Adapted from Debian: https://sources.debian.org/patches/sqlite3/3.32.3-1/20-hurd-locking-style.patch
Upstream status: Not upstreamed.

This patch is needed to get offloading to work.

Sqlite can use simple file locking mode, but that does not work for the Hurd;
a second sqlite process fails with a "locking protocol" error.

See also: https://bugs.debian.org/529734.

diff -purN sqlite-autoconf-3310100/sqlite3.c sqlite-autoconf-3310100-/sqlite3.c
--- sqlite-autoconf-3310100/sqlite3.c	2020-01-27 21:25:19.000000000 +0100
+++ sqlite-autoconf-3310100-/sqlite3.c	2020-07-01 11:50:13.768333806 +0200
@@ -33189,7 +33189,7 @@ SQLITE_PRIVATE const char *sqlite3Opcode
 # include <sys/mman.h>
 #endif
 
-#if SQLITE_ENABLE_LOCKING_STYLE
+#if SQLITE_ENABLE_LOCKING_STYLE || defined(__GNU__)
 /* # include <sys/ioctl.h> */
 # include <sys/file.h>
 # include <sys/param.h>
@@ -35676,7 +35676,7 @@ static int dotlockClose(sqlite3_file *id
 **
 ** Omit this section if SQLITE_ENABLE_LOCKING_STYLE is turned off
 */
-#if SQLITE_ENABLE_LOCKING_STYLE
+#if SQLITE_ENABLE_LOCKING_STYLE || defined(__GNU__)
 
 /*
 ** Retry flock() calls that fail with EINTR
@@ -38586,7 +38586,7 @@ IOMETHODS(
   0                         /* xShmMap method */
 )
 
-#if SQLITE_ENABLE_LOCKING_STYLE
+#if SQLITE_ENABLE_LOCKING_STYLE || defined(__GNU__)
 IOMETHODS(
   flockIoFinder,            /* Finder function name */
   flockIoMethods,           /* sqlite3_io_methods object name */
@@ -41142,6 +41142,8 @@ SQLITE_API int sqlite3_os_init(void){
     UNIXVFS("unix",          autolockIoFinder ),
 #elif OS_VXWORKS
     UNIXVFS("unix",          vxworksIoFinder ),
+#elif defined(__GNU__)
+    UNIXVFS("unix",          flockIoFinder ),
 #else
     UNIXVFS("unix",          posixIoFinder ),
 #endif
@@ -41151,7 +41153,7 @@ SQLITE_API int sqlite3_os_init(void){
 #if OS_VXWORKS
     UNIXVFS("unix-namedsem", semIoFinder ),
 #endif
-#if SQLITE_ENABLE_LOCKING_STYLE || OS_VXWORKS
+#if SQLITE_ENABLE_LOCKING_STYLE || OS_VXWORKS || defined(__GNU__)
     UNIXVFS("unix-posix",    posixIoFinder ),
 #endif
 #if SQLITE_ENABLE_LOCKING_STYLE
19fe9d61f768cb5235921071f293d729413ebc5'>root</a>/<a href='/guix/log/gnu?id=519fe9d61f768cb5235921071f293d729413ebc5'>gnu</a>/<a href='/guix/log/gnu/packages?id=519fe9d61f768cb5235921071f293d729413ebc5'>packages</a>/<a href='/guix/log/gnu/packages/selinux.scm?id=519fe9d61f768cb5235921071f293d729413ebc5'>selinux.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/packages/selinux.scm?id=519fe9d61f768cb5235921071f293d729413ebc5&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2020-07-12 23:08:15 +0200'>2020-07-12</span></td><td><a href='/guix/commit/gnu/packages/selinux.scm?id=b0e7b6992f3f845e83cfbca4d700b51dba50b4d5'>gnu: Remove ".git" from "https://github/…/….git".</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-02-03 15:29:15 +0100'>2020-02-03</span></td><td><a href='/guix/commit/gnu/packages/selinux.scm?id=2401678f56695b80b5a46d2aef931afcde278c2c'>gnu: checkpolicy: Fix cross-compilation.</a><span class='msg-avail'>...</span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2020-02-03 15:29:15 +0100'>2020-02-03</span></td><td><a href='/guix/commit/gnu/packages/selinux.scm?id=7981c0be07d4e7723c263bedc5ef258d814a0ffb'>gnu: libsepol: Fix cross-compilation.</a><span class='msg-avail'>...</span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2019-12-05 17:59:10 +0100'>2019-12-05</span></td><td><a href='/guix/commit/gnu/packages/selinux.scm?id=9e837ea0f35bb232eebfc8603264459ba4ffa52f'>gnu: SELinux: Update to 3.0.</a><span class='msg-avail'>...</span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2019-07-11 15:40:20 +0200'>2019-07-11</span></td><td><a href='/guix/commit/gnu/packages/selinux.scm?id=568d060327291dd3fcb0e20c3b5c493047ae6902'>gnu: libselinux: Install python bindings to separate output.</a><span class='msg-avail'>...</span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2019-01-15 14:46:44 +0100'>2019-01-15</span></td><td><a href='/guix/commit/gnu/packages/selinux.scm?id=44d10b1f722856ab8e9b942804aa7ef33e2ef739'>gnu: Separate Python core packages from the rest.</a><span class='msg-avail'>...</span></td><td>Ricardo Wurmus</td></tr>