ngx_http_process_request_uri

src\http\ngx_http_request.c

ngx_int_t
ngx_http_process_request_uri(ngx_http_request_t *r)
{
    ngx_http_core_srv_conf_t  *cscf;

    if (r->args_start) {
        r->uri.len = r->args_start - 1 - r->uri_start;
    } else {
        r->uri.len = r->uri_end - r->uri_start;
    }

    if (r->complex_uri || r->quoted_uri || r->empty_path_in_uri) {

        if (r->empty_path_in_uri) {
            r->uri.len++;
        }

        r->uri.data = ngx_pnalloc(r->pool, r->uri.len);
        if (r->uri.data == NULL) {
            ngx_http_close_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
            return NGX_ERROR;
        }

        cscf = ngx_http_get_module_srv_conf(r, ngx_http_core_module);

        if (ngx_http_parse_complex_uri(r, cscf->merge_slashes) != NGX_OK) {
            r->uri.len = 0;

            ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
                          "client sent invalid request");
            ngx_http_finalize_request(r, NGX_HTTP_BAD_REQUEST);
            return NGX_ERROR;
        }

    } else {
        r->uri.data = r->uri_start;
    }

    r->unparsed_uri.len = r->uri_end - r->uri_start;
    r->unparsed_uri.data = r->uri_start;

    r->valid_unparsed_uri = r->empty_path_in_uri ? 0 : 1;

    if (r->uri_ext) {
        if (r->args_start) {
            r->exten.len = r->args_start - 1 - r->uri_ext;
        } else {
            r->exten.len = r->uri_end - r->uri_ext;
        }

        r->exten.data = r->uri_ext;
    }

    if (r->args_start && r->uri_end > r->args_start) {
        r->args.len = r->uri_end - r->args_start;
        r->args.data = r->args_start;
    }

#if (NGX_WIN32)
    {
    u_char  *p, *last;

    p = r->uri.data;
    last = r->uri.data + r->uri.len;

    while (p < last) {

        if (*p++ == ':') {

            /*
             * this check covers "::$data", "::$index_allocation" and
             * ":$i30:$index_allocation"
             */

            if (p < last && *p == '$') {
                ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
                              "client sent unsafe win32 URI");
                ngx_http_finalize_request(r, NGX_HTTP_BAD_REQUEST);
                return NGX_ERROR;
            }
        }
    }

    p = r->uri.data + r->uri.len - 1;

    while (p > r->uri.data) {

        if (*p == ' ') {
            p--;
            continue;
        }

        if (*p == '.') {
            p--;
            continue;
        }

        break;
    }

    if (p != r->uri.data + r->uri.len - 1) {
        r->uri.len = p + 1 - r->uri.data;
        ngx_http_set_exten(r);
    }

    }
#endif

    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "http uri: \"%V\"", &r->uri);

    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "http args: \"%V\"", &r->args);

    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "http exten: \"%V\"", &r->exten);

    return NGX_OK;
}

这个函数是Nginx中处理HTTP请求URI的核心函数

---

详解

ngx_int_t
ngx_http_process_request_uri(ngx_http_request_t *r)
{

定义函数，接收一个HTTP请求对象指针r，返回整型状态码

---

    ngx_http_core_srv_conf_t  *cscf;

声明核心服务器配置结构体指针

---

    if (r->args_start) {
        r->uri.len = r->args_start - 1 - r->uri_start;
    } else {
        r->uri.len = r->uri_end - r->uri_start;
    }

如果有查询参数(args_start存在)，URI长度是参数起始位置减1(去掉问号)减去URI起始位置
如果没有查询参数，URI长度是URI结束位置减去起始位置

---

    if (r->complex_uri || r->quoted_uri || r->empty_path_in_uri) {

        if (r->empty_path_in_uri) {
            r->uri.len++;
        }

检查是否是复杂URI(包含编码字符)、引用URI或空路径URI
如果是空路径URI，增加URI长度(可能为后续处理做准备)

---

        r->uri.data = ngx_pnalloc(r->pool, r->uri.len);
        if (r->uri.data == NULL) {
            ngx_http_close_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
            return NGX_ERROR;
        }

        cscf = ngx_http_get_module_srv_conf(r, ngx_http_core_module);

        if (ngx_http_parse_complex_uri(r, cscf->merge_slashes) != NGX_OK) {
            r->uri.len = 0;

            ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
                          "client sent invalid request");
            ngx_http_finalize_request(r, NGX_HTTP_BAD_REQUEST);
            return NGX_ERROR;
        }

    } else {
        r->uri.data = r->uri_start;
    }

对于简单URI，直接使用原始URI起始指针

---

    r->unparsed_uri.len = r->uri_end - r->uri_start;
    r->unparsed_uri.data = r->uri_start;

    r->valid_unparsed_uri = r->empty_path_in_uri ? 0 : 1;

设置未解析URI的长度和指针(原始URI)
设置有效未解析URI标志(空路径URI时为0)

---

    if (r->uri_ext) {
        if (r->args_start) {
            r->exten.len = r->args_start - 1 - r->uri_ext;
        } else {
            r->exten.len = r->uri_end - r->uri_ext;
        }

        r->exten.data = r->uri_ext;
    }

如果有URI扩展部分
计算扩展名长度(考虑查询参数)
设置扩展名数据指针

---

    if (r->args_start && r->uri_end > r->args_start) {
        r->args.len = r->uri_end - r->args_start;
        r->args.data = r->args_start;
    }

如果有查询参数且参数部分有效
设置参数长度和数据指针

---

#if (NGX_WIN32)
    {
    u_char  *p, *last;

    p = r->uri.data;
    last = r->uri.data + r->uri.len;

    while (p < last) {

        if (*p++ == ':') {

            /*
             * this check covers "::$data", "::$index_allocation" and
             * ":$i30:$index_allocation"
             */

            if (p < last && *p == '$') {
                ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
                              "client sent unsafe win32 URI");
                ngx_http_finalize_request(r, NGX_HTTP_BAD_REQUEST);
                return NGX_ERROR;
            }
        }
    }

    p = r->uri.data + r->uri.len - 1;

    while (p > r->uri.data) {

        if (*p == ' ') {
            p--;
            continue;
        }

        if (*p == '.') {
            p--;
            continue;
        }

        break;
    }

    if (p != r->uri.data + r->uri.len - 1) {
        r->uri.len = p + 1 - r->uri.data;
        ngx_http_set_exten(r);
    }

    }
#endif

Windows平台特有处理

---

    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "http uri: \"%V\"", &r->uri);

    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "http args: \"%V\"", &r->args);

    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "http exten: \"%V\"", &r->exten);

    return NGX_OK;
}