Commit 21dd9ae5 authored by Franck Bui-Huu's avatar Franck Bui-Huu Committed by Arnaldo Carvalho de Melo
Browse files

perf probe: Handle gracefully some stupid and buggy line syntaxes 



Currently perf probe doesn't handle those incorrect syntaxes:

   $ perf probe -L sched.c:++13
   $ perf probe -L sched.c:-+13
   $ perf probe -L sched.c:10000000000000000000000000000+13

This patches rewrites parse_line_range_desc() to handle them.

As a bonus, it reports more useful error messages instead of: "Tailing
with invalid character...".

Acked-by: default avatarMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
LKML-Reference: <1292854685-8230-7-git-send-email-fbuihuu@gmail.com>
Signed-off-by: default avatarFranck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent fde52dbd

tools/perf/util/probe-event.c

+60 −32
Original line number Diff line number Diff line
@@ -529,6 +529,19 @@ int show_available_vars(struct perf_probe_event *pevs __unused, 
}

#endif



static int parse_line_num(char **ptr, int *val, const char *what)

{

	const char *start = *ptr;



	errno = 0;

	*val = strtol(*ptr, ptr, 0);

	if (errno || *ptr == start) {

		semantic_error("'%s' is not a valid number.\n", what);

		return -EINVAL;

	}

	return 0;

}



/*

 * Stuff 'lr' according to the line range described by 'arg'.

 * The line range syntax is described by:
@@ -538,50 +551,65 @@ int show_available_vars(struct perf_probe_event *pevs __unused, 
 */

int parse_line_range_desc(const char *arg, struct line_range *lr)

{

	const char *ptr;

	char *tmp;

	char *range, *name = strdup(arg);

	int err;



	ptr = strchr(arg, ':');

	if (ptr) {

		lr->start = (int)strtoul(ptr + 1, &tmp, 0);

		if (*tmp == '+') {

			lr->end = lr->start + (int)strtoul(tmp + 1, &tmp, 0);

			lr->end--;	/*

	if (!name)

		return -ENOMEM;



	lr->start = 0;

	lr->end = INT_MAX;



	range = strchr(name, ':');

	if (range) {

		*range++ = '\0';



		err = parse_line_num(&range, &lr->start, "start line");

		if (err)

			goto err;



		if (*range == '+' || *range == '-') {

			const char c = *range++;



			err = parse_line_num(&range, &lr->end, "end line");

			if (err)

				goto err;



			if (c == '+') {

				lr->end += lr->start;

				/*

				 * Adjust the number of lines here.

				 * If the number of lines == 1, the

				 * the end of line should be equal to

				 * the start of line.

				 */

		} else if (*tmp == '-')

			lr->end = (int)strtoul(tmp + 1, &tmp, 0);

		else

			lr->end = INT_MAX;

				lr->end--;

			}

		}



		pr_debug("Line range is %d to %d\n", lr->start, lr->end);



		err = -EINVAL;

		if (lr->start > lr->end) {

			semantic_error("Start line must be smaller"

				       " than end line.\n");

			return -EINVAL;

			goto err;

		}

		if (*tmp != '\0') {

			semantic_error("Tailing with invalid character '%d'.\n",

				       *tmp);

			return -EINVAL;

		if (*range != '\0') {

			semantic_error("Tailing with invalid str '%s'.\n", range);

			goto err;

		}

		tmp = strndup(arg, (ptr - arg));

	} else {

		tmp = strdup(arg);

		lr->end = INT_MAX;

	}



	if (tmp == NULL)

		return -ENOMEM;



	if (strchr(tmp, '.'))

		lr->file = tmp;

	if (strchr(name, '.'))

		lr->file = name;

	else

		lr->function = tmp;

		lr->function = name;



	return 0;

err:

	free(name);

	return err;

}



/* Check the name is good for event/group */

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