Split "comma separated values" parsing from mntent.h plumbing.

1 files changed, 99 insertions, 0 deletions

diff --git a/lib/commas.c b/lib/commas.c
new file mode 100644
index 00000000..03b2e345
--- /dev/null
+++ b/lib/commas.c
@@ -0,0 +1,99 @@
+/* commas.c - Deal with comma separated lists
+ *
+ * Copyright 2018 Rob Landley <rob@landley.net>
+ */
+
+#include "toys.h"
+
+// Traverse arg_list of csv, calling callback on each value
+void comma_args(struct arg_list *al, void *data, char *err,
+  char *(*callback)(void *data, char *str, int len))
+{
+  char *next, *arg;
+  int len;
+
+  if (CFG_TOYBOX_DEBUG && !err) err = "INTERNAL";
+
+  while (al) {
+    arg = al->arg;
+    while ((next = comma_iterate(&arg, &len)))
+      if ((next = callback(data, next, len)))
+        error_exit("%s '%s'\n%*c", err, al->arg,
+          (int)(5+strlen(toys.which->name)+strlen(err)+next-al->arg), '^');
+    al = al->next;
+  }
+}
+
+// Realloc *old with oldstring,newstring
+
+void comma_collate(char **old, char *new)
+{
+  char *temp, *atold = *old;
+
+  // Only add a comma if old string didn't end with one
+  if (atold && *atold) {
+    char *comma = ",";
+
+    if (atold[strlen(atold)-1] == ',') comma = "";
+    temp = xmprintf("%s%s%s", atold, comma, new);
+  } else temp = xstrdup(new);
+  free (atold);
+  *old = temp;
+}
+
+// iterate through strings in a comma separated list.
+// returns start of next entry or NULL if none
+// sets *len to length of entry (not including comma)
+// advances *list to start of next entry
+char *comma_iterate(char **list, int *len)
+{
+  char *start = *list, *end;
+
+  if (!*list || !**list) return 0;
+
+  if (!(end = strchr(*list, ','))) {
+    *len = strlen(*list);
+    *list = 0;
+  } else *list += (*len = end-start)+1;
+
+  return start;
+}
+
+// check all instances of opt and "no"opt in optlist, return true if opt
+// found and last instance wasn't no. If clean, remove each instance from list.
+int comma_scan(char *optlist, char *opt, int clean)
+{
+  int optlen = strlen(opt), len, no, got = 0;
+
+  if (optlist) for (;;) {
+    char *s = comma_iterate(&optlist, &len);
+
+    if (!s) break;
+    no = 2*(*s == 'n' && s[1] == 'o');
+    if (optlen == len-no && !strncmp(opt, s+no, optlen)) {
+      got = !no;
+      if (clean) {
+        if (optlist) memmove(s, optlist, strlen(optlist)+1);
+        else *s = 0;
+      }
+    }
+  }
+
+  return got;
+}
+
+// return true if all scanlist options enabled in optlist
+int comma_scanall(char *optlist, char *scanlist)
+{
+  int i = 1;
+
+  while (scanlist && *scanlist) {
+    char *opt = comma_iterate(&scanlist, &i), *s = xstrndup(opt, i);
+
+    i = comma_scan(optlist, s, 0);
+    free(s);
+    if (!i) break;
+  }
+
+  return i;
+}