favor inline helpers instead of magic numbers

Hopefully this improves readability somewhat.

1 files changed, 21 insertions, 12 deletions

diff --git a/ext/mwrap/mwrap.c b/ext/mwrap/mwrap.c
index 22906bf..36eef05 100644
--- a/ext/mwrap/mwrap.c
+++ b/ext/mwrap/mwrap.c
@@ -154,11 +154,21 @@ struct src_loc {
         size_t total;
         struct cds_lfht_node hnode;
         uint32_t hval;
-        uint32_t kcapa;
+        uint32_t capa;
         char k[];
 };
 
-static inline int loc_eq(struct cds_lfht_node *node, const void *key)
+static int loc_is_addr(const struct src_loc *l)
+{
+        return l->capa == 0;
+}
+
+static size_t loc_size(const struct src_loc *l)
+{
+        return loc_is_addr(l) ? sizeof(uintptr_t) : l->capa;
+}
+
+static int loc_eq(struct cds_lfht_node *node, const void *key)
 {
         const struct src_loc *existing;
         const struct src_loc *k = key;
@@ -166,9 +176,8 @@ static inline int loc_eq(struct cds_lfht_node *node, const void *key)
         existing = caa_container_of(node, struct src_loc, hnode);
 
         return (k->hval == existing->hval &&
-                k->kcapa == existing->kcapa &&
-                memcmp(k->k, existing->k, k->kcapa == UINT32_MAX ?
-                       sizeof(uintptr_t) : k->kcapa) == 0);
+                k->capa == existing->capa &&
+                memcmp(k->k, existing->k, loc_size(k)) == 0);
 }
 
 static void totals_add(struct src_loc *k)
@@ -190,7 +199,7 @@ again:
                 uatomic_add(&l->total, k->total);
                 uatomic_add(&l->calls, 1);
         } else {
-                size_t n = k->kcapa == UINT32_MAX ? sizeof(uintptr_t) : k->kcapa;
+                size_t n = loc_size(k);
                 l = malloc(sizeof(*l) + n);
                 if (!l) goto out_unlock;
 
@@ -232,8 +241,8 @@ static void update_stats(size_t size, uintptr_t caller)
                 dst = int2str(line, dst, &int_size);
                 if (dst) {
                         *dst = 0;        /* terminate string */
-                        k->kcapa = (uint32_t)(dst - k->k + 1);
-                        k->hval = jhash(k->k, k->kcapa, 0xdeadbeef);
+                        k->capa = (uint32_t)(dst - k->k + 1);
+                        k->hval = jhash(k->k, k->capa, 0xdeadbeef);
                         totals_add(k);
                 } else {
                         rb_bug("bad math making key from location %s:%d\n",
@@ -244,7 +253,7 @@ unknown:
                 k = alloca(sizeof(*k) + xlen);
                 k->total = size;
                 memcpy(k->k, &caller, xlen);
-                k->kcapa = UINT32_MAX;
+                k->capa = 0;
                 k->hval = jhash(k->k, xlen, 0xdeadbeef);
                 totals_add(k);
         }
@@ -297,7 +306,7 @@ static void dump_to_file(struct dump_arg *a)
                         char **s = 0;
                         if (l->total <= a->min) continue;
 
-                        if (l->kcapa == UINT32_MAX) {
+                        if (loc_is_addr(l)) {
                                 s = backtrace_symbols(p, 1);
                                 p = s[0];
                         }
@@ -399,13 +408,13 @@ static VALUE dump_each_rcu(VALUE x)
                         VALUE v[3];
                         if (l->total <= a->min) continue;
 
-                        if (l->kcapa == UINT32_MAX) {
+                        if (loc_is_addr(l)) {
                                 char **s = backtrace_symbols((void *)l->k, 1);
                                 v[1] = rb_str_new_cstr(s[0]);
                                 free(s);
                         }
                         else {
-                                v[1] = rb_str_new(l->k, l->kcapa - 1);
+                                v[1] = rb_str_new(l->k, l->capa - 1);
                         }
                         v[0] = rb_funcall(v[1], id_uminus, 0);