Add SIGINFO (and for portability to SIGINFO-lacking systems, SIGUSR1)

handling to bsdtar.  When writing archives (including copying via the
@archive directive) a line is output to stderr indicating what is being
done (adding or copying), the path, and how far through the file we are;
extracting currently does not report progress within each file, but
this is likely to happen eventually.

Discussed with:	kientzle
Obtained from:	tarsnap

usr.bin/tar/Makefile

@@ -2,7 +2,7 @@
 
 PROG=	bsdtar
 BSDTAR_VERSION_STRING=2.5.0b
-SRCS=	bsdtar.c getdate.y matching.c read.c tree.c util.c write.c
+SRCS=	bsdtar.c getdate.y matching.c read.c siginfo.c tree.c util.c write.c
 WARNS?=	5
 DPADD=	${LIBARCHIVE} ${LIBBZ2} ${LIBZ}
 LDADD=	-larchive -lbz2 -lz

usr.bin/tar/bsdtar.h

@@ -96,6 +96,7 @@ struct bsdtar {
 	struct matching		*matching;	/* for matching.c */
 	struct security		*security;	/* for read.c */
 	struct name_cache	*uname_cache;	/* for write.c */
+	struct siginfo		*siginfo;	/* for siginfo.c */
 };
 
 void	bsdtar_errc(struct bsdtar *, int _eval, int _code,
@@ -114,6 +115,11 @@ int	process_lines(struct bsdtar *bsdtar, const char *pathname,
 	    int (*process)(struct bsdtar *, const char *));
 void	safe_fprintf(FILE *, const char *fmt, ...);
 void	set_chdir(struct bsdtar *, const char *newdir);
+void	siginfo_init(struct bsdtar *);
+void	siginfo_setinfo(struct bsdtar *, const char * oper,
+	    const char * path, int64_t size);
+void	siginfo_printinfo(struct bsdtar *, off_t progress);
+void	siginfo_done(struct bsdtar *);
 void	tar_mode_c(struct bsdtar *bsdtar);
 void	tar_mode_r(struct bsdtar *bsdtar);
 void	tar_mode_t(struct bsdtar *bsdtar);

usr.bin/tar/read.c

@@ -82,7 +82,21 @@ tar_mode_t(struct bsdtar *bsdtar)
 void
 tar_mode_x(struct bsdtar *bsdtar)
 {
+	/* We want to catch SIGINFO and SIGUSR1. */
+	siginfo_init(bsdtar);
+
 	read_archive(bsdtar, 'x');
+
+	/* Restore old SIGINFO + SIGUSR1 handlers. */
+	siginfo_done(bsdtar);
+}
+
+static void
+progress_func(void * cookie)
+{
+	struct bsdtar * bsdtar = cookie;
+
+	siginfo_printinfo(bsdtar, 0);
 }
 
 /*
@@ -119,6 +133,12 @@ read_archive(struct bsdtar *bsdtar, char mode)
 
 	do_chdir(bsdtar);
 
+	if (mode == 'x') {
+		/* Set an extract callback so that we can handle SIGINFO. */
+		archive_read_extract_set_progress_callback(a, progress_func,
+		    bsdtar);
+	}
+
 	if (mode == 'x' && bsdtar->option_chroot) {
 #if HAVE_CHROOT
 		if (chroot(".") != 0)
@@ -238,6 +258,12 @@ read_archive(struct bsdtar *bsdtar, char mode)
 				    archive_entry_pathname(entry));
 				fflush(stderr);
 			}
+
+			/* Tell the SIGINFO-handler code what we're doing. */
+			siginfo_setinfo(bsdtar, "extracting",
+			    archive_entry_pathname(entry), 0);
+			siginfo_printinfo(bsdtar, 0);
+
 			if (bsdtar->option_stdout)
 				r = archive_read_data_into_fd(a, 1);
 			else

usr.bin/tar/siginfo.c

@@ -0,0 +1,147 @@
+/*-
+ * Copyright 2008 Colin Percival
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "bsdtar_platform.h"
+__FBSDID("$FreeBSD$");
+
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "bsdtar.h"
+
+/* Is there a pending SIGINFO or SIGUSR1? */
+static volatile sig_atomic_t siginfo_received = 0;
+
+struct siginfo {
+	/* What sort of operation are we doing? */
+	char * oper;
+
+	/* What path are we handling? */
+	char * path;
+
+	/* How large is the archive entry? */
+	int64_t size;
+
+	/* Old signal handlers. */
+#ifdef SIGINFO
+	void (*siginfo_old)(int);
+#endif
+	void (*sigusr1_old)(int);
+};
+
+static void		 siginfo_handler(int sig);
+
+/* Handler for SIGINFO / SIGUSR1. */
+static void
+siginfo_handler(int sig)
+{
+
+	(void)sig; /* UNUSED */
+
+	/* Record that SIGINFO or SIGUSR1 has been received. */
+	siginfo_received = 1;
+}
+
+void
+siginfo_init(struct bsdtar *bsdtar)
+{
+
+	/* Allocate space for internal structure. */
+	if ((bsdtar->siginfo = malloc(sizeof(struct siginfo))) == NULL)
+		bsdtar_errc(bsdtar, 1, errno, "malloc failed");
+
+	/* Set the strings to NULL so that free() is safe. */
+	bsdtar->siginfo->path = bsdtar->siginfo->oper = NULL;
+
+#ifdef SIGINFO
+	/* We want to catch SIGINFO, if it exists. */
+	bsdtar->siginfo->siginfo_old = signal(SIGINFO, siginfo_handler);
+#endif
+	/* ... and treat SIGUSR1 the same way as SIGINFO. */
+	bsdtar->siginfo->sigusr1_old = signal(SIGUSR1, siginfo_handler);
+}
+
+void
+siginfo_setinfo(struct bsdtar *bsdtar, const char * oper, const char * path,
+    int64_t size)
+{
+
+	/* Free old operation and path strings. */
+	free(bsdtar->siginfo->oper);
+	free(bsdtar->siginfo->path);
+
+	/* Duplicate strings and store entry size. */
+	if ((bsdtar->siginfo->oper = strdup(oper)) == NULL)
+		bsdtar_errc(bsdtar, 1, errno, "Cannot strdup");
+	if ((bsdtar->siginfo->path = strdup(path)) == NULL)
+		bsdtar_errc(bsdtar, 1, errno, "Cannot strdup");
+	bsdtar->siginfo->size = size;
+}
+
+void
+siginfo_printinfo(struct bsdtar *bsdtar, off_t progress)
+{
+
+	/* If there's a signal to handle and we know what we're doing... */
+	if ((siginfo_received == 1) &&
+	    (bsdtar->siginfo->path != NULL) &&
+	    (bsdtar->siginfo->oper != NULL)) {
+		if (bsdtar->verbose)
+			fprintf(stderr, "\n");
+		if (bsdtar->siginfo->size > 0) {
+			safe_fprintf(stderr, "%s %s (%ju / %" PRId64 ")",
+			    bsdtar->siginfo->oper, bsdtar->siginfo->path,
+			    (uintmax_t)progress, bsdtar->siginfo->size);
+		} else {
+			safe_fprintf(stderr, "%s %s",
+			    bsdtar->siginfo->oper, bsdtar->siginfo->path);
+		}
+		if (!bsdtar->verbose)
+			fprintf(stderr, "\n");
+		siginfo_received = 0;
+	}
+}
+
+void
+siginfo_done(struct bsdtar *bsdtar)
+{
+
+#ifdef SIGINFO
+	/* Restore old SIGINFO handler. */
+	signal(SIGINFO, bsdtar->siginfo->siginfo_old);
+#endif
+	/* And the old SIGUSR1 handler, too. */
+	signal(SIGUSR1, bsdtar->siginfo->sigusr1_old);
+
+	/* Free strings. */
+	free(bsdtar->siginfo->path);
+	free(bsdtar->siginfo->oper);
+
+	/* Free internal data structure. */
+	free(bsdtar->siginfo);
+}

usr.bin/tar/write.c

@@ -174,6 +174,9 @@ tar_mode_c(struct bsdtar *bsdtar)
 	if (*bsdtar->argv == NULL && bsdtar->names_from_file == NULL)
 		bsdtar_errc(bsdtar, 1, 0, "no files or directories specified");
 
+	/* We want to catch SIGINFO and SIGUSR1. */
+	siginfo_init(bsdtar);
+
 	a = archive_write_new();
 
 	/* Support any format that the library supports. */
@@ -242,6 +245,9 @@ tar_mode_c(struct bsdtar *bsdtar)
 	}
 
 	archive_write_finish(a);
+
+	/* Restore old SIGINFO + SIGUSR1 handlers. */
+	siginfo_done(bsdtar);
 }
 
 /*
@@ -574,6 +580,10 @@ append_archive(struct bsdtar *bsdtar, struct archive *a, struct archive *ina)
 		if (bsdtar->verbose)
 			safe_fprintf(stderr, "a %s",
 			    archive_entry_pathname(in_entry));
+		siginfo_setinfo(bsdtar, "copying",
+		    archive_entry_pathname(in_entry),
+		    archive_entry_size(in_entry));
+		siginfo_printinfo(bsdtar, 0);
 
 		e = archive_write_header(a, in_entry);
 		if (e != ARCHIVE_OK) {
@@ -606,14 +616,18 @@ copy_file_data(struct bsdtar *bsdtar, struct archive *a, struct archive *ina)
 	char	buff[64*1024];
 	ssize_t	bytes_read;
 	ssize_t	bytes_written;
+	off_t	progress = 0;
 
 	bytes_read = archive_read_data(ina, buff, sizeof(buff));
 	while (bytes_read > 0) {
+		siginfo_printinfo(bsdtar, progress);
+
 		bytes_written = archive_write_data(a, buff, bytes_read);
 		if (bytes_written < bytes_read) {
 			bsdtar_warnc(bsdtar, 0, "%s", archive_error_string(a));
 			return (-1);
 		}
+		progress += bytes_written;
 		bytes_read = archive_read_data(ina, buff, sizeof(buff));
 	}
 
@@ -881,6 +895,13 @@ write_entry(struct bsdtar *bsdtar, struct archive *a, const struct stat *st,
 	if (!S_ISREG(st->st_mode))
 		archive_entry_set_size(entry, 0);
 
+	/* Record what we're doing, for the benefit of SIGINFO / SIGUSR1. */
+	siginfo_setinfo(bsdtar, "adding", archive_entry_pathname(entry),
+	    archive_entry_size(entry));
+
+	/* Handle SIGINFO / SIGUSR1 request if one was made. */
+	siginfo_printinfo(bsdtar, 0);
+
 	e = archive_write_header(a, entry);
 	if (e != ARCHIVE_OK) {
 		if (!bsdtar->verbose)
@@ -923,12 +944,15 @@ write_file_data(struct bsdtar *bsdtar, struct archive *a, int fd)
 	char	buff[64*1024];
 	ssize_t	bytes_read;
 	ssize_t	bytes_written;
+	off_t	progress = 0;
 
 	/* XXX TODO: Allocate buffer on heap and store pointer to
 	 * it in bsdtar structure; arrange cleanup as well. XXX */
 
 	bytes_read = read(fd, buff, sizeof(buff));
 	while (bytes_read > 0) {
+		siginfo_printinfo(bsdtar, progress);
+
 		bytes_written = archive_write_data(a, buff, bytes_read);
 		if (bytes_written < 0) {
 			/* Write failed; this is bad */
@@ -941,6 +965,7 @@ write_file_data(struct bsdtar *bsdtar, struct archive *a, int fd)
 			    "Truncated write; file may have grown while being archived.");
 			return (0);
 		}
+		progress += bytes_written;
 		bytes_read = read(fd, buff, sizeof(buff));
 	}
 	return 0;