Use wchar_t strings for all of UI

vaswprintf is a nightmare.

1 files changed, 67 insertions, 0 deletions

diff --git a/pls.c b/pls.c
new file mode 100644
index 0000000..bd40dbd
--- /dev/null
+++ b/pls.c
@@ -0,0 +1,67 @@
+/* Copyright (C) 2018  Curtis McEnroe <june@causal.agency>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <wchar.h>
+
+wchar_t *wcssep(wchar_t **stringp, const wchar_t *delim) {
+	wchar_t *orig = *stringp;
+	if (!orig) return NULL;
+	size_t i = wcscspn(orig, delim);
+	*stringp = NULL;
+	if (orig[i]) {
+		orig[i] = '\0';
+		*stringp = &orig[i + 1];
+	}
+	return orig;
+}
+
+// From <https://en.cppreference.com/w/c/io/fwprintf#Notes>:
+//
+// While narrow strings provide snprintf, which makes it possible to determine
+// the required output buffer size, there is no equivalent for wide strings
+// (until C11's snwprintf_s), and in order to determine the buffer size, the
+// program may need to call swprintf, check the result value, and reallocate a
+// larger buffer, trying again until successful.
+//
+// snwprintf_s, unlike swprintf_s, will truncate the result to fit within the
+// array pointed to by buffer, even though truncation is treated as an error by
+// most bounds-checked functions.
+int vaswprintf(wchar_t **ret, const wchar_t *format, va_list ap) {
+	*ret = NULL;
+
+	for (size_t cap = 2 * wcslen(format);; cap *= 2) {
+		wchar_t *buf = realloc(*ret, 1 + cap);
+		if (!buf) goto fail;
+		*ret = buf;
+
+		va_list _ap;
+		va_copy(_ap, ap);
+		int len = vswprintf(*ret, 1 + cap, format, _ap);
+		va_end(_ap);
+
+		if (len >= 0) return len;
+		if (errno != EOVERFLOW) goto fail;
+	}
+
+fail:
+	free(*ret);
+	*ret = NULL;
+	return -1;
+}