thodg/libgit2

diff --git a/examples/args.c b/examples/args.c
new file mode 100644
index 0000000..b228ae3
--- /dev/null
+++ b/examples/args.c
@@ -0,0 +1,170 @@
+#include "common.h"
+#include "args.h"
+
+size_t is_prefixed(const char *str, const char *pfx)
+{
+	size_t len = strlen(pfx);
+	return strncmp(str, pfx, len) ? 0 : len;
+}
+
+int optional_str_arg(
+	const char **out, struct args_info *args, const char *opt, const char *def)
+{
+	const char *found = args->argv[args->pos];
+	size_t len = is_prefixed(found, opt);
+
+	if (!len)
+		return 0;
+
+	if (!found[len]) {
+		if (args->pos + 1 == args->argc) {
+			*out = def;
+			return 1;
+		}
+		args->pos += 1;
+		*out = args->argv[args->pos];
+		return 1;
+	}
+
+	if (found[len] == '=') {
+		*out = found + len + 1;
+		return 1;
+	}
+
+	return 0;
+}
+
+int match_str_arg(
+	const char **out, struct args_info *args, const char *opt)
+{
+	const char *found = args->argv[args->pos];
+	size_t len = is_prefixed(found, opt);
+
+	if (!len)
+		return 0;
+
+	if (!found[len]) {
+		if (args->pos + 1 == args->argc)
+			fatal("expected value following argument", opt);
+		args->pos += 1;
+		*out = args->argv[args->pos];
+		return 1;
+	}
+
+	if (found[len] == '=') {
+		*out = found + len + 1;
+		return 1;
+	}
+
+	return 0;
+}
+
+static const char *match_numeric_arg(struct args_info *args, const char *opt)
+{
+	const char *found = args->argv[args->pos];
+	size_t len = is_prefixed(found, opt);
+
+	if (!len)
+		return NULL;
+
+	if (!found[len]) {
+		if (args->pos + 1 == args->argc)
+			fatal("expected numeric value following argument", opt);
+		args->pos += 1;
+		found = args->argv[args->pos];
+	} else {
+		found = found + len;
+		if (*found == '=')
+			found++;
+	}
+
+	return found;
+}
+
+int match_uint16_arg(
+	uint16_t *out, struct args_info *args, const char *opt)
+{
+	const char *found = match_numeric_arg(args, opt);
+	uint16_t val;
+	char *endptr = NULL;
+
+	if (!found)
+		return 0;
+
+	val = (uint16_t)strtoul(found, &endptr, 0);
+	if (!endptr || *endptr != '\0')
+		fatal("expected number after argument", opt);
+
+	if (out)
+		*out = val;
+	return 1;
+}
+
+int match_uint32_arg(
+	uint32_t *out, struct args_info *args, const char *opt)
+{
+	const char *found = match_numeric_arg(args, opt);
+	uint16_t val;
+	char *endptr = NULL;
+
+	if (!found)
+		return 0;
+
+	val = (uint32_t)strtoul(found, &endptr, 0);
+	if (!endptr || *endptr != '\0')
+		fatal("expected number after argument", opt);
+
+	if (out)
+		*out = val;
+	return 1;
+}
+
+static int match_int_internal(
+	int *out, const char *str, int allow_negative, const char *opt)
+{
+	char *endptr = NULL;
+	int	  val = (int)strtol(str, &endptr, 10);
+
+	if (!endptr || *endptr != '\0')
+		fatal("expected number", opt);
+	else if (val < 0 && !allow_negative)
+		fatal("negative values are not allowed", opt);
+
+	if (out)
+		*out = val;
+
+	return 1;
+}
+
+int match_bool_arg(int *out, struct args_info *args, const char *opt)
+{
+	const char *found = args->argv[args->pos];
+
+	if (!strcmp(found, opt)) {
+		*out = 1;
+		return 1;
+	}
+
+	if (!strncmp(found, "--no-", strlen("--no-")) &&
+	    !strcmp(found + strlen("--no-"), opt + 2)) {
+		*out = 0;
+		return 1;
+	}
+
+	*out = -1;
+	return 0;
+}
+
+int is_integer(int *out, const char *str, int allow_negative)
+{
+	return match_int_internal(out, str, allow_negative, NULL);
+}
+
+int match_int_arg(
+	int *out, struct args_info *args, const char *opt, int allow_negative)
+{
+	const char *found = match_numeric_arg(args, opt);
+	if (!found)
+		return 0;
+	return match_int_internal(out, found, allow_negative, opt);
+}
diff --git a/examples/args.h b/examples/args.h
new file mode 100644
index 0000000..b08a534
--- /dev/null
+++ b/examples/args.h
@@ -0,0 +1,79 @@
+#ifndef INCLUDE_examples_args_h__
+#define INCLUDE_examples_args_h__
+
+/**
+ * Argument-processing helper structure
+ */
+struct args_info {
+	int    argc;
+	char **argv;
+	int    pos;
+};
+#define ARGS_INFO_INIT { argc, argv, 0, 0 }
+#define ARGS_CURRENT(args) args->argv[args->pos]
+
+/**
+ * Check if a string has the given prefix.  Returns 0 if not prefixed
+ * or the length of the prefix if it is.
+ */
+extern size_t is_prefixed(const char *str, const char *pfx);
+
+/**
+ * Match an integer string, returning 1 if matched, 0 if not.
+ */
+extern int is_integer(int *out, const char *str, int allow_negative);
+
+/**
+ * Check current `args` entry against `opt` string.  If it matches
+ * exactly, take the next arg as a string; if it matches as a prefix with
+ * an equal sign, take the remainder as a string; if value not supplied,
+ * default value `def` will be given. otherwise return 0.
+ */
+extern int optional_str_arg(
+	const char **out, struct args_info *args, const char *opt, const char *def);
+
+/**
+ * Check current `args` entry against `opt` string.  If it matches
+ * exactly, take the next arg as a string; if it matches as a prefix with
+ * an equal sign, take the remainder as a string; otherwise return 0.
+ */
+extern int match_str_arg(
+	const char **out, struct args_info *args, const char *opt);
+
+/**
+ * Check current `args` entry against `opt` string parsing as uint16.  If
+ * `opt` matches exactly, take the next arg as a uint16_t value; if `opt`
+ * is a prefix (equal sign optional), take the remainder of the arg as a
+ * uint16_t value; otherwise return 0.
+ */
+extern int match_uint16_arg(
+	uint16_t *out, struct args_info *args, const char *opt);
+
+/**
+ * Check current `args` entry against `opt` string parsing as uint32.  If
+ * `opt` matches exactly, take the next arg as a uint16_t value; if `opt`
+ * is a prefix (equal sign optional), take the remainder of the arg as a
+ * uint32_t value; otherwise return 0.
+ */
+extern int match_uint32_arg(
+	uint32_t *out, struct args_info *args, const char *opt);
+
+/**
+ * Check current `args` entry against `opt` string parsing as int.  If
+ * `opt` matches exactly, take the next arg as an int value; if it matches
+ * as a prefix (equal sign optional), take the remainder of the arg as a
+ * int value; otherwise return 0.
+ */
+extern int match_int_arg(
+	int *out, struct args_info *args, const char *opt, int allow_negative);
+
+/**
+ * Check current `args` entry against a "bool" `opt` (ie. --[no-]progress).
+ * If `opt` matches positively, out will be set to 1, or if `opt` matches
+ * negatively, out will be set to 0, and in both cases 1 will be returned.
+ * If neither the positive or the negative form of opt matched, out will be -1,
+ * and 0 will be returned.
+ */
+extern int match_bool_arg(int *out, struct args_info *args, const char *opt);
+
+#endif
diff --git a/examples/common.c b/examples/common.c
index d243785..30f6cdc 100644
--- a/examples/common.c
+++ b/examples/common.c
@@ -53,174 +53,6 @@ void fatal(const char *message, const char *extra)
 	exit(1);
 }
 
-size_t is_prefixed(const char *str, const char *pfx)
-{
-	size_t len = strlen(pfx);
-	return strncmp(str, pfx, len) ? 0 : len;
-}
-
-int optional_str_arg(
-	const char **out, struct args_info *args, const char *opt, const char *def)
-{
-	const char *found = args->argv[args->pos];
-	size_t len = is_prefixed(found, opt);
-
-	if (!len)
-		return 0;
-
-	if (!found[len]) {
-		if (args->pos + 1 == args->argc) {
-			*out = def;
-			return 1;
-		}
-		args->pos += 1;
-		*out = args->argv[args->pos];
-		return 1;
-	}
-
-	if (found[len] == '=') {
-		*out = found + len + 1;
-		return 1;
-	}
-
-	return 0;
-}
-
-int match_str_arg(
-	const char **out, struct args_info *args, const char *opt)
-{
-	const char *found = args->argv[args->pos];
-	size_t len = is_prefixed(found, opt);
-
-	if (!len)
-		return 0;
-
-	if (!found[len]) {
-		if (args->pos + 1 == args->argc)
-			fatal("expected value following argument", opt);
-		args->pos += 1;
-		*out = args->argv[args->pos];
-		return 1;
-	}
-
-	if (found[len] == '=') {
-		*out = found + len + 1;
-		return 1;
-	}
-
-	return 0;
-}
-
-static const char *match_numeric_arg(struct args_info *args, const char *opt)
-{
-	const char *found = args->argv[args->pos];
-	size_t len = is_prefixed(found, opt);
-
-	if (!len)
-		return NULL;
-
-	if (!found[len]) {
-		if (args->pos + 1 == args->argc)
-			fatal("expected numeric value following argument", opt);
-		args->pos += 1;
-		found = args->argv[args->pos];
-	} else {
-		found = found + len;
-		if (*found == '=')
-			found++;
-	}
-
-	return found;
-}
-
-int match_uint16_arg(
-	uint16_t *out, struct args_info *args, const char *opt)
-{
-	const char *found = match_numeric_arg(args, opt);
-	uint16_t val;
-	char *endptr = NULL;
-
-	if (!found)
-		return 0;
-
-	val = (uint16_t)strtoul(found, &endptr, 0);
-	if (!endptr || *endptr != '\0')
-		fatal("expected number after argument", opt);
-
-	if (out)
-		*out = val;
-	return 1;
-}
-
-int match_uint32_arg(
-	uint32_t *out, struct args_info *args, const char *opt)
-{
-	const char *found = match_numeric_arg(args, opt);
-	uint16_t val;
-	char *endptr = NULL;
-
-	if (!found)
-		return 0;
-
-	val = (uint32_t)strtoul(found, &endptr, 0);
-	if (!endptr || *endptr != '\0')
-		fatal("expected number after argument", opt);
-
-	if (out)
-		*out = val;
-	return 1;
-}
-
-static int match_int_internal(
-	int *out, const char *str, int allow_negative, const char *opt)
-{
-	char *endptr = NULL;
-	int	  val = (int)strtol(str, &endptr, 10);
-
-	if (!endptr || *endptr != '\0')
-		fatal("expected number", opt);
-	else if (val < 0 && !allow_negative)
-		fatal("negative values are not allowed", opt);
-
-	if (out)
-		*out = val;
-
-	return 1;
-}
-
-int match_bool_arg(int *out, struct args_info *args, const char *opt)
-{
-	const char *found = args->argv[args->pos];
-
-	if (!strcmp(found, opt)) {
-		*out = 1;
-		return 1;
-	}
-
-	if (!strncmp(found, "--no-", strlen("--no-")) &&
-	    !strcmp(found + strlen("--no-"), opt + 2)) {
-		*out = 0;
-		return 1;
-	}
-
-	*out = -1;
-	return 0;
-}
-
-int is_integer(int *out, const char *str, int allow_negative)
-{
-	return match_int_internal(out, str, allow_negative, NULL);
-}
-
-int match_int_arg(
-	int *out, struct args_info *args, const char *opt, int allow_negative)
-{
-	const char *found = match_numeric_arg(args, opt);
-	if (!found)
-		return 0;
-	return match_int_internal(out, found, allow_negative, opt);
-}
-
 int diff_output(
 	const git_diff_delta *d,
 	const git_diff_hunk *h,
diff --git a/examples/common.h b/examples/common.h
index 3657e53..5a029b4 100644
--- a/examples/common.h
+++ b/examples/common.h
@@ -52,6 +52,8 @@
 #define ARRAY_SIZE(x) (sizeof(x)/sizeof(*x))
 #define UNUSED(x) (void)(x)
 
+#include "args.h"
+
 extern int lg2_add(git_repository *repo, int argc, char **argv);
 extern int lg2_blame(git_repository *repo, int argc, char **argv);
 extern int lg2_cat_file(git_repository *repo, int argc, char **argv);
@@ -97,77 +99,6 @@ extern char *read_file(const char *path);
 extern void fatal(const char *message, const char *extra);
 
 /**
- * Check if a string has the given prefix.  Returns 0 if not prefixed
- * or the length of the prefix if it is.
- */
-extern size_t is_prefixed(const char *str, const char *pfx);
-
-/**
- * Match an integer string, returning 1 if matched, 0 if not.
- */
-extern int is_integer(int *out, const char *str, int allow_negative);
-
-struct args_info {
-	int    argc;
-	char **argv;
-	int    pos;
-};
-#define ARGS_INFO_INIT { argc, argv, 0 }
-
-/**
- * Check current `args` entry against `opt` string.  If it matches
- * exactly, take the next arg as a string; if it matches as a prefix with
- * an equal sign, take the remainder as a string; if value not supplied,
- * default value `def` will be given. otherwise return 0.
- */
-extern int optional_str_arg(
-	const char **out, struct args_info *args, const char *opt, const char *def);
-
-/**
- * Check current `args` entry against `opt` string.  If it matches
- * exactly, take the next arg as a string; if it matches as a prefix with
- * an equal sign, take the remainder as a string; otherwise return 0.
- */
-extern int match_str_arg(
-	const char **out, struct args_info *args, const char *opt);
-
-/**
- * Check current `args` entry against `opt` string parsing as uint16.  If
- * `opt` matches exactly, take the next arg as a uint16_t value; if `opt`
- * is a prefix (equal sign optional), take the remainder of the arg as a
- * uint16_t value; otherwise return 0.
- */
-extern int match_uint16_arg(
-	uint16_t *out, struct args_info *args, const char *opt);
-
-/**
- * Check current `args` entry against `opt` string parsing as uint32.  If
- * `opt` matches exactly, take the next arg as a uint16_t value; if `opt`
- * is a prefix (equal sign optional), take the remainder of the arg as a
- * uint32_t value; otherwise return 0.
- */
-extern int match_uint32_arg(
-	uint32_t *out, struct args_info *args, const char *opt);
-
-/**
- * Check current `args` entry against `opt` string parsing as int.  If
- * `opt` matches exactly, take the next arg as an int value; if it matches
- * as a prefix (equal sign optional), take the remainder of the arg as a
- * int value; otherwise return 0.
- */
-extern int match_int_arg(
-	int *out, struct args_info *args, const char *opt, int allow_negative);
-
-/**
- * Check current `args` entry against a "bool" `opt` (ie. --[no-]progress).
- * If `opt` matches positively, out will be set to 1, or if `opt` matches
- * negatively, out will be set to 0, and in both cases 1 will be returned.
- * If neither the positive or the negative form of opt matched, out will be -1,
- * and 0 will be returned.
- */
-extern int match_bool_arg(int *out, struct args_info *args, const char *opt);
-
-/**
  * Basic output function for plain text diff output
  * Pass `FILE*` such as `stdout` or `stderr` as payload (or NULL == `stdout`)
  */