xspawn: API tweaks

3 files changed, 48 insertions, 43 deletions

diff --git a/src/exec.c b/src/exec.c
index 87250ac..3ff6f92 100644
--- a/src/exec.c
+++ b/src/exec.c
@@ -362,9 +362,7 @@ static int bfs_exec_spawn(const struct bfs_exec *execbuf) {
 		return -1;
 	}
 
-	if (bfs_spawn_setflags(&spawn, BFS_SPAWN_USE_PATH) != 0) {
-		goto fail;
-	}
+	spawn.flags |= BFS_SPAWN_USE_PATH;
 
 	if (execbuf->wd_fd >= 0) {
 		if (bfs_spawn_addfchdir(&spawn, execbuf->wd_fd) != 0) {
@@ -374,7 +372,7 @@ static int bfs_exec_spawn(const struct bfs_exec *execbuf) {
 
 	// Reset RLIMIT_NOFILE if necessary, to avoid breaking applications that use select()
 	if (rlim_cmp(ctx->orig_nofile.rlim_cur, ctx->cur_nofile.rlim_cur) < 0) {
-		if (bfs_spawn_addsetrlimit(&spawn, RLIMIT_NOFILE, &ctx->orig_nofile) != 0) {
+		if (bfs_spawn_setrlimit(&spawn, RLIMIT_NOFILE, &ctx->orig_nofile) != 0) {
 			goto fail;
 		}
 	}
diff --git a/src/xspawn.c b/src/xspawn.c
index 6a2ebba..3974768 100644
--- a/src/xspawn.c
+++ b/src/xspawn.c
@@ -47,14 +47,14 @@ int bfs_spawn_init(struct bfs_spawn *ctx) {
 	ctx->flags = BFS_SPAWN_USE_POSIX;
 	SLIST_INIT(ctx);
 
-	errno = posix_spawnattr_init(&ctx->attr);
+	errno = posix_spawn_file_actions_init(&ctx->actions);
 	if (errno != 0) {
 		return -1;
 	}
 
-	errno = posix_spawn_file_actions_init(&ctx->actions);
+	errno = posix_spawnattr_init(&ctx->attr);
 	if (errno != 0) {
-		posix_spawnattr_destroy(&ctx->attr);
+		posix_spawn_file_actions_destroy(&ctx->actions);
 		return -1;
 	}
 
@@ -62,8 +62,8 @@ int bfs_spawn_init(struct bfs_spawn *ctx) {
 }
 
 int bfs_spawn_destroy(struct bfs_spawn *ctx) {
-	posix_spawn_file_actions_destroy(&ctx->actions);
 	posix_spawnattr_destroy(&ctx->attr);
+	posix_spawn_file_actions_destroy(&ctx->actions);
 
 	for_slist (struct bfs_spawn_action, action, ctx) {
 		free(action);
@@ -72,8 +72,22 @@ int bfs_spawn_destroy(struct bfs_spawn *ctx) {
 	return 0;
 }
 
-int bfs_spawn_setflags(struct bfs_spawn *ctx, enum bfs_spawn_flags flags) {
-	ctx->flags |= flags;
+/** Set some posix_spawnattr flags. */
+static inline int bfs_spawn_addflags(struct bfs_spawn *ctx, short flags) {
+	short prev;
+	errno = posix_spawnattr_getflags(&ctx->attr, &prev);
+	if (errno != 0) {
+		return -1;
+	}
+
+	short next = prev | flags;
+	if (next != prev) {
+		errno = posix_spawnattr_setflags(&ctx->attr, next);
+		if (errno != 0) {
+			return -1;
+		}
+	}
+
 	return 0;
 }
 
@@ -150,13 +164,15 @@ int bfs_spawn_addfchdir(struct bfs_spawn *ctx, int fd) {
 #  endif
 #endif
 
-#if BFS_HAS_POSIX_SPAWN_FCHDIR || BFS_HAS_POSIX_SPAWN_FCHDIR_NP
+#if BFS_HAS_POSIX_SPAWN_FCHDIR
+#  define BFS_POSIX_SPAWN_FCHDIR posix_spawn_file_actions_addfchdir
+#elif BFS_HAS_POSIX_SPAWN_FCHDIR_NP
+#  define BFS_POSIX_SPAWN_FCHDIR posix_spawn_file_actions_addfchdir_np
+#endif
+
+#ifdef BFS_POSIX_SPAWN_FCHDIR
 	if (ctx->flags & BFS_SPAWN_USE_POSIX) {
-#  if BFS_HAS_POSIX_SPAWN_FCHDIR
-		errno = posix_spawn_file_actions_addfchdir(&ctx->actions, fd);
-#  else
-		errno = posix_spawn_file_actions_addfchdir_np(&ctx->actions, fd);
-#  endif
+		errno = BFS_POSIX_SPAWN_FCHDIR(&ctx->actions, fd);
 		if (errno != 0) {
 			free(action);
 			return -1;
@@ -171,22 +187,14 @@ int bfs_spawn_addfchdir(struct bfs_spawn *ctx, int fd) {
 	return 0;
 }
 
-int bfs_spawn_addsetrlimit(struct bfs_spawn *ctx, int resource, const struct rlimit *rl) {
+int bfs_spawn_setrlimit(struct bfs_spawn *ctx, int resource, const struct rlimit *rl) {
 	struct bfs_spawn_action *action = bfs_spawn_action(BFS_SPAWN_SETRLIMIT);
 	if (!action) {
 		goto fail;
 	}
 
 #ifdef POSIX_SPAWN_SETRLIMIT
-	short flags;
-	errno = posix_spawnattr_getflags(&ctx->attr, &flags);
-	if (errno != 0) {
-		goto fail;
-	}
-
-	flags |= POSIX_SPAWN_SETRLIMIT;
-	errno = posix_spawnattr_setflags(&ctx->attr, flags);
-	if (errno != 0) {
+	if (bfs_spawn_addflags(ctx, POSIX_SPAWN_SETRLIMIT) != 0) {
 		goto fail;
 	}
 
diff --git a/src/xspawn.h b/src/xspawn.h
index 2a3d736..e3ad1eb 100644
--- a/src/xspawn.h
+++ b/src/xspawn.h
@@ -34,59 +34,58 @@ struct bfs_spawn {
 	struct bfs_spawn_action *head;
 	struct bfs_spawn_action **tail;
 
-	/** pthread_spawn() context, for when we can use it. */
-	posix_spawnattr_t attr;
+	/** posix_spawn() context, for when we can use it. */
 	posix_spawn_file_actions_t actions;
+	posix_spawnattr_t attr;
 };
 
 /**
  * Create a new bfs_spawn() context.
  *
- * @return 0 on success, -1 on failure.
+ * @return
+ *         0 on success, -1 on failure.
  */
 int bfs_spawn_init(struct bfs_spawn *ctx);
 
 /**
  * Destroy a bfs_spawn() context.
  *
- * @return 0 on success, -1 on failure.
+ * @return
+ *         0 on success, -1 on failure.
  */
 int bfs_spawn_destroy(struct bfs_spawn *ctx);
 
 /**
- * Set the flags for a bfs_spawn() context.
- *
- * @return 0 on success, -1 on failure.
- */
-int bfs_spawn_setflags(struct bfs_spawn *ctx, enum bfs_spawn_flags flags);
-
-/**
  * Add a close() action to a bfs_spawn() context.
  *
- * @return 0 on success, -1 on failure.
+ * @return
+ *         0 on success, -1 on failure.
  */
 int bfs_spawn_addclose(struct bfs_spawn *ctx, int fd);
 
 /**
  * Add a dup2() action to a bfs_spawn() context.
  *
- * @return 0 on success, -1 on failure.
+ * @return
+ *         0 on success, -1 on failure.
  */
 int bfs_spawn_adddup2(struct bfs_spawn *ctx, int oldfd, int newfd);
 
 /**
  * Add an fchdir() action to a bfs_spawn() context.
  *
- * @return 0 on success, -1 on failure.
+ * @return
+ *         0 on success, -1 on failure.
  */
 int bfs_spawn_addfchdir(struct bfs_spawn *ctx, int fd);
 
 /**
- * Add a setrlimit() action to a bfs_spawn() context.
+ * Apply setrlimit() to a bfs_spawn() context.
  *
- * @return 0 on success, -1 on failure.
+ * @return
+ *         0 on success, -1 on failure.
  */
-int bfs_spawn_addsetrlimit(struct bfs_spawn *ctx, int resource, const struct rlimit *rl);
+int bfs_spawn_setrlimit(struct bfs_spawn *ctx, int resource, const struct rlimit *rl);
 
 /**
  * Spawn a new process.