From f341a269c92720b20ecdda68971a33c124fba414 Mon Sep 17 00:00:00 2001
From: Ken Gaillot <kgaillot@redhat.com>
Date: Jun 10 2020 17:56:11 +0000
Subject: Refactor: libcrmcommon: add convenience macros for plurals


I've avoided making s_if_plural() an official API due to its hackiness, but
it really is the best solution for now. Promote it to pcmk__plural_s(), along
with a companion macro pcmk__plural_alt() for more complicated plurals.

---

diff --git a/include/crm/common/internal.h b/include/crm/common/internal.h
index 484c836..ee560c9 100644
--- a/include/crm/common/internal.h
+++ b/include/crm/common/internal.h
@@ -107,6 +107,29 @@ bool crm_compress_string(const char *data, int length, int max, char **result,
                          unsigned int *result_len);
 gint crm_alpha_sort(gconstpointer a, gconstpointer b);
 
+/* Correctly displaying singular or plural is complicated; consider "1 node has"
+ * vs. "2 nodes have". A flexible solution is to pluralize entire strings, e.g.
+ *
+ * if (a == 1) {
+ *     crm_info("singular message"):
+ * } else {
+ *     crm_info("plural message");
+ * }
+ *
+ * though even that's not sufficient for all languages besides English (if we
+ * ever desire to do translations of output and log messages). But the following
+ * convenience macros are "good enough" and more concise for many cases.
+ */
+
+/* Example:
+ * crm_info("Found %d %s", nentries,
+ *          pcmk__plural_alt(nentries, "entry", "entries"));
+ */
+#define pcmk__plural_alt(i, s1, s2) (((i) == 1)? (s1) : (s2))
+
+// Example: crm_info("Found %d node%s", nnodes, pcmk__plural_s(nnodes));
+#define pcmk__plural_s(i) pcmk__plural_alt(i, "", "s")
+
 static inline char *
 crm_concat(const char *prefix, const char *suffix, char join)
 {