[RFC/PATCH 2/3] wildmatch: add interface for precompiling wildmatch() patterns

From: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Date: Jun 22, 2017, 21:38 UTC
Message-ID: <20170622213810.14785-3-avarab@gmail.com>
In-Reply-To: <20170622213810.14785-1-avarab@gmail.com>

Add the scaffolding necessary for precompiling wildmatch() patterns.

There is currently no point in doing this with the wildmatch() function we have now, since it can't make any use of precompiling the pattern.

But adding this interface and making use of it will make it easy to refactor the wildmatch() function to e.g. parse the pattern into opcode as the BSD glob() implementation does, or to drop an alternate wildmatch() backend in which trades parsing slowness for faster matching.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 wildmatch.c | 20 ++++++++++++++++++++
 wildmatch.h |  9 +++++++++
 2 files changed, 29 insertions(+)

diff --git a/wildmatch.c b/wildmatch.c
index d074c1be10..ba6a92a393 100644
--- a/wildmatch.c
+++ b/wildmatch.c
@@ -276,3 +276,23 @@ int wildmatch(const char *pattern, const char *text, unsigned int flags)
 {
 	return dowild((const uchar*)pattern, (const uchar*)text, flags);
 }
+
+struct wildmatch_compiled *wildmatch_compile(const char *pattern, unsigned int flags)
+{
+	struct wildmatch_compiled *code = xmalloc(sizeof(struct wildmatch_compiled));
+	code->pattern = xstrdup(pattern);
+	code->flags = flags;
+
+	return code;
+}
+
+int wildmatch_match(struct wildmatch_compiled *code, const char *text)
+{
+	return wildmatch(code->pattern, text, code->flags);
+}
+
+void wildmatch_free(struct wildmatch_compiled *code)
+{
+	free((void *)code->pattern);
+	free(code);
+}
diff --git a/wildmatch.h b/wildmatch.h
index b8c826aa68..6156d46a33 100644
--- a/wildmatch.h
+++ b/wildmatch.h
@@ -10,5 +10,14 @@
 #define WM_ABORT_ALL -1
 #define WM_ABORT_TO_STARSTAR -2
 
+struct wildmatch_compiled {
+	const char *pattern;
+	unsigned int flags;
+};
+
 int wildmatch(const char *pattern, const char *text, unsigned int flags);
+struct wildmatch_compiled *wildmatch_compile(const char *pattern, unsigned int flags);
+int wildmatch_match(struct wildmatch_compiled *code, const char *text);
+void wildmatch_free(struct wildmatch_compiled *code);
+
 #endif

-- 
2.13.1.611.g7e3b11ae1