Simplify format specifiers for uintmax_t

[slstatus.git] / util.c

diff --git a/util.c b/util.c
index 6008ffc..eaa3001 100644 (file)
--- a/util.c
+++ b/util.c
@@ -1,25 +1,128 @@
 /* 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;
-       size_t len;
+       int ret;
 
        va_start(ap, fmt);
-       len = vsnprintf(buf, sizeof(buf) - 1, fmt, ap);
+       ret = evsnprintf(buf, sizeof(buf), fmt, ap);
        va_end(ap);
 
-       if (len >= sizeof(buf))
-               buf[sizeof(buf)-1] = '\0';
+       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 buf;
+       return bprintf("%.1f%s", scaled, prefix[i]);
 }
 
 int
@@ -30,7 +133,7 @@ pscanf(const char *path, const char *fmt, ...)
        int n;
 
        if (!(fp = fopen(path, "r"))) {
-               fprintf(stderr, "fopen '%s': %s\n", path, strerror(errno));
+               warn("fopen '%s':", path);
                return -1;
        }
        va_start(ap, fmt);