lkml.org 
[lkml]   [2011]   [Oct]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 09/26] dynamic_debug: process multiple commands on a line
Date
From: Jim Cromie <jim.cromie@gmail.com>

Process multiple commands per line, separated by ';' or '\n'.
All commands are processed, independent of errors, allowing individual
commands to fail, for example when a module is not installed. Errors
are counted, and last error code is returned.

With this, extensive command sets can be given on the boot-line.

Splitting on '\n' allows "cat cmd-file > /dbg/dynamic_debug/control"
where cmd-file contains multiple queries, one per line. Empty commands
are skipped, allowing ";\n\n" to not count as errors.

Splitting on '\n' prevents its use in a format-spec, but thats not very
useful anyway, searching for meaningful and selective substrings is typical.

Also allow comment lines, starting with '#', with optional leading whitespace.
Trailing comments are allowed, if preceded by ';' which terminates
the command on the line. For example:

root@voyage:~# cat debugfs-file

# blank lines ok, comments too
module foo +p
# multiple cmds on line, with ; to separate them
module bar +p ; module buz +p ; # trailing comments need cmd terminator too

root@voyage:~# cat debugfs-file > /dbg/dynamic_debug/control

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
---
lib/dynamic_debug.c | 35 +++++++++++++++++++++++++++++++++--
1 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index b88f918..4bf27f3 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -444,6 +444,35 @@ static int ddebug_exec_query(char *query_string)
return 0;
}

+/* handle multiple queries, continue on error, return last error */
+static int ddebug_exec_queries(char *query)
+{
+ char *split;
+ int i, errs = 0, exitcode = 0, rc;
+
+ for (i = 0; query; query = split) {
+ split = strpbrk(query, ";\n");
+ if (split)
+ *split++ = '\0';
+
+ query = skip_spaces(query);
+ if (!*query || *query == '#')
+ continue;
+ if (verbose)
+ pr_info("query %d: \"%s\"\n", i, query);
+
+ rc = ddebug_exec_query(query);
+ if (rc) {
+ errs++;
+ exitcode = rc;
+ }
+ i++;
+ }
+ pr_info("processed %d queries, with %d errs\n", i, errs);
+
+ return exitcode;
+}
+
#define PREFIX_SIZE 64
#define LEFT(wrote) ((PREFIX_SIZE - wrote) > 0) ? (PREFIX_SIZE - wrote) : 0

@@ -578,7 +607,7 @@ static ssize_t ddebug_proc_write(struct file *file, const char __user *ubuf,
if (verbose)
pr_info("read %d bytes from userspace\n", (int)len);

- ret = ddebug_exec_query(tmpbuf);
+ ret = ddebug_exec_queries(tmpbuf);
if (ret)
return ret;

@@ -883,7 +912,9 @@ static int __init dynamic_debug_init(void)

/* ddebug_query boot param got passed -> set it up */
if (ddebug_setup_string[0] != '\0') {
- ret = ddebug_exec_query(ddebug_setup_string);
+ pr_info("ddebug initializing with string \"%s\"",
+ ddebug_setup_string);
+ ret = ddebug_exec_queries(ddebug_setup_string);
if (ret)
pr_warn("Invalid ddebug boot param %s",
ddebug_setup_string);
--
1.7.4.4


\
 
 \ /
  Last update: 2011-10-07 22:37    [W:0.296 / U:10.900 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site