From 18ce6e98590635d9127dbe32464988d524f2a6ea Mon Sep 17 00:00:00 2001
From: "Steffen (Daode) Nurpmeso" <steffen@sdaoden.eu>
Date: Fri, 16 Sep 2016 13:57:52 +0200
Subject: [PATCH] n_string_resize(): change semantics

---
 nailfuns.h |  7 ++++---
 strings.c  | 12 ++++++------
 2 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/nailfuns.h b/nailfuns.h
index f56c26cf..46e14c27 100644
--- a/nailfuns.h
+++ b/nailfuns.h
@@ -2033,7 +2033,7 @@ FL struct str * n_str_add_buf(struct str *self, char const *buf, uiz_t buflen
 
 /* Truncate to size, which must be LE current length */
 #define n_string_trunc(S,L) \
-   (assert(UICMP(z, L, <=, (S)->s_len)),  (S)->s_len = (ui32_t)(L), (S))
+   (assert(UICMP(z, L, <=, (S)->s_len)), (S)->s_len = (ui32_t)(L), (S))
 
 /* Release buffer ownership */
 #define n_string_drop_ownership(S) \
@@ -2049,10 +2049,11 @@ FL struct n_string *n_string_clear(struct n_string *self SMALLOC_DEBUG_ARGS);
 # define n_string_clear(S)       ((S)->s_size != 0 ? (n_string_clear)(S) : (S))
 #endif
 
-/* Reserve room for noof additional bytes.  The latter also adjusts the length
- * accordingly, but the (possible) additional storage isn't initialized */
+/* Reserve room for noof additional bytes, but don't adjust length (yet) */
 FL struct n_string *n_string_reserve(struct n_string *self, size_t noof
                      SMALLOC_DEBUG_ARGS);
+
+/* Resize to exactly nlen bytes; any new storage isn't initialized */
 FL struct n_string *n_string_resize(struct n_string *self, size_t nlen
                      SMALLOC_DEBUG_ARGS);
 
diff --git a/strings.c b/strings.c
index 603de0a9..84c48ce3 100644
--- a/strings.c
+++ b/strings.c
@@ -647,17 +647,17 @@ FL struct n_string *
 
 FL struct n_string *
 (n_string_resize)(struct n_string *self, size_t nlen SMALLOC_DEBUG_ARGS){
-   ui32_t l;
    NYD_ENTER;
 
    assert(self != NULL);
+#if 0 /* FIXME memory alloc too large */
+   if(SI32_MAX - n_ALIGN(1) - l <= noof)
+      n_panic(_("Memory allocation too large"));
+#endif
 
-   if((l = self->s_len) > nlen)
-      self->s_len = nlen;
-   else{
-      nlen -= l;
+   if(self->s_len < nlen)
       self = (n_string_reserve)(self, nlen SMALLOC_DEBUG_ARGSCALL);
-   }
+   self->s_len = (ui32_t)nlen;
    NYD_LEAVE;
    return self;
 }
-- 
2.11.4.GIT