Spacing & bracing updates per second edition of TAPL

Author: benhoyt

awkmake.awk

@@ -1,41 +1,52 @@
 BEGIN {
-    while (getline <"makefile" > 0)
+    while (getline <"makefile" > 0) {
         if ($0 ~ /^[A-Za-z]/) {  #  $1: $2 $3 ...
             sub(/:/, "")
             if (++names[nm = $1] > 1)
                 error(nm " is multiply defined")
             for (i = 2; i <= NF; i++) # remember targets
                 slist[nm, ++scnt[nm]] = $i
-        } else if ($0 ~ /^\t/)        # remember cmd for
+        } else if ($0 ~ /^\t/) {      # remember cmd for
             cmd[nm] = cmd[nm] $0 "\n" #   current name
-        else if (NF > 0)
+        } else if (NF > 0) {
             error("illegal line in makefile: " $0)
+        }
+    }
+
     ages()      # compute initial ages
+
     if (ARGV[1] in names) {
         if (update(ARGV[1]) == 0)
             print ARGV[1] " is up to date"
-    } else
+    } else {
         error(ARGV[1] " is not in makefile")
+    }
 }
 
 function ages(      f,n,t) {
     for (t = 1; ("ls -t" | getline f) > 0; t++)
-        age[f] = t   # all existing files get an age
+        age[f] = t         # all existing files get an age
     close("ls -t")
+
     for (n in names)
         if (!(n in age))   # if n has not been created
             age[n] = 9999  # make n really old
 }
+
 function update(n,   changed,i,s) {
-    if (!(n in age)) error(n " does not exist")
-    if (!(n in names)) return 0
+    if (!(n in age))
+        error(n " does not exist")
+    if (!(n in names))
+        return 0
     changed = 0
     visited[n] = 1
     for (i = 1; i <= scnt[n]; i++) {
-        if (visited[s = slist[n, i]] == 0) update(s)
+        if (visited[s = slist[n, i]] == 0)
+            update(s)
         else if (visited[s] == 1)
             error(s " and " n " are circularly defined")
-        if (age[s] <= age[n]) changed++
+        if (age[s] <= age[n])
+            changed++
     }
     visited[n] = 2
     if (changed || scnt[n] == 0) {
@@ -47,4 +58,5 @@ function update(n,   changed,i,s) {
     }
     return 0
 }
+
 function error(s) { print "error: " s; exit }