Merge branch 'jk/git-prompt'

* jk/git-prompt:
  contrib: add credential helper for OS X Keychain
  Makefile: OS X has /dev/tty
  Makefile: linux has /dev/tty
  credential: use git_prompt instead of git_getpass
  prompt: use git_terminal_prompt
  add generic terminal prompt function
  refactor git_getpass into generic prompt function
  move git_getpass to its own source file
  imap-send: don't check return value of git_getpass
  imap-send: avoid buffer overflow

Conflicts:
	Makefile

12 files changed, 374 insertions, 60 deletions

diff --git a/Makefile b/Makefile
index 9470a1034..a78240930 100644
--- a/Makefile
+++ b/Makefile
@@ -245,6 +245,9 @@ all::
 #
 # Define NO_REGEX if you have no or inferior regex support in your C library.
 #
+# Define HAVE_DEV_TTY if your system can open /dev/tty to interact with the
+# user.
+#
 # Define GETTEXT_POISON if you are debugging the choice of strings marked
 # for translation.  In a GETTEXT_POISON build, you can turn all strings marked
 # for translation into gibberish by setting the GIT_GETTEXT_POISON variable
@@ -543,6 +546,7 @@ LIB_H += compat/bswap.h
 LIB_H += compat/cygwin.h
 LIB_H += compat/mingw.h
 LIB_H += compat/obstack.h
+LIB_H += compat/terminal.h
 LIB_H += compat/win32/pthread.h
 LIB_H += compat/win32/syslog.h
 LIB_H += compat/win32/poll.h
@@ -585,6 +589,7 @@ LIB_H += parse-options.h
 LIB_H += patch-ids.h
 LIB_H += pkt-line.h
 LIB_H += progress.h
+LIB_H += prompt.h
 LIB_H += quote.h
 LIB_H += reflog-walk.h
 LIB_H += refs.h
@@ -632,6 +637,7 @@ LIB_OBJS += color.o
 LIB_OBJS += combine-diff.o
 LIB_OBJS += commit.o
 LIB_OBJS += compat/obstack.o
+LIB_OBJS += compat/terminal.o
 LIB_OBJS += config.o
 LIB_OBJS += connect.o
 LIB_OBJS += connected.o
@@ -694,6 +700,7 @@ LIB_OBJS += pkt-line.o
 LIB_OBJS += preload-index.o
 LIB_OBJS += pretty.o
 LIB_OBJS += progress.o
+LIB_OBJS += prompt.o
 LIB_OBJS += quote.o
 LIB_OBJS += reachable.o
 LIB_OBJS += read-cache.o
@@ -856,6 +863,7 @@ ifeq ($(uname_S),Linux)
 	NO_MKSTEMPS = YesPlease
 	HAVE_PATHS_H = YesPlease
 	LIBC_CONTAINS_LIBINTL = YesPlease
+	HAVE_DEV_TTY = YesPlease
 endif
 ifeq ($(uname_S),GNU/kFreeBSD)
 	NO_STRLCPY = YesPlease
@@ -917,6 +925,7 @@ ifeq ($(uname_S),Darwin)
 	endif
 	NO_MEMMEM = YesPlease
 	USE_ST_TIMESPEC = YesPlease
+	HAVE_DEV_TTY = YesPlease
 endif
 ifeq ($(uname_S),SunOS)
 	NEEDS_SOCKET = YesPlease
@@ -1685,6 +1694,10 @@ ifdef HAVE_LIBCHARSET_H
 	BASIC_CFLAGS += -DHAVE_LIBCHARSET_H
 endif
 
+ifdef HAVE_DEV_TTY
+	BASIC_CFLAGS += -DHAVE_DEV_TTY
+endif
+
 ifdef DIR_HAS_BSD_GROUP_SEMANTICS
 	COMPAT_CFLAGS += -DDIR_HAS_BSD_GROUP_SEMANTICS
 endif
diff --git a/cache.h b/cache.h
index 270dfdb8a..10afd71d4 100644
--- a/cache.h
+++ b/cache.h
@@ -1028,7 +1028,6 @@ struct ref {
 extern struct ref *find_ref_by_name(const struct ref *list, const char *name);
 
 #define CONNECT_VERBOSE       (1u << 0)
-extern char *git_getpass(const char *prompt);
 extern struct child_process *git_connect(int fd[2], const char *url, const char *prog, int flags);
 extern int finish_connect(struct child_process *conn);
 extern int git_connection_is_socket(struct child_process *conn);
diff --git a/compat/terminal.c b/compat/terminal.c
new file mode 100644
index 000000000..6d16c8fba
--- /dev/null
+++ b/compat/terminal.c
@@ -0,0 +1,81 @@
+#include "git-compat-util.h"
+#include "compat/terminal.h"
+#include "sigchain.h"
+#include "strbuf.h"
+
+#ifdef HAVE_DEV_TTY
+
+static int term_fd = -1;
+static struct termios old_term;
+
+static void restore_term(void)
+{
+	if (term_fd < 0)
+		return;
+
+	tcsetattr(term_fd, TCSAFLUSH, &old_term);
+	term_fd = -1;
+}
+
+static void restore_term_on_signal(int sig)
+{
+	restore_term();
+	sigchain_pop(sig);
+	raise(sig);
+}
+
+char *git_terminal_prompt(const char *prompt, int echo)
+{
+	static struct strbuf buf = STRBUF_INIT;
+	int r;
+	FILE *fh;
+
+	fh = fopen("/dev/tty", "w+");
+	if (!fh)
+		return NULL;
+
+	if (!echo) {
+		struct termios t;
+
+		if (tcgetattr(fileno(fh), &t) < 0) {
+			fclose(fh);
+			return NULL;
+		}
+
+		old_term = t;
+		term_fd = fileno(fh);
+		sigchain_push_common(restore_term_on_signal);
+
+		t.c_lflag &= ~ECHO;
+		if (tcsetattr(fileno(fh), TCSAFLUSH, &t) < 0) {
+			term_fd = -1;
+			fclose(fh);
+			return NULL;
+		}
+	}
+
+	fputs(prompt, fh);
+	fflush(fh);
+
+	r = strbuf_getline(&buf, fh, '\n');
+	if (!echo) {
+		putc('\n', fh);
+		fflush(fh);
+	}
+
+	restore_term();
+	fclose(fh);
+
+	if (r == EOF)
+		return NULL;
+	return buf.buf;
+}
+
+#else
+
+char *git_terminal_prompt(const char *prompt, int echo)
+{
+	return getpass(prompt);
+}
+
+#endif
diff --git a/compat/terminal.h b/compat/terminal.h
new file mode 100644
index 000000000..97db7cd69
--- /dev/null
+++ b/compat/terminal.h
@@ -0,0 +1,6 @@
+#ifndef COMPAT_TERMINAL_H
+#define COMPAT_TERMINAL_H
+
+char *git_terminal_prompt(const char *prompt, int echo);
+
+#endif /* COMPAT_TERMINAL_H */
diff --git a/connect.c b/connect.c
index c8d0ea5d7..2ea5c3c0f 100644
--- a/connect.c
+++ b/connect.c
@@ -608,47 +608,3 @@ int finish_connect(struct child_process *conn)
 	free(conn);
 	return code;
 }
-
-char *git_getpass(const char *prompt)
-{
-	const char *askpass;
-	struct child_process pass;
-	const char *args[3];
-	static struct strbuf buffer = STRBUF_INIT;
-
-	askpass = getenv("GIT_ASKPASS");
-	if (!askpass)
-		askpass = askpass_program;
-	if (!askpass)
-		askpass = getenv("SSH_ASKPASS");
-	if (!askpass || !(*askpass)) {
-		char *result = getpass(prompt);
-		if (!result)
-			die_errno("Could not read password");
-		return result;
-	}
-
-	args[0] = askpass;
-	args[1]	= prompt;
-	args[2] = NULL;
-
-	memset(&pass, 0, sizeof(pass));
-	pass.argv = args;
-	pass.out = -1;
-
-	if (start_command(&pass))
-		exit(1);
-
-	strbuf_reset(&buffer);
-	if (strbuf_read(&buffer, pass.out, 20) < 0)
-		die("failed to read password from %s\n", askpass);
-
-	close(pass.out);
-
-	if (finish_command(&pass))
-		exit(1);
-
-	strbuf_setlen(&buffer, strcspn(buffer.buf, "\r\n"));
-
-	return buffer.buf;
-}
diff --git a/contrib/credential/osxkeychain/.gitignore b/contrib/credential/osxkeychain/.gitignore
new file mode 100644
index 000000000..6c5b7026c
--- /dev/null
+++ b/contrib/credential/osxkeychain/.gitignore
@@ -0,0 +1 @@
+git-credential-osxkeychain
diff --git a/contrib/credential/osxkeychain/Makefile b/contrib/credential/osxkeychain/Makefile
new file mode 100644
index 000000000..75c07f8be
--- /dev/null
+++ b/contrib/credential/osxkeychain/Makefile
@@ -0,0 +1,14 @@
+all:: git-credential-osxkeychain
+
+CC = gcc
+RM = rm -f
+CFLAGS = -g -Wall
+
+git-credential-osxkeychain: git-credential-osxkeychain.o
+	$(CC) -o $@ $< -Wl,-framework -Wl,Security
+
+git-credential-osxkeychain.o: git-credential-osxkeychain.c
+	$(CC) -c $(CFLAGS) $<
+
+clean:
+	$(RM) git-credential-osxkeychain git-credential-osxkeychain.o
diff --git a/contrib/credential/osxkeychain/git-credential-osxkeychain.c b/contrib/credential/osxkeychain/git-credential-osxkeychain.c
new file mode 100644
index 000000000..6beed123a
--- /dev/null
+++ b/contrib/credential/osxkeychain/git-credential-osxkeychain.c
@@ -0,0 +1,173 @@
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <Security/Security.h>
+
+static SecProtocolType protocol;
+static char *host;
+static char *path;
+static char *username;
+static char *password;
+static UInt16 port;
+
+static void die(const char *err, ...)
+{
+	char msg[4096];
+	va_list params;
+	va_start(params, err);
+	vsnprintf(msg, sizeof(msg), err, params);
+	fprintf(stderr, "%s\n", msg);
+	va_end(params);
+	exit(1);
+}
+
+static void *xstrdup(const char *s1)
+{
+	void *ret = strdup(s1);
+	if (!ret)
+		die("Out of memory");
+	return ret;
+}
+
+#define KEYCHAIN_ITEM(x) (x ? strlen(x) : 0), x
+#define KEYCHAIN_ARGS \
+	NULL, /* default keychain */ \
+	KEYCHAIN_ITEM(host), \
+	0, NULL, /* account domain */ \
+	KEYCHAIN_ITEM(username), \
+	KEYCHAIN_ITEM(path), \
+	port, \
+	protocol, \
+	kSecAuthenticationTypeDefault
+
+static void write_item(const char *what, const char *buf, int len)
+{
+	printf("%s=", what);
+	fwrite(buf, 1, len, stdout);
+	putchar('\n');
+}
+
+static void find_username_in_item(SecKeychainItemRef item)
+{
+	SecKeychainAttributeList list;
+	SecKeychainAttribute attr;
+
+	list.count = 1;
+	list.attr = &attr;
+	attr.tag = kSecAccountItemAttr;
+
+	if (SecKeychainItemCopyContent(item, NULL, &list, NULL, NULL))
+		return;
+
+	write_item("username", attr.data, attr.length);
+	SecKeychainItemFreeContent(&list, NULL);
+}
+
+static void find_internet_password(void)
+{
+	void *buf;
+	UInt32 len;
+	SecKeychainItemRef item;
+
+	if (SecKeychainFindInternetPassword(KEYCHAIN_ARGS, &len, &buf, &item))
+		return;
+
+	write_item("password", buf, len);
+	if (!username)
+		find_username_in_item(item);
+
+	SecKeychainItemFreeContent(NULL, buf);
+}
+
+static void delete_internet_password(void)
+{
+	SecKeychainItemRef item;
+
+	/*
+	 * Require at least a protocol and host for removal, which is what git
+	 * will give us; if you want to do something more fancy, use the
+	 * Keychain manager.
+	 */
+	if (!protocol || !host)
+		return;
+
+	if (SecKeychainFindInternetPassword(KEYCHAIN_ARGS, 0, NULL, &item))
+		return;
+
+	SecKeychainItemDelete(item);
+}
+
+static void add_internet_password(void)
+{
+	/* Only store complete credentials */
+	if (!protocol || !host || !username || !password)
+		return;
+
+	if (SecKeychainAddInternetPassword(
+	      KEYCHAIN_ARGS,
+	      KEYCHAIN_ITEM(password),
+	      NULL))
+		return;
+}
+
+static void read_credential(void)
+{
+	char buf[1024];
+
+	while (fgets(buf, sizeof(buf), stdin)) {
+		char *v;
+
+		if (!strcmp(buf, "\n"))
+			break;
+		buf[strlen(buf)-1] = '\0';
+
+		v = strchr(buf, '=');
+		if (!v)
+			die("bad input: %s", buf);
+		*v++ = '\0';
+
+		if (!strcmp(buf, "protocol")) {
+			if (!strcmp(v, "https"))
+				protocol = kSecProtocolTypeHTTPS;
+			else if (!strcmp(v, "http"))
+				protocol = kSecProtocolTypeHTTP;
+			else /* we don't yet handle other protocols */
+				exit(0);
+		}
+		else if (!strcmp(buf, "host")) {
+			char *colon = strchr(v, ':');
+			if (colon) {
+				*colon++ = '\0';
+				port = atoi(colon);
+			}
+			host = xstrdup(v);
+		}
+		else if (!strcmp(buf, "path"))
+			path = xstrdup(v);
+		else if (!strcmp(buf, "username"))
+			username = xstrdup(v);
+		else if (!strcmp(buf, "password"))
+			password = xstrdup(v);
+	}
+}
+
+int main(int argc, const char **argv)
+{
+	const char *usage =
+		"Usage: git credential-osxkeychain <get|store|erase>";
+
+	if (!argv[1])
+		die(usage);
+
+	read_credential();
+
+	if (!strcmp(argv[1], "get"))
+		find_internet_password();
+	else if (!strcmp(argv[1], "store"))
+		add_internet_password();
+	else if (!strcmp(argv[1], "erase"))
+		delete_internet_password();
+	/* otherwise, ignore unknown action */
+
+	return 0;
+}
diff --git a/credential.c b/credential.c
index a17eafea5..62d1c5681 100644
--- a/credential.c
+++ b/credential.c
@@ -3,6 +3,7 @@
 #include "string-list.h"
 #include "run-command.h"
 #include "url.h"
+#include "prompt.h"
 
 void credential_init(struct credential *c)
 {
@@ -108,7 +109,8 @@ static void credential_describe(struct credential *c, struct strbuf *out)
 		strbuf_addf(out, "/%s", c->path);
 }
 
-static char *credential_ask_one(const char *what, struct credential *c)
+static char *credential_ask_one(const char *what, struct credential *c,
+				int flags)
 {
 	struct strbuf desc = STRBUF_INIT;
 	struct strbuf prompt = STRBUF_INIT;
@@ -120,11 +122,7 @@ static char *credential_ask_one(const char *what, struct credential *c)
 	else
 		strbuf_addf(&prompt, "%s: ", what);
 
-	/* FIXME: for usernames, we should do something less magical that
-	 * actually echoes the characters. However, we need to read from
-	 * /dev/tty and not stdio, which is not portable (but getpass will do
-	 * it for us). http.c uses the same workaround. */
-	r = git_getpass(prompt.buf);
+	r = git_prompt(prompt.buf, flags);
 
 	strbuf_release(&desc);
 	strbuf_release(&prompt);
@@ -134,9 +132,11 @@ static char *credential_ask_one(const char *what, struct credential *c)
 static void credential_getpass(struct credential *c)
 {
 	if (!c->username)
-		c->username = credential_ask_one("Username", c);
+		c->username = credential_ask_one("Username", c,
+						 PROMPT_ASKPASS|PROMPT_ECHO);
 	if (!c->password)
-		c->password = credential_ask_one("Password", c);
+		c->password = credential_ask_one("Password", c,
+						 PROMPT_ASKPASS);
 }
 
 int credential_read(struct credential *c, FILE *fp)
diff --git a/imap-send.c b/imap-send.c
index 91763d301..e40125a22 100644
--- a/imap-send.c
+++ b/imap-send.c
@@ -25,6 +25,7 @@
 #include "cache.h"
 #include "exec_cmd.h"
 #include "run-command.h"
+#include "prompt.h"
 #ifdef NO_OPENSSL
 typedef void *SSL;
 #else
@@ -1208,13 +1209,10 @@ static struct store *imap_open_store(struct imap_server_conf *srvc)
 			goto bail;
 		}
 		if (!srvc->pass) {
-			char prompt[80];
-			sprintf(prompt, "Password (%s@%s): ", srvc->user, srvc->host);
-			arg = git_getpass(prompt);
-			if (!arg) {
-				perror("getpass");
-				exit(1);
-			}
+			struct strbuf prompt = STRBUF_INIT;
+			strbuf_addf(&prompt, "Password (%s@%s): ", srvc->user, srvc->host);
+			arg = git_getpass(prompt.buf);
+			strbuf_release(&prompt);
 			if (!*arg) {
 				fprintf(stderr, "Skipping account %s@%s, no password\n", srvc->user, srvc->host);
 				goto bail;
diff --git a/prompt.c b/prompt.c
new file mode 100644
index 000000000..72ab9de2f
--- /dev/null
+++ b/prompt.c
@@ -0,0 +1,63 @@
+#include "cache.h"
+#include "run-command.h"
+#include "strbuf.h"
+#include "prompt.h"
+#include "compat/terminal.h"
+
+static char *do_askpass(const char *cmd, const char *prompt)
+{
+	struct child_process pass;
+	const char *args[3];
+	static struct strbuf buffer = STRBUF_INIT;
+
+	args[0] = cmd;
+	args[1]	= prompt;
+	args[2] = NULL;
+
+	memset(&pass, 0, sizeof(pass));
+	pass.argv = args;
+	pass.out = -1;
+
+	if (start_command(&pass))
+		exit(1);
+
+	strbuf_reset(&buffer);
+	if (strbuf_read(&buffer, pass.out, 20) < 0)
+		die("failed to get '%s' from %s\n", prompt, cmd);
+
+	close(pass.out);
+
+	if (finish_command(&pass))
+		exit(1);
+
+	strbuf_setlen(&buffer, strcspn(buffer.buf, "\r\n"));
+
+	return buffer.buf;
+}
+
+char *git_prompt(const char *prompt, int flags)
+{
+	char *r;
+
+	if (flags & PROMPT_ASKPASS) {
+		const char *askpass;
+
+		askpass = getenv("GIT_ASKPASS");
+		if (!askpass)
+			askpass = askpass_program;
+		if (!askpass)
+			askpass = getenv("SSH_ASKPASS");
+		if (askpass && *askpass)
+			return do_askpass(askpass, prompt);
+	}
+
+	r = git_terminal_prompt(prompt, flags & PROMPT_ECHO);
+	if (!r)
+		die_errno("could not read '%s'", prompt);
+	return r;
+}
+
+char *git_getpass(const char *prompt)
+{
+	return git_prompt(prompt, PROMPT_ASKPASS);
+}
diff --git a/prompt.h b/prompt.h
new file mode 100644
index 000000000..04f321a78
--- /dev/null
+++ b/prompt.h
@@ -0,0 +1,10 @@
+#ifndef PROMPT_H
+#define PROMPT_H
+
+#define PROMPT_ASKPASS (1<<0)
+#define PROMPT_ECHO    (1<<1)
+
+char *git_prompt(const char *prompt, int flags);
+char *git_getpass(const char *prompt);
+
+#endif /* PROMPT_H */