show: Rework show procedure

Added

 - ability to parse every single file crtools
   understands via magic number

 - dumped memory pages can be rendered in two
   modes -- as a simple set of pages' virtual addresses
   or in hexdummp fashion (via -c command line key).

For example

  ./crtools -s -c -f pages-2557.img

CR_FD_PAGES: pages-2557.img
----------------------------------------
    7fffb44ace20: 00 00 00 00 00 00 00 00  00 00 00 74 65 73 74 2f  |. . . . . . . .  . . . t e s t / |
    7fffb44ace30: 74 65 73 74 2d 73 69 67  61 63 74 69 6f 6e 00 48  |t e s t - s i g  a c t i o n . H |
    7fffb44ace40: 4f 53 54 4e 41 4d 45 3d  6c 6f 63 61 6c 68 6f 73  |O S T N A M E =  l o c a l h o s |
    7fffb44ace50: 74 2e 6c 6f 63 61 6c 64  6f 6d 61 69 6e 00 54 45  |t . l o c a l d  o m a i n . T E |
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

cr-dump.c

@@ -45,7 +45,7 @@
 static char big_buffer[PATH_MAX];
 static char loc_buf[PAGE_SIZE];
 
-static void free_pstree(struct list_head *pstree_list)
+void free_pstree(struct list_head *pstree_list)
 {
 	struct pstree_item *item, *p;
 

crtools.c

@@ -233,7 +233,7 @@ int main(int argc, char *argv[])
 	int opt, idx;
 	int action = -1;
 
-	static const char short_opts[] = "drskp:t:h";
+	static const char short_opts[] = "drskf:p:t:hc";
 	static const struct option long_opts[] = {
 		{ "dump",	no_argument, NULL, 'd' },
 		{ "restore",	no_argument, NULL, 'r' },
@@ -274,6 +274,13 @@ int main(int argc, char *argv[])
 		case 's':
 			action = opt;
 			break;
+		case 'c':
+			opts.show_pages_content	= true;
+			break;
+		case 'f':
+			opts.show_single_file = true;
+			opts.show_dump_file = optarg;
+			break;
 		case 'k':
 			opts.final_state = CR_TASK_KILL;
 			break;
@@ -302,6 +309,10 @@ int main(int argc, char *argv[])
 
 usage:
 	printk("\nUsage:\n");
-	printk("\tcrtools ([--dump|-d]|[--show|-s]|[--restore|-r]) [-k] (-p|-t) pid\n\n");
+	printk("\t%s --dump|-d [-k] -p|-t pid\n", argv[0]);
+	printk("\t%s --restore|-r -p|-t pid\n", argv[0]);
+	printk("\t%s --show|-s [-c] (-p|-t pid)|(-f file)\n", argv[0]);
+	printk("\n");
+
 	return -1;
 }

include/crtools.h

@@ -9,6 +9,7 @@
 #include "image.h"
 
 extern struct page_entry zero_page_entry;
+extern void free_pstree(struct list_head *pstree_list);
 
 #define CR_FD_PERM		(S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH)
 #define CR_FD_PERM_DUMP		(S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH)
@@ -35,6 +36,9 @@ enum cr_task_final_state {
 struct cr_options {
 	bool				leader_only;
 	enum cr_task_final_state	final_state;
+	bool				show_single_file;
+	bool				show_pages_content;
+	char				*show_dump_file;
 };
 
 /* file descriptors template */