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#ifndef INCLUDE_LLHTTP_API_H_
#define INCLUDE_LLHTTP_API_H_
#ifdef __cplusplus
extern "C" {
#endif
#include <stddef.h>
#if defined(__wasm__)
#define LLHTTP_EXPORT __attribute__((visibility("default")))
#else
#define LLHTTP_EXPORT
#endif
typedef llhttp__internal_t llhttp_t;
typedef struct llhttp_settings_s llhttp_settings_t;
typedef int (*llhttp_data_cb)(llhttp_t*, const char *at, size_t length);
typedef int (*llhttp_cb)(llhttp_t*);
struct llhttp_settings_s {
/* Possible return values 0, -1, `HPE_PAUSED` */
llhttp_cb on_message_begin;
/* Possible return values 0, -1, HPE_USER */
llhttp_data_cb on_url;
llhttp_data_cb on_status;
llhttp_data_cb on_method;
llhttp_data_cb on_version;
llhttp_data_cb on_header_field;
llhttp_data_cb on_header_value;
llhttp_data_cb on_chunk_extension_name;
llhttp_data_cb on_chunk_extension_value;
/* Possible return values:
* 0 - Proceed normally
* 1 - Assume that request/response has no body, and proceed to parsing the
* next message
* 2 - Assume absence of body (as above) and make `llhttp_execute()` return
* `HPE_PAUSED_UPGRADE`
* -1 - Error
* `HPE_PAUSED`
*/
llhttp_cb on_headers_complete;
/* Possible return values 0, -1, HPE_USER */
llhttp_data_cb on_body;
/* Possible return values 0, -1, `HPE_PAUSED` */
llhttp_cb on_message_complete;
llhttp_cb on_url_complete;
llhttp_cb on_status_complete;
llhttp_cb on_method_complete;
llhttp_cb on_version_complete;
llhttp_cb on_header_field_complete;
llhttp_cb on_header_value_complete;
llhttp_cb on_chunk_extension_name_complete;
llhttp_cb on_chunk_extension_value_complete;
/* When on_chunk_header is called, the current chunk length is stored
* in parser->content_length.
* Possible return values 0, -1, `HPE_PAUSED`
*/
llhttp_cb on_chunk_header;
llhttp_cb on_chunk_complete;
llhttp_cb on_reset;
};
/* Initialize the parser with specific type and user settings.
*
* NOTE: lifetime of `settings` has to be at least the same as the lifetime of
* the `parser` here. In practice, `settings` has to be either a static
* variable or be allocated with `malloc`, `new`, etc.
*/
LLHTTP_EXPORT
void llhttp_init(llhttp_t* parser, llhttp_type_t type,
const llhttp_settings_t* settings);
LLHTTP_EXPORT
llhttp_t* llhttp_alloc(llhttp_type_t type);
LLHTTP_EXPORT
void llhttp_free(llhttp_t* parser);
LLHTTP_EXPORT
uint8_t llhttp_get_type(llhttp_t* parser);
LLHTTP_EXPORT
uint8_t llhttp_get_http_major(llhttp_t* parser);
LLHTTP_EXPORT
uint8_t llhttp_get_http_minor(llhttp_t* parser);
LLHTTP_EXPORT
uint8_t llhttp_get_method(llhttp_t* parser);
LLHTTP_EXPORT
int llhttp_get_status_code(llhttp_t* parser);
LLHTTP_EXPORT
uint8_t llhttp_get_upgrade(llhttp_t* parser);
/* Reset an already initialized parser back to the start state, preserving the
* existing parser type, callback settings, user data, and lenient flags.
*/
LLHTTP_EXPORT
void llhttp_reset(llhttp_t* parser);
/* Initialize the settings object */
LLHTTP_EXPORT
void llhttp_settings_init(llhttp_settings_t* settings);
/* Parse full or partial request/response, invoking user callbacks along the
* way.
*
* If any of `llhttp_data_cb` returns errno not equal to `HPE_OK` - the parsing
* interrupts, and such errno is returned from `llhttp_execute()`. If
* `HPE_PAUSED` was used as a errno, the execution can be resumed with
* `llhttp_resume()` call.
*
* In a special case of CONNECT/Upgrade request/response `HPE_PAUSED_UPGRADE`
* is returned after fully parsing the request/response. If the user wishes to
* continue parsing, they need to invoke `llhttp_resume_after_upgrade()`.
*
* NOTE: if this function ever returns a non-pause type error, it will continue
* to return the same error upon each successive call up until `llhttp_init()`
* is called.
*/
LLHTTP_EXPORT
llhttp_errno_t llhttp_execute(llhttp_t* parser, const char* data, size_t len);
/* This method should be called when the other side has no further bytes to
* send (e.g. shutdown of readable side of the TCP connection.)
*
* Requests without `Content-Length` and other messages might require treating
* all incoming bytes as the part of the body, up to the last byte of the
* connection. This method will invoke `on_message_complete()` callback if the
* request was terminated safely. Otherwise a error code would be returned.
*/
LLHTTP_EXPORT
llhttp_errno_t llhttp_finish(llhttp_t* parser);
/* Returns `1` if the incoming message is parsed until the last byte, and has
* to be completed by calling `llhttp_finish()` on EOF
*/
LLHTTP_EXPORT
int llhttp_message_needs_eof(const llhttp_t* parser);
/* Returns `1` if there might be any other messages following the last that was
* successfully parsed.
*/
LLHTTP_EXPORT
int llhttp_should_keep_alive(const llhttp_t* parser);
/* Make further calls of `llhttp_execute()` return `HPE_PAUSED` and set
* appropriate error reason.
*
* Important: do not call this from user callbacks! User callbacks must return
* `HPE_PAUSED` if pausing is required.
*/
LLHTTP_EXPORT
void llhttp_pause(llhttp_t* parser);
/* Might be called to resume the execution after the pause in user's callback.
* See `llhttp_execute()` above for details.
*
* Call this only if `llhttp_execute()` returns `HPE_PAUSED`.
*/
LLHTTP_EXPORT
void llhttp_resume(llhttp_t* parser);
/* Might be called to resume the execution after the pause in user's callback.
* See `llhttp_execute()` above for details.
*
* Call this only if `llhttp_execute()` returns `HPE_PAUSED_UPGRADE`
*/
LLHTTP_EXPORT
void llhttp_resume_after_upgrade(llhttp_t* parser);
/* Returns the latest return error */
LLHTTP_EXPORT
llhttp_errno_t llhttp_get_errno(const llhttp_t* parser);
/* Returns the verbal explanation of the latest returned error.
*
* Note: User callback should set error reason when returning the error. See
* `llhttp_set_error_reason()` for details.
*/
LLHTTP_EXPORT
const char* llhttp_get_error_reason(const llhttp_t* parser);
/* Assign verbal description to the returned error. Must be called in user
* callbacks right before returning the errno.
*
* Note: `HPE_USER` error code might be useful in user callbacks.
*/
LLHTTP_EXPORT
void llhttp_set_error_reason(llhttp_t* parser, const char* reason);
/* Returns the pointer to the last parsed byte before the returned error. The
* pointer is relative to the `data` argument of `llhttp_execute()`.
*
* Note: this method might be useful for counting the number of parsed bytes.
*/
LLHTTP_EXPORT
const char* llhttp_get_error_pos(const llhttp_t* parser);
/* Returns textual name of error code */
LLHTTP_EXPORT
const char* llhttp_errno_name(llhttp_errno_t err);
/* Returns textual name of HTTP method */
LLHTTP_EXPORT
const char* llhttp_method_name(llhttp_method_t method);
/* Returns textual name of HTTP status */
LLHTTP_EXPORT
const char* llhttp_status_name(llhttp_status_t status);
/* Enables/disables lenient header value parsing (disabled by default).
*
* Lenient parsing disables header value token checks, extending llhttp's
* protocol support to highly non-compliant clients/server. No
* `HPE_INVALID_HEADER_TOKEN` will be raised for incorrect header values when
* lenient parsing is "on".
*
* **(USE AT YOUR OWN RISK)**
*/
LLHTTP_EXPORT
void llhttp_set_lenient_headers(llhttp_t* parser, int enabled);
/* Enables/disables lenient handling of conflicting `Transfer-Encoding` and
* `Content-Length` headers (disabled by default).
*
* Normally `llhttp` would error when `Transfer-Encoding` is present in
* conjunction with `Content-Length`. This error is important to prevent HTTP
* request smuggling, but may be less desirable for small number of cases
* involving legacy servers.
*
* **(USE AT YOUR OWN RISK)**
*/
LLHTTP_EXPORT
void llhttp_set_lenient_chunked_length(llhttp_t* parser, int enabled);
/* Enables/disables lenient handling of `Connection: close` and HTTP/1.0
* requests responses.
*
* Normally `llhttp` would error on (in strict mode) or discard (in loose mode)
* the HTTP request/response after the request/response with `Connection: close`
* and `Content-Length`. This is important to prevent cache poisoning attacks,
* but might interact badly with outdated and insecure clients. With this flag
* the extra request/response will be parsed normally.
*
* **(USE AT YOUR OWN RISK)**
*/
LLHTTP_EXPORT
void llhttp_set_lenient_keep_alive(llhttp_t* parser, int enabled);
/* Enables/disables lenient handling of `Transfer-Encoding` header.
*
* Normally `llhttp` would error when a `Transfer-Encoding` has `chunked` value
* and another value after it (either in a single header or in multiple
* headers whose value are internally joined using `, `).
* This is mandated by the spec to reliably determine request body size and thus
* avoid request smuggling.
* With this flag the extra value will be parsed normally.
*
* **(USE AT YOUR OWN RISK)**
*/
LLHTTP_EXPORT
void llhttp_set_lenient_transfer_encoding(llhttp_t* parser, int enabled);
#ifdef __cplusplus
} /* extern "C" */
#endif
#endif /* INCLUDE_LLHTTP_API_H_ */