Function hyperscan_sys::hs_expression_ext_info
source · [−]pub unsafe extern "C" fn hs_expression_ext_info(
expression: *const c_char,
flags: c_uint,
ext: *const hs_expr_ext_t,
info: *mut *mut hs_expr_info_t,
error: *mut *mut hs_compile_error_t
) -> hs_error_t
Expand description
Utility function providing information about a regular expression, with extended parameter support. The information provided in @ref hs_expr_info_t includes the minimum and maximum width of a pattern match.
Note: successful analysis of an expression with this function does not imply that compilation of the same expression (via @ref hs_compile(), @ref hs_compile_multi() or @ref hs_compile_ext_multi()) would succeed. This function may return @ref HS_SUCCESS for regular expressions that Hyperscan cannot compile.
Note: some per-pattern flags (such as @ref HS_FLAG_ALLOWEMPTY, @ref HS_FLAG_SOM_LEFTMOST) are accepted by this call, but as they do not affect the properties returned in the @ref hs_expr_info_t structure, they will not affect the outcome of this function.
@param expression
The NULL-terminated expression to parse. Note that this string must
represent ONLY the pattern to be matched, with no delimiters or flags;
any global flags should be specified with the @p flags argument. For
example, the expression /abc?def/i
should be compiled by providing
abc?def
as the @p expression, and @ref HS_FLAG_CASELESS as the @a
flags.
@param flags
Flags which modify the behaviour of the expression. Multiple flags may
be used by ORing them together. Valid values are:
- HS_FLAG_CASELESS - Matching will be performed case-insensitively.
- HS_FLAG_DOTALL - Matching a .
will not exclude newlines.
- HS_FLAG_MULTILINE - ^
and $
anchors match any newlines in data.
- HS_FLAG_SINGLEMATCH - Only one match will be generated by the
expression per stream.
- HS_FLAG_ALLOWEMPTY - Allow expressions which can match against an
empty string, such as .*
.
- HS_FLAG_UTF8 - Treat this pattern as a sequence of UTF-8 characters.
- HS_FLAG_UCP - Use Unicode properties for character classes.
- HS_FLAG_PREFILTER - Compile pattern in prefiltering mode.
- HS_FLAG_SOM_LEFTMOST - Report the leftmost start of match offset
when a match is found.
- HS_FLAG_COMBINATION - Parse the expression in logical combination
syntax.
- HS_FLAG_QUIET - Ignore match reporting for this expression. Used for
the sub-expressions in logical combinations.
@param ext A pointer to a filled @ref hs_expr_ext_t structure that defines extended behaviour for this pattern. NULL may be specified if no extended parameters are needed.
@param info On success, a pointer to the pattern information will be returned in this parameter, or NULL on failure. This structure is allocated using the allocator supplied in @ref hs_set_allocator() (or malloc() if no allocator was set) and should be freed by the caller.
@param error If the call fails, a pointer to a @ref hs_compile_error_t will be returned, providing details of the error condition. The caller is responsible for deallocating the buffer using the @ref hs_free_compile_error() function.
@return @ref HS_SUCCESS is returned on successful compilation; @ref HS_COMPILER_ERROR on failure, with details provided in the error parameter.