[db,tool] add bisection initialization routines

2 files changed, 99 insertions, 10 deletions

diff --git a/src/luaotfload-database.lua b/src/luaotfload-database.lua
index 17cb4fd..3cccc17 100644
--- a/src/luaotfload-database.lua
+++ b/src/luaotfload-database.lua
@@ -2922,7 +2922,9 @@ end
 
 --- dbobj -> dbobj -> int -> int -> string * bool list
 local collect_font_filenames = function ()
-    ---
+
+    report ("info", 4, "db", "Scanning the filesystem for font files.")
+
     local filenames = { }
     tableappend (filenames, collect_font_filenames_texmf  ())
     tableappend (filenames, collect_font_filenames_system ())
@@ -2932,6 +2934,23 @@ local collect_font_filenames = function ()
     return filenames
 end
 
+--[[doc
+
+    count_font_files -- Return the number of files found by
+    collect_font_filenames. This function is exported primarily
+    for use with luaotfload-tool.lua in bisect mode.
+
+--doc]]--
+
+--- unit -> int
+local count_font_files = function ()
+    report ("info", 4, "db", "Counting font files.")
+    if not p_blacklist then
+        read_blacklist ()
+    end
+    return #collect_font_filenames ()
+end
+
 --- dbobj -> stats
 
 local collect_statistics = function (mappings)
@@ -3459,6 +3478,7 @@ names.read_blacklist              = read_blacklist
 names.sanitize_fontname           = sanitize_fontname
 names.getfilename                 = resolve_fullpath
 names.set_location_precedence     = set_location_precedence
+names.count_font_files            = count_font_files
 
 --- font cache
 names.purge_cache    = purge_cache
diff --git a/src/luaotfload-tool.lua b/src/luaotfload-tool.lua
index 03e7db3..5c7cb1d 100755
--- a/src/luaotfload-tool.lua
+++ b/src/luaotfload-tool.lua
@@ -48,6 +48,7 @@ kpse.set_program_name "luatex"
 local ioopen          = io.open
 local iowrite         = io.write
 local kpsefind_file   = kpse.find_file
+local mathfloor       = math.floor
 local next            = next
 local osdate          = os.date
 local ostype          = os.type
@@ -113,8 +114,11 @@ config.lualibs.prefer_merged    = true
 config.lualibs.load_extended    = true
 
 require "lualibs"
-local tabletohash               = table.tohash
+local iosavedata                = io.savedata
+local lfsisfile                 = lfs.isfile
 local stringsplit               = string.split
+local tableserialize            = table.serialize
+local tabletohash               = table.tohash
 
 --[[doc--
 \fileent{luatex-basics-gen.lua} calls functions from the
@@ -256,7 +260,7 @@ local help_msg = function (version)
                          names_gzip,
                          names_bin,
                          caches.getwritablepath (
-                         luaotfloadconfig.cache_dir)))
+                            luaotfloadconfig.cache_dir)))
 end
 
 local about = [[
@@ -288,7 +292,7 @@ local head_adornchars = {
 }
 
 local textwidth         = 80
-local wd_leftcolumn     = math.floor(textwidth * .25)
+local wd_leftcolumn     = mathfloor(textwidth * .25)
 local key_fmt           = stringformat([[%%%ds]], wd_leftcolumn)
 local val_fmt           = [[%s]]
 local fieldseparator    = ":"
@@ -771,13 +775,56 @@ actions.generate = function (job)
     return false, false
 end
 
+-------------------------------------------------------------------------------
+--- bisect mode
+-------------------------------------------------------------------------------
+
+local bisect_status_path = caches.getwritablepath "bisect"
+local bisect_status_file = bisect_status_path .."/" .. "luaotfload-bisect-status.lua"
+local bisect_status_fmt  = [[
+--[==[-------------------------------------------------------------------------
+    This file is generated by Luaotfload. It can be safely deleted.
+    Creation date: %s.
+-------------------------------------------------------------------------]==]--
+
+%s
+
+--- vim:ft=lua:ts=8:et:sw=2
+]]
+
+local write_bisect_status = function (data)
+    local payload = tableserialize (data, true)
+    local status  = stringformat (bisect_status_fmt,
+                                  osdate ("%Y-%m-d %H:%M:%S", os.time ()),
+                                  payload)
+    if status and iosavedata (bisect_status_file, status) then
+        report ("info", 4, "bisect",
+                "Bisection state written to %s.", bisect_status_file)
+        return true
+    end
+    report ("info", 0, "bisect",
+            "Failed to write bisection state to %s.", bisect_status_file)
+    return false
+end
+
 --[[doc--
 
     bisect_start -- Begin a bisect session. Determines the number of
     fonts and sets the initial high, low, and pivot values.
+
 --doc]]--
 
 local bisect_start = function ()
+    report ("info", 2, "bisect",
+            "Starting bisection of font database %q.", bisect_status_file)
+    local n     = names.count_font_files ()
+    local pivot = mathfloor (n / 2)
+    local data  = { { 1, n, pivot } }
+    report ("info", 0, "bisect", "Initializing pivot to %d.", pivot)
+    if write_bisect_status (data) then
+        return true
+    end
+    return false
 end
 
 --[[doc--
@@ -806,6 +853,25 @@ end
 --doc]]--
 
 local bisect_status = function ()
+    report ("info", 4, "bisect", "Testing for status file: %q.", bisect_status_file)
+    if not lfsisfile (bisect_status_file) then
+        report ("info", 2, "bisect", "No such file: %q.", bisect_status_file)
+        report ("info", 0, "bisect", "Not in bisect mode.")
+        return true
+    end
+    report ("info", 4, "bisect", "Reading status file: %q.", bisect_status_file)
+    local status = pcall (dofile, bisect_status_file)
+    if not status then
+        report ("info", 0, "bisect", "Could not read status file.")
+        return false
+    end
+    report ("info", 0, "bisect", "Bisecting through %d font files.", #status)
+    for i = #status, 1, -1 do
+        local step = status[i]
+        report ("info", 0, "bisect", "Step %d: lo=%d, hi=%d, pivot=%d.",
+                i, unpack (step))
+    end
+    return true
 end
 
 local bisect_modes = {
@@ -820,10 +886,13 @@ actions.bisect = function (job)
     local mode   = job.bisect
     local runner = bisect_modes[mode]
     if not runner then
-        report ("info", 0, "cache", "Unknown bisect directive %q.", mode)
+        report ("info", 0, "bisect", "Unknown directive %q.", mode)
         return false, false
     end
-    return true, false
+    if runner (job) then
+        return true, false
+    end
+    return false, false
 end
 
 actions.flush = function (job)
@@ -1270,7 +1339,7 @@ local process_cmdline = function ( ) -- unit -> jobspec
             end
         elseif v == "bisect" then
             result.bisect          = optarg[n]
-            actions_pending.bisect = true
+            action_pending.bisect = true
         end
     end
 
@@ -1299,16 +1368,16 @@ local main = function ( ) -- unit -> int
 
             if not success then
                 report (false, 0, "util",
-                        "Could not finish task", "%s", actionname)
+                        "Failed to execute task.", "%s", actionname)
                 retval = -1
                 exit   = true
             elseif not continue then
                 report (false, 3, "util",
-                        "Task completed, exiting", "%s", actionname)
+                        "Task completed, exiting.", "%s", actionname)
                 exit = true
             else
                 report (false, 3, "util",
-                        "Task completed successfully", "%s", actionname)
+                        "Task completed successfully.", "%s", actionname)
             end
         end
         if exit then break end