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Diffstat (limited to 'src/core/utils.c')
-rw-r--r-- | src/core/utils.c | 1586 |
1 files changed, 1586 insertions, 0 deletions
diff --git a/src/core/utils.c b/src/core/utils.c new file mode 100644 index 00000000..1ec940d0 --- /dev/null +++ b/src/core/utils.c @@ -0,0 +1,1586 @@ +/* + * (C) 2011 by Harald Welte <laforge@gnumonks.org> + * (C) 2011 by Sylvain Munaut <tnt@246tNt.com> + * (C) 2014 by Nils O. SelÄsdal <noselasd@fiane.dyndns.org> + * + * All Rights Reserved + * + * SPDX-License-Identifier: GPL-2.0+ + * + * 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. + * + */ + + +#include <stdbool.h> +#include <string.h> +#include <stdint.h> +#include <errno.h> +#include <stdio.h> +#include <inttypes.h> +#include <limits.h> + +#include <osmocom/core/utils.h> +#include <osmocom/core/bit64gen.h> + + +/*! \addtogroup utils + * @{ + * various utility routines + * + * \file utils.c */ + +static __thread char namebuf[255]; +/* shared by osmo_str_tolower() and osmo_str_toupper() */ +static __thread char capsbuf[128]; + +/*! get human-readable string for given value + * \param[in] vs Array of value_string tuples + * \param[in] val Value to be converted + * \returns pointer to human-readable string + * + * If val is found in vs, the array's string entry is returned. Otherwise, an + * "unknown" string containing the actual value is composed in a static buffer + * that is reused across invocations. + */ +const char *get_value_string(const struct value_string *vs, uint32_t val) +{ + const char *str = get_value_string_or_null(vs, val); + if (str) + return str; + + snprintf(namebuf, sizeof(namebuf), "unknown 0x%"PRIx32, val); + namebuf[sizeof(namebuf) - 1] = '\0'; + return namebuf; +} + +/*! get human-readable string or NULL for given value + * \param[in] vs Array of value_string tuples + * \param[in] val Value to be converted + * \returns pointer to human-readable string or NULL if val is not found + */ +const char *get_value_string_or_null(const struct value_string *vs, + uint32_t val) +{ + int i; + + if (!vs) + return NULL; + + for (i = 0;; i++) { + if (vs[i].value == 0 && vs[i].str == NULL) + break; + if (vs[i].value == val) + return vs[i].str; + } + + return NULL; +} + +/*! get numeric value for given human-readable string + * \param[in] vs Array of value_string tuples + * \param[in] str human-readable string + * \returns numeric value (>0) or negative numer in case of error + */ +int get_string_value(const struct value_string *vs, const char *str) +{ + int i; + + for (i = 0;; i++) { + if (vs[i].value == 0 && vs[i].str == NULL) + break; + if (!strcasecmp(vs[i].str, str)) + return vs[i].value; + } + return -EINVAL; +} + +/*! Convert BCD-encoded digit into printable character + * \param[in] bcd A single BCD-encoded digit + * \returns single printable character + */ +char osmo_bcd2char(uint8_t bcd) +{ + if (bcd < 0xa) + return '0' + bcd; + else + return 'A' + (bcd - 0xa); +} + +/*! Convert number in ASCII to BCD value + * \param[in] c ASCII character + * \returns BCD encoded value of character + */ +uint8_t osmo_char2bcd(char c) +{ + if (c >= '0' && c <= '9') + return c - 0x30; + else if (c >= 'A' && c <= 'F') + return 0xa + (c - 'A'); + else if (c >= 'a' && c <= 'f') + return 0xa + (c - 'a'); + else + return 0; +} + +/*! Convert BCD to string. + * The given nibble offsets are interpreted in BCD order, i.e. nibble 0 is bcd[0] & 0xf, nibble 1 is bcd[0] >> 4, nibble + * 3 is bcd[1] & 0xf, etc.. + * \param[out] dst Output string buffer, is always nul terminated when dst_size > 0. + * \param[in] dst_size sizeof() the output string buffer. + * \param[in] bcd Binary coded data buffer. + * \param[in] start_nibble Offset to start from, in nibbles, typically 1 to skip the first nibble. + * \param[in] end_nibble Offset to stop before, in nibbles, e.g. sizeof(bcd)*2 - (bcd[0] & GSM_MI_ODD? 0:1). + * \param[in] allow_hex If false, return error if there are digits other than 0-9. If true, return those as [A-F]. + * \returns The strlen that would be written if the output buffer is large enough, excluding nul byte (like + * snprintf()), or -EINVAL if allow_hex is false and a digit > 9 is encountered. On -EINVAL, the conversion is + * still completed as if allow_hex were passed as true. Return -ENOMEM if dst is NULL or dst_size is zero. + * If end_nibble <= start_nibble, write an empty string to dst and return 0. + */ +int osmo_bcd2str(char *dst, size_t dst_size, const uint8_t *bcd, int start_nibble, int end_nibble, bool allow_hex) +{ + char *dst_end; + int nibble_i; + int rc = 0; + + if (!dst || dst_size < 1 || start_nibble < 0) + return -ENOMEM; + + dst_end = dst + dst_size - 1; + + for (nibble_i = start_nibble; nibble_i < end_nibble && dst < dst_end; nibble_i++, dst++) { + uint8_t nibble = bcd[nibble_i >> 1]; + if ((nibble_i & 1)) + nibble >>= 4; + nibble &= 0xf; + + if (!allow_hex && nibble > 9) + rc = -EINVAL; + + *dst = osmo_bcd2char(nibble); + } + *dst = '\0'; + + if (rc < 0) + return rc; + return OSMO_MAX(0, end_nibble - start_nibble); +} + +/*! Convert string to BCD. + * The given nibble offsets are interpreted in BCD order, i.e. nibble 0 is bcd[0] & 0x0f, nibble 1 is bcd[0] & 0xf0, nibble + * 3 is bcd[1] & 0x0f, etc.. + * \param[out] dst Output BCD buffer. + * \param[in] dst_size sizeof() the output string buffer. + * \param[in] digits String containing decimal or hexadecimal digits in upper or lower case. + * \param[in] start_nibble Offset to start from, in nibbles, typically 1 to skip the first (MI type) nibble. + * \param[in] end_nibble Negative to write all digits found in str, followed by 0xf nibbles to fill any started octet. + * If >= 0, stop before this offset in nibbles, e.g. to get default behavior, pass + * start_nibble + strlen(str) + ((start_nibble + strlen(str)) & 1? 1 : 0) + 1. + * \param[in] allow_hex If false, return error if there are hexadecimal digits (A-F). If true, write those to + * BCD. + * \returns The buffer size in octets that is used to place all bcd digits (including the skipped nibbles + * from 'start_nibble' and rounded up to full octets); -EINVAL on invalid digits; + * -ENOMEM if dst is NULL, if dst_size is too small to contain all nibbles, or if start_nibble is negative. + */ +int osmo_str2bcd(uint8_t *dst, size_t dst_size, const char *digits, int start_nibble, int end_nibble, bool allow_hex) +{ + const char *digit = digits; + int nibble_i; + + if (!dst || !dst_size || start_nibble < 0) + return -ENOMEM; + + if (end_nibble < 0) { + end_nibble = start_nibble + strlen(digits); + /* If the last octet is not complete, add another filler nibble */ + if (end_nibble & 1) + end_nibble++; + } + if ((unsigned int) (end_nibble / 2) > dst_size) + return -ENOMEM; + + for (nibble_i = start_nibble; nibble_i < end_nibble; nibble_i++) { + uint8_t nibble = 0xf; + int octet = nibble_i >> 1; + if (*digit) { + char c = *digit; + digit++; + if (c >= '0' && c <= '9') + nibble = c - '0'; + else if (allow_hex && c >= 'A' && c <= 'F') + nibble = 0xa + (c - 'A'); + else if (allow_hex && c >= 'a' && c <= 'f') + nibble = 0xa + (c - 'a'); + else + return -EINVAL; + } + nibble &= 0xf; + if ((nibble_i & 1)) + dst[octet] = (nibble << 4) | (dst[octet] & 0x0f); + else + dst[octet] = (dst[octet] & 0xf0) | nibble; + } + + /* floor(float(end_nibble) / 2) */ + return end_nibble / 2; +} + +/*! Parse a string containing hexadecimal digits + * \param[in] str string containing ASCII encoded hexadecimal digits + * \param[out] b output buffer + * \param[in] max_len maximum space in output buffer + * \returns number of parsed octets, or -1 on error + */ +int osmo_hexparse(const char *str, uint8_t *b, unsigned int max_len) + +{ + char c; + uint8_t v; + const char *strpos; + unsigned int nibblepos = 0; + + memset(b, 0x00, max_len); + + for (strpos = str; (c = *strpos); strpos++) { + /* skip whitespace */ + if (c == ' ' || c == '\t' || c == '\n' || c == '\r') + continue; + + /* If the buffer is too small, error out */ + if (nibblepos >= (max_len << 1)) + return -1; + + if (c >= '0' && c <= '9') + v = c - '0'; + else if (c >= 'a' && c <= 'f') + v = 10 + (c - 'a'); + else if (c >= 'A' && c <= 'F') + v = 10 + (c - 'A'); + else + return -1; + + b[nibblepos >> 1] |= v << (nibblepos & 1 ? 0 : 4); + nibblepos ++; + } + + /* In case of uneven amount of digits, the last byte is not complete + * and that's an error. */ + if (nibblepos & 1) + return -1; + + return nibblepos >> 1; +} + +static __thread char hexd_buff[4096]; +static const char hex_chars[] = "0123456789abcdef"; + +/*! Convert binary sequence to hexadecimal ASCII string. + * \param[out] out_buf Output buffer to write the resulting string to. + * \param[in] out_buf_size sizeof(out_buf). + * \param[in] buf Input buffer, pointer to sequence of bytes. + * \param[in] len Length of input buf in number of bytes. + * \param[in] delim String to separate each byte; NULL or "" for no delim. + * \param[in] delim_after_last If true, end the string in delim (true: "1a:ef:d9:", false: "1a:ef:d9"); + * if out_buf has insufficient space, the string will always end in a delim. + * \returns out_buf, containing a zero-terminated string, or "" (empty string) if out_buf == NULL or out_buf_size < 1. + * + * This function will print a sequence of bytes as hexadecimal numbers, adding one delim between each byte (e.g. for + * delim passed as ":", return a string like "1a:ef:d9"). + * + * The delim_after_last argument exists to be able to exactly show the original osmo_hexdump() behavior, which always + * ends the string with a delimiter. + */ +const char *osmo_hexdump_buf(char *out_buf, size_t out_buf_size, const unsigned char *buf, int len, const char *delim, + bool delim_after_last) +{ + int i; + char *cur = out_buf; + size_t delim_len; + + if (!out_buf || !out_buf_size) + return ""; + + delim = delim ? : ""; + delim_len = strlen(delim); + + for (i = 0; i < len; i++) { + const char *delimp = delim; + int len_remain = out_buf_size - (cur - out_buf) - 1; + if (len_remain < (int) (2 + delim_len) + && !(!delim_after_last && i == (len - 1) && len_remain >= 2)) + break; + + *cur++ = hex_chars[buf[i] >> 4]; + *cur++ = hex_chars[buf[i] & 0xf]; + + if (i == (len - 1) && !delim_after_last) + break; + + while (len_remain > 1 && *delimp) { + *cur++ = *delimp++; + len_remain--; + } + } + *cur = '\0'; + return out_buf; +} + +/*! Convert a sequence of unpacked bits to ASCII string, in user-supplied buffer. + * \param[out] buf caller-provided output string buffer + * \param[out] buf_len size of buf in bytes + * \param[in] bits A sequence of unpacked bits + * \param[in] len Length of bits + * \return The output buffer (buf). + */ +char *osmo_ubit_dump_buf(char *buf, size_t buf_len, const uint8_t *bits, unsigned int len) +{ + unsigned int i; + + if (len > buf_len-1) + len = buf_len-1; + memset(buf, 0, buf_len); + + for (i = 0; i < len; i++) { + char outch; + switch (bits[i]) { + case 0: + outch = '0'; + break; + case 0xff: + outch = '?'; + break; + case 1: + outch = '1'; + break; + default: + outch = 'E'; + break; + } + buf[i] = outch; + } + buf[buf_len-1] = 0; + return buf; +} + +/*! Convert a sequence of unpacked bits to ASCII string, in static buffer. + * \param[in] bits A sequence of unpacked bits + * \param[in] len Length of bits + * \returns string representation in static buffer. + */ +char *osmo_ubit_dump(const uint8_t *bits, unsigned int len) +{ + return osmo_ubit_dump_buf(hexd_buff, sizeof(hexd_buff), bits, len); +} + +/*! Convert binary sequence to hexadecimal ASCII string + * \param[in] buf pointer to sequence of bytes + * \param[in] len length of buf in number of bytes + * \returns pointer to zero-terminated string + * + * This function will print a sequence of bytes as hexadecimal numbers, + * adding one space character between each byte (e.g. "1a ef d9") + * + * The maximum size of the output buffer is 4096 bytes, i.e. the maximum + * number of input bytes that can be printed in one call is 1365! + */ +char *osmo_hexdump(const unsigned char *buf, int len) +{ + osmo_hexdump_buf(hexd_buff, sizeof(hexd_buff), buf, len, " ", true); + return hexd_buff; +} + +/*! Convert binary sequence to hexadecimal ASCII string + * \param[in] ctx talloc context from where to allocate the output string + * \param[in] buf pointer to sequence of bytes + * \param[in] len length of buf in number of bytes + * \returns pointer to zero-terminated string + * + * This function will print a sequence of bytes as hexadecimal numbers, + * adding one space character between each byte (e.g. "1a ef d9") + */ +char *osmo_hexdump_c(const void *ctx, const unsigned char *buf, int len) +{ + size_t hexd_buff_len = len * 3 + 1; + char *hexd_buff = talloc_size(ctx, hexd_buff_len); + if (!hexd_buff) + return NULL; + osmo_hexdump_buf(hexd_buff, hexd_buff_len, buf, len, " ", true); + return hexd_buff; +} + +/*! Convert binary sequence to hexadecimal ASCII string + * \param[in] buf pointer to sequence of bytes + * \param[in] len length of buf in number of bytes + * \returns pointer to zero-terminated string + * + * This function will print a sequence of bytes as hexadecimal numbers, + * without any space character between each byte (e.g. "1aefd9") + * + * The maximum size of the output buffer is 4096 bytes, i.e. the maximum + * number of input bytes that can be printed in one call is 2048! + */ +char *osmo_hexdump_nospc(const unsigned char *buf, int len) +{ + osmo_hexdump_buf(hexd_buff, sizeof(hexd_buff), buf, len, "", true); + return hexd_buff; +} + +/*! Convert binary sequence to hexadecimal ASCII string + * \param[in] ctx talloc context from where to allocate the output string + * \param[in] buf pointer to sequence of bytes + * \param[in] len length of buf in number of bytes + * \returns pointer to zero-terminated string + * + * This function will print a sequence of bytes as hexadecimal numbers, + * without any space character between each byte (e.g. "1aefd9") + */ +char *osmo_hexdump_nospc_c(const void *ctx, const unsigned char *buf, int len) +{ + size_t hexd_buff_len = len * 2 + 1; + char *hexd_buff = talloc_size(ctx, hexd_buff_len); + if (!hexd_buff) + return NULL; + osmo_hexdump_buf(hexd_buff, hexd_buff_len, buf, len, "", true); + return hexd_buff; +} + + +/* Compat with previous typo to preserve abi */ +char *osmo_osmo_hexdump_nospc(const unsigned char *buf, int len) +#if defined(__MACH__) && defined(__APPLE__) + ; +#else + __attribute__((weak, alias("osmo_hexdump_nospc"))); +#endif + +#include "config.h" +#ifdef HAVE_CTYPE_H +#include <ctype.h> +/*! Convert an entire string to lower case + * \param[out] out output string, caller-allocated + * \param[in] in input string + */ +void osmo_str2lower(char *out, const char *in) +{ + unsigned int i; + + for (i = 0; i < strlen(in); i++) + out[i] = tolower((const unsigned char)in[i]); + out[strlen(in)] = '\0'; +} + +/*! Convert an entire string to upper case + * \param[out] out output string, caller-allocated + * \param[in] in input string + */ +void osmo_str2upper(char *out, const char *in) +{ + unsigned int i; + + for (i = 0; i < strlen(in); i++) + out[i] = toupper((const unsigned char)in[i]); + out[strlen(in)] = '\0'; +} +#endif /* HAVE_CTYPE_H */ + +/*! Wishful thinking to generate a constant time compare + * \param[in] exp Expected data + * \param[in] rel Comparison value + * \param[in] count Number of bytes to compare + * \returns 1 in case \a exp equals \a rel; zero otherwise + * + * Compare count bytes of exp to rel. Return 0 if they are identical, 1 + * otherwise. Do not return a mismatch on the first mismatching byte, + * but always compare all bytes, regardless. The idea is that the amount of + * matching bytes cannot be inferred from the time the comparison took. */ +int osmo_constant_time_cmp(const uint8_t *exp, const uint8_t *rel, const int count) +{ + int x = 0, i; + + for (i = 0; i < count; ++i) + x |= exp[i] ^ rel[i]; + + /* if x is zero, all data was identical */ + return x? 1 : 0; +} + +/*! Generic retrieval of 1..8 bytes as big-endian uint64_t + * \param[in] data Input data as byte-array + * \param[in] data_len Length of \a data in octets + * \returns uint64_t of \a data interpreted as big-endian + * + * This is like osmo_load64be_ext, except that if data_len is less than + * sizeof(uint64_t), the data is interpreted as the least significant bytes + * (osmo_load64be_ext loads them as the most significant bytes into the + * returned uint64_t). In this way, any integer size up to 64 bits can be + * decoded conveniently by using sizeof(), without the need to call specific + * numbered functions (osmo_load16, 32, ...). */ +uint64_t osmo_decode_big_endian(const uint8_t *data, size_t data_len) +{ + uint64_t value = 0; + + while (data_len > 0) { + value = (value << 8) + *data; + data += 1; + data_len -= 1; + } + + return value; +} + +/*! Generic big-endian encoding of big endian number up to 64bit + * \param[in] value unsigned integer value to be stored + * \param[in] data_len number of octets + * \returns static buffer containing big-endian stored value + * + * This is like osmo_store64be_ext, except that this returns a static buffer of + * the result (for convenience, but not threadsafe). If data_len is less than + * sizeof(uint64_t), only the least significant bytes of value are encoded. */ +uint8_t *osmo_encode_big_endian(uint64_t value, size_t data_len) +{ + static __thread uint8_t buf[sizeof(uint64_t)]; + OSMO_ASSERT(data_len <= ARRAY_SIZE(buf)); + osmo_store64be_ext(value, buf, data_len); + return buf; +} + +/*! Copy a C-string into a sized buffer + * \param[in] src source string + * \param[out] dst destination string + * \param[in] siz size of the \a dst buffer + * \returns length of \a src + * + * Copy at most \a siz bytes from \a src to \a dst, ensuring that the result is + * NUL terminated. The NUL character is included in \a siz, i.e. passing the + * actual sizeof(*dst) is correct. + * + * Note, a similar function that also limits the input buffer size is osmo_print_n(). + */ +size_t osmo_strlcpy(char *dst, const char *src, size_t siz) +{ + size_t ret = src ? strlen(src) : 0; + + if (siz) { + size_t len = OSMO_MIN(siz - 1, ret); + if (len) + memcpy(dst, src, len); + dst[len] = '\0'; + } + return ret; +} + +/*! Find first occurence of a char in a size limited string. + * Like strchr() but with a buffer size limit. + * \param[in] str String buffer to examine. + * \param[in] str_size sizeof(str). + * \param[in] c Character to look for. + * \return Pointer to the matched char, or NULL if not found. + */ +const char *osmo_strnchr(const char *str, size_t str_size, char c) +{ + const char *end = str + str_size; + const char *pos; + if (!str) + return NULL; + for (pos = str; pos < end; pos++) { + if (c == *pos) + return pos; + if (!*pos) + return NULL; + } + return NULL; +} + +/*! Validate that a given string is a hex string within given size limits. + * Note that each hex digit amounts to a nibble, so if checking for a hex + * string to result in N bytes, pass amount of digits as 2*N. + * \param str A nul-terminated string to validate, or NULL. + * \param min_digits least permitted amount of digits. + * \param max_digits most permitted amount of digits. + * \param require_even if true, require an even amount of digits. + * \returns true when the hex_str contains only hexadecimal digits (no + * whitespace) and matches the requested length; also true + * when min_digits <= 0 and str is NULL. + */ +bool osmo_is_hexstr(const char *str, int min_digits, int max_digits, + bool require_even) +{ + int len; + /* Use unsigned char * to avoid a compiler warning of + * "error: array subscript has type 'char' [-Werror=char-subscripts]" */ + const unsigned char *pos = (const unsigned char*)str; + if (!pos) + return min_digits < 1; + for (len = 0; *pos && len < max_digits; len++, pos++) + if (!isxdigit(*pos)) + return false; + if (len < min_digits) + return false; + /* With not too many digits, we should have reached *str == nul */ + if (*pos) + return false; + if (require_even && (len & 1)) + return false; + + return true; +} + +static const char osmo_identifier_illegal_chars[] = "., {}[]()<>|~\\^`'\"?=;/+*&%$#!"; + +/*! Determine if a given identifier is valid, i.e. doesn't contain illegal chars + * \param[in] str String to validate + * \param[in] sep_chars Permitted separation characters between identifiers. + * \returns true in case \a str contains only valid identifiers and sep_chars, false otherwise + */ +bool osmo_separated_identifiers_valid(const char *str, const char *sep_chars) +{ + /* characters that are illegal in names */ + 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++) { + if (sep_chars && strchr(sep_chars, str[i])) + continue; + /* check for 7-bit ASCII */ + if (str[i] & 0x80) + return false; + if (!isprint((int)str[i])) + return false; + /* check for some explicit reserved control characters */ + if (strchr(osmo_identifier_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) +{ + return osmo_separated_identifiers_valid(str, NULL); +} + +/*! Replace characters in the given string buffer so that it is guaranteed to pass osmo_separated_identifiers_valid(). + * To guarantee passing osmo_separated_identifiers_valid(), replace_with must not itself be an illegal character. If in + * doubt, use '-'. + * \param[inout] str Identifier to sanitize, must be nul terminated and in a writable buffer. + * \param[in] sep_chars Additional characters that are to be replaced besides osmo_identifier_illegal_chars. + * \param[in] replace_with Replace any illegal characters with this character. + */ +void osmo_identifier_sanitize_buf(char *str, const char *sep_chars, char replace_with) +{ + char *pos; + if (!str) + return; + for (pos = str; *pos; pos++) { + if (strchr(osmo_identifier_illegal_chars, *pos) + || (sep_chars && strchr(sep_chars, *pos))) + *pos = replace_with; + } +} + +/*! Like osmo_escape_str_buf2, but with unusual ordering of arguments, and may sometimes return string constants instead + * of writing to buf for error cases or empty input. + * Most *_buf() functions have the buffer and size as first arguments, here the arguments are last. + * In particular, this function signature doesn't work with OSMO_STRBUF_APPEND_NOLEN(). + * \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 "(null)" if str == NULL, or "(error)" in case of errors. + */ +const char *osmo_escape_str_buf(const char *str, int in_len, char *buf, size_t bufsize) +{ + if (!str) + return "(null)"; + if (!buf || !bufsize) + return "(error)"; + return osmo_escape_str_buf2(buf, bufsize, str, in_len); +} + +/*! Copy N characters to a buffer with a function signature useful for OSMO_STRBUF_APPEND(). + * Similarly to snprintf(), the result is always nul terminated (except if buf is NULL or bufsize is 0). + * \param[out] buf Target buffer. + * \param[in] bufsize sizeof(buf). + * \param[in] str String to copy. + * \param[in] n Maximum number of non-nul characters to copy. + * \return Number of characters that would be written if bufsize were large enough excluding '\0' (like snprintf()). + */ +int osmo_print_n(char *buf, size_t bufsize, const char *str, size_t n) +{ + size_t write_n; + + if (!str) + str = ""; + + n = strnlen(str, n); + + if (!buf || !bufsize) + return n; + write_n = n; + if (write_n >= bufsize) + write_n = bufsize - 1; + if (write_n) + strncpy(buf, str, write_n); + buf[write_n] = '\0'; + + return n; +} + +/*! Return the string with all non-printable characters escaped. + * This internal function is the implementation for all osmo_escape_str* and osmo_quote_str* API versions. + * It provides both the legacy (non C compatible) escaping, as well as C compatible string constant syntax, + * and it provides a return value of characters-needed, to allow producing un-truncated strings in all cases. + * \param[out] buf string buffer to write escaped characters to. + * \param[in] bufsize sizeof(buf). + * \param[in] str A string that may contain any characters. + * \param[in] in_len Pass -1 to print until nul char, or >= 0 to force a length (also past nul chars). + * \param[in] legacy_format If false, return C compatible string constants ("\x0f"), if true the legacy + * escaping format ("\15"). The legacy format also escapes as "\a\b\f\v", while + * the non-legacy format also escapes those as "\xNN" sequences. + * \return Number of characters that would be written if bufsize were large enough excluding '\0' (like snprintf()). + */ +static int _osmo_escape_str_buf(char *buf, size_t bufsize, const char *str, int in_len, bool legacy_format) +{ + struct osmo_strbuf sb = { .buf = buf, .len = bufsize }; + int in_pos = 0; + int next_unprintable = 0; + + if (!str) + in_len = 0; + + if (in_len < 0) + in_len = strlen(str); + + /* Make sure of '\0' termination */ + if (!in_len) + OSMO_STRBUF_PRINTF(sb, "%s", ""); + + 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++); + + OSMO_STRBUF_APPEND(sb, osmo_print_n, &str[in_pos], next_unprintable - in_pos); + in_pos = next_unprintable; + + if (in_pos == in_len) + goto done; + + switch (str[next_unprintable]) { +#define BACKSLASH_CASE(c, repr) \ + case c: \ + OSMO_STRBUF_PRINTF(sb, "\\%c", repr); \ + break + + BACKSLASH_CASE('\n', 'n'); + BACKSLASH_CASE('\r', 'r'); + BACKSLASH_CASE('\t', 't'); + BACKSLASH_CASE('\0', '0'); + BACKSLASH_CASE('\\', '\\'); + BACKSLASH_CASE('"', '"'); + + default: + if (legacy_format) { + switch (str[next_unprintable]) { + BACKSLASH_CASE('\a', 'a'); + BACKSLASH_CASE('\b', 'b'); + BACKSLASH_CASE('\v', 'v'); + BACKSLASH_CASE('\f', 'f'); + default: + OSMO_STRBUF_PRINTF(sb, "\\%u", (unsigned char)str[in_pos]); + break; + } + break; + } + + OSMO_STRBUF_PRINTF(sb, "\\x%02x", (unsigned char)str[in_pos]); + break; + } + in_pos ++; +#undef BACKSLASH_CASE + } + +done: + return sb.chars_needed; +} + +/*! Return the string with all non-printable characters escaped. + * \param[out] buf string buffer to write escaped characters to. + * \param[in] bufsize sizeof(buf). + * \param[in] str A string that may contain any characters. + * \param[in] in_len Pass -1 to print until nul char, or >= 0 to force a length (also past nul chars). + * \return Number of characters that would be written if bufsize were large enough excluding '\0' (like snprintf()). + */ +int osmo_escape_str_buf3(char *buf, size_t bufsize, const char *str, int in_len) +{ + return _osmo_escape_str_buf(buf, bufsize, str, in_len, false); +} + +/*! Return the string with all non-printable characters escaped. + * \param[out] buf string buffer to write escaped characters to. + * \param[in] bufsize sizeof(buf). + * \param[in] str A string that may contain any characters. + * \param[in] in_len Pass -1 to print until nul char, or >= 0 to force a length (also past nul chars). + * \return The output buffer (buf). + */ +char *osmo_escape_str_buf2(char *buf, size_t bufsize, const char *str, int in_len) +{ + _osmo_escape_str_buf(buf, bufsize, str, in_len, true); + return buf; +} + +/*! 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)); +} + +/*! Return the string with all non-printable characters escaped, in dynamically-allocated 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 dynamically-allocated output buffer, containing an escaped representation + */ +char *osmo_escape_str_c(const void *ctx, const char *str, int in_len) +{ + /* The string will be at least as long as in_len, but some characters might need escaping. + * These extra bytes should catch most usual escaping situations, avoiding a second run in OSMO_NAME_C_IMPL. */ + OSMO_NAME_C_IMPL(ctx, in_len + 16, "ERROR", _osmo_escape_str_buf, str, in_len, true); +} + +/*! Return a quoted and escaped representation of the string. + * This internal function is the implementation for all osmo_quote_str* API versions. + * It provides both the legacy (non C compatible) escaping, as well as C compatible string constant syntax, + * and it provides a return value of characters-needed, to allow producing un-truncated strings in all cases. + * \param[out] buf string buffer to write escaped characters to. + * \param[in] bufsize sizeof(buf). + * \param[in] str A string that may contain any characters. + * \param[in] in_len Pass -1 to print until nul char, or >= 0 to force a length (also past nul chars). + * \param[in] legacy_format If false, return C compatible string constants ("\x0f"), if true the legacy + * escaping format ("\15"). The legacy format also escapes as "\a\b\f\v", while + * the non-legacy format also escapes those as "\xNN" sequences. + * \return Number of characters that would be written if bufsize were large enough excluding '\0' (like snprintf()). + */ +static size_t _osmo_quote_str_buf(char *buf, size_t bufsize, const char *str, int in_len, bool legacy_format) +{ + struct osmo_strbuf sb = { .buf = buf, .len = bufsize }; + if (!str) + OSMO_STRBUF_PRINTF(sb, "NULL"); + else { + OSMO_STRBUF_PRINTF(sb, "\""); + OSMO_STRBUF_APPEND(sb, _osmo_escape_str_buf, str, in_len, legacy_format); + OSMO_STRBUF_PRINTF(sb, "\""); + } + return sb.chars_needed; +} + +/*! Like osmo_escape_str_buf3(), 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. + * The function signature is suitable for OSMO_STRBUF_APPEND_NOLEN(). + * \param[out] buf string buffer to write escaped characters to. + * \param[in] bufsize sizeof(buf). + * \param[in] str A string that may contain any characters. + * \param[in] in_len Pass -1 to print until nul char, or >= 0 to force a length. + * \return Number of characters that would be written if bufsize were large enough excluding '\0' (like snprintf()). + */ +int osmo_quote_str_buf3(char *buf, size_t bufsize, const char *str, int in_len) +{ + return _osmo_quote_str_buf(buf, bufsize, str, in_len, false); +} + +/*! Like osmo_escape_str_buf2(), 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. + * The function signature is suitable for OSMO_STRBUF_APPEND_NOLEN(). + * \param[out] buf string buffer to write escaped characters to. + * \param[in] bufsize sizeof(buf). + * \param[in] str A string that may contain any characters. + * \param[in] in_len Pass -1 to print until nul char, or >= 0 to force a length. + * \return The output buffer (buf). + */ +char *osmo_quote_str_buf2(char *buf, size_t bufsize, const char *str, int in_len) +{ + _osmo_quote_str_buf(buf, bufsize, str, in_len, true); + return buf; +} + +/*! Like osmo_quote_str_buf2, but with unusual ordering of arguments, and may sometimes return string constants instead + * of writing to buf for error cases or empty input. + * Most *_buf() functions have the buffer and size as first arguments, here the arguments are last. + * In particular, this function signature doesn't work with OSMO_STRBUF_APPEND_NOLEN(). + * \param[in] str A string that may contain any characters. + * \param[in] in_len Pass -1 to print until nul char, or >= 0 to force a length. + * \returns buf containing a quoted and escaped representation, possibly truncated. + */ +const char *osmo_quote_str_buf(const char *str, int in_len, char *buf, size_t bufsize) +{ + if (!str) + return "NULL"; + if (!buf || !bufsize) + return "(error)"; + _osmo_quote_str_buf(buf, bufsize, str, in_len, true); + return buf; +} + +/*! Like osmo_quote_str_buf() but returns the result in a static buffer. + * The static buffer is shared with get_value_string() and osmo_escape_str(). + * \param[in] str A string that may contain any characters. + * \param[in] in_len Pass -1 to print until nul char, or >= 0 to force a length. + * \returns static buffer containing a quoted and escaped representation, possibly truncated. + */ +const char *osmo_quote_str(const char *str, int in_len) +{ + _osmo_quote_str_buf(namebuf, sizeof(namebuf), str, in_len, true); + return namebuf; +} + +/*! Like osmo_quote_str_buf() but returns the result in a dynamically-allocated buffer. + * \param[in] str A string that may contain any characters. + * \param[in] in_len Pass -1 to print until nul char, or >= 0 to force a length. + * \returns dynamically-allocated buffer containing a quoted and escaped representation. + */ +char *osmo_quote_str_c(const void *ctx, const char *str, int in_len) +{ + /* The string will be at least as long as in_len, but some characters might need escaping. + * These extra bytes should catch most usual escaping situations, avoiding a second run in OSMO_NAME_C_IMPL. */ + OSMO_NAME_C_IMPL(ctx, in_len + 16, "ERROR", _osmo_quote_str_buf, str, in_len, true); +} + +/*! Return the string with all non-printable characters escaped. + * In contrast to osmo_escape_str_buf2(), this returns the needed buffer size suitable for OSMO_STRBUF_APPEND(), and + * this escapes characters in a way compatible with C string constant syntax. + * \param[out] buf string buffer to write escaped characters to. + * \param[in] bufsize sizeof(buf). + * \param[in] str A string that may contain any characters. + * \param[in] in_len Pass -1 to print until nul char, or >= 0 to force a length (also past nul chars). + * \return Number of characters that would be written if bufsize were large enough excluding '\0' (like snprintf()). + */ +size_t osmo_escape_cstr_buf(char *buf, size_t bufsize, const char *str, int in_len) +{ + return _osmo_escape_str_buf(buf, bufsize, str, in_len, false); +} + +/*! Return the string with all non-printable characters escaped, in dynamically-allocated buffer. + * In contrast to osmo_escape_str_c(), this escapes characters in a way compatible with C string constant syntax, and + * allocates sufficient memory in all cases. + * \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 dynamically-allocated buffer, containing an escaped representation. + */ +char *osmo_escape_cstr_c(void *ctx, const char *str, int in_len) +{ + /* The string will be at least as long as in_len, but some characters might need escaping. + * These extra bytes should catch most usual escaping situations, avoiding a second run in OSMO_NAME_C_IMPL. */ + OSMO_NAME_C_IMPL(ctx, in_len + 16, "ERROR", _osmo_escape_str_buf, str, in_len, false); +} + +/*! Like osmo_escape_str_buf2(), 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. + * The function signature is suitable for OSMO_STRBUF_APPEND_NOLEN(). + * In contrast to osmo_escape_str_buf2(), this returns the needed buffer size suitable for OSMO_STRBUF_APPEND(), and + * this escapes characters in a way compatible with C string constant syntax. + * \param[out] buf string buffer to write escaped characters to. + * \param[in] bufsize sizeof(buf). + * \param[in] str A string that may contain any characters. + * \param[in] in_len Pass -1 to print until nul char, or >= 0 to force a length. + * \return Number of characters that would be written if bufsize were large enough excluding '\0' (like snprintf()). + */ +size_t osmo_quote_cstr_buf(char *buf, size_t bufsize, const char *str, int in_len) +{ + return _osmo_quote_str_buf(buf, bufsize, str, in_len, false); +} + +/*! Return the string quoted and with all non-printable characters escaped, in dynamically-allocated buffer. + * In contrast to osmo_quote_str_c(), this escapes characters in a way compatible with C string constant syntax, and + * allocates sufficient memory in all cases. + * \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 dynamically-allocated buffer, containing a quoted and escaped representation. + */ +char *osmo_quote_cstr_c(void *ctx, const char *str, int in_len) +{ + /* The string will be at least as long as in_len plus two quotes, but some characters might need escaping. + * These extra bytes should catch most usual escaping situations, avoiding a second run in OSMO_NAME_C_IMPL. */ + OSMO_NAME_C_IMPL(ctx, in_len + 16, "ERROR", _osmo_quote_str_buf, str, in_len, false); +} + +/*! 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; +} + +/*! Convert a string to lowercase, while checking buffer size boundaries. + * The result written to \a dest is guaranteed to be nul terminated if \a dest_len > 0. + * If dest == src, the string is converted in-place, if necessary truncated at dest_len - 1 characters + * length as well as nul terminated. + * Note: similar osmo_str2lower(), but safe to use for src strings of arbitrary length. + * \param[out] dest Target buffer to write lowercase string. + * \param[in] dest_len Maximum buffer size of dest (e.g. sizeof(dest)). + * \param[in] src String to convert to lowercase. + * \returns Length of \a src, like osmo_strlcpy(), but if \a dest == \a src at most \a dest_len - 1. + */ +size_t osmo_str_tolower_buf(char *dest, size_t dest_len, const char *src) +{ + size_t rc; + if (dest == src) { + if (dest_len < 1) + return 0; + dest[dest_len - 1] = '\0'; + rc = strlen(dest); + } else { + if (dest_len < 1) + return strlen(src); + rc = osmo_strlcpy(dest, src, dest_len); + } + for (; *dest; dest++) + *dest = tolower(*dest); + return rc; +} + +/*! Convert a string to lowercase, using a static buffer. + * The resulting string may be truncated if the internally used static buffer is shorter than src. + * The internal buffer is at least 128 bytes long, i.e. guaranteed to hold at least 127 characters and a + * terminating nul. The static buffer returned is shared with osmo_str_toupper(). + * See also osmo_str_tolower_buf(). + * \param[in] src String to convert to lowercase. + * \returns Resulting lowercase string in a static buffer, always nul terminated. + */ +const char *osmo_str_tolower(const char *src) +{ + osmo_str_tolower_buf(capsbuf, sizeof(capsbuf), src); + return capsbuf; +} + +/*! Convert a string to lowercase, dynamically allocating the output from given talloc context + * See also osmo_str_tolower_buf(). + * \param[in] ctx talloc context from where to allocate the output string + * \param[in] src String to convert to lowercase. + * \returns Resulting lowercase string in a dynamically allocated buffer, always nul terminated. + */ +char *osmo_str_tolower_c(const void *ctx, const char *src) +{ + size_t buf_len = strlen(src) + 1; + char *buf = talloc_size(ctx, buf_len); + if (!buf) + return NULL; + osmo_str_tolower_buf(buf, buf_len, src); + return buf; +} + +/*! Convert a string to uppercase, while checking buffer size boundaries. + * The result written to \a dest is guaranteed to be nul terminated if \a dest_len > 0. + * If dest == src, the string is converted in-place, if necessary truncated at dest_len - 1 characters + * length as well as nul terminated. + * Note: similar osmo_str2upper(), but safe to use for src strings of arbitrary length. + * \param[out] dest Target buffer to write uppercase string. + * \param[in] dest_len Maximum buffer size of dest (e.g. sizeof(dest)). + * \param[in] src String to convert to uppercase. + * \returns Length of \a src, like osmo_strlcpy(), but if \a dest == \a src at most \a dest_len - 1. + */ +size_t osmo_str_toupper_buf(char *dest, size_t dest_len, const char *src) +{ + size_t rc; + if (dest == src) { + if (dest_len < 1) + return 0; + dest[dest_len - 1] = '\0'; + rc = strlen(dest); + } else { + if (dest_len < 1) + return strlen(src); + rc = osmo_strlcpy(dest, src, dest_len); + } + for (; *dest; dest++) + *dest = toupper(*dest); + return rc; +} + +/*! Convert a string to uppercase, using a static buffer. + * The resulting string may be truncated if the internally used static buffer is shorter than src. + * The internal buffer is at least 128 bytes long, i.e. guaranteed to hold at least 127 characters and a + * terminating nul. The static buffer returned is shared with osmo_str_tolower(). + * See also osmo_str_toupper_buf(). + * \param[in] src String to convert to uppercase. + * \returns Resulting uppercase string in a static buffer, always nul terminated. + */ +const char *osmo_str_toupper(const char *src) +{ + osmo_str_toupper_buf(capsbuf, sizeof(capsbuf), src); + return capsbuf; +} + +/*! Convert a string to uppercase, dynamically allocating the output from given talloc context + * See also osmo_str_tolower_buf(). + * \param[in] ctx talloc context from where to allocate the output string + * \param[in] src String to convert to uppercase. + * \returns Resulting uppercase string in a dynamically allocated buffer, always nul terminated. + */ +char *osmo_str_toupper_c(const void *ctx, const char *src) +{ + size_t buf_len = strlen(src) + 1; + char *buf = talloc_size(ctx, buf_len); + if (!buf) + return NULL; + osmo_str_toupper_buf(buf, buf_len, src); + return buf; +} + +/*! Calculate the Luhn checksum (as used for IMEIs). + * \param[in] in Input digits in ASCII string representation. + * \param[in] in_len Count of digits to use for the input (14 for IMEI). + * \returns checksum char (e.g. '3'); negative on error + */ +char osmo_luhn(const char* in, int in_len) +{ + int i, sum = 0; + + /* All input must be numbers */ + for (i = 0; i < in_len; i++) { + if (!isdigit((unsigned char)in[i])) + return -EINVAL; + } + + /* Double every second digit and add it to sum */ + for (i = in_len - 1; i >= 0; i -= 2) { + int dbl = (in[i] - '0') * 2; + if (dbl > 9) + dbl -= 9; + sum += dbl; + } + + /* Add other digits to sum */ + for (i = in_len - 2; i >= 0; i -= 2) + sum += in[i] - '0'; + + /* Final checksum */ + return (sum * 9) % 10 + '0'; +} + +/*! Remove up to N chars from the end of an osmo_strbuf. + * |--char-count---| - - chars_needed - - | + * |<---------drop----------| + */ +void osmo_strbuf_drop_tail(struct osmo_strbuf *sb, size_t n_chars) +{ + size_t drop_n; + if (sb->pos <= sb->buf) + return; + drop_n = OSMO_MIN(sb->chars_needed, n_chars); + sb->chars_needed -= drop_n; + /* chars_needed was reduced by n_chars, which may have been entirely behind the end of a full buffer, within the + * hypothetical chars_needed. Modify the buffer tail pos only if the buffer is not or longer full now. */ + if (sb->chars_needed >= OSMO_STRBUF_CHAR_COUNT(*sb)) + return; + sb->pos = sb->buf + sb->chars_needed; + *sb->pos = '\0'; +} + +/*! Let osmo_strbuf know that n_chars characters (excluding nul) were written to the end of the buffer. + * If sb is nonempty, the n_chars are assumed to have been written to sb->pos. If sb is still empty and pos == NULL, the + * n_chars are assumed to have been written to the start of the buffer. + * Advance sb->pos and sb->chars_needed by at most n_chars, or up to sb->len - 1. + * Ensure nul termination. */ +void osmo_strbuf_added_tail(struct osmo_strbuf *sb, size_t n_chars) +{ + /* On init of an osmo_strbuf, sb->pos == NULL, which is defined as semantically identical to pointing at the + * start of the buffer. A caller may just write to the buffer and call osmo_strbuf_added_tail(), in which case + * still pos == NULL. pos != NULL happens as soon as the first OSMO_STRBUF_*() API has acted on the strbuf. */ + if (!sb->pos) + sb->pos = sb->buf; + sb->chars_needed += n_chars; + /* first get remaining space, not counting trailing nul; but safeguard against empty buffer */ + size_t n_added = OSMO_STRBUF_REMAIN(*sb); + if (n_added) + n_added--; + /* do not add more than fit in sb->len, still ensuring nul termination */ + n_added = OSMO_MIN(n_added, n_chars); + if (n_added) + sb->pos += n_added; + /* when a strbuf is full, sb->pos may point after the final nul, so nul terminate only when pos is valid. */ + if (sb->pos < sb->buf + sb->len) + *sb->pos = '\0'; +} + +/*! Compare start of a string. + * This is an optimisation of 'strstr(str, startswith_str) == str' because it doesn't search through the entire string. + * \param str (Longer) string to compare. + * \param startswith_str (Shorter) string to compare with the start of str. + * \return true iff the first characters of str fully match startswith_str or startswith_str is empty. */ +bool osmo_str_startswith(const char *str, const char *startswith_str) +{ + if (!startswith_str || !*startswith_str) + return true; + if (!str) + return false; + return strncmp(str, startswith_str, strlen(startswith_str)) == 0; +} + +/*! Convert a string of a floating point number to a signed int, with a decimal factor (fixed-point precision). + * For example, with precision=3, convert "-1.23" to -1230. In other words, the float value is multiplied by + * 10 to-the-power-of precision to obtain the returned integer. + * The usable range of digits is -INT64_MAX .. INT64_MAX -- note, not INT64_MIN! The value of INT64_MIN is excluded to + * reduce implementation complexity. See also utils_test.c. + * The advantage over using sscanf("%f") is guaranteed precision: float or double types may apply rounding in the + * conversion result. osmo_float_str_to_int() and osmo_int_to_float_str_buf() guarantee true results when converting + * back and forth between string and int. + * \param[out] val Returned integer value. + * \param[in] str String of a float, like '-12.345'. + * \param[in] precision Fixed-point precision, or * \returns 0 on success, negative on error. + */ +int osmo_float_str_to_int(int64_t *val, const char *str, unsigned int precision) +{ + const char *point; + char *endptr; + const char *p; + int64_t sign = 1; + int64_t integer = 0; + int64_t decimal = 0; + int64_t precision_factor; + int64_t integer_max; + int64_t decimal_max; + unsigned int i; + + OSMO_ASSERT(val); + *val = 0; + + if (!str) + return -EINVAL; + if (str[0] == '-') { + str = str + 1; + sign = -1; + } else if (str[0] == '+') { + str = str + 1; + } + if (!str[0]) + return -EINVAL; + + /* Validate entire string as purely digits and at most one decimal dot. If not doing this here in advance, + * parsing digits might stop early because of precision cut-off and miss validation of input data. */ + point = NULL; + for (p = str; *p; p++) { + if (*p == '.') { + if (point) + return -EINVAL; + point = p; + } else if (!isdigit((unsigned char)*p)) + return -EINVAL; + } + + /* Parse integer part if there is one. If the string starts with a point, there's nothing to parse for the + * integer part. */ + if (!point || point > str) { + errno = 0; + integer = strtoll(str, &endptr, 10); + if ((errno == ERANGE && (integer == LLONG_MAX || integer == LLONG_MIN)) + || (errno != 0 && integer == 0)) + return -ERANGE; + + if ((point && endptr != point) + || (!point && *endptr)) + return -EINVAL; + } + + /* Parse the fractional part if there is any, and if the precision is nonzero (if we even care about fractional + * digits) */ + if (precision && point && point[1] != '\0') { + /* limit the number of digits parsed to 'precision'. + * If 'precision' is larger than the 19 digits representable in int64_t, skip some, to pick up lower + * magnitude digits. */ + unsigned int skip_digits = (precision < 20) ? 0 : precision - 20; + char decimal_str[precision + 1]; + osmo_strlcpy(decimal_str, point+1, precision+1); + + /* fill with zeros to make exactly 'precision' digits */ + for (i = strlen(decimal_str); i < precision; i++) + decimal_str[i] = '0'; + decimal_str[precision] = '\0'; + + for (i = 0; i < skip_digits; i++) { + /* When skipping digits because precision > nr-of-digits-in-int64_t, they must be zero; + * if there is a nonzero digit above the precision, it's -ERANGE. */ + if (decimal_str[i] != '0') + return -ERANGE; + } + errno = 0; + decimal = strtoll(decimal_str + skip_digits, &endptr, 10); + if ((errno == ERANGE && (decimal == LLONG_MAX || decimal == LLONG_MIN)) + || (errno != 0 && decimal == 0)) + return -ERANGE; + + if (*endptr) + return -EINVAL; + } + + if (precision > 18) { + /* Special case of returning more digits than fit in int64_t range, e.g. + * osmo_float_str_to_int("0.0000000012345678901234567", precision=25) -> 12345678901234567. */ + precision_factor = 0; + integer_max = 0; + decimal_max = INT64_MAX; + } else { + /* Do not surpass the resulting int64_t range. Depending on the amount of precision, the integer part + * and decimal part have specific ranges they must comply to. */ + precision_factor = 1; + for (i = 0; i < precision; i++) + precision_factor *= 10; + integer_max = INT64_MAX / precision_factor; + if (integer == integer_max) + decimal_max = INT64_MAX % precision_factor; + else + decimal_max = INT64_MAX; + } + + if (integer > integer_max) + return -ERANGE; + if (decimal > decimal_max) + return -ERANGE; + + *val = sign * (integer * precision_factor + decimal); + return 0; +} + +/*! Convert an integer to a floating point string using a decimal quotient (fixed-point precision). + * For example, with precision = 3, convert -1230 to "-1.23". + * The usable range of digits is -INT64_MAX .. INT64_MAX -- note, not INT64_MIN! The value of INT64_MIN is excluded to + * reduce implementation complexity. See also utils_test.c. + * The advantage over using printf("%.6g") is guaranteed precision: float or double types may apply rounding in the + * conversion result. osmo_float_str_to_int() and osmo_int_to_float_str_buf() guarantee true results when converting + * back and forth between string and int. + * The resulting string omits trailing zeros in the fractional part (like "%g" would) but never applies rounding. + * \param[out] buf Buffer to write string to. + * \param[in] buflen sizeof(buf). + * \param[in] val Value to convert to float. + * \returns number of chars that would be written, like snprintf(). + */ +int osmo_int_to_float_str_buf(char *buf, size_t buflen, int64_t val, unsigned int precision) +{ + struct osmo_strbuf sb = { .buf = buf, .len = buflen }; + unsigned int i; + unsigned int w; + int64_t precision_factor; + if (val < 0) { + OSMO_STRBUF_PRINTF(sb, "-"); + if (val == INT64_MIN) { + OSMO_STRBUF_PRINTF(sb, "ERR"); + return sb.chars_needed; + } + val = -val; + } + + if (precision > 18) { + /* Special case of returning more digits than fit in int64_t range, e.g. + * osmo_int_to_float_str(12345678901234567, precision=25) -> "0.0000000012345678901234567". */ + if (!val) { + OSMO_STRBUF_PRINTF(sb, "0"); + return sb.chars_needed; + } + OSMO_STRBUF_PRINTF(sb, "0."); + for (i = 19; i < precision; i++) + OSMO_STRBUF_PRINTF(sb, "0"); + precision = 19; + } else { + precision_factor = 1; + for (i = 0; i < precision; i++) + precision_factor *= 10; + + OSMO_STRBUF_PRINTF(sb, "%" PRId64, val / precision_factor); + val %= precision_factor; + if (!val) + return sb.chars_needed; + OSMO_STRBUF_PRINTF(sb, "."); + } + + /* print fractional part, skip trailing zeros */ + w = precision; + while (!(val % 10)) { + val /= 10; + w--; + } + OSMO_STRBUF_PRINTF(sb, "%0*" PRId64, w, val); + return sb.chars_needed; +} + +/*! Convert an integer with a factor of a million to a floating point string. + * For example, convert -1230000 to "-1.23". + * \param[in] ctx Talloc ctx to allocate string buffer from. + * \param[in] val Value to convert to float. + * \returns resulting string, dynamically allocated. + */ +char *osmo_int_to_float_str_c(void *ctx, int64_t val, unsigned int precision) +{ + OSMO_NAME_C_IMPL(ctx, 16, "ERROR", osmo_int_to_float_str_buf, val, precision) +} + +/*! Convert a string of a number to int64_t, including all common strtoll() validity checks. + * It's not so trivial to call strtoll() and properly verify that the input string was indeed a valid number string. + * \param[out] result Buffer for the resulting integer number, or NULL if the caller is only interested in the + * validation result (returned rc). + * \param[in] str The string to convert. + * \param[in] base The integer base, i.e. 10 for decimal numbers or 16 for hexadecimal, as in strtoll(). + * \param[in] min_val The smallest valid number expected in the string. + * \param[in] max_val The largest valid number expected in the string. + * \return 0 on success, -EOVERFLOW if the number in the string exceeds int64_t, -ENOTSUPP if the base is not supported, + * -ERANGE if the converted number exceeds the range [min_val..max_val] but is still within int64_t range, -E2BIG if + * surplus characters follow after the number, -EINVAL if the string does not contain a number. In case of -ERANGE and + * -E2BIG, the converted number is still accurately returned in result. In case of -EOVERFLOW, the returned value is + * clamped to INT64_MIN..INT64_MAX. + */ +int osmo_str_to_int64(int64_t *result, const char *str, int base, int64_t min_val, int64_t max_val) +{ + long long int val; + char *endptr; + if (result) + *result = 0; + if (!str || !*str) + return -EINVAL; + errno = 0; + val = strtoll(str, &endptr, base); + /* In case the number string exceeds long long int range, strtoll() clamps the returned value to LLONG_MIN or + * LLONG_MAX. Make sure of the same here with respect to int64_t. */ + if (val < INT64_MIN) { + if (result) + *result = INT64_MIN; + return -ERANGE; + } + if (val > INT64_MAX) { + if (result) + *result = INT64_MAX; + return -ERANGE; + } + if (result) + *result = (int64_t)val; + switch (errno) { + case 0: + break; + case ERANGE: + return -EOVERFLOW; + default: + case EINVAL: + return -ENOTSUP; + } + if (!endptr || *endptr) { + /* No chars were converted */ + if (endptr == str) + return -EINVAL; + /* Or there are surplus chars after the converted number */ + return -E2BIG; + } + if (val < min_val || val > max_val) + return -ERANGE; + return 0; +} + +/*! Convert a string of a number to int, including all common strtoll() validity checks. + * Same as osmo_str_to_int64() but using the plain int data type. + * \param[out] result Buffer for the resulting integer number, or NULL if the caller is only interested in the + * validation result (returned rc). + * \param[in] str The string to convert. + * \param[in] base The integer base, i.e. 10 for decimal numbers or 16 for hexadecimal, as in strtoll(). + * \param[in] min_val The smallest valid number expected in the string. + * \param[in] max_val The largest valid number expected in the string. + * \return 0 on success, -EOVERFLOW if the number in the string exceeds int range, -ENOTSUPP if the base is not supported, + * -ERANGE if the converted number exceeds the range [min_val..max_val] but is still within int range, -E2BIG if + * surplus characters follow after the number, -EINVAL if the string does not contain a number. In case of -ERANGE and + * -E2BIG, the converted number is still accurately returned in result. In case of -EOVERFLOW, the returned value is + * clamped to INT_MIN..INT_MAX. + */ +int osmo_str_to_int(int *result, const char *str, int base, int min_val, int max_val) +{ + int64_t val; + int rc = osmo_str_to_int64(&val, str, base, min_val, max_val); + /* In case the number string exceeds long long int range, strtoll() clamps the returned value to LLONG_MIN or + * LLONG_MAX. Make sure of the same here with respect to int. */ + if (val < INT_MIN) { + if (result) + *result = INT_MIN; + return -EOVERFLOW; + } + if (val > INT_MAX) { + if (result) + *result = INT_MAX; + return -EOVERFLOW; + } + if (result) + *result = (int)val; + return rc; +} + +/*! Replace a string using talloc and release its prior content (if any). + * This is a format string capable equivalent of osmo_talloc_replace_string(). + * \param[in] ctx Talloc context to use for allocation. + * \param[out] dst Pointer to string, will be updated with ptr to new string. + * \param[in] fmt Format string that will be copied to newly allocated string. */ +void osmo_talloc_replace_string_fmt(void *ctx, char **dst, const char *fmt, ...) +{ + char *name = NULL; + + if (fmt != NULL) { + va_list ap; + + va_start(ap, fmt); + name = talloc_vasprintf(ctx, fmt, ap); + va_end(ap); + } + + talloc_free(*dst); + *dst = name; +} + +/*! @} */ |