submodule: fix segmentation fault in submodule--helper clone

diff --git a/dir.c b/dir.c
index 8a9d8c061b3834ea4ff856adca1e7cc490d1954d..552af237040b3bab95d94f43b169a6278623cea3 100644 (file)
--- a/dir.c
+++ b/dir.c
@@ -930,6 +930,75 @@ static int match_sticky(struct exclude *exc, const char *pathname, int pathlen,
        return 0;
 }
 
+static inline int different_decisions(const struct exclude *a,
+                                     const struct exclude *b)
+{
+       return (a->flags & EXC_FLAG_NEGATIVE) != (b->flags & EXC_FLAG_NEGATIVE);
+}
+
+/*
+ * Return non-zero if pathname is a directory and an ancestor of the
+ * literal path in a pattern.
+ */
+static int match_directory_part(const char *pathname, int pathlen,
+                               int *dtype, struct exclude *x)
+{
+       const char      *base       = x->base;
+       int              baselen    = x->baselen ? x->baselen - 1 : 0;
+       const char      *pattern    = x->pattern;
+       int              prefix     = x->nowildcardlen;
+       int              patternlen = x->patternlen;
+
+       if (*dtype == DT_UNKNOWN)
+               *dtype = get_dtype(NULL, pathname, pathlen);
+       if (*dtype != DT_DIR)
+               return 0;
+
+       if (*pattern == '/') {
+               pattern++;
+               patternlen--;
+               prefix--;
+       }
+
+       if (baselen) {
+               if (((pathlen < baselen && base[pathlen] == '/') ||
+                    pathlen == baselen) &&
+                   !strncmp_icase(pathname, base, pathlen))
+                       return 1;
+               pathname += baselen + 1;
+               pathlen  -= baselen + 1;
+       }
+
+
+       if (prefix &&
+           (((pathlen < prefix && pattern[pathlen] == '/') ||
+             pathlen == prefix) &&
+            !strncmp_icase(pathname, pattern, pathlen)))
+               return 1;
+
+       return 0;
+}
+
+static struct exclude *should_descend(const char *pathname, int pathlen,
+                                     int *dtype, struct exclude_list *el,
+                                     struct exclude *exc)
+{
+       int i;
+
+       for (i = el->nr - 1; 0 <= i; i--) {
+               struct exclude *x = el->excludes[i];
+
+               if (x == exc)
+                       break;
+
+               if (!(x->flags & EXC_FLAG_NODIR) &&
+                   different_decisions(x, exc) &&
+                   match_directory_part(pathname, pathlen, dtype, x))
+                       return x;
+       }
+       return NULL;
+}
+
 /*
  * Scan the given exclude list in reverse to see whether pathname
  * should be ignored.  The first match (i.e. the last on the list), if
@@ -943,7 +1012,7 @@ static struct exclude *last_exclude_matching_from_list(const char *pathname,
                                                       struct exclude_list *el)
 {
        struct exclude *exc = NULL; /* undecided */
-       int i;
+       int i, maybe_descend = 0;
 
        if (!el->nr)
                return NULL;    /* undefined */
@@ -955,6 +1024,10 @@ static struct exclude *last_exclude_matching_from_list(const char *pathname,
                const char *exclude = x->pattern;
                int prefix = x->nowildcardlen;
 
+               if (!maybe_descend && i < el->nr - 1 &&
+                   different_decisions(x, el->excludes[i+1]))
+                       maybe_descend = 1;
+
                if (x->sticky_paths.nr) {
                        if (*dtype == DT_UNKNOWN)
                                *dtype = get_dtype(NULL, pathname, pathlen);
@@ -998,6 +1071,34 @@ static struct exclude *last_exclude_matching_from_list(const char *pathname,
                return NULL;
        }
 
+       /*
+        * We have found a matching pattern "exc" that may exclude whole
+        * directory. We also found that there may be a pattern that matches
+        * something inside the directory and reincludes stuff.
+        *
+        * Go through the patterns again, find that pattern and double check.
+        * If it's true, return "undecided" and keep descending in. "exc" is
+        * marked sticky so that it continues to match inside the directory.
+        */
+       if (!(exc->flags & EXC_FLAG_NEGATIVE) && maybe_descend) {
+               struct exclude *x;
+
+               if (*dtype == DT_UNKNOWN)
+                       *dtype = get_dtype(NULL, pathname, pathlen);
+
+               if (*dtype == DT_DIR &&
+                   (x = should_descend(pathname, pathlen, dtype, el, exc))) {
+                       add_sticky(exc, pathname, pathlen);
+                       trace_printf_key(&trace_exclude,
+                                        "exclude: %.*s vs %s at line %d => %s,"
+                                        " forced open by %s at line %d => n/a\n",
+                                        pathlen, pathname, exc->pattern, exc->srcpos,
+                                        exc->flags & EXC_FLAG_NEGATIVE ? "no" : "yes",
+                                        x->pattern, x->srcpos);
+                       return NULL;
+               }
+       }
+
        trace_printf_key(&trace_exclude, "exclude: %.*s vs %s at line %d => %s%s\n",
                         pathlen, pathname, exc->pattern, exc->srcpos,
                         exc->flags & EXC_FLAG_NEGATIVE ? "no" : "yes",
@@ -2096,6 +2197,12 @@ int read_directory(struct dir_struct *dir, const char *path, int len, const stru
        if (has_symlink_leading_path(path, len))
                return dir->nr;
 
+       /*
+        * Stay on the safe side. if read_directory() has run once on
+        * "dir", some sticky flag may have been left. Clear them all.
+        */
+       clear_sticky(dir);
+
        /*
         * exclude patterns are treated like positive ones in
         * create_simplify. Usually exclude patterns should be a