eval: Use 512-byte blocks for -ls when POSIXLY_CORRECT is set

This matches the behaviour of GNU find, and allows bfs to match the
output of BSD find as well.  Fixes #77.

4 files changed, 10 insertions, 4 deletions

diff --git a/ctx.c b/ctx.c
index b17d148..5c9c9bf 100644
--- a/ctx.c
+++ b/ctx.c
@@ -1,6 +1,6 @@
 /****************************************************************************
  * bfs                                                                      *
- * Copyright (C) 2015-2020 Tavian Barnes <tavianator@tavianator.com>        *
+ * Copyright (C) 2015-2021 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.                           *
@@ -72,6 +72,7 @@ struct bfs_ctx *bfs_ctx_new(void) {
 	ctx->optlevel = 3;
 	ctx->debug = 0;
 	ctx->ignore_races = false;
+	ctx->posixly_correct = false;
 	ctx->status = false;
 	ctx->unique = false;
 	ctx->warn = false;
diff --git a/ctx.h b/ctx.h
index 7af4060..f089b84 100644
--- a/ctx.h
+++ b/ctx.h
@@ -1,6 +1,6 @@
 /****************************************************************************
  * bfs                                                                      *
- * Copyright (C) 2015-2020 Tavian Barnes <tavianator@tavianator.com>        *
+ * Copyright (C) 2015-2021 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.                           *
@@ -82,6 +82,8 @@ struct bfs_ctx {
 	enum debug_flags debug;
 	/** Whether to ignore deletions that race with bfs (-ignore_readdir_race). */
 	bool ignore_races;
+	/** Whether to follow POSIXisms more closely ($POSIXLY_CORRECT). */
+	bool posixly_correct;
 	/** Whether to show a status bar (-status). */
 	bool status;
 	/** Whether to only return unique files (-unique). */
diff --git a/eval.c b/eval.c
index 51b621b..55cd812 100644
--- a/eval.c
+++ b/eval.c
@@ -644,7 +644,8 @@ bool eval_fls(const struct expr *expr, struct eval_state *state) {
 	}
 
 	uintmax_t ino = statbuf->ino;
-	uintmax_t blocks = ((uintmax_t)statbuf->blocks*BFS_STAT_BLKSIZE + 1023)/1024;
+	uintmax_t block_size = state->ctx->posixly_correct ? 512 : 1024;
+	uintmax_t blocks = ((uintmax_t)statbuf->blocks*BFS_STAT_BLKSIZE + block_size - 1)/block_size;
 	char mode[11];
 	xstrmode(statbuf->mode, mode);
 	char acl = bfs_check_acl(ftwbuf) > 0 ? '+' : ' ';
diff --git a/parse.c b/parse.c
index 8f34c08..1129ebd 100644
--- a/parse.c
+++ b/parse.c
@@ -3614,7 +3614,9 @@ struct bfs_ctx *bfs_parse_cmdline(int argc, char *argv[]) {
 	bool stdout_tty = isatty(STDOUT_FILENO);
 	bool stderr_tty = isatty(STDERR_FILENO);
 
-	if (!getenv("POSIXLY_CORRECT")) {
+	if (getenv("POSIXLY_CORRECT")) {
+		ctx->posixly_correct = true;
+	} else {
 		ctx->warn = stdin_tty;
 	}