replace: copy_file_range()

BUG: https://bugzilla.samba.org/show_bug.cgi?id=12033

Signed-off-by: Ralph Boehme <slow@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>

3 files changed, 46 insertions, 1 deletions

diff --git a/lib/replace/replace.c b/lib/replace/replace.c
index 99b18e82590..0652cb4e6d6 100644
--- a/lib/replace/replace.c
+++ b/lib/replace/replace.c
@@ -1056,3 +1056,28 @@ const char *rep_getprogname(void)
 #endif /* HAVE_PROGRAM_INVOCATION_SHORT_NAME */
 }
 #endif /* HAVE_GETPROGNAME */
+
+#ifndef HAVE_COPY_FILE_RANGE
+# ifdef HAVE_SYSCALL_COPY_FILE_RANGE
+# include <sys/syscall.h>
+# endif
+ssize_t rep_copy_file_range(int fd_in,
+			    loff_t *off_in,
+			    int fd_out,
+			    loff_t *off_out,
+			    size_t len,
+			    unsigned int flags)
+{
+# ifdef HAVE_SYSCALL_COPY_FILE_RANGE
+	return syscall(__NR_copy_file_range,
+		       fd_in,
+		       off_in,
+		       fd_out,
+		       off_out,
+		       len,
+		       flags);
+# endif /* HAVE_SYSCALL_COPY_FILE_RANGE */
+	errno = ENOSYS;
+	return -1;
+}
+#endif /* HAVE_COPY_FILE_RANGE */
diff --git a/lib/replace/replace.h b/lib/replace/replace.h
index e08bf7c2e58..a546185d47a 100644
--- a/lib/replace/replace.h
+++ b/lib/replace/replace.h
@@ -964,6 +964,16 @@ int rep_memset_s(void *dest, size_t destsz, int ch, size_t count);
 const char *rep_getprogname(void);
 #endif
 
+#ifndef HAVE_COPY_FILE_RANGE
+#define copy_file_range rep_copy_file_range
+ssize_t rep_copy_file_range(int fd_in,
+			    loff_t *off_in,
+			    int fd_out,
+			    loff_t *off_out,
+			    size_t len,
+			    unsigned int flags);
+#endif /* HAVE_COPY_FILE_RANGE */
+
 #ifndef FALL_THROUGH
 # ifdef HAVE_FALLTHROUGH_ATTRIBUTE
 #  define FALL_THROUGH __attribute__ ((fallthrough))
diff --git a/lib/replace/wscript b/lib/replace/wscript
index 5d6324ef619..12f995f3198 100644
--- a/lib/replace/wscript
+++ b/lib/replace/wscript
@@ -454,6 +454,16 @@ def configure(conf):
     conf.CHECK_FUNCS('getpwent_r getpwnam_r getpwuid_r epoll_create')
     conf.CHECK_FUNCS('port_create')
     conf.CHECK_FUNCS('getprogname')
+    if not conf.CHECK_FUNCS('copy_file_range'):
+        conf.CHECK_CODE('''
+#include <sys/syscall.h>
+#include <unistd.h>
+syscall(SYS_copy_file_range,0,NULL,0,NULL,0,0);
+                        ''',
+                        'HAVE_SYSCALL_COPY_FILE_RANGE',
+                        msg='Checking whether we have copy_file_range system call')
+    if conf.CONFIG_SET('HAVE_COPY_FILE_RANGE') or conf.CONFIG_SET('HAVE_SYSCALL_COPY_FILE_RANGE'):
+        conf.DEFINE('USE_COPY_FILE_RANGE', 1)
 
     conf.SET_TARGET_TYPE('attr', 'EMPTY')
 
@@ -835,7 +845,7 @@ REPLACEMENT_FUNCTIONS = {
                   'strsep', 'strtok_r', 'strtoll', 'strtoull', 'setenv', 'unsetenv',
                   'utime', 'utimes', 'dup2', 'chown', 'link', 'readlink',
                   'symlink', 'lchown', 'realpath', 'memmem', 'vdprintf',
-                  'dprintf', 'get_current_dir_name',
+                  'dprintf', 'get_current_dir_name', 'copy_file_range',
                   'strerror_r', 'clock_gettime', 'memset_s'],
     'timegm.c': ['timegm'],
     # Note: C99_VSNPRINTF is not a function, but a special condition