1 files changed, 97 insertions, 0 deletions
diff --git a/src/util/regexp.h b/src/util/regexp.h
new file mode 100644
index 000000000..d0862b107
--- /dev/null
+++ b/src/util/regexp.h
@@ -0,0 +1,97 @@
+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+
+#ifndef INCLUDE_regexp_h__
+#define INCLUDE_regexp_h__
+
+#include "git2_util.h"
+
+#if defined(GIT_REGEX_BUILTIN) || defined(GIT_REGEX_PCRE)
+# include "pcre.h"
+typedef pcre *git_regexp;
+# define GIT_REGEX_INIT NULL
+#elif defined(GIT_REGEX_PCRE2)
+# define PCRE2_CODE_UNIT_WIDTH 8
+# include <pcre2.h>
+typedef pcre2_code *git_regexp;
+# define GIT_REGEX_INIT NULL
+#elif defined(GIT_REGEX_REGCOMP) || defined(GIT_REGEX_REGCOMP_L)
+# include <regex.h>
+typedef regex_t git_regexp;
+# define GIT_REGEX_INIT { 0 }
+#else
+# error "No regex backend"
+#endif
+
+/** Options supported by @git_regexp_compile. */
+typedef enum {
+	/** Enable case-insensitive matching */
+	GIT_REGEXP_ICASE = (1 << 0)
+} git_regexp_flags_t;
+
+/** Structure containing information about regular expression matching groups */
+typedef struct {
+	/** Start of the given match. -1 if the group didn't match anything */
+	ssize_t start;
+	/** End of the given match. -1 if the group didn't match anything */
+	ssize_t end;
+} git_regmatch;
+
+/**
+ * Compile a regular expression. The compiled expression needs to
+ * be cleaned up afterwards with `git_regexp_dispose`.
+ *
+ * @param r Pointer to the storage where to initialize the regular expression.
+ * @param pattern The pattern that shall be compiled.
+ * @param flags Flags to alter how the pattern shall be handled.
+ *              0 for defaults, otherwise see @git_regexp_flags_t.
+ * @return 0 on success, otherwise a negative return value.
+ */
+int git_regexp_compile(git_regexp *r, const char *pattern, int flags);
+
+/**
+ * Free memory associated with the regular expression
+ *
+ * @param r The regular expression structure to dispose.
+ */
+void git_regexp_dispose(git_regexp *r);
+
+/**
+ * Test whether a given string matches a compiled regular
+ * expression.
+ *
+ * @param r Compiled regular expression.
+ * @param string String to match against the regular expression.
+ * @return 0 if the string matches, a negative error code
+ *         otherwise. GIT_ENOTFOUND if no match was found,
+ *         GIT_EINVALIDSPEC if the regular expression matching
+ *         was invalid.
+ */
+int git_regexp_match(const git_regexp *r, const char *string);
+
+/**
+ * Search for matches inside of a given string.
+ *
+ * Given a regular expression with capturing groups, this
+ * function will populate provided @git_regmatch structures with
+ * offsets for each of the given matches. Non-matching groups
+ * will have start and end values of the respective @git_regmatch
+ * structure set to -1.
+ *
+ * @param r Compiled regular expression.
+ * @param string String to match against the regular expression.
+ * @param nmatches Number of @git_regmatch structures provided by
+ *                 the user.
+ * @param matches Pointer to an array of @git_regmatch structures.
+ * @return 0 if the string matches, a negative error code
+ *         otherwise. GIT_ENOTFOUND if no match was found,
+ *         GIT_EINVALIDSPEC if the regular expression matching
+ *         was invalid.
+ */
+int git_regexp_search(const git_regexp *r, const char *string, size_t nmatches, git_regmatch *matches);
+
+#endif