File 0001-fs-fix-FIEMAP_MAX_OFFSET-type-silliness-in... of Package bees

Overview Repositories Revisions Requests Users Attributes Meta

File 0001-fs-fix-FIEMAP_MAX_OFFSET-type-silliness-in-fiemap.h.patch of Package bees (Revision bb01363c0738302b83735988bade9d1f)

Currently displaying revision bb01363c0738302b83735988bade9d1f , Show latest

From 12e80658a8cfb5dc1d8676e3696681ad32fab552 Mon Sep 17 00:00:00 2001
From: Zygo Blaxell <bees@furryterror.org>
Date: Wed, 6 Oct 2021 15:05:28 -0400
Subject: [PATCH] fs: fix FIEMAP_MAX_OFFSET type silliness in fiemap.h

In fiemap.h the members of struct fiemap are declared as __u64, but the
FIEMAP_MAX_OFFSET macro is an unsigned long long value:

$ grep FIEMAP_MAX_OFFSET -r /usr/include/
	/usr/include/linux/fiemap.h:#define FIEMAP_MAX_OFFSET   (~0ULL)
	$ grep fe_length -r /usr/include/
	/usr/include/linux/fiemap.h:    __u64 fe_length;   /* length in bytes for this extent */

This results in a type mismatch error on architectures like ppc64le:

fiemap.cc:31:35: note:   deduced conflicting types for parameter 'const _Tp' ('long unsigned int' and 'long long unsigned int')
	    31 |                 fm.fm_length = min(fm.fm_length, FIEMAP_MAX_OFFSET - fm.fm_start);
	       |                                ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Work around this by copying the macro into a uint64_t constant,
and not using the macro any more.

Fixes: https://github.com/Zygo/bees/issues/194

Signed-off-by: Zygo Blaxell <bees@furryterror.org>
---
 include/crucible/fs.h | 6 +++++-
 src/fiemap.cc         | 4 ++--
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/include/crucible/fs.h b/include/crucible/fs.h
index fcd61e055197..dae574015f8c 100644
--- a/include/crucible/fs.h
+++ b/include/crucible/fs.h
@@ -143,8 +143,12 @@ namespace crucible {
 
 	struct Fiemap : public fiemap {
 
+		// because fiemap.h insists on giving FIEMAP_MAX_OFFSET
+		// a different type from the struct fiemap members
+		static const uint64_t s_fiemap_max_offset = FIEMAP_MAX_OFFSET;
+
 		// Get entire file
-		Fiemap(uint64_t start = 0, uint64_t length = FIEMAP_MAX_OFFSET);
+		Fiemap(uint64_t start = 0, uint64_t length = s_fiemap_max_offset);
 
 		void do_ioctl(int fd);
 
diff --git a/src/fiemap.cc b/src/fiemap.cc
index 1618d3b04308..fb6085ac9738 100644
--- a/src/fiemap.cc
+++ b/src/fiemap.cc
@@ -28,13 +28,13 @@ main(int argc, char **argv)
 		if (argc > 2) { fm.fm_start = stoull(argv[2], nullptr, 0); }
 		if (argc > 3) { fm.fm_length = stoull(argv[3], nullptr, 0); }
 		if (argc > 4) { fm.fm_flags = stoull(argv[4], nullptr, 0); }
-		fm.fm_length = min(fm.fm_length, FIEMAP_MAX_OFFSET - fm.fm_start);
+		fm.fm_length = min(fm.fm_length, Fiemap::s_fiemap_max_offset - fm.fm_start);
 		uint64_t stop_at = fm.fm_start + fm.fm_length;
 		uint64_t last_byte = fm.fm_start;
 		do {
 			fm.do_ioctl(fd);
 			// cerr << fm;
-			uint64_t last_logical = FIEMAP_MAX_OFFSET;
+			uint64_t last_logical = Fiemap::s_fiemap_max_offset;
 			for (auto &extent : fm.m_extents) {
 				if (extent.fe_logical > last_byte) {
 					cout << "Log " << to_hex(last_byte) << ".." << to_hex(extent.fe_logical) << " Hole" << endl;
-- 
2.33.0

Places

File 0001-fs-fix-FIEMAP_MAX_OFFSET-type-silliness-in-fiemap.h.patch of Package bees (Revision bb01363c0738302b83735988bade9d1f)

Places