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add libosmcore utilities
osmo_hexdump is particularly useful. previously it was only defined, but not implemented. this cause random behaviour upon call, often resulting in memory corruption. Change-Id: Ifd9120fa951f41693903fb657d10826959f1599f
This commit is contained in:
Kévin Redon
632
firmware/libosmocore/source/utils.c
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632
firmware/libosmocore/source/utils.c
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@@ -0,0 +1,632 @@
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/*
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* (C) 2011 by Harald Welte <laforge@gnumonks.org>
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* (C) 2011 by Sylvain Munaut <tnt@246tNt.com>
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* (C) 2014 by Nils O. Selåsdal <noselasd@fiane.dyndns.org>
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*
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* All Rights Reserved
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*
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* SPDX-License-Identifier: GPL-2.0+
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License along
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* with this program; if not, write to the Free Software Foundation, Inc.,
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* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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*/
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#include <stdbool.h>
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#include <string.h>
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#include <stdint.h>
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#include <errno.h>
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#include <stdio.h>
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#include <inttypes.h>
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#include <osmocom/core/utils.h>
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#include <osmocom/core/bit64gen.h>
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/*! \addtogroup utils
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* @{
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* various utility routines
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*
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* \file utils.c */
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static char namebuf[255];
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/*! get human-readable string for given value
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* \param[in] vs Array of value_string tuples
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* \param[in] val Value to be converted
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* \returns pointer to human-readable string
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*
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* If val is found in vs, the array's string entry is returned. Otherwise, an
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* "unknown" string containing the actual value is composed in a static buffer
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* that is reused across invocations.
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*/
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const char *get_value_string(const struct value_string *vs, uint32_t val)
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{
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const char *str = get_value_string_or_null(vs, val);
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if (str)
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return str;
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snprintf(namebuf, sizeof(namebuf), "unknown 0x%"PRIx32, val);
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namebuf[sizeof(namebuf) - 1] = '\0';
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return namebuf;
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}
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/*! get human-readable string or NULL for given value
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* \param[in] vs Array of value_string tuples
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* \param[in] val Value to be converted
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* \returns pointer to human-readable string or NULL if val is not found
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*/
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const char *get_value_string_or_null(const struct value_string *vs,
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uint32_t val)
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{
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int i;
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for (i = 0;; i++) {
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if (vs[i].value == 0 && vs[i].str == NULL)
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break;
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if (vs[i].value == val)
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return vs[i].str;
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}
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return NULL;
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}
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/*! get numeric value for given human-readable string
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* \param[in] vs Array of value_string tuples
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* \param[in] str human-readable string
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* \returns numeric value (>0) or negative numer in case of error
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*/
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int get_string_value(const struct value_string *vs, const char *str)
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{
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int i;
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for (i = 0;; i++) {
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if (vs[i].value == 0 && vs[i].str == NULL)
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break;
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if (!strcasecmp(vs[i].str, str))
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return vs[i].value;
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}
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return -EINVAL;
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}
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/*! Convert BCD-encoded digit into printable character
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* \param[in] bcd A single BCD-encoded digit
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* \returns single printable character
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*/
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char osmo_bcd2char(uint8_t bcd)
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{
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if (bcd < 0xa)
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return '0' + bcd;
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else
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return 'A' + (bcd - 0xa);
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}
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/*! Convert number in ASCII to BCD value
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* \param[in] c ASCII character
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* \returns BCD encoded value of character
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*/
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uint8_t osmo_char2bcd(char c)
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{
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if (c >= '0' && c <= '9')
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return c - 0x30;
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else if (c >= 'A' && c <= 'F')
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return 0xa + (c - 'A');
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else if (c >= 'a' && c <= 'f')
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return 0xa + (c - 'a');
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else
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return 0;
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}
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/*! Parse a string containing hexadecimal digits
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* \param[in] str string containing ASCII encoded hexadecimal digits
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* \param[out] b output buffer
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* \param[in] max_len maximum space in output buffer
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* \returns number of parsed octets, or -1 on error
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*/
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int osmo_hexparse(const char *str, uint8_t *b, int max_len)
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{
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char c;
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uint8_t v;
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const char *strpos;
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unsigned int nibblepos = 0;
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memset(b, 0x00, max_len);
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for (strpos = str; (c = *strpos); strpos++) {
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/* skip whitespace */
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if (c == ' ' || c == '\t' || c == '\n' || c == '\r')
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continue;
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/* If the buffer is too small, error out */
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if (nibblepos >= (max_len << 1))
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return -1;
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if (c >= '0' && c <= '9')
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v = c - '0';
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else if (c >= 'a' && c <= 'f')
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v = 10 + (c - 'a');
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else if (c >= 'A' && c <= 'F')
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v = 10 + (c - 'A');
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else
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return -1;
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b[nibblepos >> 1] |= v << (nibblepos & 1 ? 0 : 4);
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nibblepos ++;
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}
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/* In case of uneven amount of digits, the last byte is not complete
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* and that's an error. */
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if (nibblepos & 1)
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return -1;
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return nibblepos >> 1;
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}
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static char hexd_buff[4096];
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static const char hex_chars[] = "0123456789abcdef";
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static char *_osmo_hexdump(const unsigned char *buf, int len, const char *delim)
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{
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int i;
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char *cur = hexd_buff;
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hexd_buff[0] = 0;
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for (i = 0; i < len; i++) {
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const char *delimp = delim;
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int len_remain = sizeof(hexd_buff) - (cur - hexd_buff);
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if (len_remain < 3)
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break;
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*cur++ = hex_chars[buf[i] >> 4];
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*cur++ = hex_chars[buf[i] & 0xf];
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while (len_remain > 1 && *delimp) {
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*cur++ = *delimp++;
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len_remain--;
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}
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*cur = 0;
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}
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hexd_buff[sizeof(hexd_buff)-1] = 0;
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return hexd_buff;
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}
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/*! Convert a sequence of unpacked bits to ASCII string
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* \param[in] bits A sequence of unpacked bits
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* \param[in] len Length of bits
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*/
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char *osmo_ubit_dump(const uint8_t *bits, unsigned int len)
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{
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int i;
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if (len > sizeof(hexd_buff)-1)
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len = sizeof(hexd_buff)-1;
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memset(hexd_buff, 0, sizeof(hexd_buff));
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for (i = 0; i < len; i++) {
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char outch;
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switch (bits[i]) {
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case 0:
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outch = '0';
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break;
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case 0xff:
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outch = '?';
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break;
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case 1:
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outch = '1';
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break;
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default:
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outch = 'E';
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break;
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}
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hexd_buff[i] = outch;
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}
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hexd_buff[sizeof(hexd_buff)-1] = 0;
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return hexd_buff;
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}
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/*! Convert binary sequence to hexadecimal ASCII string
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* \param[in] buf pointer to sequence of bytes
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* \param[in] len length of buf in number of bytes
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* \returns pointer to zero-terminated string
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*
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* This function will print a sequence of bytes as hexadecimal numbers,
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* adding one space character between each byte (e.g. "1a ef d9")
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*
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* The maximum size of the output buffer is 4096 bytes, i.e. the maximum
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* number of input bytes that can be printed in one call is 1365!
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*/
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char *osmo_hexdump(const unsigned char *buf, int len)
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{
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return _osmo_hexdump(buf, len, " ");
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}
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/*! Convert binary sequence to hexadecimal ASCII string
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* \param[in] buf pointer to sequence of bytes
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* \param[in] len length of buf in number of bytes
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* \returns pointer to zero-terminated string
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*
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* This function will print a sequence of bytes as hexadecimal numbers,
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* without any space character between each byte (e.g. "1aefd9")
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*
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* The maximum size of the output buffer is 4096 bytes, i.e. the maximum
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* number of input bytes that can be printed in one call is 2048!
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*/
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char *osmo_hexdump_nospc(const unsigned char *buf, int len)
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{
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return _osmo_hexdump(buf, len, "");
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}
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/* Compat with previous typo to preserve abi */
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char *osmo_osmo_hexdump_nospc(const unsigned char *buf, int len)
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#if defined(__MACH__) && defined(__APPLE__)
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;
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#else
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__attribute__((weak, alias("osmo_hexdump_nospc")));
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#endif
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#include <ctype.h>
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/*! Convert an entire string to lower case
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* \param[out] out output string, caller-allocated
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* \param[in] in input string
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*/
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void osmo_str2lower(char *out, const char *in)
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{
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unsigned int i;
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for (i = 0; i < strlen(in); i++)
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out[i] = tolower((const unsigned char)in[i]);
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out[strlen(in)] = '\0';
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}
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/*! Convert an entire string to upper case
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* \param[out] out output string, caller-allocated
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* \param[in] in input string
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*/
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void osmo_str2upper(char *out, const char *in)
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{
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unsigned int i;
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for (i = 0; i < strlen(in); i++)
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out[i] = toupper((const unsigned char)in[i]);
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out[strlen(in)] = '\0';
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}
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/*! Wishful thinking to generate a constant time compare
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* \param[in] exp Expected data
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* \param[in] rel Comparison value
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* \param[in] count Number of bytes to compare
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* \returns 1 in case \a exp equals \a rel; zero otherwise
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*
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* Compare count bytes of exp to rel. Return 0 if they are identical, 1
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* otherwise. Do not return a mismatch on the first mismatching byte,
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* but always compare all bytes, regardless. The idea is that the amount of
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* matching bytes cannot be inferred from the time the comparison took. */
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int osmo_constant_time_cmp(const uint8_t *exp, const uint8_t *rel, const int count)
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{
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int x = 0, i;
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for (i = 0; i < count; ++i)
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x |= exp[i] ^ rel[i];
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/* if x is zero, all data was identical */
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return x? 1 : 0;
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}
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/*! Generic retrieval of 1..8 bytes as big-endian uint64_t
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* \param[in] data Input data as byte-array
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* \param[in] data_len Length of \a data in octets
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* \returns uint64_t of \a data interpreted as big-endian
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*
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* This is like osmo_load64be_ext, except that if data_len is less than
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* sizeof(uint64_t), the data is interpreted as the least significant bytes
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* (osmo_load64be_ext loads them as the most significant bytes into the
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* returned uint64_t). In this way, any integer size up to 64 bits can be
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* decoded conveniently by using sizeof(), without the need to call specific
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* numbered functions (osmo_load16, 32, ...). */
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uint64_t osmo_decode_big_endian(const uint8_t *data, size_t data_len)
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{
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uint64_t value = 0;
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while (data_len > 0) {
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value = (value << 8) + *data;
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data += 1;
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data_len -= 1;
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}
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return value;
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}
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/*! Generic big-endian encoding of big endian number up to 64bit
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* \param[in] value unsigned integer value to be stored
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* \param[in] data_len number of octets
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* \returns static buffer containing big-endian stored value
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*
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* This is like osmo_store64be_ext, except that this returns a static buffer of
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* the result (for convenience, but not threadsafe). If data_len is less than
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* sizeof(uint64_t), only the least significant bytes of value are encoded. */
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uint8_t *osmo_encode_big_endian(uint64_t value, size_t data_len)
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{
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static uint8_t buf[sizeof(uint64_t)];
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OSMO_ASSERT(data_len <= ARRAY_SIZE(buf));
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osmo_store64be_ext(value, buf, data_len);
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return buf;
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}
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/*! Copy a C-string into a sized buffer
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* \param[in] src source string
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* \param[out] dst destination string
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* \param[in] siz size of the \a dst buffer
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* \returns length of \a src
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*
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* Copy at most \a siz bytes from \a src to \a dst, ensuring that the result is
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* NUL terminated. The NUL character is included in \a siz, i.e. passing the
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* actual sizeof(*dst) is correct.
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*/
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size_t osmo_strlcpy(char *dst, const char *src, size_t siz)
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{
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size_t ret = src ? strlen(src) : 0;
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|
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if (siz) {
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size_t len = (ret >= siz) ? siz - 1 : ret;
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if (src)
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memcpy(dst, src, len);
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dst[len] = '\0';
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}
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return ret;
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}
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/*! Validate that a given string is a hex string within given size limits.
|
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* Note that each hex digit amounts to a nibble, so if checking for a hex
|
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* string to result in N bytes, pass amount of digits as 2*N.
|
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* \param str A nul-terminated string to validate, or NULL.
|
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* \param min_digits least permitted amount of digits.
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* \param max_digits most permitted amount of digits.
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* \param require_even if true, require an even amount of digits.
|
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* \returns true when the hex_str contains only hexadecimal digits (no
|
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* whitespace) and matches the requested length; also true
|
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* when min_digits <= 0 and str is NULL.
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*/
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bool osmo_is_hexstr(const char *str, int min_digits, int max_digits,
|
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bool require_even)
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{
|
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int len;
|
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/* Use unsigned char * to avoid a compiler warning of
|
||||
* "error: array subscript has type 'char' [-Werror=char-subscripts]" */
|
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const unsigned char *pos = (const unsigned char*)str;
|
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if (!pos)
|
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return min_digits < 1;
|
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for (len = 0; *pos && len < max_digits; len++, pos++)
|
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if (!isxdigit(*pos))
|
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return false;
|
||||
if (len < min_digits)
|
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return false;
|
||||
/* With not too many digits, we should have reached *str == nul */
|
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if (*pos)
|
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return false;
|
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if (require_even && (len & 1))
|
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return false;
|
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|
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return true;
|
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}
|
||||
|
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/*! Determine if a given identifier is valid, i.e. doesn't contain illegal chars
|
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* \param[in] str String to validate
|
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* \param[in] sep_chars Permitted separation characters between identifiers.
|
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* \returns true in case \a str contains only valid identifiers and sep_chars, false otherwise
|
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*/
|
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bool osmo_separated_identifiers_valid(const char *str, const char *sep_chars)
|
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{
|
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/* characters that are illegal in names */
|
||||
static const char illegal_chars[] = "., {}[]()<>|~\\^`'\"?=;/+*&%$#!";
|
||||
unsigned int i;
|
||||
size_t len;
|
||||
|
||||
/* an empty string is not a valid identifier */
|
||||
if (!str || (len = strlen(str)) == 0)
|
||||
return false;
|
||||
|
||||
for (i = 0; i < len; i++) {
|
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if (sep_chars && strchr(sep_chars, str[i]))
|
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continue;
|
||||
/* check for 7-bit ASCII */
|
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if (str[i] & 0x80)
|
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return false;
|
||||
if (!isprint((int)str[i]))
|
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return false;
|
||||
/* check for some explicit reserved control characters */
|
||||
if (strchr(illegal_chars, str[i]))
|
||||
return false;
|
||||
}
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
/*! Determine if a given identifier is valid, i.e. doesn't contain illegal chars
|
||||
* \param[in] str String to validate
|
||||
* \returns true in case \a str contains valid identifier, false otherwise
|
||||
*/
|
||||
bool osmo_identifier_valid(const char *str)
|
||||
{
|
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return osmo_separated_identifiers_valid(str, NULL);
|
||||
}
|
||||
|
||||
/*! Return the string with all non-printable characters escaped.
|
||||
* \param[in] str A string that may contain any characters.
|
||||
* \param[in] len Pass -1 to print until nul char, or >= 0 to force a length.
|
||||
* \param[inout] buf string buffer to write escaped characters to.
|
||||
* \param[in] bufsize size of \a buf.
|
||||
* \returns buf containing an escaped representation, possibly truncated, or str itself.
|
||||
*/
|
||||
const char *osmo_escape_str_buf(const char *str, int in_len, char *buf, size_t bufsize)
|
||||
{
|
||||
int in_pos = 0;
|
||||
int next_unprintable = 0;
|
||||
int out_pos = 0;
|
||||
char *out = buf;
|
||||
/* -1 to leave space for a final \0 */
|
||||
int out_len = bufsize-1;
|
||||
|
||||
if (!str)
|
||||
return "(null)";
|
||||
|
||||
if (in_len < 0)
|
||||
in_len = strlen(str);
|
||||
|
||||
while (in_pos < in_len) {
|
||||
for (next_unprintable = in_pos;
|
||||
next_unprintable < in_len && isprint((int)str[next_unprintable])
|
||||
&& str[next_unprintable] != '"'
|
||||
&& str[next_unprintable] != '\\';
|
||||
next_unprintable++);
|
||||
|
||||
if (next_unprintable == in_len
|
||||
&& in_pos == 0)
|
||||
return str;
|
||||
|
||||
while (in_pos < next_unprintable && out_pos < out_len)
|
||||
out[out_pos++] = str[in_pos++];
|
||||
|
||||
if (out_pos == out_len || in_pos == in_len)
|
||||
goto done;
|
||||
|
||||
switch (str[next_unprintable]) {
|
||||
#define BACKSLASH_CASE(c, repr) \
|
||||
case c: \
|
||||
if (out_pos > out_len-2) \
|
||||
goto done; \
|
||||
out[out_pos++] = '\\'; \
|
||||
out[out_pos++] = repr; \
|
||||
break
|
||||
|
||||
BACKSLASH_CASE('\n', 'n');
|
||||
BACKSLASH_CASE('\r', 'r');
|
||||
BACKSLASH_CASE('\t', 't');
|
||||
BACKSLASH_CASE('\0', '0');
|
||||
BACKSLASH_CASE('\a', 'a');
|
||||
BACKSLASH_CASE('\b', 'b');
|
||||
BACKSLASH_CASE('\v', 'v');
|
||||
BACKSLASH_CASE('\f', 'f');
|
||||
BACKSLASH_CASE('\\', '\\');
|
||||
BACKSLASH_CASE('"', '"');
|
||||
#undef BACKSLASH_CASE
|
||||
|
||||
default:
|
||||
out_pos += snprintf(&out[out_pos], out_len - out_pos, "\\%u", (unsigned char)str[in_pos]);
|
||||
if (out_pos > out_len) {
|
||||
out_pos = out_len;
|
||||
goto done;
|
||||
}
|
||||
break;
|
||||
}
|
||||
in_pos ++;
|
||||
}
|
||||
|
||||
done:
|
||||
out[out_pos] = '\0';
|
||||
return out;
|
||||
}
|
||||
|
||||
/*! Return the string with all non-printable characters escaped.
|
||||
* Call osmo_escape_str_buf() with a static buffer.
|
||||
* \param[in] str A string that may contain any characters.
|
||||
* \param[in] len Pass -1 to print until nul char, or >= 0 to force a length.
|
||||
* \returns buf containing an escaped representation, possibly truncated, or str itself.
|
||||
*/
|
||||
const char *osmo_escape_str(const char *str, int in_len)
|
||||
{
|
||||
return osmo_escape_str_buf(str, in_len, namebuf, sizeof(namebuf));
|
||||
}
|
||||
|
||||
/*! Like osmo_escape_str(), but returns double-quotes around a string, or "NULL" for a NULL string.
|
||||
* This allows passing any char* value and get its C representation as string.
|
||||
* \param[in] str A string that may contain any characters.
|
||||
* \param[in] len Pass -1 to print until nul char, or >= 0 to force a length.
|
||||
* \returns buf containing an escaped representation, possibly truncated, or str itself.
|
||||
*/
|
||||
const char *osmo_quote_str_buf(const char *str, int in_len, char *buf, size_t bufsize)
|
||||
{
|
||||
const char *res;
|
||||
int l;
|
||||
if (!str)
|
||||
return "NULL";
|
||||
if (bufsize < 3)
|
||||
return "<buf-too-small>";
|
||||
buf[0] = '"';
|
||||
res = osmo_escape_str_buf(str, in_len, buf + 1, bufsize - 2);
|
||||
/* if osmo_escape_str_buf() returned the str itself, we need to copy it to buf to be able to
|
||||
* quote it. */
|
||||
if (res == str) {
|
||||
/* max_len = bufsize - two quotes - nul term */
|
||||
int max_len = bufsize - 2 - 1;
|
||||
if (in_len >= 0)
|
||||
max_len = OSMO_MIN(in_len, max_len);
|
||||
/* It is not allowed to pass unterminated strings into osmo_strlcpy() :/ */
|
||||
strncpy(buf + 1, str, max_len);
|
||||
buf[1 + max_len] = '\0';
|
||||
}
|
||||
l = strlen(buf);
|
||||
buf[l] = '"';
|
||||
buf[l+1] = '\0'; /* both osmo_escape_str_buf() and max_len above ensure room for '\0' */
|
||||
return buf;
|
||||
}
|
||||
|
||||
const char *osmo_quote_str(const char *str, int in_len)
|
||||
{
|
||||
return osmo_quote_str_buf(str, in_len, namebuf, sizeof(namebuf));
|
||||
}
|
||||
|
||||
/*! perform an integer square root operation on unsigned 32bit integer.
|
||||
* This implementation is taken from "Hacker's Delight" Figure 11-1 "Integer square root, Newton's
|
||||
* method", which can also be found at http://www.hackersdelight.org/hdcodetxt/isqrt.c.txt */
|
||||
uint32_t osmo_isqrt32(uint32_t x)
|
||||
{
|
||||
uint32_t x1;
|
||||
int s, g0, g1;
|
||||
|
||||
if (x <= 1)
|
||||
return x;
|
||||
|
||||
s = 1;
|
||||
x1 = x - 1;
|
||||
if (x1 > 0xffff) {
|
||||
s = s + 8;
|
||||
x1 = x1 >> 16;
|
||||
}
|
||||
if (x1 > 0xff) {
|
||||
s = s + 4;
|
||||
x1 = x1 >> 8;
|
||||
}
|
||||
if (x1 > 0xf) {
|
||||
s = s + 2;
|
||||
x1 = x1 >> 4;
|
||||
}
|
||||
if (x1 > 0x3) {
|
||||
s = s + 1;
|
||||
}
|
||||
|
||||
g0 = 1 << s; /* g0 = 2**s */
|
||||
g1 = (g0 + (x >> s)) >> 1; /* g1 = (g0 + x/g0)/2 */
|
||||
|
||||
/* converges after four to five divisions for arguments up to 16,785,407 */
|
||||
while (g1 < g0) {
|
||||
g0 = g1;
|
||||
g1 = (g0 + (x/g0)) >> 1;
|
||||
}
|
||||
return g0;
|
||||
}
|
||||
|
||||
/*! @} */
|
||||
Reference in New Issue
Block a user