core.c

Apache HTTP Server 是一个功能强大的灵活的与HTTP/1.1相兼容的web服务器.这里给出的是Apache HTTP服务器的源码。

        return errmsg;

    conf->d = apr_pstrdup(cmd->pool, cmd->path);     /* No mangling, please */
    conf->d_is_fnmatch = apr_fnmatch_test(conf->d) != 0;
    conf->r = r;

    ap_add_per_url_conf(cmd->server, new_url_conf);

    if (*arg != '\0') {
        return apr_pstrcat(cmd->pool, "Multiple ", thiscmd->name,
                           "> arguments not (yet) supported.", NULL);
    }

    cmd->path = old_path;
    cmd->override = old_overrides;

    return NULL;
}

static const char *filesection(cmd_parms *cmd, void *mconfig, const char *arg)
{
    const char *errmsg;
    const char *endp = ap_strrchr_c(arg, '>');
    int old_overrides = cmd->override;
    char *old_path = cmd->path;
    core_dir_config *conf;
    regex_t *r = NULL;
    const command_rec *thiscmd = cmd->cmd;
    core_dir_config *c = mconfig;
    ap_conf_vector_t *new_file_conf = ap_create_per_dir_config(cmd->pool);
    const char *err = ap_check_cmd_context(cmd, NOT_IN_LIMIT|NOT_IN_LOCATION);

    if (err != NULL) {
        return err;
    }

    if (endp == NULL) {
        return unclosed_directive(cmd);
    }

    arg = apr_pstrndup(cmd->pool, arg, endp - arg);

    cmd->path = ap_getword_conf(cmd->pool, &arg);
    /* Only if not an .htaccess file */
    if (!old_path) {
        cmd->override = OR_ALL|ACCESS_CONF;
    }

    if (thiscmd->cmd_data) { /* <FilesMatch> */
        r = ap_pregcomp(cmd->pool, cmd->path, REG_EXTENDED|USE_ICASE);
        if (!r) {
            return "Regex could not be compiled";
        }
    }
    else if (!strcmp(cmd->path, "~")) {
        cmd->path = ap_getword_conf(cmd->pool, &arg);
        r = ap_pregcomp(cmd->pool, cmd->path, REG_EXTENDED|USE_ICASE);
        if (!r) {
            return "Regex could not be compiled";
        }
    }
    else {
        char *newpath;
        /* Ensure that the pathname is canonical, but we
         * can't test the case/aliases without a fixed path */
        if (apr_filepath_merge(&newpath, "", cmd->path,
                               0, cmd->pool) != APR_SUCCESS)
                return apr_pstrcat(cmd->pool, "<Files \"", cmd->path,
                               "\"> is invalid.", NULL);
        cmd->path = newpath;
    }

    /* initialize our config and fetch it */
    conf = ap_set_config_vectors(cmd->server, new_file_conf, cmd->path,
                                 &core_module, cmd->pool);

    errmsg = ap_walk_config(cmd->directive->first_child, cmd, new_file_conf);
    if (errmsg != NULL)
        return errmsg;

    conf->d = cmd->path;
    conf->d_is_fnmatch = apr_fnmatch_test(conf->d) != 0;
    conf->r = r;

    ap_add_file_conf(c, new_file_conf);

    if (*arg != '\0') {
        return apr_pstrcat(cmd->pool, "Multiple ", thiscmd->name,
                           "> arguments not (yet) supported.", NULL);
    }

    cmd->path = old_path;
    cmd->override = old_overrides;

    return NULL;
}

static const char *start_ifmod(cmd_parms *cmd, void *mconfig, const char *arg)
{
    const char *endp = ap_strrchr_c(arg, '>');
    int not = (arg[0] == '!');
    module *found;

    if (endp == NULL) {
        return unclosed_directive(cmd);
    }

    arg = apr_pstrndup(cmd->pool, arg, endp - arg);

    if (not) {
        arg++;
    }

    found = ap_find_linked_module(arg);

    if ((!not && found) || (not && !found)) {
        ap_directive_t *parent = NULL;
        ap_directive_t *current = NULL;
        const char *retval;

        retval = ap_build_cont_config(cmd->pool, cmd->temp_pool, cmd,
                                      &current, &parent, "<IfModule");
        *(ap_directive_t **)mconfig = current;
        return retval;
    }
    else {
        *(ap_directive_t **)mconfig = NULL;
        return ap_soak_end_container(cmd, "<IfModule");
    }
}

AP_DECLARE(int) ap_exists_config_define(const char *name)
{
    char **defines;
    int i;

    defines = (char **)ap_server_config_defines->elts;
    for (i = 0; i < ap_server_config_defines->nelts; i++) {
        if (strcmp(defines[i], name) == 0) {
            return 1;
        }
    }

    return 0;
}

static const char *start_ifdefine(cmd_parms *cmd, void *dummy, const char *arg)
{
    const char *endp;
    int defined;
    int not = 0;

    endp = ap_strrchr_c(arg, '>');
    if (endp == NULL) {
        return unclosed_directive(cmd);
    }

    arg = apr_pstrndup(cmd->pool, arg, endp - arg);

    if (arg[0] == '!') {
        not = 1;
        arg++;
    }

    defined = ap_exists_config_define(arg);
    if ((!not && defined) || (not && !defined)) {
        ap_directive_t *parent = NULL;
        ap_directive_t *current = NULL;
        const char *retval;

        retval = ap_build_cont_config(cmd->pool, cmd->temp_pool, cmd,
                                      &current, &parent, "<IfDefine");
        *(ap_directive_t **)dummy = current;
        return retval;
    }
    else {
        *(ap_directive_t **)dummy = NULL;
        return ap_soak_end_container(cmd, "<IfDefine");
    }
}

/* httpd.conf commands... beginning with the <VirtualHost> business */

static const char *virtualhost_section(cmd_parms *cmd, void *dummy,
                                       const char *arg)
{
    server_rec *main_server = cmd->server, *s;
    const char *errmsg;
    const char *endp = ap_strrchr_c(arg, '>');
    apr_pool_t *p = cmd->pool;

    const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
    if (err != NULL) {
        return err;
    }

    if (endp == NULL) {
        return unclosed_directive(cmd);
    }

    arg = apr_pstrndup(cmd->pool, arg, endp - arg);

    /* FIXME: There's another feature waiting to happen here -- since you
        can now put multiple addresses/names on a single <VirtualHost>
        you might want to use it to group common definitions and then
        define other "subhosts" with their individual differences.  But
        personally I'd rather just do it with a macro preprocessor. -djg */
    if (main_server->is_virtual) {
        return "<VirtualHost> doesn't nest!";
    }

    errmsg = ap_init_virtual_host(p, arg, main_server, &s);
    if (errmsg) {
        return errmsg;
    }

    s->next = main_server->next;
    main_server->next = s;

    s->defn_name = cmd->directive->filename;
    s->defn_line_number = cmd->directive->line_num;

    cmd->server = s;

    errmsg = ap_walk_config(cmd->directive->first_child, cmd,
                            s->lookup_defaults);

    cmd->server = main_server;

    return errmsg;
}

static const char *set_server_alias(cmd_parms *cmd, void *dummy,
                                    const char *arg)
{
    if (!cmd->server->names) {
        return "ServerAlias only used in <VirtualHost>";
    }

    while (*arg) {
        char **item, *name = ap_getword_conf(cmd->pool, &arg);

        if (ap_is_matchexp(name)) {
            item = (char **)apr_array_push(cmd->server->wild_names);
        }
        else {
            item = (char **)apr_array_push(cmd->server->names);
        }

        *item = name;
    }

    return NULL;
}

static const char *set_server_string_slot(cmd_parms *cmd, void *dummy,
                                          const char *arg)
{
    /* This one's pretty generic... */

    int offset = (int)(long)cmd->info;
    char *struct_ptr = (char *)cmd->server;

    const char *err = ap_check_cmd_context(cmd,
                                           NOT_IN_DIR_LOC_FILE|NOT_IN_LIMIT);
    if (err != NULL) {
        return err;
    }

    *(const char **)(struct_ptr + offset) = arg;
    return NULL;
}

static const char *server_hostname_port(cmd_parms *cmd, void *dummy, const char *arg)
{
    const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_LOC_FILE|NOT_IN_LIMIT);
    const char *portstr;
    int port;

    if (err != NULL) {
        return err;
    }

    portstr = ap_strchr_c(arg, ':');
    if (portstr) {
        cmd->server->server_hostname = apr_pstrndup(cmd->pool, arg,
                                                    portstr - arg);
        portstr++;
        port = atoi(portstr);
        if (port <= 0 || port >= 65536) { /* 65536 == 1<<16 */
            return apr_pstrcat(cmd->temp_pool, "The port number \"", arg,
                          "\" is outside the appropriate range "
                          "(i.e., 1..65535).", NULL);
        }
    }
    else {
        cmd->server->server_hostname = apr_pstrdup(cmd->pool, arg);
        port = 0;
    }

    cmd->server->port = port;
    return NULL;
}

static const char *set_signature_flag(cmd_parms *cmd, void *d_,
                                      const char *arg)
{
    core_dir_config *d = d_;
    const char *err = ap_check_cmd_context(cmd, NOT_IN_LIMIT);

    if (err != NULL) {
        return err;
    }

    if (strcasecmp(arg, "On") == 0) {
        d->server_signature = srv_sig_on;
    }
    else if (strcasecmp(arg, "Off") == 0) {
        d->server_signature = srv_sig_off;
    }
    else if (strcasecmp(arg, "EMail") == 0) {
        d->server_signature = srv_sig_withmail;
    }
    else {
        return "ServerSignature: use one of: off | on | email";
    }

    return NULL;
}

static const char *set_server_root(cmd_parms *cmd, void *dummy,
                                   const char *arg)
{
    const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);

    if (err != NULL) {
        return err;
    }

    if ((apr_filepath_merge((char**)&ap_server_root, NULL, arg,
                            APR_FILEPATH_TRUENAME, cmd->pool) != APR_SUCCESS)
        || !ap_is_directory(cmd->pool, ap_server_root)) {
        return "ServerRoot must be a valid directory";
    }

    return NULL;
}

static const char *set_timeout(cmd_parms *cmd, void *dummy, const char *arg)
{
    const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_LOC_FILE|NOT_IN_LIMIT);

    if (err != NULL) {
        return err;
    }

    cmd->server->timeout = apr_time_from_sec(atoi(arg));
    return NULL;
}

static const char *set_idcheck(cmd_parms *cmd, void *d_, int arg)
{
    core_dir_config *d = d_;
    const char *err = ap_check_cmd_context(cmd, NOT_IN_LIMIT);

    if (err != NULL) {
        return err;
    }

    d->do_rfc1413 = arg != 0;
    return NULL;
}

static const char *set_allow2f(cmd_parms *cmd, void *d_, int arg)
{
    core_dir_config *d = d_;
    const char *err = ap_check_cmd_context(cmd, NOT_IN_LIMIT);

    if (err != NULL) {
        return err;
    }

    d->allow_encoded_slashes = arg != 0;
    return NULL;
}

static const char *set_hostname_lookups(cmd_parms *cmd, void *d_,
                                        const char *arg)
{
    core_dir_config *d = d_;
    const char *err = ap_check_cmd_context(cmd, NOT_IN_LIMIT);

    if (err != NULL) {
        return err;
    }

    if (!strcasecmp(arg, "on")) {
        d->hostname_lookups = HOSTNAME_LOOKUP_ON;
    }
    else if (!strcasecmp(arg, "off")) {
        d->hostname_lookups = HOSTNAME_LOOKUP_OFF;
    }
    else if (!strcasecmp(arg, "double")) {
        d->hostname_lookups = HOSTNAME_LOOKUP_DOUBLE;
    }
    else {
        return "parameter must be 'on', 'off', or 'double'";
    }

    return NULL;
}

static const char *set_serverpath(cmd_parms *cmd, void *dummy,
                                  const char *arg)
{
    const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_LOC_FILE|NOT_IN_LIMIT);

    if (err != NULL) {
        return err;
    }

    cmd->server->path = arg;
    cmd->server->pathlen = strlen(arg);
    return NULL;
}

static const char *set_content_md5(cmd_parms *cmd, void *d_, int arg)
{
    core_dir_config *d = d_;
    const char *err = ap_check_cmd_context(cmd, NOT_IN_LIMIT);

    if (err != NULL) {
        return err;
    }

    d->content_md5 = arg != 0;
    return NULL;
}

static const char *set_accept_path_info(cmd_parms *cmd, void *d_, const char *arg)
{
    core_dir_config *d = d_;

    if (strcasecmp(arg, "on") == 0) {
        d->accept_path_info = AP_REQ_ACCEPT_PATH