git: 8113cc827611 - main - cat: use copy_file_range(2) with fallback to previous behavior

[Martin Matuska]

The branch main has been updated by mm:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=8113cc827611a88540736c92ced7d3a7020a1723

commit 8113cc827611a88540736c92ced7d3a7020a1723
Author:     Martin Matuska <m...@freebsd.org>
AuthorDate: 2023-07-08 18:31:38 +0000
Commit:     Martin Matuska <m...@freebsd.org>
CommitDate: 2023-07-08 19:51:15 +0000

    cat: use copy_file_range(2) with fallback to previous behavior
    
    This allows to use special filesystem features like server-side
    copying on NFS 4.2 or block cloning on OpenZFS 2.2.
    
    Reviewed by:    imp, rmacklem
    Differential revision:  https://reviews.freebsd.org/D40882
---
 bin/cat/cat.c | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/bin/cat/cat.c b/bin/cat/cat.c
index a58bbe93835e..1158a839cfd8 100644
--- a/bin/cat/cat.c
+++ b/bin/cat/cat.c
@@ -83,6 +83,7 @@ static void usage(void) __dead2;
 static void scanfiles(char *argv[], int cooked);
 #ifndef BOOTSTRAP_CAT
 static void cook_cat(FILE *);
+static ssize_t in_kernel_copy(int);
 #endif
 static void raw_cat(int);
 
@@ -280,7 +281,16 @@ scanfiles(char *argv[], int cooked __unused)
                        }
 #endif
                } else {
+#ifndef BOOTSTRAP_CAT
+                       if (in_kernel_copy(fd) == -1) {
+                               if (errno == EINVAL)
+                                       raw_cat(fd);
+                               else
+                                       err(1, "stdout");
+                       }
+#else
                        raw_cat(fd);
+#endif
                        if (fd != STDIN_FILENO)
                                close(fd);
                }
@@ -380,6 +390,21 @@ ilseq:
        if (ferror(stdout))
                err(1, "stdout");
 }
+
+static ssize_t
+in_kernel_copy(int rfd)
+{
+       int wfd;
+       ssize_t ret;
+
+       wfd = fileno(stdout);
+       ret = 1;
+
+       while (ret > 0)
+               ret = copy_file_range(rfd, NULL, wfd, NULL, SSIZE_MAX, 0);
+
+       return (ret);
+}
 #endif /* BOOTSTRAP_CAT */
 
 static void