install: Expect EINTR while copying

Both copy_file_range() and read() / write() in our fallback loop can be
interrupted before copying anything at all, in which case it returns -1
and sets errno to EINTR.  If that happens, we should retry, not fail.

While here, drop the size argument from copy() (we always want to copy
the entire file anyway) and add test cases which exercise the metalog
and digest functionality.

PR:		293028
MFC after:	1 week
Reviewed by:	kevans
Differential Revision:	https://reviews.freebsd.org/D55168

usr.bin/xinstall/tests/install_test.sh

@@ -512,6 +512,42 @@ set_optional_exec_body()
 	atf_check test ! -x testfile
 }
 
+atf_test_case metalog
+metalog_head() {
+	atf_set "descr" "Test metalog generation"
+}
+metalog_body() {
+	atf_check install -M metalog -D dst -m 0755 -d dst
+	echo ". type=dir mode=0755" >expect
+	atf_check install -M metalog -D dst -m 0705 -d dst/dir
+	echo "./dir type=dir mode=0705" >>expect
+	atf_check -o save:file echo "Hello, world!"
+	atf_check install -M metalog -D dst -m 0604 file dst/dir
+	echo "./dir/file type=file mode=0604 size=14" >>expect
+	atf_check install -M metalog -D dst -lrs dir/file dst/"li nk"
+	echo "./li\040nk type=link mode=0755 link=dir/file" >>expect
+	atf_check mtree -f expect -p dst
+	atf_check -o file:expect cat metalog
+}
+
+atf_test_case digest
+digest_head() {
+	atf_set "descr" "Compute digest while copying"
+}
+digest_body() {
+	atf_check mkdir src dst
+	atf_check -e ignore dd if=/dev/random of=src/file bs=1m count=1
+	for alg in md5 rmd160 sha1 sha256 sha512 ; do
+		rm -f dst/file digest metalog
+		atf_check -o save:digest $alg -q src/file
+		atf_check install -M metalog -D dst -h $alg -m 0644 src/file dst
+		echo -n "./file type=file mode=0644 size=1048576 $alg=" >expect
+		cat digest >>expect
+		atf_check cmp src/file dst/file
+		atf_check -o file:expect cat metalog
+	done
+}
+
 atf_init_test_cases() {
 	atf_add_test_case copy_to_empty
 	atf_add_test_case copy_to_nonexistent
@@ -557,4 +593,6 @@ atf_init_test_cases() {
 	atf_add_test_case set_owner_group_mode
 	atf_add_test_case set_owner_group_mode_unpriv
 	atf_add_test_case set_optional_exec
+	atf_add_test_case metalog
+	atf_add_test_case digest
 }

usr.bin/xinstall/xinstall.c

@@ -140,7 +140,7 @@ static char *destdir, *digest, *fflags, *metafile, *tags;
 
 static int	compare(int, const char *, size_t, int, const char *, size_t,
 		    char **);
-static char	*copy(int, const char *, int, const char *, off_t);
+static char	*copy(int, const char *, int, const char *);
 static int	create_tempfile(const char *, char *, size_t);
 static char	*quiet_mktemp(char *template);
 static char	*digest_file(const char *);
@@ -877,7 +877,7 @@ install(const char *from_name, const char *to_name, u_long fset, u_int flags)
 			}
 			if (!stripped) {
 				digestresult = copy(from_fd, from_name, to_fd,
-				    tempfile, from_sb.st_size);
+				    tempfile);
 			}
 		}
 	}
@@ -1175,8 +1175,7 @@ create_tempfile(const char *path, char *temp, size_t tsize)
  *	copy from one file to another
  */
 static char *
-copy(int from_fd, const char *from_name, int to_fd, const char *to_name,
-    off_t size)
+copy(int from_fd, const char *from_name, int to_fd, const char *to_name)
 {
 	static char *buf = NULL;
 	static size_t bufsize;
@@ -1198,8 +1197,8 @@ copy(int from_fd, const char *from_name, int to_fd, const char *to_name,
 	if (digesttype == DIGEST_NONE) {
 		do {
 			ret = copy_file_range(from_fd, NULL, to_fd, NULL,
-			    (size_t)size, 0);
-		} while (ret > 0);
+			    SSIZE_MAX, 0);
+		} while (ret > 0 || (ret < 0 && errno == EINTR));
 		if (ret == 0)
 			goto done;
 		if (errno != EINVAL) {
@@ -1227,29 +1226,30 @@ copy(int from_fd, const char *from_name, int to_fd, const char *to_name,
 		if (buf == NULL)
 			err(1, "Not enough memory");
 	}
-	while ((nr = read(from_fd, buf, bufsize)) > 0) {
-		if ((nw = write(to_fd, buf, nr)) != nr) {
-			serrno = errno;
-			(void)unlink(to_name);
-			if (nw >= 0) {
-				errx(EX_OSERR,
-				    "short write to %s: %jd bytes written, "
-				    "%jd bytes asked to write",
-				    to_name, (uintmax_t)nw,
-				    (uintmax_t)size);
-			} else {
-				errno = serrno;
-				err(EX_OSERR, "%s", to_name);
-			}
-		}
-		digest_update(&ctx, buf, nr);
-	}
-	if (nr != 0) {
+	for (;;) {
+		if ((nr = read(from_fd, buf, bufsize)) < 0) {
+			if (errno == EINTR)
+				continue;
 			serrno = errno;
 			(void)unlink(to_name);
 			errno = serrno;
 			err(EX_OSERR, "%s", from_name);
 		}
+		if (nr <= 0)
+			break;
+		digest_update(&ctx, buf, nr);
+		while (nr > 0) {
+			if ((nw = write(to_fd, buf, nr)) < 0) {
+				if (errno == EINTR)
+					continue;
+				serrno = errno;
+				(void)unlink(to_name);
+				errno = serrno;
+				err(EX_OSERR, "%s", to_name);
+			}
+			nr -= nw;
+		}
+	}
 #ifndef BOOTSTRAP_XINSTALL
 done:
 #endif