/*
 * 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 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */
/* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

/*
 * rpc_scan.c, Scanner for the RPC protocol compiler
 */

#include <sys/wait.h>
#include <stdio.h>
#include <ctype.h>
#include <string.h>
#include <strings.h>
#include "rpc_scan.h"
#include "rpc_parse.h"
#include "rpc_util.h"

#define startcomment(where)     (where[0] == '/' && where[1] == '*')
#define endcomment(where)       (where[-1] == '*' && where[0] == '/')

static int pushed = 0;  /* is a token pushed */
static token lasttok;   /* last token, if pushed */

static void unget_token(token *);
static void findstrconst(char **, char **);
static void findchrconst(char **, char **);
static void findconst(char **, char **);
static void findkind(char **, token *);
static int cppline(char *);
static int directive(char *);
static void printdirective(char *);
static void docppline(char *, int *, char **);

/*
 * scan expecting 1 given token
 */
void
scan(tok_kind expect, token *tokp)
{
        get_token(tokp);
        if (tokp->kind != expect)
                expected1(expect);
}

/*
 * scan expecting any of the 2 given tokens
 */
void
scan2(tok_kind expect1, tok_kind expect2, token *tokp)
{
        get_token(tokp);
        if (tokp->kind != expect1 && tokp->kind != expect2)
                expected2(expect1, expect2);
}

/*
 * scan expecting any of the 3 given token
 */
void
scan3(tok_kind expect1, tok_kind expect2, tok_kind expect3, token *tokp)
{
        get_token(tokp);
        if (tokp->kind != expect1 && tokp->kind != expect2 &&
            tokp->kind != expect3)
                expected3(expect1, expect2, expect3);
}

/*
 * scan expecting a constant, possibly symbolic
 */
void
scan_num(token *tokp)
{
        get_token(tokp);
        switch (tokp->kind) {
        case TOK_IDENT:
                break;
        default:
                error("constant or identifier expected");
        }
}

/*
 * Peek at the next token
 */
void
peek(token *tokp)
{
        get_token(tokp);
        unget_token(tokp);
}

/*
 * Peek at the next token and scan it if it matches what you expect
 */
int
peekscan(tok_kind expect, token *tokp)
{
        peek(tokp);
        if (tokp->kind == expect) {
                get_token(tokp);
                return (1);
        }
        return (0);
}

/*
 * Get the next token, printing out any directive that are encountered.
 */
void
get_token(token *tokp)
{
        int commenting;
        int stat = 0;

        if (pushed) {
                pushed = 0;
                *tokp = lasttok;
                return;
        }
        commenting = 0;
        for (;;) {
                if (*where == 0) {
                        for (;;) {
                                if (!fgets(curline, MAXLINESIZE, fin)) {
                                        tokp->kind = TOK_EOF;
                                        /*
                                         * now check if cpp returned
                                         * non NULL value
                                         */
                                        (void) waitpid(childpid, &stat,
                                            WUNTRACED);
                                        if (stat > 0) {
                                        /* Set return value from rpcgen */
                                                nonfatalerrors = stat >> 8;
                                        }
                                        *where = 0;
                                        return;
                                }
                                linenum++;
                                if (commenting) {
                                        break;
                                } else if (cppline(curline)) {
                                        docppline(curline, &linenum,
                                            &infilename);
                                } else if (directive(curline)) {
                                        printdirective(curline);
                                } else {
                                        break;
                                }
                        }
                        where = curline;
                } else if (isspace(*where)) {
                        while (isspace(*where)) {
                                where++;        /* eat */
                        }
                } else if (commenting) {
                        for (where++; *where; where++) {
                                if (endcomment(where)) {
                                        where++;
                                        commenting--;
                                        break;
                                }
                        }
                } else if (startcomment(where)) {
                        where += 2;
                        commenting++;
                } else {
                        break;
                }
        }

        /*
         * 'where' is not whitespace, comment or directive Must be a token!
         */
        switch (*where) {
        case ':':
                tokp->kind = TOK_COLON;
                where++;
                break;
        case ';':
                tokp->kind = TOK_SEMICOLON;
                where++;
                break;
        case ',':
                tokp->kind = TOK_COMMA;
                where++;
                break;
        case '=':
                tokp->kind = TOK_EQUAL;
                where++;
                break;
        case '*':
                tokp->kind = TOK_STAR;
                where++;
                break;
        case '[':
                tokp->kind = TOK_LBRACKET;
                where++;
                break;
        case ']':
                tokp->kind = TOK_RBRACKET;
                where++;
                break;
        case '{':
                tokp->kind = TOK_LBRACE;
                where++;
                break;
        case '}':
                tokp->kind = TOK_RBRACE;
                where++;
                break;
        case '(':
                tokp->kind = TOK_LPAREN;
                where++;
                break;
        case ')':
                tokp->kind = TOK_RPAREN;
                where++;
                break;
        case '<':
                tokp->kind = TOK_LANGLE;
                where++;
                break;
        case '>':
                tokp->kind = TOK_RANGLE;
                where++;
                break;

        case '"':
                tokp->kind = TOK_STRCONST;
                findstrconst(&where, &tokp->str);
                break;
        case '\'':
                tokp->kind = TOK_CHARCONST;
                findchrconst(&where, &tokp->str);
                break;

        case '-':
        case '0':
        case '1':
        case '2':
        case '3':
        case '4':
        case '5':
        case '6':
        case '7':
        case '8':
        case '9':
                tokp->kind = TOK_IDENT;
                findconst(&where, &tokp->str);
                break;

        default:
                if (!(isalpha(*where) || *where == '_')) {
                        char buf[100];
                        char *p;
                        size_t blen;

                        (void) snprintf(buf, sizeof (buf),
                            "illegal character in file: ");
                        blen = strlen(buf);
                        p = buf + blen;
                        if (isprint(*where)) {
                                (void) snprintf(p, sizeof (buf) - blen,
                                    "%c", *where);
                        } else {
                                (void) snprintf(p, sizeof (buf) - blen,
                                    "%d", *where);
                        }
                        error(buf);
                }
                findkind(&where, tokp);
                break;
        }
}

static void
unget_token(token *tokp)
{
        lasttok = *tokp;
        pushed = 1;
}

static void
findstrconst(char **str, char **val)
{
        char *p;
        int size;

        p = *str;
        do {
                p++;
        } while (*p && *p != '"');
        if (*p == 0) {
                error("unterminated string constant");
        }
        p++;
        size = p - *str;
        *val = malloc(size + 1);
        (void) strncpy(*val, *str, size);
        (*val)[size] = 0;
        *str = p;
}

static void
findchrconst(char **str, char **val)
{
        char *p;
        int size;

        p = *str;
        do {
                p++;
        } while (*p && *p != '\'');
        if (*p == 0)
                error("unterminated string constant");
        p++;
        size = p - *str;
        if (size != 3)
                error("empty char string");
        *val = malloc(size + 1);
        (void) strncpy(*val, *str, size);
        (*val)[size] = 0;
        *str = p;
}

static void
findconst(char **str, char **val)
{
        char *p;
        int size;

        p = *str;
        if (*p == '0' && *(p + 1) == 'x') {
                p++;
                do {
                        p++;
                } while (isxdigit(*p));
        } else {
                do {
                        p++;
                } while (isdigit(*p));
        }
        size = p - *str;
        *val = malloc(size + 1);
        (void) strncpy(*val, *str, size);
        (*val)[size] = 0;
        *str = p;
}

static token symbols[] = {
                        {TOK_CONST, "const"},
                        {TOK_UNION, "union"},
                        {TOK_SWITCH, "switch"},
                        {TOK_CASE, "case"},
                        {TOK_DEFAULT, "default"},
                        {TOK_STRUCT, "struct"},
                        {TOK_TYPEDEF, "typedef"},
                        {TOK_ENUM, "enum"},
                        {TOK_OPAQUE, "opaque"},
                        {TOK_BOOL, "bool"},
                        {TOK_VOID, "void"},
                        {TOK_ONEWAY, "oneway"},
                        {TOK_CHAR, "char"},
                        {TOK_INT, "int"},
                        {TOK_UNSIGNED, "unsigned"},
                        {TOK_SHORT, "short"},
                        {TOK_LONG, "long"},
                        {TOK_HYPER, "hyper"},
                        {TOK_FLOAT, "float"},
                        {TOK_DOUBLE, "double"},
                        {TOK_QUAD, "quadruple"},
                        {TOK_STRING, "string"},
                        {TOK_PROGRAM, "program"},
                        {TOK_VERSION, "version"},
                        {TOK_EOF, "??????"},
};

static void
findkind(char **mark, token *tokp)
{
        int len;
        token *s;
        char *str;

        str = *mark;
        for (s = symbols; s->kind != TOK_EOF; s++) {
                len = strlen(s->str);
                if (strncmp(str, s->str, len) == 0) {
                        if (!isalnum(str[len]) && str[len] != '_') {
                                tokp->kind = s->kind;
                                tokp->str = s->str;
                                *mark = str + len;
                                return;
                        }
                }
        }
        tokp->kind = TOK_IDENT;
        for (len = 0; isalnum(str[len]) || str[len] == '_'; len++)
                /* LOOP */;
        tokp->str = malloc(len + 1);
        (void) strncpy(tokp->str, str, len);
        tokp->str[len] = 0;
        *mark = str + len;
}

static int
cppline(char *line)
{
        return (line == curline && *line == '#');
}

static int
directive(char *line)
{
        return (line == curline && *line == '%');
}

static void
printdirective(char *line)
{
        f_print(fout, "%s", line + 1);
}

static void
docppline(char *line, int *lineno, char **fname)
{
        char *file;
        int num;
        char *p;

        line++;
        while (isspace(*line))
                line++;
        num = atoi(line);
        while (isdigit(*line))
                line++;
        while (isspace(*line))
                line++;
        if (*line != '"')
                error("preprocessor error");
        line++;
        p = file = malloc(strlen(line) + 1);
        while (*line && *line != '"')
                *p++ = *line++;
        if (*line == 0)
                error("preprocessor error");
        *p = 0;
        if (*file == 0)
                *fname = NULL;
        else
                *fname = file;
        *lineno = num - 1;
}