1# CivetWeb API Reference 2 3CivetWeb is often used as HTTP and HTTPS library inside a larger application. 4A C API is available to integrate the CivetWeb functionality in a larger 5codebase. A C++ wrapper is also available, although it is not guaranteed 6that all functionality available through the C API can also be accessed 7from C++. This document describes the public C API. Basic usage examples of 8the API can be found in [Embedding.md](Embedding.md), as well as in the 9examples directory. 10 11## Macros 12 13| Macro | Description | 14| :--- | :--- | 15| **`CIVETWEB_VERSION`** | The current version of the software as a string with the major and minor version number separated with a dot. For version 1.9, this string will have the value "1.9", for the first patch of this version "1.9.1". | 16| **`CIVETWEB_VERSION_MAJOR`** | The current major version as number, e.g., (1) for version 1.9. | 17| **`CIVETWEB_VERSION_MINOR`** | The current minor version as number, e.g., (9) for version 1.9. | 18| **`CIVETWEB_VERSION_PATCH`** | The current patch version as number, e.g., (0) for version 1.9 or (1) for version 1.9.1. | 19 20## Handles 21 22* `struct mg_context *` 23Handle for one instance of the HTTP(S) server. 24All functions using `const struct mg_context *` as an argument do not modify a running server instance, but just query information. Functions using a non-const `struct mg_context *` as an argument may modify a server instance (e.g., register a new URI, stop the server, ...). 25 26* `struct mg_connection *` 27Handle for one individual client-server connection. 28Functions working with `const struct mg_connection *` operate on data already known to the server without reading data from or sending data to the client. Callbacks using a `const struct mg_connection *` argument are supposed to not call functions from the `mg_read()` and `mg_write()` family. To support a correct application, reading and writing functions require a non-const `struct mg_connection *` connection handle. 29 30The content of both structures is not defined in the interface - they are only used as opaque pointers (handles). 31 32## Structures 33 34* [`struct mg_client_cert;`](api/mg_client_cert.md) 35* [`struct mg_client_options;`](api/mg_client_options.md) 36* [`struct mg_callbacks;`](api/mg_callbacks.md) 37* [`struct mg_form_data_handler;`](api/mg_form_data_handler.md) 38* [`struct mg_header;`](api/mg_header.md) 39* [`struct mg_option;`](api/mg_option.md) 40* [`struct mg_request_info;`](api/mg_request_info.md) 41* [`struct mg_response_info;`](api/mg_response_info.md) 42* [`struct mg_server_port;`](api/mg_server_port.md) 43 44 45## Library API Functions 46 47* [`mg_init_library( feature );`](api/mg_init_library.md) 48* [`mg_exit_library( feature );`](api/mg_exit_library.md) 49 50* [`mg_check_feature( feature );`](api/mg_check_feature.md) 51* [`mg_version();`](api/mg_version.md) 52 53 54## Server API Functions 55 56* [`mg_start( callbacks, user_data, options );`](api/mg_start.md) 57* [`mg_stop( ctx );`](api/mg_stop.md) 58 59* [`mg_get_builtin_mime_type( file_name );`](api/mg_get_builtin_mime_type.md) 60* [`mg_get_option( ctx, name );`](api/mg_get_option.md) 61* [`mg_get_server_ports( ctx, size, ports );`](api/mg_get_server_ports.md) 62* [`mg_get_user_data( ctx );`](api/mg_get_user_data.md) 63* [`mg_set_auth_handler( ctx, uri, handler, cbdata );`](api/mg_set_auth_handler.md) 64* [`mg_set_request_handler( ctx, uri, handler, cbdata );`](api/mg_set_request_handler.md) 65* [`mg_set_websocket_handler( ctx, uri, connect_handler, ready_handler, data_handler, close_handler, cbdata );`](api/mg_set_websocket_handler.md) 66 67* [`mg_lock_context( ctx );`](api/mg_lock_context.md) 68* [`mg_unlock_context( ctx );`](api/mg_unlock_context.md) 69 70* [`mg_get_context( conn );`](api/mg_get_context.md) 71 72* [`mg_send_http_error( conn, status_code, fmt, ... );`](api/mg_send_http_error.md) 73* [`mg_send_http_ok( conn, mime_type, content_length );`](api/mg_send_http_ok.md) 74* [`mg_send_http_redirect( conn, target_url, redirect_code );`](api/mg_send_http_redirect.md) 75 76* [`mg_send_digest_access_authentication_request( conn, realm );`](api/mg_send_digest_access_authentication_request.md) 77* [`mg_check_digest_access_authentication( conn, realm, filename );`](api/mg_check_digest_access_authentication.md) 78* [`mg_modify_passwords_file( passwords_file_name, realm, user, password );`](api/mg_modify_passwords_file.md) 79 80* [`mg_get_request_info( conn );`](api/mg_get_request_info.md) 81* [`mg_get_request_link( conn, buf, buflen );`](api/mg_get_request_link.md) 82* [`mg_handle_form_request( conn, fdh );`](api/mg_handle_form_request.md) 83 84* [`mg_send_file( conn, path );`](api/mg_send_file.md) 85* [`mg_send_mime_file( conn, path, mime_type );`](api/mg_send_mime_file.md) 86* [`mg_send_mime_file2( conn, path, mime_type, additional_headers );`](api/mg_send_mime_file2.md) 87* [`mg_websocket_write( conn, opcode, data, data_len );`](api/mg_websocket_write.md) 88 89## Client API Functions 90 91* [`mg_connect_client( host, port, use_ssl, error_buffer, error_buffer_size );`](api/mg_connect_client.md) 92* [`mg_connect_client_secure( client_options, error_buffer, error_buffer_size );`](api/mg_connect_client_secure.md) 93* [`mg_connect_websocket_client( host, port, use_ssl, error_buffer, error_buffer_size, path, origin, data_func, close_func, user_data);`](api/mg_connect_websocket_client.md) 94* [`mg_websocket_client_write( conn, opcode, data, data_len );`](api/mg_websocket_client_write.md) 95 96* [`mg_download( host, port, use_ssl, error_buffer, error_buffer_size, fmt, ... );`](api/mg_download.md) 97 98* [`mg_get_response( conn, ebuf, ebuf_len, timeout );`](api/mg_get_response.md) 99* [`mg_get_response_info( conn );`](api/mg_get_response_info.md) 100 101## Common API Functions 102 103* [`mg_close_connection( conn );`](api/mg_close_connection.md) 104* [`mg_cry( conn, fmt, ... );`](api/mg_cry.md) 105 106* [`mg_get_cookie( cookie, var_name, buf, buf_len );`](api/mg_get_cookie.md) 107* [`mg_get_header( conn, name );`](api/mg_get_header.md) 108* [`mg_get_response_code_text( conn, response_code );`](api/mg_get_response_code_text.md) 109* [`mg_get_user_connection_data( conn );`](api/mg_get_user_connection_data.md) 110* [`mg_get_valid_options();`](api/mg_get_valid_options.md) 111* [`mg_get_var( data, data_len, var_name, dst, dst_len );`](api/mg_get_var.md) 112* [`mg_get_var2( data, data_len, var_name, dst, dst_len, occurrence );`](api/mg_get_var2.md) 113* [`mg_lock_connection( conn );`](api/mg_lock_connection.md) 114* [`mg_md5( buf, ... );`](api/mg_md5.md) 115* [`mg_printf( conn, fmt, ... );`](api/mg_printf.md) 116* [`mg_read( conn, buf, len );`](api/mg_read.md) 117* [`mg_send_chunk( conn, buf, len );`](api/mg_send_chunk.md) 118* [`mg_send_file( conn, path );`](api/mg_send_file_body.md) 119* [`mg_set_user_connection_data( conn, data );`](api/mg_set_user_connection_data.md) 120* [`mg_start_thread( f, p );`](api/mg_start_thread.md) 121* [`mg_store_body( conn, path );`](api/mg_store_body.md) 122* [`mg_strcasecmp( s1, s2 );`](api/mg_strcasecmp.md) 123* [`mg_strncasecmp( s1, s2, len );`](api/mg_strncasecmp.md) 124* [`mg_unlock_connection( conn );`](api/mg_unlock_connection.md) 125* [`mg_url_decode( src, src_len, dst, dst_len, is_form_url_encoded );`](api/mg_url_decode.md) 126* [`mg_url_encode( src, dst, dst_len );`](api/mg_url_encode.md) 127* [`mg_write( conn, buf, len );`](api/mg_write.md) 128 129 130## Diagnosis Functions 131 132* [`mg_get_system_info( buffer, buf_len );`](api/mg_get_system_info.md) 133* [`mg_get_context_info( ctx, buffer, buf_len );`](api/mg_get_context_info.md) 134* [`mg_get_connection_info( ctx, idx, buffer, buf_len );`](api/mg_get_connection_info.md) 135 136 137## Deprecated: 138 139* [~~`mg_get_valid_option_names();`~~](api/mg_get_valid_option_names.md) 140* [~~`mg_upload( conn, destination_dir );`~~](api/mg_upload.md) 141* [~~`mg_get_ports( ctx, size, ports, ssl);`~~](api/mg_get_ports.md) 142 143 144