[PATCH] erofs-utils: support randomizing algorithms in debugging mode

[Gao Xiang]

It's used for multiple algorithms selftest.

Signed-off-by: Gao Xiang <hsiangkao at linux.alibaba.com>
---
 include/erofs/config.h |  1 +
 lib/compress.c         | 11 +++++++++++
 mkfs/main.c            |  5 +++++
 3 files changed, 17 insertions(+)

diff --git a/include/erofs/config.h b/include/erofs/config.h
index 17db98c..7b64d89 100644
--- a/include/erofs/config.h
+++ b/include/erofs/config.h
@@ -41,6 +41,7 @@ struct erofs_configure {
 	bool c_legacy_compress;
 #ifndef NDEBUG
 	bool c_random_pclusterblks;
+	bool c_random_algorithms;
 #endif
 	char c_timeinherit;
 	char c_chunkbits;
diff --git a/lib/compress.c b/lib/compress.c
index 012a90c..4c314e7 100644
--- a/lib/compress.c
+++ b/lib/compress.c
@@ -860,6 +860,16 @@ int erofs_write_compressed_file(struct erofs_inode *inode, int fd)
 	if (cfg.c_fragments && !cfg.c_dedupe)
 		inode->z_advise |= Z_EROFS_ADVISE_INTERLACED_PCLUSTER;
 
+#ifndef NDEBUG
+	if (cfg.c_random_algorithms) {
+		while (1) {
+			inode->z_algorithmtype[0] =
+				rand() % EROFS_MAX_COMPR_CFG;
+			if (erofs_ccfg[inode->z_algorithmtype[0]].enable)
+				break;
+		}
+	}
+#endif
 	ctx.ccfg = &erofs_ccfg[inode->z_algorithmtype[0]];
 	inode->z_algorithmtype[0] = ctx.ccfg[0].algorithmtype;
 	inode->z_algorithmtype[1] = 0;
@@ -1075,6 +1085,7 @@ int z_erofs_compress_init(struct erofs_buffer_head *sb_bh)
 		if (ret < 0)
 			return ret;
 		erofs_ccfg[i].algorithmtype = ret;
+		erofs_ccfg[i].enable = true;
 		sbi.available_compr_algs |= 1 << ret;
 		if (ret != Z_EROFS_COMPRESSION_LZ4)
 			erofs_sb_set_compr_cfgs();
diff --git a/mkfs/main.c b/mkfs/main.c
index bb3628f..206a669 100644
--- a/mkfs/main.c
+++ b/mkfs/main.c
@@ -45,6 +45,7 @@ static struct option long_options[] = {
 	{"all-root", no_argument, NULL, 7},
 #ifndef NDEBUG
 	{"random-pclusterblks", no_argument, NULL, 8},
+	{"random-algorithms", no_argument, NULL, 18},
 #endif
 	{"max-extent-bytes", required_argument, NULL, 9},
 	{"compress-hints", required_argument, NULL, 10},
@@ -111,6 +112,7 @@ static void usage(void)
 	      " --quiet               quiet execution (do not write anything to standard output.)\n"
 #ifndef NDEBUG
 	      " --random-pclusterblks randomize pclusterblks for big pcluster (debugging only)\n"
+	      " --random-algorithms   randomize per-file algorithms (debugging only)\n"
 #endif
 	      " --mount-point=X       X=prefix of target fs path (default: /)\n"
 #ifdef WITH_ANDROID
@@ -370,6 +372,9 @@ static int mkfs_parse_options_cfg(int argc, char *argv[])
 		case 8:
 			cfg.c_random_pclusterblks = true;
 			break;
+		case 18:
+			cfg.c_random_algorithms = true;
+			break;
 #endif
 		case 9:
 			cfg.c_max_decompressed_extent_bytes =
-- 
2.36.1