Glob-style pattern matching

Glob-style pattern matching — matches strings against patterns containing '*' (wildcard) and '?' (joker)

Synopsis

#include <glib.h>

                    GPatternSpec;
GPatternSpec *      g_pattern_spec_new                  (const gchar *pattern);
void                g_pattern_spec_free                 (GPatternSpec *pspec);
gboolean            g_pattern_spec_equal                (GPatternSpec *pspec1,
                                                         GPatternSpec *pspec2);
gboolean            g_pattern_match                     (GPatternSpec *pspec,
                                                         guint string_length,
                                                         const gchar *string,
                                                         const gchar *string_reversed);
gboolean            g_pattern_match_string              (GPatternSpec *pspec,
                                                         const gchar *string);
gboolean            g_pattern_match_simple              (const gchar *pattern,
                                                         const gchar *string);

Description

The g_pattern_match* functions match a string against a pattern containing '*' and '?' wildcards with similar semantics as the standard glob() function: '*' matches an arbitrary, possibly empty, string, '?' matches an arbitrary character.

Note that in contrast to glob(), the '/' character can be matched by the wildcards, there are no '[...]' character ranges and '*' and '?' can not be escaped to include them literally in a pattern.

When multiple strings must be matched against the same pattern, it is better to compile the pattern to a GPatternSpec using g_pattern_spec_new() and use g_pattern_match_string() instead of g_pattern_match_simple(). This avoids the overhead of repeated pattern compilation.

Details

GPatternSpec

typedef struct _GPatternSpec GPatternSpec;

A GPatternSpec is the 'compiled' form of a pattern. This structure is opaque and its fields cannot be accessed directly.


g_pattern_spec_new ()

GPatternSpec *      g_pattern_spec_new                  (const gchar *pattern);

Compiles a pattern to a GPatternSpec.

pattern :

a zero-terminated UTF-8 encoded string

Returns :

a newly-allocated GPatternSpec

g_pattern_spec_free ()

void                g_pattern_spec_free                 (GPatternSpec *pspec);

Frees the memory allocated for the GPatternSpec.

pspec :

a GPatternSpec

g_pattern_spec_equal ()

gboolean            g_pattern_spec_equal                (GPatternSpec *pspec1,
                                                         GPatternSpec *pspec2);

Compares two compiled pattern specs and returns whether they will match the same set of strings.

pspec1 :

a GPatternSpec

pspec2 :

another GPatternSpec

Returns :

Whether the compiled patterns are equal

g_pattern_match ()

gboolean            g_pattern_match                     (GPatternSpec *pspec,
                                                         guint string_length,
                                                         const gchar *string,
                                                         const gchar *string_reversed);

Matches a string against a compiled pattern. Passing the correct length of the string given is mandatory. The reversed string can be omitted by passing NULL, this is more efficient if the reversed version of the string to be matched is not at hand, as g_pattern_match() will only construct it if the compiled pattern requires reverse matches.

Note that, if the user code will (possibly) match a string against a multitude of patterns containing wildcards, chances are high that some patterns will require a reversed string. In this case, it's more efficient to provide the reversed string to avoid multiple constructions thereof in the various calls to g_pattern_match().

Note also that the reverse of a UTF-8 encoded string can in general not be obtained by g_strreverse(). This works only if the string doesn't contain any multibyte characters. GLib offers the g_utf8_strreverse() function to reverse UTF-8 encoded strings.

pspec :

a GPatternSpec

string_length :

the length of string (in bytes, i.e. strlen(), not g_utf8_strlen())

string :

the UTF-8 encoded string to match

string_reversed :

the reverse of string or NULL

Returns :

TRUE if string matches pspec

g_pattern_match_string ()

gboolean            g_pattern_match_string              (GPatternSpec *pspec,
                                                         const gchar *string);

Matches a string against a compiled pattern. If the string is to be matched against more than one pattern, consider using g_pattern_match() instead while supplying the reversed string.

pspec :

a GPatternSpec

string :

the UTF-8 encoded string to match

Returns :

TRUE if string matches pspec

g_pattern_match_simple ()

gboolean            g_pattern_match_simple              (const gchar *pattern,
                                                         const gchar *string);

Matches a string against a pattern given as a string. If this function is to be called in a loop, it's more efficient to compile the pattern once with g_pattern_spec_new() and call g_pattern_match_string() repeatedly.

pattern :

the UTF-8 encoded pattern

string :

the UTF-8 encoded string to match

Returns :

TRUE if string matches pspec