) == "function" then
+ data(f)
+ else
+ f:write(data or "")
+ end
+ f:close()
+ return true
+ else
+ return false
+ end
+end
+
+function io.exists(filename)
+ local f = io.open(filename)
+ if f == nil then
+ return false
+ else
+ assert(f:close())
+ return true
+ end
+end
+
+function io.size(filename)
+ local f = io.open(filename)
+ if f == nil then
+ return 0
+ else
+ local s = f:seek("end")
+ assert(f:close())
+ return s
+ end
+end
+
+function io.noflines(f)
+ local n = 0
+ for _ in f:lines() do
+ n = n + 1
+ end
+ f:seek('set',0)
+ return n
+end
+
+local nextchar = {
+ [ 4] = function(f)
+ return f:read(1,1,1,1)
+ end,
+ [ 2] = function(f)
+ return f:read(1,1)
+ end,
+ [ 1] = function(f)
+ return f:read(1)
+ end,
+ [-2] = function(f)
+ local a, b = f:read(1,1)
+ return b, a
+ end,
+ [-4] = function(f)
+ local a, b, c, d = f:read(1,1,1,1)
+ return d, c, b, a
+ end
+}
+
+function io.characters(f,n)
+ if f then
+ return nextchar[n or 1], f
+ else
+ return nil, nil
+ end
+end
+
+local nextbyte = {
+ [4] = function(f)
+ 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,
+ [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,
+ [-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
+}
+
+function io.bytes(f,n)
+ if f then
+ return nextbyte[n or 1], f
+ else
+ return nil, nil
+ end
+end
+
+function io.ask(question,default,options)
+ while true do
+ io.write(question)
+ if options then
+ io.write(string.format(" [%s]",table.concat(options,"|")))
+ end
+ if default then
+ io.write(string.format(" [%s]",default))
+ end
+ io.write(string.format(" "))
+ local answer = io.read()
+ answer = gsub(answer,"^%s*(.*)%s*$","%1")
+ if answer == "" and default then
+ return default
+ elseif not options then
+ return answer
+ else
+ for _,v in pairs(options) do
+ if v == answer then
+ return answer
+ end
+ end
+ local pattern = "^" .. answer
+ for _,v in pairs(options) do
+ if find(v,pattern) then
+ return v
+ end
+ end
+ end
+ end
+end