slstatus/util.c
Aaron Marcher 381c2fa12a fmt_human: Improve types
size_t may not be enough, use 64 bit integers
2018-07-06 07:56:46 +02:00

146 lines
2.3 KiB
C

/* 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(uint64_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;
}