bftw: Switch from taking separate parameters to a parameters struct

3 files changed, 50 insertions, 30 deletions

diff --git a/bftw.c b/bftw.c
index 118a441..6795bd0 100644
--- a/bftw.c
+++ b/bftw.c
@@ -764,11 +764,11 @@ static int bftw_stat(struct BFTW *ftwbuf, struct bfs_stat *sb) {
  */
 struct bftw_state {
 	/** bftw() callback. */
-	bftw_fn *fn;
-	/** bftw() flags. */
-	int flags;
+	bftw_callback *callback;
 	/** bftw() callback data. */
 	void *ptr;
+	/** bftw() flags. */
+	enum bftw_flags flags;
 
 	/** The appropriate errno value, if any. */
 	int error;
@@ -795,21 +795,21 @@ struct bftw_state {
 /**
  * Initialize the bftw() state.
  */
-static int bftw_state_init(struct bftw_state *state, const char *root, bftw_fn *fn, int nopenfd, int flags, void *ptr) {
+static int bftw_state_init(struct bftw_state *state, const char *root, const struct bftw_args *args) {
 	state->root = root;
-	state->fn = fn;
-	state->flags = flags;
-	state->ptr = ptr;
+	state->callback = args->callback;
+	state->ptr = args->ptr;
+	state->flags = args->flags;
 
 	state->error = 0;
 
-	if (nopenfd < 2) {
+	if (args->nopenfd < 2) {
 		errno = EMFILE;
 		goto err;
 	}
 
 	// -1 to account for dup()
-	if (bftw_cache_init(&state->cache, nopenfd - 1) != 0) {
+	if (bftw_cache_init(&state->cache, args->nopenfd - 1) != 0) {
 		goto err;
 	}
 
@@ -972,7 +972,7 @@ static enum bftw_action bftw_visit_path(struct bftw_state *state) {
 	// Defensive copy
 	struct BFTW ftwbuf = state->ftwbuf;
 
-	enum bftw_action action = state->fn(&ftwbuf, state->ptr);
+	enum bftw_action action = state->callback(&ftwbuf, state->ptr);
 	switch (action) {
 	case BFTW_CONTINUE:
 	case BFTW_SKIP_SIBLINGS:
@@ -1113,9 +1113,9 @@ static int bftw_state_destroy(struct bftw_state *state) {
 	}
 }
 
-int bftw(const char *path, bftw_fn *fn, int nopenfd, enum bftw_flags flags, void *ptr) {
+int bftw(const char *path, const struct bftw_args *args) {
 	struct bftw_state state;
-	if (bftw_state_init(&state, path, fn, nopenfd, flags, ptr) != 0) {
+	if (bftw_state_init(&state, path, args) != 0) {
 		return -1;
 	}
 
@@ -1163,7 +1163,7 @@ int bftw(const char *path, bftw_fn *fn, int nopenfd, enum bftw_flags flags, void
 
 			if (state.ftwbuf.typeflag == BFTW_DIR) {
 				const struct bfs_stat *statbuf = state.ftwbuf.statbuf;
-				if ((flags & BFTW_XDEV)
+				if ((args->flags & BFTW_XDEV)
 				    && statbuf
 				    && statbuf->dev != reader->dir->dev) {
 					goto read;
diff --git a/bftw.h b/bftw.h
index bed5800..6d1850f 100644
--- a/bftw.h
+++ b/bftw.h
@@ -1,6 +1,6 @@
 /****************************************************************************
  * bfs                                                                      *
- * Copyright (C) 2015-2018 Tavian Barnes <tavianator@tavianator.com>        *
+ * Copyright (C) 2015-2019 Tavian Barnes <tavianator@tavianator.com>        *
  *                                                                          *
  * Permission to use, copy, modify, and/or distribute this software for any *
  * purpose with or without fee is hereby granted.                           *
@@ -125,7 +125,7 @@ enum bftw_action {
  * @return
  *         An action value.
  */
-typedef enum bftw_action bftw_fn(struct BFTW *ftwbuf, void *ptr);
+typedef enum bftw_action bftw_callback(struct BFTW *ftwbuf, void *ptr);
 
 /**
  * Flags that control bftw() behavior.
@@ -148,6 +148,20 @@ enum bftw_flags {
 };
 
 /**
+ * Structure for holding the arguments passed to bftw().
+ */
+struct bftw_args {
+	/** The callback to invoke. */
+	bftw_callback *callback;
+	/** A pointer which is passed to the callback. */
+	void *ptr;
+	/** The maximum number of file descriptors to keep open. */
+	int nopenfd;
+	/** Flags that control bftw() behaviour. */
+	enum bftw_flags flags;
+};
+
+/**
  * Breadth First Tree Walk (or Better File Tree Walk).
  *
  * Like ftw(3) and nftw(3), this function walks a directory tree recursively,
@@ -156,17 +170,11 @@ enum bftw_flags {
  *
  * @param path
  *         The starting path.
- * @param fn
- *         The callback to invoke.
- * @param nopenfd
- *         The maximum number of file descriptors to keep open.
- * @param flags
- *         Flags that control bftw() behavior.
- * @param ptr
- *         A generic pointer which is passed to fn().
+ * @param args
+ *         The arguments that control the walk.
  * @return
  *         0 on success, or -1 on failure.
  */
-int bftw(const char *path, bftw_fn *fn, int nopenfd, enum bftw_flags flags, void *ptr);
+int bftw(const char *path, const struct bftw_args *args);
 
 #endif // BFS_BFTW_H
diff --git a/eval.c b/eval.c
index 53eacf8..028b31d 100644
--- a/eval.c
+++ b/eval.c
@@ -1383,8 +1383,6 @@ int eval_cmdline(const struct cmdline *cmdline) {
 		return EXIT_SUCCESS;
 	}
 
-	int nopenfd = infer_fdlimit(cmdline);
-
 	struct callback_args args = {
 		.cmdline = cmdline,
 		.ret = EXIT_SUCCESS,
@@ -1397,14 +1395,28 @@ int eval_cmdline(const struct cmdline *cmdline) {
 		args.seen = &seen;
 	}
 
+	struct bftw_args bftw_args = {
+		.callback = cmdline_callback,
+		.ptr = &args,
+		.nopenfd = infer_fdlimit(cmdline),
+		.flags = cmdline->flags,
+	};
+
 	for (struct root *root = cmdline->roots; root && !args.quit; root = root->next) {
 		if (cmdline->debug & DEBUG_SEARCH) {
-			fprintf(stderr, "bftw(\"%s\", cmdline_callback, %d, ", root->path, nopenfd);
-			dump_bftw_flags(cmdline->flags);
-			fprintf(stderr, ", &args)\n");
+			fprintf(stderr,
+				"bftw(\"%s\", { "
+				".callback = cmdline_callback, "
+				".ptr = &args, "
+				".nopenfd = %d, "
+				".flags = ",
+				root->path,
+				bftw_args.nopenfd);
+			dump_bftw_flags(bftw_args.flags);
+			fprintf(stderr, " })\n");
 		}
 
-		if (bftw(root->path, cmdline_callback, nopenfd, cmdline->flags, &args) != 0) {
+		if (bftw(root->path, &bftw_args) != 0) {
 			args.ret = EXIT_FAILURE;
 			perror("bftw()");
 		}