Check for free space before compression/decompression and abort if -f option is not enabled.

main.c

@@ -255,7 +255,8 @@ static void decompress_file(void)
 {
 	char *tmp, *tmpoutfile, *infilecopy = NULL;
 	int fd_in, fd_out = -1, fd_hist = -1;
-	i64 expected_size;
+	i64 expected_size, free_space;
+	struct statvfs fbuf;
 
 	if (!STDIN) {
 		if ((tmp = strrchr(control.infile, '.')) && strcmp(tmp,control.suffix)) {
@@ -320,6 +321,18 @@ static void decompress_file(void)
 		}
 	}
 
+	/* Check if there's enough free space on the device chosen to fit the
+	 * decompressed file. */
+	if (unlikely(fstatvfs(fd_in, &fbuf)))
+		fatal("Failed to fstatvfs in decompress_file\n");
+	free_space = fbuf.f_bsize * fbuf.f_bavail;
+	if (free_space < expected_size) {
+		if (FORCE_REPLACE)
+			print_err("Warning, inadequate free space detected, but attempting to decompress due to -f option being used.\n");
+		else
+			failure("Inadequate free space to decompress file, use -f to override.\n");
+	}
+
 	if (!(TEST_ONLY | STDOUT)) {
 		if (FORCE_REPLACE)
 			fd_out = open(control.outfile, O_WRONLY | O_CREAT | O_TRUNC, 0666);

rzip.c

@@ -740,6 +740,8 @@ void rzip_fd(int fd_in, int fd_out)
 		     elapsed_minutes, elapsed_seconds;
 	double finish_time, elapsed_time, chunkmbs;
 	char md5_resblock[MD5_DIGEST_SIZE];
+	struct statvfs fbuf;
+	i64 free_space;
 
 	md5_init_ctx (&control.ctx);
 
@@ -761,6 +763,19 @@ void rzip_fd(int fd_in, int fd_out)
 	} else
 		control.st_size = 0;
 
+	/* Check if there's enough free space on the device chosen to fit the
+	 * compressed file, based on the compressed file being as large as the
+	 * uncompressed file. */
+	if (unlikely(fstatvfs(fd_in, &fbuf)))
+		fatal("Failed to fstatvfs in decompress_file\n");
+	free_space = fbuf.f_bsize * fbuf.f_bavail;
+	if (free_space < control.st_size) {
+		if (FORCE_REPLACE)
+			print_err("Warning, possibly inadequate free space detected, but attempting to compress due to -f option being used.\n");
+		else
+			failure("Possibly inadequate free space to compress file, use -f to override.\n");
+	}
+
 	/* Optimal use of ram involves using no more than 2/3 of it, so we
 	 * allocate 1/3 of it to the main buffer and use a sliding mmap
 	 * buffer to work on 2/3 ram size, leaving enough ram for the

rzip.h

@@ -38,6 +38,7 @@
 #include <bzlib.h>
 #include <zlib.h>
 #include <pthread.h>
+#include <sys/statvfs.h>
 #include <sys/resource.h>
 #include <netinet/in.h>