Improvements on the database and on the script

 * the info on a font now contains the checksum (might be needed for
   font caching)
 * very small optimizations in force mode
 * database version bumping
 * a new purge option (not taken into consideration yet)
 * new mechanism to remove old entries in the database without
   rebuilding everything, activated all the time but (for performance
reasons) will be activated only with the purge options in the very near
future.

1 files changed, 41 insertions, 29 deletions

diff --git a/otfl-font-nms.lua b/otfl-font-nms.lua
index 15466a1..305acdc 100644
--- a/otfl-font-nms.lua
+++ b/otfl-font-nms.lua
@@ -92,50 +92,65 @@ function fontloader.fullinfo(...)
     return t
 end
 
-local function load_font(filename, fontnames, texmf, status)
-    local database  = fontnames
-    local mappings  = database.mappings  or { }
-    local families  = database.families  or { }
-    local checksums = database.checksums or { }
+local function load_font(filename, fontnames, status, newfontnames, newstatus, texmf)
+    local mappings  = newfontnames.mappings  or { }
+    local families  = newfontnames.families  or { }
+    local oldmappings  = fontnames.mappings  or { }
+    local oldfamilies  = fontnames.families  or { }
     if filename then
-        local db_lastmodif = status[filename]
+        local db_lastmodif = status[filename] and status[filename].timestamp
         local true_lastmodif = lfs.attributes(filename, "modification")
+        newstatus[filename] = {timestamp = true_lastmodif, mappings = {}}
         if db_lastmodif and db_lastmodif == true_lastmodif then
-            if trace_loading then
-                logs.report("font already indexed: %s", filename)
+            for _, i in ipairs(status[filename].mappings) do
+                mappings[#mappings+1] = oldmappings[i]
+                table.insert(newstatus[filename].mappings, #mappings)
+                if oldmappings[i].names.family then
+                    if not families[oldmappings[i].names.family] then
+                        families[oldmappings[i].names.family] = {}
+                    end
+                    table.insert(families[oldmappings[i].names.family], #mappings)
+                elseif trace_loading then
+                    logs.report("font with broken names table: %s, ignored", filename)
+                end
+                if trace_loading then
+                    logs.report("font already indexed: %s", filename)
+                end
             end
-            return fontnames
+            return
         end
         if trace_loading then
             logs.report("loading font: %s", filename)
         end
-        status[filename] = true_lastmodif
+        local checksum = file.checksum(filename)
         local info = fontloader.info(filename)
         if info then
             if type(info) == "table" and #info > 1 then
                 for index,_ in ipairs(info) do
                     local fullinfo = fontloader.fullinfo(filename, index-1)
+                    fullinfo.checksum = checksum
                     if texmf then
                         fullinfo.filename = basename(filename)
                     end
                     mappings[#mappings+1] = fullinfo
+                    table.insert(newstatus[filename].mappings, #mappings)
                     if fullinfo.names.family then
                         if not families[fullinfo.names.family] then
                             families[fullinfo.names.family] = { }
                         end
                         table.insert(families[fullinfo.names.family], #mappings)
-                    else
-                        if trace_loading then
-                            logs.report("font with broken names table: %s, ignored", filename)
-                        end
+                    elseif trace_loading then
+                        logs.report("font with broken names table: %s, ignored", filename)
                     end
                 end
             else
                 local fullinfo = fontloader.fullinfo(filename)
+                fullinfo.checksum = checksum
                 if texmf then
                     fullinfo.filename = basename(filename)
                 end
                 mappings[#mappings+1] = fullinfo
+                table.insert(newstatus[filename].mappings, #mappings)
                 if fullinfo.names.family then
                     if not families[fullinfo.names.family] then
                         families[fullinfo.names.family] = { }
@@ -153,7 +168,6 @@ local function load_font(filename, fontnames, texmf, status)
             end
         end
     end
-    return database
 end
 
 -- We need to detect the OS (especially cygwin) to convert paths.
@@ -198,7 +212,7 @@ fonts.path_normalize = path_normalize
 --       in this script)
 -- - texmf is a boolean saying if we are scanning a texmf directory (always
 --       true in this script)
-local function scan_dir(dirname, fontnames, recursive, texmf, status)
+local function scan_dir(dirname, fontnames, status, newfontnames, newstatus, recursive, texmf)
     local list, found = { }, { }
     local nbfound = 0
     for _,ext in ipairs { "otf", "ttf", "ttc", "dfont" } do
@@ -226,14 +240,13 @@ local function scan_dir(dirname, fontnames, recursive, texmf, status)
     end
     for _,fnt in ipairs(list) do
         fnt = path_normalize(fnt)
-        fontnames = load_font(fnt, fontnames, texmf, status)
+        load_font(fnt, fontnames, status, newfontnames, newstatus, texmf)
     end
-    return fontnames
 end
 
 -- The function that scans all fonts in the texmf tree, through kpathsea
 -- variables OPENTYPEFONTS and TTFONTS of texmf.cnf
-local function scan_texmf_tree(fontnames, status)
+local function scan_texmf_tree(fontnames, status, newfontnames, newstatus)
     if trace_progress then
         if expandpath("$OSFONTDIR"):is_empty() then
             logs.report("scanning TEXMF fonts:")
@@ -253,12 +266,11 @@ local function scan_texmf_tree(fontnames, status)
             if not explored_dirs[d] then
                 count = count + 1
                 progress(count, #fontdirs)
-                fontnames = scan_dir(d, fontnames, false, true, status)
+                scan_dir(d, fontnames, status, newfontnames, newstatus, false, true)
                 explored_dirs[d] = true
             end
         end
     end
-    return fontnames
 end
 
 -- this function takes raw data returned by fc-list, parses it, normalizes the
@@ -279,7 +291,7 @@ end
 -- only if OSFONTDIR is empty (which is the case under most Unix by default).
 -- If OSFONTDIR is non-empty, this means that the system fonts it contains have
 -- already been scanned, and thus we don't scan them again.
-local function scan_os_fonts(fontnames, status)
+local function scan_os_fonts(fontnames, status, newfontnames, newstatus)
     if expandpath("$OSFONTDIR"):is_empty() then 
         if trace_progress then
             logs.report("scanning OS fonts:")
@@ -297,17 +309,15 @@ local function scan_os_fonts(fontnames, status)
         for _,fnt in ipairs(list) do
             count = count + 1
             progress(count, #list)
-            fontnames = load_font(fnt, fontnames, false, status)
+            load_font(fnt, fontnames, status, newfontnames, newstatus, false)
         end
     end
-    return fontnames
 end
 
 local function fontnames_init()
     return {
         mappings  = { },
         families  = { },
-        checksums = { },
         version   = names.version,
     }
 end
@@ -322,7 +332,7 @@ end
 -- - fontnames is the final table to return
 -- - force is whether we rebuild it from scratch or not
 -- - status is a table containing the current status of the database 
-local function update(fontnames, force, status)
+local function update(fontnames, status, force, purge)
     if force then
         fontnames = fontnames_init()
         status = status_init()
@@ -336,9 +346,11 @@ local function update(fontnames, force, status)
             end
         end
     end
-    fontnames = scan_texmf_tree(fontnames, status)
-    fontnames = scan_os_fonts  (fontnames, status)
-    return fontnames, status
+    local newfontnames = fontnames_init()
+    local newstatus    = status_init()
+    scan_texmf_tree(fontnames, status, newfontnames, newstatus)
+    scan_os_fonts  (fontnames, status, newfontnames, newstatus)
+    return newfontnames, newstatus
 end
 
 names.scan   = scan_dir