[PATCH/RFC] credentials helpers+remote helpers

@@ -31,6 +31,7 @@
 /git-commit-tree
 /git-config
 /git-count-objects
+/git-credential
 /git-credential-cache
 /git-credential-cache--daemon
 /git-credential-store

@@ -0,0 +1,70 @@
+git-credential(7)
+=================
+
+NAME
+----
+git-credential - Providing and storing user credentials to git
+
+SYNOPSIS
+--------
+------------------
+git credential [fill|approve|reject]
+
+------------------
+
+DESCRIPTION
+-----------
+
+Git-credential permits to save username, password, host, path and protocol.
+When you invoke git-credential, you can ask for a password, using the command
+'git credential fill'.
+Providing them by STDIN: 
+
+		username=admin\n 
+		protocol=[http|https]\n
+		host=localhost\n
+		path=/dir\n\n
+
+-If git-credential system, have the password already stored
+git-credential will answer by STDOUT:
+	
+		username=admin\n
+		password=*****\n
+
+-If it is not stored, git-credential will ask you to enter 
+the password:
+		
+		> Password for '[http|https]admin@localhost':
+
+Then if password is correct, you can store using command
+'git crendential approve' providing the structure, by STDIN.
+
+		username=admin\n 
+		password=*****\n
+		protocol=[http|https]\n
+		host=localhost\n
+		path=/dir\n\n
+
+If the password is refused, you can delete using command
+'git credential reject' providing the same structure.
+
+
+REQUESTING CREDENTIALS
+----------------------
+
+1. The 'git credential fill' makes the structure:
+		username=foo
+		password=****
+		protocol=[http|https]
+		localhost=url
+		path=/direction
+
+   with this structure it will be able to save your
+   credentials, and if the credential is allready stored,
+   it will fill the password.
+
+2. Then 'git credential approve' to store them.
+
+3. Otherwise, if the credential is not correct you can do
+  'git credential reject' to delete the credential.
+-------------------------------------------

@@ -827,6 +827,7 @@ BUILTIN_OBJS += builtin/commit-tree.o
 BUILTIN_OBJS += builtin/commit.o
 BUILTIN_OBJS += builtin/config.o
 BUILTIN_OBJS += builtin/count-objects.o
+BUILTIN_OBJS += builtin/credential.o
 BUILTIN_OBJS += builtin/describe.o
 BUILTIN_OBJS += builtin/diff-files.o
 BUILTIN_OBJS += builtin/diff-index.o

@@ -66,6 +66,7 @@ extern int cmd_commit(int argc, const char **argv, const char *prefix);
 extern int cmd_commit_tree(int argc, const char **argv, const char *prefix);
 extern int cmd_config(int argc, const char **argv, const char *prefix);
 extern int cmd_count_objects(int argc, const char **argv, const char *prefix);
+extern int cmd_credential(int argc, const char **argv, const char *prefix);
 extern int cmd_describe(int argc, const char **argv, const char *prefix);
 extern int cmd_diff_files(int argc, const char **argv, const char *prefix);
 extern int cmd_diff_index(int argc, const char **argv, const char *prefix);

@@ -0,0 +1,40 @@
+#include <stdio.h>
+#include "cache.h"
+#include "credential.h"
+#include "string-list.h"
+
+static const char usage_msg[] =
+"credential <fill|approve|reject> [helper...]";
+
+void cmd_credential (int argc, char **argv, const char *prefix){
+	const char *op;
+	struct credential c = CREDENTIAL_INIT;
+	int i;
+
+	op = argv[1];
+	if (!op)
+		usage(usage_msg);
+
+	for (i = 2; i < argc; i++)
+		string_list_append(&c.helpers, argv[i]);
+
+	if (credential_read(&c, stdin) < 0)
+		die("unable to read credential from stdin");
+
+	if (!strcmp(op, "fill")) {
+		credential_fill(&c);
+		if (c.username)
+			printf("username=%s\n", c.username);
+		if (c.password)
+			printf("password=%s\n", c.password);
+	}
+	else if (!strcmp(op, "approve")) {
+		credential_approve(&c);
+	}
+	else if (!strcmp(op, "reject")) {
+		credential_reject(&c);
+	}
+	else
+		usage(usage_msg);
+}
+

@@ -353,6 +353,7 @@ static void handle_internal_command(int argc, const char **argv)
 		{ "commit-tree", cmd_commit_tree, RUN_SETUP },
 		{ "config", cmd_config, RUN_SETUP_GENTLY },
 		{ "count-objects", cmd_count_objects, RUN_SETUP },
+		{ "credential", cmd_credential, RUN_SETUP },
 		{ "describe", cmd_describe, RUN_SETUP },
 		{ "diff", cmd_diff },
 		{ "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE },