Automatically create state/prefix directories

It'd be handy for the WR build system if new state directories could
be created as needed.  It is made so.  And to answer the first
question everyone, including me, has on reading this:  You can't
do system("mkdir -p ...") because the invoked shell would need to
run under pseudo, so it'd have to check for a server, and...

2 files changed, 51 insertions, 2 deletions

diff --git a/ChangeLog.txt b/ChangeLog.txt
index f82711d..8974d75 100644
--- a/ChangeLog.txt
+++ b/ChangeLog.txt
@@ -1,3 +1,6 @@
+2011-01-14:
+	* (seebs) Automatically create prefix/state directories.
+ 
 2011-01-13:
 	* (seebs) Subtle cache fixup.
 
diff --git a/pseudo_client.c b/pseudo_client.c
index 0dd2d9b..e96cd31 100644
--- a/pseudo_client.c
+++ b/pseudo_client.c
@@ -78,6 +78,28 @@ gid_t pseudo_egid;
 gid_t pseudo_sgid;
 gid_t pseudo_fgid;
 
+/* helper function to make a directory, just like mkdir -p.
+ * Can't use system() because the child shell would end up trying
+ * to do the same thing...
+ */
+static void
+mkdir_p(char *path) {
+	size_t len = strlen(path);
+	size_t i;
+
+	for (i = 1; i < len; ++i) {
+		/* try to create all the directories in path, ignoring
+		 * failures
+		 */
+		if (path[i] == '/') {
+			path[i] = '\0';
+			(void) mkdir(path, 0755);
+			path[i] = '/';
+		}
+	}
+	(void) mkdir(path, 0755);
+}
+
 void
 pseudo_init_client(void) {
 	char *env;
@@ -153,6 +175,12 @@ pseudo_init_client(void) {
 		if (pseudo_prefix_dir_fd == -1) {
 			if (pseudo_path) {
 				pseudo_prefix_dir_fd = open(pseudo_path, O_RDONLY);
+				/* directory is missing? */
+				if (pseudo_prefix_dir_fd == -1 && errno == ENOENT) {
+					pseudo_debug(1, "prefix directory doesn't exist, trying to create\n");
+					mkdir_p(pseudo_path);
+					pseudo_prefix_dir_fd = open(pseudo_path, O_RDONLY);
+				}
 				pseudo_prefix_dir_fd = pseudo_fd(pseudo_prefix_dir_fd, MOVE_FD);
 			} else {
 				pseudo_diag("No prefix available to to find server.\n");
@@ -170,13 +198,19 @@ pseudo_init_client(void) {
 		if (pseudo_localstate_dir_fd == -1) {
 			if (pseudo_path) {
 				pseudo_localstate_dir_fd = open(pseudo_path, O_RDONLY);
+				/* directory is missing? */
+				if (pseudo_localstate_dir_fd == -1 && errno == ENOENT) {
+					pseudo_debug(1, "local state directory doesn't exist, trying to create\n");
+					mkdir_p(pseudo_path);
+					pseudo_localstate_dir_fd = open(pseudo_path, O_RDONLY);
+				}
 				pseudo_localstate_dir_fd = pseudo_fd(pseudo_localstate_dir_fd, MOVE_FD);
 			} else {
 				pseudo_diag("No prefix available to to find server.\n");
 				exit(1);
 			}
 			if (pseudo_localstate_dir_fd == -1) {
-				pseudo_diag("Can't open prefix path (%s) for server: %s\n",
+				pseudo_diag("Can't open local state path (%s) for server: %s\n",
 					pseudo_path,
 					strerror(errno));
 				exit(1);
@@ -806,6 +840,12 @@ pseudo_client_shutdown(void) {
 	if (pseudo_prefix_dir_fd == -1) {
 		if (pseudo_path) {
 			pseudo_prefix_dir_fd = open(pseudo_path, O_RDONLY);
+			/* directory is missing? */
+			if (pseudo_prefix_dir_fd == -1 && errno == ENOENT) {
+				pseudo_debug(1, "prefix directory doesn't exist, trying to create\n");
+				mkdir_p(pseudo_path);
+				pseudo_prefix_dir_fd = open(pseudo_path, O_RDONLY);
+			}
 			pseudo_prefix_dir_fd = pseudo_fd(pseudo_prefix_dir_fd, COPY_FD);
 			free(pseudo_path);
 		} else {
@@ -823,6 +863,12 @@ pseudo_client_shutdown(void) {
 	if (pseudo_localstate_dir_fd == -1) {
 		if (pseudo_path) {
 			pseudo_localstate_dir_fd = open(pseudo_path, O_RDONLY);
+			/* directory is missing? */
+			if (pseudo_localstate_dir_fd == -1 && errno == ENOENT) {
+				pseudo_debug(1, "local state dir doesn't exist, trying to create\n");
+				mkdir_p(pseudo_path);
+				pseudo_localstate_dir_fd = open(pseudo_path, O_RDONLY);
+			}
 			pseudo_localstate_dir_fd = pseudo_fd(pseudo_localstate_dir_fd, COPY_FD);
 			free(pseudo_path);
 		} else {
@@ -830,7 +876,7 @@ pseudo_client_shutdown(void) {
 			exit(1);
 		}
 		if (pseudo_localstate_dir_fd == -1) {
-			pseudo_diag("Can't open prefix path (%s) for server. (%s)\n",
+			pseudo_diag("Can't open local state path (%s) for server. (%s)\n",
 				pseudo_localstatedir_path(NULL),
 				strerror(errno));
 			exit(1);