/*
* Copyright © 2012 Ran Benita <ran234@gmail.com>
* SPDX-License-Identifier: MIT
*/
#pragma once
#include "config.h"
#include <stdbool.h>
#include <stddef.h>
#include <string.h>
#include "context.h"
#include "darray.h"
#include "messages-codes.h"
#include "utils.h"
/* Point to some substring in the file; used to avoid copying. */
struct sval {
const char *start;
unsigned int len;
};
typedef darray(struct sval) darray_sval;
static inline bool
svaleq(struct sval s1, struct sval s2)
{
return s1.len == s2.len && memcmp(s1.start, s2.start, s1.len) == 0;
}
static inline bool
isvaleq(struct sval s1, struct sval s2)
{
return s1.len == s2.len && istrncmp(s1.start, s2.start, s1.len) == 0;
}
static inline bool
svaleq_prefix(struct sval s1, struct sval s2)
{
return s1.len <= s2.len && memcmp(s1.start, s2.start, s1.len) == 0;
}
#define SVAL(start, len) (struct sval){(start), len}
#define SVAL_LIT(literal) SVAL(literal, sizeof(literal) - 1)
#define SVAL_INIT(literal) { literal, sizeof(literal) - 1 }
/* A line:column location in the input string (1-based). */
struct scanner_loc {
size_t line, column;
};
struct scanner {
const char *s;
size_t pos;
size_t len;
char buf[1024];
size_t buf_pos;
/* The position of the start of the current token. */
size_t token_pos;
/* Cached values used by scanner_token_location. */
size_t cached_pos;
struct scanner_loc cached_loc;
const char *file_name;
struct xkb_context *ctx;
void *priv;
};
/* Compute the line:column location for the current token (slow). */
struct scanner_loc
scanner_token_location(struct scanner *s);
#define scanner_log_with_code(scanner, level, verbosity, log_msg_id, fmt, ...) do { \
struct scanner_loc loc = scanner_token_location((scanner)); \
xkb_log_with_code((scanner)->ctx, (level), verbosity, log_msg_id, \
"%s:%zu:%zu: " fmt "\n", \
(scanner)->file_name, \
loc.line, \
loc.column, ##__VA_ARGS__); \
} while(0)
#define scanner_err(scanner, id, fmt, ...) \
scanner_log_with_code(scanner, XKB_LOG_LEVEL_ERROR, 0, id, \
fmt, ##__VA_ARGS__)
#define scanner_warn(scanner, id, fmt, ...) \
scanner_log_with_code(scanner, XKB_LOG_LEVEL_WARNING, 0, id, \
fmt, ##__VA_ARGS__)
#define scanner_vrb(scanner, verbosity, id, fmt, ...) \
scanner_log_with_code(scanner, XKB_LOG_LEVEL_WARNING, verbosity, id, \
fmt, ##__VA_ARGS__)
static inline void
scanner_init(struct scanner *s, struct xkb_context *ctx,
const char *string, size_t len, const char *file_name,
void *priv)
{
s->s = string;
s->len = len;
s->pos = 0;
s->token_pos = 0;
s->cached_pos = 0;
s->cached_loc.line = s->cached_loc.column = 1;
s->file_name = file_name;
s->ctx = ctx;
s->priv = priv;
}
static inline char
scanner_peek(struct scanner *s)
{
if (unlikely(s->pos >= s->len))
return '\0';
return s->s[s->pos];
}
static inline bool
scanner_eof(struct scanner *s)
{
return s->pos >= s->len;
}
static inline bool
scanner_eol(struct scanner *s)
{
return scanner_peek(s) == '\n';
}
static inline void
scanner_skip_to_eol(struct scanner *s)
{
const char *nl = memchr(s->s + s->pos, '\n', s->len - s->pos);
const size_t new_pos = nl ? (size_t) (nl - s->s) : s->len;
s->pos = new_pos;
}
static inline char
scanner_next(struct scanner *s)
{
if (unlikely(scanner_eof(s)))
return '\0';
return s->s[s->pos++];
}
static inline bool
scanner_chr(struct scanner *s, char ch)
{
if (likely(scanner_peek(s) != ch))
return false;
s->pos++;
return true;
}
static inline bool
scanner_str(struct scanner *s, const char *string, size_t len)
{
if (s->len - s->pos < len)
return false;
if (memcmp(s->s + s->pos, string, len) != 0)
return false;
s->pos += len;
return true;
}
#define scanner_lit(s, literal) scanner_str(s, literal, sizeof(literal) - 1)
static inline bool
scanner_buf_append(struct scanner *s, char ch)
{
if (s->buf_pos + 1 >= sizeof(s->buf))
return false;
s->buf[s->buf_pos++] = ch;
return true;
}
static inline bool
scanner_buf_appends(struct scanner *s, const char *str)
{
int ret;
ret = snprintf(s->buf + s->buf_pos, sizeof(s->buf) - s->buf_pos, "%s", str);
if (ret < 0 || (size_t) ret >= sizeof(s->buf) - s->buf_pos)
return false;
s->buf_pos += ret;
return true;
}
static inline bool
scanner_oct(struct scanner *s, uint8_t *out)
{
int i;
for (i = 0, *out = 0; scanner_peek(s) >= '0' && scanner_peek(s) <= '7' && i < 3; i++)
/* Test overflow */
if (*out < 040) {
*out = *out * 8 + scanner_next(s) - '0';
} else {
/* Consume valid digit, but mark result as invalid */
scanner_next(s);
return false;
}
return i > 0;
}
static inline bool
scanner_hex(struct scanner *s, uint8_t *out)
{
int i;
for (i = 0, *out = 0; is_xdigit(scanner_peek(s)) && i < 2; i++) {
const char c = scanner_next(s);
const char offset = (char) (c >= '0' && c <= '9' ? '0' :
c >= 'a' && c <= 'f' ? 'a' - 10
: 'A' - 10);
*out = *out * 16 + c - offset;
}
return i > 0;
}
/* Basic detection of wrong character encoding based on the first bytes */
static inline bool
scanner_check_supported_char_encoding(struct scanner *scanner)
{
/* Skip UTF-8 encoded BOM (U+FEFF)
* See: https://www.unicode.org/faq/utf_bom.html#bom5 */
if (scanner_str(scanner, "\xef\xbb\xbf", 3) || scanner->len < 2) {
/* Assume UTF-8 encoding or trivial short input */
return true;
}
/* Early detection of wrong file encoding, e.g. UTF-16 or UTF-32 */
if (scanner->s[0] == '\0' || scanner->s[1] == '\0') {
scanner_err(scanner, XKB_LOG_MESSAGE_NO_ID,
"unexpected NULL character.");
return false;
}
/* Enforce the first character to be ASCII.
See the note before the use of this function, that explains the relevant
parts of the grammars of rules, keymap components and Compose. */
if (!is_ascii(scanner->s[0])) {
scanner_err(scanner, XKB_LOG_MESSAGE_NO_ID,
"unexpected non-ASCII character.");
return false;
}
return true;
}
