165 lines
4.5 KiB
C
165 lines
4.5 KiB
C
/** regex - regular expression functions related to POSIX regex lib. */
|
|
|
|
/* This file is part of flex. */
|
|
|
|
/* Redistribution and use in source and binary forms, with or without */
|
|
/* modification, are permitted provided that the following conditions */
|
|
/* are met: */
|
|
|
|
/* 1. Redistributions of source code must retain the above copyright */
|
|
/* notice, this list of conditions and the following disclaimer. */
|
|
/* 2. Redistributions in binary form must reproduce the above copyright */
|
|
/* notice, this list of conditions and the following disclaimer in the */
|
|
/* documentation and/or other materials provided with the distribution. */
|
|
|
|
/* Neither the name of the University nor the names of its contributors */
|
|
/* may be used to endorse or promote products derived from this software */
|
|
/* without specific prior written permission. */
|
|
|
|
/* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR */
|
|
/* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED */
|
|
/* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR */
|
|
/* PURPOSE. */
|
|
|
|
#include "flexdef.h"
|
|
|
|
|
|
static const char* REGEXP_LINEDIR = "^#line ([[:digit:]]+) \"(.*)\"";
|
|
static const char* REGEXP_BLANK_LINE = "^[[:space:]]*$";
|
|
|
|
regex_t regex_linedir; /**< matches line directives */
|
|
regex_t regex_blank_line; /**< matches blank lines */
|
|
|
|
|
|
/** Initialize the regular expressions.
|
|
* @return true upon success.
|
|
*/
|
|
bool flex_init_regex(void)
|
|
{
|
|
flex_regcomp(®ex_linedir, REGEXP_LINEDIR, REG_EXTENDED);
|
|
flex_regcomp(®ex_blank_line, REGEXP_BLANK_LINE, REG_EXTENDED);
|
|
|
|
return true;
|
|
}
|
|
|
|
/** Compiles a regular expression or dies trying.
|
|
* @param preg Same as for regcomp().
|
|
* @param regex Same as for regcomp().
|
|
* @param cflags Same as for regcomp().
|
|
*/
|
|
void flex_regcomp(regex_t *preg, const char *regex, int cflags)
|
|
{
|
|
int err;
|
|
|
|
memset (preg, 0, sizeof (regex_t));
|
|
|
|
if ((err = regcomp (preg, regex, cflags)) != 0) {
|
|
const int errbuf_sz = 200;
|
|
char * errbuf=0;
|
|
|
|
errbuf = (char*)flex_alloc(errbuf_sz *sizeof(char));
|
|
regerror (err, preg, errbuf, errbuf_sz);
|
|
snprintf (errbuf, errbuf_sz, "regcomp failed: %s\n", errbuf);
|
|
|
|
flexfatal (errbuf);
|
|
free(errbuf);
|
|
}
|
|
}
|
|
|
|
/** Extract a copy of the match, or NULL if no match.
|
|
* @param m A match as returned by regexec().
|
|
* @param src The source string that was passed to regexec().
|
|
* @return The allocated string.
|
|
*/
|
|
char *regmatch_dup (regmatch_t * m, const char *src)
|
|
{
|
|
char *str;
|
|
int len;
|
|
|
|
if (m == NULL || m->rm_so < 0)
|
|
return NULL;
|
|
len = m->rm_eo - m->rm_so;
|
|
str = (char *) flex_alloc ((len + 1) * sizeof (char));
|
|
strncpy (str, src + m->rm_so, len);
|
|
str[len] = 0;
|
|
return str;
|
|
}
|
|
|
|
/** Copy the match.
|
|
* @param m A match as returned by regexec().
|
|
* @param dest The destination buffer.
|
|
* @param src The source string that was passed to regexec().
|
|
* @return dest
|
|
*/
|
|
char *regmatch_cpy (regmatch_t * m, char *dest, const char *src)
|
|
{
|
|
if (m == NULL || m->rm_so < 0) {
|
|
if (dest)
|
|
dest[0] = '\0';
|
|
return dest;
|
|
}
|
|
|
|
snprintf (dest, regmatch_len(m), "%s", src + m->rm_so);
|
|
return dest;
|
|
}
|
|
|
|
/** Get the length in characters of the match.
|
|
* @param m A match as returned by regexec().
|
|
* @param src The source string that was passed to regexec().
|
|
* @return The length of the match.
|
|
*/
|
|
int regmatch_len (regmatch_t * m)
|
|
{
|
|
if (m == NULL || m->rm_so < 0) {
|
|
return 0;
|
|
}
|
|
|
|
return m->rm_eo - m->rm_so;
|
|
}
|
|
|
|
|
|
|
|
/** Convert a regmatch_t object to an integer using the strtol() function.
|
|
* @param m A match as returned by regexec().
|
|
* @param src The source string that was passed to regexec().
|
|
* @param endptr Same as the second argument to strtol().
|
|
* @param base Same as the third argument to strtol().
|
|
* @return The converted integer or error (Return value is the same as for strtol()).
|
|
*/
|
|
int regmatch_strtol (regmatch_t * m, const char *src, char **endptr,
|
|
int base)
|
|
{
|
|
int n = 0;
|
|
|
|
#define bufsz 20
|
|
char buf[bufsz];
|
|
char *s;
|
|
|
|
if (m == NULL || m->rm_so < 0)
|
|
return 0;
|
|
|
|
if (regmatch_len (m) < bufsz)
|
|
s = regmatch_cpy (m, buf, src);
|
|
else
|
|
s = regmatch_dup (m, src);
|
|
|
|
n = strtol (s, endptr, base);
|
|
|
|
if (s != buf)
|
|
free (s);
|
|
|
|
return n;
|
|
}
|
|
|
|
/** Check for empty or non-existent match.
|
|
* @param m A match as returned by regexec().
|
|
* @return false if match length is non-zero.
|
|
* Note that reg_empty returns true even if match did not occur at all.
|
|
*/
|
|
bool regmatch_empty (regmatch_t * m)
|
|
{
|
|
return (m == NULL || m->rm_so < 0 || m->rm_so == m->rm_eo);
|
|
}
|
|
|
|
/* vim:set expandtab cindent tabstop=4 softtabstop=4 shiftwidth=4 textwidth=0: */
|