libmutt: fix regex code for degenerate cases

diff --git a/mutt/regex.c b/mutt/regex.c
index cd6fb26c76bdb348a56899aed214f85abc028eb3..2be1a93775a80f121e915cb010dc09741c6f5566 100644 (file)
--- a/mutt/regex.c
+++ b/mutt/regex.c
@@ -51,6 +51,8 @@
  */
 struct Regex *mutt_regex_compile(const char *str, int flags)
 {
+  if (!str || !*str)
+    return NULL;
   struct Regex *rx = mutt_mem_calloc(1, sizeof(struct Regex));
   rx->pattern = mutt_str_strdup(str);
   rx->regex = mutt_mem_calloc(1, sizeof(regex_t));
@@ -70,7 +72,7 @@ struct Regex *mutt_regex_compile(const char *str, int flags)
  */
 struct Regex *mutt_regex_new(const char *str, int flags, struct Buffer *err)
 {
-  if (!str)
+  if (!str || !*str)
     return NULL;
 
   int rflags = 0;
@@ -128,7 +130,7 @@ void mutt_regex_free(struct Regex **r)
  */
 int mutt_regexlist_add(struct RegexList *rl, const char *str, int flags, struct Buffer *err)
 {
-  if (!str || !*str)
+  if (!rl || !str || !*str)
     return 0;
 
   struct Regex *rx = mutt_regex_compile(str, flags);
@@ -187,9 +189,9 @@ void mutt_regexlist_free(struct RegexList *rl)
  */
 bool mutt_regexlist_match(struct RegexList *rl, const char *str)
 {
-  struct RegexListNode *np = NULL;
-  if (!str)
+  if (!rl || !str)
     return false;
+  struct RegexListNode *np = NULL;
   STAILQ_FOREACH(np, rl, entries)
   {
     if (!np->regex || !np->regex->regex)
@@ -261,13 +263,14 @@ int mutt_regexlist_remove(struct RegexList *rl, const char *str)
 int mutt_replacelist_add(struct ReplaceList *rl, const char *pat,
                          const char *templ, struct Buffer *err)
 {
-  if (!pat || !*pat || !templ)
+  if (!rl || !pat || !*pat || !templ)
     return 0;
 
   struct Regex *rx = mutt_regex_compile(pat, REG_ICASE);
   if (!rx)
   {
-    mutt_buffer_printf(err, _("Bad regex: %s"), pat);
+    if (err)
+      mutt_buffer_printf(err, _("Bad regex: %s"), pat);
     return -1;
   }
 
@@ -322,7 +325,8 @@ int mutt_replacelist_add(struct ReplaceList *rl, const char *pat,
 
   if (np->nmatch > np->regex->regex->re_nsub)
   {
-    mutt_buffer_printf(err, "%s", _("Not enough subexpressions for template"));
+    if (err)
+      mutt_buffer_printf(err, "%s", _("Not enough subexpressions for template"));
     mutt_replacelist_remove(rl, pat);
     return -1;
   }
@@ -357,7 +361,7 @@ char *mutt_replacelist_apply(struct ReplaceList *rl, char *buf, size_t buflen, c
   if (buf && buflen)
     buf[0] = '\0';
 
-  if (!str || (*str == '\0') || (buf && !buflen))
+  if (!rl || !str || (*str == '\0') || (buf && !buflen))
     return buf;
 
   twinbuf[0][0] = '\0';