mirror of
git://git.psyc.eu/libpsyc
synced 2024-08-15 03:19:02 +00:00
618 lines
17 KiB
C
618 lines
17 KiB
C
#ifndef PSYC_PARSE_H
|
|
#define PSYC_PARSE_H
|
|
|
|
/**
|
|
* @file psyc/parse.h
|
|
* @brief Interface for PSYC packet parsing.
|
|
*
|
|
* All parsing functions and the definitions they use are defined here.
|
|
*/
|
|
|
|
/**
|
|
* @defgroup parse Parsing Functions
|
|
*
|
|
* This module contains packet and list parsing functions.
|
|
* The parser adheres to the definition of a packet found at
|
|
*
|
|
* http://about.psyc.eu/Spec:Packet
|
|
*
|
|
* and the according terms are used throughout this documentation and in the
|
|
* return codes. You should be at least
|
|
* vaguely familiar with differences between "body" and "content" as
|
|
* well as "routing variable" and "entity variable".
|
|
*
|
|
*
|
|
* To parse a packet you first have to initialize a state:
|
|
*
|
|
* @code
|
|
* PsycParseState state;
|
|
* psyc_parse_state_init(&state, flags);
|
|
* @endcode
|
|
*
|
|
* With the flags parameter you can fine-tune what
|
|
* part of the packet should be parsed. @see PsycParseFlag
|
|
*
|
|
* Next, you have to tell the parser what it should parse. Assuming the variable
|
|
* raw_data points to our packet and raw_len contains the length, you can pass
|
|
* it to the parser as follows:
|
|
*
|
|
* @code
|
|
* char* raw_data; // points to our (possibly incomplete) packet
|
|
* size_t raw_len; // how many bytes of data
|
|
*
|
|
* // state is our initialized state from before
|
|
* psyc_parse_buffer_set(&state, raw_data, raw_len);
|
|
* @endcode
|
|
*
|
|
* Now the the variables that will save the output of the parser need to be
|
|
* declared:
|
|
*
|
|
* @code
|
|
* PsycString name, // Name of the variable or method
|
|
* value; // Value of the variable or body
|
|
* char oper; // operator of the variable (if any)
|
|
* @endcode
|
|
*
|
|
* They will be passed to the parsing function which will set them to
|
|
* the according positions and lengths.
|
|
*
|
|
* Now the real parsing begins. The parsing function needs to be called
|
|
* repeatedly with various actions in between, depending on the return values.
|
|
*
|
|
* A simplified example follows, see test/testPsyc.c for actual code that
|
|
* handles incomplete packets as well.
|
|
*
|
|
* @code
|
|
*
|
|
* int ret;
|
|
*
|
|
* do // run the parsing in a loop, each time parsing one line
|
|
* {
|
|
* name.length = value.length = oper = 0; // reset the output variables
|
|
*
|
|
* ret = psyc_parse(&state, &oper, &name, &value); // call the parsing function
|
|
*
|
|
* switch (ret) // look at the return value
|
|
* {
|
|
* case PSYC_PARSE_ROUTING: // it is a routing variable
|
|
* case PSYC_PARSE_ENTITY: // it is a entity variable
|
|
* // Name, value and operator of the variable can now be found in the
|
|
* // respective variables:
|
|
* printf("Variable: %.*s Value: %.*s Operator: %c\n",
|
|
* name.length, name.data,
|
|
* value.length, value.data,
|
|
* oper);
|
|
* // Note that the .data member still points at your original buffer. If
|
|
* // you want to reuse that buffer for the next packet, you better copy it
|
|
* // before passing it to the parser or you copy each variable now.
|
|
* break;
|
|
* case PSYC_PARSE_BODY: // it is the method and the body of the packet.
|
|
* printf("Method Name: %.*s Body: %.*s\n",
|
|
* name.length, name.data, // name of the method
|
|
* value.length, value.data); // value of the body
|
|
* break;
|
|
* case PSYC_PARSE_COMPLETE: // parsing of this packet is complete
|
|
* // You can simply continue parsing till you get the
|
|
* // PSYC_PARSE_INSUFFICIENT code which means the line is incomplete.
|
|
* continue;
|
|
* default: //
|
|
* perror("Error %i happened :(\n", res);
|
|
* return res;
|
|
* }
|
|
* }
|
|
* while (ret > 0)
|
|
* @endcode
|
|
*
|
|
* This simple example does not consider some more complex cases when you
|
|
* receive incomplete packets but still want to access the data. This code would
|
|
* simply reject incomplete packets as error. A more detailed tutorial for
|
|
* incomplete packets will follow. In the mean time, have look at the return
|
|
* codes in PsycParseRC and their explanations. @see PsycParseRC
|
|
*/
|
|
|
|
/** @{ */ // begin of parser group
|
|
|
|
#include <stdint.h>
|
|
#include <string.h>
|
|
#include <psyc.h>
|
|
|
|
typedef enum {
|
|
/// Default Flag. Parse everything.
|
|
PSYC_PARSE_ALL = 0,
|
|
/// Parse only the header
|
|
PSYC_PARSE_ROUTING_ONLY = 1,
|
|
/// Parse only the content.
|
|
/// Parsing starts at the content and the content must be complete.
|
|
PSYC_PARSE_START_AT_CONTENT = 2,
|
|
} PsycParseFlag;
|
|
|
|
/**
|
|
* The return value definitions for the packet parsing function.
|
|
* @see psyc_parse()
|
|
*/
|
|
typedef enum {
|
|
/// Error, packet is not ending with a valid delimiter.
|
|
PSYC_PARSE_ERROR_END = -8,
|
|
/// Error, expected NL after the method.
|
|
PSYC_PARSE_ERROR_METHOD = -7,
|
|
/// Error, expected NL after a modifier.
|
|
PSYC_PARSE_ERROR_MOD_NL = -6,
|
|
/// Error, modifier length is not numeric.
|
|
PSYC_PARSE_ERROR_MOD_LEN = -5,
|
|
/// Error, expected TAB before modifier value.
|
|
PSYC_PARSE_ERROR_MOD_TAB = -4,
|
|
/// Error, modifier name is missing.
|
|
PSYC_PARSE_ERROR_MOD_NAME = -3,
|
|
/// Error, expected NL after the content length.
|
|
PSYC_PARSE_ERROR_LENGTH = -2,
|
|
/// Error in packet.
|
|
PSYC_PARSE_ERROR = -1,
|
|
/// Buffer contains insufficient amount of data.
|
|
/// Fill another buffer and concatenate it with the end of the current buffer,
|
|
/// from the cursor position to the end.
|
|
PSYC_PARSE_INSUFFICIENT = 1,
|
|
/// Routing modifier parsing done.
|
|
/// Operator, name & value contains the respective parts.
|
|
PSYC_PARSE_ROUTING = 2,
|
|
/// State sync operation.
|
|
PSYC_PARSE_STATE_RESYNC = 3,
|
|
/// State reset operation.
|
|
PSYC_PARSE_STATE_RESET = 4,
|
|
/// Start of an incomplete entity modifier.
|
|
/// Operator & name are complete, value is incomplete.
|
|
PSYC_PARSE_ENTITY_START = 5,
|
|
/// Continuation of an incomplete entity modifier.
|
|
PSYC_PARSE_ENTITY_CONT = 6,
|
|
/// End of an incomplete entity modifier.
|
|
PSYC_PARSE_ENTITY_END = 7,
|
|
/// Entity modifier parsing done in one go.
|
|
/// Operator, name & value contains the respective parts.
|
|
PSYC_PARSE_ENTITY = 8,
|
|
/// Start of an incomplete body.
|
|
/// Name contains method, value contains part of the body.
|
|
/// Used when packet length is given
|
|
PSYC_PARSE_BODY_START = 9,
|
|
/// Continuation of an incomplete body.
|
|
/// Used when packet length is given
|
|
PSYC_PARSE_BODY_CONT = 10,
|
|
/// End of an incomplete body.
|
|
/// Used when packet length is given
|
|
PSYC_PARSE_BODY_END = 11,
|
|
/// Body parsing done in one go, name contains method, value contains body.
|
|
PSYC_PARSE_BODY = 12,
|
|
/// Start of an incomplete content, value contains part of content.
|
|
/// Used when PSYC_PARSE_ROUTING_ONLY is set.
|
|
PSYC_PARSE_CONTENT_START = 9,
|
|
/// Continuation of an incomplete content.
|
|
/// Used when PSYC_PARSE_ROUTING_ONLY is set.
|
|
PSYC_PARSE_CONTENT_CONT = 10,
|
|
/// End of an incomplete content.
|
|
/// Used when PSYC_PARSE_ROUTING_ONLY is set.
|
|
PSYC_PARSE_CONTENT_END = 11,
|
|
/// Content parsing done in one go, value contains the whole content.
|
|
/// Used when PSYC_PARSE_ROUTING_ONLY is set.
|
|
PSYC_PARSE_CONTENT = 12,
|
|
/// Finished parsing packet.
|
|
PSYC_PARSE_COMPLETE = 13,
|
|
} PsycParseRC;
|
|
|
|
/**
|
|
* The return value definitions for the list parsing function.
|
|
* @see psyc_parse_list()
|
|
*/
|
|
typedef enum {
|
|
PSYC_PARSE_LIST_ERROR_DELIM = -4,
|
|
PSYC_PARSE_LIST_ERROR_LEN = -3,
|
|
PSYC_PARSE_LIST_ERROR_TYPE = -2,
|
|
PSYC_PARSE_LIST_ERROR = -1,
|
|
/// Completed parsing a list element.
|
|
PSYC_PARSE_LIST_ELEM = 1,
|
|
/// Reached end of buffer.
|
|
PSYC_PARSE_LIST_END = 2,
|
|
/// Binary list is incomplete.
|
|
PSYC_PARSE_LIST_INCOMPLETE = 3,
|
|
} PsycParseListRC;
|
|
|
|
typedef enum {
|
|
PSYC_PARSE_TABLE_ERROR_BODY = -5,
|
|
PSYC_PARSE_TABLE_ERROR_DELIM = -4,
|
|
PSYC_PARSE_TABLE_ERROR_HEAD = -3,
|
|
PSYC_PARSE_TABLE_ERROR_WIDTH = -2,
|
|
PSYC_PARSE_TABLE_ERROR = -1,
|
|
/// Completed parsing the width of the table.
|
|
PSYC_PARSE_TABLE_WIDTH = 1,
|
|
#ifdef PSYC_PARSE_TABLE_HEAD
|
|
/// Completed parsing the name of the key column.
|
|
PSYC_PARSE_TABLE_NAME_KEY = 2,
|
|
/// Completed parsing the name of a value column.
|
|
PSYC_PARSE_TABLE_NAME_VALUE = 3,
|
|
#endif
|
|
/// Completed parsing a key.
|
|
PSYC_PARSE_TABLE_KEY = 4,
|
|
/// Completed parsing a value.
|
|
PSYC_PARSE_TABLE_VALUE = 5,
|
|
/// Completed parsing a key and reached end of buffer.
|
|
PSYC_PARSE_TABLE_KEY_END = 6,
|
|
/// Completed parsing a value and reached end of buffer.
|
|
PSYC_PARSE_TABLE_VALUE_END = 7,
|
|
/// Binary table is incomplete.
|
|
PSYC_PARSE_TABLE_INCOMPLETE = 8,
|
|
} PsycParseTableRC;
|
|
|
|
typedef enum {
|
|
PSYC_TABLE_PART_START = 0,
|
|
PSYC_TABLE_PART_WIDTH = 1,
|
|
#ifdef PSYC_PARSE_TABLE_HEAD
|
|
PSYC_TABLE_PART_HEAD_START = 2,
|
|
PSYC_TABLE_PART_HEAD = 3,
|
|
#endif
|
|
PSYC_TABLE_PART_BODY_START = 4,
|
|
PSYC_TABLE_PART_BODY = 5,
|
|
} PsycTablePart;
|
|
|
|
/**
|
|
* Struct for keeping parser state.
|
|
*/
|
|
typedef struct {
|
|
size_t cursor; ///< Current position in buffer.
|
|
size_t startc; ///< Position where the parsing would be resumed.
|
|
PsycString buffer; ///< Buffer with data to be parsed.
|
|
uint8_t flags; ///< Flags for the parser, see PsycParseFlag.
|
|
PsycPart part; ///< Part of the packet being parsed currently.
|
|
|
|
size_t routinglen; ///< Length of routing part parsed so far.
|
|
size_t content_parsed; ///< Number of bytes parsed from the content so far.
|
|
size_t contentlen; ///< Expected length of the content.
|
|
PsycBool contentlen_found; ///< Is there a length given for this packet?
|
|
size_t value_parsed; ///< Number of bytes parsed from the value so far.
|
|
size_t valuelen; ///< Expected length of the value.
|
|
PsycBool valuelen_found; ///< Is there a length given for this modifier?
|
|
} PsycParseState;
|
|
|
|
/**
|
|
* Struct for keeping list parser state.
|
|
*/
|
|
typedef struct {
|
|
size_t cursor; ///< Current position in buffer.
|
|
size_t startc; ///< Line start position.
|
|
PsycString buffer; ///< Buffer with data to be parsed.
|
|
PsycListType type; ///< List type.
|
|
char term; ///< Terminator character at the end.
|
|
uint8_t term_set; ///< Look for terminator.
|
|
|
|
size_t elem_parsed; ///< Number of bytes parsed from the elem so far.
|
|
size_t elemlen; ///< Expected length of the elem.
|
|
} PsycParseListState;
|
|
|
|
/**
|
|
* Struct for keeping table parser state.
|
|
*/
|
|
typedef struct {
|
|
size_t cursor; ///< Current position in buffer.
|
|
size_t startc; ///< Line start position.
|
|
PsycString buffer; ///< Buffer with data to be parsed.
|
|
PsycTablePart part; ///< Table type.
|
|
size_t width; ///< Width of table.
|
|
size_t elems; ///< Elems parsed so far in the table.
|
|
PsycParseListState list;
|
|
} PsycParseTableState;
|
|
|
|
/**
|
|
* Initializes the state struct.
|
|
*
|
|
* @param state Pointer to the state struct that should be initialized.
|
|
* @param flags Flags to be set for the parser, see PsycParseFlag.
|
|
* @see PsycParseFlag
|
|
*/
|
|
static inline void
|
|
psyc_parse_state_init (PsycParseState *state, uint8_t flags)
|
|
{
|
|
memset(state, 0, sizeof(PsycParseState));
|
|
state->flags = flags;
|
|
|
|
if (flags & PSYC_PARSE_START_AT_CONTENT)
|
|
state->part = PSYC_PART_CONTENT;
|
|
}
|
|
|
|
/**
|
|
* Sets a new buffer in the parser state struct with data to be parsed.
|
|
*
|
|
* This function does NOT copy the buffer. It will parse whatever is
|
|
* at the memory pointed to by buffer.
|
|
*
|
|
* @param state Pointer to the initialized state of the parser
|
|
* @param buffer pointer to the data that should be parsed
|
|
* @param length length of the data in bytes
|
|
* @see PsycString
|
|
*/
|
|
static inline void
|
|
psyc_parse_buffer_set (PsycParseState *state, char *buffer, size_t length)
|
|
{
|
|
state->buffer = (PsycString) {length, buffer};
|
|
state->cursor = 0;
|
|
|
|
if (state->flags & PSYC_PARSE_START_AT_CONTENT) {
|
|
state->contentlen = length;
|
|
state->contentlen_found = PSYC_TRUE;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Initializes the list state.
|
|
*/
|
|
static inline void
|
|
psyc_parse_list_state_init (PsycParseListState *state)
|
|
{
|
|
memset(state, 0, sizeof(PsycParseListState));
|
|
}
|
|
|
|
/**
|
|
* Sets a new buffer in the list parser state struct with data to be parsed.
|
|
*/
|
|
static inline void
|
|
psyc_parse_list_buffer_set (PsycParseListState *state, char *buffer, size_t length)
|
|
{
|
|
state->buffer = (PsycString) {length, buffer};
|
|
state->cursor = 0;
|
|
}
|
|
|
|
static inline void
|
|
psyc_parse_list_term_set (PsycParseListState *state, char term)
|
|
{
|
|
state->term = term;
|
|
state->term_set = PSYC_TRUE;
|
|
}
|
|
|
|
/**
|
|
* Initializes the table state.
|
|
*/
|
|
static inline void
|
|
psyc_parse_table_state_init (PsycParseTableState *state)
|
|
{
|
|
memset(state, 0, sizeof(PsycParseTableState));
|
|
}
|
|
|
|
/**
|
|
* Sets a new buffer in the list parser state struct with data to be parsed.
|
|
*/
|
|
static inline void
|
|
psyc_parse_table_buffer_set (PsycParseTableState *state, char *buffer, size_t length)
|
|
{
|
|
state->buffer = (PsycString) {length, buffer};
|
|
state->cursor = 0;
|
|
}
|
|
|
|
static inline size_t
|
|
psyc_parse_content_length (PsycParseState *state)
|
|
{
|
|
return state->contentlen;
|
|
}
|
|
|
|
static inline PsycBool
|
|
psyc_parse_content_length_found (PsycParseState *state)
|
|
{
|
|
return state->contentlen_found;
|
|
}
|
|
|
|
static inline size_t
|
|
psyc_parse_value_length (PsycParseState *state)
|
|
{
|
|
return state->valuelen;
|
|
}
|
|
|
|
static inline PsycBool
|
|
psyc_parse_value_length_found (PsycParseState *state)
|
|
{
|
|
return state->valuelen_found;
|
|
}
|
|
|
|
static inline size_t
|
|
psyc_parse_cursor (PsycParseState *state)
|
|
{
|
|
return state->cursor;
|
|
}
|
|
|
|
static inline size_t
|
|
psyc_parse_buffer_length (PsycParseState *state)
|
|
{
|
|
return state->buffer.length;
|
|
}
|
|
|
|
static inline size_t
|
|
psyc_parse_remaining_length (PsycParseState *state)
|
|
{
|
|
return state->buffer.length - state->cursor;
|
|
}
|
|
|
|
static inline const char *
|
|
psyc_parse_remaining_buffer (PsycParseState *state)
|
|
{
|
|
return state->buffer.data + state->cursor;
|
|
}
|
|
|
|
/**
|
|
* Parse PSYC packets.
|
|
*
|
|
* This function parses a full or partial PSYC packet while keeping parsing
|
|
* state in a state variable that you have to pass in every time, and returns
|
|
* whenever a modifier or the body is found. See PsycParseRC for the possible
|
|
* return codes. When it returns oper, name & value will point to the respective
|
|
* parts of the buffer, no memory allocation is done.
|
|
*
|
|
* @param state An initialized PsycParseState.
|
|
* @param oper In case of a modifier it will be set to the operator.
|
|
* @param name In case of a modifier it will point to the name,
|
|
* in case of the body it will point to the method.
|
|
* @param value In case of a modifier it will point to the value,
|
|
* in case of the body it will point to the data.
|
|
*/
|
|
#ifdef __INLINE_PSYC_PARSE
|
|
static inline
|
|
#endif
|
|
PsycParseRC
|
|
psyc_parse (PsycParseState *state, char *oper,
|
|
PsycString *name, PsycString *value);
|
|
|
|
/**
|
|
* List parser.
|
|
*
|
|
* This function parses a _list modifier value and returns one element a time
|
|
* while keeping parsing state in a state variable that you have to pass in
|
|
* every time. When it returns elem will point to the next element in value, no
|
|
* memory allocation is done.
|
|
*
|
|
* @param state An initialized PsycParseListState.
|
|
* @param elem It will point to the next element in the list.
|
|
*/
|
|
#ifdef __INLINE_PSYC_PARSE
|
|
static inline
|
|
#endif
|
|
PsycParseListRC
|
|
psyc_parse_list (PsycParseListState *state, PsycString *elem);
|
|
|
|
PsycParseTableRC
|
|
psyc_parse_table (PsycParseTableState *state, PsycString *elem);
|
|
|
|
static inline size_t
|
|
psyc_parse_int (const char *value, size_t len, int64_t *n)
|
|
{
|
|
size_t c = 0;
|
|
uint8_t neg = 0;
|
|
|
|
if (!value)
|
|
return c;
|
|
|
|
if (value[0] == '-')
|
|
neg = ++c;
|
|
|
|
*n = 0;
|
|
while (c < len && value[c] >= '0' && value[c] <= '9')
|
|
*n = 10 * *n + (value[c++] - '0');
|
|
|
|
if (c != len)
|
|
return c;
|
|
|
|
if (neg)
|
|
*n = 0 - *n;
|
|
|
|
return c;
|
|
}
|
|
|
|
static inline size_t
|
|
psyc_parse_uint (const char *value, size_t len, uint64_t *n)
|
|
{
|
|
size_t c = 0;
|
|
if (!value)
|
|
return c;
|
|
|
|
*n = 0;
|
|
while (c < len && value[c] >= '0' && value[c] <= '9')
|
|
*n = 10 * *n + (value[c++] - '0');
|
|
|
|
return c;
|
|
}
|
|
|
|
static inline size_t
|
|
psyc_parse_index (const char *value, size_t len, int64_t *n)
|
|
{
|
|
if (!value || len == 0 || value[0] != '#')
|
|
return 0;
|
|
return psyc_parse_int(value + 1, len, n) + 1;
|
|
}
|
|
|
|
/**
|
|
* Determines if the argument is a glyph.
|
|
* Glyphs are: : = + - ? !
|
|
*/
|
|
static inline PsycBool
|
|
psyc_is_glyph (char g)
|
|
{
|
|
switch (g) {
|
|
case ':':
|
|
case '=':
|
|
case '+':
|
|
case '-':
|
|
case '@':
|
|
case '?':
|
|
case '!':
|
|
return PSYC_TRUE;
|
|
default:
|
|
return PSYC_FALSE;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Determines if the argument is numeric.
|
|
*/
|
|
static inline char
|
|
psyc_is_numeric (char c)
|
|
{
|
|
return c >= '0' && c <= '9';
|
|
}
|
|
|
|
/**
|
|
* Determines if the argument is alphabetic.
|
|
*/
|
|
static inline char
|
|
psyc_is_alpha (char c)
|
|
{
|
|
return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z');
|
|
}
|
|
|
|
/**
|
|
* Determines if the argument is alphanumeric.
|
|
*/
|
|
static inline char
|
|
psyc_is_alpha_numeric (char c)
|
|
{
|
|
return psyc_is_alpha(c) || psyc_is_numeric(c);
|
|
}
|
|
|
|
/**
|
|
* Determines if the argument is a keyword character.
|
|
* Keyword characters are: alphanumeric and _
|
|
*/
|
|
static inline char
|
|
psyc_is_kw_char (char c)
|
|
{
|
|
return psyc_is_alpha_numeric(c) || c == '_';
|
|
}
|
|
|
|
/**
|
|
* Determines if the argument is a name character.
|
|
* Name characters are: see opaque_part in RFC 2396
|
|
*/
|
|
static inline char
|
|
psyc_is_name_char (char c)
|
|
{
|
|
return psyc_is_alpha(c) || (c >= '$' && c <= ';')
|
|
|| c == '_' || c == '!' || c == '?' || c == '=' || c == '@' || c == '~';
|
|
}
|
|
|
|
/**
|
|
* Determines if the argument is a hostname character.
|
|
* Hostname characters are: alphanumeric and -
|
|
*/
|
|
static inline char
|
|
psyc_is_host_char (char c)
|
|
{
|
|
return psyc_is_alpha_numeric(c) || c == '.' || c == '-';
|
|
}
|
|
|
|
/**
|
|
* Parse variable name or method name.
|
|
* It should contain one or more keyword characters.
|
|
* @return Number of characters parsed.
|
|
*/
|
|
static inline size_t
|
|
psyc_parse_keyword (const char *data, size_t len)
|
|
{
|
|
size_t c = 0;
|
|
while (c < len && psyc_is_kw_char(data[c++]));
|
|
return c > 0 ? c - 1 : 0;
|
|
}
|
|
|
|
/** @} */ // end of parse group
|
|
|
|
#endif
|