Пример #1
0
Файл: util.c Проект: asias/vm
/**
 * strlcat - Append a length-limited, %NUL-terminated string to another
 * @dest: The string to be appended to
 * @src: The string to append to it
 * @count: The size of the destination buffer.
 */
size_t strlcat(char *dest, const char *src, size_t count)
{
	size_t dsize = strlen(dest);
	size_t len = strlen(src);
	size_t res = dsize + len;

	DIE_IF(dsize >= count);

	dest += dsize;
	count -= dsize;
	if (len >= count)
		len = count - 1;

	memcpy(dest, src, len);
	dest[len] = 0;

	return res;
}
/* Parse probepoint definition. */
static void parse_perf_probe_probepoint(char *arg, struct probe_point *pp)
{
	char *ptr, *tmp;
	char c, nc = 0;
	/*
	 * <Syntax>
	 * perf probe [EVENT=]SRC[:LN|;PTN]
	 * perf probe [EVENT=]FUNC[@SRC][+OFFS|%return|:LN|;PAT]
	 *
	 * TODO:Group name support
	 */

	ptr = strpbrk(arg, ";=@+%");
	if (ptr && *ptr == '=') {	/* Event name */
		*ptr = '\0';
		tmp = ptr + 1;
		ptr = strchr(arg, ':');
		if (ptr)	/* Group name is not supported yet. */
			semantic_error("Group name is not supported yet.");
		if (!check_event_name(arg))
			semantic_error("%s is bad for event name -it must "
				       "follow C symbol-naming rule.", arg);
		pp->event = strdup(arg);
		arg = tmp;
	}

	ptr = strpbrk(arg, ";:+@%");
	if (ptr) {
		nc = *ptr;
		*ptr++ = '\0';
	}

	/* Check arg is function or file and copy it */
	if (strchr(arg, '.'))	/* File */
		pp->file = strdup(arg);
	else			/* Function */
		pp->function = strdup(arg);
	DIE_IF(pp->file == NULL && pp->function == NULL);

	/* Parse other options */
	while (ptr) {
		arg = ptr;
		c = nc;
		if (c == ';') {	/* Lazy pattern must be the last part */
			pp->lazy_line = strdup(arg);
			break;
		}
		ptr = strpbrk(arg, ";:+@%");
		if (ptr) {
			nc = *ptr;
			*ptr++ = '\0';
		}
		switch (c) {
		case ':':	/* Line number */
			pp->line = strtoul(arg, &tmp, 0);
			if (*tmp != '\0')
				semantic_error("There is non-digit char"
					       " in line number.");
			break;
		case '+':	/* Byte offset from a symbol */
			pp->offset = strtoul(arg, &tmp, 0);
			if (*tmp != '\0')
				semantic_error("There is non-digit character"
						" in offset.");
			break;
		case '@':	/* File name */
			if (pp->file)
				semantic_error("SRC@SRC is not allowed.");
			pp->file = strdup(arg);
			DIE_IF(pp->file == NULL);
			break;
		case '%':	/* Probe places */
			if (strcmp(arg, "return") == 0) {
				pp->retprobe = 1;
			} else	/* Others not supported yet */
				semantic_error("%%%s is not supported.", arg);
			break;
		default:
			DIE_IF("Program has a bug.");
			break;
		}
	}

	/* Exclusion check */
	if (pp->lazy_line && pp->line)
		semantic_error("Lazy pattern can't be used with line number.");

	if (pp->lazy_line && pp->offset)
		semantic_error("Lazy pattern can't be used with offset.");

	if (pp->line && pp->offset)
		semantic_error("Offset can't be used with line number.");

	if (!pp->line && !pp->lazy_line && pp->file && !pp->function)
		semantic_error("File always requires line number or "
			       "lazy pattern.");

	if (pp->offset && !pp->function)
		semantic_error("Offset requires an entry function.");

	if (pp->retprobe && !pp->function)
		semantic_error("Return probe requires an entry function.");

	if ((pp->offset || pp->line || pp->lazy_line) && pp->retprobe)
		semantic_error("Offset/Line/Lazy pattern can't be used with "
			       "return probe.");

	pr_debug("symbol:%s file:%s line:%d offset:%d return:%d lazy:%s\n",
		 pp->function, pp->file, pp->line, pp->offset, pp->retprobe,
		 pp->lazy_line);
}