Make indirect_find() more resilient to embedded nuls

[perl/modules/indirect.git] / indirect.xs

diff --git a/indirect.xs b/indirect.xs
index 8ff064bc0796a52d89683502c6467986542bedb1..e1961194bf1585b083f947d0201ceaca4bfed003 100644 (file)
--- a/indirect.xs
+++ b/indirect.xs
@@ -494,44 +494,51 @@ STATIC STRLEN indirect_nextline(const char *s, STRLEN len) {
  return i;
 }
 
-STATIC int indirect_find(pTHX_ SV *sv, const char *s, STRLEN *pos) {
-#define indirect_find(N, S, P) indirect_find(aTHX_ (N), (S), (P))
- STRLEN len;
- const char *p, *r, *t, *u;
-
- r = SvPV_const(sv, len);
- if (len >= 1 && *r == '$') {
-  ++r;
-  --len;
-  s = strchr(s, '$');
-  if (!s)
+STATIC int indirect_find(pTHX_ SV *name_sv, const char *line_bufptr, STRLEN *name_pos) {
+#define indirect_find(NSV, LBP, NP) indirect_find(aTHX_ (NSV), (LBP), (NP))
+ STRLEN      name_len, line_len;
+ const char *name, *name_end;
+ const char *line, *line_end;
+ const char *p, *t, *u;
+
+ line     = SvPV_const(PL_linestr, line_len);
+ line_end = line + line_len;
+
+ name = SvPV_const(name_sv, name_len);
+ if (name_len >= 1 && *name == '$') {
+  ++name;
+  --name_len;
+  while (line_bufptr < line_end && *line_bufptr != '$')
+   ++line_bufptr;
+  if (line_bufptr >= line_end)
    return 0;
  }
+ name_end = name + name_len;
 
- p = s;
+ p = line_bufptr;
  while (1) {
-  p = strstr(p, r);
+  p = ninstr(p, line_end, name, name_end);
   if (!p)
    return 0;
-  if (!isALNUM(p[len]))
+  if (!isALNUM(p[name_len]))
    break;
-  /* p points to a word that has r as prefix, skip the rest of the word */
-  p += len + 1;
+  /* p points to a word that has name as prefix, skip the rest of the word */
+  p += name_len + 1;
   while (isALNUM(*p))
    ++p;
  }
 
- t = SvPV_const(PL_linestr, len);
+ t = line;
  u = t;
  while (t <= p) {
-  STRLEN i = indirect_nextline(t, len);
-  if (i >= len)
+  STRLEN i = indirect_nextline(t, line_len);
+  if (i >= line_len)
    break;
-  u    = t;
-  t   += i;
-  len -= i;
+  u         = t;
+  t        += i;
+  line_len -= i;
  }
- *pos = p - u;
+ *name_pos = p - u;
 
  return 1;
 }