FIX processor topology length

src/modules/processor.lua

@@ -160,13 +160,14 @@ return function(update_freq, main_state, config, common, width, point)
       local hwp_paths = cpu.get_hwp_paths(topology)
       local freq_labels
       local cpu_group_map = cpu.topology_to_cpu_map(topology)
+      local ngroups = pure.length(topology)
       local format_label = function(group_id)
          return __string_format('Ave Freq (%i)', group_id)
       end
-      if #topology == 1 then
+      if ngroups == 1 then
          freq_labels = {'Ave Freq'}
       else
-         freq_labels = pure.map_n(format_label, #topology)
+         freq_labels = pure.map_n(format_label, ngroups)
       end
       local cpu_status = common.make_text_rows(
          point.x,
@@ -193,7 +194,7 @@ return function(update_freq, main_state, config, common, width, point)
       local dynamic = pure.partial(common.text_rows_draw_dynamic, cpu_status)
       return common.mk_acc(
          width,
-         text_spacing * #topology,
+         text_spacing * ngroups,
          update,
          static,
          dynamic

src/pure.lua

@@ -136,6 +136,14 @@ end
 --------------------------------------------------------------------------------
 -- random list things
 
+M.length = function(tbl)
+   local n = 0
+   for _, _ in pairs(tbl) do
+      n = n + 1
+   end
+   return n
+end
+
 -- a stupid but composable function
 M.get = function(key, tbl)
    return tbl[key]

src/sys.lua

@@ -172,12 +172,6 @@ end
 --------------------------------------------------------------------------------
 -- cpu
 
--- ASSUME lscpu will always be available
-
-M.get_core_number = function()
-   return __tonumber(i_o.read_file('/proc/cpuinfo', 'cpu cores%s+:%s(%d+)'))
-end
-
 M.get_cpu_number = function(topology)
    local n = 0
    for g, c in pairs(topology) do
@@ -195,6 +189,7 @@ end
 -- return a table with keys corresponding to physcial core id and values to
 -- the number of threads of each core (usually 1 or 2)
 M.get_core_threads = function()
+   i_o.assert_exe_exists('lscpu')
    local cmd = 'lscpu -y -p=core | grep -v \'^#\' | sort -k1,1n | uniq -c'
    local flip = function(c) return {__tonumber(c[2]), __tonumber(c[1])} end
    local make_indexer = pure.compose(
@@ -206,8 +201,8 @@ M.get_core_threads = function()
 end
 
 local get_coretemp_mapper = function()
-   local d = get_coretemp_dir()
    i_o.assert_exe_exists('grep')
+   local d = get_coretemp_dir()
    local get_labels = pure.compose(
       i_o.execute_cmd,
       pure.partial(__string_format, 'grep Core %s/temp*_label', true)
@@ -224,6 +219,9 @@ local get_coretemp_mapper = function()
 end
 
 M.get_core_topology = function()
+   i_o.assert_exe_exists('lscpu')
+   i_o.assert_exe_exists('grep')
+   i_o.assert_exe_exists('sort')
    local coretemp_paths = get_coretemp_mapper()
    local assign_cpu = function(i, x)
       return {
@@ -285,6 +283,7 @@ M.read_ave_freqs = function(topology, cpu_group_map)
    -- scaling_cur_freq in sysfs seems to do the same thing. It appears lscpu
    -- (which queries /proc/cpuinfo) is much faster and doesn't have this jittery
    -- problem.
+   i_o.assert_exe_exists('lscpu')
    local out = i_o.execute_cmd('lscpu -p=MHZ')
    local init_freqs = function(v)
       local r = {}