blob: a43423528382d597c328441117179b6cd927ee10 [file] [log] [blame]
/**
* @file common.c
* @author Michal Vasko <mvasko@cesnet.cz>
* @brief common internal definitions for libyang
*
* Copyright (c) 2018 CESNET, z.s.p.o.
*
* This source code is licensed under BSD 3-Clause License (the "License").
* You may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://opensource.org/licenses/BSD-3-Clause
*/
#define _GNU_SOURCE
#include "common.h"
#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <inttypes.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <unistd.h>
#include "compat.h"
#include "tree_schema_internal.h"
void *
ly_realloc(void *ptr, size_t size)
{
void *new_mem;
new_mem = realloc(ptr, size);
if (!new_mem) {
free(ptr);
}
return new_mem;
}
char *
ly_strnchr(const char *s, int c, size_t len)
{
for ( ; len && (*s != (char)c); ++s, --len) {}
return len ? (char *)s : NULL;
}
int
ly_strncmp(const char *refstr, const char *str, size_t str_len)
{
int rc = strncmp(refstr, str, str_len);
if (!rc && (refstr[str_len] == '\0')) {
return 0;
} else {
return rc ? rc : 1;
}
}
#define LY_OVERFLOW_ADD(MAX, X, Y) ((X > MAX - Y) ? 1 : 0)
#define LY_OVERFLOW_MUL(MAX, X, Y) ((X > MAX / Y) ? 1 : 0)
LY_ERR
ly_strntou8(const char *nptr, size_t len, uint8_t *ret)
{
uint8_t num = 0, dig, dec_pow;
if (len > 3) {
/* overflow for sure */
return LY_EDENIED;
}
dec_pow = 1;
for ( ; len && isdigit(nptr[len - 1]); --len) {
dig = nptr[len - 1] - 48;
if (LY_OVERFLOW_MUL(UINT8_MAX, dig, dec_pow)) {
return LY_EDENIED;
}
dig *= dec_pow;
if (LY_OVERFLOW_ADD(UINT8_MAX, num, dig)) {
return LY_EDENIED;
}
num += dig;
dec_pow *= 10;
}
if (len) {
return LY_EVALID;
}
*ret = num;
return LY_SUCCESS;
}
uint32_t
ly_value_prefix_next(const char *str_begin, const char *str_end, ly_bool *is_prefix, const char **str_next)
{
const char *stop, *prefix;
size_t bytes;
uint32_t c;
ly_bool prefix_found;
uint32_t ret;
assert(is_prefix && str_next);
#define IS_AT_END(PTR, STR_END) (STR_END ? PTR == STR_END : !(*PTR))
*str_next = NULL;
*is_prefix = 0;
ret = 0;
if (!str_begin || !(*str_begin) || (str_begin == str_end)) {
return ret;
}
stop = str_begin;
prefix = NULL;
prefix_found = 0;
do {
/* look for the beginning of the YANG value */
for (ly_getutf8(&stop, &c, &bytes);
!is_xmlqnamestartchar(c) && !IS_AT_END(stop, str_end);
ly_getutf8(&stop, &c, &bytes)) {}
if (IS_AT_END(stop, str_end)) {
break;
}
/* maybe the prefix was found */
prefix = stop - bytes;
/* look for the the end of the prefix */
for (ly_getutf8(&stop, &c, &bytes);
is_xmlqnamechar(c) && !IS_AT_END(stop, str_end);
ly_getutf8(&stop, &c, &bytes)) {}
prefix_found = c == ':' ? 1 : 0;
/* if it wasn't the prefix, keep looking */
} while (!IS_AT_END(stop, str_end) && !prefix_found);
if ((str_begin == prefix) && prefix_found) {
/* prefix found at the beginning of the input string */
*is_prefix = 1;
*str_next = IS_AT_END(stop, str_end) ? NULL : stop;
ret = (stop - bytes) - str_begin;
} else if ((str_begin != prefix) && (prefix_found)) {
/* there is a some string before prefix */
*str_next = prefix;
ret = prefix - str_begin;
} else {
/* no prefix found */
ret = stop - str_begin;
}
#undef IS_AT_END
return ret;
}
LY_ERR
ly_getutf8(const char **input, uint32_t *utf8_char, size_t *bytes_read)
{
uint32_t c, aux;
size_t len;
if (bytes_read) {
(*bytes_read) = 0;
}
c = (*input)[0];
LY_CHECK_RET(!c, LY_EINVAL);
if (!(c & 0x80)) {
/* one byte character */
len = 1;
if ((c < 0x20) && (c != 0x9) && (c != 0xa) && (c != 0xd)) {
return LY_EINVAL;
}
} else if ((c & 0xe0) == 0xc0) {
/* two bytes character */
len = 2;
aux = (*input)[1];
if ((aux & 0xc0) != 0x80) {
return LY_EINVAL;
}
c = ((c & 0x1f) << 6) | (aux & 0x3f);
if (c < 0x80) {
return LY_EINVAL;
}
} else if ((c & 0xf0) == 0xe0) {
/* three bytes character */
len = 3;
c &= 0x0f;
for (uint64_t i = 1; i <= 2; i++) {
aux = (*input)[i];
if ((aux & 0xc0) != 0x80) {
return LY_EINVAL;
}
c = (c << 6) | (aux & 0x3f);
}
if ((c < 0x800) || ((c > 0xd7ff) && (c < 0xe000)) || (c > 0xfffd)) {
return LY_EINVAL;
}
} else if ((c & 0xf8) == 0xf0) {
/* four bytes character */
len = 4;
c &= 0x07;
for (uint64_t i = 1; i <= 3; i++) {
aux = (*input)[i];
if ((aux & 0xc0) != 0x80) {
return LY_EINVAL;
}
c = (c << 6) | (aux & 0x3f);
}
if ((c < 0x1000) || (c > 0x10ffff)) {
return LY_EINVAL;
}
} else {
return LY_EINVAL;
}
(*utf8_char) = c;
(*input) += len;
if (bytes_read) {
(*bytes_read) = len;
}
return LY_SUCCESS;
}
LY_ERR
ly_pututf8(char *dst, uint32_t value, size_t *bytes_written)
{
if (value < 0x80) {
/* one byte character */
if ((value < 0x20) &&
(value != 0x09) &&
(value != 0x0a) &&
(value != 0x0d)) {
return LY_EINVAL;
}
dst[0] = value;
(*bytes_written) = 1;
} else if (value < 0x800) {
/* two bytes character */
dst[0] = 0xc0 | (value >> 6);
dst[1] = 0x80 | (value & 0x3f);
(*bytes_written) = 2;
} else if (value < 0xfffe) {
/* three bytes character */
if (((value & 0xf800) == 0xd800) ||
((value >= 0xfdd0) && (value <= 0xfdef))) {
/* exclude surrogate blocks %xD800-DFFF */
/* exclude noncharacters %xFDD0-FDEF */
return LY_EINVAL;
}
dst[0] = 0xe0 | (value >> 12);
dst[1] = 0x80 | ((value >> 6) & 0x3f);
dst[2] = 0x80 | (value & 0x3f);
(*bytes_written) = 3;
} else if (value < 0x10fffe) {
if ((value & 0xffe) == 0xffe) {
/* exclude noncharacters %xFFFE-FFFF, %x1FFFE-1FFFF, %x2FFFE-2FFFF, %x3FFFE-3FFFF, %x4FFFE-4FFFF,
* %x5FFFE-5FFFF, %x6FFFE-6FFFF, %x7FFFE-7FFFF, %x8FFFE-8FFFF, %x9FFFE-9FFFF, %xAFFFE-AFFFF,
* %xBFFFE-BFFFF, %xCFFFE-CFFFF, %xDFFFE-DFFFF, %xEFFFE-EFFFF, %xFFFFE-FFFFF, %x10FFFE-10FFFF */
return LY_EINVAL;
}
/* four bytes character */
dst[0] = 0xf0 | (value >> 18);
dst[1] = 0x80 | ((value >> 12) & 0x3f);
dst[2] = 0x80 | ((value >> 6) & 0x3f);
dst[3] = 0x80 | (value & 0x3f);
(*bytes_written) = 4;
} else {
return LY_EINVAL;
}
return LY_SUCCESS;
}
/**
* @brief Static table of the UTF8 characters lengths according to their first byte.
*/
static const unsigned char utf8_char_length_table[] = {
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 1, 1
};
size_t
ly_utf8len(const char *str, size_t bytes)
{
size_t len = 0;
const char *ptr = str;
while (((size_t)(ptr - str) < bytes) && *ptr) {
++len;
ptr += utf8_char_length_table[((unsigned char)(*ptr))];
}
return len;
}
size_t
LY_VCODE_INSTREXP_len(const char *str)
{
size_t len = 0;
if (!str) {
return len;
} else if (!str[0]) {
return 1;
}
for (len = 1; len < LY_VCODE_INSTREXP_MAXLEN && str[len]; ++len) {}
return len;
}
LY_ERR
ly_mmap(struct ly_ctx *ctx, int fd, size_t *length, void **addr)
{
struct stat sb;
long pagesize;
size_t m;
assert(length);
assert(addr);
assert(fd >= 0);
if (fstat(fd, &sb) == -1) {
LOGERR(ctx, LY_ESYS, "Failed to stat the file descriptor (%s) for the mmap().", strerror(errno));
return LY_ESYS;
}
if (!S_ISREG(sb.st_mode)) {
LOGERR(ctx, LY_EINVAL, "File to mmap() is not a regular file.");
return LY_ESYS;
}
if (!sb.st_size) {
*addr = NULL;
return LY_SUCCESS;
}
pagesize = sysconf(_SC_PAGESIZE);
m = sb.st_size % pagesize;
if (m && (pagesize - m >= 1)) {
/* there will be enough space (at least 1 byte) after the file content mapping to provide zeroed NULL-termination byte */
*length = sb.st_size + 1;
*addr = mmap(NULL, *length, PROT_READ, MAP_PRIVATE, fd, 0);
} else {
/* there will not be enough bytes after the file content mapping for the additional bytes and some of them
* would overflow into another page that would not be zerroed and any access into it would generate SIGBUS.
* Therefore we have to do the following hack with double mapping. First, the required number of bytes
* (including the additinal bytes) is required as anonymous and thus they will be really provided (actually more
* because of using whole pages) and also initialized by zeros. Then, the file is mapped to the same address
* where the anonymous mapping starts. */
*length = sb.st_size + pagesize;
*addr = mmap(NULL, *length, PROT_READ, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
*addr = mmap(*addr, sb.st_size, PROT_READ, MAP_PRIVATE | MAP_FIXED, fd, 0);
}
if (*addr == MAP_FAILED) {
LOGERR(ctx, LY_ESYS, "mmap() failed (%s).", strerror(errno));
return LY_ESYS;
}
return LY_SUCCESS;
}
LY_ERR
ly_munmap(void *addr, size_t length)
{
if (munmap(addr, length)) {
return LY_ESYS;
}
return LY_SUCCESS;
}
LY_ERR
ly_strcat(char **dest, const char *format, ...)
{
va_list fp;
char *addition = NULL;
size_t len;
va_start(fp, format);
len = vasprintf(&addition, format, fp);
len += (*dest ? strlen(*dest) : 0) + 1;
if (*dest) {
*dest = ly_realloc(*dest, len);
if (!*dest) {
va_end(fp);
return LY_EMEM;
}
*dest = strcat(*dest, addition);
free(addition);
} else {
*dest = addition;
}
va_end(fp);
return LY_SUCCESS;
}
LY_ERR
ly_parse_int(const char *val_str, size_t val_len, int64_t min, int64_t max, int base, int64_t *ret)
{
LY_ERR rc = LY_SUCCESS;
char *ptr, *str;
int64_t i;
LY_CHECK_ARG_RET(NULL, val_str, val_str[0], val_len, LY_EINVAL);
/* duplicate the value */
str = strndup(val_str, val_len);
LY_CHECK_RET(!str, LY_EMEM);
/* parse the value to avoid accessing following bytes */
errno = 0;
i = strtoll(str, &ptr, base);
if (errno || (ptr == str)) {
/* invalid string */
rc = LY_EVALID;
} else if ((i < min) || (i > max)) {
/* invalid number */
rc = LY_EDENIED;
} else if (*ptr) {
while (isspace(*ptr)) {
++ptr;
}
if (*ptr) {
/* invalid characters after some number */
rc = LY_EVALID;
}
}
/* cleanup */
free(str);
if (!rc) {
*ret = i;
}
return rc;
}
LY_ERR
ly_parse_uint(const char *val_str, size_t val_len, uint64_t max, int base, uint64_t *ret)
{
LY_ERR rc = LY_SUCCESS;
char *ptr, *str;
uint64_t u;
LY_CHECK_ARG_RET(NULL, val_str, val_str[0], val_len, LY_EINVAL);
/* duplicate the value to avoid accessing following bytes */
str = strndup(val_str, val_len);
LY_CHECK_RET(!str, LY_EMEM);
/* parse the value */
errno = 0;
u = strtoull(str, &ptr, base);
if (errno || (ptr == str)) {
/* invalid string */
rc = LY_EVALID;
} else if ((u > max) || (u && (str[0] == '-'))) {
/* invalid number */
rc = LY_EDENIED;
} else if (*ptr) {
while (isspace(*ptr)) {
++ptr;
}
if (*ptr) {
/* invalid characters after some number */
rc = LY_EVALID;
}
}
/* cleanup */
free(str);
if (!rc) {
*ret = u;
}
return rc;
}
/**
* @brief Parse an identifier.
*
* ;; An identifier MUST NOT start with (('X'|'x') ('M'|'m') ('L'|'l'))
* identifier = (ALPHA / "_")
* *(ALPHA / DIGIT / "_" / "-" / ".")
*
* @param[in,out] id Identifier to parse. When returned, it points to the first character which is not part of the identifier.
* @return LY_ERR value: LY_SUCCESS or LY_EINVAL in case of invalid starting character.
*/
static LY_ERR
lys_parse_id(const char **id)
{
assert(id && *id);
if (!is_yangidentstartchar(**id)) {
return LY_EINVAL;
}
++(*id);
while (is_yangidentchar(**id)) {
++(*id);
}
return LY_SUCCESS;
}
LY_ERR
ly_parse_nodeid(const char **id, const char **prefix, size_t *prefix_len, const char **name, size_t *name_len)
{
assert(id && *id);
assert(prefix && prefix_len);
assert(name && name_len);
*prefix = *id;
*prefix_len = 0;
*name = NULL;
*name_len = 0;
LY_CHECK_RET(lys_parse_id(id));
if (**id == ':') {
/* there is prefix */
*prefix_len = *id - *prefix;
++(*id);
*name = *id;
LY_CHECK_RET(lys_parse_id(id));
*name_len = *id - *name;
} else {
/* there is no prefix, so what we have as prefix now is actually the name */
*name = *prefix;
*name_len = *id - *name;
*prefix = NULL;
}
return LY_SUCCESS;
}
LY_ERR
ly_parse_instance_predicate(const char **pred, size_t limit, LYD_FORMAT format,
const char **prefix, size_t *prefix_len, const char **id, size_t *id_len, const char **value, size_t *value_len,
const char **errmsg)
{
LY_ERR ret = LY_EVALID;
const char *in = *pred;
size_t offset = 1;
uint8_t expr = 0; /* 0 - position predicate; 1 - leaf-list-predicate; 2 - key-predicate */
char quot;
assert(in[0] == '[');
*prefix = *id = *value = NULL;
*prefix_len = *id_len = *value_len = 0;
/* leading *WSP */
for ( ; isspace(in[offset]); offset++) {}
if (isdigit(in[offset])) {
/* pos: "[" *WSP positive-integer-value *WSP "]" */
if (in[offset] == '0') {
/* zero */
*errmsg = "The position predicate cannot be zero.";
goto error;
}
/* positive-integer-value */
*value = &in[offset++];
for ( ; isdigit(in[offset]); offset++) {}
*value_len = &in[offset] - *value;
} else if (in[offset] == '.') {
/* leaf-list-predicate: "[" *WSP "." *WSP "=" *WSP quoted-string *WSP "]" */
*id = &in[offset];
*id_len = 1;
offset++;
expr = 1;
} else if (in[offset] == '-') {
/* typically negative value */
*errmsg = "Invalid instance predicate format (negative position or invalid node-identifier).";
goto error;
} else {
/* key-predicate: "[" *WSP node-identifier *WSP "=" *WSP quoted-string *WSP "]" */
in = &in[offset];
if (ly_parse_nodeid(&in, prefix, prefix_len, id, id_len)) {
*errmsg = "Invalid node-identifier.";
goto error;
}
if ((format == LYD_XML) && !(*prefix)) {
/* all node names MUST be qualified with explicit namespace prefix */
*errmsg = "Missing prefix of a node name.";
goto error;
}
offset = in - *pred;
in = *pred;
expr = 2;
}
if (expr) {
/* *WSP "=" *WSP quoted-string *WSP "]" */
for ( ; isspace(in[offset]); offset++) {}
if (in[offset] != '=') {
if (expr == 1) {
*errmsg = "Unexpected character instead of \'=\' in leaf-list-predicate.";
} else { /* 2 */
*errmsg = "Unexpected character instead of \'=\' in key-predicate.";
}
goto error;
}
offset++;
for ( ; isspace(in[offset]); offset++) {}
/* quoted-string */
quot = in[offset++];
if ((quot != '\'') && (quot != '\"')) {
*errmsg = "String value is not quoted.";
goto error;
}
*value = &in[offset];
for ( ; offset < limit && (in[offset] != quot || (offset && in[offset - 1] == '\\')); offset++) {}
if (in[offset] == quot) {
*value_len = &in[offset] - *value;
offset++;
} else {
*errmsg = "Value is not terminated quoted-string.";
goto error;
}
}
/* *WSP "]" */
for ( ; isspace(in[offset]); offset++) {}
if (in[offset] != ']') {
if (expr == 0) {
*errmsg = "Predicate (pos) is not terminated by \']\' character.";
} else if (expr == 1) {
*errmsg = "Predicate (leaf-list-predicate) is not terminated by \']\' character.";
} else { /* 2 */
*errmsg = "Predicate (key-predicate) is not terminated by \']\' character.";
}
goto error;
}
offset++;
if (offset <= limit) {
*pred = &in[offset];
return LY_SUCCESS;
}
/* we read after the limit */
*errmsg = "Predicate is incomplete.";
*prefix = *id = *value = NULL;
*prefix_len = *id_len = *value_len = 0;
offset = limit;
ret = LY_EINVAL;
error:
*pred = &in[offset];
return ret;
}