1 files changed, 144 insertions, 0 deletions
diff --git a/util.c b/util.c
new file mode 100755
index 0000000..d1f6077
--- /dev/null
+++ b/util.c
@@ -0,0 +1,144 @@
+/* See LICENSE file for copyright and license details. */
+#include <errno.h>
+#include <stdarg.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "util.h"
+
+char *argv0;
+
+static void
+verr(const char *fmt, va_list ap)
+{
+	if (argv0 && strncmp(fmt, "usage", sizeof("usage") - 1))
+		fprintf(stderr, "%s: ", argv0);
+
+	vfprintf(stderr, fmt, ap);
+
+	if (fmt[0] && fmt[strlen(fmt) - 1] == ':') {
+		fputc(' ', stderr);
+		perror(NULL);
+	} else {
+		fputc('\n', stderr);
+	}
+}
+
+void
+warn(const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	verr(fmt, ap);
+	va_end(ap);
+}
+
+void
+die(const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	verr(fmt, ap);
+	va_end(ap);
+
+	exit(1);
+}
+
+static int
+evsnprintf(char *str, size_t size, const char *fmt, va_list ap)
+{
+	int ret;
+
+	ret = vsnprintf(str, size, fmt, ap);
+
+	if (ret < 0) {
+		warn("vsnprintf:");
+		return -1;
+	} else if ((size_t)ret >= size) {
+		warn("vsnprintf: Output truncated");
+		return -1;
+	}
+
+	return ret;
+}
+
+int
+esnprintf(char *str, size_t size, const char *fmt, ...)
+{
+	va_list ap;
+	int ret;
+
+	va_start(ap, fmt);
+	ret = evsnprintf(str, size, fmt, ap);
+	va_end(ap);
+
+	return ret;
+}
+
+const char *
+bprintf(const char *fmt, ...)
+{
+	va_list ap;
+	int ret;
+
+	va_start(ap, fmt);
+	ret = evsnprintf(buf, sizeof(buf), fmt, ap);
+	va_end(ap);
+
+	return (ret < 0) ? NULL : buf;
+}
+
+const char *
+fmt_human(uintmax_t num, int base)
+{
+	double scaled;
+	size_t i, prefixlen;
+	const char **prefix;
+	const char *prefix_1000[] = { "", "k", "M", "G", "T", "P", "E", "Z",
+	                              "Y" };
+	const char *prefix_1024[] = { "", "Ki", "Mi", "Gi", "Ti", "Pi", "Ei",
+	                              "Zi", "Yi" };
+
+	switch (base) {
+	case 1000:
+		prefix = prefix_1000;
+		prefixlen = LEN(prefix_1000);
+		break;
+	case 1024:
+		prefix = prefix_1024;
+		prefixlen = LEN(prefix_1024);
+		break;
+	default:
+		warn("fmt_human: Invalid base");
+		return NULL;
+	}
+
+	scaled = num;
+	for (i = 0; i < prefixlen && scaled >= base; i++)
+		scaled /= base;
+
+	return bprintf("%.1f %s", scaled, prefix[i]);
+}
+
+int
+pscanf(const char *path, const char *fmt, ...)
+{
+	FILE *fp;
+	va_list ap;
+	int n;
+
+	if (!(fp = fopen(path, "r"))) {
+		warn("fopen '%s':", path);
+		return -1;
+	}
+	va_start(ap, fmt);
+	n = vfscanf(fp, fmt, ap);
+	va_end(ap);
+	fclose(fp);
+
+	return (n == EOF) ? -1 : n;
+}