[PATCH 1/4] Add a simple option parser for use by builtin-commit.c.

["Kristian Høgsberg" <krh@redhat.com>]

Signed-off-by: Kristian Høgsberg <krh@redhat.com>
---
 Makefile        |    2 +-
 parse-options.c |   74 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 parse-options.h |   29 +++++++++++++++++++++
 3 files changed, 104 insertions(+), 1 deletions(-)
 create mode 100644 parse-options.c
 create mode 100644 parse-options.h

diff --git a/Makefile b/Makefile
index 62bdac6..d90e959 100644
--- a/Makefile
+++ b/Makefile
@@ -310,7 +310,7 @@ LIB_OBJS = \
 	alloc.o merge-file.o path-list.o help.o unpack-trees.o $(DIFF_OBJS) \
 	color.o wt-status.o archive-zip.o archive-tar.o shallow.o utf8.o \
 	convert.o attr.o decorate.o progress.o mailmap.o symlinks.o remote.o \
-	transport.o bundle.o
+	transport.o bundle.o parse-options.o
 
 BUILTIN_OBJS = \
 	builtin-add.o \
diff --git a/parse-options.c b/parse-options.c
new file mode 100644
index 0000000..2fb30cd
--- /dev/null
+++ b/parse-options.c
@@ -0,0 +1,74 @@
+#include "git-compat-util.h"
+#include "parse-options.h"
+
+int parse_options(const char ***argv,
+		  struct option *options, int count,
+		  const char *usage_string)
+{
+	const char *value, *eq;
+	int i;
+
+	if (**argv == NULL)
+		return 0;
+	if ((**argv)[0] != '-')
+		return 0;
+	if (!strcmp(**argv, "--"))
+		return 0;
+
+	value = NULL;
+	for (i = 0; i < count; i++) {
+		if ((**argv)[1] == '-') {
+			if (!prefixcmp(options[i].long_name, **argv + 2)) {
+				if (options[i].type != OPTION_BOOLEAN)
+					value = *++(*argv);
+				goto match;
+			}
+
+			eq = strchr(**argv + 2, '=');
+			if (eq && options[i].type != OPTION_BOOLEAN &&
+			    !strncmp(**argv + 2,
+				     options[i].long_name, eq - **argv - 2)) {
+				value = eq + 1;
+				goto match;
+			}
+		}
+
+		if ((**argv)[1] == options[i].short_name) {
+			if ((**argv)[2] == '\0') {
+				if (options[i].type != OPTION_BOOLEAN)
+					value = *++(*argv);
+				goto match;
+			}
+
+			if (options[i].type != OPTION_BOOLEAN) {
+				value = **argv + 2;
+				goto match;
+			}
+		}
+	}
+
+	usage(usage_string);
+
+ match:
+	switch (options[i].type) {
+	case OPTION_BOOLEAN:
+		*(int *)options[i].value = 1;
+		break;
+	case OPTION_STRING:
+		if (value == NULL)
+			die("option %s requires a value.", (*argv)[-1]);
+		*(const char **)options[i].value = value;
+		break;
+	case OPTION_INTEGER:
+		if (value == NULL)
+			die("option %s requires a value.", (*argv)[-1]);
+		*(int *)options[i].value = atoi(value);
+		break;
+	default:
+		assert(0);
+	}
+
+	(*argv)++;
+
+	return 1;
+}
diff --git a/parse-options.h b/parse-options.h
new file mode 100644
index 0000000..39399c3
--- /dev/null
+++ b/parse-options.h
@@ -0,0 +1,29 @@
+#ifndef PARSE_OPTIONS_H
+#define PARSE_OPTIONS_H
+
+enum option_type {
+    OPTION_BOOLEAN,
+    OPTION_STRING,
+    OPTION_INTEGER,
+    OPTION_LAST,
+};
+
+struct option {
+    enum option_type type;
+    const char *long_name;
+    char short_name;
+    void *value;
+};
+
+/* Parse the given options against the list of known options.  The
+ * order of the option structs matters, in that ambiguous
+ * abbreviations (eg, --in could be short for --include or
+ * --interactive) are matched by the first option that share the
+ * prefix.
+ */
+
+extern int parse_options(const char ***argv,
+			 struct option *options, int count,
+			 const char *usage_string);
+
+#endif
-- 
1.5.2.GIT