Mongoose 6.10

PUBLISHED_FROM=c61fa89018f8cef4f798e094acff8d36c72869f2
Fix MQTT SUBSCRIBE parsing
2026-10-26 12:14:56 +00:00 · 2017-10-31 10:01:27 +00:00 · 2017-10-30 15:34:22 +00:00 · 2017-10-30 14:20:27 +00:00 · 2017-10-24 07:19:45 +00:00 · 2017-10-21 09:19:42 +00:00
585 changed files with 67860 additions and 8065 deletions
@@ -0,0 +1,9 @@
+binary/
+deps/
+docker/
+docs/
+examples/
+platforms/
+src/
+test/
+multilingual/
@@ -0,0 +1,8 @@
+People who have agreed to the
+[Cesanta CLA](https://docs.cesanta.com/contributors_la.shtml)
+can make contributions. Note that the CLA isn't a copyright
+_assigment_ but rather a copyright _license_.
+You retain the copyright on your contributions.
+
+We follow the Google C/C++ style guide: https://google.github.io/styleguide/cppguide.html
+We'd appreciate if your contribution follows the same style guide.
@@ -1,5 +1,5 @@
 Copyright (c) 2004-2013 Sergey Lyubka <valenok@gmail.com>
-Copyright (c) 2013-2015 Cesanta Software Limited
+Copyright (c) 2013-2016 Cesanta Software Limited
 All rights reserved

 This software is dual-licensed: you can redistribute it and/or modify
@@ -1,53 +1,53 @@
-# <img src="http://www.cesanta.com/hubfs/www.cesanta.com/Images/mongoose_library.png" width="64" height="64"> Mongoose - Embedded Web Server
-
-[![Join the chat at https://gitter.im/cesanta/mongoose](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/cesanta/mongoose?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
+# Mongoose - Embedded Web Server / Embedded Networking Library

 ![](https://img.shields.io/badge/license-GPL_2-green.svg "License")

+Mongoose is ideal for embedded environments. It has been designed
+for connecting devices and bringing them online. On the market since 2004,
+used by vast number of open source and
+commercial products - it even runs on the International Space station!
+Mongoose makes embedded network programming fast, robust, and easy.

-Mongoose is ideal for embedded environments, it has been designed as an open
-source platform for connecting devices and bringing them online.
-[Mongoose](https://www.cesanta.com/products)
-has been on the market since 2004 and attracted
-over 1 million cumulative downloads.
+- [Download Mongoose Source Code here](https://www.cesanta.com/download.html)

-It provides easy to use event-driven interface that allows to implement
-network protocols or scalable network applications  with little effort.
-Mongoose helps developers to manage the complexity of network programming
-and let them concentrate on the logic, saving time and money.
+Looking for a complete IoT firmware solution?

-[Download Mongoose Source Code here](http://hubs.ly/H0150FK0)
-
-> Nothing overdone. Nothing less. So unbelievably easy to use.
-> Just how good software should be!
-> - Pritin Tyagaraj, SAP
+Check out [Mongoose OS](https://mongoose-os.com) - open source embedded operating system for low-power connected microcontrollers. Secure, designed for Internet of Things, complete environment for prototyping, development and managing.

+# Support
+- [Study mongoose example code](https://github.com/cesanta/mongoose/tree/master/examples)
+- [Read User Guide and API reference](https://docs.cesanta.com/mongoose)
+- [Support Forum - ask your technical questions here](https://forum.mongoose-os.com/categories/mongoose)
+- [Commercial licensing and support available](https://www.cesanta.com/licensing.html)
+- [Check our latest releases](https://github.com/cesanta/mongoose/releases)

 # Features

-* Cross-platform: works on Linux/UNIX, QNX, eCos, Windows, Android, iPhone, etc
-* Single-threaded, asynchronous, non-blocking core with simple event-based API
+* Cross-platform: works on Linux/UNIX, MacOS, QNX, eCos, Windows, Android,
+  iPhone, FreeRTOS (TI CC3200, ESP8266), etc
+* Supported hardware platforms: TI CC3200, TI MSP432, NRF52, STM32, PIC32, ESP8266, ESP32 and more
 * Builtin protocols:
   - plain TCP, plain UDP, SSL/TLS (over TCP, one-way or two-way)
   - HTTP client, HTTP server
-   - Websocket client, Websocket server
-   - JSON-RPC client, JSON-RPC server
+   - WebSocket client, WebSocket server
   - MQTT client, MQTT broker
   - CoAP client, CoAP server
   - DNS client, DNS server, async DNS resolver
+* Single-threaded, asynchronous, non-blocking core with simple event-based API
+* Native support for [PicoTCP embedded TCP/IP stack](http://www.picotcp.com),
+  [LWIP embedded TCP/IP stack](https://en.wikipedia.org/wiki/LwIP)
 * Tiny static and run-time footprint
 * Source code is both ISO C and ISO C++ compliant
 * Very easy to integrate: just copy
  [mongoose.c](https://raw.githubusercontent.com/cesanta/mongoose/master/mongoose.c) and
  [mongoose.h](https://raw.githubusercontent.com/cesanta/mongoose/master/mongoose.h)
  files to your build tree
-* Extensively tested and production-ready, trusted by many blue chip businesses

-# Examples & Documentation
+# Licensing

- [User Guide](https://docs.cesanta.com/mongoose) - Detailed User Guide and API reference
- [examples](examples) - Collection of well-commented examples. To build any example,
-go into respective directory and type `make`
+Mongoose is released under Commercial and [GNU GPL v.2](http://www.gnu.org/licenses/old-licenses/gpl-2.0.html) open source licenses.
+
+Commercial Projects: [Contact us for commercial license.](https://www.cesanta.com/contact.html)

 # Dashboard Example

@@ -55,47 +55,14 @@ Mongoose is often used to implement device dashboards and real-time
 data exchange over Websocket. Here is a dashboard example that illustrates
 the functionality:

-![](http://www.cesanta.com/hubfs/www.cesanta.com/diagrams/dash_mongoose_diagram.png)
+![](http://www.cesanta.com/images/dashboard.png)

-[Developing a new product? Contact us today to discuss how Mongoose can help
-](https://www.cesanta.com/contact)
+[Developing a new product? Contact us today to discuss how Mongoose can help.](https://www.cesanta.com/contact.html)

+# Contributions

-# Licensing
+To submit contributions, sign [Cesanta CLA](https://cesanta.com/cla.html)
+and send GitHub pull request. You retain the copyright on your contributions.

-You are using Mongoose under
-[GPLv2](http://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html)
-and until you commercialize your
-application, can continue to use Mongoose free of charge.
-
-Once you commercialize your product, in order to comply with GPLv2
-you need to either open the source code of your product fully or
-alternatively purchase a commercial license.
-We offer [three levels of commercial licensing](https://www.cesanta.com/products):
-
- Mongoose Lite: cross platform integration, SSL/TLS, HTTP support
- Mongoose: Mongoose Lite + HTTP CGI, HTTP SSI, HTTP Digest Auth,
-  WebSocket support
- Mongoose Premium: Mongoose + Plain TCP, UDP, JSON-RPC, MQTT, DNS,
-  CoAP support
-
-
-[Enquire about commercial licensing here](https://www.cesanta.com/contact)
-
-# Mongoose Binary
-
-This is our easy to use web server for web developers (PHP, Ruby, Python, etc)
-and web designers. Available in three editions to suit your needs: free, pro
-(USD 5) and dev edition (from USD 8). To install, simply download, double-click
-to start and run browser - that's all!
-
-[Download Mongoose Binary here](https://www.cesanta.com/mongoose)
-
-# Other products by Cesanta
-
- [Smart.js](https://github.com/cesanta/smart.js) -
-    Generic, hardware independent, full-stack IoT software platform
- [V7](https://github.com/cesanta/v7) - Embedded JavaScript engine
- [Frozen](https://github.com/cesanta/frozen) - JSON parser and generator
- [SLRE](https://github.com/cesanta/slre) - Super Light Regular Expression
-  library
+# Looking for a pre-compiled Mongoose web server Windows or Mac binary?
+- [Download pre-compiled Mongoose web server binary.](https://www.cesanta.com/binary.html)
@@ -0,0 +1,26 @@
+---
+title: "CoAP API reference"
+symbol_kind: "intro"
+decl_name: "coap.h"
+items:
+  - { name: mg_coap_add_option.md }
+  - { name: mg_coap_compose.md }
+  - { name: mg_coap_free_options.md }
+  - { name: mg_coap_parse.md }
+  - { name: mg_coap_send_ack.md }
+  - { name: mg_coap_send_message.md }
+  - { name: mg_set_protocol_coap.md }
+  - { name: struct_mg_coap_message.md }
+  - { name: struct_mg_coap_option.md }
+---
+
+CoAP message format:
+
+```
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
+|Ver| T | TKL | Code | Message ID | Token (if any, TKL bytes) ...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
+| Options (if any) ...            |1 1 1 1 1 1 1 1| Payload (if any) ...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
+```
+
@@ -0,0 +1,14 @@
+---
+title: "mg_coap_add_option()"
+decl_name: "mg_coap_add_option"
+symbol_kind: "func"
+signature: |
+  struct mg_coap_option *mg_coap_add_option(struct mg_coap_message *cm,
+                                            uint32_t number, char *value,
+                                            size_t len);
+---
+
+Adds a new option to mg_coap_message structure.
+Returns pointer to the newly created option.
+Note: options must be freed by using mg_coap_free_options 
+
@@ -0,0 +1,12 @@
+---
+title: "mg_coap_compose()"
+decl_name: "mg_coap_compose"
+symbol_kind: "func"
+signature: |
+  uint32_t mg_coap_compose(struct mg_coap_message *cm, struct mbuf *io);
+---
+
+Composes CoAP message from mg_coap_message structure.
+This is a helper function.
+Return value: see `mg_coap_send_message()` 
+
@@ -0,0 +1,11 @@
+---
+title: "mg_coap_free_options()"
+decl_name: "mg_coap_free_options"
+symbol_kind: "func"
+signature: |
+  void mg_coap_free_options(struct mg_coap_message *cm);
+---
+
+Frees the memory allocated for options.
+If the cm parameter doesn't contain any option it does nothing. 
+
@@ -0,0 +1,22 @@
+---
+title: "mg_coap_parse()"
+decl_name: "mg_coap_parse"
+symbol_kind: "func"
+signature: |
+  uint32_t mg_coap_parse(struct mbuf *io, struct mg_coap_message *cm);
+---
+
+Parses CoAP message and fills mg_coap_message and returns cm->flags.
+This is a helper function.
+
+NOTE: usually CoAP works over UDP, so lack of data means format error.
+But, in theory, it is possible to use CoAP over TCP (according to RFC)
+
+The caller has to check results and treat COAP_NOT_ENOUGH_DATA according to
+underlying protocol:
+
+- in case of UDP COAP_NOT_ENOUGH_DATA means COAP_FORMAT_ERROR,
+- in case of TCP client can try to receive more data
+
+Return value: see `mg_coap_send_message()` 
+
@@ -0,0 +1,12 @@
+---
+title: "mg_coap_send_ack()"
+decl_name: "mg_coap_send_ack"
+symbol_kind: "func"
+signature: |
+  uint32_t mg_coap_send_ack(struct mg_connection *nc, uint16_t msg_id);
+---
+
+Composes CoAP acknowledgement from `mg_coap_message`
+and sends it into `nc` connection.
+Return value: see `mg_coap_send_message()` 
+
@@ -0,0 +1,19 @@
+---
+title: "mg_coap_send_message()"
+decl_name: "mg_coap_send_message"
+symbol_kind: "func"
+signature: |
+  uint32_t mg_coap_send_message(struct mg_connection *nc,
+                                struct mg_coap_message *cm);
+---
+
+Composes a CoAP message from `mg_coap_message`
+and sends it into `nc` connection.
+Returns 0 on success. On error, it is a bitmask:
+
+- `#define MG_COAP_ERROR 0x10000`
+- `#define MG_COAP_FORMAT_ERROR (MG_COAP_ERROR | 0x20000)`
+- `#define MG_COAP_IGNORE (MG_COAP_ERROR | 0x40000)`
+- `#define MG_COAP_NOT_ENOUGH_DATA (MG_COAP_ERROR | 0x80000)`
+- `#define MG_COAP_NETWORK_ERROR (MG_COAP_ERROR | 0x100000)` 
+
@@ -0,0 +1,10 @@
+---
+title: "mg_set_protocol_coap()"
+decl_name: "mg_set_protocol_coap"
+symbol_kind: "func"
+signature: |
+  int mg_set_protocol_coap(struct mg_connection *nc);
+---
+
+Sets CoAP protocol handler - triggers CoAP specific events. 
+
@@ -0,0 +1,20 @@
+---
+title: "struct mg_coap_message"
+decl_name: "struct mg_coap_message"
+symbol_kind: "struct"
+signature: |
+  struct mg_coap_message {
+    uint32_t flags;
+    uint8_t msg_type;
+    uint8_t code_class;
+    uint8_t code_detail;
+    uint16_t msg_id;
+    struct mg_str token;
+    struct mg_coap_option *options;
+    struct mg_str payload;
+    struct mg_coap_option *optiomg_tail;
+  };
+---
+
+CoAP message. See RFC 7252 for details. 
+
@@ -0,0 +1,16 @@
+---
+title: "struct mg_coap_option"
+decl_name: "struct mg_coap_option"
+symbol_kind: "struct"
+signature: |
+  struct mg_coap_option {
+    struct mg_coap_option *next;
+    uint32_t number;
+    struct mg_str value;
+  };
+---
+
+CoAP options.
+Use mg_coap_add_option and mg_coap_free_options
+for creation and destruction. 
+
@@ -0,0 +1,20 @@
+---
+title: "DNS API reference"
+symbol_kind: "intro"
+decl_name: "dns.h"
+items:
+  - { name: mg_dns_copy_questions.md }
+  - { name: mg_dns_encode_name.md }
+  - { name: mg_dns_encode_record.md }
+  - { name: mg_dns_insert_header.md }
+  - { name: mg_dns_parse_record_data.md }
+  - { name: mg_dns_uncompress_name.md }
+  - { name: mg_parse_dns.md }
+  - { name: mg_send_dns_query.md }
+  - { name: mg_set_protocol_dns.md }
+  - { name: struct_mg_dns_message.md }
+  - { name: struct_mg_dns_resource_record.md }
+---
+
+
+
@@ -0,0 +1,15 @@
+---
+title: "mg_dns_copy_questions()"
+decl_name: "mg_dns_copy_questions"
+symbol_kind: "func"
+signature: |
+  int mg_dns_copy_questions(struct mbuf *io, struct mg_dns_message *msg);
+---
+
+Appends already encoded questions from an existing message.
+
+This is useful when generating a DNS reply message which includes
+all question records.
+
+Returns the number of appended bytes. 
+
@@ -0,0 +1,10 @@
+---
+title: "mg_dns_encode_name()"
+decl_name: "mg_dns_encode_name"
+symbol_kind: "func"
+signature: |
+  int mg_dns_encode_name(struct mbuf *io, const char *name, size_t len);
+---
+
+Encodes a DNS name. 
+
@@ -0,0 +1,25 @@
+---
+title: "mg_dns_encode_record()"
+decl_name: "mg_dns_encode_record"
+symbol_kind: "func"
+signature: |
+  int mg_dns_encode_record(struct mbuf *io, struct mg_dns_resource_record *rr,
+                           const char *name, size_t nlen, const void *rdata,
+                           size_t rlen);
+---
+
+Encodes and appends a DNS resource record to an IO buffer.
+
+The record metadata is taken from the `rr` parameter, while the name and data
+are taken from the parameters, encoded in the appropriate format depending on
+record type and stored in the IO buffer. The encoded values might contain
+offsets within the IO buffer. It's thus important that the IO buffer doesn't
+get trimmed while a sequence of records are encoded while preparing a DNS
+reply.
+
+This function doesn't update the `name` and `rdata` pointers in the `rr`
+struct because they might be invalidated as soon as the IO buffer grows
+again.
+
+Returns the number of bytes appended or -1 in case of error. 
+
@@ -0,0 +1,13 @@
+---
+title: "mg_dns_insert_header()"
+decl_name: "mg_dns_insert_header"
+symbol_kind: "func"
+signature: |
+  int mg_dns_insert_header(struct mbuf *io, size_t pos,
+                           struct mg_dns_message *msg);
+---
+
+Inserts a DNS header to an IO buffer.
+
+Returns the number of bytes inserted. 
+
@@ -0,0 +1,20 @@
+---
+title: "mg_dns_parse_record_data()"
+decl_name: "mg_dns_parse_record_data"
+symbol_kind: "func"
+signature: |
+  int mg_dns_parse_record_data(struct mg_dns_message *msg,
+                               struct mg_dns_resource_record *rr, void *data,
+                               size_t data_len);
+---
+
+Parses the record data from a DNS resource record.
+
+ - A:     struct in_addr *ina
+ - AAAA:  struct in6_addr *ina
+ - CNAME: char buffer
+
+Returns -1 on error.
+
+TODO(mkm): MX 
+
@@ -0,0 +1,21 @@
+---
+title: "mg_dns_uncompress_name()"
+decl_name: "mg_dns_uncompress_name"
+symbol_kind: "func"
+signature: |
+  size_t mg_dns_uncompress_name(struct mg_dns_message *msg, struct mg_str *name,
+                                char *dst, int dst_len);
+---
+
+Uncompresses a DNS compressed name.
+
+The containing DNS message is required because of the compressed encoding
+and reference suffixes present elsewhere in the packet.
+
+If the name is less than `dst_len` characters long, the remainder
+of `dst` is terminated with `\0` characters. Otherwise, `dst` is not
+terminated.
+
+If `dst_len` is 0 `dst` can be NULL.
+Returns the uncompressed name length. 
+
@@ -0,0 +1,10 @@
+---
+title: "mg_parse_dns()"
+decl_name: "mg_parse_dns"
+symbol_kind: "func"
+signature: |
+  int mg_parse_dns(const char *buf, int len, struct mg_dns_message *msg);
+---
+
+Low-level: parses a DNS response. 
+
@@ -0,0 +1,11 @@
+---
+title: "mg_send_dns_query()"
+decl_name: "mg_send_dns_query"
+symbol_kind: "func"
+signature: |
+  void mg_send_dns_query(struct mg_connection *nc, const char *name,
+                         int query_type);
+---
+
+Sends a DNS query to the remote end. 
+
@@ -0,0 +1,19 @@
+---
+title: "mg_set_protocol_dns()"
+decl_name: "mg_set_protocol_dns"
+symbol_kind: "func"
+signature: |
+  void mg_set_protocol_dns(struct mg_connection *nc);
+---
+
+Attaches a built-in DNS event handler to the given listening connection.
+
+The DNS event handler parses the incoming UDP packets, treating them as DNS
+requests. If an incoming packet gets successfully parsed by the DNS event
+handler, a user event handler will receive an `MG_DNS_REQUEST` event, with
+`ev_data` pointing to the parsed `struct mg_dns_message`.
+
+See
+[captive_dns_server](https://github.com/cesanta/mongoose/tree/master/examples/captive_dns_server)
+example on how to handle DNS request and send DNS reply. 
+
@@ -0,0 +1,18 @@
+---
+title: "struct mg_dns_message"
+decl_name: "struct mg_dns_message"
+symbol_kind: "struct"
+signature: |
+  struct mg_dns_message {
+    struct mg_str pkt; /* packet body */
+    uint16_t flags;
+    uint16_t transaction_id;
+    int num_questions;
+    int num_answers;
+    struct mg_dns_resource_record questions[MG_MAX_DNS_QUESTIONS];
+    struct mg_dns_resource_record answers[MG_MAX_DNS_ANSWERS];
+  };
+---
+
+DNS message (request and response). 
+
@@ -0,0 +1,17 @@
+---
+title: "struct mg_dns_resource_record"
+decl_name: "struct mg_dns_resource_record"
+symbol_kind: "struct"
+signature: |
+  struct mg_dns_resource_record {
+    struct mg_str name; /* buffer with compressed name */
+    int rtype;
+    int rclass;
+    int ttl;
+    enum mg_dns_resource_record_kind kind;
+    struct mg_str rdata; /* protocol data (can be a compressed name) */
+  };
+---
+
+DNS resource record. 
+
@@ -0,0 +1,12 @@
+---
+title: "DNS server API reference"
+symbol_kind: "intro"
+decl_name: "dns_server.h"
+items:
+  - { name: mg_dns_create_reply.md }
+  - { name: mg_dns_reply_record.md }
+  - { name: mg_dns_send_reply.md }
+---
+
+Disabled by default; enable with `-DMG_ENABLE_DNS_SERVER`.
+
@@ -0,0 +1,36 @@
+---
+title: "mg_dns_create_reply()"
+decl_name: "mg_dns_create_reply"
+symbol_kind: "func"
+signature: |
+  struct mg_dns_reply mg_dns_create_reply(struct mbuf *io,
+                                          struct mg_dns_message *msg);
+---
+
+Creates a DNS reply.
+
+The reply will be based on an existing query message `msg`.
+The query body will be appended to the output buffer.
+"reply + recursion allowed" will be added to the message flags and the
+message's num_answers will be set to 0.
+
+Answer records can be appended with `mg_dns_send_reply` or by lower
+level function defined in the DNS API.
+
+In order to send a reply use `mg_dns_send_reply`.
+It's possible to use a connection's send buffer as reply buffer,
+and it will work for both UDP and TCP connections.
+
+Example:
+
+```c
+reply = mg_dns_create_reply(&nc->send_mbuf, msg);
+for (i = 0; i < msg->num_questions; i++) {
+  rr = &msg->questions[i];
+  if (rr->rtype == MG_DNS_A_RECORD) {
+    mg_dns_reply_record(&reply, rr, 3600, &dummy_ip_addr, 4);
+  }
+}
+mg_dns_send_reply(nc, &reply);
+``` 
+
@@ -0,0 +1,18 @@
+---
+title: "mg_dns_reply_record()"
+decl_name: "mg_dns_reply_record"
+symbol_kind: "func"
+signature: |
+  int mg_dns_reply_record(struct mg_dns_reply *reply,
+                          struct mg_dns_resource_record *question,
+                          const char *name, int rtype, int ttl, const void *rdata,
+                          size_t rdata_len);
+---
+
+Appends a DNS reply record to the IO buffer and to the DNS message.
+
+The message's num_answers field will be incremented. It's the caller's duty
+to ensure num_answers is properly initialised.
+
+Returns -1 on error. 
+
@@ -0,0 +1,19 @@
+---
+title: "mg_dns_send_reply()"
+decl_name: "mg_dns_send_reply"
+symbol_kind: "func"
+signature: |
+  void mg_dns_send_reply(struct mg_connection *nc, struct mg_dns_reply *r);
+---
+
+Sends a DNS reply through a connection.
+
+The DNS data is stored in an IO buffer pointed by reply structure in `r`.
+This function mutates the content of that buffer in order to ensure that
+the DNS header reflects the size and flags of the message, that might have
+been updated either with `mg_dns_reply_record` or by direct manipulation of
+`r->message`.
+
+Once sent, the IO buffer will be trimmed unless the reply IO buffer
+is the connection's send buffer and the connection is not in UDP mode. 
+
@@ -0,0 +1,24 @@
+---
+title: "Common API reference"
+symbol_kind: "intro"
+decl_name: "http.h"
+items:
+  - { name: mg_connect_ws.md }
+  - { name: mg_connect_ws_opt.md }
+  - { name: mg_printf_websocket_frame.md }
+  - { name: mg_send_websocket_frame.md }
+  - { name: mg_send_websocket_framev.md }
+  - { name: mg_send_websocket_handshake.md }
+  - { name: mg_send_websocket_handshake2.md }
+  - { name: mg_send_websocket_handshake3.md }
+  - { name: mg_send_websocket_handshake3v.md }
+  - { name: mg_set_protocol_http_websocket.md }
+  - { name: mg_url_decode.md }
+  - { name: struct_http_message.md }
+  - { name: struct_mg_http_multipart_part.md }
+  - { name: struct_mg_ssi_call_ctx.md }
+  - { name: struct_websocket_message.md }
+---
+
+
+
@@ -0,0 +1,29 @@
+---
+title: "mg_connect_ws()"
+decl_name: "mg_connect_ws"
+symbol_kind: "func"
+signature: |
+  struct mg_connection *mg_connect_ws(struct mg_mgr *mgr,
+                                      MG_CB(mg_event_handler_t event_handler,
+                                            void *user_data);
+---
+
+Helper function that creates an outbound WebSocket connection.
+
+`url` is a URL to connect to. It must be properly URL-encoded, e.g. have
+no spaces, etc. By default, `mg_connect_ws()` sends Connection and
+Host headers. `extra_headers` is an extra HTTP header to send, e.g.
+`"User-Agent: my-app\r\n"`.
+If `protocol` is not NULL, then a `Sec-WebSocket-Protocol` header is sent.
+
+Examples:
+
+```c
+  nc1 = mg_connect_ws(mgr, ev_handler_1, "ws://echo.websocket.org", NULL,
+                      NULL);
+  nc2 = mg_connect_ws(mgr, ev_handler_1, "wss://echo.websocket.org", NULL,
+                      NULL);
+  nc3 = mg_connect_ws(mgr, ev_handler_1, "ws://api.cesanta.com",
+                      "clubby.cesanta.com", NULL);
+``` 
+
@@ -0,0 +1,14 @@
+---
+title: "mg_connect_ws_opt()"
+decl_name: "mg_connect_ws_opt"
+symbol_kind: "func"
+signature: |
+  struct mg_connection *mg_connect_ws_opt(
+      struct mg_mgr *mgr, MG_CB(mg_event_handler_t ev_handler, void *user_data);
+---
+
+Helper function that creates an outbound WebSocket connection
+
+Mostly identical to `mg_connect_ws`, but allows to provide extra parameters
+(for example, SSL parameters) 
+
@@ -0,0 +1,14 @@
+---
+title: "mg_printf_websocket_frame()"
+decl_name: "mg_printf_websocket_frame"
+symbol_kind: "func"
+signature: |
+  void mg_printf_websocket_frame(struct mg_connection *nc, int op_and_flags,
+                                 const char *fmt, ...);
+---
+
+Sends WebSocket frame to the remote end.
+
+Like `mg_send_websocket_frame()`, but allows to create formatted messages
+with `printf()`-like semantics. 
+
@@ -0,0 +1,26 @@
+---
+title: "mg_send_websocket_frame()"
+decl_name: "mg_send_websocket_frame"
+symbol_kind: "func"
+signature: |
+  void mg_send_websocket_frame(struct mg_connection *nc, int op_and_flags,
+                               const void *data, size_t data_len);
+---
+
+Send WebSocket frame to the remote end.
+
+`op_and_flags` specifies the frame's type. It's one of:
+
+- WEBSOCKET_OP_CONTINUE
+- WEBSOCKET_OP_TEXT
+- WEBSOCKET_OP_BINARY
+- WEBSOCKET_OP_CLOSE
+- WEBSOCKET_OP_PING
+- WEBSOCKET_OP_PONG
+
+Orred with one of the flags:
+
+- WEBSOCKET_DONT_FIN: Don't set the FIN flag on the frame to be sent.
+
+`data` and `data_len` contain frame data. 
+
@@ -0,0 +1,14 @@
+---
+title: "mg_send_websocket_framev()"
+decl_name: "mg_send_websocket_framev"
+symbol_kind: "func"
+signature: |
+  void mg_send_websocket_framev(struct mg_connection *nc, int op_and_flags,
+                                const struct mg_str *strings, int num_strings);
+---
+
+Sends multiple websocket frames.
+
+Like `mg_send_websocket_frame()`, but composes a frame from multiple
+*buffers. 
+
@@ -0,0 +1,22 @@
+---
+title: "mg_send_websocket_handshake()"
+decl_name: "mg_send_websocket_handshake"
+symbol_kind: "func"
+signature: |
+  void mg_send_websocket_handshake(struct mg_connection *nc, const char *uri,
+                                   const char *extra_headers);
+---
+
+Send websocket handshake to the server.
+
+`nc` must be a valid connection, connected to a server. `uri` is an URI
+to fetch, extra_headers` is extra HTTP headers to send or `NULL`.
+
+This function is intended to be used by websocket client.
+
+Note that the Host header is mandatory in HTTP/1.1 and must be
+included in `extra_headers`. `mg_send_websocket_handshake2` offers
+a better API for that.
+
+Deprecated in favour of `mg_send_websocket_handshake2` 
+
@@ -0,0 +1,19 @@
+---
+title: "mg_send_websocket_handshake2()"
+decl_name: "mg_send_websocket_handshake2"
+symbol_kind: "func"
+signature: |
+  void mg_send_websocket_handshake2(struct mg_connection *nc, const char *path,
+                                    const char *host, const char *protocol,
+                                    const char *extra_headers);
+---
+
+Send websocket handshake to the server.
+
+`nc` must be a valid connection, connected to a server. `uri` is an URI
+to fetch, `host` goes into the `Host` header, `protocol` goes into the
+`Sec-WebSocket-Proto` header (NULL to omit), extra_headers` is extra HTTP
+headers to send or `NULL`.
+
+This function is intended to be used by websocket client. 
+
@@ -0,0 +1,13 @@
+---
+title: "mg_send_websocket_handshake3()"
+decl_name: "mg_send_websocket_handshake3"
+symbol_kind: "func"
+signature: |
+  void mg_send_websocket_handshake3(struct mg_connection *nc, const char *path,
+                                    const char *host, const char *protocol,
+                                    const char *extra_headers, const char *user,
+                                    const char *pass);
+---
+
+Like mg_send_websocket_handshake2 but also passes basic auth header 
+
@@ -0,0 +1,17 @@
+---
+title: "mg_send_websocket_handshake3v()"
+decl_name: "mg_send_websocket_handshake3v"
+symbol_kind: "func"
+signature: |
+  void mg_send_websocket_handshake3v(struct mg_connection *nc,
+                                     const struct mg_str path,
+                                     const struct mg_str host,
+                                     const struct mg_str protocol,
+                                     const struct mg_str extra_headers,
+                                     const struct mg_str user,
+                                     const struct mg_str pass);
+---
+
+Same as mg_send_websocket_handshake3 but with strings not necessarily
+NUL-temrinated 
+
@@ -0,0 +1,59 @@
+---
+title: "mg_set_protocol_http_websocket()"
+decl_name: "mg_set_protocol_http_websocket"
+symbol_kind: "func"
+signature: |
+  void mg_set_protocol_http_websocket(struct mg_connection *nc);
+---
+
+Attaches a built-in HTTP event handler to the given connection.
+The user-defined event handler will receive following extra events:
+
+- MG_EV_HTTP_REQUEST: HTTP request has arrived. Parsed HTTP request
+ is passed as
+  `struct http_message` through the handler's `void *ev_data` pointer.
+- MG_EV_HTTP_REPLY: The HTTP reply has arrived. The parsed HTTP reply is
+  passed as `struct http_message` through the handler's `void *ev_data`
+  pointer.
+- MG_EV_HTTP_CHUNK: The HTTP chunked-encoding chunk has arrived.
+  The parsed HTTP reply is passed as `struct http_message` through the
+  handler's `void *ev_data` pointer. `http_message::body` would contain
+  incomplete, reassembled HTTP body.
+  It will grow with every new chunk that arrives, and it can
+  potentially consume a lot of memory. An event handler may process
+  the body as chunks are coming, and signal Mongoose to delete processed
+  body by setting `MG_F_DELETE_CHUNK` in `mg_connection::flags`. When
+  the last zero chunk is received,
+  Mongoose sends `MG_EV_HTTP_REPLY` event with
+  full reassembled body (if handler did not signal to delete chunks) or
+  with empty body (if handler did signal to delete chunks).
+- MG_EV_WEBSOCKET_HANDSHAKE_REQUEST: server has received the WebSocket
+  handshake request. `ev_data` contains parsed HTTP request.
+- MG_EV_WEBSOCKET_HANDSHAKE_DONE: server has completed the WebSocket
+  handshake. `ev_data` is `NULL`.
+- MG_EV_WEBSOCKET_FRAME: new WebSocket frame has arrived. `ev_data` is
+  `struct websocket_message *`
+
+When compiled with MG_ENABLE_HTTP_STREAMING_MULTIPART, Mongoose parses
+multipart requests and splits them into separate events:
+- MG_EV_HTTP_MULTIPART_REQUEST: Start of the request.
+  This event is sent before body is parsed. After this, the user
+  should expect a sequence of PART_BEGIN/DATA/END requests.
+  This is also the last time when headers and other request fields are
+  accessible.
+- MG_EV_HTTP_PART_BEGIN: Start of a part of a multipart message.
+  Argument: mg_http_multipart_part with var_name and file_name set
+  (if present). No data is passed in this message.
+- MG_EV_HTTP_PART_DATA: new portion of data from the multipart message.
+  Argument: mg_http_multipart_part. var_name and file_name are preserved,
+  data is available in mg_http_multipart_part.data.
+- MG_EV_HTTP_PART_END: End of the current part. var_name, file_name are
+  the same, no data in the message. If status is 0, then the part is
+  properly terminated with a boundary, status < 0 means that connection
+  was terminated.
+- MG_EV_HTTP_MULTIPART_REQUEST_END: End of the multipart request.
+  Argument: mg_http_multipart_part, var_name and file_name are NULL,
+  status = 0 means request was properly closed, < 0 means connection
+  was terminated (note: in this case both PART_END and REQUEST_END are
+  delivered). 
+
@@ -0,0 +1,19 @@
+---
+title: "mg_url_decode()"
+decl_name: "mg_url_decode"
+symbol_kind: "func"
+signature: |
+  int mg_url_decode(const char *src, int src_len, char *dst, int dst_len,
+                    int is_form_url_encoded);
+---
+
+Decodes a URL-encoded string.
+
+Source string is specified by (`src`, `src_len`), and destination is
+(`dst`, `dst_len`). If `is_form_url_encoded` is non-zero, then
+`+` character is decoded as a blank space character. This function
+guarantees to NUL-terminate the destination. If destination is too small,
+then the source string is partially decoded and `-1` is returned.
+*Otherwise,
+a length of the decoded string is returned, not counting final NUL. 
+
@@ -0,0 +1,36 @@
+---
+title: "struct http_message"
+decl_name: "struct http_message"
+symbol_kind: "struct"
+signature: |
+  struct http_message {
+    struct mg_str message; /* Whole message: request line + headers + body */
+    struct mg_str body;    /* Message body. 0-length for requests with no body */
+  
+    /* HTTP Request line (or HTTP response line) */
+    struct mg_str method; /* "GET" */
+    struct mg_str uri;    /* "/my_file.html" */
+    struct mg_str proto;  /* "HTTP/1.1" -- for both request and response */
+  
+    /* For responses, code and response status message are set */
+    int resp_code;
+    struct mg_str resp_status_msg;
+  
+    /*
+     * Query-string part of the URI. For example, for HTTP request
+     *    GET /foo/bar?param1=val1&param2=val2
+     *    |    uri    |     query_string     |
+     *
+     * Note that question mark character doesn't belong neither to the uri,
+     * nor to the query_string
+     */
+    struct mg_str query_string;
+  
+    /* Headers */
+    struct mg_str header_names[MG_MAX_HTTP_HEADERS];
+    struct mg_str header_values[MG_MAX_HTTP_HEADERS];
+  };
+---
+
+HTTP message 
+
@@ -0,0 +1,16 @@
+---
+title: "struct mg_http_multipart_part"
+decl_name: "struct mg_http_multipart_part"
+symbol_kind: "struct"
+signature: |
+  struct mg_http_multipart_part {
+    const char *file_name;
+    const char *var_name;
+    struct mg_str data;
+    int status; /* <0 on error */
+    void *user_data;
+  };
+---
+
+HTTP multipart part 
+
@@ -0,0 +1,14 @@
+---
+title: "struct mg_ssi_call_ctx"
+decl_name: "struct mg_ssi_call_ctx"
+symbol_kind: "struct"
+signature: |
+  struct mg_ssi_call_ctx {
+    struct http_message *req; /* The request being processed. */
+    struct mg_str file;       /* Filesystem path of the file being processed. */
+    struct mg_str arg; /* The argument passed to the tag: <!-- call arg -->. */
+  };
+---
+
+SSI call context 
+
@@ -0,0 +1,14 @@
+---
+title: "struct websocket_message"
+decl_name: "struct websocket_message"
+symbol_kind: "struct"
+signature: |
+  struct websocket_message {
+    unsigned char *data;
+    size_t size;
+    unsigned char flags;
+  };
+---
+
+WebSocket message 
+
@@ -0,0 +1,12 @@
+---
+title: "Client API reference"
+symbol_kind: "intro"
+decl_name: "http_client.h"
+items:
+  - { name: mg_connect_http.md }
+  - { name: mg_connect_http_opt.md }
+  - { name: mg_http_create_digest_auth_header.md }
+---
+
+
+
@@ -0,0 +1,33 @@
+---
+title: "mg_connect_http()"
+decl_name: "mg_connect_http"
+symbol_kind: "func"
+signature: |
+  struct mg_connection *mg_connect_http(
+      struct mg_mgr *mgr,
+      MG_CB(mg_event_handler_t event_handler, void *user_data);
+---
+
+Helper function that creates an outbound HTTP connection.
+
+`url` is the URL to fetch. It must be properly URL-encoded, e.g. have
+no spaces, etc. By default, `mg_connect_http()` sends the Connection and
+Host headers. `extra_headers` is an extra HTTP header to send, e.g.
+`"User-Agent: my-app\r\n"`.
+If `post_data` is NULL, then a GET request is created. Otherwise, a POST
+request is created with the specified POST data. Note that if the data being
+posted is a form submission, the `Content-Type` header should be set
+accordingly (see example below).
+
+Examples:
+
+```c
+  nc1 = mg_connect_http(mgr, ev_handler_1, "http://www.google.com", NULL,
+                        NULL);
+  nc2 = mg_connect_http(mgr, ev_handler_1, "https://github.com", NULL, NULL);
+  nc3 = mg_connect_http(
+      mgr, ev_handler_1, "my_server:8000/form_submit/",
+      "Content-Type: application/x-www-form-urlencoded\r\n",
+      "var_1=value_1&var_2=value_2");
+``` 
+
@@ -0,0 +1,15 @@
+---
+title: "mg_connect_http_opt()"
+decl_name: "mg_connect_http_opt"
+symbol_kind: "func"
+signature: |
+  struct mg_connection *mg_connect_http_opt(
+      struct mg_mgr *mgr, MG_CB(mg_event_handler_t ev_handler, void *user_data);
+---
+
+Helper function that creates an outbound HTTP connection.
+
+Mostly identical to mg_connect_http, but allows you to provide extra
+*parameters
+(for example, SSL parameters) 
+
@@ -0,0 +1,13 @@
+---
+title: "mg_http_create_digest_auth_header()"
+decl_name: "mg_http_create_digest_auth_header"
+symbol_kind: "func"
+signature: |
+  int mg_http_create_digest_auth_header(char *buf, size_t buf_len,
+                                        const char *method, const char *uri,
+                                        const char *auth_domain, const char *user,
+                                        const char *passwd);
+---
+
+Creates digest authentication header for a client request. 
+
@@ -0,0 +1,32 @@
+---
+title: "Server API reference"
+symbol_kind: "intro"
+decl_name: "http_server.h"
+items:
+  - { name: mg_check_digest_auth.md }
+  - { name: mg_file_upload_handler.md }
+  - { name: mg_get_http_basic_auth.md }
+  - { name: mg_get_http_header.md }
+  - { name: mg_get_http_var.md }
+  - { name: mg_http_check_digest_auth.md }
+  - { name: mg_http_parse_header.md }
+  - { name: mg_http_reverse_proxy.md }
+  - { name: mg_http_send_error.md }
+  - { name: mg_http_send_redirect.md }
+  - { name: mg_http_serve_file.md }
+  - { name: mg_parse_http.md }
+  - { name: mg_parse_http_basic_auth.md }
+  - { name: mg_parse_multipart.md }
+  - { name: mg_printf_html_escape.md }
+  - { name: mg_printf_http_chunk.md }
+  - { name: mg_register_http_endpoint.md }
+  - { name: mg_send_head.md }
+  - { name: mg_send_http_chunk.md }
+  - { name: mg_send_response_line.md }
+  - { name: mg_serve_http.md }
+  - { name: mg_fu_fname_fn.md }
+  - { name: struct_mg_serve_http_opts.md }
+---
+
+
+
@@ -0,0 +1,17 @@
+---
+title: "mg_check_digest_auth()"
+decl_name: "mg_check_digest_auth"
+symbol_kind: "func"
+signature: |
+  int mg_check_digest_auth(struct mg_str method, struct mg_str uri,
+                           struct mg_str username, struct mg_str cnonce,
+                           struct mg_str response, struct mg_str qop,
+                           struct mg_str nc, struct mg_str nonce,
+                           struct mg_str auth_domain, FILE *fp);
+---
+
+Authenticates given response params against an opened password file.
+Returns 1 if authenticated, 0 otherwise.
+
+It's used by mg_http_check_digest_auth(). 
+
@@ -0,0 +1,41 @@
+---
+title: "mg_file_upload_handler()"
+decl_name: "mg_file_upload_handler"
+symbol_kind: "func"
+signature: |
+  void mg_file_upload_handler(struct mg_connection *nc, int ev, void *ev_data,
+                              mg_fu_fname_fn local_name_fn
+                                  MG_UD_ARG(void *user_data);
+---
+
+File upload handler.
+This handler can be used to implement file uploads with minimum code.
+This handler will process MG_EV_HTTP_PART_* events and store file data into
+a local file.
+`local_name_fn` will be invoked with whatever name was provided by the client
+and will expect the name of the local file to open. A return value of NULL
+will abort file upload (client will get a "403 Forbidden" response). If
+non-null, the returned string must be heap-allocated and will be freed by
+the caller.
+Exception: it is ok to return the same string verbatim.
+
+Example:
+
+```c
+struct mg_str upload_fname(struct mg_connection *nc, struct mg_str fname) {
+  // Just return the same filename. Do not actually do this except in test!
+  // fname is user-controlled and needs to be sanitized.
+  return fname;
+}
+void ev_handler(struct mg_connection *nc, int ev, void *ev_data) {
+  switch (ev) {
+    ...
+    case MG_EV_HTTP_PART_BEGIN:
+    case MG_EV_HTTP_PART_DATA:
+    case MG_EV_HTTP_PART_END:
+      mg_file_upload_handler(nc, ev, ev_data, upload_fname);
+      break;
+  }
+}
+``` 
+
@@ -0,0 +1,11 @@
+---
+title: "mg_fu_fname_fn"
+decl_name: "mg_fu_fname_fn"
+symbol_kind: "typedef"
+signature: |
+  typedef struct mg_str (*mg_fu_fname_fn)(struct mg_connection *nc,
+                                          struct mg_str fname);
+---
+
+Callback prototype for `mg_file_upload_handler()`. 
+
@@ -0,0 +1,14 @@
+---
+title: "mg_get_http_basic_auth()"
+decl_name: "mg_get_http_basic_auth"
+symbol_kind: "func"
+signature: |
+  int mg_get_http_basic_auth(struct http_message *hm, char *user, size_t user_len,
+                             char *pass, size_t pass_len);
+---
+
+Gets and parses the Authorization: Basic header
+Returns -1 if no Authorization header is found, or if
+mg_parse_http_basic_auth
+fails parsing the resulting header. 
+
@@ -0,0 +1,13 @@
+---
+title: "mg_get_http_header()"
+decl_name: "mg_get_http_header"
+symbol_kind: "func"
+signature: |
+  struct mg_str *mg_get_http_header(struct http_message *hm, const char *name);
+---
+
+Searches and returns the header `name` in parsed HTTP message `hm`.
+If header is not found, NULL is returned. Example:
+
+    struct mg_str *host_hdr = mg_get_http_header(hm, "Host"); 
+
@@ -0,0 +1,17 @@
+---
+title: "mg_get_http_var()"
+decl_name: "mg_get_http_var"
+symbol_kind: "func"
+signature: |
+  int mg_get_http_var(const struct mg_str *buf, const char *name, char *dst,
+                      size_t dst_len);
+---
+
+Fetches a HTTP form variable.
+
+Fetches a variable `name` from a `buf` into a buffer specified by `dst`,
+`dst_len`. The destination is always zero-terminated. Returns the length of
+a fetched variable. If not found, 0 is returned. `buf` must be valid
+url-encoded buffer. If destination is too small or an error occured,
+negative number is returned. 
+
@@ -0,0 +1,12 @@
+---
+title: "mg_http_check_digest_auth()"
+decl_name: "mg_http_check_digest_auth"
+symbol_kind: "func"
+signature: |
+  int mg_http_check_digest_auth(struct http_message *hm, const char *auth_domain,
+                                FILE *fp);
+---
+
+Authenticates a HTTP request against an opened password file.
+Returns 1 if authenticated, 0 otherwise. 
+
@@ -0,0 +1,23 @@
+---
+title: "mg_http_parse_header()"
+decl_name: "mg_http_parse_header"
+symbol_kind: "func"
+signature: |
+  int mg_http_parse_header(struct mg_str *hdr, const char *var_name, char *buf,
+                           size_t buf_size);
+---
+
+Parses the HTTP header `hdr`. Finds variable `var_name` and stores its value
+in the buffer `buf`, `buf_size`. Returns 0 if variable not found, non-zero
+otherwise.
+
+This function is supposed to parse cookies, authentication headers, etc.
+Example (error handling omitted):
+
+    char user[20];
+    struct mg_str *hdr = mg_get_http_header(hm, "Authorization");
+    mg_http_parse_header(hdr, "username", user, sizeof(user));
+
+Returns the length of the variable's value. If buffer is not large enough,
+or variable not found, 0 is returned. 
+
@@ -0,0 +1,19 @@
+---
+title: "mg_http_reverse_proxy()"
+decl_name: "mg_http_reverse_proxy"
+symbol_kind: "func"
+signature: |
+  void mg_http_reverse_proxy(struct mg_connection *nc,
+                             const struct http_message *hm, struct mg_str mount,
+                             struct mg_str upstream);
+---
+
+Proxies a given request to a given upstream http server. The path prefix
+in `mount` will be stripped of the path requested to the upstream server,
+e.g. if mount is /api and upstream is http://localhost:8001/foo
+then an incoming request to /api/bar will cause a request to
+http://localhost:8001/foo/bar
+
+EXPERIMENTAL API. Please use http_serve_http + url_rewrites if a static
+mapping is good enough. 
+
@@ -0,0 +1,11 @@
+---
+title: "mg_http_send_error()"
+decl_name: "mg_http_send_error"
+symbol_kind: "func"
+signature: |
+  void mg_http_send_error(struct mg_connection *nc, int code, const char *reason);
+---
+
+Sends an error response. If reason is NULL, the message will be inferred
+from the error code (if supported). 
+
@@ -0,0 +1,20 @@
+---
+title: "mg_http_send_redirect()"
+decl_name: "mg_http_send_redirect"
+symbol_kind: "func"
+signature: |
+  void mg_http_send_redirect(struct mg_connection *nc, int status_code,
+                             const struct mg_str location,
+                             const struct mg_str extra_headers);
+---
+
+Sends a redirect response.
+`status_code` should be either 301 or 302 and `location` point to the
+new location.
+If `extra_headers` is not empty, then `extra_headers` are also sent
+after the response line. `extra_headers` must NOT end end with new line.
+
+Example:
+
+     mg_http_send_redirect(nc, 302, mg_mk_str("/login"), mg_mk_str(NULL)); 
+
@@ -0,0 +1,28 @@
+---
+title: "mg_http_serve_file()"
+decl_name: "mg_http_serve_file"
+symbol_kind: "func"
+signature: |
+  void mg_http_serve_file(struct mg_connection *nc, struct http_message *hm,
+                          const char *path, const struct mg_str mime_type,
+                          const struct mg_str extra_headers);
+---
+
+Serves a specific file with a given MIME type and optional extra headers.
+
+Example code snippet:
+
+```c
+static void ev_handler(struct mg_connection *nc, int ev, void *ev_data) {
+  switch (ev) {
+    case MG_EV_HTTP_REQUEST: {
+      struct http_message *hm = (struct http_message *) ev_data;
+      mg_http_serve_file(nc, hm, "file.txt",
+                         mg_mk_str("text/plain"), mg_mk_str(""));
+      break;
+    }
+    ...
+  }
+}
+``` 
+
@@ -0,0 +1,15 @@
+---
+title: "mg_parse_http()"
+decl_name: "mg_parse_http"
+symbol_kind: "func"
+signature: |
+  int mg_parse_http(const char *s, int n, struct http_message *hm, int is_req);
+---
+
+Parses a HTTP message.
+
+`is_req` should be set to 1 if parsing a request, 0 if reply.
+
+Returns the number of bytes parsed. If HTTP message is
+incomplete `0` is returned. On parse error, a negative number is returned. 
+
@@ -0,0 +1,13 @@
+---
+title: "mg_parse_http_basic_auth()"
+decl_name: "mg_parse_http_basic_auth"
+symbol_kind: "func"
+signature: |
+  int mg_parse_http_basic_auth(struct mg_str *hdr, char *user, size_t user_len,
+                               char *pass, size_t pass_len);
+---
+
+Parses the Authorization: Basic header
+Returns -1 iif the authorization type is not "Basic" or any other error such
+as incorrectly encoded base64 user password pair. 
+
@@ -0,0 +1,46 @@
+---
+title: "mg_parse_multipart()"
+decl_name: "mg_parse_multipart"
+symbol_kind: "func"
+signature: |
+  size_t mg_parse_multipart(const char *buf, size_t buf_len, char *var_name,
+                            size_t var_name_len, char *file_name,
+                            size_t file_name_len, const char **chunk,
+                            size_t *chunk_len);
+---
+
+Parses the buffer `buf`, `buf_len` that contains multipart form data chunks.
+Stores the chunk name in a `var_name`, `var_name_len` buffer.
+If a chunk is an uploaded file, then `file_name`, `file_name_len` is
+filled with an uploaded file name. `chunk`, `chunk_len`
+points to the chunk data.
+
+Return: number of bytes to skip to the next chunk or 0 if there are
+        no more chunks.
+
+Usage example:
+
+```c
+   static void ev_handler(struct mg_connection *nc, int ev, void *ev_data) {
+     switch(ev) {
+       case MG_EV_HTTP_REQUEST: {
+         struct http_message *hm = (struct http_message *) ev_data;
+         char var_name[100], file_name[100];
+         const char *chunk;
+         size_t chunk_len, n1, n2;
+
+         n1 = n2 = 0;
+         while ((n2 = mg_parse_multipart(hm->body.p + n1,
+                                         hm->body.len - n1,
+                                         var_name, sizeof(var_name),
+                                         file_name, sizeof(file_name),
+                                         &chunk, &chunk_len)) > 0) {
+           printf("var: %s, file_name: %s, size: %d, chunk: [%.*s]\n",
+                  var_name, file_name, (int) chunk_len,
+                  (int) chunk_len, chunk);
+           n1 += n2;
+         }
+       }
+       break;
+``` 
+
@@ -0,0 +1,10 @@
+---
+title: "mg_printf_html_escape()"
+decl_name: "mg_printf_html_escape"
+symbol_kind: "func"
+signature: |
+  void mg_printf_html_escape(struct mg_connection *nc, const char *fmt, ...);
+---
+
+Sends a printf-formatted HTTP chunk, escaping HTML tags. 
+
@@ -0,0 +1,11 @@
+---
+title: "mg_printf_http_chunk()"
+decl_name: "mg_printf_http_chunk"
+symbol_kind: "func"
+signature: |
+  void mg_printf_http_chunk(struct mg_connection *nc, const char *fmt, ...);
+---
+
+Sends a printf-formatted HTTP chunk.
+Functionality is similar to `mg_send_http_chunk()`. 
+
@@ -0,0 +1,36 @@
+---
+title: "mg_register_http_endpoint()"
+decl_name: "mg_register_http_endpoint"
+symbol_kind: "func"
+signature: |
+  void mg_register_http_endpoint(struct mg_connection *nc, const char *uri_path,
+                                 MG_CB(mg_event_handler_t handler,
+                                       void *user_data);
+---
+
+Registers a callback for a specified http endpoint
+Note: if callback is registered it is called instead of the
+callback provided in mg_bind
+
+Example code snippet:
+
+```c
+static void handle_hello1(struct mg_connection *nc, int ev, void *ev_data) {
+  (void) ev; (void) ev_data;
+  mg_printf(nc, "HTTP/1.0 200 OK\r\n\r\n[I am Hello1]");
+ nc->flags |= MG_F_SEND_AND_CLOSE;
+}
+
+static void handle_hello2(struct mg_connection *nc, int ev, void *ev_data) {
+ (void) ev; (void) ev_data;
+  mg_printf(nc, "HTTP/1.0 200 OK\r\n\r\n[I am Hello2]");
+ nc->flags |= MG_F_SEND_AND_CLOSE;
+}
+
+void init() {
+  nc = mg_bind(&mgr, local_addr, cb1);
+  mg_register_http_endpoint(nc, "/hello1", handle_hello1);
+  mg_register_http_endpoint(nc, "/hello1/hello2", handle_hello2);
+}
+``` 
+
@@ -0,0 +1,22 @@
+---
+title: "mg_send_head()"
+decl_name: "mg_send_head"
+symbol_kind: "func"
+signature: |
+  void mg_send_head(struct mg_connection *n, int status_code,
+                    int64_t content_length, const char *extra_headers);
+---
+
+Sends the response line and headers.
+This function sends the response line with the `status_code`, and
+automatically
+sends one header: either "Content-Length" or "Transfer-Encoding".
+If `content_length` is negative, then "Transfer-Encoding: chunked" header
+is sent, otherwise, "Content-Length" header is sent.
+
+NOTE: If `Transfer-Encoding` is `chunked`, then message body must be sent
+using `mg_send_http_chunk()` or `mg_printf_http_chunk()` functions.
+Otherwise, `mg_send()` or `mg_printf()` must be used.
+Extra headers could be set through `extra_headers`. Note `extra_headers`
+must NOT be terminated by a new line. 
+
@@ -0,0 +1,25 @@
+---
+title: "mg_send_http_chunk()"
+decl_name: "mg_send_http_chunk"
+symbol_kind: "func"
+signature: |
+  void mg_send_http_chunk(struct mg_connection *nc, const char *buf, size_t len);
+---
+
+Sends buffer `buf` of size `len` to the client using chunked HTTP encoding.
+This function sends the buffer size as hex number + newline first, then
+the buffer itself, then the newline. For example,
+`mg_send_http_chunk(nc, "foo", 3)` will append the `3\r\nfoo\r\n` string
+to the `nc->send_mbuf` output IO buffer.
+
+NOTE: The HTTP header "Transfer-Encoding: chunked" should be sent prior to
+using this function.
+
+NOTE: do not forget to send an empty chunk at the end of the response,
+to tell the client that everything was sent. Example:
+
+```
+  mg_printf_http_chunk(nc, "%s", "my response!");
+  mg_send_http_chunk(nc, "", 0); // Tell the client we're finished
+``` 
+
@@ -0,0 +1,21 @@
+---
+title: "mg_send_response_line()"
+decl_name: "mg_send_response_line"
+symbol_kind: "func"
+signature: |
+  void mg_send_response_line(struct mg_connection *nc, int status_code,
+                             const char *extra_headers);
+---
+
+Sends the response status line.
+If `extra_headers` is not NULL, then `extra_headers` are also sent
+after the response line. `extra_headers` must NOT end end with new line.
+Example:
+
+     mg_send_response_line(nc, 200, "Access-Control-Allow-Origin: *");
+
+Will result in:
+
+     HTTP/1.1 200 OK\r\n
+     Access-Control-Allow-Origin: *\r\n 
+
@@ -0,0 +1,28 @@
+---
+title: "mg_serve_http()"
+decl_name: "mg_serve_http"
+symbol_kind: "func"
+signature: |
+  void mg_serve_http(struct mg_connection *nc, struct http_message *hm,
+                     struct mg_serve_http_opts opts);
+---
+
+Serves given HTTP request according to the `options`.
+
+Example code snippet:
+
+```c
+static void ev_handler(struct mg_connection *nc, int ev, void *ev_data) {
+  struct http_message *hm = (struct http_message *) ev_data;
+  struct mg_serve_http_opts opts = { .document_root = "/var/www" };  // C99
+
+  switch (ev) {
+    case MG_EV_HTTP_REQUEST:
+      mg_serve_http(nc, hm, opts);
+      break;
+    default:
+      break;
+  }
+}
+``` 
+
@@ -0,0 +1,165 @@
+---
+title: "struct mg_serve_http_opts"
+decl_name: "struct mg_serve_http_opts"
+symbol_kind: "struct"
+signature: |
+  struct mg_serve_http_opts {
+    /* Path to web root directory */
+    const char *document_root;
+  
+    /* List of index files. Default is "" */
+    const char *index_files;
+  
+    /*
+     * Leave as NULL to disable authentication.
+     * To enable directory protection with authentication, set this to ".htpasswd"
+     * Then, creating ".htpasswd" file in any directory automatically protects
+     * it with digest authentication.
+     * Use `mongoose` web server binary, or `htdigest` Apache utility to
+     * create/manipulate passwords file.
+     * Make sure `auth_domain` is set to a valid domain name.
+     */
+    const char *per_directory_auth_file;
+  
+    /* Authorization domain (domain name of this web server) */
+    const char *auth_domain;
+  
+    /*
+     * Leave as NULL to disable authentication.
+     * Normally, only selected directories in the document root are protected.
+     * If absolutely every access to the web server needs to be authenticated,
+     * regardless of the URI, set this option to the path to the passwords file.
+     * Format of that file is the same as ".htpasswd" file. Make sure that file
+     * is located outside document root to prevent people fetching it.
+     */
+    const char *global_auth_file;
+  
+    /* Set to "no" to disable directory listing. Enabled by default. */
+    const char *enable_directory_listing;
+  
+    /*
+     * SSI files pattern. If not set, "**.shtml$|**.shtm$" is used.
+     *
+     * All files that match ssi_pattern are treated as SSI.
+     *
+     * Server Side Includes (SSI) is a simple interpreted server-side scripting
+     * language which is most commonly used to include the contents of a file
+     * into a web page. It can be useful when it is desirable to include a common
+     * piece of code throughout a website, for example, headers and footers.
+     *
+     * In order for a webpage to recognize an SSI-enabled HTML file, the
+     * filename should end with a special extension, by default the extension
+     * should be either .shtml or .shtm
+     *
+     * Unknown SSI directives are silently ignored by Mongoose. Currently,
+     * the following SSI directives are supported:
+     *    &lt;!--#include FILE_TO_INCLUDE --&gt;
+     *    &lt;!--#exec "COMMAND_TO_EXECUTE" --&gt;
+     *    &lt;!--#call COMMAND --&gt;
+     *
+     * Note that &lt;!--#include ...> directive supports three path
+     *specifications:
+     *
+     * &lt;!--#include virtual="path" --&gt;  Path is relative to web server root
+     * &lt;!--#include abspath="path" --&gt;  Path is absolute or relative to the
+     *                                  web server working dir
+     * &lt;!--#include file="path" --&gt;,    Path is relative to current document
+     * &lt;!--#include "path" --&gt;
+     *
+     * The include directive may be used to include the contents of a file or
+     * the result of running a CGI script.
+     *
+     * The exec directive is used to execute
+     * a command on a server, and show command's output. Example:
+     *
+     * &lt;!--#exec "ls -l" --&gt;
+     *
+     * The call directive is a way to invoke a C handler from the HTML page.
+     * On each occurence of &lt;!--#call COMMAND OPTIONAL_PARAMS> directive,
+     * Mongoose calls a registered event handler with MG_EV_SSI_CALL event,
+     * and event parameter will point to the COMMAND OPTIONAL_PARAMS string.
+     * An event handler can output any text, for example by calling
+     * `mg_printf()`. This is a flexible way of generating a web page on
+     * server side by calling a C event handler. Example:
+     *
+     * &lt;!--#call foo --&gt; ... &lt;!--#call bar --&gt;
+     *
+     * In the event handler:
+     *    case MG_EV_SSI_CALL: {
+     *      const char *param = (const char *) ev_data;
+     *      if (strcmp(param, "foo") == 0) {
+     *        mg_printf(c, "hello from foo");
+     *      } else if (strcmp(param, "bar") == 0) {
+     *        mg_printf(c, "hello from bar");
+     *      }
+     *      break;
+     *    }
+     */
+    const char *ssi_pattern;
+  
+    /* IP ACL. By default, NULL, meaning all IPs are allowed to connect */
+    const char *ip_acl;
+  
+  #if MG_ENABLE_HTTP_URL_REWRITES
+    /* URL rewrites.
+     *
+     * Comma-separated list of `uri_pattern=url_file_or_directory_path` rewrites.
+     * When HTTP request is received, Mongoose constructs a file name from the
+     * requested URI by combining `document_root` and the URI. However, if the
+     * rewrite option is used and `uri_pattern` matches requested URI, then
+     * `document_root` is ignored. Instead, `url_file_or_directory_path` is used,
+     * which should be a full path name or a path relative to the web server's
+     * current working directory. It can also be an URI (http:// or https://)
+     * in which case mongoose will behave as a reverse proxy for that destination.
+     *
+     * Note that `uri_pattern`, as all Mongoose patterns, is a prefix pattern.
+     *
+     * If uri_pattern starts with `@` symbol, then Mongoose compares it with the
+     * HOST header of the request. If they are equal, Mongoose sets document root
+     * to `file_or_directory_path`, implementing virtual hosts support.
+     * Example: `@foo.com=/document/root/for/foo.com`
+     *
+     * If `uri_pattern` starts with `%` symbol, then Mongoose compares it with
+     * the listening port. If they match, then Mongoose issues a 301 redirect.
+     * For example, to redirect all HTTP requests to the
+     * HTTPS port, do `%80=https://my.site.com`. Note that the request URI is
+     * automatically appended to the redirect location.
+     */
+    const char *url_rewrites;
+  #endif
+  
+    /* DAV document root. If NULL, DAV requests are going to fail. */
+    const char *dav_document_root;
+  
+    /*
+     * DAV passwords file. If NULL, DAV requests are going to fail.
+     * If passwords file is set to "-", then DAV auth is disabled.
+     */
+    const char *dav_auth_file;
+  
+    /* Glob pattern for the files to hide. */
+    const char *hidden_file_pattern;
+  
+    /* Set to non-NULL to enable CGI, e.g. **.cgi$|**.php$" */
+    const char *cgi_file_pattern;
+  
+    /* If not NULL, ignore CGI script hashbang and use this interpreter */
+    const char *cgi_interpreter;
+  
+    /*
+     * Comma-separated list of Content-Type overrides for path suffixes, e.g.
+     * ".txt=text/plain; charset=utf-8,.c=text/plain"
+     */
+    const char *custom_mime_types;
+  
+    /*
+     * Extra HTTP headers to add to each server response.
+     * Example: to enable CORS, set this to "Access-Control-Allow-Origin: *".
+     */
+    const char *extra_headers;
+  };
+---
+
+This structure defines how `mg_serve_http()` works.
+Best practice is to set only required settings, and leave the rest as NULL. 
+
@@ -0,0 +1,16 @@
+---
+items:
+  - { name: mbuf.h }
+  - { name: net.h }
+  - { name: http.h }
+  - { name: http_server.h }
+  - { name: http_client.h }
+  - { name: dns.h }
+  - { name: dns_server.h }
+  - { name: resolv.h }
+  - { name: mqtt.h }
+  - { name: mqtt_server.h }
+  - { name: coap.h }
+  - { name: util.h }
+  - { name: uri.h }
+---
@@ -0,0 +1,20 @@
+---
+title: "Memory Buffers"
+symbol_kind: "intro"
+decl_name: "mbuf.h"
+items:
+  - { name: mbuf_append.md }
+  - { name: mbuf_free.md }
+  - { name: mbuf_init.md }
+  - { name: mbuf_insert.md }
+  - { name: mbuf_remove.md }
+  - { name: mbuf_resize.md }
+  - { name: mbuf_trim.md }
+  - { name: struct_mbuf.md }
+---
+
+Mbufs are mutable/growing memory buffers, like C++ strings.
+Mbuf can append data to the end of a buffer or insert data into arbitrary
+position in the middle of a buffer. The buffer grows automatically when
+needed.
+
@@ -0,0 +1,12 @@
+---
+title: "mbuf_append()"
+decl_name: "mbuf_append"
+symbol_kind: "func"
+signature: |
+  size_t mbuf_append(struct mbuf *, const void *data, size_t data_size);
+---
+
+Appends data to the Mbuf.
+
+Returns the number of bytes appended or 0 if out of memory. 
+
@@ -0,0 +1,10 @@
+---
+title: "mbuf_free()"
+decl_name: "mbuf_free"
+symbol_kind: "func"
+signature: |
+  void mbuf_free(struct mbuf *);
+---
+
+Frees the space allocated for the mbuffer and resets the mbuf structure. 
+
@@ -0,0 +1,11 @@
+---
+title: "mbuf_init()"
+decl_name: "mbuf_init"
+symbol_kind: "func"
+signature: |
+  void mbuf_init(struct mbuf *, size_t initial_capacity);
+---
+
+Initialises an Mbuf.
+`initial_capacity` specifies the initial capacity of the mbuf. 
+
@@ -0,0 +1,14 @@
+---
+title: "mbuf_insert()"
+decl_name: "mbuf_insert"
+symbol_kind: "func"
+signature: |
+  size_t mbuf_insert(struct mbuf *, size_t, const void *, size_t);
+---
+
+Inserts data at a specified offset in the Mbuf.
+
+Existing data will be shifted forwards and the buffer will
+be grown if necessary.
+Returns the number of bytes inserted. 
+
@@ -0,0 +1,10 @@
+---
+title: "mbuf_remove()"
+decl_name: "mbuf_remove"
+symbol_kind: "func"
+signature: |
+  void mbuf_remove(struct mbuf *, size_t data_size);
+---
+
+Removes `data_size` bytes from the beginning of the buffer. 
+
@@ -0,0 +1,13 @@
+---
+title: "mbuf_resize()"
+decl_name: "mbuf_resize"
+symbol_kind: "func"
+signature: |
+  void mbuf_resize(struct mbuf *, size_t new_size);
+---
+
+Resizes an Mbuf.
+
+If `new_size` is smaller than buffer's `len`, the
+resize is not performed. 
+
@@ -0,0 +1,10 @@
+---
+title: "mbuf_trim()"
+decl_name: "mbuf_trim"
+symbol_kind: "func"
+signature: |
+  void mbuf_trim(struct mbuf *);
+---
+
+Shrinks an Mbuf by resizing its `size` to `len`. 
+
@@ -0,0 +1,14 @@
+---
+title: "struct mbuf"
+decl_name: "struct mbuf"
+symbol_kind: "struct"
+signature: |
+  struct mbuf {
+    char *buf;   /* Buffer pointer */
+    size_t len;  /* Data length. Data is located between offset 0 and len. */
+    size_t size; /* Buffer size allocated by realloc(1). Must be >= len */
+  };
+---
+
+Memory buffer descriptor 
+
@@ -0,0 +1,29 @@
+---
+title: "MQTT API reference"
+symbol_kind: "intro"
+decl_name: "mqtt.h"
+items:
+  - { name: mg_mqtt_connack.md }
+  - { name: mg_mqtt_disconnect.md }
+  - { name: mg_mqtt_match_topic_expression.md }
+  - { name: mg_mqtt_next_subscribe_topic.md }
+  - { name: mg_mqtt_ping.md }
+  - { name: mg_mqtt_pong.md }
+  - { name: mg_mqtt_puback.md }
+  - { name: mg_mqtt_pubcomp.md }
+  - { name: mg_mqtt_publish.md }
+  - { name: mg_mqtt_pubrec.md }
+  - { name: mg_mqtt_pubrel.md }
+  - { name: mg_mqtt_suback.md }
+  - { name: mg_mqtt_subscribe.md }
+  - { name: mg_mqtt_unsuback.md }
+  - { name: mg_mqtt_unsubscribe.md }
+  - { name: mg_mqtt_vmatch_topic_expression.md }
+  - { name: mg_send_mqtt_handshake.md }
+  - { name: mg_send_mqtt_handshake_opt.md }
+  - { name: mg_set_protocol_mqtt.md }
+  - { name: struct_mg_mqtt_proto_data.md }
+---
+
+
+
@@ -0,0 +1,10 @@
+---
+title: "mg_mqtt_connack()"
+decl_name: "mg_mqtt_connack"
+symbol_kind: "func"
+signature: |
+  void mg_mqtt_connack(struct mg_connection *nc, uint8_t return_code);
+---
+
+Sends a CONNACK command with a given `return_code`. 
+
@@ -0,0 +1,10 @@
+---
+title: "mg_mqtt_disconnect()"
+decl_name: "mg_mqtt_disconnect"
+symbol_kind: "func"
+signature: |
+  void mg_mqtt_disconnect(struct mg_connection *nc);
+---
+
+Sends a DISCONNECT command. 
+
@@ -0,0 +1,12 @@
+---
+title: "mg_mqtt_match_topic_expression()"
+decl_name: "mg_mqtt_match_topic_expression"
+symbol_kind: "func"
+signature: |
+  int mg_mqtt_match_topic_expression(struct mg_str exp, struct mg_str topic);
+---
+
+Matches a topic against a topic expression
+
+Returns 1 if it matches; 0 otherwise. 
+
@@ -0,0 +1,15 @@
+---
+title: "mg_mqtt_next_subscribe_topic()"
+decl_name: "mg_mqtt_next_subscribe_topic"
+symbol_kind: "func"
+signature: |
+  int mg_mqtt_next_subscribe_topic(struct mg_mqtt_message *msg,
+                                   struct mg_str *topic, uint8_t *qos, int pos);
+---
+
+Extracts the next topic expression from a SUBSCRIBE command payload.
+
+The topic expression name will point to a string in the payload buffer.
+Returns the pos of the next topic expression or -1 when the list
+of topics is exhausted. 
+
@@ -0,0 +1,10 @@
+---
+title: "mg_mqtt_ping()"
+decl_name: "mg_mqtt_ping"
+symbol_kind: "func"
+signature: |
+  void mg_mqtt_ping(struct mg_connection *nc);
+---
+
+Sends a PINGREQ command. 
+
@@ -0,0 +1,10 @@
+---
+title: "mg_mqtt_pong()"
+decl_name: "mg_mqtt_pong"
+symbol_kind: "func"
+signature: |
+  void mg_mqtt_pong(struct mg_connection *nc);
+---
+
+Sends a PINGRESP command. 
+
@@ -0,0 +1,10 @@
+---
+title: "mg_mqtt_puback()"
+decl_name: "mg_mqtt_puback"
+symbol_kind: "func"
+signature: |
+  void mg_mqtt_puback(struct mg_connection *nc, uint16_t message_id);
+---
+
+Sends a PUBACK command with a given `message_id`. 
+
@@ -0,0 +1,10 @@
+---
+title: "mg_mqtt_pubcomp()"
+decl_name: "mg_mqtt_pubcomp"
+symbol_kind: "func"
+signature: |
+  void mg_mqtt_pubcomp(struct mg_connection *nc, uint16_t message_id);
+---
+
+Sends a PUBCOMP command with a given `message_id`. 
+
@@ -0,0 +1,12 @@
+---
+title: "mg_mqtt_publish()"
+decl_name: "mg_mqtt_publish"
+symbol_kind: "func"
+signature: |
+  void mg_mqtt_publish(struct mg_connection *nc, const char *topic,
+                       uint16_t message_id, int flags, const void *data,
+                       size_t len);
+---
+
+Publishes a message to a given topic. 
+
@@ -0,0 +1,10 @@
+---
+title: "mg_mqtt_pubrec()"
+decl_name: "mg_mqtt_pubrec"
+symbol_kind: "func"
+signature: |
+  void mg_mqtt_pubrec(struct mg_connection *nc, uint16_t message_id);
+---
+
+Sends a PUBREC command with a given `message_id`. 
+
@@ -0,0 +1,10 @@
+---
+title: "mg_mqtt_pubrel()"
+decl_name: "mg_mqtt_pubrel"
+symbol_kind: "func"
+signature: |
+  void mg_mqtt_pubrel(struct mg_connection *nc, uint16_t message_id);
+---
+
+Sends a PUBREL command with a given `message_id`. 
+
@@ -0,0 +1,12 @@
+---
+title: "mg_mqtt_suback()"
+decl_name: "mg_mqtt_suback"
+symbol_kind: "func"
+signature: |
+  void mg_mqtt_suback(struct mg_connection *nc, uint8_t *qoss, size_t qoss_len,
+                      uint16_t message_id);
+---
+
+Sends a SUBACK command with a given `message_id`
+and a sequence of granted QoSs. 
+
@@ -0,0 +1,12 @@
+---
+title: "mg_mqtt_subscribe()"
+decl_name: "mg_mqtt_subscribe"
+symbol_kind: "func"
+signature: |
+  void mg_mqtt_subscribe(struct mg_connection *nc,
+                         const struct mg_mqtt_topic_expression *topics,
+                         size_t topics_len, uint16_t message_id);
+---
+
+Subscribes to a bunch of topics. 
+
@@ -0,0 +1,10 @@
+---
+title: "mg_mqtt_unsuback()"
+decl_name: "mg_mqtt_unsuback"
+symbol_kind: "func"
+signature: |
+  void mg_mqtt_unsuback(struct mg_connection *nc, uint16_t message_id);
+---
+
+Sends a UNSUBACK command with a given `message_id`. 
+
@@ -0,0 +1,11 @@
+---
+title: "mg_mqtt_unsubscribe()"
+decl_name: "mg_mqtt_unsubscribe"
+symbol_kind: "func"
+signature: |
+  void mg_mqtt_unsubscribe(struct mg_connection *nc, char **topics,
+                           size_t topics_len, uint16_t message_id);
+---
+
+Unsubscribes from a bunch of topics. 
+