strmap: add strmap_getn for non-terminated string search.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

diff --git a/ccan/strmap/strmap.c b/ccan/strmap/strmap.c
index 9fa51d0d40db4cf89fb16041585d71ea163b2238..16a30e036ad44c3492a9e05074747b7b15a6bff6 100644 (file)
--- a/ccan/strmap/strmap.c
+++ b/ccan/strmap/strmap.c
@@ -17,9 +17,8 @@ struct node {
 };
 
 /* Closest member to this in a non-empty map. */
-static struct strmap *closest(struct strmap *n, const char *member)
+static struct strmap *closest(struct strmap *n, const char *member, size_t len)
 {
-       size_t len = strlen(member);
        const u8 *bytes = (const u8 *)member;
 
        /* Anything with NULL value is a node. */
@@ -35,20 +34,26 @@ static struct strmap *closest(struct strmap *n, const char *member)
        return n;
 }
 
-void *strmap_get_(const struct strmap *map, const char *member)
+void *strmap_getn_(const struct strmap *map,
+                  const char *member, size_t memberlen)
 {
        struct strmap *n;
 
        /* Not empty map? */
        if (map->u.n) {
-               n = closest((struct strmap *)map, member);
-               if (streq(member, n->u.s))
+               n = closest((struct strmap *)map, member, memberlen);
+               if (!strncmp(member, n->u.s, memberlen) && !n->u.s[memberlen])
                        return n->v;
        }
        errno = ENOENT;
        return NULL;
 }
 
+void *strmap_get_(const struct strmap *map, const char *member)
+{
+       return strmap_getn_(map, member, strlen(member));
+}
+
 bool strmap_add_(struct strmap *map, const char *member, const void *value)
 {
        size_t len = strlen(member);
@@ -68,7 +73,7 @@ bool strmap_add_(struct strmap *map, const char *member, const void *value)
        }
 
        /* Find closest existing member. */
-       n = closest(map, member);
+       n = closest(map, member, len);
 
        /* Find where they differ. */
        for (byte_num = 0; n->u.s[byte_num] == member[byte_num]; byte_num++) {

diff --git a/ccan/strmap/strmap.h b/ccan/strmap/strmap.h
index 0b32e6befc0ca2974ad7304dd967e1c95fae75d3..8724c31dcbb20d2686cd33cbc39149209af7b767 100644 (file)
--- a/ccan/strmap/strmap.h
+++ b/ccan/strmap/strmap.h
@@ -72,7 +72,7 @@ static inline bool strmap_empty_(const struct strmap *map)
 /**
  * strmap_get - get a value from a string map
  * @map: the typed strmap to search.
- * @member: the string to search for.
+ * @member: the string to search for (nul terminated)
  *
  * Returns the value, or NULL if it isn't in the map (and sets errno = ENOENT).
  *
@@ -85,6 +85,23 @@ static inline bool strmap_empty_(const struct strmap *map)
        tcon_cast((map), canary, strmap_get_(tcon_unwrap(map), (member)))
 void *strmap_get_(const struct strmap *map, const char *member);
 
+/**
+ * strmap_getn - get a value from a string map
+ * @map: the typed strmap to search.
+ * @member: the string to search for.
+ * @memberlen: the length of @member.
+ *
+ * Returns the value, or NULL if it isn't in the map (and sets errno = ENOENT).
+ *
+ * Example:
+ *     val = strmap_getn(&map, "hello", 5);
+ *     if (val)
+ *             printf("hello => %i\n", *val);
+ */
+#define strmap_getn(map, member, n)                                    \
+       tcon_cast((map), canary, strmap_getn_(tcon_unwrap(map), (member), (n)))
+void *strmap_getn_(const struct strmap *map, const char *member, size_t n);
+
 /**
  * strmap_add - place a member in the string map.
  * @map: the typed strmap to add to.