Re: Re: [PATCH v2] erofs-utils: introduce exclude dirs and files

[Li GuiFu via Linux-erofs <linux-erofs@lists.ozlabs.org>]

Hi
My e-mail of foxmail was broken in the mainline, use aliyun instead.

On 2020/2/5 1:02, Gao Xiang via Linux-erofs wrote:
> Hi Guifu,
> 
> I cleanup the whole patch and get rid of all dedupe check in order
> to make it as simple as possible since I think not too many exclude
> files in general.
> 
> Please take some time helping testing the following patch and
> hope to get your feedback.
> 
> Thanks,
> Gao Xiang
> 
> 
> 
>>From 600fc166cdaaa0e458181729245ce11affa83ac5 Mon Sep 17 00:00:00 2001
> From: Li Guifu <blucer.lee@foxmail.com>
> Date: Mon, 3 Feb 2020 23:38:11 +0800
> Subject: [PATCH v3] erofs-utils: introduce exclude dirs and files
> 
> Add excluded file feature "--exclude-path=", which can be used
> to build EROFS image without some user specific files or dirs.
> 
> Note that you may give multiple `--exclude-path' options.
> 
> Signed-off-by: Li Guifu <blucer.lee@foxmail.com>
> Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
> ---
> changes since v2:
>  - cleanup the whole implementation;
>  - complete usage message;
>  - complete manual page.
> 
>  include/erofs/exclude.h | 23 +++++++++++
>  lib/Makefile.am         |  2 +-
>  lib/exclude.c           | 89 +++++++++++++++++++++++++++++++++++++++++
>  lib/inode.c             |  5 +++
>  man/mkfs.erofs.1        |  4 ++
>  mkfs/main.c             | 26 +++++++++---
>  6 files changed, 142 insertions(+), 7 deletions(-)
>  create mode 100644 include/erofs/exclude.h
>  create mode 100644 lib/exclude.c
> 
> diff --git a/include/erofs/exclude.h b/include/erofs/exclude.h
> new file mode 100644
> index 0000000..580fefe
> --- /dev/null
> +++ b/include/erofs/exclude.h
> @@ -0,0 +1,23 @@
> +/* SPDX-License-Identifier: GPL-2.0+ */
> +/*
> + * erofs-utils/include/erofs/exclude.h
> + *
> + * Created by Li Guifu <blucer.lee@foxmail.com>
> + */
> +#ifndef __EROFS_EXCLUDE_H
> +#define __EROFS_EXCLUDE_H
> +
> +struct erofs_exclude_rule {
> +	struct list_head list;
> +
> +	char *pattern;
> +};
> +
> +void erofs_exclude_set_root(const char *rootdir);
> +void erofs_cleanup_exclude_rules(void);
> +
> +int erofs_parse_exclude_path(const char *args);
> +struct erofs_exclude_rule *erofs_is_exclude_path(const char *dir,
> +						 const char *name);
> +#endif
> +
> diff --git a/lib/Makefile.am b/lib/Makefile.am
> index 1ff81f9..e4b51e6 100644
> --- a/lib/Makefile.am
> +++ b/lib/Makefile.am
> @@ -3,7 +3,7 @@
>  
>  noinst_LTLIBRARIES = liberofs.la
>  liberofs_la_SOURCES = config.c io.c cache.c inode.c xattr.c \
> -		      compress.c compressor.c
> +		      compress.c compressor.c exclude.c
>  liberofs_la_CFLAGS = -Wall -Werror -I$(top_srcdir)/include
>  if ENABLE_LZ4
>  liberofs_la_CFLAGS += ${LZ4_CFLAGS}
> diff --git a/lib/exclude.c b/lib/exclude.c
> new file mode 100644
> index 0000000..9b48325
> --- /dev/null
> +++ b/lib/exclude.c
> @@ -0,0 +1,89 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * erofs-utils/lib/exclude.c
> + *
> + * Created by Li Guifu <blucer.lee@foxmail.com>
> + */
> +#include <string.h>
> +#include <stdlib.h>
> +#include "erofs/err.h"
> +#include "erofs/list.h"
> +#include "erofs/print.h"
> +#include "erofs/exclude.h"
> +
> +static LIST_HEAD(exclude_head);
> +static unsigned int rpathlen;		/* root directory prefix length */
> +
> +void erofs_exclude_set_root(const char *rootdir)
> +{
> +	rpathlen = strlen(rootdir);
> +}
> +
> +static struct erofs_exclude_rule *erofs_insert_exclude(const char *s)
> +{
> +	struct erofs_exclude_rule *e;
> +
> +	e = malloc(sizeof(*e));
> +	if (!e)
> +		return ERR_PTR(-ENOMEM);
> +
> +	/* exact match */
> +	e->pattern = strdup(s);
> +	if (!e->pattern) {
> +		free(e);
> +		return ERR_PTR(-ENOMEM);
> +	}
> +
> +	list_add_tail(&e->list, &exclude_head);
> +	erofs_info("exclude path %s inserted", e->pattern);
> +	return e;
> +}
> +
> +void erofs_cleanup_exclude_rules(void)
> +{
> +	struct erofs_exclude_rule *e, *n;
> +
> +	list_for_each_entry_safe(e, n, &exclude_head, list) {
> +		list_del(&e->list);
> +		free(e->pattern);
> +		free(e);
> +	}
> +}
> +
> +int erofs_parse_exclude_path(const char *args)
> +{
> +	struct erofs_exclude_rule *e = erofs_insert_exclude(args);
> +
> +	if (IS_ERR(e)) {
> +		erofs_cleanup_exclude_rules();
> +		return PTR_ERR(e);
> +	}
> +	return 0;
> +}
> +
> +struct erofs_exclude_rule *erofs_is_exclude_path(const char *dir,
> +						 const char *name)
> +{
> +	char buf[PATH_MAX];
> +	const char *s;
> +	struct erofs_exclude_rule *e;
> +
> +	if (!dir) {
> +		/* no prefix */
> +		s = name;
> +	} else {
> +		sprintf(buf, "%s/%s", dir, name);
> +		s = buf;
> +	}
> +
> +	s += rpathlen;
> +	while (*s == '/')
> +		s++;
> +
> +	list_for_each_entry(e, &exclude_head, list) {
> +		if (!strcmp(e->pattern, s))
> +			return e;
> +	}
> +	return NULL;
> +}
> +
> diff --git a/lib/inode.c b/lib/inode.c
> index bd0652b..7114023 100644
> --- a/lib/inode.c
> +++ b/lib/inode.c
> @@ -20,6 +20,7 @@
>  #include "erofs/io.h"
>  #include "erofs/compress.h"
>  #include "erofs/xattr.h"
> +#include "erofs/exclude.h"
>  
>  struct erofs_sb_info sbi;
>  
> @@ -877,6 +878,10 @@ struct erofs_inode *erofs_mkfs_build_tree(struct erofs_inode *dir)
>  		    !strncmp(dp->d_name, "lost+found", strlen("lost+found")))
>  			continue;
>  
> +		/* skip if it's a exclude file */
> +		if (erofs_is_exclude_path(dir->i_srcpath, dp->d_name))
> +			continue;
> +
>  		d = erofs_d_alloc(dir, dp->d_name);
>  		if (IS_ERR(d)) {
>  			ret = PTR_ERR(d);
> diff --git a/man/mkfs.erofs.1 b/man/mkfs.erofs.1
> index d6bf828..aa927a9 100644
> --- a/man/mkfs.erofs.1
> +++ b/man/mkfs.erofs.1
> @@ -52,6 +52,10 @@ Forcely generate extended inodes (64-byte inodes) to output.
>  Set all files to the given UNIX timestamp. Reproducible builds requires setting
>  all to a specific one.
>  .TP
> +.BI "\-\-exclude-path=" path
> +Ignore file that matches the exact literal path.
> +You may give multiple `--exclude-path' options.
> +.TP
>  .B \-\-help
>  Display this help and exit.
>  .SH AUTHOR
> diff --git a/mkfs/main.c b/mkfs/main.c
> index 817a6c1..d913b5d 100644
> --- a/mkfs/main.c
> +++ b/mkfs/main.c
> @@ -21,6 +21,7 @@
>  #include "erofs/io.h"
>  #include "erofs/compress.h"
>  #include "erofs/xattr.h"
> +#include "erofs/exclude.h"
>  
>  #ifdef HAVE_LIBUUID
>  #include <uuid/uuid.h>
> @@ -30,6 +31,7 @@
>  
>  static struct option long_options[] = {
>  	{"help", no_argument, 0, 1},
> +	{"exclude-path", required_argument, NULL, 2},
>  	{0, 0, 0, 0},
>  };
>  
> @@ -50,12 +52,13 @@ static void usage(void)
>  {
>  	fputs("usage: [options] FILE DIRECTORY\n\n"
>  	      "Generate erofs image from DIRECTORY to FILE, and [options] are:\n"
> -	      " -zX[,Y]   X=compressor (Y=compression level, optional)\n"
> -	      " -d#       set output message level to # (maximum 9)\n"
> -	      " -x#       set xattr tolerance to # (< 0, disable xattrs; default 2)\n"
> -	      " -EX[,...] X=extended options\n"
> -	      " -T#       set a fixed UNIX timestamp # to all files\n"
> -	      " --help    display this help and exit\n"
> +	      " -zX[,Y]          X=compressor (Y=compression level, optional)\n"
> +	      " -d#              set output message level to # (maximum 9)\n"
> +	      " -x#              set xattr tolerance to # (< 0, disable xattrs; default 2)\n"
> +	      " -EX[,...]        X=extended options\n"
> +	      " -T#              set a fixed UNIX timestamp # to all files\n"
> +	      " --exclude-path=X avoid including file X (X = exact literal path)\n"
> +	      " --help           display this help and exit\n"
>  	      "\nAvailable compressors are: ", stderr);
>  	print_available_compressors(stderr, ", ");
>  }
> @@ -178,6 +181,15 @@ static int mkfs_parse_options_cfg(int argc, char *argv[])
>  			}
>  			break;
>  
> +		case 2:
> +			opt = erofs_parse_exclude_path(optarg);
> +			if (opt) {
> +				erofs_err("failed to parse exclude path: %s",
> +					  erofs_strerror(opt));
> +				return opt;
> +			}
> +			break;
> +
>  		case 1:
>  			usage();
>  			exit(0);
> @@ -372,6 +384,7 @@ int main(int argc, char **argv)
>  	}
>  
>  	erofs_show_config();
> +	erofs_exclude_set_root(cfg.c_src_path);
>  
>  	sb_bh = erofs_buffer_init();
>  	if (IS_ERR(sb_bh)) {
> @@ -428,6 +441,7 @@ int main(int argc, char **argv)
>  exit:
>  	z_erofs_compress_exit();
>  	dev_close();
> +	erofs_cleanup_exclude_rules();
>  	erofs_exit_configure();
>  
>  	if (err) {
>