/*
 * $Id: cf_gen.cc,v 1.62 2007/09/17 20:21:23 hno Exp $
 *
 * DEBUG: none          Generate squid.conf.default and cf_parser.h
 * AUTHOR: Max Okumoto
 *
 * SQUID Web Proxy Cache          http://www.squid-cache.org/
 * ----------------------------------------------------------
 *
 *  Squid is the result of efforts by numerous individuals from
 *  the Internet community; see the CONTRIBUTORS file for full
 *  details.   Many organizations have provided support for Squid's
 *  development; see the SPONSORS file for full details.  Squid is
 *  Copyrighted (C) 2001 by the Regents of the University of
 *  California; see the COPYRIGHT file for full details.  Squid
 *  incorporates software developed and/or copyrighted by other
 *  sources; see the CREDITS file for full details.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *  
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *  
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
 *
 */

/*****************************************************************************
 * Abstract:	This program parses the input file and generates code and
 *		files used to configure the variables in squid.
 *		(ie it creates the squid.conf.default file from the cf.data file)
 *
 *		The output files are as follows:
 *		cf_parser.h - this file contains, default_all() which
 *			  initializes variables with the default
 *			  values, parse_line() that parses line from
 *			  squid.conf.default, dump_config that dumps the
 *			  current the values of the variables.
 *		squid.conf.default - default configuration file given to the server
 *			 administrator.
 *****************************************************************************/

#include "squid.h"
#include "SquidTime.h"
#include "cf_gen_defines.h"

#define MAX_LINE	1024	/* longest configuration line */
#define _PATH_PARSER		"cf_parser.h"
#define _PATH_SQUID_CONF	"squid.conf.default"
#define _PATH_CF_DEPEND		"cf.data.depend"

enum State {
    sSTART,
    s1,
    sDOC,
    sNOCOMMENT,
    sEXIT
};

typedef struct Line
{
    char *data;

    struct Line *next;
}

Line;

typedef struct EntryAlias
{

    struct EntryAlias *next;
    char *name;
}

EntryAlias;

typedef struct Entry
{
    char *name;
    EntryAlias *alias;
    char *type;
    char *loc;
    char *default_value;
    Line *default_if_none;
    char *comment;
    char *ifdef;
    Line *doc;
    Line *nocomment;
    int array_flag;

    struct Entry *next;
}

Entry;

typedef struct TypeDep
{
    char *name;

    TypeDep *next;
} TypeDep;

typedef struct Type
{
    char *name;
    TypeDep *depend;

    struct Type *next;
} Type;

static const char WS[] = " \t\n";
static int gen_default(Entry *, FILE *);
static void gen_parse(Entry *, FILE *);
static void gen_parse_entry(Entry *entry, FILE *fp);
static void gen_parse_alias(char *, EntryAlias *, Entry *, FILE *);
static void gen_dump(Entry *, FILE *);
static void gen_free(Entry *, FILE *);
static void gen_conf(Entry *, FILE *);
static void gen_default_if_none(Entry *, FILE *);


static void
lineAdd(Line ** L, const char *str)
{
    while (*L)
        L = &(*L)->next;

    *L = (Line *)xcalloc(1, sizeof(Line));

    (*L)->data = xstrdup(str);
}

static void
checkDepend(const char *directive, const char *name, const Type *types, const Entry *entries)
{
    const Type *type;
    for (type = types; type; type = type->next) {
	const TypeDep *dep;
	if (strcmp(type->name, name) != 0)
	    continue;
	for (dep = type->depend; dep; dep = dep->next) {
	    const Entry *entry;
	    for (entry = entries; entry; entry = entry->next) {
		if (strcmp(entry->name, dep->name) == 0)
		    break;
	    }
	    if (!entry) {
		fprintf(stderr, "ERROR: '%s' (%s) depends on '%s'\n", directive, name, dep->name);
		exit(1);
	    }
	}
	return;
    }
    fprintf(stderr, "ERROR: Dependencies for cf.data type '%s' used in '%s' not defined\n", name, directive);
    exit(1);
}

int
main(int argc, char *argv[])
{
    FILE *fp;
    char *input_filename = argv[1];
    const char *output_filename = _PATH_PARSER;
    const char *conf_filename = _PATH_SQUID_CONF;
    const char *type_depend = argv[2];
    int linenum = 0;
    Entry *entries = NULL;
    Entry *curr = NULL;
    Type *types = NULL;
    enum State state;
    int rc = 0;
    char *ptr = NULL;
#ifdef _SQUID_OS2_

    const char *rmode = "rt";
#else

    const char *rmode = "r";
#endif
    char buff[MAX_LINE];


    /*-------------------------------------------------------------------*
     * Parse type dependencies
     *-------------------------------------------------------------------*/
    if ((fp = fopen(type_depend, rmode)) == NULL) {
        perror(input_filename);
        exit(1);
    }

    while ((NULL != fgets(buff, MAX_LINE, fp))) {
	const char *type = strtok(buff, WS);
	const char *dep;
	if (!type || type[0] == '#')
	    continue;
	Type *t = (Type *)xcalloc(1, sizeof(*t));
	t->name = xstrdup(type);
	while ((dep = strtok(NULL, WS)) != NULL) {
	    TypeDep *d = (TypeDep *)xcalloc(1, sizeof(*d));
	    d->name = xstrdup(dep);
	    d->next = t->depend;
	    t->depend = d;
	}
	t->next = types;
	types = t;
    }
    fclose(fp);

    /*-------------------------------------------------------------------*
     * Parse input file
     *-------------------------------------------------------------------*/

    /* Open input file */

    if ((fp = fopen(input_filename, rmode)) == NULL) {
        perror(input_filename);
        exit(1);
    }

#ifdef _SQUID_WIN32_
    setmode(fileno(fp), O_TEXT);

#endif

    state = sSTART;

    while (feof(fp) == 0 && state != sEXIT) {
        char *t;

        if (NULL == fgets(buff, MAX_LINE, fp))
            break;

        linenum++;

        if ((t = strchr(buff, '\n')))
            *t = '\0';

        switch (state) {

        case sSTART:

            if ((strlen(buff) == 0) || (!strncmp(buff, "#", 1))) {
                /* ignore empty and comment lines */
                (void) 0;
            } else if (!strncmp(buff, "NAME:", 5)) {
                char *name, *aliasname;

                if ((name = strtok(buff + 5, WS)) == NULL) {
                    printf("Error in input file\n");
                    exit(1);
                }

                curr = (Entry *)xcalloc(1, sizeof(Entry));
                curr->name = xstrdup(name);

                while ((aliasname = strtok(NULL, WS)) != NULL) {
                    EntryAlias *alias = (EntryAlias *)xcalloc(1, sizeof(EntryAlias));
                    alias->next = curr->alias;
                    alias->name = xstrdup(aliasname);
                    curr->alias = alias;
                }

                state = s1;
            } else if (!strcmp(buff, "EOF")) {
                state = sEXIT;
            } else if (!strcmp(buff, "COMMENT_START")) {
                curr = (Entry *)xcalloc(1, sizeof(Entry));
                curr->name = xstrdup("comment");
                curr->loc = xstrdup("none");
                state = sDOC;
            } else {
                printf("Error on line %d\n", linenum);
                printf("--> %s\n", buff);
                exit(1);
            }

            break;

        case s1:

            if ((strlen(buff) == 0) || (!strncmp(buff, "#", 1))) {
                /* ignore empty and comment lines */
                (void) 0;
            } else if (!strncmp(buff, "COMMENT:", 8)) {
                ptr = buff + 8;

                while (xisspace(*ptr))
                    ptr++;

                curr->comment = xstrdup(ptr);
            } else if (!strncmp(buff, "DEFAULT:", 8)) {
                ptr = buff + 8;

                while (xisspace(*ptr))
                    ptr++;

                curr->default_value = xstrdup(ptr);
            } else if (!strncmp(buff, "DEFAULT_IF_NONE:", 16)) {
                ptr = buff + 16;

                while (xisspace(*ptr))
                    ptr++;

                lineAdd(&curr->default_if_none, ptr);
            } else if (!strncmp(buff, "LOC:", 4)) {
                if ((ptr = strtok(buff + 4, WS)) == NULL) {
                    printf("Error on line %d\n", linenum);
                    exit(1);
                }

                curr->loc = xstrdup(ptr);
            } else if (!strncmp(buff, "TYPE:", 5)) {
                if ((ptr = strtok(buff + 5, WS)) == NULL) {
                    printf("Error on line %d\n", linenum);
                    exit(1);
                }

                /* hack to support arrays, rather than pointers */
                if (0 == strcmp(ptr + strlen(ptr) - 2, "[]")) {
                    curr->array_flag = 1;
                    *(ptr + strlen(ptr) - 2) = '\0';
                }

		checkDepend(curr->name, ptr, types, entries);
                curr->type = xstrdup(ptr);
            } else if (!strncmp(buff, "IFDEF:", 6)) {
                if ((ptr = strtok(buff + 6, WS)) == NULL) {
                    printf("Error on line %d\n", linenum);
                    exit(1);
                }

                curr->ifdef = xstrdup(ptr);
            } else if (!strcmp(buff, "DOC_START")) {
                state = sDOC;
            } else if (!strcmp(buff, "DOC_NONE")) {
                /* add to list of entries */
                curr->next = entries;
                entries = curr;
                state = sSTART;
            } else {
                printf("Error on line %d\n", linenum);
                exit(1);
            }

            break;

        case sDOC:

            if (!strcmp(buff, "DOC_END") || !strcmp(buff, "COMMENT_END")) {
                Line *head = NULL;
                Line *line = curr->doc;
                /* reverse order of doc lines */

                while (line != NULL) {
                    Line *tmp;
                    tmp = line->next;
                    line->next = head;
                    head = line;
                    line = tmp;
                }

                curr->doc = head;
                /* add to list of entries */
                curr->next = entries;
                entries = curr;
                state = sSTART;
            } else if (!strcmp(buff, "NOCOMMENT_START")) {
                state = sNOCOMMENT;
            } else {
                Line *line = (Line *)xcalloc(1, sizeof(Line));
                line->data = xstrdup(buff);
                line->next = curr->doc;
                curr->doc = line;
            }

            break;

        case sNOCOMMENT:

            if (!strcmp(buff, "NOCOMMENT_END")) {
                Line *head = NULL;
                Line *line = curr->nocomment;
                /* reverse order of lines */

                while (line != NULL) {
                    Line *tmp;
                    tmp = line->next;
                    line->next = head;
                    head = line;
                    line = tmp;
                }

                curr->nocomment = head;
                state = sDOC;
            } else {
                Line *line = (Line *)xcalloc(1, sizeof(Line));
                line->data = xstrdup(buff);
                line->next = curr->nocomment;
                curr->nocomment = line;
            }

            break;

        case sEXIT:
            assert(0);		/* should never get here */
            break;
        }
    }

    if (state != sEXIT) {
        printf("Error unexpected EOF\n");
        exit(1);
    } else {
        /* reverse order of entries */
        Entry *head = NULL;

        while (entries != NULL) {
            Entry *tmp;

            tmp = entries->next;
            entries->next = head;
            head = entries;
            entries = tmp;
        }

        entries = head;
    }

    fclose(fp);

    /*-------------------------------------------------------------------*
     * Generate default_all()
     * Generate parse_line()
     * Generate dump_config()
     * Generate free_all()
     * Generate example squid.conf.default file
     *-------------------------------------------------------------------*/

    /* Open output x.c file */

    if ((fp = fopen(output_filename, "w")) == NULL) {
        perror(output_filename);
        exit(1);
    }

#ifdef _SQUID_WIN32_
    setmode(fileno(fp), O_TEXT);

#endif

    fprintf(fp,
            "/*\n"
            " * Generated automatically from %s by %s\n"
            " *\n"
            " * Abstract: This file contains routines used to configure the\n"
            " *           variables in the squid server.\n"
            " */\n"
            "\n",
            input_filename, argv[0]
           );

    rc = gen_default(entries, fp);

    gen_default_if_none(entries, fp);

    gen_parse(entries, fp);

    gen_dump(entries, fp);

    gen_free(entries, fp);

    fclose(fp);

    /* Open output x.conf file */
    if ((fp = fopen(conf_filename, "w")) == NULL) {
        perror(conf_filename);
        exit(1);
    }

#ifdef _SQUID_WIN32_
    setmode(fileno(fp), O_TEXT);

#endif

    gen_conf(entries, fp);

    fclose(fp);

    return (rc);
}

static int
gen_default(Entry * head, FILE * fp)
{
    Entry *entry;
    int rc = 0;
    fprintf(fp,
            "static void\n"
            "default_line(const char *s)\n"
            "{\n"
            "\tLOCAL_ARRAY(char, tmp_line, BUFSIZ);\n"
            "\txstrncpy(tmp_line, s, BUFSIZ);\n"
            "\txstrncpy(config_input_line, s, BUFSIZ);\n"
            "\tconfig_lineno++;\n"
            "\tparse_line(tmp_line);\n"
            "}\n"
           );
    fprintf(fp,
            "static void\n"
            "default_all(void)\n"
            "{\n"
            "\tcfg_filename = \"Default Configuration\";\n"
            "\tconfig_lineno = 0;\n"
           );

    for (entry = head; entry != NULL; entry = entry->next) {
        assert(entry->name);
        assert(entry != entry->next);

        if (!strcmp(entry->name, "comment"))
            continue;

        if (entry->loc == NULL) {
            fprintf(stderr, "NO LOCATION FOR %s\n", entry->name);
            rc |= 1;
            continue;
        }

        if (entry->default_value == NULL) {
            fprintf(stderr, "NO DEFAULT FOR %s\n", entry->name);
            rc |= 1;
            continue;
        }

        assert(entry->default_value);

        if (entry->ifdef)
            fprintf(fp, "#if %s\n", entry->ifdef);

        if (strcmp(entry->default_value, "none") == 0) {
            fprintf(fp, "\t/* No default for %s */\n", entry->name);
        } else {
            fprintf(fp, "\tdefault_line(\"%s %s\");\n",
                    entry->name,
                    entry->default_value);
        }

        if (entry->ifdef)
            fprintf(fp, "#endif\n");
    }

    fprintf(fp, "\tcfg_filename = NULL;\n");
    fprintf(fp, "}\n\n");
    return rc;
}

static void
gen_default_if_none(Entry * head, FILE * fp)
{
    Entry *entry;
    Line *line;
    fprintf(fp,
            "static void\n"
            "defaults_if_none(void)\n"
            "{\n"
           );

    for (entry = head; entry != NULL; entry = entry->next) {
        assert(entry->name);
        assert(entry->loc);

        if (entry->default_if_none == NULL)
            continue;

        if (entry->ifdef)
            fprintf(fp, "#if %s\n", entry->ifdef);

        if (entry->default_if_none) {
            fprintf(fp,
                    "\tif (check_null_%s(%s)) {\n",
                    entry->type,
                    entry->loc);

            for (line = entry->default_if_none; line; line = line->next)
                fprintf(fp,
                        "\t\tdefault_line(\"%s %s\");\n",
                        entry->name,
                        line->data);

            fprintf(fp, "\t}\n");
        }

        if (entry->ifdef)
            fprintf(fp, "#endif\n");
    }

    fprintf(fp, "}\n\n");
}

void
gen_parse_alias(char *name, EntryAlias *alias, Entry *entry, FILE *fp)
{
    fprintf(fp, "\tif (!strcmp(token, \"%s\")) {\n", name);

    if (strcmp(entry->loc, "none") == 0) {
        fprintf(fp,
                "\t\tparse_%s();\n",
                entry->type
               );
    } else {
        fprintf(fp,
                "\t\tparse_%s(&%s%s);\n",
                entry->type, entry->loc,
                entry->array_flag ? "[0]" : ""
               );
    }

    fprintf(fp,"\t\treturn 1;\n");
    fprintf(fp,"\t};\n");
}

void
gen_parse_entry(Entry *entry, FILE *fp)
{
    if (strcmp(entry->name, "comment") == 0)
        return;

    if (entry->ifdef)
        fprintf(fp, "#if %s\n", entry->ifdef);

    char *name = entry->name;

    EntryAlias *alias = entry->alias;

    assert (entry->loc);

    bool more;

    do {
        gen_parse_alias (name, alias,entry, fp);
        more = false;

        if (alias) {
            name = alias->name;
            alias = alias->next;
            more = true;
        }
    } while (more);

    if (entry->ifdef)
        fprintf(fp, "#endif\n");
}

static void
gen_parse(Entry * head, FILE * fp)
{
    fprintf(fp,
            "static int\n"
            "parse_line(char *buff)\n"
            "{\n"
            "\tchar\t*token;\n"
            "\tdebugs(0, 10, \"parse_line: \" << buff << \"\\n\" );\n"
            "\tif ((token = strtok(buff, w_space)) == NULL) \n"
            "\t\treturn 1;\t/* ignore empty lines */\n"
           );

    for (Entry *entry = head; entry != NULL; entry = entry->next)
        gen_parse_entry (entry, fp);

    fprintf(fp,
            "\treturn 0; /* failure */\n"
            "}\n\n"
           );
}

static void
gen_dump(Entry * head, FILE * fp)
{
    Entry *entry;
    fprintf(fp,
            "static void\n"
            "dump_config(StoreEntry *entry)\n"
            "{\n"
           );

    for (entry = head; entry != NULL; entry = entry->next) {
        assert(entry->loc);

        if (strcmp(entry->loc, "none") == 0)
            continue;

        if (strcmp(entry->name, "comment") == 0)
            continue;

        if (entry->ifdef)
            fprintf(fp, "#if %s\n", entry->ifdef);

        fprintf(fp, "\tdump_%s(entry, \"%s\", %s);\n",
                entry->type,
                entry->name,
                entry->loc);

        if (entry->ifdef)
            fprintf(fp, "#endif\n");
    }

    fprintf(fp, "}\n\n");
}

static void
gen_free(Entry * head, FILE * fp)
{
    Entry *entry;
    fprintf(fp,
            "static void\n"
            "free_all(void)\n"
            "{\n"
           );

    for (entry = head; entry != NULL; entry = entry->next) {
        assert(entry->loc);

        if (strcmp(entry->loc, "none") == 0)
            continue;

        if (strcmp(entry->name, "comment") == 0)
            continue;

        if (entry->ifdef)
            fprintf(fp, "#if %s\n", entry->ifdef);

        fprintf(fp, "\tfree_%s(&%s%s);\n",
                entry->type, entry->loc,
                entry->array_flag ? "[0]" : "");

        if (entry->ifdef)
            fprintf(fp, "#endif\n");
    }

    fprintf(fp, "}\n\n");
}

static int
defined(char *name)
{
    int i = 0;

    if (!name)
        return 1;

    for (i = 0; strcmp(defines[i].name, name) != 0; i++) {
        assert(defines[i].name);
    }

    return defines[i].defined;
}

static const char *
available_if(char *name)
{
    int i = 0;
    assert(name);

    for (i = 0; strcmp(defines[i].name, name) != 0; i++) {
        assert(defines[i].name);
    }

    return defines[i].enable;
}

static void
gen_conf(Entry * head, FILE * fp)
{
    Entry *entry;
    char buf[8192];
    Line *def = NULL;

    for (entry = head; entry != NULL; entry = entry->next) {
        Line *line;
        int blank = 1;
	int enabled = 1;

        if (!strcmp(entry->name, "comment"))
            (void) 0;
        else
            fprintf(fp, "#  TAG: %s", entry->name);

        if (entry->comment)
            fprintf(fp, "\t%s", entry->comment);

        fprintf(fp, "\n");

        if (!defined(entry->ifdef)) {
            fprintf(fp, "# Note: This option is only available if Squid is rebuilt with the\n");
            fprintf(fp, "#       %s\n#\n", available_if(entry->ifdef));
	    enabled = 0;
        }

        for (line = entry->doc; line != NULL; line = line->next) {
            fprintf(fp, "#%s\n", line->data);
        }

        if (entry->default_value && strcmp(entry->default_value, "none") != 0) {
            snprintf(buf, sizeof(buf), "%s %s", entry->name, entry->default_value);
            lineAdd(&def, buf);
        }

        if (entry->default_if_none) {
            for (line = entry->default_if_none; line; line = line->next) {
                snprintf(buf, sizeof(buf), "%s %s", entry->name, line->data);
                lineAdd(&def, buf);
            }
        }

        if (entry->nocomment)
            blank = 0;

        if (!def && entry->doc && !entry->nocomment &&
                strcmp(entry->name, "comment") != 0)
            lineAdd(&def, "none");

        if (def && (entry->doc || entry->nocomment)) {
            if (blank)
                fprintf(fp, "#\n");

            fprintf(fp, "#Default:\n");

            while (def != NULL) {
                line = def;
                def = line->next;
                fprintf(fp, "# %s\n", line->data);
                xfree(line->data);
                xfree(line);
            }

            blank = 1;
        }

        if (entry->nocomment && blank)
            fprintf(fp, "#\n");

        for (line = entry->nocomment; line != NULL; line = line->next) {
	    if (!enabled && line->data[0] != '#')
		fprintf(fp, "#%s\n", line->data);
	    else
		fprintf(fp, "%s\n", line->data);
        }

        if (entry->doc != NULL) {
            fprintf(fp, "\n");
        }
    }
}