/* * Copyright (C) 2007, 2008 Nokia Corporation * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 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 General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ /* * This file contains various common stuff. * * Authors: Artem Bityutskiy * Adrian Hunter */ #define PROGRAM_NAME "mtd-utils" #include <sys/time.h> #include <sys/types.h> #include <stdio.h> #include <string.h> #include <ctype.h> #include <stdlib.h> #include <unistd.h> #include "common.h" /** * get_multiplier - convert size specifier to an integer multiplier. * @str: the size specifier string * * This function parses the @str size specifier, which may be one of * 'KiB', 'MiB', or 'GiB' into an integer multiplier. Returns positive * size multiplier in case of success and %-1 in case of failure. */ static int get_multiplier(const char *str) { if (!str) return 1; /* Remove spaces before the specifier */ while (*str == ' ' || *str == '\t') str += 1; if (!strcmp(str, "KiB")) return 1024; if (!strcmp(str, "MiB")) return 1024 * 1024; if (!strcmp(str, "GiB")) return 1024 * 1024 * 1024; return -1; } /** * util_get_bytes - convert a string containing amount of bytes into an * integer * @str: string to convert * * This function parses @str which may have one of 'KiB', 'MiB', or 'GiB' * size specifiers. Returns positive amount of bytes in case of success and %-1 * in case of failure. */ long long util_get_bytes(const char *str) { char *endp; long long bytes = strtoull(str, &endp, 0); if (endp == str || bytes < 0) { fprintf(stderr, "incorrect amount of bytes: \"%s\"\n", str); return -1; } if (*endp != '\0') { int mult = get_multiplier(endp); if (mult == -1) { fprintf(stderr, "bad size specifier: \"%s\" - " "should be 'KiB', 'MiB' or 'GiB'\n", endp); return -1; } bytes *= mult; } return bytes; } /** * util_print_bytes - print bytes. * @bytes: variable to print * @bracket: whether brackets have to be put or not * * This is a helper function which prints amount of bytes in a human-readable * form, i.e., it prints the exact amount of bytes following by the approximate * amount of Kilobytes, Megabytes, or Gigabytes, depending on how big @bytes * is. */ void util_print_bytes(long long bytes, int bracket) { const char *p; int GiB = 1024 * 1024 * 1024; int MiB = 1024 * 1024; int KiB = 1024; if (bracket) p = " ("; else p = ", "; printf("%lld bytes", bytes); if (bytes > GiB) printf("%s%lld.%lld GiB", p, bytes / GiB, bytes % GiB / (GiB / 10)); else if (bytes > MiB) printf("%s%lld.%lld MiB", p, bytes / MiB, bytes % MiB / (MiB / 10)); else if (bytes > KiB && bytes != 0) printf("%s%lld.%lld KiB", p, bytes / KiB, bytes % KiB / (KiB / 10)); else return; if (bracket) printf(")"); } /** * util_srand - randomly seed the standard pseudo-random generator. * * This helper function seeds the standard libc pseudo-random generator with a * more or less random value to make sure the 'rand()' call does not return the * same sequence every time UBI utilities run. Returns zero in case of success * and a %-1 in case of error. */ int util_srand(void) { struct timeval tv; struct timezone tz; unsigned int seed; /* * Just assume that a combination of the PID + current time is a * reasonably random number. */ if (gettimeofday(&tv, &tz)) return -1; seed = (unsigned int)tv.tv_sec; seed += (unsigned int)tv.tv_usec; seed *= getpid(); seed %= RAND_MAX; srand(seed); return 0; }