/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
 */

#include <strings.h>
#include <stdlib.h>
#include <errno.h>
#include <ctype.h>

#include <dt_string.h>

/*
 * Transform string s inline, converting each embedded C escape sequence string
 * to the corresponding character.  For example, the substring "\n" is replaced
 * by an inline '\n' character.  The length of the resulting string is returned.
 */
size_t
stresc2chr(char *s)
{
        char *p, *q, c;
        int esc = 0;
        int x;

        for (p = q = s; (c = *p) != '\0'; p++) {
                if (esc) {
                        switch (c) {
                        case '0':
                        case '1':
                        case '2':
                        case '3':
                        case '4':
                        case '5':
                        case '6':
                        case '7':
                                c -= '0';
                                p++;

                                if (*p >= '0' && *p <= '7') {
                                        c = c * 8 + *p++ - '0';

                                        if (*p >= '0' && *p <= '7')
                                                c = c * 8 + *p - '0';
                                        else
                                                p--;
                                } else
                                        p--;

                                *q++ = c;
                                break;

                        case 'a':
                                *q++ = '\a';
                                break;
                        case 'b':
                                *q++ = '\b';
                                break;
                        case 'f':
                                *q++ = '\f';
                                break;
                        case 'n':
                                *q++ = '\n';
                                break;
                        case 'r':
                                *q++ = '\r';
                                break;
                        case 't':
                                *q++ = '\t';
                                break;
                        case 'v':
                                *q++ = '\v';
                                break;

                        case 'x':
                                for (x = 0; (c = *++p) != '\0'; ) {
                                        if (c >= '0' && c <= '9')
                                                x = x * 16 + c - '0';
                                        else if (c >= 'a' && c <= 'f')
                                                x = x * 16 + c - 'a' + 10;
                                        else if (c >= 'A' && c <= 'F')
                                                x = x * 16 + c - 'A' + 10;
                                        else
                                                break;
                                }
                                *q++ = (char)x;
                                p--;
                                break;

                        case '"':
                        case '\\':
                                *q++ = c;
                                break;
                        default:
                                *q++ = '\\';
                                *q++ = c;
                        }

                        esc = 0;

                } else {
                        if ((esc = c == '\\') == 0)
                                *q++ = c;
                }
        }

        *q = '\0';
        return ((size_t)(q - s));
}

/*
 * Create a copy of string s in which certain unprintable or special characters
 * have been converted to the string representation of their C escape sequence.
 * For example, the newline character is expanded to the string "\n".
 */
char *
strchr2esc(const char *s, size_t n)
{
        const char *p;
        char *q, *s2, c;
        size_t addl = 0;

        for (p = s; p < s + n; p++) {
                switch (c = *p) {
                case '\0':
                case '\a':
                case '\b':
                case '\f':
                case '\n':
                case '\r':
                case '\t':
                case '\v':
                case '"':
                case '\\':
                        addl++;         /* 1 add'l char needed to follow \ */
                        break;
                case ' ':
                        break;
                default:
                        if (c < '!' || c > '~')
                                addl += 3; /* 3 add'l chars following \ */
                }
        }

        if ((s2 = malloc(n + addl + 1)) == NULL)
                return (NULL);

        for (p = s, q = s2; p < s + n; p++) {
                switch (c = *p) {
                case '\0':
                        *q++ = '\\';
                        *q++ = '0';
                        break;
                case '\a':
                        *q++ = '\\';
                        *q++ = 'a';
                        break;
                case '\b':
                        *q++ = '\\';
                        *q++ = 'b';
                        break;
                case '\f':
                        *q++ = '\\';
                        *q++ = 'f';
                        break;
                case '\n':
                        *q++ = '\\';
                        *q++ = 'n';
                        break;
                case '\r':
                        *q++ = '\\';
                        *q++ = 'r';
                        break;
                case '\t':
                        *q++ = '\\';
                        *q++ = 't';
                        break;
                case '\v':
                        *q++ = '\\';
                        *q++ = 'v';
                        break;
                case '"':
                        *q++ = '\\';
                        *q++ = '"';
                        break;
                case '\\':
                        *q++ = '\\';
                        *q++ = '\\';
                        break;
                case ' ':
                        *q++ = c;
                        break;
                default:
                        if (c < '!' || c > '~') {
                                *q++ = '\\';
                                *q++ = ((c >> 6) & 3) + '0';
                                *q++ = ((c >> 3) & 7) + '0';
                                *q++ = (c & 7) + '0';
                        } else
                                *q++ = c;
                }

                if (c == '\0')
                        break; /* don't continue past \0 even if p < s + n */
        }

        *q = '\0';
        return (s2);
}

/*
 * Return the basename (name after final /) of the given string.  We use
 * strbasename rather than basename to avoid conflicting with libgen.h's
 * non-const function prototype.
 */
const char *
strbasename(const char *s)
{
        const char *p = strrchr(s, '/');

        if (p == NULL)
                return (s);

        return (++p);
}

/*
 * This function tests a string against the regular expression used for idents
 * and integers in the D lexer, and should match the superset of RGX_IDENT and
 * RGX_INT in dt_lex.l.  If an invalid character is found, the function returns
 * a pointer to it.  Otherwise NULL is returned for a valid string.
 */
const char *
strbadidnum(const char *s)
{
        char *p;
        int c;

        if (*s == '\0')
                return (s);

        errno = 0;
        (void) strtoull(s, &p, 0);

        if (errno == 0 && *p == '\0')
                return (NULL); /* matches RGX_INT */

        while ((c = *s++) != '\0') {
                if (isalnum(c) == 0 && c != '_' && c != '`')
                        return (s - 1);
        }

        return (NULL); /* matches RGX_IDENT */
}

/*
 * Determine whether the string contains a glob matching pattern or is just a
 * simple string.  See gmatch(3GEN) and sh(1) for the glob syntax definition.
 */
int
strisglob(const char *s)
{
        char c;

        while ((c = *s++) != '\0') {
                if (c == '[' || c == '?' || c == '*' || c == '\\')
                        return (1);
        }

        return (0);
}

/*
 * Hyphenate a string in-place by converting any instances of "__" to "-",
 * which we use for probe names to improve readability, and return the string.
 */
char *
strhyphenate(char *s)
{
        char *p, *q;

        for (p = s, q = p + strlen(p); p < q; p++) {
                if (p[0] == '_' && p[1] == '_') {
                        p[0] = '-';
                        bcopy(p + 2, p + 1, (size_t)(q - p) - 1);
                }
        }

        return (s);
}