Alter how tmux handles the working directory to internally use file descriptors

rather than strings.

- Each session still has a current working directory.

- New sessions still get their working directory from the client that created
  them or its attached session if any.

- New windows are created by default in the session working directory.

- The -c flag to new, neww, splitw allows the working directory to be
  overridden.

- The -c flag to attach let's the session working directory be changed.

- The default-path option has been removed.

To get the equivalent to default-path '.', do:

        bind c neww -c $PWD

To get the equivalent of default-path '', do:

        bind c neww -c '#{pane_current_path}'

The equivalent of default-path '~' is left as an exercise for the reader.

This also changes the client identify protocol to be a set of messages rather
than one as well as some other changes that should make it easier to make
backwards-compatible protocol changes in future.

1 files changed, 25 insertions, 29 deletions

diff --git a/cmd-save-buffer.c b/cmd-save-buffer.c
index c6c54019..3788fc22 100644
--- a/cmd-save-buffer.c
+++ b/cmd-save-buffer.c
@@ -20,8 +20,10 @@
 #include <sys/stat.h>
 
 #include <errno.h>
+#include <fcntl.h>
 #include <stdlib.h>
 #include <string.h>
+#include <unistd.h>
 
 #include "tmux.h"
 
@@ -53,17 +55,14 @@ enum cmd_retval
 cmd_save_buffer_exec(struct cmd *self, struct cmd_q *cmdq)
 {
 	struct args		*args = self->args;
-	struct client		*c;
+	struct client		*c = cmdq->client;
 	struct session          *s;
 	struct paste_buffer	*pb;
-	const char		*path, *newpath, *wd;
-	char			*cause, *start, *end;
-	size_t			 size, used;
-	int			 buffer;
-	mode_t			 mask;
+	const char		*path;
+	char			*cause, *start, *end, *msg;
+	size_t			 size, used, msglen;
+	int			 cwd, fd, buffer;
 	FILE			*f;
-	char			*msg;
-	size_t			 msglen;
 
 	if (!args_has(args, 'b')) {
 		if ((pb = paste_get_top(&global_buffers)) == NULL) {
@@ -90,7 +89,6 @@ cmd_save_buffer_exec(struct cmd *self, struct cmd_q *cmdq)
 	else
 		path = args->argv[0];
 	if (strcmp(path, "-") == 0) {
-		c = cmdq->client;
 		if (c == NULL) {
 			cmdq_error(cmdq, "can't write to stdout");
 			return (CMD_RETURN_ERROR);
@@ -100,28 +98,26 @@ cmd_save_buffer_exec(struct cmd *self, struct cmd_q *cmdq)
 		goto do_print;
 	}
 
-	c = cmdq->client;
-	if (c != NULL)
-		wd = c->cwd;
-	else if ((s = cmd_current_session(cmdq, 0)) != NULL) {
-		wd = options_get_string(&s->options, "default-path");
-		if (*wd == '\0')
-			wd = s->cwd;
-	} else
-		wd = NULL;
-	if (wd != NULL && *wd != '\0') {
-		newpath = get_full_path(wd, path);
-		if (newpath != NULL)
-			path = newpath;
-	}
-
-	mask = umask(S_IRWXG | S_IRWXO);
-	if (args_has(self->args, 'a'))
-		f = fopen(path, "ab");
+	if (c != NULL && c->session == NULL)
+		cwd = c->cwd;
+	else if ((s = cmd_current_session(cmdq, 0)) != NULL)
+		cwd = s->cwd;
 	else
-		f = fopen(path, "wb");
-	umask(mask);
+		cwd = AT_FDCWD;
+
+	f = NULL;
+	if (args_has(self->args, 'a')) {
+		fd = openat(cwd, path, O_CREAT|O_RDWR|O_APPEND, 0600);
+		if (fd != -1)
+			f = fdopen(fd, "ab");
+	} else {
+		fd = openat(cwd, path, O_CREAT|O_RDWR, 0600);
+		if (fd != -1)
+			f = fdopen(fd, "wb");
+	}
 	if (f == NULL) {
+		if (fd != -1)
+			close(fd);
 		cmdq_error(cmdq, "%s: %s", path, strerror(errno));
 		return (CMD_RETURN_ERROR);
 	}