git: 21a6c9bd6f2f - stable/12 - ar: Avoid overwriting the stdout file stream pointer

From: Ed Maste <emaste_at_FreeBSD.org>
Date: Wed, 09 Feb 2022 16:38:10 UTC
The branch stable/12 has been updated by emaste:

URL: https://cgit.FreeBSD.org/src/commit/?id=21a6c9bd6f2f962ce22e17b99e2c1d6afa15a5e3

commit 21a6c9bd6f2f962ce22e17b99e2c1d6afa15a5e3
Author:     Mark Johnston <markj@FreeBSD.org>
AuthorDate: 2022-01-27 22:10:17 +0000
Commit:     Ed Maste <emaste@FreeBSD.org>
CommitDate: 2022-02-09 15:28:20 +0000

    ar: Avoid overwriting the stdout file stream pointer
    
    This doesn't work with musl, which defines stdout as FILE * const.
    Instead, explicitly pass the desired output stream to ar_read_archive().
    
    No functional change intended.
    
    Reviewed by:    emaste
    MFC after:      1 week
    Sponsored by:   The FreeBSD Foundation
    Differential Revision:  https://reviews.freebsd.org/D34064
    
    (cherry picked from commit 41e6398f9bc1bba4ed872118e742096d692fdfec)
---
 usr.bin/ar/acpyacc.y | 14 ++++++--------
 usr.bin/ar/ar.c      |  2 +-
 usr.bin/ar/ar.h      |  2 +-
 usr.bin/ar/read.c    | 18 +++++++++---------
 4 files changed, 17 insertions(+), 19 deletions(-)

diff --git a/usr.bin/ar/acpyacc.y b/usr.bin/ar/acpyacc.y
index 34156e1d2d58..1ce7197ef222 100644
--- a/usr.bin/ar/acpyacc.y
+++ b/usr.bin/ar/acpyacc.y
@@ -406,7 +406,7 @@ arscp_extract(struct list *list)
 	if (!arscp_target_exist())
 		return;
 	arscp_mlist2argv(list);
-	ar_read_archive(bsdar, 'x');
+	ar_read_archive(bsdar, 'x', stdout);
 	arscp_free_argv();
 	arscp_free_mlist(list);
 }
@@ -422,7 +422,7 @@ arscp_list(void)
 	bsdar->argv = NULL;
 	/* Always verbose. */
 	bsdar->options |= AR_V;
-	ar_read_archive(bsdar, 't');
+	ar_read_archive(bsdar, 't', stdout);
 	bsdar->options &= ~AR_V;
 }
 
@@ -433,10 +433,9 @@ arscp_dir(char *archive, struct list *list, char *rlt)
 	FILE	*out;
 
 	/* If rlt != NULL, redirect output to it */
-	out = NULL;
+	out = stdout;
 	if (rlt) {
-		out = stdout;
-		if ((stdout = fopen(rlt, "w")) == NULL)
+		if ((out = fopen(rlt, "w")) == NULL)
 			bsdar_errc(bsdar, errno, "fopen %s failed", rlt);
 	}
 
@@ -449,13 +448,12 @@ arscp_dir(char *archive, struct list *list, char *rlt)
 	}
 	if (verbose)
 		bsdar->options |= AR_V;
-	ar_read_archive(bsdar, 't');
+	ar_read_archive(bsdar, 't', out);
 	bsdar->options &= ~AR_V;
 
 	if (rlt) {
-		if (fclose(stdout) == EOF)
+		if (fclose(out) == EOF)
 			bsdar_errc(bsdar, errno, "fclose %s failed", rlt);
-		stdout = out;
 		free(rlt);
 	}
 	free(archive);
diff --git a/usr.bin/ar/ar.c b/usr.bin/ar/ar.c
index 4353efcb0ff2..93887ebebcfb 100644
--- a/usr.bin/ar/ar.c
+++ b/usr.bin/ar/ar.c
@@ -331,7 +331,7 @@ main(int argc, char **argv)
 		exitcode = ar_write_archive(bsdar, bsdar->mode);
 		break;
 	case 'p': case 't': case 'x':
-		exitcode = ar_read_archive(bsdar, bsdar->mode);
+		exitcode = ar_read_archive(bsdar, bsdar->mode, stdout);
 		break;
 	default:
 		bsdar_usage();
diff --git a/usr.bin/ar/ar.h b/usr.bin/ar/ar.h
index bcccf93a6016..66a7888c3e1c 100644
--- a/usr.bin/ar/ar.h
+++ b/usr.bin/ar/ar.h
@@ -115,7 +115,7 @@ struct bsdar {
 };
 
 void	ar_mode_script(struct bsdar *ar);
-int	ar_read_archive(struct bsdar *ar, int mode);
+int	ar_read_archive(struct bsdar *ar, int mode, FILE *out);
 int	ar_write_archive(struct bsdar *ar, int mode);
 void	bsdar_errc(struct bsdar *, int _code, const char *fmt, ...) __dead2;
 void	bsdar_warnc(struct bsdar *, int _code, const char *fmt, ...);
diff --git a/usr.bin/ar/read.c b/usr.bin/ar/read.c
index 81e0bfce1b7e..84b94a1f4d77 100644
--- a/usr.bin/ar/read.c
+++ b/usr.bin/ar/read.c
@@ -47,7 +47,7 @@ __FBSDID("$FreeBSD$");
  * Handle read modes: 'x', 't' and 'p'.
  */
 int
-ar_read_archive(struct bsdar *bsdar, int mode)
+ar_read_archive(struct bsdar *bsdar, int mode, FILE *out)
 {
 	struct archive		 *a;
 	struct archive_entry	 *entry;
@@ -123,18 +123,18 @@ ar_read_archive(struct bsdar *bsdar, int mode)
 				size = archive_entry_size(entry);
 				mtime = archive_entry_mtime(entry);
 				(void)strmode(md, buf);
-				(void)fprintf(stdout, "%s %6d/%-6d %8ju ",
+				(void)fprintf(out, "%s %6d/%-6d %8ju ",
 				    buf + 1, uid, gid, (uintmax_t)size);
 				tp = localtime(&mtime);
 				(void)strftime(buf, sizeof(buf),
 				    "%b %e %H:%M %Y", tp);
-				(void)fprintf(stdout, "%s %s", buf, name);
+				(void)fprintf(out, "%s %s", buf, name);
 			} else
-				(void)fprintf(stdout, "%s", name);
+				(void)fprintf(out, "%s", name);
 			r = archive_read_data_skip(a);
 			if (r == ARCHIVE_WARN || r == ARCHIVE_RETRY ||
 			    r == ARCHIVE_FATAL) {
-				(void)fprintf(stdout, "\n");
+				(void)fprintf(out, "\n");
 				bsdar_warnc(bsdar, archive_errno(a), "%s",
 				    archive_error_string(a));
 			}
@@ -142,14 +142,14 @@ ar_read_archive(struct bsdar *bsdar, int mode)
 			if (r == ARCHIVE_FATAL)
 				break;
 
-			(void)fprintf(stdout, "\n");
+			(void)fprintf(out, "\n");
 		} else {
 			/* mode == 'x' || mode = 'p' */
 			if (mode == 'p') {
 				if (bsdar->options & AR_V) {
-					(void)fprintf(stdout, "\n<%s>\n\n",
+					(void)fprintf(out, "\n<%s>\n\n",
 					    name);
-					fflush(stdout);
+					fflush(out);
 				}
 				r = archive_read_data_into_fd(a, 1);
 			} else {
@@ -172,7 +172,7 @@ ar_read_archive(struct bsdar *bsdar, int mode)
 				}
 
 				if (bsdar->options & AR_V)
-					(void)fprintf(stdout, "x - %s\n", name);
+					(void)fprintf(out, "x - %s\n", name);
 				/* Disallow absolute paths. */
 				if (name[0] == '/') {
 					bsdar_warnc(bsdar, 0,