Adding upstream version 1.47.0.upstream/1.47.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 213 insertions, 0 deletions

diff --git a/lib/blkid/save.c b/lib/blkid/save.c
new file mode 100644
index 0000000..6f4499c
--- /dev/null
+++ b/lib/blkid/save.c
@@ -0,0 +1,213 @@
+/*
+ * save.c - write the cache struct to disk
+ *
+ * Copyright (C) 2001 by Andreas Dilger
+ * Copyright (C) 2003 Theodore Ts'o
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the
+ * GNU Lesser General Public License.
+ * %End-Header%
+ */
+
+#include "config.h"
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/types.h>
+#ifdef HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+#ifdef HAVE_SYS_MKDEV_H
+#include <sys/mkdev.h>
+#endif
+#ifdef HAVE_ERRNO_H
+#include <errno.h>
+#endif
+#include "blkidP.h"
+
+#ifdef _WIN32
+#include "windows.h"
+#endif
+
+static int save_dev(blkid_dev dev, FILE *file)
+{
+	struct list_head *p;
+
+	if (!dev || dev->bid_name[0] != '/')
+		return 0;
+
+	DBG(DEBUG_SAVE,
+	    printf("device %s, type %s\n", dev->bid_name, dev->bid_type ?
+		   dev->bid_type : "(null)"));
+
+	fprintf(file,
+		"<device DEVNO=\"0x%04lx\" TIME=\"%ld\"",
+		(unsigned long) dev->bid_devno, (long) dev->bid_time);
+	if (dev->bid_pri)
+		fprintf(file, " PRI=\"%d\"", dev->bid_pri);
+	list_for_each(p, &dev->bid_tags) {
+		blkid_tag tag = list_entry(p, struct blkid_struct_tag, bit_tags);
+		fprintf(file, " %s=\"%s\"", tag->bit_name,tag->bit_val);
+	}
+	fprintf(file, ">%s</device>\n", dev->bid_name);
+
+	return 0;
+}
+
+/*
+ * Write out the cache struct to the cache file on disk.
+ */
+int blkid_flush_cache(blkid_cache cache)
+{
+	struct list_head *p;
+	char *tmp = NULL;
+	const char *opened = NULL;
+	const char *filename;
+	FILE *file = NULL;
+	int fd, ret = 0;
+	struct stat st;
+
+	if (!cache)
+		return -BLKID_ERR_PARAM;
+
+	if (list_empty(&cache->bic_devs) ||
+	    !(cache->bic_flags & BLKID_BIC_FL_CHANGED)) {
+		DBG(DEBUG_SAVE, printf("skipping cache file write\n"));
+		return 0;
+	}
+
+	filename = cache->bic_filename ? cache->bic_filename: BLKID_CACHE_FILE;
+
+	/* If we can't write to the cache file, then don't even try */
+	if (((ret = stat(filename, &st)) < 0 && errno != ENOENT) ||
+	    (ret == 0 && access(filename, W_OK) < 0)) {
+		DBG(DEBUG_SAVE,
+		    printf("can't write to cache file %s\n", filename));
+		return 0;
+	}
+
+	/*
+	 * Try and create a temporary file in the same directory so
+	 * that in case of error we don't overwrite the cache file.
+	 * If the cache file doesn't yet exist, it isn't a regular
+	 * file (e.g. /dev/null or a socket), or we couldn't create
+	 * a temporary file then we open it directly.
+	 */
+	if (ret == 0 && S_ISREG(st.st_mode)) {
+		tmp = malloc(strlen(filename) + 8);
+		if (tmp) {
+			mode_t save_umask = umask(022);
+			sprintf(tmp, "%s-XXXXXX", filename);
+			fd = mkstemp(tmp);
+			umask(save_umask);
+			if (fd >= 0) {
+				file = fdopen(fd, "w");
+				opened = tmp;
+			}
+#ifndef _WIN32
+			fchmod(fd, 0644);
+#else
+			chmod(tmp, 0644);
+#endif
+		}
+	}
+
+	if (!file) {
+		file = fopen(filename, "w");
+		opened = filename;
+	}
+
+	DBG(DEBUG_SAVE,
+	    printf("writing cache file %s (really %s)\n",
+		   filename, opened));
+
+	if (!file) {
+		ret = errno;
+		goto errout;
+	}
+
+	list_for_each(p, &cache->bic_devs) {
+		blkid_dev dev = list_entry(p, struct blkid_struct_dev, bid_devs);
+		if (!dev->bid_type)
+			continue;
+		if ((ret = save_dev(dev, file)) < 0)
+			break;
+	}
+
+	if (ret >= 0) {
+		cache->bic_flags &= ~BLKID_BIC_FL_CHANGED;
+		ret = 1;
+	}
+
+	fclose(file);
+	if (opened != filename) {
+		if (ret < 0) {
+			(void) unlink(opened);
+			DBG(DEBUG_SAVE,
+			    printf("unlinked temp cache %s\n", opened));
+		} else {
+			char *backup;
+
+			backup = malloc(strlen(filename) + 5);
+			if (backup) {
+				sprintf(backup, "%s.old", filename);
+				unlink(backup);
+#if defined(__GNUC__) && __GNUC__ >= 5
+/* explicit (void) cast is not enough with glibc and _FORTIFY_SOURCE */
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wunused-result"
+#endif
+				(void) link(filename, backup);
+#if defined(__GNUC__) && __GNUC__ >= 5
+#pragma GCC diagnostic pop
+#endif
+				free(backup);
+			}
+			if (rename(opened, filename) < 0)
+				(void) unlink(opened);
+			DBG(DEBUG_SAVE,
+			    printf("moved temp cache %s\n", opened));
+		}
+	}
+
+errout:
+	free(tmp);
+	return ret;
+}
+
+#ifdef TEST_PROGRAM
+int main(int argc, char **argv)
+{
+	blkid_cache cache = NULL;
+	int ret;
+
+	blkid_debug_mask = DEBUG_ALL;
+	if (argc > 2) {
+		fprintf(stderr, "Usage: %s [filename]\n"
+			"Test loading/saving a cache (filename)\n", argv[0]);
+		exit(1);
+	}
+
+	if ((ret = blkid_get_cache(&cache, "/dev/null")) != 0) {
+		fprintf(stderr, "%s: error creating cache (%d)\n",
+			argv[0], ret);
+		exit(1);
+	}
+	if ((ret = blkid_probe_all(cache)) < 0) {
+		fprintf(stderr, "error (%d) probing devices\n", ret);
+		exit(1);
+	}
+	cache->bic_filename = blkid_strdup(argv[1]);
+
+	if ((ret = blkid_flush_cache(cache)) < 0) {
+		fprintf(stderr, "error (%d) saving cache\n", ret);
+		exit(1);
+	}
+
+	blkid_put_cache(cache);
+
+	return ret;
+}
+#endif