read_config.c

snmp up 2

/*
 * read_config.c
 */

#include <net-snmp/net-snmp-config.h>

#include <stdio.h>
#include <ctype.h>
#if HAVE_STDLIB_H
#include <stdlib.h>
#endif
#if HAVE_STRING_H
#include <string.h>
#else
#include <strings.h>
#endif
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <sys/types.h>
#if HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#if TIME_WITH_SYS_TIME
# ifdef WIN32
#  include <sys/timeb.h>
# else
#  include <sys/time.h>
# endif
# include <time.h>
#else
# if HAVE_SYS_TIME_H
#  include <sys/time.h>
# else
#  include <time.h>
# endif
#endif
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#if HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#if HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#if HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
#if HAVE_WINSOCK_H
#include <winsock.h>
#endif
#if HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#if HAVE_NETDB_H
#include <netdb.h>
#endif
#include <errno.h>

#if HAVE_DMALLOC_H
#include <dmalloc.h>
#endif

#include <net-snmp/types.h>
#include <net-snmp/output_api.h>
#include <net-snmp/config_api.h>
#include <net-snmp/library/read_config.h>       /* for "internal" definitions */
#include <net-snmp/utilities.h>

#include <net-snmp/library/mib.h>
#include <net-snmp/library/parse.h>
#include <net-snmp/library/snmp_api.h>
#include <net-snmp/library/callback.h>

#include <windows.h>

static int      config_errors;

struct config_files *config_files = NULL;

struct config_line *
register_prenetsnmp_mib_handler(const char *type,
                                const char *token,
                                void (*parser) (const char *, char *),
                                void (*releaser) (void), const char *help)
{
    struct config_line *ltmp;
    ltmp = register_config_handler(type, token, parser, releaser, help);
    if (ltmp != NULL)
        ltmp->config_time = PREMIB_CONFIG;
    return (ltmp);
}

struct config_line *
register_app_prenetsnmp_mib_handler(const char *token,
                                    void (*parser) (const char *, char *),
                                    void (*releaser) (void),
                                    const char *help)
{
    return (register_prenetsnmp_mib_handler
            (NULL, token, parser, releaser, help));
}

/*******************************************************************-o-******
 * register_config_handler
 *
 * Parameters:
 *	*type
 *	*token
 *	*parser
 *	*releaser
 *      
 * Returns:
 *	Pointer to a new config line entry  -OR-  NULL on error.
 */
struct config_line *
register_config_handler(const char *type_param,
                        const char *token,
                        void (*parser) (const char *, char *),
                        void (*releaser) (void), const char *help)
{
    struct config_files **ctmp = &config_files;
    struct config_line **ltmp;
    const char     *type = type_param;

    if (type == NULL) {
        type = netsnmp_ds_get_string(NETSNMP_DS_LIBRARY_ID, 
				     NETSNMP_DS_LIB_APPTYPE);
    }

    /*
     * Find type in current list  -OR-  create a new file type.
     */
    while (*ctmp != NULL && strcmp((*ctmp)->fileHeader, type)) {
        ctmp = &((*ctmp)->next);
    }

    if (*ctmp == NULL) {
        *ctmp = (struct config_files *)
            calloc(1, sizeof(struct config_files));
        if (!*ctmp) {
            return NULL;
        }

        (*ctmp)->fileHeader = strdup(type);
    }

    /*
     * Find parser type in current list  -OR-  create a new
     * line parser entry.
     */
    ltmp = &((*ctmp)->start);

    while (*ltmp != NULL && strcmp((*ltmp)->config_token, token)) {
        ltmp = &((*ltmp)->next);
    }

    if (*ltmp == NULL) {
        *ltmp = (struct config_line *)
            calloc(1, sizeof(struct config_line));
        if (!*ltmp) {
            return NULL;
        }

        (*ltmp)->config_time = NORMAL_CONFIG;
        (*ltmp)->config_token = strdup(token);
        if (help != NULL)
            (*ltmp)->help = strdup(help);
    }

    /*
     * Add/Replace the parse/free functions for the given line type
     * in the given file type.
     */
    (*ltmp)->parse_line = parser;
    (*ltmp)->free_func = releaser;

    return (*ltmp);

}                               /* end register_config_handler() */

struct config_line *
register_app_config_handler(const char *token,
                            void (*parser) (const char *, char *),
                            void (*releaser) (void), const char *help)
{
    return (register_config_handler(NULL, token, parser, releaser, help));
}

void
unregister_config_handler(const char *type_param, const char *token)
{
    struct config_files **ctmp = &config_files;
    struct config_line **ltmp, *ltmp2;
    const char     *type = type_param;

    if (type == NULL) {
        type = netsnmp_ds_get_string(NETSNMP_DS_LIBRARY_ID, 
				     NETSNMP_DS_LIB_APPTYPE);
    }

    /*
     * find type in current list 
     */
    while (*ctmp != NULL && strcmp((*ctmp)->fileHeader, type)) {
        ctmp = &((*ctmp)->next);
    }

    if (*ctmp == NULL) {
        /*
         * Not found, return. 
         */
        return;
    }

    ltmp = &((*ctmp)->start);
    if (*ltmp == NULL) {
        /*
         * Not found, return. 
         */
        return;
    }
    if (strcmp((*ltmp)->config_token, token) == 0) {
        /*
         * found it at the top of the list 
         */
        ltmp2 = (*ltmp)->next;
        free((*ltmp)->config_token);
        SNMP_FREE((*ltmp)->help);
        free(*ltmp);
        (*ctmp)->start = ltmp2;
        return;
    }
    while ((*ltmp)->next != NULL
           && strcmp((*ltmp)->next->config_token, token)) {
        ltmp = &((*ltmp)->next);
    }
    if ((*ltmp)->next != NULL) {
        free((*ltmp)->next->config_token);
        SNMP_FREE((*ltmp)->next->help);
        ltmp2 = (*ltmp)->next->next;
        free((*ltmp)->next);
        (*ltmp)->next = ltmp2;
    }
}

void
unregister_app_config_handler(const char *token)
{
    unregister_config_handler(NULL, token);
}

void
unregister_all_config_handlers()
{
    struct config_files *ctmp, *save;
    struct config_line *ltmp;

    free_config();

    /*
     * Keep using config_files until there are no more! 
     */
    for (ctmp = config_files; ctmp;) {
        for (ltmp = ctmp->start; ltmp; ltmp = ctmp->start) {
            unregister_config_handler(ctmp->fileHeader,
                                      ltmp->config_token);
        }
        free(ctmp->fileHeader);
        save = ctmp->next;
        free(ctmp);
        ctmp = save;
        config_files = save;
    }
}

#ifdef TESTING
void
print_config_handlers(void)
{
    struct config_files *ctmp = config_files;
    struct config_line *ltmp;

    for (; ctmp != NULL; ctmp = ctmp->next) {
        DEBUGMSGTL(("read_config", "read_conf: %s\n", ctmp->fileHeader));
        for (ltmp = ctmp->start; ltmp != NULL; ltmp = ltmp->next)
            DEBUGMSGTL(("read_config", "                   %s\n",
                        ltmp->config_token));
    }
}
#endif

int             linecount;
const char     *curfilename;

struct config_line *
read_config_get_handlers(const char *type)
{
    struct config_files *ctmp = config_files;
    for (; ctmp != NULL && strcmp(ctmp->fileHeader, type);
         ctmp = ctmp->next);
    if (ctmp)
        return ctmp->start;
    return NULL;
}

void
read_config_with_type(const char *filename, const char *type)
{
    struct config_line *ctmp = read_config_get_handlers(type);
    if (ctmp)
        read_config(filename, ctmp, EITHER_CONFIG);
    else
        DEBUGMSGTL(("read_config",
                    "read_config: I have no registrations for type:%s,file:%s\n",
                    type, filename));
}


struct config_line *
read_config_find_handler(struct config_line *line_handlers,
                         const char *token)
{
    struct config_line *lptr;

    for (lptr = line_handlers; lptr != NULL; lptr = lptr->next) {
        if (!strcasecmp(token, lptr->config_token)) {
            return lptr;
        }
    }
    return NULL;
}


/*
 * searches a config_line linked list for a match 
 */
int
run_config_handler(struct config_line *lptr,
                   const char *token, char *cptr, int when)
{
    char            tmpbuf[STRINGMAX];
    lptr = read_config_find_handler(lptr, token);
    if (lptr != NULL) {
        if (when == EITHER_CONFIG || lptr->config_time == when) {
            DEBUGMSGTL(("read_config",
                        "Found a parser.  Calling it: %s / %s\n", token,
                        cptr));
            (*(lptr->parse_line)) (token, cptr);
        }
    } else if (when != PREMIB_CONFIG && 
	       !netsnmp_ds_get_boolean(NETSNMP_DS_LIBRARY_ID, 
				       NETSNMP_DS_LIB_NO_TOKEN_WARNINGS)) {
        snprintf(tmpbuf, sizeof(tmpbuf), "Unknown token: %s.", token);
        tmpbuf[ sizeof(tmpbuf)-1 ] = 0;
        config_pwarn(tmpbuf);
        return SNMPERR_GENERR;
    }
    return SNMPERR_SUCCESS;
}

/*
 * takens an arbitrary string and tries to intepret it based on the
 * known configruation handlers for all registered types.  May produce
 * inconsistent results when multiple tokens of the same name are
 * registered under different file types. 
 */

/*
 * we allow = delimeters here 
 */
#define SNMP_CONFIG_DELIMETERS " \t="

int
snmp_config_when(char *line, int when)
{
    char           *cptr, buf[STRINGMAX], tmpbuf[STRINGMAX];
    struct config_line *lptr = NULL;
    struct config_files *ctmp = config_files;

    if (line == NULL) {
        config_perror("snmp_config() called with a null string.");
        return SNMPERR_GENERR;
    }

    strncpy(buf, line, STRINGMAX);
    buf[STRINGMAX - 1] = '\0';
    cptr = strtok(buf, SNMP_CONFIG_DELIMETERS);
    if (cptr && cptr[0] == '[') {
        if (cptr[strlen(cptr) - 1] != ']') {
            config_perror("no matching ']'");
            return SNMPERR_GENERR;
        }
        lptr = read_config_get_handlers(cptr + 1);
        if (lptr == NULL) {
            snprintf(tmpbuf,  sizeof(tmpbuf),
                     "No handlers regestered for type %s.",
                    cptr + 1);
            tmpbuf[ sizeof(tmpbuf)-1 ] = 0;
            config_perror(tmpbuf);
            return SNMPERR_GENERR;
        }
        cptr = strtok(NULL, SNMP_CONFIG_DELIMETERS);
        lptr = read_config_find_handler(lptr, cptr);
    } else {
        /*
         * we have to find a token 
         */
        for (; ctmp != NULL && lptr == NULL; ctmp = ctmp->next)
            lptr = read_config_find_handler(ctmp->start, cptr);
    }
    if (lptr == NULL && netsnmp_ds_get_boolean(NETSNMP_DS_LIBRARY_ID, 
					  NETSNMP_DS_LIB_NO_TOKEN_WARNINGS)) {
        snprintf(tmpbuf, sizeof(tmpbuf), "Unknown token: %s.", cptr);
        tmpbuf[ sizeof(tmpbuf)-1 ] = 0;
        config_pwarn(tmpbuf);
        return SNMPERR_GENERR;