ngx_http_log_module.c

Nginx ("engine x") 是一个高性能的 HTTP 和 反向代理 服务器

    if (value == NULL || value->not_found) {
        return 1;
    }

    return value->len;
}


static u_char *
ngx_http_log_variable(ngx_http_request_t *r, u_char *buf, ngx_http_log_op_t *op)
{
    ngx_http_variable_value_t  *value;

    value = ngx_http_get_indexed_variable(r, op->data);

    if (value == NULL || value->not_found) {
        *buf = '-';
        return buf + 1;
    }

    return ngx_cpymem(buf, value->data, value->len);
}


static void *
ngx_http_log_create_main_conf(ngx_conf_t *cf)
{
    ngx_http_log_main_conf_t  *conf;

    ngx_http_log_fmt_t  *fmt;

    conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_log_main_conf_t));
    if (conf == NULL) {
        return NGX_CONF_ERROR;
    }

    if (ngx_array_init(&conf->formats, cf->pool, 4, sizeof(ngx_http_log_fmt_t))
        != NGX_OK)
    {
        return NGX_CONF_ERROR;
    }

    fmt = ngx_array_push(&conf->formats);
    if (fmt == NULL) {
        return NGX_CONF_ERROR;
    }

    fmt->name.len = sizeof("combined") - 1;
    fmt->name.data = (u_char *) "combined";

    fmt->ops = ngx_array_create(cf->pool, 16, sizeof(ngx_http_log_op_t));
    if (fmt->ops == NULL) {
        return NGX_CONF_ERROR;
    }

    return conf;
}


static void *
ngx_http_log_create_loc_conf(ngx_conf_t *cf)
{
    ngx_http_log_loc_conf_t  *conf;

    conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_log_loc_conf_t));
    if (conf == NULL) {
        return NGX_CONF_ERROR;
    }

    return conf;
}


static char *
ngx_http_log_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child)
{
    ngx_http_log_loc_conf_t *prev = parent;
    ngx_http_log_loc_conf_t *conf = child;

    ngx_http_log_t            *log;
    ngx_http_log_fmt_t        *fmt;
    ngx_http_log_main_conf_t  *lmcf;

    if (conf->logs || conf->off) {
        return NGX_CONF_OK;
    }

    *conf = *prev;

    if (conf->logs || conf->off) {
        return NGX_CONF_OK;
    }

    conf->logs = ngx_array_create(cf->pool, 2, sizeof(ngx_http_log_t));
    if (conf->logs == NULL) {
        return NGX_CONF_ERROR;
    }

    log = ngx_array_push(conf->logs);
    if (log == NULL) {
        return NGX_CONF_ERROR;
    }

    log->file = ngx_conf_open_file(cf->cycle, &ngx_http_access_log);
    if (log->file == NULL) {
        return NGX_CONF_ERROR;
    }

    log->disk_full_time = 0;
    log->error_log_time = 0;

    lmcf = ngx_http_conf_get_module_main_conf(cf, ngx_http_log_module);
    fmt = lmcf->formats.elts;

    /* the default "combined" format */
    log->ops = fmt[0].ops;
    lmcf->combined_used = 1;

    return NGX_CONF_OK;
}


static char *
ngx_http_log_set_log(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_http_log_loc_conf_t *llcf = conf;

    ssize_t                    buf;
    ngx_uint_t                 i;
    ngx_str_t                 *value, name;
    ngx_http_log_t            *log;
    ngx_http_log_fmt_t        *fmt;
    ngx_http_log_main_conf_t  *lmcf;

    value = cf->args->elts;

    if (ngx_strcmp(value[1].data, "off") == 0) {
        llcf->off = 1;
        return NGX_CONF_OK;
    }

    if (llcf->logs == NULL) {
        llcf->logs = ngx_array_create(cf->pool, 2, sizeof(ngx_http_log_t));
        if (llcf->logs == NULL) {
            return NGX_CONF_ERROR;
        }
    }

    lmcf = ngx_http_conf_get_module_main_conf(cf, ngx_http_log_module);

    log = ngx_array_push(llcf->logs);
    if (log == NULL) {
        return NGX_CONF_ERROR;
    }

    log->file = ngx_conf_open_file(cf->cycle, &value[1]);
    if (log->file == NULL) {
        return NGX_CONF_ERROR;
    }

    log->disk_full_time = 0;
    log->error_log_time = 0;

    if (cf->args->nelts >= 3) {
        name = value[2];

        if (ngx_strcmp(name.data, "combined") == 0) {
            lmcf->combined_used = 1;
        }

    } else {
        name.len = sizeof("combined") - 1;
        name.data = (u_char *) "combined";
        lmcf->combined_used = 1;
    }

    fmt = lmcf->formats.elts;
    for (i = 0; i < lmcf->formats.nelts; i++) {
        if (fmt[i].name.len == name.len
            && ngx_strcasecmp(fmt[i].name.data, name.data) == 0)
        {
            log->ops = fmt[i].ops;
            goto buffer;
        }
    }

    ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                       "unknown log format \"%V\"", &name);
    return NGX_CONF_ERROR;

buffer:

    if (cf->args->nelts == 4) {
        if (ngx_strncmp(value[3].data, "buffer=", 7) != 0) {
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "invalid parameter \"%V\"", &value[3]);
            return NGX_CONF_ERROR;
        }

        name.len = value[3].len - 7;
        name.data = value[3].data + 7;

        buf = ngx_parse_size(&name);

        if (buf == NGX_ERROR) {
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "invalid parameter \"%V\"", &value[3]);
            return NGX_CONF_ERROR;
        }

        if (log->file->buffer && log->file->last - log->file->pos != buf) {
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "access_log \"%V\" already defined "
                               "with different buffer size", &value[1]);
            return NGX_CONF_ERROR;
        }

        log->file->buffer = ngx_palloc(cf->pool, buf);
        if (log->file->buffer == NULL) {
            return NGX_CONF_ERROR;
        }

        log->file->pos = log->file->buffer;
        log->file->last = log->file->buffer + buf;
    }

    return NGX_CONF_OK;
}


static char *
ngx_http_log_set_format(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_http_log_main_conf_t *lmcf = conf;

    ngx_str_t           *value;
    ngx_uint_t           i;
    ngx_http_log_fmt_t  *fmt;

    value = cf->args->elts;

    fmt = lmcf->formats.elts;
    for (i = 0; i < lmcf->formats.nelts; i++) {
        if (fmt[i].name.len == value[1].len
            && ngx_strcmp(fmt[i].name.data, value[1].data) == 0)
        {
            return "duplicate \"log_format\" name";
        }
    }

    fmt = ngx_array_push(&lmcf->formats);
    if (fmt == NULL) {
        return NGX_CONF_ERROR;
    }

    fmt->name = value[1];

    fmt->ops = ngx_array_create(cf->pool, 16, sizeof(ngx_http_log_op_t));
    if (fmt->ops == NULL) {
        return NGX_CONF_ERROR;
    }

    return ngx_http_log_compile_format(cf, fmt->ops, cf->args, 2);
}


static char *
ngx_http_log_compile_format(ngx_conf_t *cf, ngx_array_t *ops,
    ngx_array_t *args, ngx_uint_t s)
{
    u_char              *data, *p, ch;
    size_t               i, len;
    ngx_str_t           *value, var;
    ngx_uint_t           bracket;
    ngx_http_log_op_t   *op;
    ngx_http_log_var_t  *v;

    value = args->elts;

    for ( /* void */ ; s < args->nelts; s++) {

        for (i = 0; i < value[s].len; i++) {
            if (value[s].data[i] != '%') {
                continue;
            }

            ch = value[s].data[i + 1];

            if ((ch >= 'A' && ch <= 'Z')
                 || (ch >= 'a' && ch <= 'z')
                 || ch == '{')
            {
                ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                     "the parameters in the \"%%name\" form are not supported, "
                     "use the \"$variable\" instead");

                return NGX_CONF_ERROR;
            }
        }

        i = 0;

        while (i < value[s].len) {

            op = ngx_array_push(ops);
            if (op == NULL) {
                return NGX_CONF_ERROR;
            }

            data = &value[s].data[i];

            if (value[s].data[i] == '$') {

                if (++i == value[s].len) {
                    goto invalid;
                }

                if (value[s].data[i] == '{') {
                    bracket = 1;

                    if (++i == value[s].len) {
                        goto invalid;
                    }

                    var.data = &value[s].data[i];

                } else {
                    bracket = 0;
                    var.data = &value[s].data[i];
                }

                for (var.len = 0; i < value[s].len; i++, var.len++) {
                    ch = value[s].data[i];

                    if (ch == '}' && bracket) {
                        i++;
                        bracket = 0;
                        break;
                    }

                    if ((ch >= 'A' && ch <= 'Z')
                        || (ch >= 'a' && ch <= 'z')
                        || (ch >= '0' && ch <= '9')
                        || ch == '_')
                    {
                        continue;
                    }

                    break;
                }

                if (bracket) {
                    ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                       "the closing bracket in \"%V\" "
                                       "variable is missing", &var);
                    return NGX_CONF_ERROR;
                }

                if (var.len == 0) {
                    goto invalid;
                }

                if (ngx_strncmp(var.data, "apache_bytes_sent", 17) == 0) {
                    ngx_conf_log_error(NGX_LOG_WARN, cf, 0,
                        "use \"$body_bytes_sent\" instead of "
                        "\"$apache_bytes_sent\"");
                }

                for (v = ngx_http_log_vars; v->name.len; v++) {

                    if (v->name.len == var.len
                        && ngx_strncmp(v->name.data, var.data, var.len) == 0)
                    {
                        op->len = v->len;
                        op->getlen = NULL;
                        op->run = v->run;
                        op->data = 0;

                        goto found;
                    }
                }

                if (ngx_http_log_variable_compile(cf, op, &var) != NGX_OK) {
                    return NGX_CONF_ERROR;
                }

            found:

                continue;
            }

            i++;

            while (i < value[s].len && value[s].data[i] != '$') {
                i++;
            }

            len = &value[s].data[i] - data;

            if (len) {

                op->len = len;
                op->getlen = NULL;

                if (len <= sizeof(uintptr_t)) {
                    op->run = ngx_http_log_copy_short;
                    op->data = 0;

                    while (len--) {
                        op->data <<= 8;
                        op->data |= data[len];
                    }

                } else {
                    op->run = ngx_http_log_copy_long;

                    p = ngx_palloc(cf->pool, len);
                    if (p == NULL) {
                        return NGX_CONF_ERROR;
                    }

                    ngx_memcpy(p, data, len);
                    op->data = (uintptr_t) p;
                }
            }
        }
    }

    return NGX_CONF_OK;

invalid:

    ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid parameter \"%s\"", data);

    return NGX_CONF_ERROR;
}


static ngx_int_t
ngx_http_log_init(ngx_conf_t *cf)
{
    ngx_str_t                  *value;
    ngx_array_t                 a;
    ngx_http_handler_pt        *h;
    ngx_http_log_fmt_t         *fmt;
    ngx_http_log_main_conf_t   *lmcf;
    ngx_http_core_main_conf_t  *cmcf;

    lmcf = ngx_http_conf_get_module_main_conf(cf, ngx_http_log_module);

    if (lmcf->combined_used) {
        if (ngx_array_init(&a, cf->pool, 1, sizeof(ngx_str_t)) != NGX_OK) {
            return NGX_ERROR;
        }

        value = ngx_array_push(&a);
        if (value == NULL) {
            return NGX_ERROR;
        }

        *value = ngx_http_combined_fmt;
        fmt = lmcf->formats.elts;

        if (ngx_http_log_compile_format(cf, fmt->ops, &a, 0)
            != NGX_CONF_OK)
        {
            return NGX_ERROR;
        }
    }

    cmcf = ngx_http_conf_get_module_main_conf(cf, ngx_http_core_module);

    h = ngx_array_push(&cmcf->phases[NGX_HTTP_LOG_PHASE].handlers);
    if (h == NULL) {
        return NGX_ERROR;
    }

    *h = ngx_http_log_handler;

    return NGX_OK;
}