write conf scripts

src/io/conf.c

@@ -0,0 +1,35 @@
+#include "conf.h"
+
+#include <string.h>
+
+#include "../types.h"
+#include "../util/atrb.h"
+
+/* Matches s1 with s2, returns a pointer to s1 where the match stopped. */
+static const char *strmat(const char *s1, const char *s2) PURE NONNULL((1, 2));
+static const char *strmat(const char *s1, const char *s2)
+{
+	while ((*s1 == *s2) & !!*s1)
+		s1++, s2++;
+	return s1;
+}
+
+int conf_getkeyval(const char *restrict buf, const char *const restrict *restrict keys, int klen, const char *restrict *restrict out)
+{
+	const char *tmp = NULL;
+
+	ASSUME((klen > 0));
+	int i = 0;
+	for (; i < klen && !tmp; i++) {
+		tmp = strmat(buf, keys[i]);
+		tmp = keys[i][buf - tmp] ? tmp : 0;
+	}
+
+	if (!tmp || *tmp != '=')
+		return -1;
+
+	*out = tmp + 1;
+	return i;
+}
+
+int conf_val(int);

src/io/conf.h

@@ -0,0 +1,12 @@
+#pragma once
+#include "../types.h"
+#include "../util/atrb.h"
+
+/* Gets the key and value, if present. Writes the pointer for the value to `out`.
+ * Returns the key index, or <0 upon failure. */
+int conf_getkeyval(const char *restrict buf, const char *const restrict *restrict keys, int klen,
+	const char *restrict *restrict out) NONNULL((1, 2, 4));
+
+/* Processes the value of `type` in `val`. Outputs to `out`.
+ * Returns non-zero on failure. */
+int conf_procval(u8 type, const char *restrict val, void *restrict out) NONNULL((2, 3));