+/*
+ * Prune the index to only contain stuff starting with "prefix"
+ */
+static void prune_cache(void)
+{
+ int pos = cache_name_pos(prefix, prefix_len);
+ unsigned int first, last;
+
+ if (pos < 0)
+ pos = -pos-1;
+ active_cache += pos;
+ active_nr -= pos;
+ first = 0;
+ last = active_nr;
+ while (last > first) {
+ int next = (last + first) >> 1;
+ struct cache_entry *ce = active_cache[next];
+ if (!strncmp(ce->name, prefix, prefix_len)) {
+ first = next+1;
+ continue;
+ }
+ last = next;
+ }
+ active_nr = last;
+}
+
+static void verify_pathspec(void)
+{
+ const char **p, *n, *prev;
+ char *real_prefix;
+ unsigned long max;
+
+ prev = NULL;
+ max = PATH_MAX;
+ for (p = pathspec; (n = *p) != NULL; p++) {
+ int i, len = 0;
+ for (i = 0; i < max; i++) {
+ char c = n[i];
+ if (prev && prev[i] != c)
+ break;
+ if (!c || c == '*' || c == '?')
+ break;
+ if (c == '/')
+ len = i+1;
+ }
+ prev = n;
+ if (len < max) {
+ max = len;
+ if (!max)
+ break;
+ }
+ }
+
+ if (prefix_offset > max || memcmp(prev, prefix, prefix_offset))
+ die("git-ls-files: cannot generate relative filenames containing '..'");
+
+ real_prefix = NULL;
+ prefix_len = max;
+ if (max) {
+ real_prefix = xmalloc(max + 1);
+ memcpy(real_prefix, prev, max);
+ real_prefix[max] = 0;
+ }
+ prefix = real_prefix;
+}
+